Astrophysics of Galaxies
Wrinkles in Time. II. Stellar Age Trends in Kinematic Signatures from Transient Spiral Structure
Amy Smock, Kathryne J. Daniel, Rayna Rampalli et al. (+4 more)
Spiral arms in the disks of
galaxies like the Milky Way can generate kinematic signatures, which appear as ridges or wrinkles in action space. Such signatures have proven difficult to disentangle using kinematic measures alone. In this study, we investigate how including
stellar age as an additional dimension for analysis may provide a novel insight into the physical characteristics, timescales, and nature of the progenitors of such perturbations, where these novel insights could contribute to our understanding of the history of spiral arms in the Milky Way. We used a suite of tracer particle simulations that modeled a variety of prescriptions for spiral arms to characterize observable trends. The Lindblad resonances of nonwinding spirals produce signature overdensities, or wrinkles, in a kinematic space that is typically associated with older
stellar populations (high radial action). We find that these wrinkles are preferentially populated with
stars that were initially in nearly circular orbits, kinematics that is generally correlated with younger
stellar ages. It follows that the
stellar age distribution of wrinkle populations could serve to place constraints on the past passage of a transient spiral pattern in the
solar neighborhood. For example, our simulations suggest that a physically motivated spiral pattern could significantly populate a wrinkle with zero-age
stars in orbits typically occupied by
stars much older than the Sun.
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All authors Amy Smock, Kathryne J. Daniel, Rayna Rampalli, Elisabeth R. Newton, Olivia McAuley, Sóley Hyman, Lipika Chatur
Quantum Physics
Schrödinger and Heisenberg non-Markovianity in quantum information tasks
Federico Settimo, Kimmo Luoma, Jyrki Piilo et al. (+3 more)
Quantum non-Markovianity has been widely studied and connected to the existence of
memory effects in the dynamics of open systems. Surprisingly, working in the Schrödinger or in the Heisenberg picture can provide inequivalent description non-Markovianity: a process can appear to be memoryless in one picture, while displaying
memory effects in the other. Here, we investigate which kind of
memory is relevant for different
quantum information tasks. Some of them, such as sending information via a noisy channel, require
memory in both pictures in order to exhibit revivals in the task performance. For others, only one type of
memory is sufficient. We also provide necessary conditions for non-Markovianity in both pictures by only considering the dynamics in one picture, showing for instance that the previously considered witness of Schrödinger non-Markovianity in terms of the volume of accessible states does indeed witness non-Markovianity in both pictures at the same time.
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All authors Federico Settimo, Kimmo Luoma, Jyrki Piilo, Bassano Vacchini, Dariusz Chruściński, Andrea Smirne
Astrophysics of Galaxies
A Pixel-by-Pixel Path to Population III Discovery with JWST
Patricia Iglesias-Navarro, Thomas Harvey, Marc Huertas-Company et al. (+11 more)
The identification of the first generation of metal-free
stars, known as Population III (Pop~III), remains a primary goal of modern observational astronomy. While JWST has discovered an abundance of UV-bright
galaxies at $z > 10$, distinguishing
primordial stellar populations from early metal-enriched systems is a significant challenge. We present an end-to-end framework that combines physically motivated forward modelling from Yggdrasil
primordial models with simulation-based inference (SBI) to test Pop~III detectability in JWST-like observations, from isolated sources to realistic overlap with enriched (Pop~II) hosts. Our analysis spans several Pop~III initial mass function (IMF) assumptions, nebular configurations, and Lyman-$\alpha$ transmission scenarios, while mocking the noise properties and filter coverage of the JWST Advanced Deep Extragalactic Survey (JADES). We find that unresolved or integrated analyses are strongly limited by host-
galaxy contamination, whereas spatially resolved, pixel-based model comparison substantially improves recoverability. In our resolved experiments, detectability is highest for young and massive Pop~III clumps in nearly-quenched hosts at larger projected separations from their centres, reaching $\sim 90\%$ recovery in favourable configurations, while older and centrally embedded clumps are rarely recovered. Applying the framework to a literature candidate yields spatially differentiated behaviour: a compact blue companion is preferentially described by Pop~III-like models, while the host is better explained by fiducial Pop~I/II models. Our pipeline provides practical criteria for future searches and motivates imaging-first, spectroscopy-assisted strategies for identifying
primordial stellar populations in JWST data.
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All authors Patricia Iglesias-Navarro, Thomas Harvey, Marc Huertas-Company, Christopher C. Lovell, Johan H. Knapen, Christopher Conselice, Brant Robertson, Andrew J. Bunker, Stéphane Charlot, Natalia C. Villanueva, Hannah Übler, Zhiyuan Ji, Kevin Hainline, Christina C. Williams
Solar and Stellar Astrophysics
The forgotten bright star: Theta Eridani as a millenary stellar transient observed by Hipparchus, Ptolemy and al-Sufi
Idel Waisberg and Boaz Katz
Theta Eridani is a V=2.9
star that was nonetheless reported as one of the thirteen brightest
stars in the night sky by both Ptolemy in his Almagest (137 AD) and by al-Sufi in his The Book of Fixed
Stars (964 AD), in addition to being previously referred by Hipparchus (129 BC) as a particularly bright
star. The discrepancy between its historical and modern visual magnitude $\Delta V \sim 2.7$ is the highest among the $\sim 1000$
stars in the Almagest. Theta Eridani is actually a triple
star system, and here we combine interferometric data from VLTI/PIONIER and VLTI/
GRAVITY, spectroscopic data from ESPaDOns and FEROS, and photometric data from TESS in order to solve for the orbital parameters, masses and radii of the close inner binary Theta Eridani Aa+Ab. We find that it is a tight eccentric binary ($a=0.083 \text{ au}$, $e=0.105$) of intermediate-mass
stars ($M_{Aa}\simeq 2.3 M_{\odot}$, $M_{Ab}\simeq 2.2 M_{\odot}$) that are extended to $\sim 80\%$ of their Roche lobe radii ($R_{Aa}\simeq 4.3 R_{\odot}, R_{Ab} \simeq 4.0 R_{\odot}$), resulting in prominent ellipsoidal oscillations in the lightcurve. We also find that the primary is in a very special phase of its
evolution in which it has just finished core hydrogen burning. The remarkable combination of orbital and
stellar parameters hints that the historical brightening of Theta Eridani was due to a millenary transient phase powered by orbital energy extraction during a long-lived “common envelope” stage triggered by eccentric Roche lobe overflow in a previously more eccentric binary ($e\simeq0.6$). This strengthens the case that the apparent brightening was real and not due to an error by three different ancient observers, as has been commonly claimed in the past.
