Papers

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Physics

Saturday 8 August

General Relativity and Quantum Cosmology

Causal-diamond thermalization induces nonseparability in N-partite quantum systems

Hui-Chen Yang and Shu-Min Wu

We investigate the nonseparability of multipartite bosonic and fermionic $GHZ$ and $W$ states in a causal diamond spacetime using the Abe-Rajagopal (AR) $q$-conditional entropy. The finite lifetime of the observer gives rise to a causal diamond horizon, which induces an Unruh-like thermal effect and leads to a nontrivial restructuring of nonseparability in $N$-partite systems. Our main result is that the thermal effect can enhance a net nonseparability of fermionic $W$ states, in sharp contrast to the general expectation that relativistic thermalization leads to a monotonic degradation of bosonic nonseparability. In addition, we find that fermionic nonseparability is generally more robust than its bosonic counterpart under causal diamond restrictions. Among different entangled resources, $GHZ$ states exhibit stronger nonseparability and greater robustness than $W$ states under identical causal conditions. We further show that the nonseparability of $W$ states decreases with increasing particle number $N$, whereas that of $GHZ$ states remains independent of $N$ in causal diamond spacetime. These results demonstrate that particle statistics, entanglement structure, and observer lifetime jointly determine the persistence of nonseparability in causally restricted spacetimes, providing insights for relativistic quantum information processing.

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Optics

Sub-Rayleigh Imaging of Unequal-Intensity Sources: Near-Quantum-Limit Multiparameter Estimation

Y. Batuhan Yilmaz, Kent A. G. Bonsma-Fisher, Muhammad Mohid et al. (+3 more)

In optical imaging, diffraction strongly degrades the performance of conventional intensity-based estimation once the separation between two sources is below the Rayleigh-Abbe limit. Recent developments showed that this limitation can be surpassed using spatial-mode demultiplexing (SPADE), and this was demonstrated in several experiments for two equal-intensity spots of unknown separation. When there are multiple unknown parameters, as in the case of several unequal sources with unknown intensities and unknown separation, cross-talk among the parameters makes the multi-parameter estimation problem significantly more challenging. In this paper, we adapt super-resolved position localization by inversion of coherence along an edge (SPLICE) to estimate both the separation and relative intensity of two incoherent sources simultaneously. We demonstrate a clear advantage over direct imaging (DI), achieving a root mean squared error (RMSE) approximately $50 \%$ larger than the quantum limit and a sixfold improvement over DI within the range of parameters we tested. This improvement can be even greater for smaller separations and larger intensity imbalances when crosstalk is suppressed.

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All authors Y. Batuhan Yilmaz, Kent A. G. Bonsma-Fisher, Muhammad Mohid, Noah Lupu-Gladstein, Arthur O. T. Pang, Aephraim M. Steinberg

Instrumentation and Detectors

Performance of an HRPPD in Tesla-scale magnetic fields

B. Azmoun, Y. Ilieva, Y. Jin et al. (+9 more)

High-Rate Picosecond Photodetectors (HRPPDs) are state-of-the-art microchannel-plate (MCP) photodetectors that offer excellent timing and spatial resolution, together with high single-photon detection efficiency. They are currently being considered for the ePIC experiment at the future Electron Ion Collider (EIC) at Brookhaven National Laboratory. A key requirement for the application of this technology is reliable operation in a strong magnetic field up to 1.5 T, with magnetic flux lines at an inclination of $\le15^\circ$ to the normal of the MCP surface. Magnetic field-induced distortions of the collected charge in MCP-based detectors can be compensated by tuning the operating parameters; however, the objective of this study is to quantify this performance in the case of the EIC-HRPPD, a particular MCP stack-up specialized for operation within ePIC. This photosensor employs a high quantum efficiency photocathode, 10$~\mu$m capillary pores, narrow transfer gaps, and a custom ceramic pixelated DC-coupled readout. This article explores the optimal operating parameters (mainly the voltages applied across the gaps and the MCPs) for single photon detection at various inclination angles in a uniform field up to 1.8 T. Ultimately, it was found that the gain and single photon detection efficiency of the HRPPD could be recovered over a range of polar inclination angles up to $\pm35^\circ$.

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All authors B. Azmoun, Y. Ilieva, Y. Jin, J. Kim, A. Kiselev, B.S. Page, M. Popecki, M.L. Purschke, A. Tamis, V. Teotia, C.P. Wong, C. Woody

Materials Science

Spin selective non-van der Waal electride nature in manganese under ambient pressure

Shishir Timilsena, Dinesh Thapa, David James Faller et al. (+3 more)

Electrides are an unusual class of ionic materials in which electrons localized in non-nuclear, interstitial regions act as anions within the crystal lattice. Here, we employ first-principles quantum mechanical calculations to investigate the structural, electronic, magnetic, and electride characteristics of elemental manganese (Mn) at an ambient pressure (0 GPa), focusing on its three crystalline phases: cubic ($\alpha$)-Mn ($I\bar{4}3m,no.217$), cubic ($\beta$)-Mn ($P4_132, no.213$), and hexagonal ($hex$)-Mn ($P6_3/mmc, no.194$). Our calculations reveal pronounced interstitial-electron character in all three phases, accompanied by spin-selective electron localization function (ELF), establishing elemental Mn as a non-van der Waals electride system. Bader charge analysis indicates substantial electron redistribution from the Mn host framework toward the interstitial anionic-electron (IAE) regions, with an effective charge transfer of approximately $-1.645e$, $-1.477e$, and $-1.083e$ per interstitial basin in $\alpha$-Mn, $\beta$-Mn, and $hex$-Mn, respectively. The electride character is further supported by the electronic density of states, where the IAE-associated states exhibit finite contributions near the Fermi level ($E_F$) and coexist with Mn-derived states, demonstrating their direct participation in the low-energy electronic structure. The combined electron localization function (ELF), effective charge transfer, and electron population due to IAE at $E_F$ therefore provide consistent evidence for interstitial anionic electrons in elemental Mn. To the best of our knowledge, this work provides the first systematic identification of spin-selective electride character in elemental Mn at ambient pressure, highlighting the possibility of exploiting its interstitial-electron states for unconventional electronic and magnetic functionalities.

