High Energy Physics (Phenomenology)
Detecting Cosmological Stasis with Future Gravitational Wave Observatories
Gabriela Barenboim and Anne-Katherine Burns
We map the observational predictions of cosmological stasis in the inflationary gravitational wave background onto the sensitivity bands of current and planned gravitational wave detectors. Using the closed-form piecewise spectral template derived in the companion paper, we generate detectability maps for four stasis scenarios: canonical, dynamical scalar,
vacuum-energy/matter, and
vacuum-energy/radiation across the frequency bands probed by NANOGrav, SKA, LISA, DECIGO, BBO, the Einstein
Telescope, and
Cosmic Explorer. For scenarios in which the spectrum is suppressed, $w_s < 1/3$, the stasis feature is detectable by BBO in the region of $(w_s,\Delta N)$ parameter space in which $w_s\gtrsim 0.2$ for tensor-to-scalar ratios close to the Planck upper limit, r = 0.036. For scenarios in which the spectrum is enhanced, $w_s > 1/3$, the stasis feature is detectable by BBO across the entire $(w_s,\Delta N)$ parameter space for tensor-to-scalar ratios of $O(0.01)$. We characterize the Standard Model (SM) $g_*$ fine structure of the IGWB, showing that SM phase transitions introduce spectral steps of $\approx 20\%$ (electroweak, at $\sim 2.6\times10^{-6}$~Hz) and $\approx 53\%$ (QCD, at $\sim 3.6\times 10^{-9}$~Hz). For stasis scenarios with end-of-stasis temperatures below the QCD scale these steps fall inside the stasis band and constitute additional spectral features that complement the primary signature. Finally, we model the finite-width end-of-stasis transition phenomenologically, demonstrating that the spectral break at $f_{end}$ is smoothed over a log-frequency window $\Delta N_\mathrm{trans}\times 3(1+w_s)/4$, and that the consistency relation $C^2=C^2(\alpha)$ remains testable provided $\Delta N_\mathrm{stasis}\gg \Delta N_\mathrm{trans}$, a condition easily satisfied for all scenarios of phenomenological interest.
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High Energy Physics (Theory)
Global Asymptotics, the Swampland Conjectures, and Preheating of String Moduli
Leia Price, Kuver Sinha and Robert Wiley Deal
While the cosmological implications of the Swampland
Conjectures are usually discussed in the context of inflationary model building, they also have implications for the violent, non-adiabatic dynamics that can follow inflation or any displacement of string
moduli. We study this question through the lens of self-resonant preheating, where we point out that two Swampland motivated structures play central roles. The first is the local
curvature of the potential: the tachyonic branch of the refined de Sitter
Conjecture singles out the kind of negative
curvature that can drive tachyonic amplification. We show, however, that local
curvature data is not enough; the large field asymptotics of the potential determines how the modulus samples the unstable region. Thus, plateaus, barriers, and runaways can lead to different resonance efficiencies; we study tachyonic resonance for bulk
moduli in LVS and KKLT compactifications, as well as for typical blow-up
moduli potentials and alpha-attractor models. The second Swampland motivated structure pertains to the tower of light states predicted by the Swampland Distance
Conjecture. Modeling a finite subset of such states as an effective
stochastic environment within which a string modulus preheats, we find that the light states mainly reshape existing resonance bands by smearing, shifting, and mildly seeding instabilities, rather than opening a robust new reheating channel. Our results suggest that Swampland physics affects preheating by controlling both the deterministic
curvature structure of the potential as well as
stochastic corrections from emergent light states.
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Cosmology and Nongalactic Astrophysics
Detection of cosmic strings by gravitational wave lensing. Predictions for Einstein Telescope
Jakub Szyndler and Tomasz Bulik
Cosmic strings are not yet confirmed, topological defects formed in the early Universe. They can bend light or gravitational waves, which causes an effect similar to the gravitational
lensing. Our goal is to check whether
cosmic string could be detected as a lenses of gravitational waves by the Einstein
Telescope (ET). To do that the apparatus of wave optics had been applied. Firstly we explored the amplification factor strength and behaviour. Next the wave effects in SNRs and waveforms was examined for different inclinations of the source. Lastly we estimated the string tensions based on eight mergers from the StarTrack simulation, using the
Bayesian Inference methods. The wave effects were easily to see in waveforms, SNR and characteristic strains. Also most of the events could be detected, based on their Signal to Noise Ratio values. Almost whole characteristic strain lies in the range of the ET. When it comes to mock observations, we had got estimated vale of a logarithm of the CS tension equal to $\bar{\log{G\mu}}=-9.80^{+0.49}_{-0.56} $, which were consistent with injected value equal to $-10$. At the end we conclude that CSs could be detected by the ET.
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Astrophysics of Galaxies
Vz-GAL Dusty Star-Forming Galaxies: Revisiting the CO-H2 Conversion Factor Tension
Prachi Prajapati, Axel Weiss, Dominik Riechers et al. (+17 more)
The CO luminosity-to-H$_2$ mass conversion factor ($\alpha_{CO}$) remains a debated uncertainty in determining molecular gas masses of high-
redshift dusty
star-forming
galaxies (DSFGs). Dynamical mass constraints have often favored $\alpha_{CO}=0.8$~$M_{\odot}~{(K~km~{s}^{-1}~{pc}^{2})}^{-1}$, whereas
dust- and radiative-transfer-based methods imply higher values. We revisit this “tension" using the largest homogeneous sample of 21 unlensed $z\sim1-4$ DSFGs, with securely measured \coonezero luminosities from the VLA \vzgal survey and resolved ($\sim{0.1}^{\prime\prime}$) ALMA 1~mm
dust continuum imaging. For 12
galaxies with robust modeling constraints, we derive molecular gas masses using
dust spectral energy distribution modeling and the TUNER LVG framework, adopting a
solar-
metallicity gas-to-
dust mass ratio of 100. Although not fully independent due to shared assumptions on
dust properties, these approaches yield mutually consistent gas masses corresponding to $\alpha_{CO}\sim1.5-11.5$, with a median near the
Galactic $\alpha_{CO}=4.3$. Isotropic virial dynamical masses agree with these gas masses when realistic molecular gas sizes are adopted, while our proposed “mixed" (rotating, pressure-supported, thick-disk)
estimator systematically underestimates dynamical masses, producing low $\alpha_{CO}$ limits. Using GN20 ($z=4.055$) as a case study, we show that resolved gas geometry and kinematics reconcile the discrepancy with LVG-derived $\alpha_{CO}$. Our results suggest that current data do not require $\alpha_{CO}=0.8$, and intermediate to near-
Galactic values remain dynamically viable given uncertainties in gas geometry,
dust properties, and gas-to-
dust ratios. Further progress in calibrating $\alpha_{CO}$ in the early universe will require resolved molecular gas observations, physically motivated ISM modeling, and stringent constraints on
dust properties.
