High Energy Physics (Phenomenology)
Radiative Signature of New Scalar Boson Decays in the $m_{\ell \ell \gamma}$ Spectrum at the LHC
Pramod Sharma, Arnav Chauhan, Mukesh Kumar et al. (+4 more)
We investigate the radiative decay $S \to W^+W^-\gamma$ in the context of the multi-
lepton anomalies and recent indications of a narrow scalar resonance near $m_S = 152 \pm 1~\text{GeV}$ in the $\gamma\gamma$, $Z\gamma$, and $W^+W^-$ channels at the Large
Hadron Collider. These excesses arise in final states containing
leptons, missing transverse momentum, and associated $b$-jets, and motivate a search for a corresponding localized excess in the invariant-mass spectrum of the dilepton–
photon system, $m_{\ell\ell\gamma}$, in events with associated $b$-jets. We use recent CMS measurements of the ${t\bar{t}}\gamma$ differential cross sections~\cite{CMS:2025zbe} to study the $m_{\ell\ell\gamma}$ spectrum and perform a search for a scalar-resonance contribution. A localized excess is observed, compatible with the scalar-resonance hypothesis, with a global significance of $2.7\sigma$ at $m_S = 152~\text{GeV}$. This result provides additional support for the hypothesis of a narrow resonance. The ratio $\sigma(S \to W^+W^-\gamma)/\sigma(S \to W^+W^-) = (2.14 \pm 0.77)$% is extracted. This value is compatible with an enhanced radiative contribution that could arise in scenarios beyond the Standard Model.
Read the full abstract ▾
All authors Pramod Sharma, Arnav Chauhan, Mukesh Kumar, Andreas Crivellin, Sukanta Dutta, Rachid Mazini, Bruce Mellado
Strongly Correlated Electrons
The Interplay of Thermal Melting and Pump Driven Melting of Charge Order: A Two-Temperature Study of the Holstein Model
Debraj Bose, Sankha Subhra Bakshi and Pinaki Majumdar
Charge order driven by electron-
phonon coupling is well understood at
equilibrium but pump-probe experiments raise a new question: how does this order melt and recover after strong photoexcitation? A pump pulse promotes carriers across the charge-order gap and creates a nonequilibrium high-energy electronic population. In a closed system the subsequent dynamics is constrained by energy conservation. In an `open system' - where the system is coupled to a thermal bath at some temperature $T_{\rm bath}$ - there are new fluctuation and dissipation processes at play. One can attempt a computational scheme that incorporates coupling of electrons to a
laser pump, the coupling of system
phonons to a thermal bath, and the Holstein interaction that couples electrons and
phonons. We attempt an approximation where the pump induced electronic excitations are modeled by a slowly time varying `electron temperature', $T_{\rm el}(t)$, indicative of a quasi-
equilibrium electronic state. We solve the problem for different combinations of $T_{\rm el}$ and $T_{\rm bath}$, probing the order parameter dynamics, the static properties and excitations in the long time `quasi steady state', and establish a `phase diagram' in terms of bath temperature and electron temperature.
Read the full abstract ▾
Quantum Physics
Anomalous weak values in a generalized Mach-Zehnder interferometer extracted directly from intensity measurements
Ismaele V. Masiello, Hartmut Lemmel, Andreas Dvorak et al. (+2 more)
Weak values provide a powerful framework for characterizing
quantum systems. Their experimental extraction conventionally relies on weak conditioned von Neumann measurements, involving weak interactions and meter states that increase experimental complexity and often limit measurement efficiency. Here we introduce a method to fully characterize path weak-values in a generalized Mach-Zehnder interferometer employing neither meter states nor weak interactions. We experimentally demonstrate the technique in matter-wave interferometry. We identify anomalous weak values and, equivalently, negative quasiprobability distributions, which reflect the nonclassical behavior of the
quantum system. The approach relies uniquely on intensity measurements at the output ports of the interferometer combined with controlled relative phase shifts between the paths. The absence of meter states enables considerable simplification of the setup and shorter measurement times, while preserving full access to weak values with comparable or increased accuracy. The scheme is directly applicable to a broad class of experiments involving two-level
quantum systems.
Read the full abstract ▾
All authors Ismaele V. Masiello, Hartmut Lemmel, Andreas Dvorak, Stephan Sponar, Yuji Hasegawa
Instrumentation and Detectors
LF-MightyPix: A second HV-MAPS prototype for the {LHCb} Mighty-Tracker
Toko Hirono, Sebastian Bachmann, Lucas Dittmann et al. (+5 more)
For the future high-luminosity operation of the LHCb experiment, the downstream tracker will be upgraded to the Mighty-Tracker. A key part of this upgrade is the introduction of silicon pixel detectors, MightyPix, in the central region of the tracker. We have developed MightyPix prototype chips using High-Voltage Monolithic Active Pixel Sensors fabricated in a commercially available CMOS process on high-resistivity wafers. The second prototype chip, LF-MightyPix, is fabricated in the LFoundry 150 nm CMOS process. LF-MightyPix has a chip size of 3.5 mm $\times$ 4.0 mm and a pixel size of 0.1 mm $\times$ 0.1 mm. For each pixel hit, both the time of arrival and the time over threshold are recorded to ensure correct bunch-crossing identification at 40 MHz. The results presented in this paper confirm compatibility with the MightyPix requirements.
