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Carpet-type structures constitute an ideal laboratory to study and analyze the robustness of the interference process that underlies this phenomenon against the harmful effects of decoherence. Here, without losing any generality, for…

Quantum Physics · Physics 2021-06-14 E. Honrubia , A. S. Sanz

Standard methods used for computing the dynamics of a quantum many-body system are the mean-field (MF) approximations such as the time-dependent Hartree-Fock (TDHF) approach. Even though MF approaches are quite successful, they suffer some…

Nuclear Theory · Physics 2019-11-13 Ibrahim Ulgen , Bulent Yilmaz , Denis Lacroix

Density-corrected density functional theory (DC-DFT) is enjoying substantial success in improving semilocal DFT calculations in a wide variety of chemical problems. This paper provides the formal theoretical framework and assumptions for…

Chemical Physics · Physics 2019-08-19 Stefan Vuckovic , Suhwan Song , John Kozlowski , Eunji Sim , Kieron Burke

Kohn-Sham density functional theory (DFT) has long struggled with the accurate description of strongly correlated and open shell systems and improvements have been minor even in the newest hybrid functionals. In this Letter we treat the…

Chemical Physics · Physics 2021-04-01 Danny Gibney , Jan-Niklas Boyn , David A. Mazziotti

Denoising diffusion models have evolved into a state-of-the-art method for tasks in various fields, such as denoising and generation of images, text generation, or generation of synthetic data for training of other machine learning models.…

Statistics Theory · Mathematics 2026-05-11 Simon Bienewald , Lukas Trottner

In Ref. Ansari et al., dynamical quantum phase transitions (DQPTs) -- non-analyticities in the Loschmidt return rate at critical times -- are investigated in the presence of noise for a two-band model. The authors report that DQPTs persist…

Statistical Mechanics · Physics 2025-11-21 J. Sirker

Background: Sequential positivity is often a necessary assumption for drawing causal inferences, such as through marginal structural modeling. Unfortunately, verification of this assumption can be challenging because it usually relies on…

We examine the adiabatic dynamics of a quantum system coupled to a noisy classical control field. A stochastic phase shift is shown to arise in the off-diagonal elements of the system's density matrix which can cause decoherence. We derive…

Quantum Physics · Physics 2007-05-23 Frank Gaitan

Classical density functional theory (DFT) provides an exact variational framework for determining the equilibrium properties of inhomogeneous fluids. We report a generalization of DFT to treat the non-equilibrium dynamics of classical…

Soft Condensed Matter · Physics 2013-09-06 Matthias Schmidt , Joseph M. Brader

This article introduces a full mathematical and numerical framework for treating functional shapes (or fshapes) following the landmarks of shape spaces and shape analysis. Functional shapes can be described as signal functions supported on…

Computational Geometry · Computer Science 2014-04-25 Benjamin Charlier , Nicolas Charon , Alain Trouvé

Inhomogeneities in deposition may lead to formation of rough surfaces, whose height fluctuations can be probed directly by scanning microscopy, or indirectly by scattering. Analytical or numerical treatments of simple growth models suggest…

Condensed Matter · Physics 2009-10-28 Mehran Kardar

Transitions out of the ground space limit the performance of quantum adiabatic algorithms, while hardware imperfections impose stringent limitations on the circuit depth. We propose an adiabatic echo verification protocol which mitigates…

Quantum Physics · Physics 2024-09-06 Benjamin F. Schiffer , Dyon van Vreumingen , Jordi Tura , Stefano Polla

The structure and dynamics of a molecular system is governed by its potential energy surface (PES), representing the total energy as a function of the nuclear coordinates. Obtaining accurate potential energy surfaces is limited by the…

Chemical Physics · Physics 2023-09-29 Karl P. Horn , Luis Itza Vazquez-Salazar , Christiane P. Koch , Markus Meuwly

In many-body quantum systems, the quantum Fisher information an observer can obtain is susceptible to decoherence. Consequently, quantum enhanced metrology, such as Heisenberg scaling, cannot usually be achieved. We show, via two distinct…

Quantum Physics · Physics 2022-12-06 Le Hu , Shengshi Pang , Andrew Jordan

The derivation of the state of the art tensorial versions of Fundamental Measure Theory (a form of classical Density Functional Theory for hard spheres) are re-examined in the light of the recently introduced concept of global stability of…

Statistical Mechanics · Physics 2021-01-04 James F. Lutsko

Conventional frequency-domain full-waveform inversion (FWI) is typically implemented with an $L^2$ misfit function, which suffers from challenges such as cycle skipping and sensitivity to noise. While the Wasserstein metric has proven…

Optimization and Control · Mathematics 2025-10-10 Zhijun Zeng , Matej Neumann , Yunan Yang

The problem of detecting changes in covariance for a single pair of features has been studied in some detail, but may be limited in importance or general applicability. In contrast, testing equality of covariance matrices of a {\it set} of…

Methodology · Statistics 2017-12-12 Yi-Hui Zhou

In many physical systems it is expected that environmental decoherence will exhibit an asymmetry between dephasing and relaxation that may result in qubits experiencing discrete phase errors more frequently than discrete bit errors. In the…

Quantum Physics · Physics 2009-11-13 A. M. Stephens , Z. W. E. Evans , S. J. Devitt , L. C. L. Hollenberg

Nonadiabatic quantum interferences emerge whenever nuclear wavefunctions in different electronic states meet and interact in a nonadiabatic region. In this work, we analyze how nonadiabatic quantum interferences translate in the context of…

Chemical Physics · Physics 2016-08-03 Basile F. E. Curchod , Federica Agostini , E. K. U. Gross

In this paper we consider the problem of exact recovery of a fixed sparse vector with the measurement matrices sequentially arriving along with corresponding measurements. We propose an extension of the iterative hard thresholding (IHT)…

Information Theory · Computer Science 2021-03-02 Samrat Mukhopadhyay
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