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arXiv · 2604.15988

Testing Scalar Field Self-Dualities in d=2 using a Variational Method

Paul Romatschke·Ulrike Romatschke
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Abstract

Recently, self-dualities based on saddle-point expansions have been proposed as a means to obtain qualitative non-perturbative information in scalar field theories. In this work, we test this proposition quantitatively by studying the phase transition for critical scalar $\phi^4$ field theory in 1+1 dimensions using a variational method. We find that saddle-point methods obtain quantitative agreement for the free energy, but differ on the order of 25 percent for the peak location of the correlation length.

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Paul Romatschke, Ulrike Romatschke. 2026-04-17. Testing Scalar Field Self-Dualities in d=2 using a Variational Method. https://arxiv.org/abs/2604.15988

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