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High Energy Physics (Theory)
Super $T\bar{T}$ deformation and the RNS non-critical superstring
Marcelo R. Barbosa
In this paper we review the super $T\bar{T}$ deformation of $\mathcal{N}=(1,1)$ theories in the superspace formulation, alongside its interpretation in the context of noncritical string theory. By combining the superspace approach with concepts from the study of super-Riemann surfaces, we demonstrate that super $T\bar{T}$ deformations in superspace can be naturally interpreted as a noncritical RNS superstring theory. We also propose a possible interpretation of the super $T\bar{T}$ deformations as 2D supergravity in the superspace through some field redefinitions.
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Astrophysics of Galaxies
Introducing AuriGLOBES: The effects of compressive tides, compact object-induced mass loss, and size evolution on modelling globular clusters
Pablo Contreras Guerra, Robert J. J. Grand, Marta Reina-Campos et al. (+1 more)
Globular clusters (GCs) are long time survivors of
galaxy assembly and
evolution yet their emergence from an initial cluster population is still poorly constrained. We present the Auriga GLOBular clustEr Simulations (AuriGLOBES) a physically motivated subgrid model for
star cluster (SC) formation and
evolution that includes enhanced mass loss from compact object remnants. With this model, implemented in the Auriga cosmological
galaxy formation model, we run a suite of zoom-in cosmological simulations comprising 9 Milky Way mass and 5 lower mass
galaxies. We demonstrate that our model produces plausible GC populations compared to the Milky Way/M31 systems and reproduces the empirical GC system mass –
halo mass relation within a 2$\sigma$ scatter. We show that the formation of SCs in tidally compressive, high-pressure gas in addition to enhanced mass loss from compact object remnants heating is required to capture the transformation of an initial Schechter mass function to the characteristic observed GC mass function in the Milky Way/M31 systems. The resulting GC populations show spatial and
metallicity distributions qualitatively similar to the Milky Way/M31 systems, as well as a variety of age distributions that correlate with the
star formation history of the simulated
galaxies. However, the peak of the age distribution of Milky Way GCs is older than any of our simulated Milky Way-mass
galaxies, which is attributed to unrepresented
star formation and
galaxy assembly histories. AuriGLOBES represents a reliable framework for the study of GC populations through
cosmic history and a robust foundation for future applications for a model of
stellar streams arising from GCs disruption.
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All authors Pablo Contreras Guerra, Robert J. J. Grand, Marta Reina-Campos, Claudio Dalla Vecchia
Quantum Physics
Revivals of Bell nonlocality require Schrödinger and Heisenberg non-Markovianity
Federico Settimo, Kimmo Luoma, Jyrki Piilo et al. (+3 more)
Bell nonlocality is a key resource in
quantum information, demonstrating the nonclassicality of
quantum theory. Noise, however, is in general detrimental to nonlocality, and can cause the loss of the ability to violate any Bell inequality.
Memory effects, on the other hand, can restore this quantumness and, as recently shown, they can be differently characterized in the Schrödinger and in the Heisenberg picture. Here, we show that if
memory effects allow for revivals in time of nonlocality, then the dynamics must be non-Markovian in both pictures. We showcase our findings through a device-independent
quantum key distribution task, for which Bell nonlocality is necessary.
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All authors Federico Settimo, Kimmo Luoma, Jyrki Piilo, Andrea Smirne, Bassano Vacchini, Dariusz Chruściński
Optics
Adaptive Eigenvector Continuation for Full-Vector Photonic Waveguide Mode Emulation
Daniel Rodíguez-Guillén and Lorena Velázquez-Ibarra
Photonic waveguide design often requires repeated full-vector Maxwell eigenmode solves over wavelength, geometry, and material parameters. We present an adaptive eigenvector-continuation framework for accelerating and stabilizing these modal sweeps. The method constructs a reduced basis from selected full-order modal snapshots, solves projected Maxwell eigenproblems at new query points, reconstructs the modal fields, and monitors accuracy with a full operator residual. We demonstrate three regimes. In fixed-geometry wavelength sweeps of a strip waveguide, well-distributed snapshots reproduce the target modal branch with low residual and low effective-index error. In a multimode ridge waveguide, a shared reduced basis containing several modal families enables robust broadband mode-family tracking and residual-guided adaptive enrichment. In geometry-dependent width sweeps, the method gives accurate effective-index predictions and high field overlap, but the residual reveals moving-boundary errors caused by non-smooth changes of the discrete operator on a fixed Cartesian grid. These results show that adaptive eigenvector continuation is an operator-consistent modal emulator and diagnostic tool for photonic waveguide sweeps.
