This paper discusses a method for representing symbols in a ps.d.o. using two bases and a lifting functional, grounded in an invariance principle and boundary conditions.
Contribution
It introduces a novel approach to symbol representation in ps.d.o. leveraging dual bases and boundary conditions based on invariance principles.
Findings
01
Successful representation of symbols using the proposed method
02
The approach is grounded in invariance principles and boundary conditions
03
Potential applications in symbolic analysis and processing
Abstract
I will attempt to represent a symbol to a ps.d.o., using two bases and a lifting functional. The representation is based upon an invariance principle and conditions on the boundary, defined by first surfaces to the symbol.
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Taxonomy
TopicsSpectral Theory in Mathematical Physics · advanced mathematical theories · Algebraic and Geometric Analysis
Full text
SOME REMARKS ON MIXED PROBLEMS
Tove Dahn
1 Introduction
The model we start with can be compared with a lifting principle, F(γ)(ζ)=f(ζ), ζ∈Rn
where g(ζ)=f(ζ) and E=F. When γ polynomial in an ideal (I),
we assume thus that we have existence of F analytic, such that E∗γ(D)δ=g.
More generally we can assume existence of E∈DL1′,such that E(γ)=g.
We will restrict our attention to symbols f with log∣f∣∈L1 and for a very regular boundary
([3]), we argue that the model can be represented using polynomial γ.
By further using the moment problem, we can continue F to C,
given that the measure to (I)⊥ is of bounded variation. If further for instance the measure is reduced,
we can continue to E′.
We consider it as necessary for a global model to have a representation of the complementary ideal.
Assume the analytic symbols have a decomposition (I)⊕(I)⊥, we use the moment problem
to generalize this orthogonality ([4]).
Assume that we have a continuous mapping (I)∋γ1→γ2∈(I⊥).
A global model is invariant for change of local coordinates. We discuss instead a model invariant
for change of pairs of coordinates H(γ)=H1H2(γ). Note that if H polynomial,
we do not necessarily have H1,H2 polynomials. We discuss F(γ1→γ2)(ζ),
where γ1 is hyperbolic and γ2 partially hypoelliptic.
We assume an invariance principle for movements in (I), so that any movement of (I) has an exact
correspondent movement in (I)⊥ and conversely. When the movement V has an analytic representation, we have a continuous mapping V→V~ into
the domain for ζ. The main result that we will discuss in this paper is:
Main result**.**
Assume γ1∈(I1) an analytic symbol and consider a continuation (I1)∋γ1→γδ∈(I1)⊥,
for a parameter δ. We assume there is a set Δ (lineality), where γ1=γδ.
We then have, given f(ζ) analytic, a solution Fδ, such that Fδ(γδ)(ζ)=f(ζ).
We assume the continuation such that
dx1dFδ/dy1dFδ=dxδdFδ/dyδdFδ, under
the following conditions on the boundary: The boundary is given by the first surfaces S to f(ζ),
that can be reached in at least one of three ways.
1
S* can be reached by Δ*
2
S* can be reached through a movement V⊥←U⊥, such that
V⊥~ and V~ do not have points in common outside S.*
3
S* can be reached through an algebraic trajectory.*
Note that the mixed problem usually is given as Fγδ=fδ. But if we assume γ1
has a fundamental solution E1 and tE1tγδF=FγδE1,
then tE1tγδFγ1=fδ, where fδ=tE1tγδf
2 The invariance principle
We start with ([21]) a movement on the hyperboloid L(Ux,Uy)=L(x,y), that is tU∼U−1
with respect to a lorentz metric form L.
The reflection invariance is defined by L(Ux,y)=L(x,y) implies y=0, in this case U∼I.
Particularly, we define the light cone L(x,y)=0, that is x⊥y with respect to L.
Parallel to this we discuss a en movement with respect to euclidean metric E(Vx,Vy)=E(x,y) that is tV∼V−1
with respect to E and we have an axes for invariance E(Vx,y)=E(x,y) implies y=0 and we conclude V∼I.
When the movements are reflections, they are involutive.
The idea behind the model
is that an hyperbolic movement exactly corresponds to an euclidean translation. In the non- euclidean plane
we do not have any proper translation, but given two points p,q there is a unique hyperbolic rotation
that maps p onto q and for which “the line” through the points is a trajectory. In this manner
the rotation axes is
conjugated to the plane through the origo and the points p,q. ([21]).
Consider now γ1∈(I1) where orthogonality is relative L and simultaneously γ2∈(I1)⊥
with orthogonality relative E. Using Radon Nikodym’s theorem, we will continuously continue γ1→γ2.
Assume <γ1,γ2>=0 and Uγ1→Iγ1 through a closed sequence
(continuous), say M. We can argue that M=∘(M∘), that is if the condition
<(U−I)γ1,(V−I)γ2>=0 implies V→I and conversely, when V=I, we have that U=I and we have a geometric invariance principle.
Assume J:γ1→γ2 continuous and VJ=JU, then
using the relation above for M we have motivated an invariance principle.
We are here assuming
<Uγ1,Vγ2>=0 and <(U−I)γ1,γ2>=<γ1,(V−I)γ2>=0 on Δ.
Now for the particular movements, we have
τJ=Jh, eJ=Je~ where τ is translation, h a hyperbolic movement and e,e~
rotation. Characteristic for
parabolic movements is a constant (euclidean) distance to the light cone (rotation axes).
Characteristic for elliptic and hyperbolic movements is that the rotation axes R are one sided, that is
∣x∣<∣y∣ or ∣x∣>∣y∣. Thus if we consider η(x)=y/x we have
that the axes R1→∣η∣<1 (hyperbolic) and R2→∣η∣>1 (elliptic)
and R3→∣η∣=1 (parabolic). We can as usual map ∣η∣<1
on a half plane, in this way we can consider movement as “one sided”. In particular the hyperbolic and elliptic movements map
half planes on to half planes.
Elliptic rotation can be represented through ei<a⋅x,a∗⋅x∗>, where a is a
scalar vector and where a∗, is defined such that <a⋅x,a∗x∗>=<x,x∗>,
that is elliptic rotation is immediately represented in euclidean geometry. Using the Fourier Borel
transform, we can further associate elliptic rotation to translation of the symbol.
Assume the invariance principle JU=VJ and x→x∗ according to Legendre (reciprocal polars)
and note that <x,x∗>=<x∗,x> implies a normal transform.
We look for a continuous mapping V⊥→V∗. Assume Ve corresponds to
rotational movement and let Ve~ denote the inverse mapping, that is Vef→Ve~ζ,
we then have Ve⊥∋x→x∗∈Vh using Legendre,
that is (Vh)∗→(Ve⊥) (reflexivity). In the same manner
(Ve)∗≃(Vh)⊥ and (Vp)∗≃(Vp⊥)≃(Vp).
Formally (ei<x,⋅>+v(x)f)∨=τf(x∗). Using Parseval we have equivalent
sets in L2. If we define a regular approximation through H(Uφ)≡0, if we assume
dxdH=0 and H analytic, we have continuous induced relations for the inverse movements V~
For simplicity we will in this article consider
one movement at a time, when we apply Radon-Nikodym’s theorem and since the movements are not
dependent on sign of L, is sufficient to consider positive linear functionals.
Assume Δ a domain for the movement I and γ1=γ2 on Δ. Assume (U−I)γ1=0 with respect to L
and (V−I)γ2=0 with respect to E and F(JUγ1)=F(evVγ2) with v∈L1
where v=0 on Δ. Note that the last condition is dependent on the movement.
Assume w(η)=w(xy)=v(x,y)
and assume xdxdη=−dxdy−yx. Further let du=x1dx−y1dy
then we have that −dη=du∗, the harmonic conjugate.
As w=0, over Δ we have for a trajectory to η, that analyticity is preserved under the condition on vanishing flux ∫Sdu∗=0
(a transmission property).
Note ([2])
that for X=dx/dt,Y=dy/dt, (xX+yY)/(xY−yX) is passing through [math] precisely like −x/y−Y/X. We assume in
the discussion that
Y/X is not affected by the movement (Lie’s point transform). Note also, that if
Y/X=ρ>1, we have if U→I, that ρ>1 (hyperbolic) for degenerate points,
why if we limit ourselves to elliptic approximations, we do not have degenerate points.
The invariance principle for movements, has a correspondent principle in operator space.
Note that if we start from the parametrices as
Fredholm operators, with a decomposition N(E)⨁D(E), we see that modulo C∞,
that parametrices to hypoelliptic operators have N(E)={0}. Orthogonality for the symbol space
induces a corresponding relation in the operator space. If for two analytic symbols f1,f2, we assume
f1≺f2, we note that a necessary condition for inclusion for the correspondent space of
operators is f1≺≺f2. Thus, we have existence of N, such that for the operator space
dxdf1N≺f2N. In particular, we can write dxdlogf1N→0
for some N and simultaneously f1N≺f2N. Note that for a polynomial, we have
always dxdP≺P. Further, if \mboxradf2⊂\mboxradf1,
we have N1⊂N2, for the corresponding zero space. Radon Nikodym’s theorem can be used,
I(f1)=I(gf2), for g∈L1. The conclusion is that a necessary condition for inclusion
of the corresponding operator spaces, is that one symbol ideal is strictly weaker that the other and
a strict dominance of symbol ideals implies an inclusion of operator spaces.
It is for this sufficient to consider the phase space, logf1N≺logf2N
and dxdlogf1→0 in the ∞ implies (I2)⊂(I1).
Note that ([23]) D is dense in DLp and in
B˙, but not in B. We have that (B˙)′=DL1′ and (B)′=DL∞′.
Further we have that (B˙)′ is the limit in B′ of E′.
Concerning f∈(I1)⊂(IHe)⊥, we assume (IHe) with a global pseudo base
and <f,dμ>=0 continued to <f~,dμ>=0. Assume the
continuation f~∼egf with g∈L1, that is f⊥e−gdμ. If dv
corresponds to (IPhe), such that dv∼e−gdμ, then egdv is downward bounded.
Another example is given by dμ of type [math],
e−g1dμ of type A1, further e−gdμ of finite type. A final example
is given by dμ with a trivial kernel.
Assume γ1=γ2, on Δ and construct a neighbourhood JUγ1=VJγ1=Vγ2.
We have Uγ12=(Uγ1)2, but Vγ22=(Vγ2)2 and
V(evγ2)∼JUγ1 and Jγ1(2)=ev2γ2(2),
we then have v2=v1, but v1=v2 on Δ. For instance:
{0}=Δ(γ2(2))⊂Δ(γ2)=Δ(γ1)=Δ(γ1(2)).
Thus, {ev2−1}⊂{ev1−1}, that is {v2=0}⊂{v1=0}
and for the correspondent geometric ideal, we have I1⊂I2. When we assume U linear
in γ, we do not assume U simultaneously linear in ζ, for V we do not assume V linear in
ϕ or ζ. V=JUJ−1 and I=IHyp implies VI⊥=JUI.
The boundary is defined by first surfaces S, invariant for all movements
and S0=S\{x0}.
Existence of regular approximations is guaranteed
by Δ. Transversals are associated to reflection axles in S, we consider one movement at a time.
Δ is represented by U⊥=I and the choice of movement determines the properties of the neighbourhood of Δ.
When γ preserves a constant value in the ∞, we have γ(x,y)∼P(x1,y1),
as x,y→∞, for a polynomial P and we can determine ⊥ as independent of ∣x∣,∣y∣→∞.
In the case when the regular approximation does not have a reduced ⊥ measure, that is
∫gregdμ=0 where dμ is not reduced, we must take into account orbits among the
possible approximations.
Sufficient for this to occur, is that we do an adjustment with point support measure
in Cousin’s continuation over the boundary ([3], cfr the last section in this article). Thus, for a reduced representation in
the moment problem for the measure, we can assume transversals without orbits or orientation of orbits.
Assume f=eϕ, and consider the problem when U preserves analyticity. If \big{[}U,I\big{]}=\big{[}I,U\big{]}
and U is acting linearly in the phase, we have that U(f1f2)=eUϕ1+Uϕ2=U(f1)U(f2) (“point topology”). Note that if U=I on W planar in OAD ([1]),
we have that U linear.
When U=I on W∋∞ planar, we must assume (X,Y)T→(X,Y)1/T continuous.
When U→V, it is not sufficient to consider tangents and we assume FT→F1/T
preserves continuity over the axes for invariance.
Note that when U is linear over ϕ, we can assume U(ϕ)=U(ϕ),
U(iϕ)=iU(ϕ) and U(−ϕ)=−U(ϕ). In particular this can be assumed when ϕ defines a planar domain
ϕ1⊥ϕ2 in OAD (or standard complexified). For Jϕ, we have
for some iterate ϕ1N⊥ϕ2N, however we also have a ev for v∈L1
according to Radon-Nikodym’s theorem, that is we have a non planar domain.
Since v is determined by the movement, we will argue that it is sufficient to consider a domain for v
on one side of a hyperplane.
Invariance principle**.**
By considering movements as functionals, we can uniquely relate movements on the hyperboloid to movements
in an euclidean metric. We assume J:γ1→γ2 continuous and γ1=γ2
on a set Δ={0}. If we assume γj analytic and γ2 reduced
with respect to γ1, we can represent F(Jγ1)=F(evγ2) and v∈L1
The boundary measure represents a very regular distribution B in DL1′, with kernel
B⊂L1.
That is we do not assume γj∈L1, but dγ1dγ2∈L1 with
respect to the boundary measure. Thus, since γ2 is reduced, dγ1dv is in L1
and we can conclude that v∈L1 with respect to the boundary measure. The boundary distribution is
thus of real type ([15]) and it is sufficient to consider Rn for the definition of boundary
condition. If we assume B(ev)=B(v)∈L1
implies v∈L1, we have that v∈L1(Rn).
Concerning the boundary condition, we note that the condition on a very regular boundary δ0−C∞
does not imply analyticity. The proposition that \mboxkerE (parametrix) can be replaced by
C∞, is implied by homogeneous hypoellipticity.
3 Movements
Assume that π is a plane through the origo and K is the light cone. We define
VR:π∩K={0},VL:π∩K={L},VT:π∩K={L1,L2}.
Assume R reflection points (invariant points). We then have R∈VT implies elliptic
movements, R∈VL implies parabolic movements, R∈VR implies hyperbolic movements.
Every movement on the hyperboloid, can be given as reflections with respect to a plane through a fixed point.
They are divided into direct movements: reflection with respect to a plane through an axes and indirect
movements: reflection with respect to a plane through a point. We can for instance assume the axes
x=y and the point is 0.