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All authors Prachi Prajapati, Axel Weiss, Dominik Riechers, Tom J. L. C. Bakx, Leindert A. Boogaard, Diana Ismail, Pierre Cox, Andrew J. Baker, Roberto Neri, Matthew Lehnert, Chentao Yang, Emilio Romano-Diaz, Hiddo S. B. Algera, Stefano Berta, Edoardo Borsato, Kirsty M. Butler, Asantha Cooray, Bethany Jones, Amelie Saintonge, Paul van der Werf
High Energy Astrophysical Phenomena
Can We Find the Emission Mechanism Behind the Extremely Bright GRB 230812B?
Utkarsh Pathak, Sameer K. Patil, Hitesh Tanenia et al. (+23 more)
GRB 230812B is a bright long-duration GRB with a luminous, long-lived afterglow and an AstroSat/CZTI polarization measurement during the
prompt phase, enabling a joint study of its
prompt spectral
evolution, polarization, and broadband afterglow. Time-resolved spectroscopy of the
prompt emission shows that during the rising phase, the low-energy Band-function index exceeds the synchrotron line of death, favoring the presence of an additional thermal component. At later times, from $T_0+2$ s to $T_0+32$ s, the
prompt spectra are consistent with predominantly non-thermal emission. Polarization analysis of the
prompt emission in the $300$-$600$ keV band yields a marginal lower limit on the polarization fraction of $\Pi \gtrsim 50\%$ at the $1\sigma$ level. The long X-ray monitoring of the afterglow shows no jet break over the observed baseline. Multiwavelength afterglow modeling favors a wide jet with an inferred half-opening angle of $\theta_j = 15^{+6}_{-4}$ degrees observed close to the jet axis with a viewing angle of $\theta_v = 0.9^{+1.8}_{-0.6}$ degrees. The inferred circumburst density is low, $n_0 = 1.2^{+0.3}_{-0.1}\times10^{-4}\,\textrm{cm}^{-3}$, and the isotropic-equivalent kinetic energy of the jet is $E_{{\rm k}, iso} = 4.0^{+1.5}_{-0.8} \times 10^{53}$ erg. Taken together, the
prompt spectral
evolution favors an early phase with a thermal contribution followed by a later phase dominated by non-thermal emission. The polarization constraint in the late
prompt phase is consistent with synchrotron emission, although a higher-significance polarization measurement will be required to robustly constrain the
magnetic-field geometry and the relative contribution of photospheric emission.
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All authors Utkarsh Pathak, Sameer K. Patil, Hitesh Tanenia, Yashowardhan Rai, Viswajeet Swain, Anuraag Arya, Gaurav Waratkar, Anirudh Salgundi, Mehul Goyal, Varun Bhalerao, Igor Andreoni, Sarah Antier, G. C. Anupama, Sudhanshu Barway, Dipankar Bhattacharya, Tanmoy Chattopadhyay, Michael Coughlin, Anirban Dutta, Christoffer Fremling, Nidhal Guessoum, Mansi Kasliwal, Oliver J. Roberts, Gokul P. Srinivasaragavan, Rishabh Singh Teja, Santosh Vadawale, Peter Veres
Quantum Physics
Bright Telecom Spin-Photon Interface in Silicon Photonics
Carolina Crosta, Amirehsan Alizadehherfati, Purbita Purkayastha et al. (+5 more)
Silicon is an attractive host for scalable
quantum photonics, but the absence of bright telecom-band emitters with optically addressable
spin states has limited its use for
spin-
photon interfaces. Here we demonstrate the Al1-center, an aluminum–carbon defect in silicon, as a bright waveguide-integrated single-
photon emitter with a ground-state
spin. Using isotopically purified silicon-on-
insulator nanophotonic devices, we isolate individual Al1-centers and observe high-purity single-
photon emission with $g^{(2)}(0)=0.04$ without background subtraction. Time-resolved photoluminescence spectroscopy reveals a fast excited-state lifetime of 135 ns, nearly an order of magnitude shorter than the
benchmark provided by the well-studied T-center. Resonant photoluminescence excitation measurements further resolve the zero-
phonon transition and reveal a narrow homogeneous linewidth reaching 47 MHz, threefold narrower than the T-center under comparable temperature. Through magneto-optical spectroscopy, we resolve the
spin-dependent transitions of the bound-
exciton manifold and achieve
spin-selective optical pumping, fulfilling the prerequisite for
quantum state initialization and readout. These results establish the Al1-center as a bright telecom-band
spin-
photon interface in silicon photonics and introduce a promising platform for integrated
quantum networks.
