Strings as a Model for Parent and Baby Universes: Total Splitting Rates

TL;DR

This paper models the emission of microscopic strings as a branching process of baby universes off a parent universe, showing that quantum coherence loss is unsuppressed regardless of the universe's size.

Contribution

It introduces a string-based model for universe branching and demonstrates that total emission rates are not suppressed by the universe's size, implying significant coherence loss.

Findings

Total emission rate is not suppressed by the size of the macroscopic string.

Quantum coherence loss in the parent universe is unsuppressed.

Emission process can be viewed as a branching of baby universes.

Abstract

Emission of hard microscopic string (graviton) by an excited macroscopic string may be viewed as a model of branching of a $(1+1)$-dimensional baby universe off large parent one. We show that, apart from a trivial factor, the total emission rate is not suppressed by the size of the macroscopic string. This implies unsuppressed loss of quantum coherence in $(1+1)$-dimensional parent universe.