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All authors Shishir Timilsena, Dinesh Thapa, David James Faller, Prabesh Adhikari, Nicholas Dimakis, Svetlana Kilina

High Energy Astrophysical Phenomena

Anisotropic Particle Transport from a Pulsar Wind Nebula Revealed by Einstein Probe and LHAASO

Zhen Cao, F. Aharonian, Y.X. Bai et al. (+342 more)

Pulsar wind nebulae (PWNe) are major cosmic ray accelerators, yet the mechanisms transporting high-energy particles into the interstellar medium remain elusive. Building on the LHAASO discovery of an ultra-high-energy (UHE) $\gamma$-ray source near the bow-shock PWN powered by the pulsar PSR J1740+1000, we present a joint Einstein Probe (EP) and LHAASO study of this system. EP observations reveal an extended X-ray tail far exceeding the structure previously seen by XMM-Newton. Updated LHAASO observations show that the $\gamma$-ray emission is elongated, with its major axis aligned with the extended X-ray tail revealed by EP. This is the first detection of an X-ray pulsar tail associated with a spatially coincident extended UHE $\gamma$-ray emission. The X-ray and $\gamma$-ray spectrum can be well explained with a single population of relativistic electrons via synchrotron and inverse Compton radiation, respectively, removing the need for particle re-acceleration during propagation. The results unambiguously show that electrons/positrons above 100 TeV are escaping from the PWN. Instead of the immediate, isotropic diffusion into ambient interstellar medium that is typically assumed, these particles are transported anisotropically over at least $\sim$10 pc, either guided by the background magnetic field or carried by an advective outflow.

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All authors Zhen Cao, F. Aharonian, Y.X. Bai, Y.W. Bao, D. Bastieri, X.J. Bi, Y.J. Bi, W. Bian, J. Blunier, A.V. Bukevich, C.M. Cai, W.Y. Cao, Zhe Cao, J. Chang, J.F. Chang, E.S. Chen, G.H. Chen, H.K. Chen, L.F. Chen, Liang Chen, Long Chen, M.J. Chen, M.L. Chen, Q.H. Chen, S. Chen, S.H. Chen, S.Z. Chen, T.L. Chen, X.B. Chen, X.J. Chen, X.P. Chen, Yang Chen, Yong Chen, N. Cheng, Q.Y. Cheng, Y.D. Cheng, Y.H. Chi, M.Y. Cui, S.W. Cui, X.H. Cui, Y.D. Cui, B.Z. Dai, H.L. Dai, L.X. Dai, Z.G. Dai, Danzengluobu, Y.X. Diao, A.J. Dong, X.D. Duan, J.H. Fan, Y.Z. Fan, J. Fang, J.H. Fang, K. Fang, C.F. Feng, H. Feng, L. Feng, S.H. Feng, X.T. Feng, Y. Feng, Y.L. Feng, S. Gabici, B. Gao, Q. Gao, W. Gao, C. Ge, M.M. Ge, T.T. Ge, L.S. Geng, G. Giacinti, G.H. Gong, Q.B. Gou, M.H. Gu, W.M. Gu, F.L. Guo, J. Guo, K.J. Guo, X.L. Guo, Y.Q. Guo, R.P. Han, O.A. Hannuksela, M. Hasan, H.H. He, H.N. He, J.Y. He, X.Y. He, Y. He, S. Hernández-Cadena, C. Hou, X. Hou, H.B. Hu, S.C. Hu, D.H. Huang, F. Huang, J.J. Huang, X.L. Huang, X.T. Huang, X.Y. Huang, Y. Huang, Z.J. Huang, A. Inventar, X.L. Ji, H.Y. Jia, K. Jia, S.M. Jia, H.B. Jiang, K. Jiang, X.W. Jiang, Z.J. Jiang, C.C. Jin, M. Jin, S. Kaci, M.M. Kang, I. Karpikov, D. Khangulyan, D. Kuleshov, K. Kurinov, W.H. Lei, Cheng Li, C.K. Li, Cong Li, D. Li, F. Li, H.B. Li, H.C. Li, Jian Li, Jie Li, K. Li, L. Li, R.L. Li, T.Y. Li, W.L. Li, X.R. Li, X.Y. Li, Y. Li, Zhe Li, Zhuo Li, E.W. Liang, Y.F. Liang, S.J. Lin, B. Liu, C. Liu, D. Liu, D.B. Liu, H. Liu, J. Liu, J.L. Liu, J.R. Liu, M.Y. Liu, Q. Liu, R.Y. Liu, S.M. Liu, T. Liu, W. Liu, Y. Liu, Y. Liu, Yuan Liu, Y.N. Liu, Y.Q. Lou, Q. Luo, Y. Luo, H.K. Lv, B.Q. Ma, L.L. Ma, X.H. Ma, I.O. Maliy, J.R. Mao, Z. Min, W. Mitthumsiri, Y. Mizuno, G.B. Mou, A. Neronov, C.-Y. Ng, K.C.Y. Ng, M.Y. Ni, L. Nie, L.J. Ou, Z.W. Ou, H.W. Pan, P. Pattarakijwanich, Z.Y. Pei, D.Y. Peng, J.C. Qi, M.Y. Qi, J.J. Qin, H. Qu, A. Raza, C.Y. Ren, M.Q. Ruan, D. Ruffolo, A. Sáiz, D. Savchenko, D. Semikoz, L. Shao, O. Shchegolev, Y.Z. Shen, X.D. Sheng, F.W. Shu, H.C. Song, Yu.V. Stenkin, Y. Su, C.Y. Sun, D.X. Sun, H. Sun, J.X. Sun, M. Sun, Q.N. Sun, X.N. Sun, Z.B. Sun, N.H. Tabasam, J. Takata, P.H.T. Tam, H.B. Tan, Q.W. Tang, R. Tang, Z.B. Tang, L. Tao, W.W. Tian, C.N. Tong, L.H. Wan, C. Wang, D.H. Wang, G.W. Wang, H.G. Wang, J.C. Wang, J.F. Wang, J.S. Wang, K. Wang, Kai Wang, Kai Wang, L.P. Wang, L.Y. Wang, W. Wang, X.G. Wang, X.J. Wang, X.Y. Wang, Y. Wang, Y.D. Wang, Z.H. Wang, Z.X. Wang, Zheng Wang, D.M. Wei, J.J. Wei, Y.J. Wei, T. Wen, S.S. Weng, C.Y. Wu, H.R. Wu, Q.W. Wu, S. Wu, X.F. Wu, Y.S. Wu, S.Q. Xi, J. Xia, G.M. Xiang, D.X. Xiao, G. Xiao, Y.F. Xiao, B.H. Xie, F. Xie, Y.L. Xin, H.D. Xing, Y. Xing, D.R. Xiong, B.N. Xu, C.Y. Xu, D.L. Xu, R.X. Xu, S.S. Xu, L. Xue, D.H. Yan, T. Yan, C. Yang, C.Y. Yang, F.F. Yang, L.L. Yang, M.J. Yang, R.Z. Yang, W.X. Yang, Z.H. Yang, Z.G. Yao, X.A. Ye, L.Q. Yin, N. Yin, X.H. You, Z.Y. You, Y.H. Yu, Q. Yuan, W.M. Yuan, H. Yue, H.D. Zeng, T.X. Zeng, W. Zeng, X.T. Zeng, M. Zha, B. Zhang, B.B. Zhang, B.T. Zhang, C. Zhang, H. Zhang, H.M. Zhang, H.Y. Zhang, J. Zhang, J.L. Zhang, J.Y. Zhang, L.Y. Zhang, Li Zhang, P.F. Zhang, R. Zhang, R.Y. Zhang, S.R. Zhang, S.S. Zhang, S.Y. Zhang, W. Zhang, X. Zhang, X.L. Zhang, X.P. Zhang, Yi Zhang, Yong Zhang, Z.P. Zhang, H.S. Zhao, J. Zhao, L. Zhao, L.Z. Zhao, X.H. Zhao, F. Zheng, T.C. Zheng, B. Zhou, H. Zhou, J.N. Zhou, L. Zhou, M. Zhou, P. Zhou, R. Zhou, X.X. Zhou, X.X. Zhou, B.Y. Zhu, C.G. Zhu, F.R. Zhu, H. Zhu, K.J. Zhu, Y.F. Zhu, Z.F. Zhu, Y.C. Zou, X. Zuo

