We investigate the effect of higher-dimensional marginal operators on the thermodynamics of cosmological phase transitions. Focusing on the Abelian Higgs model, we systematically match these operators, which arise at higher orders in the underlying high-temperature expansion of thermal effective field theory, and use field redefinitions to construct a complete, minimal, and gauge-invariant...
Gravitational waves are naturally sourced by hydrodynamical fluctuations in a thermal medium, as the one that filled the universe before recombination. Since the corresponding gravitational wave spectrum is expected to show rapid growth at high frequencies, unprecedented prospects to detect these signals may be offered by proposed interferometers. While the spectral shape is well understood,...
Under the assumption that the recent pulsar timing array evidence for a stochastic gravitational wave (GW) background at nanohertz frequencies is generated by metastable cosmic strings, we analyze the potential of present and future GW observatories for probing the change of particle degrees of freedom caused, e.g., by a supersymmetric (SUSY) extension of the Standard Model (SM). We find that...
The next generation of ground-based gravitational wave detectors, such as the Einstein Telescope and Cosmic Explorer, will enable us to probe the cosmos in unprecedented ways. The design, location, and arm orientation of these detectors significantly influence their sensitivity and performance for various gravitational wave sources. For cosmological studies, the localization and distance...
Extreme mass-ratio inspirals (EMRIs) are one of the major sources of gravitational waves (GWs) that will be detected by LISA. Similar to the compact binary mergers detected by current GW detectors, EMRIs can be used as cosmic rulers to probe the expansion of the Universe and our current cosmological paradigm, the LambdaCDM model. Interestingly, modified gravity theories can affect the...
The field of gravitational-wave cosmology has picked up steam in recent years due to important observations done by LIGO-VIRGO-KAGRA, such as GW150914 and GW170817. However, the absence of a galaxy catalog that is optimized for the purpose of resolving the positions of gravitational-wave sources has been a known issue. This work is part of the newly proposed survey, Sirenas, and aims to create...
