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Majorana zero modes (MZMs) are promising for topological quantum computation, with vortices in topological superconductors serving as a leading platform. Recent experiments show that integer Abrikosov vortices in iron-based superconductors can split into fractional vortices (FVs) carrying fractional flux quanta. We show that due to topological protection, MZ…

Electronic liquid crystals, such as stripe phases and nematics, are self-organized states of matter with spontaneously broken rotational symmetry. They are expected to emerge in a doped Mott insulator as a compromise between short- and long-range Coulomb interactions, and are believed to be intimately connected to the emergence of high temperature supercondu…

We simulate the gravitational lensing of gravitational waves (GWs) by a Kerr black hole using a $(1+1)$-dimensional time-domain mode-sum approach. To enable efficient explicit time evolution, we implement a localized hyperboloidal foliation combined with a static field redefinition, ensuring bounded characteristic speeds across an extended, uniform tortoise-…

This paper investigates the energy-flux noise induced by imperfections of the Gaussian beam (GB) in the Li-Baker high-frequency gravitational wave (HFGW) detector. Modeling these imperfections with higher-order Laguerre-Gaussian (LG) beams, we analytically derive the resulting noise-to-signal ratio for both co- and cross-polarized $\mathrm{LG}_{nl}$ modes. I…

We study scalar-induced gravitational waves (SIGWs) in a spatially covariant gravity model with two tensorial degrees of freedom, minimally coupled to a $k$-essence scalar field. For the parameter choice considered during radiation domination, the quadratic tensor action coincides with that of general relativity (GR). We derive the scalar transfer functions …

Space-based gravitational-wave detectors compare laser phases exchanged between distant spacecraft. Offset phase locking keeps beatnotes in the phasemeter band, while time-delay interferometry suppresses laser frequency noise. A disturbance of one reference can degrade the functions that depend on it, making robustness an additional criterion for choosing a …

TianQin, a space-borne gravitational wave observatory, is designed to detect gravitational-wave signals via laser interferometry. As the inhomogeneous space plasma surrounds the inter-satellite laser links, the propagation of the laser in space plasma can introduce pointing error noise. In this work, we quantitatively assess the effect of plasma on the point…

The field of gravitational-wave data analysis heavily relies on Bayes factors to make statements about astrophysical effects in events detected by the LIGO-Virgo-KAGRA collaboration. This is true on an event level, for example when discussing the potential detection of precession or eccentricity, as well as on a population level. For the latter, perhaps the …

Binary neutron star (BNS) and black hole--neutron star mergers are among the most important multimessenger sources. Observations of these events could provide valuable insights into several unresolved phenomena, ranging from the efficiency of magnetic field amplification during and after mergers to the formation of magnetars and jets. Understanding these phe…

We show that the jittering-jets explosion mechanism (JJEM) can qualitatively reproduce the shape of the black hole (BH) mass distribution observed by LIGO-Virgo-KAGRA and quantitatively reproduce the peak around $M_{p1} \simeq 10 M_\odot$. To show this, we construct a toy model that captures the JJEM physics that explodes all massive stars, even when BHs for…

The outcome of black hole--neutron star (BHNS) mergers is studied using a general-relativistic mass-shedding condition in the Kerr spacetime, which determines the tidal-disruption radius from the mass ratio, the black hole (BH) spin, the neutron star (NS) compactness, and the ratio of central to average density, $η=\frac{ρ_{c}}{\barρ}$. Comparing this radius…

`Adding colour'' to the gravitational-wave sky by probing unexplored frequency bands has the potential to unveil new and unexpected phenomena in the Universe. The microhertz band, between pulsar timing arrays and LISA, is a particularly attractive target: it should host the extension of the signal recently found by pulsar timing arrays (if it is generated by…

Machine learning (ML) techniques are increasingly explored to analyse gravitational wave (GW) data expected from the Laser Interferometer Space Antenna (LISA). At the same time, advances in quantum computing have stimulated interest in quantum machine learning as a potential alternative to conventional approaches. We investigate the applicability of quantum,…

