Hep-Ph explores the fundamental forces that govern how particles interact and behave at the smallest scales imaginable. This field bridges the gap between theoretical predictions and experimental reality, helping scientists understand the building blocks of our universe without getting lost in complex mathematics. Whether investigating the Higgs boson or searching for new physics beyond current models, these studies push the boundaries of human knowledge about matter and energy.

At Gist.Science, we process every new preprint in this category as soon as it appears on arXiv. We strip away the dense jargon to offer both accessible plain-language explanations and detailed technical summaries, ensuring that groundbreaking research is understandable to everyone from students to seasoned experts. Below are the latest papers in this dynamic field, ready for you to explore with clarity and depth.

⚛️ phenomenology

CMB observables and reheat temperature as a window to models of inflation and freeze-in dark matter production

This paper presents a systematic framework that links Cosmic Microwave Background observables and the reheating temperature to discriminate between inflationary models and constrain freeze-in dark matter production, demonstrating how current and future data can test α\alpha-attractor models and establish consistency between early-universe cosmology and particle physics.

Anish Ghoshal, Paweł Kozów, Marek Olechowski, Stefan Pokorski2026-09-10
🔭 astrophysics

Decoding the Imprints of Energy-Momentum Squared Gravity in Neutron Stars with Machine Learning Analysis

This study demonstrates that supervised machine learning classifiers, particularly Random Forest, can achieve over 99% accuracy in distinguishing between General Relativity and Energy-Momentum Squared Gravity models using neutron star observables (mass, radius, tidal deformability, and oscillation frequency), even after applying observational constraints.

Sayantan Ghosh, Premachand Mahapatra, Dipti Deb2026-09-10
⚛️ high-energy theory

Bounds on scattering amplitudes of non-identical scalar particles in 4d

This paper initiates the S-matrix bootstrap study of two-to-two scattering for two distinct scalar particles in four dimensions, revealing that unequal masses introduce an unbounded pseudo-physical cut which qualitatively alters the bounds on observables until the equal-mass limit is reached or additional information is supplied.

Gabriele Ferretti, Denis Karateev, Alessandro Piazza, Marco Serone2026-09-10
⚛️ high-energy theory

Cosmological Collider Signals From a Triangle Loop

This paper presents the first derivation of analytical leading-order cosmological collider signals from massive scalar triangle loops in inflationary bispectra and trispectra by combining directional cutting rules with partial Mellin-Barnes representations, revealing that these complex loop signals are effectively reproduced by corresponding bubble diagrams with a single pinched coupling.

Zhehan Qin, Zhong-Zhi Xianyu2026-09-10
⚛️ high-energy experiments

Bell tests for collider decay processes

This paper proposes a Bell test framework for collider decay processes that, while requiring postselection which introduces a loophole, demonstrates that any local model exploiting this loophole must be nonclassical in the sense of measurement contextuality, thereby allowing the violation of a derived Bell inequality to witness either Bell nonlocality or contextuality.

Danilo M. Fucci, Alexandre C. Orthey Jr., Alan J. Barr, Christopher G. Timpson2026-09-10
⚛️ phenomenology

Nucleon Stron-Interactions Size From Charmonium Photoproduction

By combining recent high-precision near-threshold J/ψJ/\psi photoproduction data from Jefferson Lab with quark-sector results, the study reveals that the nucleon's overall strong-interaction spatial extent, which governs mass generation, is approximately 0.94±0.090.94\pm 0.09 fm and extends beyond its electromagnetic charge and mass distributions.

Xiangdong Ji, Sylvester Joosten, Zein-Eddine Meziani, Dimitra A. Pefkou2026-09-10