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Solar and Stellar Astrophysics
Star-Planet Interactions: Observational Techniques and Methods
P. Figueira, H. Korhonen, A. Buccino et al. (+8 more)
This chapter summarizes the techniques and methods used to study
star-
planet interaction (SPI) from the observational point of view. SPI can produce a wide range of observational signatures, from localized
stellar activity enhancements to changes in planetary atmospheric escape and transmission spectra. This chapter reviews the main observational techniques used to detect and characterize SPI, emphasizing the methodological challenges involved in separating
planet-induced signals from intrinsic
stellar variability. We discuss radial-velocity diagnostics, including cross-correlation, template matching, line-by-line methods, and activity indicators, highlighting their sensitivity to line-profile distortions and chromatic variability. We then review precision photometry as a tool to search for orbit-locked variability,
flare modulation, and active-region occultations during planetary transits. Chromospheric diagnostics, including Ca II, Halpha, He I, and Na II lines, are presented as tracers of
magnetic variability at different atmospheric heights and as potential probes of intermittent SPI signatures. We also discuss transmission spectroscopy as a complementary approach, since planetary atmospheric tracers such as H I Lyalpha, Balmer lines, C II, and He I can encode information about the
stellar high-energy environment,
stellar wind, and
magnetic coupling. In addition,
radio observations provide a promising avenue to probe
magnetic SPI directly through coherent emission mechanisms. Finally, we examine time-series analysis techniques commonly employed in SPI searches, including generalized Lomb-Scargle periodograms, rolling periodograms, harmonic analyses, and bootstrap-based significance estimation. (abridged)
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All authors P. Figueira, H. Korhonen, A. Buccino, P. Chaturvedi, R. Fares, A. García-Muñoz, B. Montet, L. Peña-Moñino, M. Pérez-Torres, D. Revilla, A. Valio
Astrophysics of Galaxies
ALMA visits the QSO MUSEUM: Connecting molecular gas and the cool circumgalactic medium around 37 $z\sim3$ quasars
Jelena Ritter, Fabrizio Arrigoni Battaia, Bo Peng et al. (+5 more)
Extended Ly$\alpha$ emission is ubiquitous around
quasars and traces the cool circumgalactic medium, providing insights into
halo gas dynamics and active
galactic nucleus feedback. However, its connection to the cold molecular gas of the host
galaxies remains largely unexplored. We characterize the molecular gas reservoirs of
quasars at $z\sim3$ and investigate their connection to extended Ly$\alpha$ emission using ALMA CO(4-3) observations of 37
quasars from the QSO MUSEUM survey, previously mapped in Ly$\alpha$ with VLT/MUSE. We derive molecular gas masses and gas fractions, explore correlations with Ly$\alpha$ nebula and
quasar properties, and search for CO-emitting companions. We detect 21/37
quasars in CO(4-3), with gas masses of $M_\mathrm{gas}\approx(3-40) \times10^9\,\mathrm{M_\odot}$.
Quasars with the most massive molecular gas reservoirs are associated with the centrally dimmest Ly$\alpha$ nebulae, while those hosting the centrally brightest Ly$\alpha$ nebulae are generally not detected in CO. This suggests that gas and
dust in the hosts regulate Ly$\alpha$ escape and consequently affect the emission from
halo gas. We find evidence that lower-Eddington-ratio
quasars harbor more massive gas reservoirs, while strongly accreting
quasars ($\lambda_\mathrm{Edd} \gtrapprox 0.9$) likely deplete their gas; for example, through powerful
quasar-driven
outflows. Despite their higher molecular gas masses within the sample, CO-detected low-Eddington
quasars exhibit low gas fractions with a median $M_\mathrm{gas}/M_* \sim 0.10$, below what is typically found for inactive
star-forming
galaxies. Six
quasars are marginally resolved in CO, with effective radii up to $\sim 8\,\mathrm{kpc}$. In addition, we detect 14 high-fidelity companion
galaxies, indicating overdense
quasar environments with a
quasar-
galaxy cross-correlation length of $9.81^{+2.22}_{-2.05}\,h^{-1}\mathrm{cMpc}$.
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All authors Jelena Ritter, Fabrizio Arrigoni Battaia, Bo Peng, Jay González Lobos, Chian-Chou Chen, Aura Obreja, Nahir Muñoz-Elgueta, Chiara Circosta
Quantum Physics
Theory and practice of Trotter product formulas for quantum chemistry
Pablo A. M. Casares, William Maxwell, Danial Motlagh et al. (+7 more)
Trotter product formulas are a fundamental class of methods for
Hamiltonian simulation, particularly attractive due to their low
qubit requirements. However, they are often overlooked for use with fault-tolerant
quantum algorithms, because of their perceived higher gate counts and the difficulty of estimating Trotter error. Here, we introduce
Symmetry-Protected Randomized near-Integrable Trotter (SPRINT) formulas, a framework for building optimized product formulas for electronic structure
Hamiltonians widely used in
quantum chemistry. SPRINT integrates a generalization of classical near-integrability, randomization,
symmetry protection, use of QROM, and other techniques into a thoroughly optimized methodology for
Hamiltonian simulation. When applied to concrete simulation tasks, we find SPRINT leads to substantial reduction in gate count compared to previous approaches. Alongside SPRINT, we introduce and analyze a Generalized Rank Decomposition (GRADE) of electronic
Hamiltonians that generalizes previous factorization methods. We apply these techniques to the task of simulating the X-ray absorption spectrum of Li$_4$Mn$_2$O, a candidate battery cathode material, leveraging recent advances in tight Trotter error estimation to carefully identify the best version of SPRINT for this problem. Using a Trotter error estimation tool developed in the PennyLane software platform, we show that SPRINT reduces the Toffoli gate cost by a factor of $4.5$ relative to the previous state of the art for this problem, with a gate cost only $\times 2.5$ higher than qubitization, while requiring a dramatic $\times 5.5$ fewer logical
qubits. These results establish well-designed Trotter product formulas as an attractive
Hamiltonian simulation method for industrially relevant problems in chemistry and materials science.
