Dark Energy from Strings

TL;DR

This paper derives the small cosmological constant value from a string cosmology model where dark energy results from correlations between string modes, suggesting a string-theoretic origin for dark energy.

Contribution

It introduces a novel string cosmology framework explaining dark energy as a frozen condensate of string modes, connecting string theory with cosmological observations.

Findings

Derivation of the tiny cosmological constant from string theory.

Dark energy modeled as a condensate of string modes.

Correlation between momentum and winding modes explains dark energy.

Abstract

A long-standing problem of theoretical physics is the exceptionally small value of the cosmological constant $\Lambda \sim 10^{-120}$ measured in natural Planckian units. Here we derive this tiny number from a toroidal string cosmology based on closed strings. In this picture the dark energy arises from the correlation between momentum and winding modes that for short distances has an exponential fall-off with increasing values of the momenta. The freeze-out by the expansion of the background universe for these transplanckian modes may be interpreted as a frozen condensate of the closed-string modes in the three non-compactified spatial dimensions.