Read the full abstract ▾
All authors Toko Hirono, Sebastian Bachmann, Lucas Dittmann, Richard Leys, Nicolas Striebig, Celina Welschoff, Hui Zhang, Ivan Peric
Quantum Physics
Compressed Quantum Operators and Roots of Hermite Polynomials
Serge Adonsou, Guillaume Dauphinais, David W. Kribs et al. (+1 more)
The fundamental position and momentum operators of
quantum mechanics are unbounded, but finite rank compressions of the operators can be considered to obtain partial information on the operators and their properties. Motivated by problems in photonic
quantum computing, we bring together results from
quantum theory and the theory of orthogonal
polynomials to show that a natural finite rank compression of the position and momentum operator representation on Fock space
Hilbert space has
eigenvalues given by roots of the classical Hermite
polynomials. We discuss the corresponding compressed displacement operators and potential applications in approximate
quantum error correction.
Read the full abstract ▾
All authors Serge Adonsou, Guillaume Dauphinais, David W. Kribs, Rajesh Pereira
Quantum Physics
Faster algorithm for achieving minimal-size quantum decision diagrams
Juul Sanders, Sebastiaan Brand, Arend-Jan Quist et al. (+1 more)
The decision diagram (DD) data structure enables fast linear-
algebra calculations by bringing vectors into a normal form and subsequently merging equivalent ones, yielding a minimally-sized DD modulo the equivalence relation. A fruitful application area is
quantum-
circuit simulation, where the vectors represent
quantum states. The Local Invertible Map Decision Diagram (LIMDD) type, merges LIM-equivalent (typically Pauli-gate equivalent) vectors, can efficiently simulate Clifford
circuits as well as some high-T-count
circuits, and has theoretically been proven exponentially faster for simulation than other well-developed data structures, including other common DD variants. However, these exponential advantages have not fully materialized yet in existing implementations, for which the normal-form procedure, which is a highly complex
algorithm, is either absent or only partially implemented. We here present a novel normal-form
algorithm for Pauli-LIMDDs, achieving a worst-case speedup from $O(n^3)$ to $O(n^2)$ for an $n$-
qubit DD node with a single child node while keeping the $O(n^3)$ run time in case of two distinct children nodes. We implement the
algorithm as part of QolDDer, our Pauli-LIMDD simulator for
quantum circuits, written from scratch in C/C++. The implementation realizes the theoretically-proven advantages of Pauli-LIMDDs on Clifford
circuits, is significantly faster than the existing LIMDD simulators on such
circuits, and on a public
quantum-
circuit data set often outperforms them by an order of magnitude. In the future, we envision that our work will enable further application and development of LIMDD variants, not only for
quantum design tasks, but also for analysis of linear-
algebra-based systems in general.
Read the full abstract ▾
All authors Juul Sanders, Sebastiaan Brand, Arend-Jan Quist, Tim Coopmans
Classical Physics · Cross-listed from math.AP
A new perspective in linear Cauchy Elasticity: variational minimum principles for statics, dynamics, and heterogeneous materials
Amit Acharya
A variational minimum principle for linear elastodynamics of a possibly heterogeneous material without a stored energy function is developed. It involves a change of variables to dual fields, and results in a degenerate
elliptic Euler-Lagrange system, even when the primal elastodynamics is
hyperbolic. Uniqueness assertions for the dual dynamic and static problems and implications of the degenerate ellipticity are sketched. Some implications pertaining to heterogeneous materials and ones with indefinite elastic
moduli are discussed.
Read the full abstract ▾
Nuclear Theory
Mass-Dependent Non-Extensivity in Tsallis Blast-Wave Fits to Identified Hadron $p_T$ Spectra at RHIC and LHC
C.Y. Tsang and Z. Xu
We analyze identified-
hadron transverse-momentum spectra from
STAR Au+Au and ALICE Pb+Pb collisions over $\sqrt{s_{NN}} = 7.7$~GeV–$5.02$~TeV using an extended Tsallis Blast-Wave (TBW) framework, which includes a non-extensivity parameter $q$ to quantify the degree of incomplete thermal
equilibrium. Conventionally, either a common value of $q$, or two separate $q$ values, one for
mesons and one for
baryons, are used to describe particle spectra in the TBW framework, with the latter being referred to as TBW4 in Ref.~\cite{Chen:2020zuw}. This work extends the TBW framework by studying the dependence of $q$ on different kinds of particles in detail. Fits allowing independent non-extensivity parameters $q$ for each species reveal a systematic correlation between $q$ and particle mass, except for quarkonia. Motivated by this trend, we introduce two new parameterizations: TBW5, which posits that $q$ depends linearly on particle mass, and TBW6, which allows the $q$ intercepts for
mesons and
baryons to differ. Across all energies and centralities considered in this study, TBW5 improves $\chi^{2}/\mathrm{NDF}$ relative to the TBW4 fit in 74% of the
datasets, while TBW6 shows improvement in 93% of the
datasets. They perform especially well in central collisions. These results demonstrate a robust mass ordering in non-
equilibrium behavior at kinetic freeze-out and provide a more accurate description of
hadron spectra from RHIC to LHC energies.
