Quantum entanglement in de Sitter space from Stringy Axion: An analysis using $\alpha$ vacua

Understand

In this work, we study the phenomena of quantum entanglement by computing de Sitter entanglement entropy from von Neumann measure.

• For this purpose we consider a bipartite quantum field theoretic setup in presence of axion originating from ${\bf Type~ II~B}$ string theory.
• We consider the initial vacuum to be CPT invariant non-adiabatic $\alpha$ vacua state under ${\bf SO(1,4)}$ ismometry, which is characterized by a real one-parameter family.
• To implement this technique we use a ${\bf S^2}$ which divide the de Sitter into two exterior and interior sub-regions.