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All authors Pablo A. M. Casares, William Maxwell, Danial Motlagh, Hitarth Choubisa, Zy Niu, Ignacio Loaiza, Jonathan E. Mueller, Arne-Christian Voigt, Juan Miguel Arrazola, Stepan Fomichev
High Energy Physics (Phenomenology)
Dynamical evolution of the pressure on the bubble wall
Benoit Laurent and Miguel Vanvlasselaer
First-order phase transitions in the early Universe are pivotal for gravitational wave production, baryogenesis, and dark matter generation. A central question is whether bubble walls reach a subjouguet or ultra-relativistic velocity - a distinction governed by hydrodynamic obstruction, where
plasma heating counteracts the
vacuum pressure driving the wall. Traditional analyses assume steady-state fluid profiles, but these may fail during the wall's acceleration phase. We study the dynamical
evolution of the pressure on the bubble wall in local thermal
equilibrium (LTE), combining analytical approximations with numerical hydrodynamic simulations. Our results reveal that the heating wave's formation time often exceeds the wall's acceleration timescale, invalidating steady-state predictions near the Jouguet velocity. We derive a revised criterion for the maximal driving pressure, which separates deflagration/hybrid regimes from detonations/runaway walls. This criterion, validated by simulations, shows that hydrodynamic obstruction is less restrictive than steady state LTE predictions suggest.
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Cosmology and Nongalactic Astrophysics
Fuzzy Dark Matter Halo Mass Functions at Cosmic Dawn
Raghunath Ghara, Adam Lidz, Daniel Grin et al. (+1 more)
In fuzzy dark matter (FDM) cosmological models, wave effects impact astrophysical length scales, suppressing the abundance of small mass dark matter
halos, and delaying the earliest phases of
galaxy formation during
Cosmic Dawn. Current and upcoming James Webb Space
Telescope (JWST) measurements of the
galaxy ultraviolet luminosity function (UVLF) will allow unprecedented tests of this suppression, yet significant uncertainties remain in theoretical models of the FDM
halo mass function. We run a new suite of N-body simulations with FDM particle masses of $mc^{2}=10^{-22}\,{\rm eV} - 2 \times 10^{-21}$ eV and mixed FDM-cold dark matter (CDM) models with FDM mass fractions of $f_{\mathrm{F}} = 0.3-1$. We identify and remove spurious
halos from discreteness noise and quantify the associated systematic uncertainty. We provide a new
halo mass function fitting formula, calibrated over $z=6-11$, applicable to pure FDM and mixed dark matter scenarios. Our results are in better agreement with previous simulation-based fitting formulas than with current semi-analytic mass function models. Nevertheless, for $m c^{2} = 10^{-21}$ eV and $M \sim 3 \times 10^9 M_\odot$ we find a $\sim 30\%$ weaker suppression than earlier simulation-based formulas predict, which we attribute to their extrapolation beyond the $m_{\rm FDM}$ range previously simulated. Applying our fitting formula to the UVLF, we find that upcoming JWST observations behind foreground
lensing clusters, probing $M_{\rm UV} \gtrsim -13$ at $z \gtrsim 10$, will provide a powerful test of FDM and mixed dark matter models.
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All authors Raghunath Ghara, Adam Lidz, Daniel Grin, Jackson Sipple
Quantum Physics
Practical Estimation of Trotter Error for Hamiltonian Simulation
William Maxwell, Pablo A. M. Casares, Robert A. Lang et al. (+7 more)
Trotter product formulas are a leading approach for
Hamiltonian simulation on
quantum computers, yet their practical performance has remained difficult to assess due to the challenge of accurately estimating the Trotter error. In this work, we develop new theoretical results,
algorithms, and software tools that advance the state-of-the-art in Trotter error estimation by orders of magnitude in both scale and accuracy. On the theoretical side, we prove that in the asymptotic limit the error of a product formula depends on the diagonal elements of the Baker-Campbell-Hausdorff (BCH) error operator in the eigenbasis of the
Hamiltonian, rather than its full spectral norm – yielding an improved scaling for
Hamiltonian simulation using product formulas. On the algorithmic side, we introduce a compact representation of the BCH expansion that reduces the number of commutators from $\mathcal{O}(n^3)$ to $\mathcal{O}(n)$ for second-order, and from $\mathcal{O}(n^5)$ to $\mathcal{O}(n^2)$ for fourth-order formulas on $n$ fragments, complemented by an importance sampling scheme to further reduce the computational cost. We provide implementations of these techniques in software and demonstrate their power on two applications: (i) X-ray absorption spectroscopy of an electronic
Hamiltonian (Li$_4$Mn$_2$O) at up to 56
qubits using tensor networks; and (ii) vibronic dynamics of naphthalene at over 100
qubits using ML-MCTDH, where we find that naive analytical bounds overestimate the required number of Trotter steps by nearly five orders of magnitude. Our framework enables, for the first time, the accurate estimation of Trotter error at practically relevant system sizes, providing a foundation for fair algorithmic comparisons and rational design of product formulas.