Read the full abstract ▾
Quantum Physics
A high-fidelity two-qubit gate for multimode superconducting P-mon qubits
Frederik Pfeiffer, Federico A. Roy, Niklas J. Glaser et al. (+11 more)
To scale superconducting
quantum processors, it is essential to achieve long coherence times while engineering interactions that do not introduce additional decoherence channels. In superconducting
qubit systems, this can be realized using multimode
circuits that feature a protected
qubit mode alongside a distinct mediator mode. Building on this concept, our recently developed P-mon
qubit provides intrinsic protection against decoherence from the readout environment. We extend this approach to controlled two-
qubit interactions, by exploiting the mediator modes of P-mons for on-demand coupling. Because direct interactions between the
qubit modes are strongly suppressed, unwanted $ZZ$-type interactions are significantly reduced to below $3.6(5)~\text{kHz}$ in the idle state. When tuning the coupled mediator modes on resonance, the cross-Kerr interaction between the
qubit and the hybridized mediator modes leads to a
qubit-state dependent frequency shift. By selectively addressing these transitions, we implement a $180~\text{ns}$ long CZ gate and determine a fidelity of $99.62(4)~\text{%}$. These results represent a significant step toward a scalable superconducting architecture that maintains high performance at scale.
Read the full abstract ▾
All authors Frederik Pfeiffer, Federico A. Roy, Niklas J. Glaser, Julius Feigl, Leon Koch, Kevin Kiener, Gleb Krylov, Johannes Schirk, Christian M. F. Schneider, Lasse Södergren, Florian Wallner, Max Werninghaus, Carlos A. Riofrío, Stefan Filipp
Atomic Physics
Two-Electron Effects Extend High-Harmonic Generation into the keV Regime
Isobel McSweeney, Andres Marchisio, Javier Rivera-Dean et al. (+4 more)
Two-electron processes can generate high harmonics beyond the conventional single-active-electron cutoff. Motivated by recent experimental evidence of an extended secondary plateau in the helium high-harmonic spectrum [S. Wang et al, Optica, (2023); S. Wang et al, In Print in Nature
Photon., (2026)], we present a two-electron generalisation of the strong-field approximation. We analyse the resulting expressions using the saddle-point method and determine the extended cutoff. We find good agreement with classical predictions of cutoff scalings of $4.7$ and $5.5$ times the ponderomotive energy, which significantly exceed the established single-electron scaling of 3.17. We calculate high-harmonic spectra generated via a two-electron process in helium atoms driven by an intense few-cycle infrared
laser pulse. Our results demonstrate that the harmonic spectrum extends far beyond the water window, reaching
photon energies up to $\approx 1.2\,\mathrm{keV}$ in the soft x-ray region. The large spectral bandwidth can support the generation of sub-attosecond soft x-ray pulses, which are of particular interest for probing ultrafast dynamics across matter, including applications in core-level spectroscopy and biological imaging.
Read the full abstract ▾
All authors Isobel McSweeney, Andres Marchisio, Javier Rivera-Dean, Philipp Stammer, Paraskevas Tzallas, Marcelo F. Ciappina, Maciej Lewenstein
High Energy Physics (Phenomenology)
Radiative decays of dynamically generated pentaquarks in the chiral unitary approach: the $P_c(4457)\to P_c(4312)\,\gamma$ transition
Ratirat Suntharawirat, Nongnaphat Ponkhuha and Daris Samart
We study the radiative decay of dynamically generated pentaquarks and apply the formalism to the transition $P_c(4457)(3/2^-)\to P_c(4312)(1/2^-)\gamma$. Both states are treated as $S$-wave hadronic molecules generated in the
chiral unitary approach with heavy-
quark spin symmetry and the local hidden gauge interaction. The
photon therefore couples to the
meson-
baryon components of the two poles. The calculation combines the strong coupling residues of the coupled-channel solution, heavy-
quark spin symmetry for the electromagnetic vertices, and a transverse assembly of the $M1$ triangle loops. A complete calculation gives nineteen triangle loops. We reduce each loop to a single numerical quadrature and give the closed analytic form. The electromagnetic vertices that are not fixed by data are estimated with the naive-
quark model and heavy-
quark spin symmetry. We normalize the main $D^*D\gamma$ coupling to $\bar D^{*0}\to\bar D^{0}\gamma$ and test the same convention with $J/\psi\to\eta_c\gamma$. The central width is $6.7\keV$, with a conservative range of about $2$ to $9\keV$. This radiative decay process is a pure $M1$ transition with
photon energy $143\MeV$. The $\bar D^{*0}\to\bar D^{0}\gamma$ loop gives the leading contribution. The near-threshold $\bar D^{*}\Lambda_c$ loop gives the main correction. A soft Gaussian form-factor on the leading diagram reduces the width to about $2\keV$, compatible with earlier molecular results, and decreases the full width to about $4\keV$. The coherent result is sensitive to the relative residue phases in the coupled-channel convention. We also estimate the cascade rate for $\Lambda_b^{0}\to J/\psi\,p\,K^{-}\gamma$ and discuss how the line can be searched for. The pure $M1$ content, the ratio to the $P_c(4440)$ radiative decay, and the binding-energy dependence of the width are proposed as tests of the molecular nature.
Read the full abstract ▾
Astrophysics of Galaxies
Galactic Hubs: New Insights and SKA View of AGN Feedback in Galaxy Groups
T. Pasini, M. Brienza and C. J. Riseley
Over the last two decades, significant effort has been devoted to understand the physical processes involved in
galaxy evolution. In this context, AGN feedback has emerged as the leading explanation for several longstanding astrophysical questions, including the origin of scaling relations between supermassive black holes and their host
galaxies.
