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arXiv · 2607.28975

Chiral symmetry and curvature bounds in de Sitter spacetime

L. G. Barbosa
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Abstract

We study chiral symmetry breaking in the Nambu-Jona-Lasinio model on a de Sitter background, treating it as a non-renormalizable effective field theory with a physical ultraviolet cutoff. Using exponential proper-time regularization, we obtain an exact solution for the constituent fermion mass in the strong-curvature regime via the Lambert $W$ function. The consistency condition for real-valued solutions leads to an upper bound on the cosmological constant, indicating a limitation of the mean-field description rather than a fundamental physical constraint on the spacetime geometry.

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L. G. Barbosa. 2026-07-31. Chiral symmetry and curvature bounds in de Sitter spacetime. https://doi.org/10.1142/s0217732326502202

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