A5040441993- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Galaxies: Formation, Evolution, Phenomena
- Radio Astronomy Observations and Technology
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Chemical Reactions and Isotopes
- Atomic and Subatomic Physics Research
- Black Holes and Theoretical Physics
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Relativity and Gravitational Theory
- Radiation Detection and Scintillator Technologies
Centre for Cosmology and Particle Physics Phenomenology
2025
New York University
2025
Tel Aviv University
2025
Johns Hopkins University
2020-2024
A bstract We explore the cosmic birefringence signal produced by an ultralight axion field with a small CP-violating coupling to bulk SM matter in addition usual CP-preserving photon coupling. The change vacuum expectation value of between recombination and today results frequency-independent rotation plane CMB linear polarization across entire sky. While many previous approaches rely on rolling from large initial value, couplings considered this work robustly generate regardless conditions,...
Early dark energy solutions to the Hubble tension introduce an additional scalar field which is frozen at early times but becomes dynamical around matter-radiation equality. In order alleviate tension, scalar’s share of total density must rapidly shrink from <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mo>∼</a:mo><a:mn>10</a:mn><a:mo>%</a:mo></a:mrow></a:math> onset matter domination <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"...
The superradiant instability of black hole space-times has been used to place limits on ultra-light bosonic particles. We show that these are model dependent. While the initial growth mode is gravitational and thus independent, ability a limit new particles requires grow unhindered large number density. Non-linear interactions between particle other light degrees freedom mediated through higher dimension operators can damp this growth, eliminating limit. However, non-linearities may also...
Self-interactions within the dark sector could clump matter into heavy composite states with low number density, leading to a highly suppressed event rate in existing direct detection experiments. However, large interaction cross section between such ultraheavy (UHDM) and standard model results distinctive compelling signature; long, straight damage tracks as they pass through scatter matter. In this work, we propose using geologically old quartz samples large-exposure detectors for UHDM. We...
Gravitational-wave (GW) detectors that monitor fluctuations in the separation between inertial test masses (TMs) are sensitive to new forces acting on those TMs. Ultralight dark-photon dark matter (DPDM) coupled $U(1)_B$ or $U(1)_{B-L}$ charges supplies one such force oscillates with a frequency set by DPDM mass. GW operating different bands thus mass ranges. A recent detection proposal based monitoring of certain asteroids inner Solar System would have sensitivity $\mu$Hz frequencies...
The tentative identification of approximately ten relativistic anti-helium cosmic-ray events at AMS-02 would, if confirmed, challenge our understanding the astrophysical synthesis heavy anti-nuclei. We propose a novel scenario for enhanced production such anti-nuclei that is triggered by isolated, catastrophic injections large quantities energetic Standard Model (SM) anti-quarks in galaxy physics beyond (BSM). demonstrate SM anti-nucleosynthetic processes occur resulting rapidly expanding,...
Subcomponent millicharged dark matter that cools baryons via Coulomb interactions has been invoked to explain the EDGES anomaly. However, this model is in severe tension with constraints from cosmology and stellar emissions. In work, we consider consequences of these particles existing composite Q-balls. The relevant degrees freedom at high temperature are minuscule elementary charges, which fuse low temperatures make up Q-balls larger charge. These serve as cooling sufficiently account for...
The tentative identification of approximately ten relativistic antihelium (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mover accent="true"><a:mi>He</a:mi><a:mo stretchy="true">¯</a:mo></a:mover></a:math>) cosmic-ray events at AMS-02 would, if confirmed, challenge our understanding the astrophysical synthesis heavy antinuclei. We propose a novel scenario for enhanced production such antinuclei that is triggered by isolated, catastrophic injections large quantities...
Early dark energy solutions to the Hubble tension introduce an additional scalar field which is frozen at early times but becomes dynamical around matter-radiation equality. In order alleviate tension, scalar's share of total density must rapidly shrink from $\sim 10\%$ onset matter domination $\ll 1\%$ by recombination. This typically requires a steep potential that imposed $\textit{ad hoc}$ rather than emerging concrete particle physics model. Here, we point out alternative possibility:...
We explore the cosmic birefringence signal produced by an ultralight axion field with a small CP-violating coupling to bulk SM matter in addition usual CP-preserving photon coupling. The change vacuum expectation value of between recombination and today results frequency-independent rotation plane CMB linear polarization across entire sky. While many previous approaches rely on rolling from large initial value, couplings considered this work robustly generate regardless conditions, sourcing...