Galaxy clusters have been particularly put under the lens, thanks to the combination of high-resolution X-ray and
radio observations which allowed to investigate the link between thermal and non-thermal emission. On the other hand, research in the lower-mass regime of
galaxy groups remains limited. This is mostly due to observational limitations in the high-energy regime, which prevents the study of the non-thermal emission in the context of its surrounding environment. Nevertheless, this is a key topic for
galaxy evolution, as the vast majority of
radio-loud AGN in the nearby Universe are hosted in
galaxy groups. Recently, modern
radio facilities such as LOFAR, uGMRT and MeerKAT have obtained interesting results in this regime. Examples include signatures of overheating caused by AGN, groups with largely evacuated environments due to powerful and prolonged feedback activity, and remnant
plasma displaced by large-scale sloshing motions. This chapter reviews these advances while identifying gaps in our understanding. We will explore how SKA promises to close these gaps and revolutionise the field through its unparalleled combination of high resolution and sensitivity across a wide frequency range. Moreover, its unique capabilities, in synergy with state-of-the-art and upcoming surveys carried out by new instruments, will facilitate the construction of unprecedentedly large samples of groups, dramatically enhancing the statistical power of future studies.
Read the full abstract ▾
General Relativity and Quantum Cosmology · Cross-listed from math.DG
On Chen-Teo geometries with cosmological constant
Bernardo Araneda
The Chen-Teo geometry is a Riemannian,
Ricci-flat ALF 4-
manifold, containing an AF gravitational instanton that gives the first counterexample to the Euclidean black hole uniqueness
conjecture. We investigate the problem of constructing an Einstein analogue with a non-zero cosmological constant $\lambda$. We show that the solution is either the Plebański-Demiański metric with $\lambda$, or it has an anti-self-dual Weyl tensor. We study the latter case in detail: we prove that for $\lambda<0$, there is a conformal infinity separating two asymptotically
hyperbolic metrics; we show that one of them is globally conformal to an ALE scalar-flat Kähler metric; we construct gravitational instantons with different
topologies; and we show that the geometry is a 4-pole solution in the Calderbank-Pedersen classification.
Read the full abstract ▾
Geophysics
Offset-continuation-trajectory stacking based on common-reflection-point kinematics for five-dimensional prestack dataset regularization and enhancement
Tiago A. Coimbra, Rodrigo Bloot, Caian Benedicto et al. (+2 more)
Prestack seismic data regularization and enhancement are critical steps for reliable imaging and inversion, particularly in five-dimensional (5D)
dataset geometries affected by irregular sampling, noise contamination, and incomplete spatial coverage. These limitations often degrade event continuity and compromise the physical consistency of conventional interpolation methods. This study introduces a physics-informed framework for 5D prestack
dataset reconstruction based on a multi-parameter common-reflection-point (CRP) traveltime stacking operator. The proposed offset-continuation-trajectory (OCT) operator derives coherent stacking trajectories from wavefront propagation, isochronous surface geometry, specular reflection, and diffraction kinematics. All kinematic parameters are estimated directly from the data through a global coevolutionary optimization strategy. The method reconstructs missing traces and enhances spatial continuity by stacking seismic events along physically consistent traveltime surfaces, preserving both reflection and diffraction kinematics. Applications to synthetic and field
datasets demonstrate improved signal-to-noise ratio, enhanced structural continuity, and reliable recovery of unrecorded amplitudes without introducing artificial events. The results indicate that incorporating physically constrained traveltime models into the regularization process provides a robust, geologically consistent alternative to purely mathematical interpolation techniques, thereby improving data fidelity for subsequent imaging and quantitative interpretation.
Read the full abstract ▾
All authors Tiago A. Coimbra, Rodrigo Bloot, Caian Benedicto, Nicholas T. Okita, Jorge H. Faccipieri Junior
Earth and Planetary Astrophysics
Coupled atmospHere Interior modeL Intercomparison (CHILI). I. Evolutionary Modelling – Primordial Magma Oceans of Earth and Venus
Harrison Nicholls, Joshua Krissansen-Totton, Tim Lichtenberg et al. (+22 more)
Earth and Venus represent two evolutionary outcomes arising from initially molten 'magma ocean' periods, followed by lifetimes of chemical and geophysical divergence. Their physics is common to all rocky
planets and is accessible to simulations that adopt coupled interior-atmosphere modelling approaches. Our understanding of
planet histories and interpretation of current states is dependent on this modelling, yet existing codes vary in their approximations. Here, we present the first results from the Coupled atmospHere Interior modeL Intercomparison (CHILI) project; benchmarking planetary
evolution codes in the context of Earth and Venus to identify key model sensitivities. Our 'nominal' Earth models predict magma ocean solidification timescales within 4 Myr of thermal
evolution, and are consistent with empirical constraints on Earth's early history. Venus scenarios exhibit more diverse behaviours where prolonged magma ocean stages can be conditionally sustained for 50 Myr. Cooling timescales correlate with initial hydrogen and carbon budgets, but model-specific treatments of volatile partitioning and vertical energy transport introduce substantial inter-model variance. Different parametrisations of mantle geodynamics, convection, melting curves, rheological properties, and radiative transfer give rise to divergent evolutionary behaviours. Discrepancies in atmospheres generated by magma ocean outgassing underscore these differences, although C-H-O compositions with surface pressures exceeding 100 bar are favoured. This intercomparison identifies critical sensitivities in volatile partitioning, escape processes, mantle viscosity, and melting. Validating these treatments is essential for enabling deep insight into the early histories of the
Solar System's terrestrial
planets, and for drawing meaningful interpretations from ongoing observational
exoplanet campaigns.