We carry an in-depth analysis of the gravitational wave (GW) emission of cosmic string cusps, going beyond the seminal work of Damour and Vilenkin. We identify two features that, to the best of our knowledge, have not been described in the literature: first the GWs emission from a cusp, at any given frequency, is not concentrated inside a cone but instead dr…

Cosmic strings and cosmic superstrings could have formed in the early universe. In a particular class of models, the tension associated with these defects is time dependent, either because the strings themselves are composed of evolving moduli fields, or because they are directly coupled to evolving scalar fields leading to an effective time dependence in th…

The inverse Gertsenshteǐn-Zel'dovich effect describes the conversion of gravitational waves into electromagnetic waves in the presence of a background electromagnetic field. This effect has primarily been studied for constant background electromagnetic fields. In this work, we develop a general formalism for calculating the components of the electric and mag…

We use the more than 2000 full numerical-relativity simulations included in the fifth release of the RIT binary-black-hole waveform catalog to perform Bayesian parameter estimation, via the rapid iterative fitting algorithm (RIFT), for the gravitational-wave events GW190521 and GW231123. We revisit GW190521, which has previously been identified as potentiall…

We develop a new method to construct the tree-level Compton amplitude for gravitational-wave scattering off a Kerr black hole in post-Minkowskian effective field theory. Building on previous computations that required physical consistency of the amplitude, the method uses wave scattering functions from black hole perturbation theory to uniquely determine add…

Gravitational waves as one approaches Schwarzschild null infinity are the core of our investigation, treated as the spin-weighted generalisation of a massless scalar field. In particular, we compute their full spectrum, consistent with observations coming from LIGO and VIRGO experiments. This paper continues recent work by the authors, where the Poincaré asy…

We present posterior-landscape, a Python framework to identify and characterize morphological features in two-dimensional probability densities. The framework combines concepts from topological data analysis, statistical density-ridge estimation, and scale-space image analysis. It extracts localized concentrations, valleys, ridges, and changes of slope; for …

The composition of dense matter in neutron star interiors remains uncertain, with the possible appearance of the non-strange $Δ$ resonances providing an important source of theoretical uncertainty. In this work, we investigate the gravitational wave signatures of hyperonic neutron stars containing $Δ$ baryons within a density-dependent relativistic mean-fiel…

Newton's law of universal gravitation describes the attraction between two masses through an inverse-distance potential. In Einstein's theory gravity gravitates: each mass reshapes the spacetime geometry through which the other acts. More than a century later, extracting the two-body interaction from this coupled geometry remains a fundamental analytical cha…

We establish a unified analytic framework for anisotropic overlap reduction functions (ORFs) of arbitrary finite-delay time-delay interferometry (TDI) channels in a static, reciprocal, equal-arm equilateral constellation. The construction combines the polynomial constraints for laser-noise cancellation, constellation symmetries, and directional-projection in…

When a static, spherically symmetric configuration is brought close to a marginal-trapping threshold, it develops a long throat. As the nondegenerate minimum of $F=1-2m/r$ approaches zero, $F\simeqΔ+β(r-R_M)^2$, the proper length across the throat grows as $-\lnΔ/\sqrtβ$, even though the local curvature stays finite. We study how axial gravitational waves pr…

We investigate the optical properties of a five-dimensional charged anti-de Sitter (AdS) black hole. Using the null geodesic equations, we determine the event horizon and photon sphere radii and the critical impact parameter, showing that all decrease with increasing charge, while the photon sphere radius remains independent of the AdS radius. To avoid depen…

Twinor theory is formulated as a spacetime-based counterpart to twistor theory using holomorphic reductive Cartan geometry modelled on complexified $(A)dS_4$. The fundamental spin-tractor bundle defines Dirac twinors, its symmetric powers define ladder twinors, and their extremal Lorentz components define chiral twinors. The general \textit{twinor field equa…

Measures of geometry like distance and time are staples of classical gravity. While geometric quantities arise broadly in quantum gravity, their graviton corrections are less explored. In this paper, we study geometric observables in perturbative quantum gravity. We form distance and time observables that model measurements, including in the presence of spac…

