Hiding the cosmological constant

TL;DR

This paper proposes a model where quantum fluctuations and initial conditions lead to a spacetime foam that hides a large cosmological constant at observable scales, challenging standard effective field theory expectations.

Contribution

It introduces a framework where initial inhomogeneities and quantum effects result in a spacetime foam that conceals the cosmological constant at large scales.

Findings

Initial data exhibit large local curvatures that average to zero macroscopically.

Quantum fluctuations may preserve inhomogeneities over time.

The model aligns with Wheeler's spacetime foam concept, hiding the cosmological constant.

Abstract

Perhaps standard effective field theory arguments are right, and vacuum fluctuations really do generate a huge cosmological constant. I show that if one does not assume homogeneity and an arrow of time at the Planck scale, a very large class of general relativistic initial data exhibit expansions, shears, and curvatures that are enormous at small scales, but quickly average to zero macroscopically. Subsequent evolution is more complex, but I argue that quantum fluctuations may preserve these properties. The resulting picture is a version of Wheeler's `spacetime foam,' in which the cosmological constant produces high curvature at the Planck scale but is nearly invisible at observable scales.