Mathematical physics sits at the fascinating intersection where abstract equations meet the fundamental laws of our universe. This field uses rigorous mathematical tools to model everything from the behavior of subatomic particles to the curvature of spacetime, turning complex theories into testable predictions. It is the language through which physicists describe reality, bridging the gap between pure mathematics and physical observation.

On Gist.Science, we process every new preprint published in this category on arXiv to make these dense studies accessible to everyone. Whether you are a specialist or a curious reader, you will find both plain-language overviews and detailed technical summaries for each paper. Below are the latest mathematical physics papers from arXiv, curated to help you explore the cutting edge of theoretical science.

🔢 mathematics

Entropy Maximization and Weak Gibbsianity of Quasi-Free Fermionic States

This paper resolves the long-standing questions of uniqueness and weak Gibbsianity for gauge-invariant quasi-free fermionic states by proving that, under specific conditions on their momentum-space two-point functions, these states uniquely maximize entropy among translation-invariant states and are indeed weak Gibbs states, with both properties derived directly from thermodynamic formalism.

Vojkan Jakšić, Claude-Alain Pillet, Anna Szczepanek2026-03-17
⚛️ general relativity

Further Results on Null and Force-free Electromagnetic Fields

This paper establishes a general existence theorem for null Force-Free Electrodynamics solutions by proving that any null geodesic congruence admits a transverse basis rotation satisfying the equipartition condition and that shear-free congruences guarantee the existence of field sheet foliations, thereby providing a coordinate-independent geometric criterion for such solutions illustrated through explicit examples in various spacetimes.

Govind Menon, Rakshak Adhikari2026-03-17
🔢 mathematics

Nonholonomic constraints at finite temperature

This paper demonstrates that naively applying stochastic and dissipative terms to nonholonomic systems like the Chaplygin sleigh violates the second law of thermodynamics, but this paradox is resolved by modeling the constraint as a viscous limit that necessitates accompanying stochastic forces, thereby restoring thermodynamic consistency and establishing fundamental limits on the physical realizability of idealized nonholonomic constraints.

Eduardo A. Jagla, Anthony M. Bloch, Alberto G. Rojo2026-03-17
🔢 mathematics

Exact characterizations for quantum conditional mutual information and some other entropies

This paper provides sharp, exact characterizations of quantum conditional mutual information and other entropies by transforming their definitions into rapidly converging sums of explicitly constructed terms that inherently demonstrate desired properties like positivity and convexity, thereby offering precise equalities for both small and large values without relying on approximations.

Zhou Gang2026-03-17
🔢 mathematics

Towards a Gagliardo-Type Theory of Fractional Sobolev Spaces on Arbitrary Time Scales

This paper introduces a Gagliardo-type framework for fractional Sobolev spaces on arbitrary time scales using the Lebesgue Δ\Delta-measure and off-diagonal interaction energies, establishing their Banach and Hilbert space properties, proving Poincaré-type inequalities that reflect the underlying geometry, and unifying continuous, discrete, and hybrid settings.

Hafida Abbas, Abdelhalim Azzouz2026-03-17
🔢 mathematics

The Zak phase in topologically insulating chains: invariants and quaternionic constraints

This paper investigates the topological content of the Zak phase in one-dimensional topological insulators across all Altland-Zirnbauer-Cartan symmetry classes, demonstrating how to construct a Z2\mathbb{Z}_2-valued invariant from the Zak phase while revealing that quaternionic structures imposed by specific anti-unitary symmetries force this invariant to vanish.

Federico Manzoni, Domenico Monaco, Gabriele Peluso2026-03-17