Quantum Gases

Coherent Control of Domain-Wall Transport in an Ultracold Bose Gas

O. Farion, M. Pourzand and J. M. McGuirk

Domain walls are carriers of spin transport whose controlled manipulation underlies a wide range of spintronic and information-processing technologies. Here we demonstrate tunable domain-wall transport in a weakly interacting nondegenerate ultracold Bose gas. We initialize a three-domain pseudo-spin-1/2 texture and observe spontaneous propagation of long-lived domain walls driven by exchange-mediated spin currents. By varying the orientation of the spin domains, we control the balance of spin currents across the walls and thereby tune their trajectories, including reversals of the initial direction of motion. Measurements reveal a crossover from an exchange-stabilized regime, in which coherent spin-exchange collisions suppress wall motion, to a diffusion-dominated regime characterized by rapid transport at thermal velocities. Numerical solutions of a quantum Boltzmann equation reproduce the observed dynamics and identify transverse phase gradients as an important control parameter governing domain-wall propagation. These results establish coherence and phase engineering as tools for programming spin transport in ultracold gases and provide a route toward controllable domain-wall dynamics in atomtronic systems.

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Quantum Physics

Playing Nonlocal Games with Little to No Shared Randomness

Mingze Xu and Eric Chitambar

Bell nonlocality reveals correlations that cannot be explained by classical models and plays a central role in quantum information theory. In this work, we investigate classical models of Bell nonlocality under restrictions on shared randomness. For bipartite scenarios with bounded shared randomness, the set of classical correlations becomes nonconvex. We characterize the correlations achievable without shared randomness through the simultaneous evaluation of multiple linear Bell functionals. We then extend our analysis to quantum networks by relaxing the standard assumption of source independence. In this setting, the feasibility constraints derived for the bipartite case can be used to certify source dependence, and we further construct nonlinear inequalities that distinguish classical models with correlated sources from correlations achievable in standard quantum networks. As an application, we show that these nonlinear network inequalities give rise to an entropic Bell inequality for bipartite scenarios with limited shared randomness.

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Solar and Stellar Astrophysics

NATA: a chemical-picture equation of state for stellar merger hydrodynamics

Natalia Ivanova

We present NATA (Nearly Always Truthful Approximations), a self-contained chemical-picture equation of state for hydrogen-helium-carbon-oxygen mixtures, developed for hydrodynamics calculations of stellar mergers and common envelope evolution. NATA carries bound species explicitly in ionisation and dissociation equilibrium and evaluates pressure, internal energy, and entropy from one continuous, single-physics chemical-picture solve built on analytic and semi-analytic component physics, rather than by stitching together component EOS tables. The result is smooth thermodynamics across ionisation, dissociation, and degeneracy fronts, with monotonic internal energy and no artificial energy steps at EOS seams, so the EOS inverts cleanly for codes that advance internal energy. We benchmark NATA against the blended MESA EOS, ab initio hydrogen-helium tables, and reference-independent analytic limits. NATA reproduces clean analytic limits and selected fully ionised benchmarks at the sub-percent level, while most remaining percent-level residuals are confined to partial-ionisation and dissociation fronts; these residuals are traced to identifiable picture choices, front placements, and reference-table seams or extrapolations. NATA therefore provides a well-behaved fallback in cool, low-density regimes where blended EOS tables may be stretched beyond their intended use and become physically unreliable.

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Friday 7 August

Quantum Physics

Predictive Holonomy and Minimal Completion of Coarse Dynamics

Maxim V. Churilov

A coarse description of a dynamical system generally fails to evolve autonomously: evolving and coarse-graining in different orders gives different predictions, and the compressed propagator fails the semigroup law. We show that this path dependence is the observable boundary of missing state. For a finite continuous-time Markov chain with generator $L$, coarse channel $C$, and stochastic section $R$ satisfying $CR=I$, define $P=RC$, $Q=I-P$, and $K=CLR$. The exact coarse propagator $T_t=C\mathrm{e}^{tL}R$ obeys a Volterra equation with memory kernel $\mathcal{M}(t)=CLQ\,\mathrm{e}^{tQLQ}\,QLR$. Every memory jet $\mathcal{M}^{(k)}(0)$ is recursively recoverable from the short-time derivatives of $T_t$ alone. The rank of the block Hankel operator $\mathbb{H}_{\infty}=(\mathcal{M}^{(i+j)}(0))_{i,j\geq 0}$ is exactly the smallest number of auxiliary linear state variables required to turn the coarse dynamics into an exact autonomous, time-homogeneous system. A minimal completion is constructible by Ho–Kalman factorization and is unique up to similarity. If $d=\min\{k:\mathcal{M}^{(k)}(0)\neq 0\}$, then every smooth classical $f$-divergence generically scales as $t^{2d+4}$. Exact Markov examples realize exponents $4,6,8$ and closure ranks $1,2,3$. We also derive finite-sample singular-value certificates for hidden predictive coordinates, including a matrix-Bernstein bound with intrinsic-variance control. Finally, histories are identified when they induce the same future law under every admissible intervention, yielding the minimal counterfactual predictive state. The results turn coarse-graining into a constructive state-completion problem and separate ordinary linear realization from the harder requirement of a positive or Markov realization.

