de Sitter p-Universes

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HEP-Theory Group, Milano-Bicocca, talks

Tarek Anous

U2 - 5017

Title: de Sitter p-Universes

Abstract:  We analyze a simple extension of the Schwinger model, which we refer to as the $p$-Schwinger model,  on a fixed de Sitter a background. In this theory, the charged massless fermions carry non-unit integer charge, $p$. In Minkowski space, the $p$-Schwinger model has discrete global symmetries that are spontaneously broken, yielding $p$ degenerate ground states. These can be organized into superselection sectors, p-Universes, that admit no mixing even at finite temperature. We demonstrate that these effects persist upon placing the p-Schwinger model on a global de Sitter background, establishing that discrete global symmetries can be spontaneously broken for quantum field theories in de Sitter space. In particular, the theory is endowed with p distinct, but locally indistinguishable, de Sitter invariant states, the de Sitter vacua, which are Hadamard, (unlike the alpha states).

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