Read the full abstract ▾
All authors Harrison Nicholls, Joshua Krissansen-Totton, Tim Lichtenberg, Laura Schaefer, Keiko Hamano, Maxime Maurice, Henri Samuel, Alexandra Papesh, Carlos Ortiz-Quintana, Junellie Perez, Yamila Miguel, Denis Sergeev, Philipp Baumeister, Spanan Dash, Leoni Janssen, Jonathan Keathley, Alexandre de Larminat, Emmanuel Marcq, Lena Noack, Hugo Pelissard, Bo Peng, Emma Postolec, Ramses Ramirez, Mariana Sastre, Andrea Zorzi
Strongly Correlated Electrons
On Degeneracies of Density, Magnetic, and Pairing Responses: How Competing Orders Echo Underlying Symmetries in the Hubbard Model
Michael Meixner, Herbert Eßl, Matthias Reitner et al. (+2 more)
Strongly correlated electron systems often display competing or even intertwined ordering tendencies, hinting to extremely close or degenerate many-electron energies. While degeneracies are directly rooted in the underlying
symmetries of the problem under investigation, their multifaceted effects on different response functions and their mutual relations often remain elusive. Here we put this subject on a rigorous basis by investigating the degeneracies of charge,
spin, and pairing susceptibilities for the unfrustrated, bipartite Hubbard model. Exploiting its pseudospin
symmetry, we analytically derive the mutual relations between these response functions for generic spatial modulations, highly relevant, e.g., for the competition of stripe and superconducting orders. By means of two-particle numerical simulations we demonstrate the occurrence of a simultaneous $d$-wave pairing/$d$-density wave (loop current) instability in the vicinity of the metal-
insulator transition, driven by short-ranged
spin fluctuations for the two-dimensional case. We show how this degeneracy is gradually lifted by geometrical frustration, which favors superconductivity. Our study provides a general tool for revealing
symmetry relations in correlated electron systems and establishes a unifying perspective on the nature of their intermingled charge/loop current, pairing, and
spin orders.
Read the full abstract ▾
All authors Michael Meixner, Herbert Eßl, Matthias Reitner, Alessandro Toschi, Thomas Schäfer
Applied Physics
Material identification using laboratory X-ray beam tracking: quantitativeness and signal-to-noise ratio requirements
Sumera Rehman, Ashkan Ajeer, Connor Darling et al. (+3 more)
Simultaneous structural and elemental characterisation of a specimen in a non-destructive manner is an instrumental approach with applications in a variety of fields including energy materials, cultural heritage and life sciences. This is routinely performed at synchrotron facilities, e.g. by combining X-ray imaging and X-ray fluorescence. In this work we describe an approach based on a monochromatic implementation of X-ray beam tracking (XBT), a
multimodal imaging technique compatible with standard laboratory sources. Monochromatic XBT gives simultaneous access to quantitative absorption and phase properties of the sample, which are related to the atomic number and the electron density respectively: their combination allows for material discrimination. Here we focus on investigating the effect of the signal-to noise ratio on the quantitativeness of the results, hence on the elemental identification. We present an XBT experiment performed using a standard X-ray laboratory source to identify the composition of three different test samples made out of Ag, Fe and Cu. These specific materials were selected as relevant to archaeological studies e.g. when specimen buried for centuries are in contact with the surrounding soil containing traces of these metals. We review the results, current limitations and provide guidance for future developments for structural and elemental characterisation in a laboratory setting.
Read the full abstract ▾
All authors Sumera Rehman, Ashkan Ajeer, Connor Darling, Marco Endrizzi, Alessandro Olivo, Silvia Cipiccia
Chemical Physics
Quantum nuclear and band-dispersion effects recover near-UV absorption in short-hydrogen-bonded organic crystals
Jonas Hänseroth, Max Großmann, Malte Grunert et al. (+4 more)
Near-UV optical absorption is increasingly reported in hydrogen-bonded organic and biomolecular materials lacking aromatic or extended pi-conjugated chromophores, yet its microscopic origin remains unresolved and electronic-structure calculations often overestimate experimental absorption onsets. Here, we combine machine-learned interatomic potentials for large-scale classical and
quantum nuclear sampling with periodic excited-state calculations to address this discrepancy in L-pyroglutamine ammonium, an experimentally established glutamine-derived
crystal containing a well-resolved short hydrogen bond and exhibiting non-aromatic near-UV optical response. Using controlled in silico ion substitutions that vary the surrounding hydrogen-bond environment while preserving this scaffold, we compute optical spectra from configurations sampled along classical and
quantum nuclear trajectories using hybrid-functional time-dependent density functional theory. We show that
nuclear quantum effects stabilise
proton-sharing configurations that are strongly suppressed classically, redshifting the lowest bright excitations by 0.5-0.8 eV and raising the fraction of configurations with bright excitations below 6 eV from approximately 3% to approximately 30%. Explicit Brillouin-zone sampling provides a further, mechanistically distinct
redshift of 0.5-1.1 eV, reflecting modest but significant indirect electronic character. Only when both effects are incorporated does the calculated onset recover the experimental 3.8-4.5 eV range. These results establish
quantum proton fluctuations and reciprocal-space convergence as cooperative but physically distinct ingredients required for predictive optical spectroscopy of strongly hydrogen-bonded molecular materials.
