Multi-messenger astronomy, the coordinated observation of different classes of signals originating from the same astrophysical event, provides a wealth of information about astrophysical processes. The focus of multi-messenger astronomy has been the search for conventional signals from known fundamental forces and standard model particles, like gravitational waves. In addition to these known...
Ultralight bosonic (ULB) fields with mass $m_{\phi} \ll 1$~eV often arise in theories beyond the Standard Model (SM). If such fields exist, violent astrophysical events that result in emission of gravitational wave, photon, or neutrino signals could also produce bursts of high-density relativistic ULB fields. Detection of such ULB fields in terrestrial or space-based laboratories correlated...
Since dark matter is only known to have gravitational interactions, it may plausibly decay to gravitons on cosmological timescales. Although such a scenario can be easily realized, there are currently no known limits on this possibility based on indirect detection searches. We find that the gravitons produced in dark matter decays can convert to photons in large-scale magnetic fields along the...
I will review some recent developments on the production of high frequency gravitational waves during the reheating stage.
Diamond quantum sensors based on nitrogen-vacancy (NV) centers have attracted great attention owing to their high sensitivity, wide dynamic range, and high spatial resolution. Utilizing these outstanding properties, diamond quantum sensors have recently been proposed for applications in fundamental physics, including dark matter searches and investigations of quantum gravity. In this...
Diamond is a host for various defects, notably the nitrogen-vacancy (NV) centre. This colour centre consists of a substitutional nitrogen and a neighbouring missing carbon atom, and it has electron spin. It is sensitive to various quantities, for example magnetic fields, and as such it finds use as a sensor in many applications, from biology to electronics. Moreover, quantum sensors are...
The search for new physics beyond the Standard Model using quantum sensors relies heavily on the synergy between experimental precision and accurate theoretical modeling. This talk outlines a comprehensive computational infrastructure designed to support these efforts, including complex atomic structure calculations with automated workflows and the consolidation of results into the Portal for...
Lepton flavor violation in neutrinos aka neutrino-oscillation is a telltale signature of Beyond the Standard Model (BSM) physics. If a similar phenomenon is found in the charged leptons as well, that will further consolidate the existence of BSM physics. In this work, we look for signature of charged lepton flavor violation, muon to tau conversion, in the IceCube. Moreover, we set a constraint...
The computation of Casimir forces between material bodies, in principle, requires frequency responses of the permittivities of the materials over a sufficiently wide range. However, particularly for many emerging materials such as Weyl semimetals, the permittivities in high frequencies are not yet known experimentally or accounted for in existing models. In this talk, a computation technique...
Ultralight dark matter is an interesting dark matter candidate at the lowest mass end of the dark matter parameter space. One of the predictions of this model is that dark matter halos should have tightly packed O(1) density fluctuations which oscillate on the de Broglie time and length scales. For masses above ~10^18 eV these oscillations occur on observable timescales. In this talk we will...
Since the first detection of gravitational waves a decade ago, more than 300 events have been reported. The Observing Run 4 (O4) concluded in November 2025, and LIGO, Virgo, and KAGRA have since begun upgrades aimed at further improving their sensitivities. These upgrades are expected to improve sky localization, which will aid multi-messenger observations. Moreover, laser interferometric...
Since SN1987A, we know that supernovae (SNs) produce burst of neutrinos which can be detected several minutes to hours before the electromagnetic burst. Detecting this neutrino burst would provide valuable information on the supernova explosion mechanism and allow to give an early warning of the imminent eletromagnetic burst arrival to the astronomer community. The Super-Kamiokande experiment,...
Dark matter (DM) annihilation has been proposed as an alternate heat source to fusion in the first stars. These "dark stars" (DS) are modeled to become supermassive and survive for astronomically long timescales. At the end of their lives they are expected to collapse directly to black holes, seeding the supermassive black holes (SMBH) at the centers of modern galaxies. We study the diffuse...
Lorentz symmetry, a foundational principle in both the Standard Model of particle physics and general relativity, is challenged by certain quantum gravity models that predict possible violation. Detecting these tiny Lorentz symmetry violation, or Lorentz violation, has become a global scientific interest, with interference experiments and other precise systems offering the sensitivity needed...
Quantum metrology is a promising application of quantum technologies, enabling the precise measurement of weak external fields at a local scale. In typical quantum sensing protocols, a qubit interacts with an external field, and the amplitude of the field is estimated by analyzing the expectation value of a measured observable. Sensitivity can, in principle, be enhanced by increasing the...
TES microcalorimeters offer excellent energy resolution over a wide energy bandwidth, with a reasonable collecting area enabled by multiplexing techniques. This detector technology has now matured to the point where it can be effectively applied at accelerator facilities. In particular, we have explored its use in charged-particle beamlines, such as kaon and muon beams. In this talk, I will...
Since the first detection of gravitational waves from binary black hole mergers, a key question has been how such massive black holes—often exceeding 30 M⊙—are formed in the Universe. Recent results from GWTC-4 have even reported multiple black holes with masses beyond 100 M⊙, posing new challenges to our understanding of stellar evolution and compact-object formation. In this talk, I will...
KamLAND is a kiloton-scale liquid-scintillator detector located in the Kamioka underground laboratory in Japan, originally designed to study reactor antineutrino oscillations. Over more than two decades of operation, KamLAND has evolved into a versatile facility for neutrino and rare-event physics. In this talk, I will give an overview of recent and ongoing results on astrophysical and...