The lineality Δ is defined in the domain Ω through translation invariance for an analytic symbol.
The corresponding movement in lorentz geometry is I, that is
Iγ=γ. More precisely τF(γ)(ζ)=F(γ)(ζ)
or equivalently F(Uγ)=F(γ)=F(Iγ). Assume U→I is a movement and
let U→U~ be the mapping (I)→Ω. Given Uγ
analytical, we have that U~ζ defines a neighbourhood of Δ.
In the same manner, if we let U⊥→I,
with U⊥→U~⊥, this does not imply U⊥γ∈Hm, but given
U⊥γ analytic, we have that U~⊥ζ is continuous. Note that without the condition
on analyticity, we do not have limU→IU~=limU⊥→IU~⊥
For this reason, we define Δ={ζIγ=γγ∈(I)}, where
(I)={γF(γ)(ζ)=f(ζ)} for some F. Ω can be defined through
{ζUγ(ζ)\mboxclosetoγ(ζ)ζ∈Δ}.
In the same manner, we can define Δ⊥={ζIγ=limU⊥→IU⊥γ}.
Thus, we can assume Uγ⊂{F(γ)=const}=S first surfaces with compatibility conditions
U⊥γ∩S0=∅ where S0=S\{ζ0} and ζ0
a singular point, further that U⊥γ is analytic close to S.
The movement Ue (elliptic), has Ue⊥ as “transversals”, Up (parabolic) has
Up⊥ of the same character as Up. For Uh⊥ (hyperbolic) we have
Uhγ⊂S and Uh⊥γ approximates S.
Further by the Fourier dual (Uh)∗≃(Ue)⊥. Correspondingly in euclidean metric
we have (Vτ)∗≃(Ve)⊥ where τ is translation and e is rotation.
We assume here (I)=(IHyp)⊕(IPhe) are
analytic functions, that is we assume (IHyp)∋γ→Jγ∈(IPhe)
preserves analyticity.
Thus, we have Ue→Uh⊥
where transversal lines can be traced by translation, Ue⊥→Uh first surfaces
(multivalued) can be traced through planar movements.
However we do not have that Uγ∈(IHyp) implies U⊥γ∈(IHyp),
further we do not assume
U⊥γ⊂(IHyp)⊥ or V⊥Jγ∈/(IPhe). We define J
through L(γ,U⊥γ)=0 implies E(Jγ,V⊥Jγ)=0. Thus, L(Uγ,U⊥γ)≡0
for every γ. We use <,> to denote respective scalar products.
For a regular (reversible) movement (axes ∈/Hm) we have that \big{[}<\big{[}I,U\big{]}\gamma,\xi>=0\Rightarrow\xi=0\big{]}
implies U=I. In particular, if <(U−U⊥)γ,ξ>=0 implies ξ=0 then U=U⊥
that is we have points in common. Through the compatibility condition, we can assume points in common
on S. Note further Δ is joint for γ,Jγ.
Given that the joint points can be defined through limU⊥γ=limUγ (with orientation)
we see that tUU⊥−I≡0 in limes. Given Uγ∈Σ={F(Uγ)=const},
by reverting the orientation for U⊥γ the continuation Uγ−U⊥γ
can be taken in the sense of Cousin ([3]). We can assume product topology for Uγ,
the continuation using J is continuous and in L1 (with respect to the boundary measure).
If tUγ=U⊥γ except for a discrete set we can regard U⊥γ
as a continuation of Uγ. Note that we have existence of γ with Uγ=Iγ
implies existence of γ′ such that U⊥γ′=γ′ with γ=γ′.
Thus U⊥Uγ=IUγ
and UU⊥γ′=UIγ′ that is on invariant points we have \big{[}U,I\big{]}=\big{[}I,U\big{]}
(for instance Uγ=γ′).
Further <Uγ,U⊥γ>≡0 iff <γ,tU⊥Uγ>≡0
why tU⊥U∈∘(I) (annihilators). The movements are primarily considered
in H′, though using the moment problem, if the movement is analytic in a set E0, it can be
continued to C, assuming the compatibility conditions above.
Assume orthogonality is defined by
<f,g>=If(g)=0. We then have that N(If) is defined for g∈H, if f has regular
kernel. If N(I⊕I⊥)={0}=N(I)∩N(I⊥), we can write
V∪V⊥=Ω and V∩V⊥={0}.
When two mirrors are used, we get a non-commutative group. Consider the reflection
S=(S1,S2) through the diagonal
±x=y, R through the real axes and T through [math]. Note that the diagonal has two
generators S1,S2 and
RS1=S1R. But we have that RS1=S2R and TRS1=RS1T.
Thus tT=T,tR=R and
tS1=S2. For z→z∗ we have that TRS1=RTS1=RS1T=TS2R=S2TR=S2RT. That is z∗=−iz. Note that for harmonic conjugation that for a closed form
φ, if φ∗=−iφ that φ=αdz, where α is analytic
locally.
A joint boundary for (I1),(I2) is represented using first surfaces
Σ={F(Uγ1)(ζ)=F(γ1)(ζ)} for every movement U and
Σ′={F(Vγ2)(ζ)=F(γ2)(ζ)},
for every movement V and Σ≃Σ′. Thus, where
Jδ:γ1→γ2 and JδU=VJδ
we assume F(JδUγ)=const. for all δ→0. Consider the compatibility
condition F(V⊥γ2)=0, for some V⊥ close to and at distance from the boundary.
V⊥γ2=JU⊥γ1 is defined so that F(V⊥γ2)→Σ′
iff F(JU⊥γ1)→Σ′ regular. This is interpreted as two-sided,
that is the invariance principle in this case is extended with a compatibility condition.
Involutive movements**.**
Any movement on the hyperboloid is involutive. In our mixed model, any involutive movement in euclidean
metrics, has a correspondent movement on the hyperboloid. Orthogonal movements, are not necessarily
involutive, but our invariance principle maps U⊥→V⊥ uniquely.
3.1 The lifting operator
Consider L(Ux,y)→E(Vx.y), where E denotes the euclidean metric, through
the invariance principle. Define {Vx}⊥={y=Rxy⊥Vx}
or <Vx,y>=R(Vx), where R is defined using Radon-Nikodym’s theorem
and is specific for the movement. We define Vo={RR(Vx)=0}, a closed set
that is generated by V. Conversely, if L(tRUUx,x)=0∀x, which implies
E(tRVVx,x)=0∀x, where RUU=U⊥ and RU:X′→X′.
Thus, \big{[}L_{x},U^{\bot}\big{]}\sim\big{[}E_{x},V^{\bot}\big{]}
and over the reflection axes
J(U⊥)=(JU)⊥.
Using the condition that f and g have lineality in common, we see that we have a continuous mapping
{f−c}→{g−c}, through a planar (transversal) mapping.
In particular, with the compatibility conditions, we have sngf→sngg. Note that we assume logf,logg∈L1.
A reflection axes is defined by R1:trγ1=γ1. Given J:γ1→γ2
and Jtr1=r2J, there is a correspondent set for invariance r2γ2=γ2
that is defined by R2. For γ1, we assume symmetry with respect to R1. The corresponding
proposition for γ2, is dependent on ev and symmetry for v with respect to R2.
Using Radon-Nikodym’s theorem (tr1−1)γ1=0 and (tr2−1)γ2=0,
we then have (tr2−1)Jev=(tr1−1). Assume y=y(x) and consider
k(x,y)=xy.
Given k>1 and dxdy−xy>0, this implies 1<xy<dxdy (elliptic movement).
Given k<1 and dxdy−xy<0, this implies dxdy<xy<1
(hyperbolic movement).
Assume r2dγ2∼dr2γ2, we then have
rdγ1r2dγ2=ev or r(X1,Y1)r2(X2,Y2)∼ev
where dtdγ2=(X2,Y2). Given k(X1,Y1)k(X2,Y2)=const
and X1<Y1, we have that X2<Y2 and so on. Note that γ2 can be seen
as a continuation of γ1⊂(IHe)⊥. Given Jr∼tr2ev
and <rγ1,γ2>=<γ1,r2γ2> and <rγ1,γ2>=<tr2γ1,γ2>
that is r∼tr2. Assume A an annihilator for (I1) and B an annihilator
for (I2), both closed operators. For instance A=r−1 and B=tr2−1. We then have
(I)=(\mboxkerA) and (J)=(\mboxkerB). We have that if N(I)=N(J), given an analytic representation
of (I),(J), that \mboxrad(I)∼\mboxrad(J). For movements, if we have analytic representations of
both r,tr2 and r−1,tr2−1, then the geometric sets coincide.
Fundamental representation**.**
We assume given f analytic that γj are analytic and that the equation F(γj)(ζ)∼f(ζ)
can be solved in DL1′. When we can restrict the model to polynomial γj,
F can be constructed from f and the parametrices to γj.
In particular, where we have isolated singularities, we can represent F as a measure with compact support.
A very regular boundary is characterized by ([19]) singularities located in a locally finite set of
isolated points or segments of analytic curves. Particularly, when the regular approximations have isolated
singularities for some higher (finite) order derivative. When the model is considered in DL1′,
the real Fourier transform can be represented P(ζ)f~0(ζ) ([3]), for a polynomial P
and f~0 very regular. The fundamental representation can be derived in several ways. The parametrices
to hypoelliptic differential operators are very regular in the sense that the Schwartz kernel is regular outside the
diagonal. Assume for instance E a parametrix to γ(D)δ, where γ(ζ) is a hypoelliptic polynomial.
Then \big{[}E,\gamma(D)I\big{]}\sim\gamma(D)\big{[}E,I\big{]} has Fourier-Borel transform F(ζ)γ(ζ),
where F is \widehat{\big{[}E,I\big{]}} and \big{[}E,I\big{]}=\big{[}I,E\big{]}, in this setting, when the parametrix is two-sided.
Note also that F(γ(D)φ)=E(γ(ζ)φ), when φ→1.
3.2 Reflections
All movements in (IPhe)⊥ can be represented as reflections. Singularities for
(IPhe) can all be related to the boundary. Every point on the boundary can be reached through
reflections in (IPhe)⊥ emanating from an “origo” on the boundary. If the points are
reached through planar reflection, then analyticity is preserved.
We can represent points that can be reached through hyperbolic movements (translation), parabolic movements (scaling)
elliptic movements (rotation) in the same leaf.
In cylindrical domains (order 0), the translations are parallel with one axes.
Pseudo convex domains are locally cylindrical at the boundary.
Given P,Q∈Hm (the web of the hyperboloid), we can prove existence of unique movement
P→Q, that corresponds to a unique (euclidean) translation P→Q.
If π is a plane through P,Q and R a line ⊥π implies a unique existence of a
rotation axes R∼PQ (line). R is not uniquely given by the movement,
we have ∞1 possibilities in VT, ∞1 in VR and ∞2 in
VL ([21]). However, given that R is a hyperbolic movement,
it has a unique representation as a (euclidean) translation determined by P,Q.
3.3 Distance functions
Concerning the invariance principle, assume dΓ=dx⊗dy, where dΓ denotes
the distance to x=y in γ1. We now have three cases dx/dy=const (dΓ=const)
dx<dy and dx>dy. The corresponding distance function
in γ2 can be induced according to
(J−1)∗dΓ ( pseudo distance.)
The normal is defined in (I1) starting with the tangent.
In the case where (I2), we have blow-up according to
df→f, why we prefer to start with invariant points.
On first surfaces where all points are invariant, we consider transversals
on the form V⊥γ.
Consider (I1)⊂(I2)⊥ and d=(v1,v2), that is product topology.
We assume Runge’s property for d(γ1−γ2)∼inf(v1(γ1),v2(evJγ1))
for v∈L1. Assume for instance evγ2=zev1(z)∼ew(z1)
and we have existence of η, such that w(z1)∼η(z)1, where
η∈L1. When f=eϕ, we obviously have \big{[}I,e^{v}\big{]}(e^{\phi})=I(e^{\phi+v})=\big{[}e^{v},I\big{]}(e^{\phi}).
Assume that distances are given by (v1,v2), we then have that for invariant points that
v2≤v1 for a hyperbolic movement, v1≤v2 for an elliptic movement. Assume
v1∣f∣≤1/v2, where v2 is algebraic and v1=const, we then have that
v2<1 for f∈CN and v2>1 for f∈DL1′
(finite order). As v1=const. we have v22∣f∣≤v1v2∣f∣≤C,
when v2≤v1 and v12∣f∣≤v1v2∣f∣≤C in the converse
case. When degv22=N, we have f∈CN. For instance, v1(x,y)=const
we have vx1(z)=vx1(z) and vx2(y−x)=vx2(x−y), that is we assume x fixed
and v1v2=v2v1.
We define v through movements JUγ1=Vγ2. Assume (d1,d2)
distances to the euclidean axes, that is d1<d2 on the reflection axes, implies V
translation, d2<d1 implies V rotation and d1=d2 implies V scaling.
Assume E0 with product topology and dμ⊥E0. The Runge property implies that
dμ⊥C. Thus, if we have separate invariance in x and y, we have
invariance in (x,y).
Concerning monotropy, we have a separate (pluri complex) condition that is represented by ϵ−
translation. For instance if v=\big{[}v\otimes I+I\otimes v\big{]}, it is sufficient that
\big{[}I,e^{v}\big{]}(f)=\int\big{[}I,e^{v}\big{]}(x,y)f(y)dy=\int(\int I(x,z)e^{v}(z,y)dz)f(y)dy=\int e^{v}(x,y)f(y)dy.
Assume for x fixed, G(f)(x)=∫ev(x,y)f(y)dy and for y fixed,
tG(f)(y)=∫ev(x,y)f(x)dx.
Thus <G(γ1),ϕ>=<γ1,tG(ϕ)>. Given
JUγ1=Vγ2
and Jγ1=γ2, which implies Uγ1=γ1 and this implies Vγ2=γ2.
Given γ1⊥J−1γ2 with F(Jγ1)=F(evγ2), thus if
Uγ1⊥Vγ2, we must have v=const on all invariant sets.
If we consider (γ1,γ2)∈(IHyp)×(IPhe),
we can consider an associated distance d=d1+id2.
In the case with a regular complement and γ1→γ2 with joint lineality,
if d2,N denotes the distance to the lineality for γ2N, we have d2,N≥d1,N.
Thus in the case when Ω\ΔN↓{0}, we have that d2,N↑,
as N↑.
