Tootfinder

Nonreciprocal superradiant quantum phase transition induced by magnon Kerr effect
Guo-Qiang Zhang, Si-Yan Lin, Wei Feng, Yi-Hao Kang, Wei Xiong
https://arxiv.org/abs/2509.25985 …

Nonreciprocal superradiant quantum phase transition induced by magnon Kerr effect
Recently, proposals for realizing a nonreciprocal superradiant quantum phase transition (SQPT) have been put forward, based on either nonreciprocal interactions between two spin ensembles or the Sagnac-Fizeau shift in a spinning cavity. However, experimental implementation of such a nonreciprocal SQPT remains challenging. This motivates the search for new mechanisms capable of producing a nonreciprocal SQPT. Here, we propose an alternative approach to realize a nonreciprocal SQPT, induced by th…

Realizing Nonreciprocal Linear Dichroism and Emission from Simple Media
Thomas J. Ugras, Daniel J. Gracias, Oriol Arteaga, Richard D. Robinson
https://arxiv.org/abs/2507.23051 h…

Realizing Nonreciprocal Linear Dichroism and Emission from Simple Media
Reciprocity, the principle that a system response is identical in the forward path compared to the backward path, is a fundamental concept across physics, from electrical circuits and optics to acoustics and heat conduction. Nonreciprocity arises when this symmetry is broken, enabling directional-dependent behavior. In photonics, nonreciprocity allows control over the propagation of electromagnetic waves, essential for isolators and circulators. But achieving optical nonreciprocity typically re…

Nonreciprocal Coupling Induced by Nonlocal Loss Engineering
Yekai Shen, Shuhang Chen
https://arxiv.org/abs/2509.23754 https://arxiv.org/pdf/2509.23754

Nonreciprocal Coupling Induced by Nonlocal Loss Engineering
Nonreciprocal coupling between photonic modes enables a range of advanced functionalities, though the available approaches for its practical implementation remain limited. Here, we introduce a novel strategy for achieving nonreciprocal coupling via nonlocal, nonlinear loss. We prove that robust, broadband, and continuously tunable nonreciprocal coupling can be realized by engineering the loss rate as a function of the state of a nonlocal mode, as validated through effective Hamiltonian modeling…

Numerical approximations to invariant measures of hybrid stochastic differential equations with superlinear coefficients via the backward Euler-Maruyama method
Wei Liu, Jie Xu
https://arxiv.org/abs/2509.25799

Numerical approximations to invariant measures of hybrid stochastic differential equations with superlinear coefficients via the backward Euler-Maruyama method
For stochastic stochastic differential equations with Markovian switching, whose drift and diffusion coefficients are allowed to contain superlinear terms, the backward Euler-Maruyama (BEM) method is proposed to approximate the invariant measure. The existence and uniqueness of the invariant measure of the numerical solution generated by the BEM method is proved. Then the convergence of the numerical invariant measure to its underlying counterpart is shown. The results obtained in this work rel…

USA verkaufen Patriot-Luftabwehr an Dänemark
Die USA sind zur Lieferung mehrerer Patriot-Flugabwehrsysteme und anderer Waffen an den NATO-Partner Dänemark bereit, der die Ukraine im Abwehrkampf gegen Russland unterstützen will. Das Außenministerium in Washington genehmigte den Deal, dessen Umfang mit 8,5 Milliarden US-Dollar (7,3 Mrd Euro) beziffert wurde. Dänemark und andere NATO-Mitglieder wollen die Ukraine im Krieg gegen …
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Ukraine-Liveblog: ++ Russland spricht von Offensive an gesamter Front ++
Russland führt eigenen Angaben zufolge ununterbrochene Offensiven entlang der gesamt Frontlänge in der Ukraine durch. Kanzler Merz geht davon aus, dass der Krieg erst aufhört, wenn Russland ihn wirtschaftlich nicht mehr führen kann.

