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arXiv · 2412.04971

Tripling Fluctuations and Peaked Sound Speed in Fermionic Matter

Hiroyuki Tajima·Kei Iida·Toru Kojo·Haozhao Liang
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Abstract

A crossover involving three-fermion clusters is relevant to the hadron-quark crossover, which, if occurring in a neutron star, could naturally reproduce the dense-matter equation of state recently deduced from simultaneous observations of neutron-star masses and radii. To understand the crossover mechanism, we examine the role of tripling fluctuations induced by the formation of three-fermion clusters. The phase-shift representation of fluctuations manifests an interplay of bound and scattering states, leading to non-monotonic momentum distributions of baryon-like clusters and peaked sound speed at finite densities. We demonstrate them by applying our approach to a nonrelativistic system of one-dimensional three-color fermions analogous to the hadron-quark matter.

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Hiroyuki Tajima, Kei Iida, Toru Kojo, Haozhao Liang. 2024-12-06. Tripling Fluctuations and Peaked Sound Speed in Fermionic Matter. https://doi.org/10.1103/4ywp-752m

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