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Instrumentation and Methods for Astrophysics

Partial-field inferability of galaxy overdensity structure: An information-geometric account of incomplete sky coverage

Marko Imbrišak and Krešimir Tisanić

Structural statistics of the galaxy distribution are routinely measured on only partially observed fields, yet how much structure survives incomplete coverage, and which aspects are lost first, is rarely quantified independently of the statistic being reported. We cast this as inference on a fixed structure vector Theta=(Delta_Omega, f_HD, L_HD): a global density contrast, a high-density fraction, and the connected extent of the high-density set. Densities are assigned to galaxies through their Voronoi cell areas, with connectivity on the dual Delaunay graph. Two mechanisms generate subsets, spatially correlated random-walk coverage and spatially uncorrelated node loss, and recovery is measured with a Fisher-inspired reference metric held fixed across coverage levels, mechanisms and estimators. Applied to a z-sliced COSMOS field of 94043 galaxies, the three components form a strict hierarchy: the connected extent is recovered several times less accurately than the scalar amplitudes at every incomplete coverage, by a margin that widens as coverage improves, and is the last to converge. The two mechanisms trade off in opposite directions, uniform loss preserving the amplitudes and walk coverage the morphology, so inferability depends not only on how much of the field is observed but on how it is observed. A joint single-number criterion can order the mechanisms but is tolerance dependent and can reverse, whereas the component-level contrast is metric-independent and robust; the degree-based inverse-probability weight, though natural for random-walk sampling, is inconsistent for set-valued coverage. Partial-field structure statistics therefore degrade anisotropically in information space, and a single coverage fraction is insufficient to characterise what a partially observed field can support.

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Instrumentation and Detectors

Super-Lindhard Ionization from 254 eVnr Nuclear Recoils in Germanium

A.R.L. Kavner, E. Todd, M. Babicz et al. (+11 more)

We report ionization produced by the stopping of monoenergetic 254 eVnr 73Ge ions within a germanium lattice which exceeds the Lindhard prediction. The observed deviation is based upon prior measurements of the ionization produced by monoenergetic 254 eVnr Ge nuclear recoils and newly performed systematic studies of relevant nuclear physics processes. Combined with our prior work, the incompatibility with the Lindhard prediction increases to the 4.5 sigma level. We employ an empirical excess ionization model that exhibits super-Lindhard ionization from sub-keV nuclear recoils and converges back to the Lindhard model for higher energy recoils, above 1 keVnr. The excess ionization model is preferred over a pure Lindhard model when fit to the literature of germanium quenching factor data.

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All authors A.R.L. Kavner, E. Todd, M. Babicz, H. Birch, K. Dwinger, A. Fazan, V. Fondement, M. Janoschek, I. Jovanovic, L. Juigne, K. Moraa, B. Penning, F. Piastra, F. Uwe

Applied Physics

Slow dynamics in concrete: Effects of temperature, strength variation, and microcracking damage

Clayton Malone and Jinying Zhu

In this study, we investigated the slow dynamic behavior of concrete with varying compressive strengths ($f'_c = 32\sim56$ MPa) and alkali-silica reaction (ASR) damage. Concrete prisms were conditioned by compressive loading and recovery was monitored by coda wave interferometry (CWI). A self-referencing temperature correction technique was used to minimize the effect of ambient temperature changes, demonstrating the importance of careful temperature control and correction. For intact specimens, both the recovery rate, $m_v$, and velocity drop magnitude, $|c|$, generally increased with compressive strength. Recovery times were calculated from the fit parameters, and higher strength specimens were found to recover faster (9.9 h for $f'_c = 32$ MPa, 6.6 h for $f'_c = 56$ MPa). When the same stress was applied, ASR-damaged specimens had increased softening and faster recovery rates, but longer recovery times (up to 458 h). These findings demonstrate the potential of slow dynamics in concrete characterization, through its ability to evaluate the strength of intact samples and its sensitivity to microcracking in damaged samples.

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General Physics

Optical-Fiber Activation of Observer-Split Source Terms in a Rotating Aluminum Disc

Antonio Iadicicco and Luigi Verolino

We propose an optical-fiber implementation of the Observer-Split source framework for finite rotating systems in extended Aharonov-Bohm electrodynamics. A covariantly conserved current, rewritten in a rotating 3+1 split, produces the observer-adapted source term $I_{\rm split}=N^{-1}D_i(\rho\beta^i)$, which in the weak-field rigid-rotation limit becomes $I_G=\Omega\partial_\phi\rho$. We use an optically gated rotating aluminum disc to create a localized, calibratable induced density, with the optical evanescent/tunneling coefficient acting only as a control gate rather than as a charge density. The resulting source scales as $I_{\rm opt}\simeq\Omega\partial_\phi\rho_{\rm ind,Al}$ and reverses sign under CW/CCW reversal. The proposed demonstrator combines ON/OFF gating, a localized 10–20 degree active sector, uniform-source suppression, material and dummy controls, quantitative null bounds, and independent density calibration. The residual response is parameterized by the experimentally identifiable product $\Lambda_{\rm opt}=\kappa_{\rm opt}\chi_{\rm Al}$, so both positive and null measurements constrain the phenomenology without assuming an uncalibrated force amplitude. Historical rotating magnetic systems, including the Roshchin-Godin report, are used only as benchmarks and not as evidence. The work is a falsifiable protocol for testing anomalous gravitational-response signatures; it reports no anomalous-weight measurement and makes no claim of evidence for a gravitational anomaly or for extended Aharonov-Bohm electrodynamics.

