The mode profile of a coupled optical cavity often exhibits a resonant doublet, which arises from the strong coupling between its subcavities. Traditional readout methods rely on setting fields of different frequencies to be resonant in either subcavity, which is challenging in the case of strong coupling. In this regime, the coupled cavity behaves as a single resonator, and a field must be resonant in all its parts. Consequently, specialized sensing schemes are necessary to control strongly coupled cavities. To address this issue, we propose a novel technique for the relative measurement of the degrees of freedom of a strongly coupled cavity. Our approach enables simultaneous frequency stabilization and fine-tuning of frequency splitting in the resonant doublet. Overall, our proposed technique offers a promising solution to control the properties of coupled cavities, facilitating advanced applications in the fields of gravitational-wave detection, quantum cavity optomechanics, and other related areas.

We present a systematic approach to determine all relativistic phases up to $\mathcal{O}(c^{-2})$ in light-pulse atom interferometers in weakly curved spacetime that are based on elastic scattering—namely, Bragg diffraction and Bloch oscillations. Our analysis is derived from first principles using the parametrized post-Newtonian formalism. In the treatment developed here, we derive algebraic expressions for relativistic phases for arbitrary interferometer geometries in an automated manner. As case studies, we consider symmetric and antisymmetric Ramsey-Bordé interferometers, as well as a symmetric double diffraction interferometer with baseline lengths of 10 m and 100 m. We compare our results to previous calculations conducted for a Mach-Zehnder interferometer.

Bayesian model averaging is a practical method for dealing with uncertainty due to model specification. Use of this technique requires the estimation of model probability weights. In this work, we revisit the derivation of estimators for these model weights. Use of the Kullback-Leibler divergence as a starting point leads naturally to a number of alternative information criteria suitable for Bayesian model weight estimation. We explore three such criteria, known to the statistics literature before, in detail: a Bayesian analog of the Akaike information criterion which we call the BAIC, the Bayesian predictive information criterion, and the posterior predictive information criterion (PPIC). We compare the use of these information criteria in numerical analysis problems common in lattice field theory calculations. We find that the PPIC has the most appealing theoretical properties and can give the best performance in terms of model-averaging uncertainty, particularly in the presence of noisy data, while the BAIC is a simple and reliable alternative.

We study the interplay between the flow and hydrodynamic gradients in jet quenching at first order in opacity. We find that the mixed flow-gradient contributions in jet quenching are enhanced by the medium length and survive in the eikonal limit, dominating over other medium evolution effects. The resulting modification to the jet quenching parameter and energy loss rate can be substantial, leading to ample phenomenological implications. We also compute the leading corrections to the jet broadening due to the flow velocity gradients and consider the leading gradient effects in the medium-induced branching for general kinematics, extending the recent considerations of jets in inhomogeneous media. These results can be straightforwardly coupled to matter simulations, providing new opportunities for jet tomography in heavy-ion collisions.

While jet quenching in relativistic heavy-ion collisions has been extensively studied over decades, the polarization of quenched hadrons has rarely been discussed. It has recently been proposed that the correlations of dihadron polarization in $e^{+}{e}^{-}$ and $pp$ collisions provide a novel probe of the longitudinal spin transfer from hard partons to hadrons without requiring the colliding beams to be polarized. To support realistic experimental measurement of dihadron polarization with sufficient luminosity, we extend the aforementioned study to relativistic heavy-ion collisions by convoluting the vacuum fragmentation of partons with their energy loss inside the quark-gluon plasma. We find that while the correlation functions of $\mathrm{\Lambda }\text{−}\mathrm{\Lambda }$ (or $\mathrm{\Lambda }\text{−}\overline{\mathrm{\Lambda }}$) polarization in peripheral collisions is consistent with those in $pp$ collisions, clear enhancement can be seen in central collisions. These correlation functions appear sensitive to different assumptions in the de Florian-Stratmann-Vogelsang (DSV) of parton fragmentation functions and, therefore, could place additional constraints on the spin-dependent fragmentation functions of quarks and gluons. The correlation of dihadron polarization has also been explored in ultraperipheral heavy-ion collisions, which provides a cleaner probe of fragmentation functions of quarks produced by energetic photon-photon and photon-Pomeron interactions.