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All authors William Maxwell, Pablo A. M. Casares, Robert A. Lang, Stepan Fomichev, Juan Miguel Arrazola, Soran Jahangiri, Ali Asadi, Luis Alfredo Nunez Meneses, Thomas Germain, Danial Motlagh
High Energy Physics (Phenomenology)
$\Lambda \bar \Lambda$ spin correlations in high-energy collisions from quantum channels: an open quantum system view of hadronization
João Barata, Iván Cuntín, Enrique Rico et al. (+1 more)
We construct a
quantum information-centered approach to describe the experimentally observed behavior of hyperon
spin-pair correlations in high-energy
collider experiments. The
evolution of the
spin density
matrix of the hyperon pair is treated in the
language of
quantum channels, accounting both for the
spin dynamics in $\mathbb{C}^2\otimes\mathbb{C}^2$ and for the pair's angular separation $\Delta R$. We show that the experimental data are consistent with an
evolution under a two-
qubit depolarizing channel, from which a Lindblad master equation is derived. This provides an open
quantum system picture of
spin dynamics during the hadronization transition, which is not naturally captured by other
quantum channels, and we discuss its microscopic origins. These results show that
quantum information science can offer new insights into confinement dynamics beyond the classification of
entanglement in the final particle states.
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All authors João Barata, Iván Cuntín, Enrique Rico, Bin Wu
Astrophysics of Galaxies
Gravitational-Electric Polarization as a Probe of Dark Matter and Modified Gravity
Nirupam Roy
Self-gravitating astrophysical
plasmas naturally achieve a state of global electrical polarization, known as the Bally-Harrison effect, where an induced electric field counteracts the preferential thermal escape of electrons. In this work, we revisit the phenomenon of gravitational-electric polarization in astrophysical
plasmas. By accounting for the dominant role of dark matter and comparing results across modified
gravity frameworks, including MOND and MOG, we provide new constraints on the global charge-to-mass ratios of
galaxies and clusters. We demonstrate that the effective charge-to-baryonic-mass ratio Q/M_bar is enhanced by a factor of 10 - 30 at the virial radii relative to purely baryonic predictions. By coupling gravitational polarization to
galactic rotation, we derive a structurally linked seed field that reaches ~10^{-23} G in high-
redshift proto-
galaxies, sufficient for rapid dynamo saturation. We demonstrate that the distinct spatial signatures of these fields across different
gravity theories provide a potential observational probe of the dark sector in the early universe. This enhancement may have significant implications in inferring properties of the intracluster medium and in determining the
primordial seed
magnetic field. The distinct radial and mass-dependent scaling laws predicted for each paradigm also provide a plausible diagnostic to distinguish between the presence of invisible mass and modifications to the gravitational law.
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Quantum Physics
Disorder-Induced Enhancement of Fermionic Superradiance
David Pascual Solis, Andrea Legramandi, Soumik Bandyopadhyay et al. (+1 more)
Collective light-matter phenomena such as Dicke superradiance are often described as a collection of effective
spins coupled homogeneously to a bosonic mode, giving rise to a collective bright mode with enhanced light-matter coupling. In fermionic systems, Pauli exclusion and
Fermi-surface structure can significantly modify this picture, while randomness in the atom-light couplings raises the question of whether disorder promotes or suppresses collective behavior. Here, we study a cavity model in which fermionic particles couple to a photonic mode through a random all-to-all interaction
matrix with tunable mean and variance. Combining numerical mean-field methods, analytic stability analysis and random-
matrix predictions, and
benchmarks against exact diagonalization, we characterize both the onset and structure of the superradiant phase. While mean coupling and disorder variance contribute in the same way to the onset, they lead to drastically different behavior within the condensed phase. Uniform coupling supports a single bright collective fermionic mode with conventional Dicke-like scaling of the cavity field. Disorder, instead, gives rise to a qualitatively different collective regime in which many grey fermionic states participate coherently, producing a parametrically enhanced scaling of the condensate with system size. Our results reveal a mechanism through which disorder can, perhaps counterintuitively, promote collective light-matter phenomena.
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All authors David Pascual Solis, Andrea Legramandi, Soumik Bandyopadhyay, Philipp Hauke
Astrophysics of Galaxies
Jarrett Johnson, Phoebe Upton Sanderbeck, Nicole Lloyd-Ronning et al. (+2 more)
It has recently been suggested that a variety of data on active
galactic nuclei (AGN) can be explained if AGN disks are supported against gravitational fragmentation by
magnetic fields that are advected into the disk from the surrounding
galaxy. Here we derive the maximum timescales over which
accretion onto a black hole (BH) powering an AGN can be maintained at a given rate, both with and without
magnetic disk support. We then compare these timescales to the lifetimes of episodes of sustained luminous
accretion that are inferred from measurements of the photoionized proximity zones around high-
redshift quasars. While some of the shortest inferred
quasar lifetimes are consistent with pure gas pressure support, we find that some additional
magnetic support is likely required to explain the longest inferred
quasar lifetimes of > 10$^4$ yr. For these longest-lived AGN, we find that
magnetic pressure in their disks can be up to a hundred times higher than the gas pressure. In addition, the lack of inferred
quasar lifetimes that are definitively > 10$^6$ yr is consistent with gas pressure and advected
magnetic fields being the principal sources of disk support. This adds to the body of evidence that
magnetic fields play an important role in sustaining the rapid growth of supermassive BHs in the early universe.