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High Energy Physics (Phenomenology)

Effective propagators of flavor neutrinos

Maxim Dvornikov

We analyze the possibility to construct propagators of flavor neutrinos, which are particles with indefinite masses. This kind of propagators was used previously while studying neutrino flavor oscillations in frames of the quantum field theory (QFT) based approach. Starting with the operator and the path integral formulations of the QFT, we obtain that the naive derivation of propagators for flavor neutrinos violates the basic principles of the QFT. Nevertheless, we can still construct the effective propagator of flavor neutrinos considering the mass mixing term as a perturbation. In this situation, the effective propagator arises from the solution of a Dyson-like equation. We use the derived effective propagator to rederive the quantum mechanical transition probability for neutrino oscillations in vacuum in frames of the QFT. The application of the obtained results to neutrino oscillations in background matter is also considered.

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Quantum Physics · Cross-listed from cs.LG

The Quantum Shortcut: Complex Phase-State Dynamics Reduce the Optimization Steps of Sequence Models

Ahmed Nebli, Hadi Saadatdoorabi, Christopher Keibel et al. (+1 more)

Sequence models are conventionally distinguished by their backbone, the mechanism that routes information across positions, such as attention or recurrence. This paper varies a choice that is prior to the backbone and shared by nearly all current models: the substrate, the number system in which the hidden state is represented together with the form of the map from state to prediction. The prevailing substrate is a real-valued state with an affine–softmax readout; we study a complex-valued alternative drawn from the mathematics of quantum theory, in which information is carried by the phases of the state and scores are quadratic Born forms. Prior work proved an idealized version of this substrate representationally stronger than any real model with a linear readout; we ask whether it also trains faster. Relaxing the two properties that block deployment, exact unitarity and the Born vocabulary readout, we instantiate it in the Mamba state-space model and an attention-based Transformer. At 253M parameters, matched to within $0.02\%$ and trained under one fixed protocol on three byte-level corpora, the complex models reach every measured validation loss in approximately one third (state-space) and one half (attention) of the optimization steps of their real counterparts. The two backbones then diverge. Once the learning-rate warmup ends, the state-space advantage continues to widen, from $0.321$ to $0.354$ bits per character on OpenWebText and from $0.368$ to $0.396$ on FineWeb, which an artifact of the warmup ramp would not do; the attention advantage instead decays toward zero on every corpus, and is therefore an effect of early training.

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All authors Ahmed Nebli, Hadi Saadatdoorabi, Christopher Keibel, Kevin Yam

High Energy Physics (Theory)

Casimir Force in Spacetimes with Torsion

M.W. AlMasri

We compute the Casimir force between perfectly conducting parallel plates in a spacetime endowed with constant axial torsion. Working within an effective field theory framework where torsion couples to the electromagnetic sector via a gauge-invariant Chern–Simons-type interaction, we derive the modified photon dispersion relation and mode spectrum. Using zeta-function regularization, we obtain the vacuum energy and the resulting Casimir pressure to second order in the torsion parameter. Our calculation yields a correction scaling as $\Delta P/P_0 = -\frac{5\xi^2 S_z^2 a^2}{4\pi^2} + \order(S_z^4)$, which corresponds to a slight weakening of the attractive Casimir force. We acknowledge a known subtlety in the literature: because the Chern-Simons interaction is a total derivative, some analyses conclude that it should not contribute to the Casimir energy for standard boundary conditions, implying the leading correction is of higher order, $\order(S_z^4)$. For experimentally accessible plate separations ($a \sim \qty{1}{\micro\meter}$), the effect remains well below current detection thresholds ($|\Delta P/P_0| \lesssim 10^{-30}$) due to stringent bounds on macroscopic torsion from spin-torsion coupling experiments. Nevertheless, the calculation establishes a consistent, gauge-invariant bridge between quantum vacuum phenomena and non-Riemannian geometry. We discuss finite-temperature effects and geometric asymmetries as potential pathways for enhancing sensitivity, while placing the results in the broader context of dynamical torsion, condensed matter analogs, and quantum information protocols. Our results are consistent with the CPT-odd photon sector of the Standard-Model Extension and provide a geometric interpretation of Lorentz-violating coefficients in terms of spacetime torsion.

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Quantum Physics

On quantum mechanics self-consistency: EPR incompleteness claims require no extraneous concepts beyond the theory's plain formalism for refutation

D. F. Orsini, L. R. N. Oliveira and M. G. E. da Luz

From a phenomenological and experimental viewpoint, quantum mechanics is remarkably successful in explaining effects and processes in the microscopic world. Recently, however, a growing body of literature has revisited the theory's own formal foundations, specifically addressing issues of self-consistency and completeness. As a major historical example of these foundational challenges, the Einstein-Podolsky-Rosen (EPR) argument famously claimed that the theory is incomplete. While many valid criticisms and refutations of the EPR logic exist, they generally rely on a combination of technical results and conceptual objections to EPR's interpretive assumptions, thus transcending the plain quantum framework itself. Motivated by these trends of examining the theory's structural limits, here we revisit the EPR argument. Focusing on elements essential to the EPR reasoning, we first analyze general quantum correlations for EPR states: (i) the fact that their observables are always associated with non-commuting operators, and (ii) the nature of the correlated information obtained through measurement. From these two points alone, and relying strictly on the core rules of quantum mechanics, we demonstrate how to overturn the alleged EPR incompleteness without invoking any extraneous propositions. Consequently, we show that the standard formalism alone suffices to resolve such type of skepticism regarding the theory's physical reach. This offers, at least in a paradigmatic instance, a powerful indication of a structurally well-founded, self-consistent quantum theory.

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Computational Physics · Cross-listed from cs.LO

Exploiting Structure in the Boolean Weighted Constraint Satisfaction Problem: A Constraint Composite Graph-Based Approach

Hong Xu

What is "structure," and how can we exploit it in combinatorial optimization? Reasoning tasks such as system design, state estimation, and prediction can be cast as combinatorial optimization problems (COPs), traditionally attacked by dedicated algorithms that fail outside their narrow subclass, while communities working on equivalent problems reinvent each other's techniques. The weighted constraint satisfaction problem (WCSP) is a general framework that subsumes COPs from many communities and represents complex physical and non-physical systems, from spin glasses to social networks. Is such generality a curse? Our answer is to exploit "structure": a general-purpose WCSP algorithm should automatically imitate the specialized algorithm for whatever subclass its input belongs to. A WCSP has macro (graphical) structure, which variables interact, and micro (numerical) structure, how they interact. Separate schools of thought exploit one or the other, never both. The constraint composite graph (CCG), introduced in 2008, unifies them: it is an undirected graph over a WCSP instance's variables plus auxiliary ones, on which minimum weighted vertex cover (MWVC) solves the original instance. It is efficiently constructible, but largely unexploited. This dissertation answers three questions affirmatively. The CCG has theoretical advantages beyond identifying tractable classes (new properties proved here); it is practically useful (efficient implementation and experiments); and it extends promisingly to non-Boolean variables (new encodings). We use the CCG to (a) kernelize a WCSP instance, fixing optimal values of some variables by maxflow before search begins, (b) improve min-sum message passing, (c) exploit integer linear programming solvers, and (d) solve COPs on quantum annealers. Solving general COPs faster classically also yields better baselines for the debated quantum advantage.