Alternatively we can give
(x,yN)∈(IHyp)×(IHe). We assume d21 a pseudo distance
and also a distance.
Given the condition d1/d2→0,
when y→0, we have that d12−d22d1d2=d2d1−d1d21→0,
as y→0. Thus if d~2=(d1+id2)2, we have that
\mboxRed~2\mboxImd~2→0,
as y→0.
Assume π a line (axes for reflection) ={d1(z)=0} and d1(tz)=td1(z),
t>0.
If π is a plane, we can use a two-sided distance
function, for instance {d1=const}∪{d2=const}, that corresponds to
N(d1)∪N(d2)∼N(d1d2).
Concerning first surfaces to distance functions, given d2 algebraic (limit of algebraic functions),
when d2 is a distance, it is locally 1-1. Given Schwartz type topology, we can assume these first
surfaces have the same properties as the zero sets.
Assume S1={ζd1=0} and Σ1={γ1F(γ1)=const},
then γ1 is locally bounded, we have thus dΣ≤cdΓ(f), that is
dΓ=0 implies dΣ=0. Assume d1,Σ→d2,Σ.
If we assume Jδ continuous, we have dΓ=0 implies d2,Σ=0.
conversely, if Jδ−1 is continuous, we do not necessarily have d2,Γ=0.
3.4 Singularities
Δ is defined through translation in Ω, which corresponds to Δ={Iγ=γ}.
We define a neighbourhood of Δ with respect to a lorentz movement U→I
and U→U~ζ∈Ω. In the case where Uγ→Iγ0,
then we can regard a singularity as an isolated point on Δ, given that U preserves
analyticity (planar), the point is reached using Δ as a strict carrier for the limit,
that is it is of no consequence what neighbourhood we consider. We assume all through this article
that f(ζ)=F(γ)(ζ) and log∣f∣∈L1, that is the singularities
are given by log∣f∣ and are of finite order.
In the case with Ue elliptic, we have that ∣Vef∣=∣f∣, that is
these changes of variables do not affect the singularities. In this case, the singularities on ∣f∣=1
can be seen as isolated and are completely defined by transversals. In the case where \mboxRef⊥\mboxImf,
we can start with an arbitrary point on ∣f∣=1, and approximate the singularity
by elliptic rotation, that is Ue such that ∣Vef∣=1 and V~eζ=ζ0.
Given ∣f∣2 analytic (does not imply f analytic), we can assume Ω={ζ∣f∣=1}
connected (\mboxImf∼\mboxRef).
Consider the movement as a functional and VeF(γ)=F(tVeγ)∼Vef.
Then <Veγ,γ>=1 implies <γ,tVeγ>=1, that is we can
assume tVe rotation (given a normal model).
Concerning parabolic movements Upf=F(tUpγ) and xy=xy=ρ
and y=y(x), tUpy=y. We are considering Φ(xy)=(tx,ty) for t real.
It is for this reason sufficient to consider singularities that are given by η(x)=y(x)/x,
where η is algebraic iff y algebraic. Note that {η=dxdη=0}⊂{y=xdxdη=0}
We have that xdxdη=0 iff dxdy∼−x/y ([3])
Note if (x,y)→(x′,y′) with dxdy=dx′dy′ and y′(x)=y(αx)=tAy(x),
then if tA=A, dxdtAy=Adxdy implies assuming tA=A,
dxdtA=0.
For translation Vhf=F(tVhγ), in the moment problem,
assume that A defines regular approximations and Vhγ
defines a movement on the first surface to f. Then,
∫Ad(Vhγ)=∫Adγ, that is A is not dependent on Vh.
In this case the singularity is not
affected by Vh. If F is linear and F:const→const,, we can assume
{F(Vhγ)=0}∼{F(γ)−λ′},
that is first surfaces to analytic functions, with regularity conditions as with ([16]).
In particular, when λ→λ0, there are Vh such that
Vhγ→γ0.
For V~hζ we can compare with Abel’s problem ([12]).
Given isolated singularities, we can assume V~hζ=ζ+η,
for some η.
Concerning the two mirror model, we consider A→γ1→γ2→B
where A,B are situated on first surfaces to f. In the planar case, where ∣γ1∣≤1,
∣γ2∣≤1 and γ1⊥γ2, then every B can be reached,
independent of starting point A on a first surface. Thus in the planar case,
every pair of points on the first surfaces, can be combined using a continuous path.
Consider U→V∈(I2)′ and (I1)⊂(I2)⊥, that gives
a continuation ϕ of γ1, that is <ϕ,γ2>=0. Further
<Vϕ,γ2>=<ϕ,tVγ2> defines
tV∈(I2)′ and tVγ2=γ2 iff
Vϕ=ϕ
and the invariance principle is here considered in DL1′. Assume
J:U→V and F(JUγ)=tJF(γ).
A chain given by U is mapped by J onto a chain given by V.
Concerning algebraicity, assume ∣f∣<C∣P∣ in ∞, where P is polynomial,
then for P to serve as a weight in DP′, it is necessary that I≺≺P.
We then have that P1≺≺P2 implies DP2′⊂DP1′
which corresponds to analytic functionals of finite type. In particular, for a reduced polynomial, we have
{P<λ}⊂⊂Ω and we assume (f/P) holomorphic outside a compact.
In the case where Wg=g/Q, that is QWg=g,
where Q is hypoelliptic, then W corresponds to a
very regular distribution, that is W∼I modulo C∞.
Singularities**.**
We assume all singularities for our model are on first surfaces to the symbol f and can
be reached through involutive movements, movements linked to movements orthogonal to involutive movements or algebraic
approximations.
4 Invariant sets
Consider F(γ1→γ2) with γ1⊥γ2. Assume
Φ:F(γ1)(ζ)→U1 and in the same manner
Φ:F(γ2)(ζ)→ζ∈U2.
Assume Jγ1=γ2. The problem is now under which conditions on J,
do we have that there existence Φ, such that F(Jγ)(ζ)→ζ continuous.
Sufficient for this is naturally that F,J are analytic, why Φ is continuous. This is however not necessary.
Assume γ1 has a desingularization U1=∪1NSj, where Sj are connected. We
can now define J on the covering Jtrjγ1=trjγ2 (rj is restriction).
Note that when γ2∣S1=γ2∣S2, we do not necessarily have
γ2→ζ uniquely. The condition trjJ=Jtrj,
means that J is not 1-1. For every γ2 partially hypoelliptic, naturally there is a γ1 hyperbolic,
such that Jγ1=γ2
Monodromy f(ζ)→γ is necessary in order to separate γ1 from
γ2. Assume γ1→Sj and γ2→S~j and
J:γ1→γ2, if we have id:Sj→S~j continuous,
we can define γ2 on Sj, that is on the covering to γ1. More precisely,
if Ω is a covering defined by γ1, we consider this as a domain for γ2,
that is {γ2~}=∪(Sj~,γ2(Sj~)) with analytic continuation and we write
γ2(Ω)=γ2~(Ω). Concerning localization, starting from
F(γ)→γ1→γ2→V, if V is accessible from
γ2, it is not necessarily accessible from γ1, further accessible from
γ1→γ2 does not imply accessible from γ2,γ1 or
F(γ). Further, if F(γ)→ζ is not continuous, there are possibly γ~, such that
F(γ~)→ζ is continuous.
Assume F=Ef, where E is a very regular parametrix to γ2 and F1(γ1)=f, then we must have that
F(γ2)=f, modulo −∞ action. Thus, if f→f0, we have E(f)→f0
modulo −∞. E can be chosen with one-sided support, assuming γ2 algebraic. When E
is constructed using Fredholm operators, γ2∼E−1(φ), as φ→δ.
Note that {γ2≤λ}⊂⊂Ω, where λ is a constant and Ω a domain
in Rn.
Assume, for an analytic quotient, (F2/F1)(γ)→0 over ∣γ∣=1 with positive measure,
we then have F2⊥F1 on ∣γ∣>1. More precisely
(F2/F1)(rT′γ)(ζ)=(F2/F1)(γ)(ζT) with ∣rT′γ∣=1.
Define E={ζT∣γ∣=1(F2/F1)→0}.
Thus, if (F2/F1)(γ)(ζ)→0 for large ζT, that is F1⊥F2
with respect to ζ and ∣γ∣=1, we then have F1⊥F2 with respect to γ.
Write (F1⊥F2)(ζ), when the orthogonality is taken in ζ, we then have
(F1⊥F2)(ζ) implies (F1⊥F2)(γ). In the same manner, if F
linear in γ, we have Δ(F)(ζ) defines Δ(F)(γ).
Assume f(ζT)=F(rT′γ)(ζ), where rT is assumed closed and locally 1-1,
why rT′ is locally surjektive. Define the continuation through rT′ and
<γ2,rT′γ1>=0 or <γ2(ζT),γ1>=0, note that the proposition
that rT′γ1=γ2⊥ is equivalent with the proposition that γ2(ζT)
is locally 1-1 at the boundary. Note that hyperbolicity assumes a Cartier boundary, while hypoellipticity
assumes a bijective ramifier.
We can define rT′(I)=(I)(ΩT).
Concerning accessibility, if for instance γ1=rT′γ2, with rT′→rT
locally 1-1 and closed (continuous), we have that rT′ is surjektive ∼J−1, that is
∀γ1, we have existence of γ2, such that F(γ1→γ2)(ζ)
solves the lifting problem. We can assume that J(γ1⊥γ2)(γ) induces a continuous
mapping J~(γ1⊥γ2)(ζ), that involves a complementary set to Ω.
Assume γ2=Jγ1, where we assume J~:N(γ1)→N(γ2).
If we using Radon-Nikodym’s theorem and let F(evγ2)=F(Jγ1), that is
F∘ev∼F∘J, where v∈L1. Then the condition logJ∈L1 implies
algebraic singularities. J is here defined as dependent on the movements, that is we write vjj=1,2,3.
Note that invariant sets are not necessarily preserved under iteration of symbols.
The sets Δ (lineality) and ⊥ orthogonality can not be assumed independent for (I1)⊥.
Consider for example f=f1+if2 and
f12−f22f1f2=f2f1−f1f21=v−v11,
implies f2f1→0, when the quotient above →−0 and
f1f2→0, when the quotient above →+0. Further let
eϕ=f1/f2, we then have \mbox{ sinh }\phi=\frac{1}{2}\big{[}e^{\phi}-e^{-\phi}\big{]},
that has →∞ as ϕ→∞ and →−∞ as
ϕ→−∞. Further, 1/\mboxsinhϕ=\mboxcschϕ that has
→−0, as ϕ→−∞ and →+0 as ϕ→+∞.
For a hyperbolic symbol, we have that f/Prf is real ([5]). Let f1/f2=pm1/pm2, where pm are highest order terms.
We then have that pm(tx)=tmpm(x), why if we choose x such that pm1(x)=0
and pm2(x)=0, then we must have f1/f2(tx)=const, as t→∞,
why it is characteristic for hyperbolic symbols, that the real and imaginary parts are not orthogonal.
Assume fN=eϕN, with dxdϕN→0 in the ∞, that is dϕN⊥dx
in ∞.
The condition x1ϕN(x)→0 as x→0, implies that ϕN→0
faster than 1/x goes to ∞, why the condition in ∞ implies a condition at the boundary. Assume ϕN+pN=I,
that is an algebraic complement. In this case we have ϕN∼I−pN, that is invertible outside
constant surfaces to pN, which gives possibility for two-sided limits. Constant surfaces for
ϕN are constant surfaces to polynomials. An algebraic transversal implies oriented first
surfaces (one-sided orthogonality). On the other side
if dϕN+pNdx=0 then we have dxdϕN=−pN(x) and when pN are
reduced, we can assume pN(x1)∼qN(x)1, for polynomials qN.
Note the example F(x,y)=ϕ(x)ψ(y), where ϕ=ϕ1+iϕ2 and ψ=ψ1+iψ2
We then have F1⊥F2 if ψ1ψ2+ϕ1ϕ2/1−ϕ1ψ1ϕ2ψ2
that is if we have separately ⊥ we have ⊥.
Given analyticity we have γ~∈(I)(Ω)=I(Ω~)=I~(Ω),
where we assume γ⊂γ~ implies Ω~⊂Ω.
Further, F∈DI~′⊂DI′, thus given that the continuation is allowed,
we have that the restriction is well-defined. Assume invariance is defined by {γF(ϕγ)=F(γ)}
for a transformation ϕ. Define Ω(2)={γF(ϕγ2)=F(γ2)},
it is then significant if ϕγ2=γ2
and V2={γF2(ϕγ)=F2(γ)}. Consider Ω′={γdF(ϕγ)=dF(γ)}
that is {tϕdF(γ)=dF(γ)} and Ω′′={dF2(ϕγ)=dF2(γ)}.
Define (J1)={γtϕdF(γ)=dF(γ)}, for F fixed.
It is significant if tϕ is linear, when we study Ω=Ω1∩Ω2.
(J1)⊂(J2) implies Ω2⊂Ω1 according to algebraic geometry
and (J2)′⊂(J1)′ according to functional analyse.
We can if F2 is linear over dγ,
conclude ϕdγ−dγ∈\mboxkerF2. If F(0)=0, we have \mboxkerF⊂\mboxkerF2.
Assume that Δ defines a geometric ideal (I), that is g∈(I) implies τf−f=g,
for some f.
Assume that Ωj gives invariant sets, then we have that Ω1∩Ω2→(I1)+(I2).
Sufficient for a disjoint decomposition is that (Ij) are given by positive functions.
Consider f∈(I1) and f=f+−f−. We have that {0}⊂Ω1∩Ω2
implies (I1)+(I2)⊂(J), where (J) is the ideal corresponding to a disjoint decomposition.
Assume f2/f1=φ and M(ϕ)∼φ (arithmetic mean), then the proposition that ϕ is harmonic corresponds to,
dzdf1f2 real and analytic. When dzdf1f2 real,
we have f1f2dzdlogf2f1=dzdloglogf2f1.
Thus, if logφ∈L1 and dzdloglogf2f1
is real and analytic, then we have existence of ϕ harmonic, such that M(ϕ)∼φ
is constant. Define F(eφ)=F(φ) and (FS)(φ)=S(eφ)=Sexpφ
and (F−1S)(φ)=Slogφ. We then have
(logf1f2)=FIlogf1f2=FF−1If1f2∼f1f2
Thus the condition logf1f2∈L1 using the Lelong transform,
can be interpreted so that f1⊥f2 (one-sided).
