May 15 – 17, 2026
College of Hakka Studies at NYCU, Zhubei, Hsinchu County 國立陽明交通大學客家學院(竹北六家校區)
Asia/Taipei timezone

Testing cosmological isotropy with gravitational waves and gamma-ray bursts

Not scheduled
15m
College of Hakka Studies at NYCU, Zhubei, Hsinchu County 國立陽明交通大學客家學院(竹北六家校區)

College of Hakka Studies at NYCU, Zhubei, Hsinchu County 國立陽明交通大學客家學院(竹北六家校區)

No. 1, Sec. 1, Liujia 5th Rd., Zhubei City, Hsinchu County 302, Taiwan 30272新竹縣竹北市六家五路一段1號
Board: 60

Speaker

Hiu Yeung Cheng (Department of Physics, The Chinese University of Hong Kong)

Description

The cosmological principle asserts that the Universe is statistically isotropic on large scales, while alternative cosmological models can produce anisotropic signatures. Recent studies have suggested tantalising hints of anisotropies in supernova Ia, cosmic microwave background, and gamma-ray burst data, though these remain unconfirmed. We test for cosmological anisotropies using the latest LIGO-Virgo-KAGRA O4a catalog of events and the gamma-ray burst web compilation of gamma-ray bursts. If the cosmological principle holds, the sky localisation and characteristics of the gamma-ray bursts and gravitational waves (masses, luminosities, redshifts) should be statistically isotropic when corrected for selection biases. We analyze the sky distributions and source properties of these transients using angular power spectra, two-point correlation statistics, and Bayesian population tests, and compare the results with synthetic isotropic data. Our work extends previous analyses by incorporating the most recent datasets, the inclusion of other characteristics (e.g. masses) beyond sky positions and multiple complementary tests. We find no significant evidence for anisotropy in the current gravitational wave and gamma-ray burst datasets, consistent with the cosmological principle.

Participate the oral/poster presentation award competition Yes

Author

Hiu Yeung Cheng (Department of Physics, The Chinese University of Hong Kong)

Co-authors

Albert Kong Mr Boris H.-L. Ng (Department of Physics, The Chinese University of Hong Kong) Mr Christian Heiderijk (Department of Physics, City University of Hong Kong) Ms Davendra S. Hassan (Department of Physics, National University of Singapore) Mr Donniel C. Cruz (Department of Physics, De La Salle University, Manila) Dr Gwangeon Seong (Department of Physics, Ewha Womans University) Ms Helen Xian (Department of Physics, The Chinese University of Hong Kong) Ms Jinwon Kim (Department of Physics, Chung-Ang University) Mr Leo Q. Hu (Department of Physics, City University of Hong Kong) Li-Ting Ma (National Tsing-Hua University) Dr Matteo Lulli (Department of Physics, The Chinese University of Hong Kong) Prof. Otto A. Hannuksela (Department of Physics, The Chinese University of Hong Kong) Dr Paul Martens (Department of Physics, The Chinese University of Hong Kong) Ms Peony K. K. Lai (Department of Physics, The Chinese University of Hong Kong) Mr Samson H. W. Leong (Department of Physics, The Chinese University of Hong Kong) Dr Samuel C. Lange (Department of Physics, The Chinese University of Hong Kong) Dr Souvik Jana (Department of Physics, The Chinese University of Hong Kong) Surojit Saha (Institute of Astronomy, National Tsing Hua University, Taiwan) Mr Thomas C. K. Ng (Institute for Gravitational and Subatomic Physics (GRASP), Utrecht University) Dr Yanyan Zheng (Missouri University of Science and Technology)

Presentation materials

There are no materials yet.