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Earth and Planetary Astrophysics

What can Planetary Ice Shells Teach Us about Ocean Mixing and Life, and Why Salt Matters

Nicole Shibley

Past and present climates, both on Earth and in planetary systems, maintain ice covers with underlying oceans. This can range from sea ice in the Arctic Ocean to global ice shells on ice-covered moons in the Solar System to ice sheets in past episodes of Earth's history. When an ice shell overlies an ocean, it becomes challenging to infer what ocean processes could be going on below as in-situ ocean measurements are often lacking. This means that what we learn about ocean mixing must often be inferred from above-surface measurements. Here we synthesize the following ideas: (1) surface observations of past and present planetary ice shells give insight into subsurface ocean stratifications and mixing (and vice versa), (2) the stratification, mixing, and presence of ice in (1) is largely controlled by the ocean salinity, and (3) the interplay between (1) and (2) in past and present planetary systems may provide new insights into habitability and the origins of life.

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Materials Science

Sn-Doping in LPCVD-Grown (010) $\beta$-Ga$_2$O$_3$ Films

Saleh Ahmed Khan, Ahmed Ibreljic, Sourav Sarker et al. (+1 more)

In this work, Sn-doped (010) $\beta$-Ga$_2$O$_3$ homoepitaxial films were grown by low-pressure chemical vapor deposition (LPCVD), and the influence of Sn incorporation on their structural, morphological, and electrical properties was systematically investigated. Controlled room-temperature carrier concentrations ranging from $1.17 \times 10^{17}$ to $3.06 \times 10^{18}$ cm$^{-3}$ were achieved, with corresponding Hall mobilities decreasing from 113 to 63 cm$^2$ V$^{-1}$ s$^{-1}$. The films exhibited the monoclinic $\beta$-Ga$_2$O$_3$ phase, near-stoichiometric composition, and well-defined step-flow morphology, with a minimum rocking-curve FWHM of 68.4 arcsec and an RMS roughness of 2.63 nm. Film thicknesses ranging from 1.66 to 11.3 $\mu$m were obtained at growth rates of 6.4 to 16.6 $\mu$m h$^{-1}$, demonstrating the ability of LPCVD to produce thick epitaxial layers. The sample with a room-temperature carrier concentration of $1.17 \times 10^{17}$ cm$^{-3}$ exhibited room-temperature and low-temperature Hall mobilities of 113 cm$^2$ V$^{-1}$ s$^{-1}$ and 380 cm$^2$ V$^{-1}$ s$^{-1}$ at 84 K, respectively. Both represent the highest reported values for LPCVD-grown Sn-doped $\beta$-Ga$_2$O$_3$. Transport modeling of the same sample yielded a shallow donor activation energy of 32.7 meV, a deeper donor level at 95 meV, and a low compensating acceptor concentration of $2.0 \times 10^{16}$ cm$^{-3}$, indicating efficient donor activation and a low degree of compensation. These results demonstrate that LPCVD enables controlled Sn doping while maintaining excellent structural and electrical quality, providing a viable route for realizing thick $\beta$-Ga$_2$O$_3$ epitaxial drift layers.

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All authors Saleh Ahmed Khan, Ahmed Ibreljic, Sourav Sarker, Anhar Bhuiyan

High Energy Astrophysical Phenomena

Insights into the Pulsar Timing Array hypothesis space

El Mehdi Zahraoui, Patricio Maturana-Russel, Willem van Straten et al. (+2 more)

We present novel insights into the pulsar-noise model space in pulsar timing array (PTA) experiments. Through a comparative analysis of the same Parkes PTA second data release observations processed with the 2020 and 2023 pipelines, we show that data processing materially changes the distribution of posterior support across competing noise hypotheses and increases sensitivity to weak contributions such as the solar wind. A solar-wind component appears in the highest-posterior hypothesis for ten pulsars under the 2023 pipeline, against four under the 2020 pipeline, while the corresponding mean electron density estimates are consistent with PPTA DR3 results. Furthermore, hypothesis-space analysis exposes model competition and degeneracies that are hidden by single-model summaries. Approximately 75% of the pulsars retain substantial posterior support for alternative noise descriptions. Therefore, understanding the nature of the pulsar noise hypothesis space is crucial for robust inference and nanohertz gravitational-wave background searches.

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All authors El Mehdi Zahraoui, Patricio Maturana-Russel, Willem van Straten, Renate Meyer, Sergei Gulyaev

Physics and Society · Cross-listed from econ.GN

The friendship paradox: Causal evidence of its behavioral consequences

Gary Charness, Francesco Feri, Matthew O. Jackson et al. (+2 more)

We provide a first causal analysis of the behavioral consequences of the friendship paradox-the fact that people's friends in a network have more connections than average. We find that people's behavior is biased by their network position: they do not best respond to what they should infer the average behavior of the population to be (which determines their payoff), but instead best respond to the average behavior of their friends. In these games of complements, the friendship paradox generates a systematic upward distortion in actions and increases behavioral dispersion. These behavioral distortions persist despite learning opportunities: subjects fail to overcome the bias even when relocated within the network which should help them to understand how average population behavior can differ from local friend behavior.