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All authors Jarrett Johnson, Phoebe Upton Sanderbeck, Nicole Lloyd-Ronning, Madeline Marshall, Kelcey Davis
Solar and Stellar Astrophysics
The Companions to B and A Stars Snapshot (C-BASS) Survey: I. Discovery of a Young Brown Dwarf Companion to HIP 17453
Marah Brinjikji, Adam J. Smith, Jennifer Patience et al. (+26 more)
We report the detection of a new brown
dwarf companion to HIP 17453 A, a chemically peculiar A0V
star located at a distance of 81 pc. HIP 17453 A was observed with high-resolution adaptive optics imaging using the Near-Infrared Camera 2 on the Keck II
telescope as part of the Companions to B and A
Stars Snapshot (C-BASS) survey over a ten-year baseline, revealing the presence of a companion with proper motion consistent with the primary. We estimate the age of the HIP 17453 system as 280 $\pm$ 125 Myr, and with follow-up intermediate resolution (R~1800) spectroscopic observations with the Gemini Near Infra-Red Spectrograph (GNIRS) on the Gemini-North
telescope, we found the spectrum of HIP 17453 B to be consistent with a spectral type of L2 $\pm$ 1. Through interpolation of Sonora Diamondback evolutionary models, we calculate an effective temperature of $1953^{+84}_{-78}$ K and mass of $53^{+10}_{-8}$ $M_{Jup}$ for HIP 17453 B, which corresponds to a mass ratio of $q = 0.024 \pm 0.004$ for the HIP 17453 system. With its intermediate mass and young age, HIP 17453 B joins a small set of
benchmark brown
dwarf companions around early-type
stars that are suitable for follow-up atmospheric and evolutionary studies.
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All authors Marah Brinjikji, Adam J. Smith, Jennifer Patience, Eric Nielsen, Austin Ware, Jorge A. Sanchez, Robert J. De Rosa, Jasmine Garani, Emma Softich, Michael C. Liu, Bruce Macintosh, Thomas M. Esposito, Brendan P. Bowler, William M. Best, Sarah Blunt, Trent Dupuy, Justin Hom, Jessica A. Klusmeyer, Franck Marchis, Jayke S. Nguyen, Anne E. Peck, Mark W. Phillips, William Roberson, Jean-Baptiste Ruffio, William Thompson, Zahed Wahhaj, Samuel A. Walker, Jason J. Wang, Patrick A. Young
Strongly Correlated Electrons
Magnetic Bloch Oscillations in Odd-Wave Magnets and the Nonlinear Edelstein Effect
Jonas Habel and Johannes Knolle
Bloch oscillations (BOs) are a
quantum phenomenon in which electrons subjected to an electric field in a periodic potential exhibit an oscillating current without a net drift. In real conductors, scattering reduces the coherence required for BOs driving the system toward a steady state with a DC current. While previous studies have focused on charge transport, charge carriers also possess
spin, raising the question of whether BOs can emerge in
magnetic observables. Here, we show that the magnetization of odd-wave magnets can undergo BOs before relaxing to the steady-state Edelstein value, a phenomenon we term $\textit{magnetic}$ BOs. Using analytical and numerical methods, we demonstrate this effect in a minimal one-dimensional model of a p-wave magnet and generalize it to two dimensions. Our analysis further reveals that the Edelstein magnetization is generically nonlinear in the applied electric field. Finally, we argue that
magnetic BOs can be detected in materials through higher-harmonic generation in THz sub-cycle lightwave spectroscopy.
Magnetic BOs provide a genuine non-
equilibrium signature of
spin-charge coupling in unconventional magnets.
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High Energy Physics (Theory)
Half-BPS Boundaries and the RG-Wall of $\mathcal{N}=2$ $SU(N)$ SYM
Riccardo Comi and Simone Rota
We identify the 3d theory that realizes the RG-wall interface of 4d $\mathcal{N}=2$ $SU(N)$ Super-Yang-Mills, interpolating between the UV Lagrangian and the IR Seiberg-Witten effective description. The same theory also describes the low-energy boundary condition that corresponds to giving half-BPS Dirichlet boundary condition in the Lagrangian description of 4d $\mathcal{N}=2$ $SU(N)$ SYM. The theory is a 3d $\mathcal{N}=2$ SCFT that can be obtained as a massive deformation of the $T[SU(N)]$ theory, which is the S-duality interface of 4d $\mathcal{N}=4$ $SU(N)$ SYM. As the main validating tests, we match half-indices and discuss non-trivial consistency conditions when colliding such interfaces.
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Quantum Physics
Controlling the non-Markovianity of quantum Brownian motion
Guglielmo Pellitteri, Vittorio Giovannetti and Vasco Cavina
We analyze the exact dynamics of a generalized
quantum Brownian motion model, employing Gaussian master equation methods. We demonstrate that, by modulating the relative weights of specific interaction channels, we can control the degree of non-Markovianity of the system, and induce a transition from non-Markovian to Markovian regimes. The non-Markovianity of the
evolution is formally characterized by leveraging the Gorini–Kossakowski–Sudarshan–Lindblad
theorem and by employing quantitative measures of information backflow. Finally, we clarify the physical mechanism behind the phenomenology of this model, thereby providing a systematic platform for environment engineering through the strategic tuning of dissipation channels.
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General Relativity and Quantum Cosmology
Ray tracing ultracompact boson stars: visibility modulations and incomplete photon rings
Seppe J. Staelens and Ece Alkan
Modified black holes and black hole mimickers can give rise to additional
photon rings in ray-traced images. With the
photon ring structure of Kerr well understood, the question arises how well future versions of the Event Horizon
Telescope images would be able to constrain the presence of non-Kerr
photon rings. In this work, we investigate how likely additional
photon rings are to present themselves through low-frequency modulations of the visibility amplitude, i.e. in
Fourier space where the data live. To this end, we generate ray-traced images of stable and unstable ultracompact, solitonic
boson stars, both in spherical
symmetry and with rotation. We find that clear modulations in the associated visibility amplitude are only present in spherical
symmetry, for a restricted range of observer inclinations, hence suggesting that these modulations can not be a generic expectation of ultracompact black-hole mimickers. Additionally, we discuss how the
photon rings are incomplete for the rotating
boson stars considered, and how an unstable prograde light ring may be needed to remedy this.
