Loop-Effects in Pseudo-Supersymmetry

TL;DR

This paper investigates how supersymmetry breaking effects propagate in brane-world models with pseudo-supersymmetry, revealing that scalar masses and Casimir energies depend on the compactification scale and exhibit specific logarithmic behaviors.

Contribution

It provides explicit two-loop and three-loop calculations of scalar masses and Casimir energy in a 5D pseudo-supersymmetric brane model, highlighting the effects of brane separation.

Findings

Scalar masses are positive and proportional to the inverse square of the compactification radius.

Casimir energy between branes is repulsive and scales with the fourth power of the inverse radius.

Mass and energy calculations include logarithmic corrections dependent on the ultraviolet cutoff.

Abstract

We analyze the transmission of supersymmetry breaking in brane-world models of pseudo-supersymmetry. In these models two branes preserve different halves of the bulk supersymmetry. Thus supersymmetry is broken although each sector of the model is supersymmetric when considered separately. The world-volume theory on one brane feels the breakdown of supersymmetry only through two-loop interactions involving a coupling to fields from the other brane. In a 5D toy model with bulk vectors, we compute the diagrams that contribute to scalar masses on one brane and find that the masses are proportional to the compactification scale up to logarithmic corrections, m^2 ~ (2 pi R)^{-2}(ln(2 pi R ms)-1.1), where ms is an ultraviolet cutoff. Thus, for large compactification radii, where this result is valid, the brane scalars acquire a positive mass squared. We also compute the three-loop diagrams relevant to the Casimir energy between the two branes and find E ~ (2 pi R)^{-4}((ln(2 pi R ms)-1.7)^2+0.2). For large radii, this yields a repulsive Casimir force.