Read the full abstract ▾
All authors Jonas Hänseroth, Max Großmann, Malte Grunert, Ali Hassanali, Erich Runge, Christian Dreßler, Muhammad Nawaz Qaisrani
Quantum Physics
Asymptotic Compression of Interactive Quantum Communication using Type-Constrained de Finetti Reduction
Louis Desruisseaux, Simon Ducharme, Gurleen Padda et al. (+1 more)
For many information processing tasks, de Finetti-style
theorems can often simplify the analysis in worst-case input scenarios for which the task exhibits some permutation-invariance
symmetry, as they can allow for a reduction from an analysis on worst-case inputs to that of i.i.d. inputs. If further information is available on the inputs, it might be advantageous to reflect this information in the de Finetti reduction. In our work, we focus on a form of such constraint, based on the type of the input. This allows us to obtain a conceptually simple proof of a new de Finetti reduction for classical probability distributions, derived from elementary properties from the method of types. We apply our constrained de Finetti reduction to the compression of
quantum interactive communication protocols with classical inputs, and prove that the prior-free
quantum information cost equals the worst-case input amortized
quantum communication cost.
Read the full abstract ▾
All authors Louis Desruisseaux, Simon Ducharme, Gurleen Padda, Dave Touchette
Astrophysics of Galaxies
Unlocking the Full Potential of SKAO Extra-galactic Science with High-multiplex Optical Spectroscopy
Kenneth J Duncan, Natasha Maddox, Daniel J. B Smith et al. (+9 more)
Parallel to the transformation in
radio continuum and H I observations from SKAO pathfinders and precursors over the past decade has been the development of a new generation of multi-object spectrographs that will be equally transformational in a broad range of scientific areas. For all extragalactic
radio source populations, this spectroscopy is essential for providing precise
redshifts, separating
star-formation and AGN activity, identifying
accretion modes and revealing detailed host
galaxy properties. It is only with the detailed emission line and optical continuum diagnostics from spectroscopy that we can begin to link the AGN and
star-formation activity revealed by the
radio continuum to the kinematic and chemical histories of
galaxies. Crucially, extensive spectroscopy also unlocks the full potential of H I observations by enabling statistical measures of the H I content of
galaxies out to $z = 1$ and beyond, through spectral stacking analyses, as well as comprehensively tracing the local environment and large-scale structure to enable studies of environmental effects on the
baryon cycle. We outline the scientific synergies enabled by combining SKAO continuum and H I surveys with current optical spectroscopic surveys, as well as identifying the needs and scientific potential of future spectroscopic surveys dedicated to the
radio source population with both existing and planned optical facilities.
Read the full abstract ▾
All authors Kenneth J Duncan, Natasha Maddox, Daniel J. B Smith, Marina I Arnaudova, Catherine L Hale, Sophia Flury, Luke Holden, Matt J Jarvis, Elizabeth A. K. Adams, S. Ilani Loubser, Mamta Pandey-Pommier, Anastasia Ponomareva
Earth and Planetary Astrophysics
Stellar Wind Driven Alfvén Wing Dynamics in Planetary and Exoplanetary Magnetospheres
Sakshi Gupta, Arnab Basak and Dibyendu Nandy
Magnetized obstacles embedded within a
plasma flow generate magnetohydrodynamic structures known as Alfvén wings, which act as primary conduits for the transfer of momentum and energy between the body and the surrounding medium. This study employs three-dimensional resistive magnetohydrodynamic simulations to explore how these wings and the magnetosphere respond to diverse
stellar wind conditions. Our results, gleaned from a large number of systematic simulations spanning a wide range of
stellar wind speed and
magnetic field – and planetary dipole field – show that the global magnetospheric configuration is highly sensitive to the upstream Alfvén Mach number. We find that increasing
stellar wind speed leads to a systematic closure and narrowing of Alfvén wing structures, while stronger
stellar magnetic fields facilitate their opening. Analysis of the Alfvén wing morphology demonstrates a distinct dependence of wing opening angle on
stellar wind speed, with internal wing analysis showing a reduction in
plasma velocity and significant
magnetic-flux accumulation. Our results exhibit a clear interdependence between the day-side magnetopause stand-off distance and the night-side magnetotail current sheet length. We find a linear scaling between the magnetotail dynamics and upstream forcing parameters. This study bridges the gap between
solar system observations and (exo)planetary systems by demonstrating how Earth-like magnetospheres might transform into wing-dominated configurations during extreme
stellar events or within the sub-Alfvénic regimes of close-in (exo)
planets. Our findings can aid the interpretation of Alfvén wing signatures in observational data and enhance our understanding of how (exo)planetary magnetospheres respond to dynamic
stellar wind forcing.
Read the full abstract ▾
High Energy Astrophysical Phenomena
Probing Merger Shocks in Galaxy Clusters in the SKA Era
Arpan Pal, Ruta Kale, Gabriella Di Gennaro et al. (+8 more)
Galaxy cluster mergers represent the most energetic phenomena in the Universe since the Big Bang releasing gravitational potential energy of $\sim 10^{63-64}$ erg, injecting
turbulence and driving shocks through the intracluster medium (ICM). These merger shocks can accelerate
cosmic ray electrons and compress
magnetic fields, sometimes producing Mpc-scale synchrotron
radio structures known as
radio relics.