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High Energy Physics (Theory)
Radial Solutions of Multi-Field de Sitter Galileons
Alice Garoffolo, Mary Gerhardinger, Kurt Hinterbichler et al. (+1 more)
We study static, spherically symmetric screening solutions in the $\mathfrak{so}(N)$-invariant multi-field de Sitter Galileon theory, with matter couplings preserving the internal
symmetry. Unlike in flat space, the de Sitter radial problem is affected both by the cosmological horizon and by the possible appearance of a finite strong-coupling radius, where the radial equation becomes singular and the effective description breaks down. Near the source, the quartic interaction governs the nonlinear screened branch, while farther away the quadratic terms dominate, defining a de Sitter analog of the Vainshtein radius at their crossover. A screened solution is viable only if this crossover occurs before the strong-coupling radius is reached. We study perturbations around the radial background and identify branches for which perturbations are stable and subluminal, within a restricted radial domain set by the strong-coupling point. Finally, we compare the de Sitter and Anti-de Sitter cases, isolating effects due to
curvature from those specific to the cosmological horizon. Our results indicate that
curvature can alleviate the superluminality issues that arise in Galileon theories for appropriate choices of matter couplings, though this comes at the price of a finite region of validity for the effective theory.
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All authors Alice Garoffolo, Mary Gerhardinger, Kurt Hinterbichler, Mark Trodden
Astrophysics of Galaxies
A new era for Dual AGN science with SHARP
P. Severgnini, C. Vignali, A. De Rosa et al. (+21 more)
The search for and the characterization of ultra-compact dual active
galactic nuclei (AGN) are among the hottest topics of current extragalactic astrophysics. These systems involve two accreting massive black holes (MBHs) embedded within the same host
galaxy, with relative projected separations from a few hundred pc down to a few pc. They are central to understanding hierarchical
galaxy formation, black hole growth and demographics, and
accretion-feedback coupling in the most extreme interaction phases. Even more compellingly, such tight pairs are the most direct precursors of gravitationally bound binary MBHs (sub-pc scale separation), which are among the loudest emitters of gravitational waves (GWs) in the low-frequency ranges. SHARP will deliver the first statistical census and physical characterization of ultra-compact dual AGN up to
cosmic distances, finally bridging the observational gap between kpc-scale pairs and sub-pc GW-emitting binaries, and enabling a breakthrough understanding of MBH growth, feedback and co-
evolution across
cosmic time.
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All authors P. Severgnini, C. Vignali, A. De Rosa, E. Portaluri, F. Rigamonti, L. Battistini, L. Bertassi, E. Bertola, S. Bianchi, E. Bortolas, C. Cicone, Q. D'Amato, R. Della Ceca, I. Delvecchio, M. Dotti, J. Harms, I. Lamperti, F. Mannucci, M. Parvatikar, B. Sala, M. Scialpi, R. Serafinelli, J. Singh, M.V. Zanchettin
Astrophysics of Galaxies
AGN-driven outflows in dwarf galaxies from cosmological simulations: Internal properties and observational signatures
Elena Arjona-Gálvez, Arianna Di Cintio, Robert J. J. Grand et al. (+4 more)
While AGN feedback is a key driver of massive
galaxy evolution, its physical properties and observational signatures in the
dwarf regime remain poorly understood. We investigate the impact of AGN-driven
outflows on the ISM of
dwarf galaxies and assess whether these events can be robustly identified through emission-line diagnostics. We analysed a high-resolution cosmological magneto-hydrodynamical zoom-in simulation from the AURIGA project. We focused on a
dwarf galaxy with 1e9.7 M*/Msun hosting a BH of 1e7 Msun. We identified individual
outflow episodes via pressure peaks in the gas surrounding the central BH, tracked the thermodynamic and kinematic history of such gas, and computed synthetic, spatially resolved nebular emission using photoionisation models to construct BPT diagnostic diagrams. We show that AGN activity in this regime produces compact, over-pressurised central bubbles reaching >1e6 K temperatures. These structures accelerate the ISM up to 600km/s, exceeding those driven by
stellar feedback: the outflowing material does not escape the
halo, but instead decelerates and redistributes within 10kpc from the
galaxy center. Synthetic emission-line modelling reveals clear, time-dependent signatures of such AGN-driven feedback. Over its life cycle, the simulated AGN-hosting
galaxy traces the locus of observed
dwarf AGNs and migrates from the SF sequence in the BPT diagrams through the composite region into the AGN regime, highlighting a self-regulation mechanism in which the BH accretes its fuel supply, progressively moving towards the low-ionisation
nuclear region. Our results suggest that AGN-driven
outflows in
dwarfs primarily regulate the central ISM through episodic heating and rapid gas recycling, rather than large-scale gas ejection. These processes generate observable spectroscopic signatures, offering a promising avenue for identifying AGN feedback in low-mass
galaxies.