The exploration of critical phenomena in phase transitions of strongly interacting matter governed by quantum chromodynamics (QCD) is one of the goals of present ultrarelativistic heavy-ion collision experiments at BNL and CERN. The key research direction is to locate the putative critical point on the phase diagram of QCD linked to the chiral symmetry restoration at finite temperature and/or density. One of the main theoretical tools used for this purpose is the fluctuations of conserved charges, such as the net-baryon number. However, due to experimental limitations, analyses of heavy-ion collision data suffer from a very doubtful basing of the net-proton number being a proxy for the total net-baryon number fluctuations. In this work, we use the parity doublet model to investigate the fluctuations of the net-baryon number density in hot and dense hadronic matter. The model accounts for chiral criticality within the mean-field approximation. We focus on the qualitative properties and systematics of the first- and second-order susceptibility of the net-baryon number density, and their ratios for nucleons of positive and negative parity, as well as their correlator. We show that the fluctuations of the positive-parity nucleon do not necessarily reflect the fluctuations of the total net-baryon number density at the phase boundary of the chiral phase transition. We also investigate the nontrivial structure of the correlator. Furthermore, we discuss and quantify the differences between the fluctuations of the net-baryon number density in the vicinity of the chiral and liquid-gas phase transition in nuclear matter. We indicate a possible relevance of our results with the interpretation of the experimental data on net-proton number fluctuations in heavy-ion collisions.

Gravitational wave (GW) astronomy has experienced remarkable growth in recent years, driven by advancements in ground-based detectors. While detecting compact binary coalescences (CBCs) has become routine, searching for more complex ones, such as mergers involving eccentric and precessing binaries and subsolar mass binaries, has presented persistent challenges. These challenges arise from using the standard matched filtering algorithm, whose computational cost increases with the dimensionality and size of the template bank. This urges the pressing need for faster search pipelines to efficiently identify GW signals, leading to the emergence of the hierarchical search strategy that reduces the computational cost of matched filtering in the search. This method looks for potential candidate events using a coarse bank of templates (with reduced density and sampling rate) in the first stage, which are then followed up in the second stage with the usual template bank (with optimal density and sampling rate) but only in the neighborhood of the parameter space of the candidate events identified in the first stage. Although the hierarchical search was demonstrated to speed up the standard pycbc analysis by more than a factor of 20 in a previous work outlined in Soni et al. [Phys. Rev. D 105, 064005 (2022)], assigning statistical significance to detected signals, especially in the presence of non-Gaussian noise, was done in a heuristic way. This article introduces a method for background estimation in a two-stage hierarchical search. Our method models the distribution of background triggers obtained from time-shifted triggers in a two-detector network. This modeling precisely aligns with the background distribution across critical signal-to-noise ratios (SNRs), where distinguishing between signal and noise is particularly challenging. It incorporates a fitting procedure to extrapolate to higher detection statistic values. Using this background estimation approach, we assessed the sensitivity of the hierarchical search compared to the standard pycbc search. Our findings indicate that the hierarchical search attains a sensitive volume-time product comparable to the standard two-detector pycbc search. This equivalence holds for an inverse false alarm rate of 10 years by a factor ranging from $0.99\pm 0.144$ and $1.02\pm 0.141$ within the chirp mass range of approximately 1.4 to $20M_{\odot }$. Our methodology accomplishes this while substantially reducing the overall computational cost of the analysis. Specifically, our pipeline exhibits a remarkable speed-up, nearly 13 times faster than pycbc analysis, including background estimation.