Note that in the model in this article, an algebraic continuation of an hyperbolic operator
is not hyperbolic (and vice versa). Note that if the ideals are given by distance functions d1,d2⊥,
such that d2⊥/d1→0 in ∞ and d2⊥/d1≤∣γ~∣,
where γ~=Jγ, which does not imply d1≤∣γ∣.
Existence of N, such that P is hyperbolic in the direction N, implies that P is not hypoelliptic.
Since the principal part pm to a
phe operator, is independent of some variables, we have that there exists N where P is hyperbolic
(in dependent variables). Thus the restriction of (IPhe), can in this way be a subset of (IHyp).
More precisely, given (I)=(IHyp)⊕(IPhe), when (IHyp) is seen as an extension of
(IPhe), there is a corresponding restriction to dependent variables for pm, as the domain
for (IHyp). Consider tk1f(tx)→Prf(x), as t→0,
where k is the order of zero. Particularly t−Nf(tη)=Prf(0)∀N and
tη∈Δ, that is an “infinite zero”. For a reduced operator, we have thus
tNf(x/t)↛Prf(0), for ∀N and t→∞.
Reduced operators are of real type (type 0) and modulo C∞ we can always assume real type.
Assume that S1⊥={ normals to S1}=N(f1⊥+f2), where Sj are first surfaces.
The condition S2∩S1⊥=∅ implies S2⊥∩S1=∅.
Further (f2+f1⊥)⊥=f2⊥+f1⊥⊥. The mapping S2⊥∩S1→S2∩S1⊥
is a mapping between layers.
Consider the first surfaces to the iterated symbols and M a retraction neighbourhood of Sj.
If we assume that Sj stratum, we assume an embedding Sj↪M,
that is given a stratification {Sj}, we assume
S1↪M→projectionS2, which gives a mapping between S1 and S2.
Assume S12⊃S1 and assume the same conditions for S2, consider
S12→S1↪M→S22→S2,
and assume the compatibility condition, S22∩S2=∅ or S22⊃S2.
The condition that f2/f1 is polynomial in the infinity, is necessary to come to the conclusion
that the intersection ⊥ is discrete (for instance [11]). The condition is also necessary to conclude that
the condition ⊥ is independent of ζ when ∣ζ∣≥R, R large. When Δ(2)⊂Δ(1)
(index refers to iteration) we have for the first surfaces that intersect Δ, that
S~1⊂S~2.
In the two systems we assume the lineality is the same,
it is characteristic for (I1) that S1∼S12. According to the compatibility conditions,
assuming S→S~
we can assume S~1⊂S~2 or S~1∩S~2=∅
Assume γ1→γ2 with the corresponding first surfaces Sj and
S~j, where we assume γ1→γ2 continuous and γj analytic,
that is we do not necessarily have existence of Sj→S~j continuous.
For the problem of continuing a desingularization to γ2, it is sufficient to assume γ1→γ2
locally 1-1. Alternatively, if we define Sj through a distance function d1,j and in the same
manner for S~j and d2,j, we can define d1,jd2,j and a ramifier rT′
from Sj to Sj~. Injectivity for rT′
is regarded relative d1d2=0. We assume Schwartz type topology according to ([15])), inclusion
of ideals I1,j⊂I1,j+1 is defined through d1,j+1/d1,j→0.
This implies surjectivity for an approximating sequence.
Thus, the condition γ1→γ2
continuous, linear and locally 1-1, is sufficient for existence of path Sj→S~j.
Continuation by continuity**.**
A sufficient condition on J:γ1→γ2 continuous, to induce a continuation
of the correspondent first surfaces, is that J is continuous, linear and locally 1-1.
Note that this property is not necessary for a global mixed model, that is f(ζ)→γ1→γ2→V,
for a given geometric set V
5 The two mirror model
We discuss the mixed problem in a two base (two mirror) model, that is we consider f(ζ)=F(γ)(ζ),
where γ∈(I)⨁(I)⊥. Assume Jδγ1→γδ∈(I1)⊥,
for a parameter δ→0,
then given F(Vγδ)−F(V∗γδ)∼0, where V is a given movement,
the limit V→I exists as two sided. Further, When F∼GH and F(γ1,γ2−1)∼∫G(γ1,μ)H(μ,γ2−1)dμ, when μ→δ0, then the two
mirror model goes over into a one mirror model and we have F∼(G⊗I)(I⊗H). Assume
the boundary Γ can be given by one single function η=y(x)/x (order 0). Denote η1∗∼V∗η1
reflection through V=I, then we have in the two mirror model, (η1∗)∗∼η2−1.
Assume <Uη1,η2>=<η1,Vη2>=0 and μη1=U∗η1∼V−1η2
and we assume η1=η2, over μ and Δ. Then μη1→η1
and μ−1η2→η2, that is tμ=μ is involutive. When
μ→δ0 we have η1(0)=η2(0). Otherwise, we assume \mboxsuppμ=Δ.
When F is symmetric over the path, we have that V is involutive relative F.
In the system (η1,η2), when we consider Δ→μ,
then η1=η2 can be regarded as an abstract light cone, that is η1×η2∼μ.
Concerning the
boundary condition F(η2)∣t=0=F(η1) and dtdF(η2)∣t=0=dtdF(η1).
In particular, when dtdF=dxdFdtdx+dydFdtdy=−Y2X1+Y1X2=0,
we have X2Y2=X1Y1 according to the Lie’s point transform.
For the lifting operator we use an involutive condition,
that is if ♯F is the continuation of F according to γ1→γ2,
we assume dxdFdyd♯F−dydFdxd♯F=0
in a neighbourhood of Δ, which implies Lie’s condition as above.
The lineality for the composite kernel can be represented as \big{[}G,H\big{]}(\xi+it\eta)=\big{[}G,H\big{]}
and ∫G(x,y)H(y,z+itη)dy=∫G(x+itη,y)H(y,z)dy. Thus, if \big{[}G,H\big{]}=\big{[}H,G\big{]},
then \Delta(\big{[}G,H\big{]})=\Delta(G)\cap\Delta({}^{t}H). If G has Δ(G)={0}, the same holds for
the composition, only assuming symmetry.
Further that if G=G1G2 with G1 hypoelliptic and N(G1)=N(G2), we do not necessarily have that G is hypoelliptic,
since GG′=G1G1′+G2G2′, where only one term in
the right hand side is assumed →0.
Two mirror movements**.**
The two mirror model refers to an involutive movement, using two reflection points. A generalization
to the use of two bases γj, requires localizers Fj with one-sided support j=1,2. A necessary
condition for the two mirror model, to give a normal model, is that one of the limits is independent of orientation.
Given a reflection in the plane with reflection points on the axles, assume that
the distances from B to A is given by d1,d2,d3. We then have
d3→0, z→A and →∞
as z→A′. Further d2→0 as z→A′, →∞
as z→B′.
Finally d1→∞ as z→B and →0 as z→B′,
that is d11→0
as z→B and →∞ as z→B′.
Note that d1 does not necessarily define a distance.
5.1 Orientation of limits
Given a simply connected domain Ω in the plane, then
we have that a simple Jordan curve Γ divides Ω into two connected components.
Assume Γ is a simple curve that is transported in a normal model along the transversal.
If V1,V2 are two sets intersecting the transversal, considered as “antipodal”,
we do not necessarily have existence of a unique plane between V1,V2, that intersects
the transversal. However according to Nishino ([16]), if V1,V2 are first
surfaces with constant values c1,c2 and if c1<c2, we can determine the intermediate set
as a first surface to a scalar c, c1<c<c2.
Assume dj distances to respective set and
consider <dj,∣f∣>, then if we assume d1/d2→0
in ∞, we have a continuous injection between respective spaces, weighted with
the distances. The relation defines a topological inclusion between respective ideals.
More precisely, under the condition d1/d2→0 in ∞, we can form
Ld2,Ld1,
that is Ld2⊂Ld1. Thus, Jγ1∈Ld2⇒γ1∈Ld1.
Further ∫d1∣J−1f∣≤∫d2∣f∣.
Assume η=y/x∈B˙, we then have existence of F∈DL1′
such that F∼P(D)f~0, where f~0 very regular. When we have
η∈B, we assume existence of η1∈B˙ ([3]), such that η∼mη1.
Note that when η2 corresponds to γ2, if we have η∈B˙ or 1/η∈B˙,
we have η2∈B˙. Existence of limits in DL1′ can be seen
as a topological type (A) condition ([17]). Note that when we do not have existence of limits F(η21)
in DL1′, we have existence of limits F(η2⊥) (annihilators).
Consider F(γ1→γ2)→U2 and F(γ1→γ3)→U3
given U2⊥⊃Δ(γj), j=1,2. When rTζ is locally 1-1 and
closed, we have that rT′γ is surjective. Thus, for every γ2 we have existence of
γ1 such that Jγ1=γ2, thus starting from Δ we can always find
a homogeneous symbol with Δ. Further, when F(γ1→γ2)→U
and F(γ1→γ3)→U, then γ2=rT′γ3,
that is we have existence of μ, a continuous path between γ2 and γ3. Thus the fact that we have
existence of an approximation of U, does not exclude existence of a longer path with the same limit.
In applications, the paths may have different order of zero’s, thus different quality properties.
Starting from the moment problem and Jγ1=γ2, given γ2 a polynomial, we
have that liminfγ2≤γ2≤limsupγ2, for the restriction to lines. For instance when f is
of type (A), as long as F(γ1→γ2) preserves this inequality and with finite limits,
we can solve the moment problem. When the limits coincide, the solution is unique.
Twosided limits**.**
Given γ1 from A to A′ (reflection point), γ2 from B to B′ and A′∼B′.
We refer to this as a two-sided limit. When γ2 also gives a path from B′ to B, the composition
gives a path from A to B.
We can divide two mirror model into RF(z)=F(z) and SF(z)=F(iz), that is we assume the reflection
points on the real axes or the diagonal.
When we do not have symmetry according to F(z)=F(z),
we must consider f(z,z). In the same
manner if F(iγ)=iF(γ) or rather (F+iF∗)∗=−i(F+iF∗) (pure), we can
refer to this as a transmission property, otherwise we must consider F(z,iz) (or F(w,w∗)).
Assume in the two-mirror model, that L is the segment between γ1 and γ2 and
consider F(\gamma_{1}\rightarrow\gamma_{2})=\int G(\gamma_{1},L)H(L,\gamma_{2})dL=\big{[}G,H\big{]}(\gamma_{1},\gamma_{2}).
Given F invariant for change of orientation, this corresponds to one-sidedness (with respect to two
mirrors). If L⊥γ1 and L⊥γ2, that is defined for instance by the distance
functions, we then have existence of L∼γ1×γ2,
where L is assumed to have points in common with γ1,γ2.
5.2 Wellposedness
Every movement in (IPhe)⊥ can be represented as reflection ([21]). This means that we have that
γ1∈(IPhe)⊥ and F(γ1)=const, can be reached through Uγ with
γ∈(IPhe)⊥ and given by reflection relative an axes R (not unique), that is U=UR.
Assume compatibility conditions, F(U⊥γ)=const, for the
approximation and assume that there are points in common, but U⊥γ is not necessarily in (IPhe)⊥. Given that γ∈Σ(S), a first surface,
we have that the reflection axes is a part of Σ(S). Thus, if R⊥ is the
reflection axes to U⊥ as (an euclidean) ⊥ to R, it can be used as a regular approximation.
F. and M. Riesz theorem: assume f(z1) analytic and bounded with
∣f(z1)∣<M for ∣z1∣<1.
Let E={f(eiθ)=limr→1f(reiθ)=0}.
Assume the measure for E is >0, on ∣z∣=1, we then have
f≡0 for ∣z1∣<1 ([4]).
Assume Σ={γF(γ)=const} equipped with a norm Σρ={γρ(γ)=1}.
Application on my model, gives that if the segment μ exists
between γ1 and γ2 in the boundary Γ, forming a set of positive measure,
and if two solutions F1≡F2 on Σρ, we have that F1≡F2 on Bρ={γρ(γ)≤1}.
In this application, the boundary is continued with a transversal between the first surfaces. The continuation
principle ([15]) gives a representation of F as a distribution of the continuation.
Assume J1=Jx⊗Jy and assume <(J−J1)γ,Tγ>=0, ∀γ, implies T is the id-mapping,
we then have that J=J1. Note for γ analytic, we have γ=0 iff γ∣L=0
for every line L, that is we can consider a pluri complex formulation.
Note in this case if {Jγ1<λ} is semi algebraic locally,
we have that for instance {Jxγ1<λ} is semi algebraic.
5.3 Localisation
Assume η(x)=y(x)/x exact, then the ideal given by \mboxkery, can be represented with a
global pseudo base. The same proposition holds if y is reduced.
An ideal that is defined by τzϕ/ϕ∼m0
with τz compact, can be given a global pseudo base and when η>0 over an ideal, then
η is exact and the ideal has a global pseudo base.
Localisation problem**.**
Given F(γ0)(Ω), determine γ2 analytic
on V, such that F(γ0)→γ0→γ2 continuous, further γ2→V
continuous and γ2N∈(IHe), that is representation using reduced measures.
Assume {Ωj} a covering to γ0 and Ω. Given a point ζ0∈V
and Vk a component, if γ0∈(IHe)⊥, then we can give γ2 as a
continuation on components Ωj to Vk and <γ0,γ2N>=0. When we have
dμ2∈E′0, γ0 can be extended with zero over Vk.
Assume Fγ2=1 (invertible), where γ2 is a hypoelliptic symbol,
and F has representation with trivial kernel.
Assume \mboxkerFev={0}, where F(evϕ)=0
implies ϕ=0 or evϕ∈\mboxkerF for v∈L1. We assume
F(Jγ1)=F(ev1γ2)=F(ev1+v2γ22).
Thus, if γ22 is hypoelliptic, we have ev1+v2→0 in ∞,
that is Fev1+v2→0 and F↛0 in ∞. Then
log∣F∣+v≤log∣F∣, we have that the type for v≤0, that is of type −∞.
Note that if JU=VJ, then U,V do not behave algebraically similar, that is Uγ12=γ12
iff Uγ1=γ1, but when Jγ1=γ2, we do not have Jγ12=(Jγ1)2,
that is J is not algebraic.
Note that if f(x)=x1g(x1) and f(x1)=h(x)1, we have that
x=g(x)f(x1), that is f(x1)h(x)=1 and f(x1)g(x)1=x.
