Hep-Th, or high-energy theoretical physics, explores the fundamental building blocks of our universe and the forces that govern them. Researchers in this field use complex mathematics to understand everything from subatomic particles to the behavior of black holes, often pushing the boundaries of what we know about space and time.

At Gist.Science, we monitor the arXiv repository to ensure you stay ahead of the curve in this rapidly evolving discipline. For every new preprint uploaded to arXiv under this category, our team generates both accessible plain-language overviews and detailed technical summaries, making cutting-edge research understandable regardless of your background.

Below are the latest papers in high-energy theoretical physics, curated to help you navigate the most significant recent discoveries.

Generalised Symmetries and Swampland-Type Constraints from Charge Quantisation via Rational Homotopy Theory

This paper refines the postulate that charge quantization is governed by a homotopy type A\mathcal{A}, demonstrating that while its homotopy groups classify brane charges, its homology groups classify invertible higher-form symmetries, and ultimately shows that the requirement for A\mathcal{A} to be contractible in quantum gravity imposes Swampland-like constraints, such as ruling out noncompact gauge groups.

Luigi Alfonsi, Hyungrok Kim, William G. A. Luciani2026-04-27⚛️ hep-th

Carrollian quantum states and flat space holography

This paper uses an algebraic approach to study free Carrollian quantum field theories, demonstrating that while massive theories allow for regular vacuum and thermal states, massless theories exhibit more complex behaviors that necessitate a Hilbert space representation consisting of both a standard Fock sector and a nonseparable zero-mode sector, providing new insights into the role of infrared degrees of freedom in flat space holography.

Stefan Fredenhagen, Stefan Prohazka, Robert Tiefenbacher2026-04-27⚛️ hep-th

The Origin of the Dynamical Quantum Non-locality

This paper rigorously establishes that dynamical quantum non-locality originates from the superposition principle by proving that the Wigner propagator reduces to its classical counterpart if and only if the Hamiltonian is at most quadratic, and introduces a measurable signed divergence D(t)\mathcal{D}(t) that unifies the understanding of five distinct quantum phenomena ranging from non-local games to metrological gains.

Cesar E. Pachon, Leonardo A. Pachon2026-04-24🔬 physics.atom-ph

Derivation of a \PT\PT-Symmetric Sine-Gordon Model from a Nonequilibrium Spin-Boson System via Keldysh Functional Integrals

This paper presents a microscopic derivation of a PT\mathcal{PT}-symmetric non-Hermitian sine-Gordon effective theory from a nonequilibrium spin-boson system using Keldysh functional integrals, establishing a precise dictionary between microscopic parameters and effective couplings to demonstrate that the resulting renormalization group flow, exceptional point physics, and bound-state spectrum align with established non-Hermitian sine-Gordon results.

Vinayak M. Kulkarni2026-04-24🔢 math-ph

Non-classicality of Primordial Gravitational Waves in Three-mode Representation Through Quantum Poincare Sphere

This paper generalizes the description of primordial gravitational waves from a two-mode to a three-mode Bogoliubov transformation, revealing that while large squeezing can render the universe classical if only two modes are considered, the full three-mode analysis preserves quantum characteristics via the quantum Poincaré sphere for any non-zero squeezing or non-zero coherent state components.

Anom Trenggana, Freddy P. Zen2026-04-24⚛️ gr-qc