Quantum gravity theories predict deformations of black hole solutions relative to their classical counterparts. A model-independent approach was advocated in Binetti et al. [Effective theory of quantum black holes, Phys. Rev. D 106, 046006 (2022)] that uses metric deformations parametrized in terms of physical quantities, such as the proper distance. While such a description manifestly preserves the invariance of the space-time under coordinate transformations, concrete computations are hard to tackle since the distance is defined in terms of the deformed metric itself. In this work, for spherically symmetric and static metrics, we provide a self-consistent framework allowing us to compute the distance function in close vicinity to the event horizon of a black hole. By assuming a minimal degree of regularity at the horizon, we provide explicit (series) expansions of the metric. This allows us to compute important thermodynamical quantities of the black hole, such as the Hawking temperature and entropy, for which we provide model-independent expressions, beyond a large mass expansion. Moreover, imposing for example the absence of curvature singularities at the event horizon leads to nontrivial consistency conditions for the metric deformations themselves, which we find to be violated by some models in the literature.

We investigate the proposal that the rise with energy of the ratio of the exclusive photoproduction cross sections of vector mesons $\mathrm{\Psi }(2s)$ and $J/\mathrm{\Psi }$ can serve as an indicator for the presence of high gluon densities and associated nonlinear high energy evolution; we study this proposal for both photoproduction on a proton and a lead nucleus. While previous studies were based on unintegrated gluon distributions subject to linear (Balitsky-Fadin-Kuraev-Lipatov) and nonlinear (Balitsky-Kovchegov) evolution equations, the current study is based on the Golec-Biernat Wüsthoff and Bartels Golec-Biernat Kowalski models, which allows us to assess more directly the relevance of nonlinear corrections for the description of the energy dependence of the photoproduction cross section. We find that the rise of the ratio is directly related to the presence of a node in the $\mathrm{\Psi }(2s)$ wave function and only manifests itself for the complete nonlinear models, while it is absent for their linearized versions. We further provide predictions based on leading order collinear factorization and examine to which extent such an approach can mimic a ratio rising with energy. We also provide a description of recent ALICE data on the energy dependence of the photonuclear $J/\mathrm{\Psi }$ production cross section and give predictions for the energy dependence of the ratio of $\mathrm{\Psi }(2s)$ and $J/\mathrm{\Psi }$ photoproduction cross sections for both scattering on a proton and a lead nucleus.

The ADMX Collaboration gathered data for its Run 1A axion dark matter search from January 2017 to June 2017, scanning with an axion haloscope over the frequency range 645–680 MHz ($2.66–2.81\mathrm{\mu }\mathrm{eV}$ in axion mass) at Dine-Fischler-Srednicki-Zhitnitskii (DFSZ) sensitivity. The resulting axion search found no axionlike signals comprising all the dark matter in the form of a virialized galactic halo over the entire frequency range, implying lower bound exclusion limits at or below DFSZ coupling at the 90% confidence level. This paper presents expanded details of the axion search analysis of Run 1A, including review of relevant experimental systems, data-taking operations, preparation and interpretation of raw data, axion search methodology, candidate handling, and final axion limits.

In this paper, we study the implications of precise gauge coupling unification on supersymmetric particle masses. We argue that precise unification favors the superpartner masses that are in the range of several TeV and well beyond. We demonstrate this in the minimal supersymmetric theory with a common sparticle mass threshold, and two simple high-scale scenarios; minimal supergravity and minimal anomaly-mediated supersymmetry. We also identify candidate models with a Higgsino or a wino dark matter candidate. Finally, the analysis shows unambiguously that unless one takes foggy naturalness notions too seriously, the lack of direct superpartner discoveries at the LHC has not diminished the viability of supersymmetric unified theories in general nor even precision unification in particular.

The Gribov-Zwanziger prescription applied within Yang-Mills theory is demonstrated to be an efficient method for refining the theory’s infrared dynamics. We study the collisional energy loss experienced by a high-energetic test parton as it traverses through the Grivov plasma at finite temperature. To achieve this, we employ a semiclassical approach that considers the parton’s energy loss while accounting for the backreaction induced by the polarization effects due to its motion in the medium. The polarization tensor of the medium is estimated within a nonperturbative resummation considering the Gribov-Zwanziger approach. The modification of the gluon and ghost loops due to the presence of the Gribov parameter plays a vital role in our estimation. We observe that the nonperturbative interactions have a sizable effect on the parton energy loss. Further, we discuss the implications of our findings in the context of relativistic heavy-ion collisions.

