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Within the framework of quantum mechanics over a quadratic extension of the non-Archimedean field of p-adic numbers, we provide a definition of a quantum state relying on a general algebraic approach and on a p-adic model of probability…

Mathematical Physics · Physics 2023-06-06 Paolo Aniello , Stefano Mancini , Vincenzo Parisi

In these two related parts we present a set of methods, analytical and numerical, which can illuminate the behaviour of quantum system, especially in the complex systems. The key points demonstrating advantages of this approach are: (i)…

Quantum Physics · Physics 2009-11-11 Antonina N. Fedorova , Michael G. Zeitlin

Quantum entanglement is a particularly useful characterization of topological orders which lack conventional order parameters. In this work, we study the entanglement in topologically ordered states between two arbitrary spatial regions,…

Strongly Correlated Electrons · Physics 2023-08-01 Chao Yin , Shang Liu

Classical surfaces in phase space correspond to quantum states in Hilbert space. Subsystems specify factor spaces of the Hilbert space. An entangled state corresponds semiclassically to a surface that cannot be decomposed into a product of…

Quantum Physics · Physics 2007-05-23 A. M. Ozorio de Almeida

An integral of the Wigner function of a wavefunction |psi >, over some region S in classical phase space is identified as a (quasi) probability measure (QPM) of S, and it can be expressed by the |psi > average of an operator referred to as…

Quantum Physics · Physics 2009-11-11 Demosthenes Ellinas , Ioannis Tsohantjis

Understanding coupled electron-phonon systems is one of the fundamental issues in strongly correlated systems. In this work, we aim to extend the notion of mixed-state phases to the realm of coupled electron/spinphonon systems.…

Strongly Correlated Electrons · Physics 2025-03-11 Brett Min , Yuxuan Zhang , Yuxuan Guo , Dvira Segal , Yuto Ashida

We give a new class of equivalent norms for modulation spaces by replacing the window of the short-time Fourier transform by a Hilbert-Schmidt operator. The main result is applied to Cohen's class of time-frequency distributions, Weyl…

Functional Analysis · Mathematics 2020-06-08 Eirik Skrettingland

Almost all novel observable phenomena in quantum optics are related to the quantum coherence. The coherence here is determined by the relative phase inside a state. Unfortunately, so far all the relevant experimental results in quantum…

Quantum Physics · Physics 2007-05-23 Wang Xiang-bin , Matsumoto Keiji , Tomita Akihisa

We present other examples illustrating the operator-theoretic approach to invariant integrals on quantum homogeneous spaces developed by Kuersten and the second author. The quantum spaces are chosen such that their coordinate algebras do…

Quantum Algebra · Mathematics 2009-04-07 Osvaldo Osuna Castro , Elmar Wagner

Let H(1), H(2) be complex Hilbert spaces, H be their Hilbert tensor product and let tr2 be the operator of taking the partial trace of trace class operators in H with respect to the space H(2). The operation tr2 maps states in H (i.e.…

Mathematical Physics · Physics 2015-06-26 J. Kupsch , O. G. Smolyanov , N. A. Sidorova

We introduce a Werner-like mixture [R. F. Werner, Phys. Rev. A {\bf 40}, 4277 (1989)] by considering two correlated but different degrees of freedom, one with discrete variables and the other with continuous variables. We evaluate the…

Quantum Physics · Physics 2009-11-07 Anna Felicetti , Stefano Mancini , Paolo Tombesi

Devoted to multi-task learning and structured output learning, operator-valued kernels provide a flexible tool to build vector-valued functions in the context of Reproducing Kernel Hilbert Spaces. To scale up these methods, we extend the…

Machine Learning · Computer Science 2018-05-25 Romain Brault , Florence d'Alché-Buc , Markus Heinonen

It is well known that the classification of pure multiparticle entangled states according to stochastic local operations leads to a natural classification of mixed states in terms of convex sets. We present a simple algorithmic procedure to…

Quantum Physics · Physics 2012-09-11 Hermann Kampermann , Otfried Gühne , Colin Wilmott , Dagmar Bruß

We study the range of time-frequency localization operators acting on modulation spaces and prove a lifting theorem. As an application we also characterize the range of Gabor multipliers, and, in the realm of complex analysis, we…

Functional Analysis · Mathematics 2014-07-17 Karlheinz Gröchenig , Joachim Toft

The convolution operator is the fundamental building block of modern convolutional neural networks (CNNs), owing to its simplicity, translational equivariance, and efficient implementation. However, its structure as a fixed, linear,…

Computer Vision and Pattern Recognition · Computer Science 2026-03-16 Simone Cammarasana

Recent years have witnessed a growing interest in using machine learning to predict and identify phase transitions in various systems. Here we adopt convolutional neural networks (CNNs) to study the phase transitions of Vicsek model,…

Biological Physics · Physics 2023-06-27 Tingting Xue , Xu Li , Xiaosong Chen , Li Chen , Zhangang Han

Entanglement is a fundamental feature of quantum mechanics, playing a crucial role in quantum information processing. However, classifying entangled states, particularly in the mixed-state regime, remains a challenging problem, especially…

We propose an alternating optimization algorithm to the nonconvex Koopman operator learning problem for nonlinear dynamic systems. We show that the proposed algorithm will converge to a critical point with rate $O(1/T)$ and $O(\frac{1}{\log…

Signal Processing · Electrical Eng. & Systems 2020-03-23 Zhiyuan Liu , Guohui Ding , Lijun Chen , Enoch Yeung

Transceivers used for telecommunications transmit and receive specific modulation patterns that are represented as sequences of complex numbers. Classifying modulation patterns is challenging because noise and channel impairments affect the…

Machine Learning · Computer Science 2020-10-30 Jakob Krzyston , Rajib Bhattacharjea , Andrew Stark

To study operator algebras with symmetries in a wide sense we introduce a notion of {\em relative convolution operators} induced by a Lie algebra. Relative convolutions recover many important classes of operators, which have been already…

funct-an · Mathematics 2008-02-03 Vladimir V. Kisil