Radio relics are powerful tracers of merger dynamics, particle acceleration, and
magnetic field
evolution, yet fundamental questions about the underlying physics and their time
evolution remain unresolved. In this chapter, we review the current understanding of cluster merger shocks and their
radio signatures, presenting the observational evidence from the SKA pathfinders and precursors, linking
radio relics to shocks alongside outstanding theoretical challenges. We also consider related shock-influenced phenomena:
radio phoenices from revived fossil AGN
plasma and Gently Re-Energised Tails. Further, we outline the directions of investigation using the sensitivities of the SKA-Low and Mid complemented with X-ray observations that will allow us to make significant progress in understanding the cluster merger shocks. Detailed studies of individual targets in continuum and polarization and studies of populations of relics using wide surveys will both provide insights to the micro-physics and
cosmic evolution of merger shocks. We present SKAO capabilities across staged deployments starting from AA0.5 to AA4 and identify science verification targets that will illuminate the physics of cluster merger shocks in the SKA era
Read the full abstract ▾
All authors Arpan Pal, Ruta Kale, Gabriella Di Gennaro, Francesco de Gasperin, Swarna Chatterjee, Majidul Rahaman, Ramananda Santra, Mamta Pandey-Pommier, Abhirup Datta, Kenda Knowles, Nasmi S. Anand
Quantum Physics
No linear stretching of single-copy quantum pseudorandomness
Boyang Chen, Andrea Coladangelo, Yao-Ting Lin et al. (+3 more)
Pseudorandom states, introduced by Ji, Liu, and Song (CRYPTO 2018), are
quantum analogues of classical pseudorandom generators. A fundamental property of classical pseudorandom generators is that their output can be stretched to arbitrary
polynomial length. Whether an analogous stretching property holds for
quantum pseudorandom states has been elusive. Here, we essentially resolve this question for the single-copy variant of pseudorandom states, 1PRS. We show, via a
unitary oracle separation, that no fully black-box construction can stretch the output length of a 1PRS by any constant factor greater than one.
Read the full abstract ▾
All authors Boyang Chen, Andrea Coladangelo, Yao-Ting Lin, Nikos Skoumios, Justin Tysdal, Yiming Wang
Astrophysics of Galaxies
The dependence of Circumgalactic Medium properties on halo assembly histories in the IllustrisTNG simulations
Yiyuan Zhang, Houzun Chen and Xi Kang
While
halo mass is the dominant factor shaping the embedded
galaxies, the properties of the circumgalactic medium (CGM) also depend on
halo assembly history. To investigate this, we calculate the formation times for TNG50
halos with masses between $10^{10.5}$ and $10^{12.5} M_\odot$, classifying them into `early-' and `late-forming' populations. It is found that across all mass bins, early-formed
halos generally host
galaxies with higher
stellar mass and higher
metallicity, with lower CGM gas mass and lower specific
star formation rate (sSFR) at $z\sim0$. For the CGM
metallicity, `early'
halos with masses below $10^{12}\mathrm{M_\odot}$ show systematically higher gas phase
metallicities, whereas in the $10^{12-12.5}\mathrm{M_\odot}$ bin the trend reverses. When examining the origins of the CGM gas, it is found that fresh
accretion is insensitive to assembly history, whereas the `late'
galaxies experience more wet mergers. These differences in gas properties arise from processes after the formation time, given that the CGM gas masses show no significant differences at formation time. Finally, our analysis of CGM kinematics shows that for
halos below $10^{12}\mathrm{M_\odot}$, the cold gas in late-forming
halos carries higher specific angular momentum and simply has a higher degree of rotational support, while the same properties in the $10^{12-12.5}\mathrm{M_\odot}$ bin shows no significant dependence on assembly history.
Read the full abstract ▾
Cosmology and Nongalactic Astrophysics
Interferometric HI Intensity Mapping of the Late Time Universe with SKA-Mid
Aishrila Mazumder, Zhaoting Chen, Junaid Townsend et al. (+6 more)
We discuss the progress towards using the SKA-Mid for interferometric neutral hydrogen (HI) intensity mapping surveys. By mapping the distribution of
cosmic HI distribution through the 21cm line, SKA-Mid will be able to measure the HI power spectrum at small angular separations in interferometric mode. We review the measurements made from the precursor MeerKAT
telescope, using the MeerKAT DEEP2 as well as the MIGHTEE survey data, yielding tentative detection as well as upper limits on HI clustering. The methodology for MeerKAT can be naturally extended to SKA-Mid. Forecasts suggest that SKA-Mid AA4 will be able to measure the HI power spectrum with high statistical significance across a wide range of
redshifts from $z\sim1.0$ to $z\sim 3.0$, around nonlinear scales $k\sim 1.0\,{\rm Mpc}^{-1}$. The precise measurements can be used to constrain the properties of HI
galaxies, providing a novel window into probing
galaxy evolution at $1.0\lesssim z \lesssim 3.0$.