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All authors Carolina Crosta, Amirehsan Alizadehherfati, Purbita Purkayastha, Kyu-Young Kim, Jasvith Raj Basani, Chang-Min Lee, Fabio Pezzoli, Edo Waks
Chaotic Dynamics · Cross-listed from q-bio.PE
Gravity-Driven Eco-Epidemiological Dynamics in Tri-Trophic Food Chains
Yuvrajsingh Pravinsingh Patil, Eckehard Schöll, Fakhteh Ghanbarnejad et al. (+1 more)
Ecological communities are shaped by the interplay between trophic interactions and infectious disease, yet how spatially mediated interactions influence disease-driven ecosystem dynamics remains poorly understood. Here, we develop a
gravity-based eco-epidemiological framework for a tri-trophic food chain in which trophic interaction depends on species abundances and effective interaction distance. The disease-free food chain system supports a stable coexistence
equilibrium, providing a baseline for investigating disease-induced ecological transitions. Introducing infection at the intermediate trophic level destabilizes this
equilibrium through a
Hopf bifurcation, leading to sustained oscillations, whereas infection at the top predator level results in a qualitatively different transition from persistence to extinction. By systematically varying the
gravity coupling strength, we show that
gravity-mediated trophic interactions regulate the thresholds separating these ecological regimes, while the trophic position of infection determines the nature of the transition. Together, these findings establish a unified framework for understanding how spatially mediated trophic interactions and infectious disease jointly govern ecosystem stability, providing new insights into disease-driven dynamics in ecological communities.
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All authors Yuvrajsingh Pravinsingh Patil, Eckehard Schöll, Fakhteh Ghanbarnejad, Chandrakala Meena
Adaptation and Self-Organizing Systems · Cross-listed from cs.LG
Intelligence from Learnable Novelty
Yanbo Zhang and Michael Levin
Intelligence appears under different names in different fields: as data compression in statistics and machine learning, as universal computation in dynamical systems, and as adaptive behavior in
agents. Each field carries its own objective, and the two most influential drives often fail in mirror image: novelty search, which seeks surprise, is transfixed by a noisy television screen, while the free-energy principle, which avoids surprise, is most content in a dark room. Both failures have a single cause: each objective treats as one quantity the surprise a learner can convert into knowledge and the surprise it never can. Here we show that the learnable part of that information, which we call learnable novelty, yields the seemingly disparate projections of intelligence, and we give a closed-form
estimator of it built on a cheap and differentiable reservoir computer. Used as a measure, with no supervision of any kind, the
estimator recovers decades of complexity classification, ranking the Turing-complete rule~110 highest among the elementary cellular automata. Used as an objective, its gradient carries a neural cellular automaton from simple dynamics into a regime of
solitons, the traveling, colliding structures by which rule~110 computes, as well as organizes the representation of an image encoder around the ten digit classes of MNIST, fully unsupervised: no label ever enters training. Handed to a reinforcement-learning
agent as an intrinsic reward, it supplies the exploration that task rewards lack, improving on the task baseline in nine of ten environments and collapsing in none. Complexity generation, abstraction, and exploration, ordinarily pursued with unrelated objectives in separate fields, thus emerge from ascent on one differentiable quantity, and the projections of intelligence gain a common quantitative footing.
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Instrumentation and Methods for Astrophysics
First results for second generation SiSeRO CCD devices
Abigail Y. Pan, Declan O'Neill, Kevan Donlon et al. (+18 more)
The Astro2020 Decadal recommended the development of a suite of next generation astronomical observatories spanning the X-ray to near-IR spectrum. These programs require fast, extremely low noise detectors to fulfill their science goals. To address this technology gap, Stanford X-ray Astronomy and Observational Cosmology (XOC) group, MIT Lincoln Laboratory (MIT-LL), and MIT Kavli Institute (MKI) are advancing Single electron Sensitive Read Out (SiSeRO), a multiband detector technology capable of achieving substantially sub-electron noise via Repetitive Non-Destructive Readout (RNDR). We present initial results for our second generation SiSeRO CCDs. We also discuss our test bed, including a readout electronics system capable of accommodating all second-generation SiSeRO CCD variants utilizing the XOC-designed Multi-Channel Readout Chip (MCRC) ASIC.
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All authors Abigail Y. Pan, Declan O'Neill, Kevan Donlon, Peter Orel, Sven Herrmann, Steven Allen, Marshall W. Bautz, Tanmoy Chattopadhyay, Michael Cooper, Catherine E. Grant, Jill Juneau, Chris Leitz, Beverly LaMarr, Eric D. Miller, Glenn Morris, Tonya L. Peshel, Artem Poliszczuk, Gregory Prigozhin, Ilya Prigozhin, Haley R. Stueber, Keith Warner
Optics
Aromatic molecular emitters in a hexagonal boron nitride stack
Tianyu Fang, Ricardo Gioia Alvarez, Babak Behjati et al. (+8 more)
Single polycyclic aromatic hydrocarbon molecules embedded in organic
matrices have proven to be an excellent family of narrow-linewidth
quantum emitters. Extending this host-guest setting to van der Waals materials offers the opportunity to combine the preeminent properties of molecular emitters with the access to the versatility of two-dimensional hetero-structures and devices. In this work, we incorporate perylene molecules into multi-layered hexagonal boron nitride stacks and observe gigahertz-narrow zero-
phonon-line transitions at cryogenic temperatures. We unambiguously verify the origins of
photon emission through vibronic spectra analysis. By combining hyperspectral localization measurements with
quantum chemistry calculations, we examine the insertion mechanisms of perylene molecules in the hexagonal boron nitride stacks, and conclude that pristine hBN layers tend to expel molecules from the sandwich, while extended morphological defects, hydroxyl groups and unpassivated boron and nitrogen atoms assist to stabilize molecular bindings to hBN. Our work provides valuable insight for future work to deterministically integrate narrow-linewidth molecular emitters into van der Waals devices.