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All authors Elena Arjona-Gálvez, Arianna Di Cintio, Robert J. J. Grand, Laura V. Sales, Gabriela Canalizo, Teresa Matamoro Zatarain, Aswin P. Vijayan
High Energy Physics (Theory)
Constrained particle on a group: from propagators to correlators
Guanda Lin
We develop a particle-on-a-group formulation of super-JT
gravity aimed at computing supersymmetric correlators. We show that the (super)JT
gravity can be described by a particle moving on the isometry group satisfying constraints from boundary conditions of (super)JT
gravity. In this
language the $\mathcal N=2$ and $\mathcal N=4$ theories are described by constrained particles on $SU(1,1|1)$ and $PSU(1,1|2)$. Solving the constraints gives the super-Schwarzian actions. We also quantize the reduced superparticle, with careful treatment of the fermionic constraints. We then derive the physical worldline supercharges from the requirement that the transformations preserve the constraints. These charges allow us to construct supersymmetric interval propagators in invariant variables and to formulate boundary-anchored Wilson-line operators for both superconformal primary and descendant insertions. Finally, we use these ingredients to build an
algorithm for correlators. We obtain the $\mathcal N=2$ and $\mathcal N=4$ three-point composition kernels and zero-energy scalar three-point functions. For four-point functions, the same method reproduces the standard bosonic JT OTOC, gives an explicit zero-energy OTOC in $\mathcal N=2$ and $\mathcal N=4$ SJT, which is potentially useful for studying Berry
curvature and BPS chaos.
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High Energy Physics (Phenomenology)
Boosted Dark Matter from Sagittarius A$^\star$
Javier F. Acevedo and Adam Ritz
It was recently demonstrated that black hole binaries can gravitationally accelerate ambient dark matter (DM), producing a continuous flux of particles with velocities far exceeding those of the
galactic halo. We extend this analysis to the Milky Way's
nuclear star cluster, where
stellar-mass black holes are expected to orbit in close proximity to the supermassive black hole Sagittarius A$^\star$. Using numerical simulations, we compute the flux of gravitationally-boosted DM sourced by this region. Because of the high DM density and large population of black holes orbiting deep within Sagittarius A$^\star$'s gravitational potential, the resulting DM ejecta attain substantially higher rates and energies compared to
galactic black hole binaries, with simulated particles reaching velocities of up to $\sim 25,\!000 \, \rm km/s$. We find that the
nuclear star cluster is therefore the dominant source of gravitationally-boosted DM in the Milky Way. Even under conservative assumptions about the DM profile in the inner
galaxy, the ejected DM flux from this region can render large-volume DM detectors competitive with lower-threshold experiments in the sub-GeV mass range, independently of the underlying DM particle model. The gravitational nature of the boost also opens up a sizable detection window into heavy inelastic DM scenarios that are otherwise largely inaccessible to conventional
halo DM searches.
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High Energy Physics (Theory)
Ryu-Takayanagi area from Virasoro modular data
Jennifer Lin
We show that in
holographic 2d CFTs, the
entanglement entropies across several choices of global state and subregion can be written in a way that at once has a microscopic interpretation and matches the leading large$-c$ organization of the Ryu-Takayanagi formula. This representation is obtained by applying crossing
symmetry to the replica
manifolds. From the boundary point of view, each rewritten
entropy looks like an algebraic
entanglement entropy for the Virasoro
algebra restricted to the region, with center labels obtained by coarse-graining heavy primaries of the BCFT on the regulated region into bins labeled by Liouville momenta. At large $c$, a resulting sum over bins is dominated by a saddle, and the $O(c)$ part of the
entropy comes from the Cardy density of heavy primaries in the dominant bin. We identify this $O(c)$ part of the
entropy with the Ryu-Takayanagi area. Physically, this suggests a concrete statistical origin for the Ryu-Takayanagi area as coming from coarse-grained Virasoro intertwiners across the entangling cut. The result also provides quantitative criteria for the amount of coarse-graining allowed for the consistency of the interpretation.
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Earth and Planetary Astrophysics
Chemical Abundances of the Bioessential Elements C, O and S, and the Refractory Elements Fe and Ni, in Solar-type Exoplanet-hosting Stars from HARPS North and South
E. Costa-Almeida, L. Ghezzi, K. Cunha et al. (+2 more)
We determined atmospheric and evolutionary parameters, along with chemical abundances of C, O, S, Fe, and Ni for 290
solar-type
exoplanet hosting
stars using high-resolution HARPS-North and HARPS-South spectra, and radii for 373
exoplanets using literature transit depths. We find that
stars hosting
giant exoplanets (R$_{\text{pl}}>4\ \text{R}_{\oplus}$) show enhanced [X/H] abundances compared to small
exoplanet hosts for all elements analyzed. When considering only
exoplanets with $P_{\text{orb}}\leq30$ days, there is a statistically significant anti-correlation between host
star [Fe/H] and $P_{\text{orb}}$. However, [Fe/H] does not continue to decline as the orbital period increases, but rather rises again for
exoplanets with larger orbital periods.
Stars hosting only small
exoplanets or hosting at least one sub-Saturn show significant differences between the populations of hot and warm
exoplanets for all elements. In contrast,
stars hosting at least one Jupiter-sized
planet show no abundance differences. The host
star C/O ratios obtained vary from 0.17 to 0.95, with
giant exoplanet hosts exhibiting the lowest median C/O ratios (0.43$^{+0.02}_{-0.03}$), while the 3 – 4 R$_\oplus$ sub-Neptune hosts in our sample exhibit the highest median C/O ratios (0.55$^{+0.05}_{-0.01}$). Our sample has 199
exoplanets with estimated masses and we find correlations between host
star [O/H] and [S/H] and $\log(M_{\text{pl}}/\text{M}_\oplus)$. When segregating the sample into hot and warm
exoplanet hosts, these trends are only found for warm
exoplanets. Dividing the sample between low- (91
exoplanets) and high-[$\alpha$/Fe] (20
exoplanets)
stars, there are trends between host
star [O/H], [S/H], [Fe/H] and [Ni/H] and $\log(M_{\text{pl}}/\text{M}_\oplus)$ only for the low-[$\alpha$/Fe] sample.
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All authors E. Costa-Almeida, L. Ghezzi, K. Cunha, V. V. Smith, J. J. Fortney