5.4 Algebraic approximations
The mapping F(γ)→γ→γ2→ζ, does not necessarily preserve the
order of [math] for the localisation. For the localisation, existence of order [math] regular approximations is
sufficient. Note that concerning τ→Ve using a contact transform, we have that the order of [math]
is preserved, but not the shape of obstacles. We will assume the boundary locally of order [math]
for some movement, that is it can be defined by a orthogonal movement locally. Assume F(U⊥γ)→c
regular and F(Uγ)≡c,
given that γ is polynomial, we have through the lifting principle, existence of (tU⊥F) with an analytic representation.
It is sufficient, that tU⊥F∈DL1′ with (tU⊥F)(γ)(ζ)
analytic, that is F∼F(ζ,ϑ) kernel in DL1′.
Assume {ζF(γ1)(ζ)=c1}=S1
and (Ic1)={γ1F(γ1)=c}. Assume dx1dF=−Y1=0
in ζ with S1∩{Y1=0} algebraic and the same condition for X1. Assume S1→S~1 a continuation
by continuity. Assume J:γ1→γ2=γ1⊥, where γ1⊥
is closed, given that we have existence of F−1 continuous, we have F→γ1→γ1⊥.
As {F−c}→0, we have γ1⊥→o(Ic) (annihilator). When γ1⊥
partially hypoelliptic, we have (γ1⊥)N locally 1-1 (downward bounded) which implies
ζ→ζ0, that is the limit exists.
For instance assume γ1∈(Ic)(S1) and γ2 such that \mboxsuppγ2∩S1=∅
and F(γ2)=const. If (I1)⊂(IHe)⊥
where (I1)={d1=0}.
Note that d2⊥/d1→0 defines a continuation of γ1, that is
(Ic~)={γF(γ)=cγ⊥γ2} and the “moment problem”
gives that (I1) has a continuation to (I1)⊥, assuming
algebraic singularities.
Assume Jδ:γ1→γ2, for a parameter δ→0,
such that (tJδF)(γ1)=c over an involutive set, that is Jδγ1∈F−1(c)∼(Ic).
Given type (A), it is sufficient to assume Jδγ1 a polynomial. If γ1⊥∈DL1′
which implies γ1⊥∼Pμ and Pμ(γ1)=μ(tPγ1)∼
algebraic continuation close to the boundary.
Assume the continuation is given by a movement,
such that (U⊥γ) and (Uγ)⊥ have points in common.
For instance U⊥γ→{F(γ)=c}=S1 regularly and F(Uγ)=c
and U~ζ⊂S1. Let V⊥γ=JδU⊥γ1, where we assume
{V⊥γ}∩{F(γ2)=c}=S~1 algebraic, this can be seen as a
compatibility condition (when v∈L1).
Consider for example F as an analytic function of γ, where the boundary Γ is defined as ⊥
movements, that is if Vγ is translation, and V=JU, we can assume
U⊥γ are parallel planar movements. Given a normal model, if the measure for
Vγ is positive and F(Vγ)=f(ζ), we have wellposedness according to a previous argument.
Note F(V⊥γ)=const, that is Uγ denotes a ∼ planar movement.
If R1 is the reflection axes and R2 the corresponding axes in euclidean geometry.
Assume R2~ the corresponding points to V~, that is Vγ=γ implies
ζ∈R2~, then if V−I has an analytic representation, this is a line.
6 Discussion on change of base
Assume f∈(I) and g∈(I⊥), we define H(g)=H(f)=0 (H=τ−1) on Δ, that is
H(f)=Af(H) and H(g)=Bg(H) which implies Af(H)=Bg(teφH) as
“inverse functionals”. Thus H(g)=H(eφf), where φ∈L1 in our model, which
corresponds to equivalent zero’s. Consider F(f+g)∼F2((f−eφg)+i(g+ieφf))
assuming F1⊥F2. Assume R(f)=eφg and R∗(g)=−eφf where J is reflection through Δ
and F(Jf)=F(eφg), that is F∼F2((1−R)(f)+i(1−R∗(g))).
Starting with V⊂Ω, and Ω\V analytic, we can form (I)(V)⊗(I)(Ω\V)
Denote by (I⊥)={gfg=0}, an annihilator ideal. The corresponding geometric set
is V∪Ω\V.
If we assume f,g positive, we have
N((1−f)(1−g))=N(1−fg), that is (fg)⊥=f⊥g⊥.
Assume instead (I)⊕(I⊥) with base elements f,g and F1=teφF2, where tφ→∞.
We then have F(αf+βg)=F2((1+ieφ)(αf+βg))=F2(αf−eφβg+i(βg+eφαf))
and =F2(αf−eφβg)+iF2(βg+eφαf).
Further, if α=β=1, f−eφgg+eφf=1−eφfgfg+eφ, why if fg→0 in ∞
we have that the quotient above →∞. In the same manner, if f/g→0 in ∞
faster than eφ→∞, the quotient →−0 in ∞.
Thus, we have that F1⊥F2 one-sided, given f⊥g one-sided.
Assume (I)⊥={g<f,g>=0} on a set of positive measure, then we have that \mboxsuppg=W
is the set where f is not a polynomial. That is, ∫Wfgdx=0 implies fg≡0 on W or that the measure for W
is zero and if W contains a connected set where fg≡0, we have that this set has measure zero.
If fg≡0 on a line L⊂Δ , this implies g a zero divisor. Assume τ′=τ−1
algebraic and τ′(fg)=τ′fτ′g with τf=f and τ′(fg)≡0, independent of
g. Assume now <τ′f,g>≡0 and <f,τ′g>=0. Define
Σ={<τ′f,g>=<f,τ′g>}.
If g is reduced, we thus have Σ={0}.
Assume (Jf)={g<τ′f,g>=<f,τ′g>\mboxonL} where
L has positive measure. We then have τ′−tτ′ is not algebraic!
We have that L⊂N(Jf) and IN(Jf)∼rad(Jf).
Assume γ1→γ2 defines a broken ray according to γ2∗−1≃γ1∗
thus γ1,γ2 must have a point in common. It is sufficient for this to assume γ2
has two sided limits.
Assume (γ2−1)∗≃(γ2∗)−1 which means γ1∗.γ2∗∼1
(Legendre). We denote this γ1∗Lγ2∗, γ1⊥γ2,
γ1Lγ1∗, γ2Lγ2∗, γ1∗Lγ2∗,
that is we can define ⊥→L continuous. Note that x.x∗+y.y∗∼1
assumes x⊥y, that is when γ1∗Lγ2∗, then we must have γ1⊥γ2. When reflexivity is given by γ1∗∗=(x1∗∗,y1∗∗)
we have that x1∗∗⊥y1∗∗.
Consider now, {ζdΓ(Y/X)=const} that describes parabolic movements.
When dΓ∼∣⋅∣
we have that dΓ(Y/X)=const implies Y/X↛0, that is Y/X=const is complementary to
Y/X→0 and conversely if Y/X→0 we have that dΓ(Y/X)=const.
Assume {γ2<λ}=M with γ2⊥(γ2)=0 implies γ2∈M
where γ2∈(I2) on a set V and we assume (I2) closed with (I2)⊥⊥≃(I2).
If we define (I1)⊂(I2)⊥ through d1,d2⊥, we have that (I1)
can be considered as closed in (I2)⊥ for instance d2⊥/d1→0 with
d2⊥(z)∼d2(z1)→0, when z→∞.
Note that if we assume d2(γ)→0 implies γ→γ0 where
γ reduced, we must have d2(ζ)→0 implies ζ→ζ0.
Consider the problem L(Uγ,Uγ)=L(γ,γ) and L(Uγ,U⊥γ)=0. An
axes L(Uγ,γ)=L(γ,γ) corresponds to an axes for U⊥ and L(U⊥γ,γ)=L(γ,γ).
If the condition L(Uγ1,ξ)=0 implies ξ=0, we must have U=id, that is γ1 on the reflection axes.
We assume ξ=0 implies Jξ=0 since J is assumed to preserve orthogonality, that is
L=0→JE=0. This condition is also assumed for the inverse J−1. Thus, if
E(Vγ2,Jξ)=0 implies Jξ=0, we must have V=id, that is a reflection axes in L,
has a corresponding axes for invariant points in euclidean metrics. In particular
H1(γ2)=<γ2,J−1γ2>
where H1(Vγ2)=<Vγ2,γ1>=<JUγ1,γ1>=H(Uγ1).
H1(Jγ1)=0 implies H(γ1)=0 and we can use that H1(Jγ1)=H(evγ1)
that is H:(γ1,L)→(γ2,E) (positive) linear functionals.
Given a reflection axes R to U, there is a reflection axes R⊥ to
U⊥, such that R∩R⊥=∅ (note that R⊥ is not unique).
Particularly, if γ(ζ)∈Σ, where Σ={F(γ)(ζ)=const},
we assume R⊥⊥R with points in common. We have that R⊥=R⊥(R), R⊥∩Σ={(x0,y0)},
for some R⊥. When F is constant on R, we have F=const on R⊥.
Consider V,V⊥∈H′ and use the topological isomorphism H′(E)→Exp(E∗),
where Exp are entire functions or regular with slow growth ([15]). Assume compatibility conditions,
such that V⊥γ2 regular for F or F(V⊥γ2)=const.. Then since
V⋅1=1⋅V, we have \big{[}V^{\bot},I\big{]}=\big{[}I,V^{\bot}\big{]},
over regular approximations. Further, we assume JI=IJ on the set corresponding to Δ. If
R⊥ is an axis for invariance for V⊥, we have an axis R to V
and R⊥≃R, further a line R⊥~ corresponding to regular approximations.
Assume for parabolic rotation τp that F(τpγ)=const, then over S={F(γ)=const},
dγdtτp≡0. Note that the condition
ϕ1′ϕ2′=cϕ1ϕ2
corresponding to elliptic rotation, that a1ϕ12+b2ϕ22=1,
for constants a,b. Define F(x,y)=F1(xy) and τe elliptic rotation,
we then have tτeF(x,y)=tτpF1(xy)
and F1(xy)=F(x(1,xy)) or tτeF=tτpF1.
In particular we consider the domain D(F), that is we can define D(F)=xD(F1)z1F(z1)=f(z) for 0<∣z∣<R.
Consider G(z,z⊥)=(G(z),G⊥(z)), where G(z),G⊥(z) are real. Using Tarski-Seidenberg’s theorem, if
{(z,z⊥)G<λ} is semi algebraic, we have the same for
{zG<λ} and in the same manner for z⊥.
Assume GG⊥=G⊥G, then G2∼G2−G⊥2+2iGG⊥. For the real part,
assume {G⊥G<GG⊥} bounded, this corresponds to G⊥2≺≺G2
in ∞. When the set is unbounded, we have that G⊥<λ implies G<λ in
∞. If limz→z0G=limz⊥→z0G,
we have that z0 is an isolated point. Note that it remains, given Uγ a movement,
to define U→U~ and γ(U~ζ)=Uγ(ζ).
Consider G(z)→G(z⊥)=G⊥(z) as a projection operator and assume
⊥, dependent of orientation, that is one-sided, then we have that {G<λ} semi algebraic
⇒{G⊥<λ} semi algebraic, can be seen as a transmission property.
Assume VJ=JU and J:p→q. Consider U→V∈(I2)′,
that is V is a functional over (I2). In particular when (V−I)γ=0
and Uγ1=γ1 implies Vγ2=γ2. Given (I2) is closed
we have that (I2)=(oI2)o. When (I2)⊂(IHe)⊥ with Runge’s property,
we can regard (I2) as closed in (IHe)⊥ (with respect to B˙).
The moment problem, for (I2)=E0 provides a continuation to C.
For instance, γ⊥=evγ with ev→0 (or ∞) and
F(γ,γ⊥)→0
where γ⊥/γ→0 in B˙, thus we have existence F1,
such that F(γ,γ⊥)=F1(ev).
7 Intermediate ideals
Define V1={x∈ΩF(ϕx)=F(x)}, for a fixed F, that is ϕx−x∈\mboxkerF,
an ideal of holomorphy. We assume here F linear in x, but it is not assumed linear in Ω.
Assume V1 is given by {f−c1}, where f is analytic and c1 scalars and in
the same manner for V2. Using the theorem on intermediate values, we can assume existence
of V between V1 and V2.
Assume (J) an ideal such that (J)=\mboxkerϕ1, for instance ϕ1=ϕ−1 and (J)⊕(J)⊥=(E), with {0}=N(J)∩N(J⊥),
that is ϕ1+ϕ1⊥=id (local identity).
Given that S1→S2 algebraic, we have type (A) first surfaces, that is we have a
lifting principle over an algebraic polyhedra ([17]).
Concerning existence of (I0) such that (I1)⊂(I0)⊂(I2)⊥.
Given that the inclusion is continuous (closed) and injective, the existence can be derived
using the theorem of intermediate values.
A sufficient condition (and necessary) for inclusion between weighted space in DL1′
is that quotient of the corresponding weights goes to [math] in the ∞. If in this setting
(I1) has the weight ρ1,
(I0) has the weight ρ0 and (I2)⊥ has the weight ρ2.
Then the condition for the inclusion we are looking for is
ρ2/ρ0→0,ρ0/ρ1→0 and ρ2/ρ1→0.
For the hyperboloid we have given a desingularization μ, that given F meromorphic
then F∘μ is holomorphic, we have a lifting principle over a desingularization.
Consider (x,y)→xy=η(x). We denote the diagonal V={(x,y)y(x)=x}.
Given y=y(x) analytic ∈(I) and η∈(J), we have where x=0, that (J)⊂(I)
and where x=const., V⊂{y=const}c. (J) is algebraic, if (I) is algebraic.
When y is linear, V is linear.
Assume x,η(x) does not have presence of essential singularities in the ∞ and consider
x(1,η)→(x,y), that is given η analytic we have existence y=y(x),
such that η(x)=y(x)/x. Given x reduced, we can represent
a global base.
Intermediate ideals**.**
Assume dv a measure on the boundary Γ that is joint for (I1) and (I2).
Define dμ1=ρ1dv and a corresponding functional B1(f)=∫fdμ1
and in the same manner for dμ2 and B2, with the condition that ρ2/ρ1→0
when we approach Γ. If we can find ρ0, such that ρ2/ρ0→0
and ρ0/ρ1→0 as we approach Γ, we have existence of a corresponding
functional B0, such that B2≤B0≤B1 and an ideal between (I1) and (I2).
Note that (IHyp)⊂(IPhe)⊥⊂(IHe)⊥. Further if we have existence of
α of bounded variation such that ∫Ωgdα=0 and dα reduced,
we have that Ω is a strict carrier to α ([15]), that is α
can be represented with compact support.