Generalized global symmetries are a common feature of many quantum field theories decoupled from gravity. By contrast, in quantum gravity/the Swampland program, it is widely expected that all global symmetries are either gauged or broken, and this breaking is in turn related to the expected completeness of the spectrum of charged states in quantum gravity. We investigate the fate of such symmetries in the context of 7D and 5D vacua realized by compact Calabi-Yau spaces with localized singularities in M theory. We explicitly show how gravitational backgrounds support additional dynamical degrees of freedom which trivialize (i.e., “break”) the higher symmetries of the local geometric models. Local compatibility conditions across these different sectors lead to gluing conditions for gauging higher-form and (in the 5D case) higher-group symmetries. This also leads to a preferred global structure of the gauge group and higher-form gauge symmetries. In cases based on a genus-one fibered Calabi-Yau space, we also get an F-theory model in one higher dimension with corresponding constraints on the global form of the gauge group.

We investigate the connection between the classical Larmor formula and the quantum Unruh effect by computing the emitted power by a uniformly accelerated charged particle and its angular distribution in the coaccelerated frame. We consider a classical particle accelerated with nonzero charge only for a finite period and then take the infinite-time limit after removing the effects due to the initial charging and final discharging processes. We show that the result found for the interaction rates agrees with previous studies in which the period of acceleration with nonzero charge was taken to be infinite from the beginning. We also show that the power and angular distribution of emission, which is attributed either to the emission or absorption of a Rindler photon in the coaccelerated frame, is given by the Larmor formula, confirming that, at tree level, it is necessary to take into account the Unruh effect in order to reproduce the classical Larmor radiation formula in the coaccelerated frame.

In this article, we will for the first time model galactic black holes in pure Lovelock gravity. Even though working with higher spacetime dimensions, we assume (implicitly) the Hernquist-type mass profile for the galaxy in such a way that the horizon structure of a pure LoveLock black hole remains intact. In this way, we will model the galactic pure Lovelock black hole with arbitrary dimension ($d$) and order ($N$). Then, we will specialize this technique for critical dimension $d=3N+1$. We want to see how the galactic parameters affect the time domain single, quasinormal modes, photon sphere, innermost stable circular orbits (ISCO), and shadow radius. The time domain signal may allow us to identify the galactic parameters as well as to distinguish them from their isolated pure Lovelock counterparts if it is observed in future generations of gravitational wave measurements. We also calculate Hawking temperature for the same setup and want to see how Hawking’s temperature will be affected due to the presence of a galaxy. It shows that the presence of a galactic halo can quench Hawking temperature.

We present a simple analytical model for studying the collapse of an ultracompact stellar object (regular black hole mimicker with infinite redshift surface) to form a (integrable) black hole, in the framework of general relativity. Both initial and final configurations have the same ADM mass, so the transition represents an internal redistribution of matter without emission of energy. The model, despite being quite idealized, can be viewed as a good starting point to investigate near-horizon quantum physics.

Mergers of binary compact objects, accompanied with electromagnetic (EM) counterparts, offer excellent opportunities to explore varied cosmological models, since gravitational waves (GWs) and EM counterparts always carry the information of luminosity distance and redshift, respectively. $f(T)$ gravity, which alters the background evolution and provides a friction term in the propagation of GWs, can be tested by comparing the modified GW luminosity distance with the EM luminosity distance. Considering the third-generation gravitational-wave detectors, Einstein Telescope and two cosmic explorers, we simulate a series of GW events of binary neutron stars and neutron-star–black-hole binaries with EM counterparts. These simulations can be used to constrain $f(T)$ gravity [especially the power-law model $f(T)=T+\alpha (-T{)}^{\beta }$ in this work] and other cosmological parameters, such as $\beta$ and the Hubble constant. In addition, combining simulations with current observations of type Ia supernovae and baryon acoustic oscillations, we obtain tighter limitations for $f(T)$ gravity. We find that the estimated precision significantly improved when all three datasets are combined ($\mathrm{\Delta }\beta \sim 0.03$), compared to analyzing the current observations alone ($\mathrm{\Delta }\beta \sim 0.3$). Simultaneously, the uncertainty of the Hubble constant can be reduced to approximately 1%.