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All authors Tianyu Fang, Ricardo Gioia Alvarez, Babak Behjati, Moritz Scharfstädt, Max Masuhr, Bo Deng, Noah Henseler, Andrea Bergschneider, Stefan Linden, Christian Schäfer, Daqing Wang
Materials Science
Long lived localized defect states in monolayer WSe$_2$: Optical Lifetime distribution and thermal evolution
Immanuel Thekkooden, Susmitha Jana, Mrinal Deka et al. (+2 more)
We carefully investigate the recombination dynamics of localized defect emission in monolayer WSe$_2$ on SiO$_2$/Si substrate using time-resolved photoluminescence over the temperature range of 4 K to 120 K. We observe two long-lived optical lifetimes, one few nanosecond and one hundreds of nanoseconds. PL decay profile of these long lived states is fit well by a power-law, and based on
laser fluence studies, the likely origin of the power-law is due to a distribution of life-times rather than many body interactions. Temperature-dependence of these rates shows that thermal detrapping governs these long-lived channels and we obtained a value of 60 meV for the characteristics energy in a Bose-Einstein model. We performed
spin-resolved density functional calculations for selenium vacancies, the most likely source of native defects, to elucidate on
spin- and momentum-forbidden pathways which are the likely origin of these long lifetimes. Such detailed understanding of long-lived defect states is crucial for
quantum and optoelectronic applications.
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All authors Immanuel Thekkooden, Susmitha Jana, Mrinal Deka, B.R.K. Nanda, V Praveen Bhallamudi
Strongly Correlated Electrons
Coherent Magnons Driven by Photomodulated Anisotropy in Altermagnetic MnTe
Dingbin Huang, Jonathon Kruppe, Resham Babu Regmi et al. (+3 more)
Manganese telluride ($\text{MnTe}$) has recently emerged as a prototypical $g$-wave altermagnet, providing an ideal platform to investigate the non-
equilibrium excitations of altermagnetic order. Here, we report simultaneous spatial mapping of the local
equilibrium orientation of the Néel vector, $\varphi_L(\mathbf{r})$, alongside the amplitude, $\Delta\varphi(\mathbf{r},t)$, and frequency, $\Omega(\mathbf{r})$, of photoexcited
spin waves. Based on these measurements, we place a remarkably low upper bound of $\approx 60~\mu\text{eV}$ (0.7 K) on the
spin-wave gap arising from intrinsic anisotropy. This exceptionally weak hexagonal anisotropy ($K_6$) renders the altermagnetic order highly susceptible to optical tuning, allowing coherent
spin waves to be driven by a photoinduced enhancement of $K_6$. Above a threshold pump fluence, our spatial maps reveal that this photomodulation manifests as a six-fold symmetric sawtooth dependence of $\Delta\varphi$ on $\varphi_L$ and a cycloid-like modulation of $\Omega$. Ultimately, the near-isotropy of the Néel vector in $\text{MnTe}$ enables optical and mechanical control over the orientation of
spin-splitting in the electronic band structure, offering new pathways for altermagnetic spintronics.
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All authors Dingbin Huang, Jonathon Kruppe, Resham Babu Regmi, Nirmal J. Ghimire, James Analytis, Joseph Orenstein
Materials Science
Electron escape probability in high-efficiency photocathodes measured by reverse-injection photovoltage
S. A. Rozhkov, D. A. Kustov, V. V. Bakin et al. (+4 more)
The characterization of electron transfer through the emitting surface is of crucial importance for optimizing existing and developing new photocathodes. Here we propose and develop a method for the direct determination of the electron escape probability in high-efficiency
semiconductor photocathodes. The proposed method is based on the variations in the surface photovoltage upon the injection of emitted photoelectrons back into a photocathode (“reverse injection"), which is induced by the polarity reversal of the external electric field. We demonstrate the method on p-GaN(Cs,O) photocathodes with negative effective electron affinity by measuring the
evolution of photoemission
quantum efficiency upon the reverse injection of emitted electrons.
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All authors S. A. Rozhkov, D. A. Kustov, V. V. Bakin, V. S. Khoroshilov, V. L. Alperovich, O. E. Tereshchenko, H. E. Scheibler
Instrumentation and Methods for Astrophysics
Nancy Grace Roman Space Telescope Wide Field Instrument: Bright Point Source Saturation Response and Persistence Properties from Thermal-Vacuum Testing
Dana R. Louie, Robert F. Wilson, Thomas Barclay et al. (+19 more)
The Nancy Grace Roman Space
Telescope's Wide Field Instrument (WFI) will observe hundreds of thousands of bright
stars across its Core Community Surveys, particularly in the dense
stellar fields of the
Galactic Bulge Time Domain Survey (GBTDS). Sources brighter than ~17th magnitude will saturate WFI detector pixels in typical survey exposures, with the brightest
stars deeply saturating large pixel regions and potentially producing persistence signals that may impact subsequent observations. Prior detector characterization did not explore the regime of deep point source saturation. To address this gap, we conducted a bright
star saturation test during WFI's second Thermal
Vacuum test campaign (TVAC2) at BAE Space & Mission Systems in Boulder, CO. Using the Stimulus of Ray Cones (SORC)
telescope simulator, we projected nine in-focus point sources through the F146 filter onto two Sensor Chip Assemblies (SCAs), with fluxes tuned to approximate
stellar magnitudes ranging from ~4 to ~18 in ~170 s exposures. We present analyses of the saturation response and persistence properties of these detectors. We find that the saturated region of a ~4 mag source grows to ~150 pixels in diameter after ~170 s of illumination, compared to ~15 pixels for a ~12 mag source. Pixels adjacent to the expanding saturation front exhibit pronounced non-linear behavior consistent with charge leakage from saturated neighbors. For persistence, we find that the median signal in the first post-illumination dark exposure is broadly consistent across source magnitudes spanning ~4 to ~17, and that persistence decays to detector background levels ($\lesssim$0.05 e$^{-}$ s$^{-1}$) within approximately 20 minutes, consistent with flat field persistence measurements from the same TVAC2 campaign. These pre-flight characterization results inform community understanding of WFI detector response to prepare for Roman science.