Read the full abstract ▾
All authors Aishrila Mazumder, Zhaoting Chen, Junaid Townsend, Suman Chatterjee, Zhixing Li, Sourabh Paul, Reza Ansari, Laura Wolz, Mario G. Santos
Instrumentation and Detectors
A Reproducible Benchmark and Evidence-Retrieval Software Framework for Silicon Detector R&D Literature
Tianqi Gao, Ruobing Jiang, Dawei Fu et al. (+2 more)
Silicon pixel detector R&D depends on a large and rapidly growing technical literature, including beam-test and irradiation studies, performance measurements, simulation, and design reports. Locating the supporting evidence passage for a measurement, operating condition, or design decision is therefore a computing and data-science challenge for detector-development workflows. General-purpose
language models are insufficient unless grounded in traceable primary sources, particularly in a domain with specialised terminology, configuration-dependent measurements, and rapidly evolving experimental results. We address this with a reproducible, general-purpose framework for evidence-grounded
retrieval over technical literature, using silicon pixel detector R&D as a demanding validation domain. The framework combines sparse lexical
retrieval, dense semantic
retrieval, and hybrid reciprocal-rank fusion, with an optional graph-guided exploration layer and grounded, abstention-aware response generation. The accompanying
benchmark provides manually curated chunk-level evidence annotations, source-level diagnostics, semantic relevance checks, and negative-query abstention tests over two detector query sets. We evaluate six
retrieval configurations across 378 source documents and 8,442 indexed chunks. Hybrid sparse-dense
retrieval gives the strongest strict evidence recovery, achieving Hit@5 of 0.917 on the core
benchmark and 0.951 on the curated extension
benchmark, while graph-based methods are more effective for literature exploration and source discovery. Graph expansion is therefore best employed as a discovery layer over the hybrid
retrieval backbone. The framework provides reusable software for traceable, 1 evidence-grounded knowledge access in silicon detector R&D and high-energy physics instrumentation.
Read the full abstract ▾
All authors Tianqi Gao, Ruobing Jiang, Dawei Fu, Qiang Li, Matthew Kenzie
Cosmology and Nongalactic Astrophysics
Imaging the 21-cm Signal from the Cosmic Dawn & Epoch of Reionization and the Connection with the Global Signal
Satadru Bag, Michele Bianco, Samir Choudhuri et al. (+12 more)
The original baseline design for SKA-Low was motivated by the ability to produce tomographic images of the redshifted 21-cm signal, thus allowing the research field to move beyond the simple statistic of the power spectrum. In this chapter we review the imaging capabilities of SKA-Low, the wide variety of methods proposed for quantatively analysing image data, as well as the connection with the global 21-cm signal.
Read the full abstract ▾
All authors Satadru Bag, Michele Bianco, Samir Choudhuri, Saswata Dasgupta, Abhirup Datta, Kanan K. Datta, Ivelin Georgiev, Sambit K. Giri, Ian Hothi, Akanksha Kapahtia, Suman Majumdar, Garrelt Mellema, Arnab Mishra, Samit Kumar Pal, Feiyu Zhao
Quantum Physics
Rotational Vacuum Friction of Nonabsorbing Particles
F. Javier García de Abajo and Alejandro Manjavacas
A nonabsorbing particle rotating in
vacuum can lose angular momentum only by converting mechanical energy into electromagnetic radiation. Here, we develop a
quantum theory of rotational
vacuum friction for small lossless particles and show that axial
symmetry qualitatively changes the leading dissipation channel. At zero temperature, the frictional torque scales as $M\propto\Omega^7$ with rotation frequency $\ Omega$ in anisotropic particles due to the emission of correlated
photon pairs whose frequencies sum to $2\Omega$, while a contribution to the torque linear in $\ Omega$ is found at finite temperature. In contrast, axisymmetric particles are protected against
photon-assisted friction regardless of temperature.
Read the full abstract ▾
Disordered Systems and Neural Networks
On the localization transition from MAA to AA models
Hangdong Qiu and Yunhua Wang
Despite their potential similarity between the mosaic Aubry-André (MAA) and AA models, the MAA model allows mobility edges (MEs), whereas the AA model does not. Here we develop a new double quasiperiodic MAA (DMAA) model consisting of one primitive MAA with nonzero even-site potentials and the other modified one with both nonzero odd-site potentials and a tunable amplitude factor, to reveal how localization transitions evolve from MAA to AA models. Interplays and competitions among the extended, critical and localized states arising from superpositions of double quasi-periodic MAA potentials enable new twice and multiple localization-delocalization transitions besides the original single localization transition. Our numerical calculations on inverse participation ratio, normalized participation ratio, fractal dimension and real-space wavefunction distribution confirm such localization features. The continuum model simulations on the experimental polariton modes also yield consistent results and hence validate their experimental feasibility. The constructed DMAA model provides a new framework for studying the localization transition processes between two analogous quasiperiodic models and broadens the understanding of Anderson localization.
Read the full abstract ▾
High Energy Physics (Theory)
Symmetric mass generation of interacting chiral fermions on a one-dimensional lattice without fermion doubling
V. A. Zakharov, Atsushi Ueda, Frank Verstraete et al. (+1 more)
Symmetric mass generation is the interaction-induced opening of a
fermion gap without spontaneous
symmetry breaking. The anomaly-free 3-4-5-0 model of Wang and Wen provides a minimal one-dimensional setting for this phenomenon, but a direct
lattice realization faces two obstacles:
fermion doubling for local
chiral discretizations and perturbative irrelevance of the six-
fermion gapping interaction. We address both obstacles. First, we formulate the model on a strictly one-dimensional tangent-
fermion lattice, where a nonlocal hopping produces a single
chiral branch without a mirror partner while retaining an efficient tensor-network representation. Second, we add a Hubbard-type density-density interaction (Luttinger parameter $K$) that reduces the scaling dimension of the 3-4-5-0 interaction from $5$ to $5K$, making it relevant for $K<2/5$. Density-
matrix renormalization group calculations show the opening of an excitation gap in this regime without the appearance of a degenerate ground state, the hallmark of symmetric mass generation.
Read the full abstract ▾
All authors V. A. Zakharov, Atsushi Ueda, Frank Verstraete, C. W. J. Beenakker