Chiral gravitational wave backgrounds are predicted in many well-motivated mechanisms. We investigate the detection of Chiral GWBs using a network of detectors under arbitrary configurations. We also propose a dipole pulsar timing array, which demonstrates sensitivity to Chiral gravitational wave backgrounds from the nanohertz to microhertz regime.
The early universe is a natural laboratory for high-energy physics, and gravitational waves, as direct probes of this epoch, inherently carry rich information related to high-energy physics. Silk damping, resulting from dissipation in the cosmic fluid, is a significant physical phenomenon in the early universe. In this talk, I will introduce our first study on Silk damping in induced...
The memory burden (MB) effect can dramatically slow black hole evaporation once half of the initial mass is radiated, allowing very light primordial black holes (PBHs) to persist today as dark matter (DM). We probe this scenario across three complementary messengers.
Using LHAASO ultra-high-energy gamma-ray spectra of four Galactic sources, we constrain PBHs with masses 10^9 g. From 10 years...
Large primordial curvature perturbations can produce primordial black holes (PBHs) and inevitably generate a scalar-induced stochastic gravitational-wave background upon horizon re-entry. In this talk, based on our recent work arXiv:2609.12867, we will present constraints from the combined LIGO–Virgo–KAGRA O1–O4a data on two representative inflationary mechanisms for producing such...
The gravitational-wave background (GWB) is a superposition of individually unresolved gravitational-wave (GW) signals arising from both astrophysical and cosmological sources accumulated throughout cosmic history. We refer to the GWB as “stochastic” as it can be characterized statistically as a mean zero stochastic field. For the isotropic GWB search considered here, the GWB is further assumed...
This talk presents Evo-MCTS (arXiv:2508.03661), a framework combining large language models, Monte Carlo tree search, and evolutionary optimization for automated algorithm discovery, using gravitational-wave signal searches as a case study. Through analyses of search trajectories and subsequent audits, we examine how benchmark design influences optimization and how independent validation and...
Cosmic-string loops generate a broadband gravitational-wave background (GWB) that is typically modeled via two distinct formalisms: a discrete harmonic expansion, commonly used in pulsar-timing-array (PTA) studies, and a continuous burst superposition, employed in ground-based GWB searches. In this work, we formally unify the two formalisms, showing that they provide discrete and continuous...
We introduce an alternative approach to gravitational-wave (GW) detection in which GW information is encoded in the orbital angular momentum (OAM) states of photons. Starting from the propagation of vortex light in linearized gravity, we show that interaction with a GW induces transitions from an initial photon OAM state to neighboring OAM sidebands, providing a different optical observable of...
Every rapidly spinning neutron star with slight asymmetry would broadcast a continuous hum of gravitational waves (GW). None of these signals has been detected yet, but the silence itself is measurable: searches now set upper limits on the GW amplitude of dozens of known pulsars, and for a growing subset those limits dig below the energy budget available from the stars' own spin-down. We ask...
Mini-extreme-mass-ratio inspirals (mini-EMRIs), in which a subsolar-mass compact object orbits a much heavier compact object, are long-duration gravitational-wave sources of interest to ground-based detectors. Their signals can remain in band for hours to years, making fully coherent matched-filter searches computationally expensive. Semicoherent time-frequency searches reduce this cost by...