We use the full-mission Planck PR4 data to measure the CMB lensing convergence ($\kappa$)–thermal Sunyaev-Zel’dovich (tSZ, $y$) cross-correlation signal, $C_{\ell }^{y\kappa }$. This is only the second measurement to date of this signal, following Hill and Spergel [J. Cosmol. Astropart. Phys. 02 (2014) 030]. We perform the measurement using foreground-cleaned tSZ maps built from the PR4 frequency maps via a tailored needlet internal linear combination (NILC) code in our companion paper [F. McCarthy and J. C. Hill, companion paper, Phys. Rev. D 109, 023528 (2024).], in combination with the Planck PR4 $\kappa$ maps and various systematic-mitigated PR3 $\kappa$ maps. A serious systematic is the residual cosmic infrared background (CIB) signal in the tSZ map, as the high CIB—$\kappa$ cross-correlation can significantly bias the inferred tSZ—$\kappa$ cross-correlation. We mitigate this contamination by deprojecting the CIB in our NILC algorithm, using a moment deprojection approach to avoid leakage due to incorrect modeling of the CIB frequency dependence. We validate this method on mm-wave sky simulations. We fit a theoretical halo model to our measurement, finding a best-fit amplitude of $A=0.82\pm 0.21$ (for the highest signal-to-noise PR4 $\kappa$ map) or $A=0.56\pm 0.24$ (for a PR3 $\kappa$ map built from a tSZ-deprojected CMB map), indicating that the data are consistent with our fiducial model within $\approx 1\text{−}2\sigma$. Although our error bars are similar to those of the previous measurement [J. C. Hill and D. N. Spergel, J. Cosmol. Astropart. Phys. 02 (2014) 030], our method is significantly more robust to CIB contamination. Our moment-deprojection approach lays the foundation for future measurements of this signal with higher signal-to-noise $\kappa$ and $y$ maps from ground-based telescopes, which will precisely probe the astrophysics of the intracluster medium of galaxy groups and clusters in the intermediate-mass ($M\sim {10}^{13}–{10}^{14}{h}^{-1}{M}_{\odot }$), high-$z$ ($z\lesssim 1.5$, c.f. $z\lesssim 0.8$ for the tSZ auto-power signal) regime, as well as CIB-decontaminated measurements of tSZ cross-correlations with other large-scale structure probes.

We use the full-mission Planck PR4 data to construct maps of the thermal Sunyaev–Zel’dovich effect (Compton-$y$ parameter) in our Universe. To do so, we implement a custom needlet internal linear combination (NILC) pipeline in a python package, pyilc, which we make publicly available. We publicly release our Compton-$y$ maps, which we construct using various constrained ILC (“deprojection”) options in order to minimize contamination from the cosmic infrared background (CIB) in the reconstructed signal. In particular, we use a moment-based deprojection that minimizes sensitivity to the assumed frequency dependence of the CIB. Our code pyilc performs needlet or harmonic ILC on mm-wave sky maps in a flexible manner, with options to deproject various components on all or some scales. We validate our maps and compare them to the official Planck 2015 $y$ map, finding that we obtain consistent results on large scales and 10–20% lower noise on small scales. We expect that these maps will be useful for many auto- and cross-correlation analyses; in a companion paper, we use them to measure the tSZ—CMB lensing cross-correlation. We anticipate that pyilc will be useful both for data analysis and for pipeline validation on simulations to understand the propagation of foreground components through a full NILC pipeline.