Nonvanishing Cosmological Constant of Flat Universe in Brane-World Scenario

TL;DR

This paper investigates how finite temperature effects in the Randall-Sundrum brane-world scenario lead to a nonzero cosmological constant at flat spacetime, aligning with observed small values.

Contribution

It demonstrates that finite temperature induces a small, nonvanishing cosmological constant in a flat universe within the brane-world framework, extending previous zero-temperature conformal invariance results.

Findings

At 4d effective level, temperature-dependent cosmological constant is derived.

At 3 K, the cosmological constant is approximately (0.0004 eV)^4.

The predicted cosmological constant aligns with recent experimental bounds.

Abstract

The finite temperature effect is examined in Randall-Sundrum brane-world scenario with inclusion of the matter fields on the brane. At zero temperature it is found that the theory on the brane is conformally invariant, which guarantees $AdS$/CFT. At 4d effective action we derived a temperature-dependent nonvanishing cosmological constant at the flat spacetime limit of brane worldvolume. At the cosmological temperature $3 {\bf K}$ the cosmological constant is roughly $(0.0004 eV)^4$ which is within the upper bound of the recent experimental value $(0.01 eV)^4$