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Author(s): Dongjun Li, Colin Weller, Patrick Bourg, Michael LaHaye, Nicolás Yunes, and Huan Yang Extreme-mass-ratio binaries are important sources of gravitational waves (GW) for space-based GW detectors such as LISA. Employing the newly developed modified Teukolsky formalism, the present paper develops a systematic method for computing scalar radiation from binary inspirals into supermassive black holes in a scalar cloud environment. [Phys...

Author(s): Qu Cao and Fan Zhu Calculating higher-loop scattering amplitudes in pure Yang-Mills theory is a long-standing challenge. By using a novel geometric framework for scattering amplitudes, the authors develop a recursive method based on “cut equations” to compute all-loop integrands in pure Yang-Mills theory in the limit of large number of colors (planar limit). They explicitly provide the results for the two-loop five-point integrand....

Author(s): Keisuke Inomata, Marc Kamionkowski, Kentaro Kasai, and Bibhushan Shakya In this paper, the authors discuss a new source of gravitational waves from first order phase transitions. The collision of bubbles in the new phase can efficiently produce particles that couple to the background field undergoing the transition, transferring a significant amount of the released vacuum energy into particle populations that long outlive the bubbles...

Author(s): David Camarena, Kylar Greene, John Houghteling, and Francis-Yan Cyr-Racine The authors use the latest Baryon Acoustic Oscillation (BAO)- and supernova-based distance data to extend ΛCDM, demonstrating that local cosmological overdensities can provide an alternative explanation to evolving Dark Energy’s “phantom crossing”. [Phys. Rev. D 112, 083526] Published Tue Oct 14, 2025

Author(s): Ian Holst, Gordan Krnjaic, and Huangyu Xiao Light Primordial Black Holes (PBH) can dominate the universe before the onset of the radiation epoch and may evaporate prior to Big Bang Nucleosynthesis (BBN). The authors show that if this PBH-dominated phase lasts sufficiently long, PBHs can form dense clusters whose mergers exhibit runaway behavior, producing massive black holes that survive beyond BBN. Such relics can significantly alter...

Author(s): Kai-Peng Lu and H. Lü Black holes aren’t just cold graves of gravity – they have temperature and entropy. Previous studies have emphasized black holes’ role as the most entropic objects in the universe, that the entropy of a region of space is bounded above by the area that encloses it. This work instead suggests a thermodynamic constraint, that black hole entropy is bounded above by their specific heat. The bound is rigorously proven...

Author(s): N. A. Moraga, F. Castillo, D. D. Ofengeim, A. Reisenegger, J. A. Valdivia, M. E. Gusakov, E. M. Kantor, and A. Y. Potekhin Magnetars are neutron stars with extremely strong magnetic fields; typically they are about 1000x stronger than the “garden variety” radio pulsars. They are also extremely hot and bright and it is generally thought that this extra luminosity is powered by the decay of their strong magnetic fields. The authors study...