Many theories beyond the standard model of particle physics predict the existence of weakly-coupled exotic spin-dependent interactions between standard model particles. We use experimental upper bounds on neutron-nucleus parity violation at meV and keV neutron energies in the forward scattering limit described by neutron optics to constrain exotic parity-odd…

Axion like particles (ALPs) are particularly well motivated candidates for dark matter, and physics beyond the Standard Model more generally. However, direct detection remains extremely challenging due to the weakness of their interactions. In this work, we propose to employ space-based optical lattice clock networks (SOLCN), originally targeted to probe the…

We present the first direct computation of the two-loop QCD virtual corrections to the production of a top-antitop quark pair in association with a Higgs boson ($t\bar{t}H$) at the LHC. We focus on the quark-antiquark channel and perform the calculation in the generalised leading-colour approximation. We combine state-of-the-art numerical methods for multilo…

We introduce a probabilistic energy-based Neural Network (NN) for uncertainty-aware classification in collider analyses. Standard discriminative classifiers can give highly confident predictions even for events that are different from the data used during training. Energy-Based Models provide an alternative by assigning an energy score to each event, which m…

The concept is presented of making at the FCC-$ee$ (or CEPC) facility $μ^+e^-$ collisions at the centre-of-mass energy between 1 and 2 TeV and the average luminosity above $10^{34}$cm$^{-2}$s$^{-1}$, concurrently to the $e^+e^-$ collisions. First, a concise scientific motivation is given, including the exciting prospect of measurements of the Higgs boson sel…

Multiterminal Josephson junctions have recently attracted substantial attention. The ability to study Andreev bound states in a multi-phase parameter space opens up exciting avenues for generating topologically non-trivial phases in superconducting devices. A particularly interesting case is the trijunction based on a topological insulator (TI), which is pre…

We prove that the three-dimensional chiral $\Z_p$ Clifford quantum cellular automata of Haah and of Sun--Yang--Wang--Tantivasadakarn--Chen are, for every odd prime $p$, not finite-depth quantum circuits, even after tensoring with arbitrary ancillary degrees of freedom and composing with translations. Previously such statements were known only inside the Clif…

We extend the generalized transfer-matrix method introduced in [H. Ghaemi-Dizicheh, Phys.\ Rev.\ B \textbf{107}, 125155 (2023)] to one-dimensional spinful non-Hermitian tight-binding lattices with matrix-valued Abelian and non-Abelian gauge couplings. We derive a minimal channel-resolved transfer matrix and identify its eigenvalues with the generalized Bloch…

We study a spin-polarized moiré Chern band of twisted MoTe$_2$ with short-range repulsion, finding superconductivity proximate to a fractional Chern insulator at filling $ν=2/3$ and a topological charge density wave at $ν=3/4$. Exact diagonalization reveals pair binding over $0.7\lesssimν\lesssim0.77$, consistent with experiment, along with finite superfluid…

Topological Calderbank-Shor-Steane (CSS) codes in more than two spatial dimensions offer features useful for fault-tolerant quantum computation, such as transversal non-Clifford gates and single-shot decoding, but a systematic understanding of them is still lacking. One approach is to decouple a code: map it to a stack of higher-form toric codes by a finite-…

We develop an algebraic theory of fusion, mobility, and statistics in abelian gapped fracton orders and topological phases. The framework generalizes the algebraic description of abelian anyons to systems with restricted-mobility and spatially extended excitations. We consider translation-invariant bosonic systems whose pointlike and extended excitations hav…

The ground state of an ideal gas of anyons with statistical angle $θ\in(0,π)$ is a long-standing open problem, with renewed interest from the recent observations of fractional Chern insulators. In this work we construct variational wavefunctions that build in the exact anyon statistics and combine theory-guided composite-boson, composite-fermion and parton w…

Quantum entanglement is a fundamental resource that gives rise to correlations with no classical counterpart in strongly correlated fermionic systems. However, its characterization in mixed quantum states remains challenging. Established entanglement diagnostics, such as logarithmic negativity, are computationally demanding in interacting systems, and their …