相关论文: Electromagnetic Signatures of Dark Photon Superrad…

Dark matter may be charged under dark electromagnetism with a dark photon that kinetically mixes with the Standard Model photon. In this framework, dark matter will collect at the center of the Earth and annihilate into dark photons, which…

Within quantum-gravity approaches and beyond, different mechanisms for singularity resolution in black holes exist. Under a set of assumptions that we spell out in detail, these mechanisms leave their imprint in shadow images of spherically…

We study the relation between obscuration and supermassive black hole (SMBH) growth using a large sample of hard X-ray selected Active Galactic Nuclei (AGN). We find a strong decrease in the fraction of obscured sources above the Eddington…

In this paper, we provide a simple and modern discussion of rotational superradiance based on quantum field theory. We work with an effective theory valid at scales much larger than the size of the spinning object responsible for…

Dark photons, a generic class of light gauge bosons that interact with the Standard Model (SM) exclusively through kinetic mixing, arise naturally in many gauge extensions of the SM. Motivated by these theoretical considerations, we present…

The dark photon is a new hypothetical gauge boson arising in extensions of the Standard Model, and constitutes a compelling dark matter candidate. As dark photon dark matter (DPDM), it can interact with electromagnetic fields via kinetic…

In this study, we examine the phenomenon of photon axion conversion occurring in the spacetime surrounding a black hole. Specifically, we focus on the potential existence of a magnetic field around the supermassive black hole M87*, which…

Recently, it was shown by Danielson-Satishchandran-Wald (DSW) that for the massive or charged body in a quantum spatial separated superposition state, the presence of a black hole can decohere the superposition inevitably towards capturing…

Black hole superradiance provides a window into the dynamics of light scalar fields and their interactions close to a rotating black hole. Due to the rotation of the black hole, the amplitude of the scalar field becomes magnified, leading…

Starting from the evidence that dark matter indeed exists and permeates the entire cosmos, various bounds on its properties can be estimated. Beginning with the cosmic microwave background and large scale structure, we summarize bounds on…

At any epoch, particle physics must be open to completely unexpected discoveries, and that is reason enough to extend the reach of searches for ultra-high energy (UHE) photons. The observation of a population of photons with energies $E…

Annihilations of weakly interacting dark matter particles provide an important signature for the possibility of indirect detection of dark matter in galaxy halos. These self-annihilations can be greatly enhanced in the vicinity of a massive…

We show that highly spinning primordial black holes of mass $M\sim 10^{12}$ kg, potentially born in a matter-dominated era after inflation, can produce clouds of pions in their vicinity via the superradiant instability, with densities up to…

Use of super-radiance in BH physics, so dE/dt < 0 specifies conditions for a mass of a graviton being less than or equal to 10^ - 65 grams, and also allows for determing what role additional dimensions may play in removing the datum that…

In supersymmetric theories the mass of any state is bounded below by the values of some of its charges. The corresponding bounds in case of Schwarzschild and Reissner-Nordstr\"om black holes are known to coincide with the requirement that…

Ultralight bosons near rotating black holes can undergo significant growth through superradiant energy extraction, potentially reaching field values close to the Planck scale and transforming black holes into effective transducers for these…

In supergravity, charged rotating black holes are generically driven towards becoming extremal and supersymmetric through the emission of Hawking radiation. Eventually, as the black hole approaches the BPS bound and is close to becoming…

Dark matter can be captured by celestial objects and accumulate at their centers, forming a core of dark matter that can collapse to a small black hole, provided that the annihilation rate is small or zero. If the nascent black hole is big…

Ultralight bosons can be abundantly produced through superradiance process by a spinning black hole and form a bound state with hydrogen-like spectrum. We show that such a "gravitational atom" typically possesses anomalously large mass…

In our recent companion paper [arXiv:2106.00022], we pointed out a novel signature of ultralight kinetically mixed dark-photon dark matter. This signature is a quasi-monochromatic, time-oscillating terrestrial magnetic field that takes a…