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All authors Dana R. Louie, Robert F. Wilson, Thomas Barclay, Joshua E. Schlieder, Nicholas Bond, Evan Bray, Mario Cabrera, Stephanie Cheung, Ami Choi, Analia Cillis, Nicholas Collins, Tyler D. Groff, Robert J. Hill, Jeffrey Kruk, Gregory Mosby, Jennie Paine, Bernard J. Rauscher, Timothy A. Reichard, Maxime Rizzo, Scott Rohrbach, Nicole Schanche, Eric R. Switzer
Atmospheric and Oceanic Physics
Hard conservation correctors can hide a degrading model when training autoregressive emulators
William E. Chapman, John Schreck and Yingkai Sha
AI weather and
climate emulators increasingly incorporate physical principles into their formulation. One approach is to apply hard correctors that modify network outputs so that global mass, water, or energy budgets close. Prior work introduced such training-time correctors in the CREDIT framework and reported reduced precipitation bias and improved stability. Motivated by those results, we fine-tuned a global atmosphere emulator with a water-budget corrector, using the corrected prediction in the supervised loss and evaluating through post-correction budget closure. By that measure, training appeared successful. Every delivered field closed the moisture budget to machine precision. However, raw precipitation developed a growing global low bias over 18 training epochs, while the required correction increased from about 2% to roughly 24%. The cause is a scale degeneracy. A uniform change in raw precipitation amplitude is offset by a compensating change in the correction factor, leaving the corrected field, and therefore the supervised loss, unchanged. This invariance removes the restoring force on raw precipitation amplitude, allowing other training pressures to drive drift. Two changes recovered stable behavior. We supervised the pre-correction prediction and penalized its raw budget imbalance, while the hard correction remained in place for the delivered field. The required correction returned to less than 1% within the next epoch. A controlled 2x2 ablation showed that the runaway occurred only when corrected-output supervision was combined with no imbalance penalty. Exact post-correction closure therefore says little about whether the raw model has learned the budget. When a corrector removes information from the loss, the raw fields and the applied correction need to be tracked.
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Astrophysics of Galaxies
The Next Generation Virgo Cluster Survey (NGVS). II. A Catalog of Galaxies in the Virgo Cluster
Laura Ferrarese, Patrick Cote, Lauren A. MacArthur et al. (+51 more)
The Next Generation Virgo Cluster Survey (NGVS) is a deep, high resolution imaging campaign that used the 1 deg$^2$ MegaCam instrument on the Canada-France-Hawaii
Telescope to carry out a comprehensive optical survey of the Virgo cluster, from its core to its virial radius. The NGVS covers a contiguous area of 104 deg$^2$ (8.63 Mpc$^2$ at the 16.5 Mpc distance of Virgo) in the $u^*$-,$g$-,$i$-, and $z$-band, with additional limited coverage in $r$. In this paper, we present the final catalog of Virgo
galaxies across the entire NGVS area. The catalog includes 3680
galaxies considered to be $bona~fide$ members of the cluster, spanning a factor of 2.5 million in luminosity, from $g = 8.42$ mag to $g = 24.41$ mag ($M_g = -22.67$ mag to $M_g = -6.68$ mag). With 2100 previously uncataloged
galaxies, the NGVS catalog augments the number of known Virgo members by a factor 2.3. The catalog is complete down to $g = 18.6$ mag ($M_g=-12.5$ mag, corresponding to a
stellar mass $M_* \sim 1.6\times10^7~M_{\odot}$ for an old
stellar population) and 50% complete at $g = 22.0$ mag ($M_g=-9.1$ mag, $M_* \sim 6.2\times10^5~M_{\odot}$), three magnitudes deeper than the venerable Virgo Cluster Catalog (VCC), which for over 40 years has served as the reference standard for Virgo. Photometric and structural parameters are derived for all NGVS
galaxies and presented in a series of tables, alongside
nuclear and morphological classification, as well as
stellar masses and, when available, radial velocities.
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All authors Laura Ferrarese, Patrick Cote, Lauren A. MacArthur, Joel C. Roediger, John P. Blakeslee, Michele Cantiello, Jean-Charles Cuillandre, Puragra Guhathakurta, Stephen Gwyn, Max M. Kurzner, Eric W. Peng, Matthew Santos, Eleanore B. Todd, Elisa Toloba, Pierre-Alain Duc, Patrick R. Durrell, Nicholas Fantin, Yuting Feng, Ariane Lancon, Sungsoon Lim, Chengze Liu, Deborah Lokhorst, Alessia Longobardi, Simona Mei, J. Christopher Mihos, Sanjaya Paudel, Thomas H. Puzia, Anand Raichoor, Ruben Sanchez-Janssen, Kaixiang Wang, Hongxin Zhang, Alessandro Boselli, Michael L. Balogh, Samuel Boissier, Eric Emsellem, J.J. Kavelaars, Alan W. McConnachie, Cameron R. Morgan, Chelsea Spengler, James E. Taylor, Matthew A. Taylor, Toby Brown, Sebastien Fabbro, Raphael Gavazzi, Hendrik Hildebrandt, Rashi Jain, Andres Jordan, Rory Smith, Solveig Thompson, Haruka Yoshino, Wim van Driel, Ludovic van Waerbeke, Tyrone E. Woods, Jade Yeung
High Energy Physics (Phenomenology)
The Plan B Model: $Z^{\prime}$ collider phenomenology and discovery prospects
Ben Allanach, Hannah Banks and Jon Butterworth
The Plan B Model was proposed by Allanach et al. (2023) and explains some gross features of the
fermion mass spectrum. It also affects the predictions of various observables involving the $b \rightarrow s$
quark-flavour transition. The model predicts a new TeV-scale $Z^{\prime}$ which decays into various different final states. We constrain the viable parameter space of the model by re-casting several LHC direct searches for the $Z^{\prime}$ in addition to using Contur to test the model against unfolded measurements of various differential cross sections that are predicted to be non-zero in the Standard Model. We delineate the regions of parameter space that are excluded by current LHC data, and estimate the projected reach of the high luminosity LHC.
