Physical Review D

This paper studies dark matter in a spontaneously broken hidden U(1). The initial overabundant dark matter density is generated through the freeze-out mechanism. Because the subsequent first order phase transition becomes supercooled, the vacuum transition generates entropy, diluting the DM density to its current value. The MeV–GeV transition also produces nano-Hz gravitational waves potentially detectable by pulsar timing arrays such as NANOGrav.

Rotating black holes are thought to drive some of the Universe’s most powerful outflows. A new analytic model finds that the energy carried away from a slowly rotating black hole is set mainly by its spin and magnetic flux at the horizon rather than the details of the surrounding accretion disk.

Advanced cryogenic detectors, e.g. qubit-based sensors or Kinetic Inductance Detectors (KIDs), often offer resolutions larger than a single detected photon’s energy. The authors demonstrate that commonly used statistical methods for calibration of such detectors can introduce systematic biases, leading to inaccurate energy scale and resolution measurements. This stems from an assumption of independence between detector resolution and photon number, which breaks down once realistic effects like position-dependent phonon collection efficiency or Fano fluctuations are taken into account. Finally, a method of correcting for said effects is proposed.

Computing the exact (all corrections included) on-shell action for black holes remains an outstanding problem. Working within the framework of AdS/CFT and using a powerful technique, equivariant localization, the authors evaluate the on-shell action for $D=5$ AdS rotating, charged black holes when higher-derivative quantum corrections are turned on. They also find a precise match with the superconformal index in a Cardy-like limit of the dual N = 1 superconformal field theory in four dimensions.

The JIMWLK evolution equations describe high-energy scattering and the gluon saturation regime of QCD. As an infinite hierarchy of coupled, non-linear equations, approximations are required to make any phenomenological predictions. One widely-used approximation in which one assumes many quantities are Gaussian-distributed random variables, is known to be accurate for a simple class of initial conditions. The authors explicitly demonstrate that this Gaussian approximation fails to accurately describe full JIMWLK evolution beyond this simplest configuration, which may have significant implications for heavy ion collisions.