Clay weekly context brief for the Physics category (ISO week 2026-W29).

Clay tracks publications from the Physics feed list. Below are recent items from this category, each with its source and a short description of what the publication covers when one is available in the source feed.

Recent publications:
1. Reformation of Supercritical Perpendicular Shock
   Source: physics.plasm-ph (Plasma Physics)
   Link: https://arxiv.org/abs/2607.09389
   Super-critical collisionless shocks are not static structures but evolve continuously as they reflect incoming ions back upstream.
2. The Statistical physics of unsaturated soil water: kinetic theory and non commutative pore water dynamics
   Source: physics.geo-ph (Geophysics)
   Link: https://arxiv.org/abs/2607.09416
   We develop a statistical-mechanical theory of water in unsaturated soil whose outcome is a continuum field equation for the pore-occupancy g(r,x,t), the fraction of pores of radius r that are water-filled at position x and time t.
3. Topological Signatures of Imperial Collapse and Fragmentation: Administrative Dissolution, Territorial Reorganization and Early-Warning Observables in the Han
   Source: physics.ed-ph (Physics Education)
   Link: https://arxiv.org/abs/2607.09010
   We extend the persistent homology formalism done in references~\cite{paper1,paper2} to the Han Dynasty ($206~\mathrm{BCE}$--$220~\mathrm{CE}$), testing whether the collapse threshold $\Hstar = 0.5241$ and the three-network decomposition methodology established for the Roman--Byzantine case generalize to a mechanistically distinct imperial system.
4. Toward quantum scaling advantage in approximate optimization
   Source: physics.comp-ph (Computational Physics)
   Link: https://arxiv.org/abs/2505.22514
   In a recent Letter [H.
5. Mean field homogenization schemes for composites with prolate and oblate spheroids: use of the orientation tensors and computation of the strain second-moments
   Source: physics.class-ph (Classical Physics)
   Link: https://arxiv.org/abs/2607.09213
   In this document we provide the homogenized stiffnesses from Mori-Tanaka scheme and Ponte-Casta{\~n}eda and Willis scheme applied to composites with spheroidal inclusions.
6. Cooperative control and geometric amplification in dissipative quantum systems
   Source: physics.atom-ph (Atomic Physics)
   Link: https://arxiv.org/abs/2606.30073
   In the control of dissipative quantum systems, the slow relaxation modes usually set the ultimate manipulation timescale.
7. Weak-Strong Steady-State Microbunching Accelerator Light Source
   Source: physics.acc-ph (Accelerator Physics)
   Link: https://arxiv.org/abs/2607.09243
   We propose a phase space manipulation involving one energy modulation sandwiched by two dispersion sections which converts a bunched particle beam or bunch train to ultra-high-harmonic density modulation, while the energy modulation in principle can be arbitrarily weak.
8. Quantum Approximate Optimization via Noise-Directed Adaptive Warm-Starting
   Source: quant-ph (Quantum Physics)
   Link: https://arxiv.org/abs/2607.09368
   Progress towards a quantum advantage using known heuristic methods for combinatorial optimization is impeded by hardware noise and limited qubit count.
9. Spectral Portfolio Theory: From SGD Weight Matrices to Wealth Dynamics
   Source: physics.soc-ph (Physics and Society)
   Link: https://arxiv.org/abs/2603.09006
   We develop spectral portfolio theory by establishing a direct identification: neural network weight matrices trained on stochastic processes are portfolio allocation matrices, and their spectral structure encodes factor decompositions and wealth concentration patterns.
10. DMRadio-Core: A new approach for GUT-scale axion searches
   Source: physics.ins-det (Instrumentation and Detectors)
   Link: https://arxiv.org/abs/2604.16602
   Searches for QCD axions with masses in the neV/$c^2$ mass range are strongly motivated by new physics at the GUT scale and by well-motivated pre-inflationary axion symmetry breaking scales.
11. Enhancing AI and Dynamical Subseasonal Forecasts with Probabilistic Bias Correction
   Source: physics.ao-ph (Atmospheric and Oceanic Physics)
   Link: https://arxiv.org/abs/2604.16238
   Decision-makers rely on weather forecasts to plant crops, manage wildfires, allocate water and energy, and prepare for weather extremes.
12. 3D Plasma plume characterization of an electrodeless thruster cluster in magnetic arch configuration
   Source: physics.plasm-ph (Plasma Physics)
   Link: https://arxiv.org/abs/2607.09509
   Clustering electrodeless plasma thrusters in pairs with opposing magnetic polarities offers an easy means to scale-up the propulsion system of future missions, and also, to mutually cancel their respective magnetic dipoles.
13. Inunda: A GPU-Native, Agent-enabled, Differentiable Solver for High-Resolution Flood Inundation Modeling
   Source: physics.geo-ph (Geophysics)
   Link: https://arxiv.org/abs/2607.09614
   Predicting where floodwater goes and how deep it gets, at high resolution and across large domains, remains computationally expensive with conventional hydraulic solvers, while purely data-driven surrogates are fast but lack physical guarantees and generalize poorly beyond their training events.
14. Defining a physics person: Tensions in the identity development of undergraduate women in physics
   Source: physics.ed-ph (Physics Education)
   Link: https://arxiv.org/abs/2606.16770
   This qualitative study explores how undergraduate women define what it means to be a physics person alongside how they describe their own physics identity.
15. Ab initio quantum embedding at finite temperature with density matrix embedding theory
   Source: physics.comp-ph (Computational Physics)
   Link: https://arxiv.org/abs/2601.01641
   We present a finite-temperature extension of density matrix embedding theory (FT-DMET) for realistic crystalline systems.
16. Unidirectional Transverse Scattering in Acoustic Dimers
   Source: physics.class-ph (Classical Physics)
   Link: https://arxiv.org/abs/2604.20690
   We study unidirectional transverse scattering in a two-dimensional acoustic dimer composed of two circular subwavelength scatterers.
17. Noncyclic geometric phase in three-level Ramsey interferometry for enhanced metrology
   Source: physics.atom-ph (Atomic Physics)
   Link: https://arxiv.org/abs/2606.18443
   In a standard two-level Ramsey interferometer, the accumulated signal phase is linearly mapped to the readout phase.
18. Optimizing the interaction geometry of inverse Compton scattering x-ray sources
   Source: physics.acc-ph (Accelerator Physics)
   Link: https://arxiv.org/abs/2512.20356
   Inverse Compton scattering (ICS) is a promising method for generating coherent and tunable x-rays in a compact setup.
19. Benchmarking Error Mitigation: Artefactual Improvements in Zero-Noise Extrapolation
   Source: quant-ph (Quantum Physics)
   Link: https://arxiv.org/abs/2607.09360
   Reliable benchmarking of Quantum Error Mitigation (QEM) requires distinguishing genuine improvements from artefacts of the post-processing arithmetic.

Sources in this brief: physics.acc-ph (Accelerator Physics); physics.ao-ph (Atmospheric and Oceanic Physics); physics.atom-ph (Atomic Physics); physics.class-ph (Classical Physics); physics.comp-ph (Computational Physics); physics.ed-ph (Physics Education); physics.geo-ph (Geophysics); physics.ins-det (Instrumentation and Detectors); physics.plasm-ph (Plasma Physics); physics.soc-ph (Physics and Society); quant-ph (Quantum Physics).
Selected 19 of 58 available items for this weekly brief.