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All authors Gary Charness, Francesco Feri, Matthew O. Jackson, Miguel A. Melendez-Jimenez, Matthias Sutter

Instrumentation and Methods for Astrophysics

Overview and status of BICEP Array's BA4-90/150 CMB polarimeter

M. A. Petroff, P. A. R. Ade, Z. Ahmed et al. (+83 more)

The inflation paradigm postulates a period of rapid expansion in the early Universe, which would generate gravitational waves. These tensor perturbations would produce a faint B-mode signature in the polarization of the cosmic microwave background (CMB), but this signal is orders of magnitude weaker than that from the CMB's other anisotropy and that from astrophysical foregrounds. Placing more-stringent upper limits on this signal or making a definitive detection thus requires exceptional control over instrument and measurement systematics, in addition to extremely-deep maps. The fourth BICEP Array receiver, BA4-90/150, aims to build and improve upon the heritage of the field-leading BICEP series of small-aperture CMB experiments with a dichroic instrument observing in 90 and 150 GHz bands, to advance the search for the inflationary B-mode signal. The instrument will utilize transition-edge-sensor bolometers, which will be read out using a new two-level time-division-multiplexed system and be fed via feedhorn-coupled orthomode transducers and refined cold refractive optics, with the goal of both improving systematics control and sensitivity over existing receivers. With a planned deployment to the South Pole in the 2026-27 austral summer, the instrument will occupy the fourth and final remaining slot in the BICEP Array mount, completing the phaseout of Keck Array receivers. An overview of the BA4-90/150 receiver will be presented, along with a discussion of its current status and future plans for the instrument.

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All authors M. A. Petroff, P. A. R. Ade, Z. Ahmed, M. Amiri, D. Barkats, R. Basu Thakur, C. A. Bischoff, D. Beck, J. J. Bock, V. Buza, B. Cantrall, J. R. Cheshire IV, J. Connors, J. Cornelison, M. Crumrine, A. J. Cukierman, E. Denison, L. Duband, M. A. Echter, M. Eiben, B. D. Elwood, S. Fatigoni, J. P. Filippini, A. Fortes, M. Gao, C. Giannakopoulos, N. Goeckner-Wald, D. C. Goldfinger, S. Gratton, J. A. Grayson, A. Greathouse, P. K. Grimes, M. Halpern, S. Henderson, T. D. Hoang, J. Hubmayr, H. Hui, K. D. Irwin, M. Izquierdo Poza, J. H. Kang, K. S. Karkare, S. Kefeli, J. M. Kovac, C. Kuo, K. Lasko, K. Lau, M. Lautzenhiser, T. Liu, S. C. Mackey, N. Maher, K. G. Megerian, L. Minutolo, L. Moncelsi, Y. Nakato, H. T. Nguyen, R. O'Brient, S. N. Paine, A. Patel, A. R. Polish, T. Prouve, C. Pryke, C. D. Reintsema, T. Romand, M. Salatino, A. Schillaci, B. Schmitt, B. Singari, A. Soliman, T. St. Germaine, A. Steiger, B. Steinbach, R. Sudiwala, K. L. Thompson, C. Tucker, A. D. Turner, C. Vergès, A. G. Vieregg, A. Wandui, A. C. Weber, J. Willmert, W. L. K. Wu, H. Yang, C. Yu, L. Zeng, C. Zhang, S. Zhang

Atomic Physics

Probing $P,T$-Symmetry Violation with Optically Trapped Asymmetric Top Molecules

Yuxi Yang, Arian Jadbabaie, Lukáš Félix Pašteka et al. (+3 more)

Searches for $P,T$-violating electromagnetic moments are among the most sensitive probes of physics beyond the Standard Model. Extending beyond current limits will benefit from molecules with fully controllable orientation at low electric fields, long coherence times, and laser coolability—all offered by asymmetric top molecules (ATMs). Exploiting the intrinsic rotational $K$-doubling in ATMs and the associated long-lived ($T_1 \gtrsim 10$ s) parity doublets afforded by $C_{2v}$ symmetry and nuclear-spin statistics, these species combine large electric polarizability with long coherence times in modest laboratory fields. We study alkaline-earth(-like) monoamides, $\mathcal{M}$–NH$_2$ ($\mathcal{M}$ = Ca, Sr, Ba, Yb, Ra), which possess favorable electronic structure for laser cooling. We perform ab initio calculations of fine and hyperfine constants, identifying the importance of relativistic effects in the spin-rotation tensor. An effective Hamiltonian then models the rotational and hyperfine structure of the vibronic ground state, quantifying electron electric dipole moment (EDM) sensitivities and identifying feasible measurement schemes. We compute the effect of external fields and identify engineered clock transitions that suppress sensitivity to external perturbations while retaining strong EDM sensitivity, and characterize the magic trapping conditions that null differential light shifts in an optical trap. Under these conditions we project a statistical electron-EDM sensitivity over an order of magnitude beyond current best experimental limits, with further gains available from increased molecule number and coherence time. Our results establish asymmetric top molecules as a tunable platform for sensitive symmetry-violation measurements with long coherence times.

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All authors Yuxi Yang, Arian Jadbabaie, Lukáš Félix Pašteka, I. Agustín Aucar, Rob G. E. Timmermans, Nicholas R. Hutzler

Quantum Physics

A Universal Entanglement Witness Generator

Aiden R. Rosebush, Alexander C. B. Greenwood, Andi Shahaj et al. (+1 more)

Entanglement witnesses are essential for certifying entanglement, yet constructing ones that are both noise-robust and economical in measurement settings remains challenging - particularly beyond qubits and for non-stabilizer ("magic") states. We present a machine-learning method that, given a target state and a user-specified number of measurement settings, generates an entanglement witness optimized for noise tolerance in the neighborhood of that state, requiring only local measurements. The approach is fully general, applying to multipartite qubit and qudit systems alike, including non-stabilizer states. For N qudits of dimension d, we train on the fully-separable eigenstates of each qudit's SU(d) generators to find a prototype witness, then tune the witness's bias term via gradient descent to maximize noise tolerance. Adversarial training further strengthens the witnesses, delivering greater noise tolerance with even fewer settings; critically, under this scheme the required training-set size becomes independent of system size. We package the entire pipeline as an automated script that, in every case we tested, produces witnesses surpassing all existing methods in noise tolerance and/or number of measurement settings. We demonstrate the method on Bell, GHZ, W, and hypergraph states, along with a range of qudit states, spanning 2-6 qubits, bipartite qudits up to d=10, and tripartite qutrits. Our witnesses achieve perfect accuracy across both physical experimental test states and large numerical sets of separable mixed states-including 30 million test states for a 3-qubit W-state witness and 10 million for a 4-qubit hypergraph-state witness-and we experimentally confirm the noise tolerance of Bell- and hypergraph state witnesses on both photonic and superconducting platforms, respectively.