Parameter Estimation for GW200208\_22 with Targeted Eccentric Numerical-relativity Simulations
Patricia McMillin (RIT), Katelyn J. Wagner (RIT), Giuseppe Ficarra (UNICAL), Carlos O. Lousto (RIT), Richard O'Shaughnessy (RIT)
https://arxiv.org/abs/2507.22862

Parameter Estimation for GW200208\_22 with Targeted Eccentric Numerical-relativity Simulations
We have analyzed LVK gravitational wave events that show some evidence of eccentricity from TEOBResumS modeling parameter estimations and have confronted them independently with full numerical generated waveforms from our bank of nearly two thousand simulations of binary black holes. We have used RIFT for Bayesian parameter estimation and found that GW200208\_{22} KDE estimates favor eccentricities $e_{20} = 0.217_{-0.184}^{+0.076}$ upon entering the LVK band at $\sim20$Hz within a 90\% confide…

SymBoltz.jl: a symbolic-numeric, approximation-free and differentiable linear Einstein-Boltzmann solver
Herman Sletmoen
https://arxiv.org/abs/2509.24740 https://

SymBoltz.jl: a symbolic-numeric, approximation-free and differentiable linear Einstein-Boltzmann solver
SymBoltz is a new Julia package that solves the linear Einstein-Boltzmann equations. It features a symbolic-numeric interface for specifying equations, is free of approximation switching schemes and is compatible with automatic differentiation. Cosmological models are built from replaceable physical components in a way that scales well in model space. The modeler should simply write down their equations, and SymBoltz solves them and eliminates much of the friction in the process. SymBoltz enabl…

Wave propagation in an elastic lattice with non-reciprocal stiffness and engineered damping
Harshit Kumar Sandhu, Saurav Dutta, Rajesh Chaunsali
https://arxiv.org/abs/2507.23761

Wave propagation in an elastic lattice with non-reciprocal stiffness and engineered damping
Nonreciprocal wave propagation allows for directional energy transport. In this work, we systematically investigate wave dynamics in an elastic lattice that combines nonreciprocal stiffness with viscous damping. After establishing how conventional damping counteracts the system's gain, we introduce a non-dissipative form of nonreciprocal damping in the form of gyroscopic damping. We find that the coexistence of nonreciprocal stiffness and nonreciprocal damping results in a decoupled control mec…

Performance and Numerical Aspects of Decompositional Factorizations with FP64 Floating-Point Emulation in INT8
Piotr Luszczek, Vijay Gadepally, LaToya Anderson, William Arcand, David Bestor, William Bergeron, Alex Bonn, Daniel J. Burrill, Chansup Byun, Michael Houle, Matthew Hubbell, Hayden Jananthan, Michael Jones, Peter Michaleas, Guillermo Morales, Julia Mullen, Andrew Prout, Albert Reuther, Antonio Rosa, Charles Yee, Jeremy Kepner

Performance and Numerical Aspects of Decompositional Factorizations with FP64 Floating-Point Emulation in INT8
Mixing precisions for performance has been an ongoing trend as the modern hardware accelerators started including new, and mostly lower-precision, data formats. The advantage of using them is a great potential of performance gain and energy savings. The disadvantage are the numerical issues not present in the standard-mandated floating-point formats. Split integer emulation of FP64 takes this to an extreme with the computation performed only by fixed-point tensor core units. We present the new …

Structure-preserving numerical calculation of wave equation for a vector field
Takuya Tsuchiya
https://arxiv.org/abs/2509.26504 https://arxiv.org/pdf/2509.…

Structure-preserving numerical calculation of wave equation for a vector field
For the Proca equation, which is a wave equation for a vector field, we derive the canonical formulation including constraints from the Stueckelberg action and propose discrete equations with a structure-preserving scheme for conserving the constraints at the discrete level. Numerical simulations are performed using these discrete equations and other discrete equations with a standard scheme. We show the results obtained using the structure-preserving scheme and provide more accurate and stable…