Assume dβ=eϕdα, where ϕ∈L1, here we associate ϕ to a hyperbolic
movement.
When ϕ is linear, we can define the continuation g→g~ using the Fourier-Borel duality.
Note that if eϕ→0 on a radius L, we have that eϕ→0
on a disc. In this case β can be chosen as summable.
Given existence of (I0) such that (IHyp)⊂(I0)⊂(IHe)⊥ we can chose (I0)=(IPhe)⊥.
Given a point and a normal in the point, if we consider a neighbourhood of the point with regular boundary,
then the boundary can be oriented. This corresponds to the concept of a pseudo vector ([10]).
The regularity conditions for dynamical systems and the corresponding conditions for first surfaces,
for instance the condition (N) ([16]), can be used instead with advantage. Thus we can replace
the concept of pseudo vectors for first surfaces and transversals, given that we assume the first
surfaces oriented. Note that this condition is necessary for the transversals to be algebraic.
Note the following problem: Determine a dynamical system corresponding to a hyperbolic system
such that γ in this system has normal n1 in p0 and with p0 a zero to the system.
We assume further n1 locally algebraic. In this case the regularity conditions indicate a pseudo normal orientation
([10]). In the same manner for n2 and a dynamical system corresponding to a partially hypoelliptic system.
Thus Δ→nj approximates singular points that are given by the right hand side.
When nj are locally algebraic, we have that γ is defined as locally analytic.
Assume dj the respective distance functions to the joint boundary (first surfaces) with d2
reduced, such that d1/d2 a distance.
Using that d1/d2<ϵ, we can use the type (A) condition ([17]),
that is assume S1,S2 first surfaces closely situated,
we then have that S1 intersects the normal in the same manner as S2.
In the same manner if λ⊥η2 and dtdλ=(X2,Y2).
We consider (X1,Y1)→μ(X2,Y2), as a continuation,
that is μT→dTdλ∣T=0
when T→0 and μT→(X2,Y2).
Assume now γ1∈(I1) satisfies a dynamical system (X1,Y1) and in the same
manner that γ2∈(I2) satisfies (X2,Y2). We argue that there exists a dynamical system (X,Y)
associated to (I). More precisely (I1)⊂(Ij)→(I2) such that Fj are
Hamiltonians corresponding to the approximating ideals (Ij),
that is (−dydFj,dxdFj) give the dynamical system we look for in limes.
We assume for this reason η⊥dxdFj and η⊥dydFj,
why assuming the conditions in Weyl’s lemma, η∈C1 and \mboxsuppη↓{0}.
In the same manner we can consider (I)⊂(Ij)→(I2) where again \mboxsuppη↓{0}.
In a discussion of desingularization, we note that if Ω1 is associated to (I1)
and Ω2 to (I2) we have that we only assume γ1→γ2 continuous,
why we can not establish Ω1→Ω2 as a continuous mapping. Note that a desingularization
is not established for non-hyperbolic operators.
Concerning MV(x,y)=logx−logyx−y ([24]), if rT′ is locally algebraic and
rT′y(x)=y(rT′x), we have M(rT′x,rT′y)=rT′M(x,y). Let
MV(x,y)=−xdxdηlogη(x)x(1−dxdy), where
η(x)=xy(x) and =xdxdη−y(1−dxdy),
without degenerate points in the denominator. Given that g=dxdeϕ, we then have
gG(g)≤gM(g)∼dϕdx, that is we have a lower bound
for the inverse mapping to the phase. If we assume fj=eϕj with ϕj∈L1 for j=1,2 and
ϕ2ϕ1→0, we have ϕ=ϕ1+ϕ2 and ϕ1⊥ϕ2,
which implies eϕ=f1f2.
In ([7]) we note Theorem 17, that is if a Dirichlet series
is summable through arithmetic mean, it is summable through logarithmic mean.
The proof is based on a discussion on the function (w−tlogw−logt)k−1=(L(w,t)1)k−1 that is increasing steadily from t=1 to t=w and the limit
as t→∞ is w1−k. Riesz gives a proof for k>0. For the converse result
(in general false), we refer to theorems 19,20 ([7]).
Consider now γ→η=y/x, then we have that reflection through γ→−iγ
can be written η→1/η and in the same manner reflection through the real axes, η→−η.
The condition on vanishing flux is then ∫βdF(η1)=0. Assume η2 denotes
continuation of η1 to (I1)⊥, such that η1∗∼1/η2. Assume
F(η1∗)=F∗(η1), we then have if F(η1)−F∗(η1)∼F(η1)−F(1/η2)∼0,
that F is symmetric over the continuation and we have a transmission property in this case.
Assume now G(f)=eM(ϕ) for f=eϕ and g=dxdf=eψ=dxdϕM(g)
that is gM(g)∼dϕdx. Assume ϕ,ψ sub-harmonic. Given a lower bound for
dϕdx, we can conclude that if ϕ→ϕ0, we see that x→x0.
Given 1≤dϕdx, we have that ϕ≤ϕdϕdx=z(ϕ1),
given x is analytic considered as a function of ϕ in 0<∣ϕ∣<∞. Given
z(ϕ1)→0, we have that ϕ→0, why we have existence of w,
such that w1(ϕ1)→0 implies ϕ→0, that is w1(ϕ)→0
implies ϕ→∞, why w is downward bounded. Thus we have where x is analytic,
a mapping x→w, such that w is locally 1-1, that is if w→w0 implies
ϕ→ϕ0, it is sufficient to consider the phase. Note that
if dxdϕ→0 implies x→0, that is
f′/f→0 implies x→0, then we have that f∈(IHe)⊥ for
all x=0.
8 The transmission property
8.1 The transmission property for summable distributions
Immediately, in the case when
F can be represented by a linear functional, we can define ⊥ using for instance annihilators.
If I(f)=δ0∗f we have that I reflects the support. If f has symmetric support we have that
I(f)∼f. If further f is proper, then I(f) has the same property.
Assume in particular Uj closed in some set Z, assuming Schwartz type topology,
we have that (x,φ)∈V×Uj is closed iff x→φ(x) continuous.
If singularities are approximated through transversals L, there are points in Z∩L
that do not belong to Uj. More precisely, if u0∈L∩Uj and
uj→u0, we have that uj∈Z\Uj.
Define F(Ix)=F(−x) and tIF(x)=−F(x), this can be seen as a weak definition of odd
operators. Thus if FI=IF we have that F is odd. If FI=F we have that F is even.
Note that \mbox{ supp }\big{[}I,E\big{]}=-\mbox{ supp }E. If E,F are both one-sided,
we may have that \big{[}I,E\big{]}\big{[}I,F\big{]} is one-sided
but \big{[}I,E\big{]}F\equiv 0.
In the terminology of oscillating integrals, F(x)=∫a(x,θ)eis(x,θ)dθ
where a(x,θ) are poly homogeneous, for x∈X and θ∈RN.
The phase function s(x,θ) is assumed real, 1-homogeneous in θ with
sm(x,θ)=0, as s=0. Assume S={sθ(x,θ)=0} closed and conical
and WF(u)={(x,θ)θ=sxsθ=0}. Using a bijection
φ, WF(u(φ(x)))={(φ(x),tφ′(x)θ)∈WF(u)}. Assume
x∗=ξ, η∗∼φ(x), why dxds(φ(x),ξ)=dxdφsx=φ′(x)ξ,
then we have η=dxdφξ and {}^{t}\big{[}\frac{d\varphi}{dx}\big{]}^{-1}\eta=\xi.
In particular ∫a(x,ξ)ei<x,ξ>−H(ξ)dξ∼(A/H) ([5]).
Note for the dual a′ to a polynomial, if a′−a≡0 on the radius in a disc,
we have that a′−a≡0 on the disc.
For a pseudo differential symbol a we must except the imaginary axes.
Assume that a has a symmetric kernel with respect to the imaginary axes, for instance
a′−a=Σjδ(j), where δ is assumed to have support on
the imaginary axes.
Given a very regular boundary and η2 reduced
we can consider 1/η2∈B˙, why (I1) can be seen in DL1⊥
that is P(D)f~0
is associated to 1/η2, which can be seen as a topological transmissions property.
8.2 The transmission property for two bases
The transmission property, when it is derived from involutive reflections U, implies
presence of a normal model. In the last section, we see that a global model does not imply a normal
model. If we can map bijectively a broken ray
onto a transversal, we have one-sidedness for one segment with respect to the first (x−) axes and one-sidedness
for another segment with respect to the second (y−) axes.
Now consider one-sidedness with respect to two planes, assume E(x,y) the kernel corresponding to
the first segment and F(y,z) the kernel to the last segment. Assume that we have existence of
a segment y→y′
(transversal) according dydy′=1. We assume again the segment normalised using distances.
We write G(y,y′) for the kernel corresponding to the middle segment.
In order to compare with one-sidedness, we assume G(y,y′)→1
as y→y′. Note that F is assumed symmetric after reverting the orientation
for the last segment.
If the composition is algebraic, we do not have that the factors are algebraic.
Assume we use distances to represent the convergence, let d1 be the distance
to ξ2=0 and d2 the distance to ξ1=0. When the distances are reduced we can assume the inverse
a distance, otherwise a pseudo distance. Assume A→A′→B′→B, where A,B on ∣ξ∣=1 and
A′,B′ on axes. Given symmetry for the kernel, we can assume d2→0 has a
reflection in d1−1→0.
If d1(ξ)→0 as ξ→0, then d11(ξ1)→0,
when ξ→0
that is ξ=1/ξ.
Let i(dj)=1/dj that maps distances onto pseudo distances.
If A∼B
(congruence) we can assume d1d2∼1. In particular d1=0 for z=A,
d11=d0=0 for z=A′, d01=d2=0 for z=B′ and d21=0,
for z=B.
In this case we have that d1d2=0 implies z=A or z=B′.
As d2d1=0 we have z=A or z=B. Under the symmetry condition for fλ=f−λ we have
{d1∣fλ∣<c}∼{d21∣fλ∣<c}, that is we can assume
fλ has algebraic growth at the boundary.
If we instead assume A singular in the sense that d1∣fλ∣1<c at the boundary,
we have that f is downward bounded at the boundary and {∣fλ∣<c} can be seen
as bounded. Simultaneously if B is regular, we have that the corresponding set is unbounded at
the boundary.
Consider f with algebraic continuation in {d1d21∣f∣<c}. We are assuming
f~(z,w), where z is the reflection of w.
Assume now z,w a continuation of path A→A′→B′→B.
Define instead d1→0 as z→A and d1→1 as z→A′
and d21→0 as z→B and d2→1 as z→B′.
We assume d0(A′)=d0(B′)=1, we have that d0d2d1∣f∣(z,w)→
[math] as z→A, 1 as z→A′, 1 as w→B′ and [math] as w→B.
Starting from a point at the boundary A, assume that we have existence of a path τ between
A and B, that does not contain any other singularities than A, in the sense that A can
be identified with a regular point B, we could represent A and B in the same leaf.
The points can be seen as isolated on the path. If not all points on the boundary
Γ are singular, we can always find a path to B, if all singularities are situated on the
boundary, we have that the path is regular.
8.3 General remarks
The condition logf∈L1 can be seen as log∣f∣∈L1, that is
∣f∣=∣f∗∣ is a symmetric condition. For selfadjoint operators, it is sufficient
to conclude hypoellipticity, to consider translation invariant sets.
Polynomial operators have solutions with one-sided support, that is we can assume F(γ)(ζ)=I(ζ),
where F=E and E has one-sided support, when
γ is polynomial outside the kernel to E. Thus we have for the continuation
γ1→γδ algebraic
that the corresponding Fδ can be selected with one-sided support.
Starting with F(e−vγ1)=F(γ2), with v∈L1, such that v≡0 over the
set Δ where γ1=γ2. Assume Vγ2∼η and η→η∗
reflection through the axes η=η∗, η=y/x. Assume v(η,η∗)∈L1 and note
that v=0 implies ∣η∣≤1 (≥1). Let H(α)=∫H(η,η∗)α(η)dη,
then for α∈B˙, we can assume H∈DL1′ a Schwartz kernel. The condition
v∈L1 means isolated singularities and we can assume v∼v1, where v1 is analytic.
When H∼mH1 locally algebraic, we do not have a normal model for H1, even when η→η∗
is involutive. However we have a global model according to the moment problem.
A global representation**.**
The representation F(γ1→γ2)(ζ)=f(ζ) and F(γ1)=F(evγ2),
with the condition that v∈L1(η,η∗), gives a global model. It is not necessarily a
normal model.
Note that v is defined by the movement. By considering w=v+v⊥, where v⊥ is defined
by the orthogonal movement and where both v,v⊥ are assumed continuous, if we assume the
compatibility condition w=0 on invariant points and on the
intersection of the supports to v,v⊥, we can obviously give a global representation for w.
The conclusion is that if the singularities are reached using w, we have a global base for the model.
Assume A=A∗ a hypoelliptic ps.d.o, then A has very regular parametrices, with trivial kernel.
Thus the parametrices to A have a transmission property modulo C∞, in the sense that the regularity
is symmetric with respect to diagonal. For a partially
hypoelliptic operator, we do not have a trivial kernel, but the Schwartz kernel has hypoelliptic
representation over kernel (zero space) and outside
the zero space ([3]). Obviously we do not have that the sum of kernel has the symmetric regularity property
Note that if we define ⊥ using g(x1)=0 on V∋0 (a bounded set)
we must separate between the case where g∼\mboxRef\mboxImf analytic
and the case where g≡0 in a disc-neighbourhood of [math]. When ⊥ is defined by
a rational function g we have that ⊥ is of order 0, Further, when g is analytic we have that
⊥ is Cartier.
8.4 Final remarks
Starting with the observation, that if φ is a closed form in the plane and φ∗ (harmonic conjugate)
with φ∗=−iφ, we have that φ analytic. A mapping that maps
(x,y)→(y,−x) is pure, that is preserves analyticity.
Assume L the line x=y (the light cone), then reflection through L can be seen as parabolic
movements. Assume L0 the positive
imaginary axes, L1 line x=y, x>0, L2 the positive real axes,
L3 the line x=−y and so on.
Assume c0(x,y)=(−x,y) that is reflection through L0 and so on. We then have that
cj+1cj(x,y)=(y,−x) that is pure mappings.
Further, cjcj+1(x,y)=−(y,−x) and so on.
Consider f1f2=φ1. Note that given W planar in OAD
([1]), that is we have existence of u analytic with finite Dirichlet integral,
such that u is constant on W.