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All authors Aiden R. Rosebush, Alexander C. B. Greenwood, Andi Shahaj, Li Qian

Mathematical Physics · Cross-listed from math.FA

A counterexample to the Kato conjecture for positive commutators

Rupert L. Frank and Paata Ivanisvili

We disprove the conjectural converse to Kato's positivity criterion for commutators of functions of the canonical position and momentum operators $Q$ and $P$ by showing that the operator \[ i\,[\,\arctan(P),\,\arctan(Q)\,] \] is nonnegative and nonzero.

Cosmology and Nongalactic Astrophysics

Inflationary Axion Isocurvature in the CMB across All Ultralight Masses

Rayne Liu, Wayne Hu and Daniel Grin

If the Peccei-Quinn symmetry of an ultralight axion is broken before the end of inflation, axion quantum fluctuations seed isocurvature perturbations, linking them to the tensor-to-scalar ratio $r$. We extend the effective time average (ETA) approach of the Boltzmann code ${\rm AxiECAMB}$ to accurately evolve these perturbations across the full axion mass range from dark energy ($m_a \lesssim H_0$) to dark matter ($m_a \gg 10^{-28}$ eV) types. We provide analytic fitting formulae for the axion abundance given the initial field value $\phi_{\rm ini}$, accurate at sub-percent level for $m_a \gg H_0$ and allowed dark matter fraction $f_{\rm dm}$. In the dark matter regime, the Planck bound on CDM isocurvature requires $r\ f_{\rm dm} < 0.08\,(m_a/10^{-27}\,{\rm eV})^{-1/2}$, which becomes stronger than the current BICEP tensor bound for $m_a f_{\rm dm}^2 \gtrsim 10^{-26.4}\,{\rm eV}$. For $10^{-32} \lesssim m_a/{\rm eV} \lesssim 10^{-28}$, Jeans suppression breaks the degeneracy with CDM isocurvature, leaving unique signatures, and in the dark energy regime ($m_a \lesssim H_0$), the isocurvature signal is even more highly suppressed, peaking only at the CMB quadrupole. We provide analytic scalings for both signatures. Given the tensor bound, any primary CMB detection in these two lightest regimes would indicate a non-inflationary origin of the isocurvature modes or a breakdown of the standard frozen-field misalignment scenario. A window of coexistence opens near $m_a \sim 10^{-25}$ eV and $f_{\rm dm} \gtrsim 0.1$ where both axion isocurvature and tensor modes could be discovered just below current bounds while simultaneously alleviating the $S_8$ tension.

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Solar and Stellar Astrophysics

The $\delta$ Scuti pulsator occurrence as a function of age, $T_{\rm eff}$, rotation, and metallicity

Ian Berry, Daniel Huber, Yaguang Li et al. (+3 more)

Many A- and F- type stars do not display $\delta$ Scuti pulsations, despite being located within the instability strip. We use photometry from the TESS Mission to discover and study $\delta$ Scuti pulsators in open clusters within 500 pc and with ages between ~20 and 900 Myr, which provide a unique opportunity to study $\delta$ Scuti pulsators in coeval populations with uniform chemical composition. We measure pulsator occurrence, which corrects the pulsator fraction for incompleteness, across all clusters. We find that clusters younger than 200 Myr tend to exhibit higher occurrence rates, with an average occurrence of 88$\pm$3%. The occurrence rates in clusters older than 200 Myr tend to resemble the pulsator fraction of field-star samples, with an average occurrence of 62$\pm$3%. In addition, we find that pulsators tend to rotate more rapidly in older clusters than their younger counterparts and that hotter pulsators may stop pulsating earlier than their cooler counterparts. These results show that pulsator occurrence decreases with age and that rapid rotation is critical in maintaining $\delta$ Scuti pulsations over time.

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All authors Ian Berry, Daniel Huber, Yaguang Li, Daniel Hey, Timothy R. Bedding, Simon J. Murphy

Cosmology and Nongalactic Astrophysics

The Impact of Splashback Galaxies on Galaxy Assembly Bias

Hernan Rincon, Idit Zehavi, Sergio Contreras et al. (+2 more)

The clustering of galaxies is affected by the assembly history of their underlying dark matter halos. This complex phenomenon, known as galaxy assembly bias, has been extensively studied, but the exact physical origin remains unclear. Splashback halos, typically low-mass halos that have traversed larger neighboring halos, have been suggested to be associated with halo assembly bias. Using a semi-analytic galaxy-formation model applied to the Millennium simulation, we explicitly explore the role that splasback galaxies play in galaxy assembly bias. We identify splashbacks as present-day central galaxies that were formerly satellites of a more massive host, and construct stellar-mass selected galaxy samples with the splashbacks either removed or reclassified as satellites of their former host halo. We find that splashbacks tend to reside in low-mass, highly concentrated halos and in dense environments, and that they have relatively high stellar-to-halo mass ratios. Splashbacks appear to be largely responsible for the low-mass tail of the occupancy variation for highly concentrated halos and for halos in dense environments. Finally, when computing the impact of assembly bias on galaxy clustering, we find that while removing the splashbacks significantly reduces the signal, reassigning them has little effect on its amplitude but shifts the transition scale. We repeat the analysis with the hydrodynamical simulation TNG300, confirming the robustness of our results. Our results provide insight into assembly bias and have potential implications for modeling the galaxy-halo connection.

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All authors Hernan Rincon, Idit Zehavi, Sergio Contreras, Yikun Wang, Xiaoju Xu

Biological Physics · Cross-listed from q-bio.MN

Permutation theory governs long-term dynamics of critical Boolean networks

Venkata Sai Narayana Bavisetty, Matthew Wheeler, Julian Vignes et al. (+4 more)

Boolean networks are widely used to model gene regulatory Attractors of Boolean networks model stable gene-expression patterns, yet deriving their properties from network structure remains an open problem. We solve this problem for critical $K=1$ networks by showing that their feedback loops induce a permutation whose order bounds the average attractor length both above and below by universal constant factors. This correspondence allows classical results from combinatorics and number theory to be applied directly to Boolean network dynamics. We find three distinct asymptotic scales for both average and maximum attractor lengths: typical networks scale as $\exp[(1/8+o(1))(\ln N)^2]$, the ensemble means grow as $\exp[N^{1/3+o(1)}]$, and extremal networks attain $\exp[(1+o(1))\sqrt{N\ln N}]$. Thus, ensemble averages are governed by rare network realizations and are unrepresentative of typical dynamics.

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All authors Venkata Sai Narayana Bavisetty, Matthew Wheeler, Julian Vignes, Matthew Stephen Jones Jr., Ruodan Liu, Sean Campbell, Claus Kadelka