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High Energy Physics (Theory)
Refined Vafa-Witten invariants for toric surfaces from supersymmetric localization in 5D gauge theory
Osama Khlaif, Boris Pioline and Alessandro Tanzini
We study the partition function of five-dimensional $\mathcal{N}=1$ $U(N)$ supersymmetric Yang-Mills (SYM) theory with an adjoint hypermultiplet of mass $m_{\rm adj}$ on a toric Kähler surface $S$ times a circle of radius $\boldsymbol{\beta}$. Extending earlier work in $\mathcal{N}=2^*$ SYM theory on $S$, and in pure $\mathcal{N}=1$ SYM on $S\times \mathbb{S}^1_{\boldsymbol{\beta}}$, we find that the path integral localizes to an integral along the Cartan
torus of the product of Nekrasov 5D partition functions for each affine patch. Restricting to the gauge group $U(2)$ for simplicity, the integrand has an infinite set of poles of degree at most $\chi(S)-2$. With a natural prescription for integrating around such poles, we find that the contributing poles are in one-to-one correspondence with the
torus-fixed points in the
moduli space of semi-stable torsion-free sheaves on $S$. Moreover, for non-even first Chern class, their contributions are independent of the equivariant parameters $\epsilon_1,\epsilon_2$ and add up to the $\chi_{y^2}$-genus of that
moduli space, where $y^2=e^{-\boldsymbol{\beta} m_{\rm adj}}$, and hence coincide with the refined Vafa-Witten invariants. For even Chern class, the partition function depends on the equivariant parameters $\epsilon_1,\epsilon_2$ as well as $y$, and its relation to rational, refined Vafa-Witten invariants remains unclear.
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Earth and Planetary Astrophysics
Precise Determination of the Metallicity and C/O of WASP-39~b From a Single JWST Instrument Mode with Phase-Resolved Cross-Correlation Retrievals
Arjun B. Savel, Eliza M.-R. Kempton, Erin M. May et al. (+4 more)
Measuring atmospheric
metallicities and C/O ratios is a key goal of JWST
exoplanet science, given their proposed link to
planet formation. Achieving this goal has previously been shown to require broad wavelength coverage ($\sim$1–5 $\mu$m), typically demanding multiple instrument modes to complete the molecular inventory. Here, we show that the multi-instrument requirement can be circumvented using phase-resolved cross-correlation
retrievals at native pixel resolution – an approach more typically applied to ground-based high-resolution spectroscopy. By applying this novel analysis technique to an archival single-mode transit of the hot Jupiter WASP-39~b obtained with NIRSpec/G395H, we detect and obtain bounded abundances for all of its major carbon- and oxygen-bearing molecules: H$_2$O ($\Delta \ln(Z) = 67$), CO ($\Delta \ln(Z) = 25$), CO$_2$ ($\Delta \ln(Z) = 475$), and SO$_2$ ($\Delta \ln(Z) = 10$). Notably, while standard
retrieval methods fail to detect CO in these same data ($\Delta \ln(Z) = 0.2$), our approach detects it decisively, confirming it as the dominant carbon carrier in WASP-39 b's atmosphere. From these abundances, we robustly derive a
metallicity of $\rm [(C + O) / H] = 1.2 \pm 0.2$ and a C/O ratio of $0.68^{+0.10}_{-0.14} $, generally consistent with previous multi-instrument analyses. In comparison, traditional
retrievals performed on the G395H data alone produce biased and inaccurate values of both parameters, driven primarily by the non-detection of CO as well as incomplete water band coverage. Our results establish phase-resolved cross-correlation
retrievals as a powerful tool for extracting maximum atmospheric information from existing and future JWST data sets.
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All authors Arjun B. Savel, Eliza M.-R. Kempton, Erin M. May, Matthew C. Nixon, Jegug Ih, Katherine A. Bennett, Joost P. Wardenier
Earth and Planetary Astrophysics
Characterizing Microlensing Planetary System OGLE-2014-BLG-0676L with High-Resolution Image Constrained Light Curve Modeling
Asahi Idei, Naoki Koshimoto, Daisuke Suzuki et al. (+12 more)
We present an analysis that incorporates high-resolution Keck adaptive optics (AO) imaging into microlensing light-curve modeling for the planetary microlensing event OGLE-2014-BLG-0676. Using Keck AO observations obtained 6.3 years after the event, we directly resolved the lens and source. The Keck images reveal a tension, in that the $K$-band source flux is $0.52 \pm 0.22$ magnitudes brighter than predicted by previously reported light-curve models. By incorporating the Keck imaging constraints into the light-curve modeling, we find a host
star mass of $M_{\rm host} = 0.60^{+0.17}_{-0.14}\,M_{\odot}$, a lens distance of $D_{\rm L} = 1.88^{+0.63}_{-0.35}$ kpc, a
planet mass of $m_{\rm p} = 3.11^{+1.11}_{-0.63}\,M_{\rm J}$, and a projected separation of $a_{\perp} = 2.04^{+0.44}_{-0.35}$ au and $a_{\perp} = 3.72^{+0.92}_{-0.72}$ au for the close and wide solution, respectively. These results demonstrate the power of combining high-angular-resolution imaging with microlensing light-curve modeling to mitigate potential systematic effects and modeling degeneracies, enabling robust determinations of the physical properties of microlensing planetary systems. The results presented here can be confirmed by future observations from the Roman's
Galactic Plane Survey.