We then have for every single valued function u, that u is linear. We can in this context consider
φ1 as a function of f. For instance φ1(f+g)→0
in ∞, when f1⊥f2 and g1⊥g2.
When a domain is defined by a distance d, the domain is said to be d− pseudo convex if
−logd is plurisubharmonic.
Note that dj(x)−dj(y)=0 iff edj(x)−edj(y)=0, ∣d(x)−d(y)∣≤d(x−y).
In particular, on the set where d∗=d and d2∼1 we have if d(f)=0 that
∣f∣=1 and dxdd(f)=0 implies f=1. Assume d>0 a distance on the phase space
to symbols, then we have
d(ϕ)=d(ψ) implies d~(eϕ)=d~(eψ), where d~(eϕ)=ed(ϕ).
When we have equality in the tangent space, we have eϕ=Ceψ. Further if d~
is locally 1-1,
we have that d~>0 where d>0. When d<0 we can consider
d~(f)d~(f1)=ed(f)−d(f)=1, that is d~(f1)∼1/d~(f)
and d~ can be seen as ”algebraic“. Note that this means that d corresponds to (f1,f2), d to (f1,e2),
−d to (e1,e2),
−d to (e1,f2), id to (e2,f1), id to
(f2,f1), −id to (f2,e1) and −id to (e2,e1).
We have in this case a two-sided solution f1e1=e1f1=1.
Assume A→B through reflection points s1,s2. Assume
21dd=21(d12+d22) defines the distance between
A and B. Given that the domain for dd
is connected and dd monotonous on the path, there is a μ between s1 and
s2, using the theorem of intermediate values. For instance if d1=1 in s1 and
d2=1 in s2, we have that 21dd=1 on the path between s1 and
s2. If d12,d22
are polynomial, we can consider a semi algebraic set and the path μ between the reflection
points as a part of the boundary.
9 The boundary
9.1 First surfaces
First surfaces are naturally invariant for all movements and existence of a regular approximation
outside the first surface implies existence of a V such that dTdV=0 over
this set.
More precisely, assume the first surfaces are defined by movements with the compatibility condition
U⊥γ⊂S0 or U⊥γ∩S0=∅, where S0=S\{(x0,y0)}, and (x0,y0) is a point
that is invariant for both U and U⊥. When V is translation we have that V⊥
can be seen as a transversal,
when V is an elliptic movement, then V⊥ is a line through [math], when V is scaling
then V⊥ is scaling.
Note that the invariance principle does not include the movements ⊥ lorentz movements.
However we can define U⊥→V⊥ using Radon-Nikodym’s theorem.
Note that L(Uγ,ξ)=0 iff L(γ,tUξ)=0. If ξ=U⊥γ
we see that tU=(U⊥)−1 implies γ∈K (the light cone).
Starting with a normal tube, where L is an analytic line (Δ), that is assumed to intersect
the first surfaces transversally, we apply a movement U→V, with the property that γ∈Σ
implies Vγ⊂Σ, where Σ={F(γ)=const}. We consider a representation
F∼G, that is regular and with equivalent first surfaces. We have that ([17])
the bases γ can be selected as algebraic for G, given that G has first surfaces of type (A).
Thus, we can regard F(V⊥γ) as an associated function to F(γ) (and F(Uγ)).
Assume, V an euclidean movement, that preserves first surfaces to f and evF the corresponding associated function,
then we have that evF has type (A), if f has type (A).
More precisely given L={γ1=γ2} (formed on Δ) analytic, we can define
the boundary Γ, as first surfaces that intersect L transversally. We can continue Γ
with first surfaces Σ∋γ→Vγ∈Σ. Given the compatibility
conditions, we can further continue the boundary by replacing L with V⊥ and repeat the
argument.
A simple very regular boundary is, FT holomorphic in T and dTdFT holomorphic in T,
where T∈/Σ and Σ are isolated points close to the boundary. Regular approximations
are formed as V1∪V2, where V1={FT\mboxnotconst} and
V2={dTdFT\mboxnotconst}.
Note that given f holomorphic with first surfaces {Sj} and S0={f−α0}
and let E=limjSj, with E∩S0=∅, this implies S0⊂E.
The type for the class of first surfaces depends on the representation of the symbol. For instance
F(γ)=∫Adγ is not dependent of Vγ, where V is translation. When F(γ)=G(xy),
where G is assumed regular, the representation is not dependent of Vγ, when V denotes scaling. Finally
F(γ)=F(∣γ∣) is not dependent of Vγ, where V is rotation and when the
singularities are given by the condition log∣f∣∈L1
they are not dependent of rotation of the symbol.
Boundary condition 1**.**
We assume all singularities are situated at first surfaces for f(ζ). We assume Δ corresponds
to a set Σ, where γ1=γ2. The condition log∣f∣∈L1 implies algebraic singularities.
When the boundary is represented in DL1′, through B(γ)=∫γdμ, where
dμ is assumed very regular, if we let F(γ1)=B1(γ1), we assume as involution
condition dμ1/dμ2=ev, where v∈L1 and v=0 over Σ. Further, we assume
dμ1=0 iff dμ2=0, which when dμj=Xjdxj+Yjdyj, j=1,2, corresponds to
Lie’s point continuation.
9.2 Radon-Nikodym’s theorem
Starting with the lineality we can define the boundary as follows. Assume Δ⊥ are
orthogonals (tangents to Γ) to Δ, we can describe Γ using
eφγ regular relative Δ⊥.
The Radon-Nikodym’s model is, given that I(xy)→0 implies A1(xy)→0,
we have A1(xy)=I(αxy) for some α∈L1.
Note that as A(0,0)=(0,0), we must consider A1(00)=00, (compare L’Hopital).
Assume F1(η(x)) where η(x)=y(x)/x, we then have that
if the limits are on the form F0/0, we must calculate F1(dxdy),
that is we assume that we have non degenerate points and xdxdη=0.
Consider (I1)⊂(I0)⊂(I2)⊥ and γ1→γ1→γ2⊥
that is <γ2,γ2⊥>∼0 (or ∼1), if γ2 polynomial,
we do not necessarily have γ2⊥ polynomial, but it can always be represented as
an annihilator (or (1−γ2⊥)). The moment problem means,
given ∫gdμ=0 with g∈(I1) analytic, that the solution if it exists
is in (I2), for instance dμ=P(D)dv, with dv reduced implies dμ∈E′.
If W is open in V we have that H(V) is dense in H(W), then W has Runge’s property in
V.
Given Runge’s property we can select
(I0) in C0, that is dμ∈C0′, a Radon measure. Oka’s property, in this context
existence of a global base,
is dependent on the domain.
Consider the problem of localisation: assume that V a geometric set and f(ζ)
a symbol over Ω and V not a subset of Ω. Further that we have F(γ)(ζ)=f(ζ)
over Ω. We can construct γ1 over Ω,
such that there exist γ→γ1 continuous (continuation), that is
F(γ)→γ→γ1→V continuous. Assume for instance
that γ1⊥→V continuous (closed) and locally 1-1,
such that γ⊥=rT′γ1⊥ surjective, existence of γ1⊥
defines γ1 (as an annihilator), why γ1∈(IHe)⊥ implies
γ1∈C0, using the moment problem.
The boundary is given by first surfaces {γF(γ)(ζ)=const},
dependent on the involution condition and by {ζF(γ)(ζ)=const}.
When γ is algebraic, we can assume a continuous mapping between these sets.
Let \big{[}F,E_{\delta}\big{]}(\gamma_{2})=const, as δ→0
and logEδ∈L1. Then F corresponds to a solution to a (partially) hypoelliptic
operator and we see that \mboxkerEδ is the kernel to Jγ1.
We thus assume {}^{t}J_{\delta}F(\gamma_{1})=F(J_{\delta}\gamma_{1})=\big{[}F,E_{\delta}\big{]}(\gamma_{2}). Assume F such that
\mboxkerF={0} which implies \mboxkerF⊂\mboxkertJδF.
Further, Eδ→1, as δ→0.
Assume first surfaces to F(γ1)
corresponds to a desingularization, then we have \tilde{S}_{j}=\{\zeta\quad\big{[}F,E_{\delta}\big{]}(\gamma_{2})=const\}
assuming tJδ:const→const.
The condition for the normal n, dt=σdn can be compared with Radon-Nikodym’s theorem.
We assume in this case σ∈L1 over an unbounded set. When σ is independent
of some variable, that is we have a planar obstacle, the condition is not satisfied.
When σ have bounded sublevel-surfaces, it can be given by a regular function.
9.3 Distance functions
Assume dT(γ)=0 implies rT′γ∈Δ and that Δ′ defined through the symmetry
condition F(rT′x,y)=F(x,rT′y), that is we assume Δ⊂Δ′. We define
dT′(γ)=0 implies rT′γ∈Δ′. Define Δ′′ through F(rT′x,y)=F(−y,rT′x),
that is invariance for harmonic conjugation. We define the corresponding pseudo distance d′′.
Finally, we define d0 as a pseudo distance to K={x=y}. Thus (rT′x,y)→(x,rT′y),
that is reflection through K can be seen as d0=const. Further, (rT′x,y)→(−y,rT′x)
can be seen as d′′=const, (−y,rT′x)→(−rT′x,y) through d0=const. The composition,
that is d′′d0=const contains (rT′x,y)→(−rT′x,y).
Note if d1d2=const and d1,d2 distances, we have that d1,d2>0 and
d1d2=0 implies that d1=0 or d2=0, thus A∼B (congruence), that is
d1 denotes the distance to A and d2 denotes the distance to B we have that
z=A or z=B. In particular if A=0 and B=∞, we have that
d2d1=0, for d21(z)=d2(z1).
The example d1d2=const with d1→0 as z→Γ under
the condition d2(z1)=1/d2(z) implies 1/d2(z)→0 and if
d2 reduced, we have z1→∞, that is z→0.
We are assuming no essential singularities in the ∞, why if 1/dΓ→0,
as z→∞, it is a boundary point but not a singularity.
Note that the condition logf∈L1, means that for the ideals defined by dj2
polynomials, such that dj→dj+1 compact, the singularities in the zero space
to limdj2, can be algebraic.
Assume V={v1=const}, we then have that V is bounded if
∣ξ∣σ≤Cv1 when
∣ξ∣→∞, that is if v algebraic in ∞ we have that
V is regular and bounded in ∞. If V′={v=const} and v
downward bounded in ∞ and in the same way if v1 is algebraic in
∞ we have that V′ is regular and bounded.
Assume F(γ)→γ1→γ2→ζ,
where γ1 is hyperbolic and γ2 is partially hypoelliptic. The problem is to
determine if γ1 and γ2 can be constructed starting from the same lineality Δ.
An important difference between hyperbolic and partially hypoelliptic symbols, is that γ1N∈(I1)
iff γ1∈(I1)(Δ) and γ2N∈(I2) does not imply that γ2∈(I2).
Analogously, we have that dγ1∈(I) implies γ1∈(I)(Δ) and dγ2∈(I)
is implied by γ2∈(I), but not conversely, that is for partially hypoelliptic operators,
we have Δ(j)↓{0} and for hypoelliptic operators, we have that Δ(j)=Δ.
The proof of this is based on the condition that Δ⊂, a domain of holomophy.
Assume (I1)⊂(IHe)⊥ is defined by distances, d2⊥/d1→0,
for ζ∈Σ and d1=infζ∣f−c∣, that is distance to the first surface
f(ζ)=F(γ)(ζ). Then if f is an entire function, we have that f→c, as d1→0.
Note that as γ is a pseudo differential operator, we can have that {γ<λ}
is not relative compact. Further, if d2/d2⊥→0, then d2/d1→0
(one-sided orthogonality).
Note that H(Uγ)≡0 defines a regular domain, if H has an analytic kernel, that is
H(Uγ)=∫Uγdμ=0, for some dμ defined by the boundary. Isolated singularities
implies that U is monotropical with an analytic H.
Assume that all singularities can be approximated by
U⊥, we then have that given a fixed U, we can assume Uγ1,Vγ2 algebraic.
If for F∈DL1′, F(γ1→γ2) is analytic over (I1)→(I2), we assume
merely continuity for F over U⊥γ1. Given γ1,γ2 a polynomial,
we can chose F analytic over γ1→γ2.
9.4 Localization
If the boundary is given locally by one single function, we can represent this function as the
solution to a differential operator (boundary operator).
Assume f analytic on a domain Ω, assume γ1∈(IHyp)(Ω) and
that we have existence of F1∈H′(Ω) such that F1(γ1)=γ2∈(IPhe).
Given that we have existence of F2 analytic over γ2,
such that \big{[}F_{2},F_{1}\big{]} analytic over γ1 we have a lifting principle
over γ1→γ2. The base is reversible, if \big{[}F_{1},F_{2}\big{]}
analytic over γ2.
For hyperbolic spaces we have that every pair of points can be linked through a chain of
analytic discs (the transversal analytic). Assume Sj a first surface to a hyperbolic
base and S~j the continuation to the partially hypoelliptic base
as simply connected domains. If we assume the continuation algebraic, with
logf~∈L1, we still have singularities of finite order,
but this does not imply that the transversal is analytic (or locally algebraic).
Assume that the continuation is given by d1d2, such that S1→S2
through reflection with respect to a reflection axes in π. Transversals can be seen as
⊥π. On the hyperboloid, we can always represent proper movements as reflection
∼ a normal model. Movement can be continued to euclidean metric, also the reflection axes,
but orthogonals (corresponding to the transversal) are not necessarily analytic.
Note that in the problem of localisation, the condition of surjectivity is not necessary.
It is sufficient with existence of γ, such that f(ζ)→γ→V continuous.
Assume ∀γ∈(J) we have existence of R hypoelliptic with Rγ2=γ.
Assume P∗=R in DL2′.
When E is very regular, we have that Eγ=γ2 hypoelliptic and E∼δ0−η
implies γ=γ2+η∗γ gives an approximative solution.
In this article, the mixed problem is dealt with as F(γ1→γ2)(ζ)=f(ζ) and in the converse direction over γ2→γ1, the mixed
problem is already extensively dealt with (for instance [8],[9]).
Assume f1∼f+δ. This equivalence can be used in connection with Cousin’s model
of monotropy. For isolated singularities we have f1(ξ)=f(ξ)+δ=f(ξ+ϵ).
