Quantum gravity represents the frontier where the very large meets the very small, attempting to unify Einstein's theory of gravity with the strange rules of quantum mechanics. This field explores the fundamental fabric of spacetime, seeking to understand how the universe behaves at its most extreme scales, from the heart of black holes to the moment of the Big Bang. Because these concepts often involve complex mathematics, they can feel distant to non-specialists, yet they hold the key to a complete picture of physical reality.

At Gist.Science, we bridge this gap by processing every new preprint in this category directly from arXiv. Our team provides both plain-language explanations and detailed technical summaries for each paper, ensuring that groundbreaking research is accessible to everyone, from curious students to seasoned researchers. Below are the latest papers in quantum gravity, offering fresh insights into the nature of our cosmos.

Holography and Optimal Transport: Emergent Wasserstein Spacetime in Harmonic Oscillator, SYK and Krylov Complexity

This paper proposes that holographic spacetime emerges as a Wasserstein space through optimal transport of quantum state distributions, demonstrating that the 1-Wasserstein distance between Husimi Q-representations serves as a generalized Krylov complexity to reproduce black hole geometries in harmonic oscillators and SYK models under the manifold hypothesis.

Koji Hashimoto, Norihiro Tanahashi2026-04-21⚛️ hep-th

Thermodynamic behavior of cosmological models with fractional entropy

This paper investigates a cosmological model based on fractional entropy applied to the apparent horizon, demonstrating that the model remains thermodynamically stable during late-time acceleration and that observational data from Cosmic Chronometers, Pantheon+SH0ES, and DESI DR2 BAO favor a fractional parameter close to the General Relativity limit while revealing a distinct modulation of the Hubble constant and matter density as the parameter varies.

Miguel Cruz, Diego da Silva, Simón González, Samuel Lepe, Joel Saavedra, Manuel Gonzalez-Espinoza2026-04-21⚛️ gr-qc

Testing cosmological isotropy with gravitational waves and gamma-ray bursts

This study utilizes the latest LIGO-Virgo-KAGRA gravitational wave data and a comprehensive gamma-ray burst catalog to test the cosmological principle, finding no significant evidence for anisotropy and thus supporting the hypothesis that the Universe is statistically isotropic on large scales.

Brian H. Y. Cheng, Donniel C. Cruz, Otto A. Hannuksela, Davendra S. Hassan, Christian Heiderijk, Leo Q. Hu, Souvik Jana, Jinwon Kim, Albert K. H. Kong, Peony K. K. Lai, Samuel C. Lange, Samson H. W. L (…)2026-04-21⚛️ gr-qc

Clock Noise Cancellation in Heterodyne Links between Optical Cavities for Space-Borne Gravitational-Wave Telescopes

This paper proposes and validates a clock noise cancellation scheme for space-borne gravitational-wave telescopes using heterodyne links between optical cavities, which eliminates clock jitter by combining positive and negative beat-note signals to achieve the required sensitivity in the decihertz band without additional modulation.

Yutaro Enomoto, Subaru Shibai, Kiwamu Izumi2026-04-21🔬 physics.optics

Including higher-order modes in a quadrupolar eccentric numerical relativity surrogate using universal eccentric modulation functions

This paper introduces the \texttt{gwNRHME} framework, which leverages universal eccentric modulation functions to extend quasi-circular numerical relativity surrogates into multi-modal, non-spinning eccentric waveform models (specifically \model{}) that achieve high accuracy against numerical relativity simulations while also providing analytical tools for eccentricity evolution.

Tousif Islam, Adhrit Ravichandran, Peter James Nee, Scott E. Field, Vijay Varma, Harald P. Pfeiffer, Andrea Ceja, Noora Ghadiri, Lawrence E. Kidder, Prayush Kumar, Marlo Morales, Abhishek Ravishankar (…)2026-04-21⚛️ gr-qc

Yukawa scalar self energy at two loop and ϕ2\langle \phi^2 \rangle in the inflationary de Sitter spacetime

This paper computes the two-loop Yukawa scalar self-energy and the resulting loop-corrected coincident two-point correlation function ϕ2\langle \phi^2 \rangle in inflationary de Sitter spacetime, demonstrating that the leading secular growth scales as ln4a\ln^4 a and yields a bounded, monotonically decreasing expectation value that implies an increasing dynamically generated scalar mass with stronger coupling.

Sourav Bhattacharya, Moutushi Dutta Choudhury2026-04-21⚛️ hep-th