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All authors Asahi Idei, Naoki Koshimoto, Daisuke Suzuki, Kansuke Nunota, David P. Bennett, Ian A. Bond, Jean-Philippe Beaulieu, Takahiro Sumi, Aparna Bhattacharya, Joshua W. Blackman, Ryusei Hamada, Tsutsumi Nagai, Takuto Tamaoki, Sean K. Terry, Aikaterini Vandorou
High Energy Physics (Theory)
(De)Coherence of a quantum system in an anti-de Sitter spacetime
Mandas Biswas and Anupam Mazumdar
In this paper, we study the coherence/decoherence of a
quantum harmonic oscillator in anti-de Sitter (AdS) spacetime by quantising the graviton in a curved background with a nontrivial boundary condition. In the
quantum-field-theory framework, we obtain a master equation by tracing away the gravitational field at the leading order in G and 1/omega^2, where omega is related to the trapped frequency of the harmonic oscillator. We will proceed with a semi-Markovian analysis to compute the Lindbladian equation and estimate the decoherence rate and selection rules at the leading order, which come in two kinds: one responsible for the local interaction between matter and graviton, and the other related to the AdS global
curvature. The latter determines the recoherence of the
quantum system for a certain choice of the trapped harmonic oscillator's frequency and the global
curvature. We also demonstrate that we recover the flat spacetime limit by taking appropriate approximations.
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High Energy Physics (Phenomenology)
Feynman Integrals Meet Second-Order Partial Differential Equations
Xiang Chen and Hantian Zhang
We propose a second-order partial differential equation method to solve multi-loop Feynman integrals as an
equilibrium problem. As a proof-of-concept demonstration, we perform a Galerkin discretization of the corresponding variational form and employ the finite element method to compute two-loop four-point Feynman integrals. This method can solve the integral over a broad region of multi-dimensional phase space once and for all. This work establishes a new connection between perturbative
quantum field theory and modern partial differential equation methods, with the potential to streamline a wide range of phenomenological applications.
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General Relativity and Quantum Cosmology
Extreme mass-ratio inspirals into Newtonian Proca stars
João Bernardo Silva and Richard Brito
Massive bosonic fields can form self-gravitating solitonic structures, which for vector fields are known as Proca
stars. For ultralight fields, these structures can describe the cores of dark matter
haloes surrounding the supermassive black holes at the center of
galaxies. It has been argued that future gravitational-wave detectors might be able to probe the properties of dark matter structures. However, most of the analyses considering ultralight dark matter have focused on massive scalar fields. In this work, we study how Proca
stars respond to a perturbing small object inspiralling in their interior, in the Newtonian limit. We consider both Newtonian spherically symmetric Proca
stars and the nonspherically symmetric ground-state solutions. We compute the total energy lost by the orbiting object and compare it to the case where the bosonic
star is composed of a scalar field. Our results show that, at the Newtonian level, the energy lost by the object in a Proca
star ground state is similar to that in its scalar field counterpart, with relative differences of at most $\sim 20\%$, while the maximum orbital energy loss rate in the ground-state configuration can be one to two orders of magnitude larger than in the spherically symmetric Proca
star, when a central parasitic black hole is present. Our work motivates the need to study extreme mass-ratio inspirals into Proca
stars using a fully relativistic setup, where differences between the Proca and scalar
boson star ground states are expected to become more significant.
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Quantum Physics
Reducing entanglement with a Hamiltonian derived Clifford transformation
James Brown, Erika Lloyd, Alexandre Fleury et al. (+2 more)
Recently (Physica Scripta, 100(10):105401, 2025), an
algorithm was introduced that deterministically generates a Clifford transformation from the
Qubit Coupled Cluster (QCC)
algorithm which we call Q-Cliff (QCC+Clifford). There, it was shown that Q-Cliff could be utilized to generate a hardware efficient version of the QCC ansatz. Here, we examine and refine these techniques and show that Q-Cliff can be utilized to generate efficient classical and
quantum approximations to the ground states of chemical systems. The
algorithm generates an efficient variational method that generally has accuracy between MP2 and CISD with $O(N^6)$. Furthermore, we show through DMRG calculations that the
entanglement between
qubits is reduced significantly and therefore the accuracy for a given bond dimension can be vastly improved (up to an order of magnitude). Finally, we refine the previously reported
algorithm to generate low-depth and CNOT efficient
circuits that can be optimized with a comparable number of energy evaluations to state-of-the-art VQE
algorithms. All these results show that this
Hamiltonian derived Clifford transformation should be a tool used for many classical and
quantum algorithms.
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All authors James Brown, Erika Lloyd, Alexandre Fleury, Tarini S Hardikar, Kenny Heitritter
Materials Science
Towards a universal model for spin-orbit coupled Wannier Hamiltonians
Alexander C. Tyner
While machine learning interatomic potentials (MLiPs) have matured to revolutionize material science, deep learning models for electronic structure are just beginning to emerge and restricted, almost exclusively, to non-orthogonal basis
Hamiltonians. We introduce G(Wa)NN, the first deep-learning model capable of generating the electronic
Hamiltonian of solid-state systems in an orthogonal Wannier basis. G(Wa)NN is trained on an unprecedented, diverse
dataset of more than 111K Wannier
Hamiltonians (150M+ hopping
matrices) spanning 69 elements. The combination of optimized inference and linear-scaling methods for orthogonal
Hamiltonians unlock transport simulations at massive scales (10K+ atoms). Crucially, the framework supports local finetuning, allowing users to adapt the base model to custom Wannier
Hamiltonian datasets. To seamlessly translate these predictions into physical observables, we introduce Tailwater, a Python package providing an API interface to G(Wa)NN alongside a high performance post-processing library. Tailwater enables automated projection of the predicted
Hamiltonian into an arbitrary low-energy subspace-directly mirroring familiar Wannier90 workflows-and includes a suite of Kernel
Polynomial Method (KPM) functions that exploit the orthogonal basis to achieve strict linear scaling for spectral observables. The Tailwater ecosystem, with the G(Wa)NN model at its core, aims to help bridge the gap between deep learning and macro-scale
quantum transport simulations.