We do no have in this case a normal covering in the sense of Weyl ([25]), but
using a reduced complement, if the singular points are ∈/\mboxsuppμ,
we can assume f⊥μ iff f−δ⊥μ. In connection with double transform,
P(D)δ→P(ξ)→P(ξ∗),
when f(ζ)+δ(ζ)=F(rT′γ)(ζ), where F is linear in γ.
Given γ analytic,
we can locally write F∼1/Q for a polynomial Q, in this case F(γ) is constant.
Given ∫gdμ=0 with g algebraic, we have that the intersection is of measure zero.
When g is not algebraic, we are discussing one-sidedness. F(g+)=G(g−)
where the regularity is preserved.
9.5 Continuation of the boundary
Assume the boundary Γ extended with mirrors (congruent to tangents) to
Γ~. Starting from a boundary point in Γ selected as origo,
the problem is to reach the others through a chain of broken rays. If also the chain
is regarded as Γ~ then we reach in this manner a subset of the boundary of
positive measure (we assume the symbol f=0 over the chain). Assume that dμ a boundary measure
([6]) and denote with dμ~ the measure corresponding to the extended
boundary. Thus Γ~→{∣z∣=1}
Consider now A(x,y)=A(x(1,xy)). If (1,xy)∈Ω, where Ω
is the domain for analyticity for A, we have that A is analytic on 1+∣xy∣2≤1,
In particular, if f is analytic on (1,xy) with ∣xy∣<1 and
on (x,0) where ∣x∣<1, we have that f is analytic on ∣x∣2+∣y∣2≤1.
The symmetry condition F(rT′x,y)=F(x,rT′y) means that the zero set is symmetric in
(x,y). If F(x,y)=0 we have that F=0 in rT′x, for y fixed, that is on a cone
relative rT′ (relative homogeneity).
The condition yT/xT=y/x can be written F(rT′x,rT′y)=F(x,y).
Assume P hyperbolic and Q partially hypoelliptic with Δ(P)=Δ(Q),
consider for a parmetrix E1 to P, τPv=P, that is vE1=E1 over Δ.
If E2 is parametrix to Q and if we consider the parametrices as Fredholm operators,
with the difference that \mboxkerE2 can be reduced to a trivial space through iteration.
Assume Δ⊥ is given by Sj, continued to S~j through
M(eψdγ)→eϕM(dγ) continuous,
where ϕ∈L1. If we have ϕ>0, we have trivial first surfaces,
corresponding a reduced operator.
We are assuming S~j can be continuously deformed to Sj using ϕ.
If we assume the symmetry condition for ϕ, we can
assume the deformation independent of parabolic movements.
If F(γ) is of type (A), which is the case where γ=γ1, we can chose
F(γ)=P(D)f~0, where f~0 is very regular and the compatibility condition
according to Kiselman ([13]) means that we have existence of Qj⊥P. Assume ϕj corresponds to
γ2j, such that in this case ϕj→0, when j→∞.
Note the difference between the zero space and constant surface, ϕ1+ϕ2=const.
If we describe the first surfaces as V1∪V2 where Vj is connected,
this corresponds to a multiply connected boundary, where every ϕj
is assumed such that the transversal is locally represented as a polynomial
(at least analytic).
Assume μ a reduced measure of bounded variation and μ2=P1…PNμ,
we have in this case not approximations on the form of orbits. In this case, even if we
for monotropic functions do not have have presence of a normal covering in the sense of Weyl,
we do not have problems with orbits, given that we start with a reduced measure in the
representation of the boundary.
Note the moment problem, if we assume α reduced, we then have α(g)=0
implies g=0 on the domain Ω, that is given α∈DL1′ is
Ω a strict carrier to α. Since g≡0 on Ω
or α(Ω)=0, if g is a polynomial and if α reduced, we must Ω is trivial.
Finally, if the condition is ϕ∈L1 and we consider ψ∈H(V) such that
ψ∼mϕ, we do not longer have a normal covering,
but according to the moment problem, we can uniformly approximate C∩L1 with
H(V), over a strict carrier to the measure α. If we only assume the measure
α of bounded variation, but instead we chose g as polynomial, we can assume ’
Ω has α− measure zero.
Given a measure of bounded variation and positive definite dμ, such that
dμ~=dμ+dμ0, where dμ0 is assumed with point support and
dμ~ holomorphic, we have a continuation according to Cousin ([3], compare also [6]).
When dμ~ locally reduced, we have ∫γT−γ0dμ~=0
implies γT=γ0.
When dμ~ is not reduced, there is the centre case among the possible approximations,
that is orbits around a singular point.
Given g a regular approximation and
dμ~ with support on first surface (the boundary), assume ∫gdμ~=0
under the approximations. Given dμ~ reduced, we can assume g=0 outside a compact set.
It is clear that L (transversals) are included in the support for g, in this manner we can regard L as a strict carrier for limits.
The proposition is that given the transversal as a strict carrier for limits, the transversal can
be represented through polynomial locally.
The boundary is assumed very regular in the sense Parreau ([19]). We assume all
singularities on first surfaces and that all first surfaces can be reached.
In the context of the moment problem, we can allow monotropical functions,
that is g can be continued to continuous functions.
Assume M=dμ~/dz and dzdG=g, we then have if g regular that dG
is a closed form.
Assume Σ={f(ζ)=const} and JU=VJ according to the invariance principle
and S={F(γ1)=const} and S~={F(γ1→γ2)=const}.
If φ is a continuous function in a neighbourhood of (x0,y0) and σ
a characteristic surface through this point, we can then write σ⊂{φ(x,y)>0}\(0,0)
(pseudo convexity) and σ={xn=P(x1,…,xn−1)} (strict pseudo convexity ([18])).
We define Uγ1=Vγ2 in a neighbourhood of Δ={U=V=I} and assume
F(Uγ1)→const. For all singularities that can be reached in this manner,
given U is a fixed movement, we can chose γ1→γ2 as analytic
(polynomial) .
Note that, if Δ is a plane xj=0, we have that ev is constant in some direction,
why the function is not in L1 on an unbounded domain.
Given 0=∫Vgdμ we have that g≡0 on V or μ(V)=0 (measure zero).
Given g polynomial (exponential of a polynomial) we have from a result by Hurwitz ([3])
that the measure for all singularities is zero. In the transposed case 0=∫Mdg
implies M=0 or g(V)=0. If for instance M is locally 1-1, we have that x=x0.
10 The moment problem
Note the moment problem, assume E0 a set in C, the problem can be solved if we existence of α(x) of bounded variation, such that ∫g(x)dα(x)=0
for g∈E0, we have ∫g(x)dα(x)=0 for g∈C ([4]). Note that
when the orthogonal (transversal) is algebraic, this corresponds to a measure zero complement .
Concerning mixed problems, assume (Au,v)=(u,A∗v), such that A∗v=0, that is
v⊥Au=f. Given that Bu=v, we have thus A⊥B or A∗B⊥I.
Note R(B)=D(A)⊥ and R(A)=D(B)⊥. If
R(A)⊥=R(B) we have that B has closed range, even when A does not.
If B is algebraic in Rn, we have that given v, we have existence of u such that
Bu=v. The domain for ⊥ is then u, such that u∈D(A)∩D(B) that is closed
when D(A) is closed. Note if A is a polynomial, there are complex polynomials B∗,
such that the symbol to B∗A≡0 ([13]). If we consider B∗ as annihilator, (B∗Au,u)=0
for all u∈D(A). When A is considered in X′, we have B∗A=0, that is B∗ is an
annihilator for A.
Compare with the moment problem, where a sufficient condition, given finite order singularities, for existence of B∗ is an analytic
representation of A (Parseval).
Consider now A hyperbolic and BN hypoelliptic, it is sufficient to consider u with ANu=fN and BNv=0 for v⊥f.
Note that if EN is a parametrix to BN, it has (modulo C∞) a trivial kernel, that is
if v′=ENv, fN⊥v, we have v′=0.
The mixed model**.**
Assume γ→γδ is a continuation of γ and Fδ is constructed,
so that Fδ(γδ)=f and respects f⊥v, where v is continuous. Assume tFδ has a trivial
kernel, then the continuation gives a global mixed model.
Note that δ0−C∞ maps D′→D′F,
that is if the boundary is defined modulo regularizing action instead of modulo H,
we do not longer have that rT is injective in H, however it is injective in L1.
We will use the moment problem (and when possible the transmission problem ([14])) to solve the mixed problem. In the two mirror model
we assume that a hyperbolic operator A, is reflected through the boundary into an operator A∗
(geometrical optics) and in the same manner for B partially hypoelliptic. Existence of a continuous
mapping between the respective boundary points, implies an abstract transmission property.
Note that only one of the systems has to be invertible.
Assume the condition Bγ1=0 on Σi corresponds to Δ(f) (lineality), then there is a B′ such that
Bγ1=0 iff B′γ2=0 on Σi. Thus, if γ2 is seen as a
continuation of γ1 according to F(γ1→γ2)
with γ1⊥γ2, we have a “global model”. We have <F(γ1),v>=0 and
tF(v)⊥γ1 and tF(v)=0 implies v⊥F(γ1),
where F is a parametrix (localization) to γ1→γ2. Further, <F(γ2),v>=0
and v∈\mboxkertF={0}, which implies v=0. Assume Jδ:γ1→γ2,
when δ→0 and Jδγ1⊥γ1, further that (tJδF)→E
with \mboxkerE={0}. Define Fδ∼(tJδF) with
<γ1,tFδv>→0, as δ→0. According to the above,
this implies v=0, which implies Fδ=id. Thus, if Fδ(γ1)=f with Fδ=id,
then this implies that f hyperbolic and when Fδ(γ2)=f with Fδ=id, then this
implies that f hypoelliptic.
Generally, for a radical geometric ideal, it is sufficient to give the boundary condition on derivatives to the symbol.
Consider otherwise the problem for M(f) (arithmetic mean).
The boundary condition, when it is radical, can be given for the derivative, but does not necessarily define
the domain. The radical boundary condition, does not imply a radical ideal.
Consider Jδ:γ1→γ2, such that limδ→0Jδγ1→
a hypoelliptic symbol. Write Jδγ1=γδ, we then have F(J_{\delta}\gamma_{1})=\big{[}F,E_{\delta}\big{]}(\gamma_{2}), where Eδ∼evδ, where vδ=0
on invariant sets. On the other hand, Fγ2=1, as vδ=0 implies \mboxkerF={0}.
Assume F(γ)→γ→ζ. When Uγ is analytic, we have U~ζ
continuous. Note that {ζUγ1=γ1}={ζUγ12=γ12}
and {ζVγ22=γ22}⊂{ζVγ2=γ2}. As JδUγ12=VJδγ12=Vη2
where η2=Jδγ12 and η2∈(IPhe).
Consider the continuation Sj→S~j simply connected.
Given Oka’s condition for S~j and the continuation of the symbol, the transversal can be defined
as analytic (algebraic) even for S~j. Concerning the set {f<λ}=V,
if we have Sj⊂⊂V and Sj is a bounded set, we do not necessarily have the same
for S~j. The proposition for the continuation implies a downward bounded symbol.
According to Weyl ([25]), we have for a normal covering, that closed curves corresponds to
closed curves. According to ([20]) (Ch. XXVII), we have modulo monotropy, that closed curves
correspond to open curves with points in common with its closed correspondent.
We can use the moment problem, given ∫(Γ)gdα=0 for a reduced
measure of bounded variation,
for 0=g∈E0 implies the same relation for g∈C. Thus, in the plane we can use a
reduced measure (modulo removable sets) to solve the problem.
Assume (I)=(\mboxkerh) and dh(f)=g(z)dz, where g∼mg1 analytic. Assume
g−g1 algebraic and g1 regular over closed contours. We can assume one-sided regularity for
g. For instance, f(1/x)g(x)
where f is bounded close to the ∞ and g is bounded close to [math].
Assume a two-sided limit and F+(g+)−F−(g−)→0 at the boundary. Assume
g−∼g+∗ and F−(g−)∼F+∗(g+), we then have F+−F+∗(g+)→0
and through Radon-Nikodym’s theorem, we have F+(g+)=F−(evg−), where v∈L1.
The Schrödinger operators ([22]) give a global model, that is not normal.
If we select dμ very regular, that is hypoelliptic in L2,
the representation of the symbol is locally 1-1, why we have two-sided limits.
Compare with ∫g(dμ−dμ0)=0, where dμ0 has
point support. Then dμ=vdz and <g,dμ>=<g,v> and v=v1+v0, we can assume
v0∼δ/g. Note that V⊥γ→x0 does not imply Vγ→x0.
Consider V⊥→x∗ continuous and V→x, further that x0 is a
joint point. For instance, if f(x∗)→1, we have simultaneously
f(x)→δ. We can then have x∗→x0 without simultaneously x→x0
Concerning pseudo vectors, consider a neighbourhood of a point on Hm. An infinitesimal displacement
can be performed as parabolic, elliptic or hyperbolic. The normal is considered relative an axes
for invariance, that is we consider the normal as independent of the neighbourhood. Assume for x,y real,
η(x)=y(x)/x=eϕ(x). We have then three possibilities, ϕ=0 parabolic, ϕ<0 hyperbolic and ϕ>0 elliptic.
The three possibilities induce three possible orientations for the normal. In particular in the parabolic case,
if the normal is dependent on scaling parameter h, as h→0 or h→∞, we have
a “ scaling orientation” for the normal. In the case where the transversal is a strict carrier or a carrier,
the limit is not dependent of choice of neighbourhood.
Form the normal in a point ζ0 at the boundary Γ={ζF(γ)(ζ)=const.}
and consider γ(ζj+h)−γ(ζj−h), where h is a scalar. Obviously, if
γ is symmetric with respect to ζ0 over the segment, we have that γ is absolute
continuous, as h→0. In this case the definition of the normal, does not depend on h.
Consider G(h)=∫N(ζ)γ′(ζ)dζ,
where for instance ζ=(ζ1,…,ζj+h,…,ζn). When N is polynomial
over the segment Ih, we have when γ is absolute continuous and G(h)≡0, that γ=const.
over Ih. Further, N⊥dγ, independent of h→0. Consider now N∈DL1′,
summable with respect to dF, of bounded variation, we then have that G is absolute continuous with respect to dF,
that is F(Ih)→0, as h→0, implies G(h)→0. When G≡0,
we have that N⊥dF. Thus, when N∈L1(dF), we have if G absolute continuous with respect to dF,
that N⊥dF, as h→0. When N is dependent on h, we may have G↛0, as h→0.
Further, when N has a strict carrier, then N is independent of h for large h. This “orientation”
of N is represented using regularity conditions.
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