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High Energy Physics (Theory)
Warped Numerical Calabi-Yau Metrics
Severin Lüst, Fabian Ruehle and Simon Schreyer
We compute numerical warped Type IIB flux backgrounds on Calabi-Yau threefolds following the construction of Giddings, Kachru, and Polchinski. Using physics-informed neural networks, we approximate all three ingredients required by the GKP setup: the
Ricci-flat Calabi-Yau metric, the harmonic (2,1)-forms representing the imaginary self-dual three-form flux, and the warp factor, which solves a sourced Poisson equation on the internal
manifold. We apply our pipeline to the Dwork family of quintics for two different flux
vacua, one near a conifold point and one away from it, the latter serving as a numerical cross-check. With these tools, we study the singular bulk problem, and find that for our
benchmark point close to the conifold, approximately 0.5 percent of the total Calabi-Yau volume sits in the throat, and the warp factor is an order of magnitude larger as compared to the bulk. We also introduce several improvements to techniques used for numerical studies of CY metrics and quantities derived from them that might be of interest independently of our application. These include an improved point sampling
algorithm that produces samples that are more uniform under the Calabi-Yau measure, a feature-engineered spectral network for the metric, multi-step physics-informed training, and a weighted Huber loss tailored to stiff PDEs with highly non-uniform sources.
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Quantum Physics
Monolithic printed-circuit board RF-trap for electrons
Zijue Luo, Jae Eu, Tianyi Wang et al. (+1 more)
Qubits encoded in the
spin of trapped electrons have been proposed as a promising novel platform for
quantum information processing. While trapping of electrons has been largely carried out in Penning traps for precision measurement purposes, it is desirable to use linear Paul traps instead, leaning on the successes of trapped ion
quantum processors. Here we present a Paul trap for electrons made of a single printed
circuit board. Our approach requires no assembly and the rigid design minimizes manufacturing intolerances. We characterize the trap performance and observe trapped electron lifetimes of 2.13 ms and secular frequencies of up to 90 MHz.
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All authors Zijue Luo, Jae Eu, Tianyi Wang, Boerge Hemmerling
Quantum Physics
Magic-protected entanglement and Clifford-irreducible structure in magic state space
Alejandro Borda Kuhlmann and Julian Rincon
We develop a Clifford-orbit framework for studying magic-protected
entanglement, which we refer to as magical
entanglement: the part of bipartite
entanglement that remains after optimal stabilizer simplification. This construction leverages residual
entanglement under Clifford reduction as a state-level organizing principle for magic state space. It defines canonical representatives, spectra, and ranks that characterize the Clifford-irreducible structure of a state. We identify two regimes of the magic-
entanglement interplay. In the $T$-magic regime, local nonstabilizer resources can coexist with
entanglement, but the protected component remains weak and state-dependent. In the $W$-magic regime, by contrast,
entanglement is Clifford-irreducibly tied to nonstabilizerness, producing typical, strongly self-averaging behavior. Analytical examples and random-
circuit numerics support a crossover from broad $T$-magic fluctuations to concentrated, Haar-like $W$-magic behavior. These results identify magical
entanglement as an orbit-level diagnostic of how nonstabilizerness protects
quantum correlations against Clifford reduction.
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General Relativity and Quantum Cosmology
Nonradial perturbations of static charged wormholes
Jose Luis Blázquez-Salcedo, Luis Manuel González-Romero, Fech Scen Khoo et al. (+2 more)
We investigate the nonradial quasinormal-mode spectrum of static charged Ellis–Bronnikov wormholes in Einstein–Maxwell theory minimally coupled to a phantom scalar field. The background solutions are known in closed form and comprise three classes: subcritical, critical and supercritical, which all approach the extremal Reissner–Nordström geometry at the boundary of their domain of existence. We derive the linear perturbation equations for axial and polar sectors, including the coupled gravitational, electromagnetic and phantom-scalar degrees of freedom, and compute the corresponding spectra by means of a Chebyshev spectral method. The uncharged limit reproduces the known Ellis–Bronnikov spectrum and exhibits the expected electromagnetic isospectrality. For charged configurations we track the axial and polar branches across the three families of solutions and identify the effect of the charge on the damping times and oscillation frequencies. In particular, we find that charge can substantially reduce damping rates as the extremal Reissner–Nordström limit is approached. We also uncover a nonradial polar instability, most clearly visible in the fundamental $l=2$ branch for sufficiently large wormhole masses. This instability is distinct from the familiar radial Ellis–Bronnikov instability and shows that the nonradial sector imposes additional constraints on the dynamical viability of charged wormholes.
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All authors Jose Luis Blázquez-Salcedo, Luis Manuel González-Romero, Fech Scen Khoo, Jutta Kunz, Pablo Navarro Moreno
High Energy Physics (Theory)
The fermion sector of the SMEFT from asymptotically safe gravity
Astrid Eichhorn, Moritz Gessner and Shouryya Ray
Quantum gravity impacts Standard Model fields through effective interactions generated by renormalization. These appear as Standard Model Effective Field Theory (SMEFT) operators, where the effects of new physics are parametrized by the values of the higher-order SMEFT coefficients. As a step towards predicting these SMEFT coefficients from the asymptotically safe Standard Model with
quantum gravity, we investigate the flow of a representative set of four-
fermion operators under gravitational fluctuations. We strengthen the evidence for the near-perturbative nature of asymptotic safety by finding that these dimension-six-interactions remain irrelevant, resulting in the prediction of specific values for the dimensionless ratios of SMEFT coefficients in the IR. We also find a mechanism that can make a specific subset of these operators relevant. This subset is determined by
symmetry considerations. On this basis, we provide a categorization of dimension-six-SMEFT interactions into two categories. Interactions in the first category are predicted to be non-zero, but Planck-scale suppressed. Interactions in the second category are predicted to be zero at small gravitational coupling, but may become free parameters of the theory at larger gravitational couplings.
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