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Related papers: Grassmann phase-space methods for fermions: uncove…

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Geometry and topology have generated impacts far beyond their pure mathematical primitive, providing a solid foundation for many applicable tools. Typically, real-world data are represented as vectors, forming a linear subspace for a given…

Quantum Physics · Physics 2024-05-01 Nhat A. Nghiem

Gaussian processes are popular and flexible models for spatial, temporal, and functional data, but they are computationally infeasible for large datasets. We discuss Gaussian-process approximations that use basis functions at multiple…

Methodology · Statistics 2020-12-22 Matthias Katzfuss , Wenlong Gong

We construct systematic expansions around four and two spatial dimensions for a Fermi gas near the unitarity limit. Near four spatial dimensions such a Fermi gas can be understood as a weakly interacting system of fermionic and bosonic…

Other Condensed Matter · Physics 2009-02-05 Yusuke Nishida , Dam Thanh Son

Geometrical aspects of quantum computing are reviewed elementarily for non-experts and/or graduate students who are interested in both Geometry and Quantum Computation. In the first half we show how to treat Grassmann manifolds which are…

Quantum Physics · Physics 2007-05-23 Kazuyuki Fujii

Gaussian Boson Sampling (GBS) is a near-term platform for photonic quantum computing. Recent efforts have led to the discovery of GBS algorithms with applications to graph-based problems, point processes, and molecular vibronic spectra in…

The Busemann function has recently found much interest in a variety of geometric machine learning problems, as it naturally defines projections onto geodesic rays of Riemannian manifolds and generalizes the notion of hyperplanes. As several…

Machine Learning · Computer Science 2026-03-13 Clément Bonet , Elsa Cazelles , Lucas Drumetz , Nicolas Courty

There are considered some corollaries of certain hypotheses on the observation process of microphenomena. We show that an enlargement of the phase space and of its motion group and an account for the diffusion motions of microsystems in the…

Quantum Physics · Physics 2007-05-23 E. M. Beniaminov

Gaussian quantum states of bosonic systems are an important class of states. In particular, they play a key role in quantum optics as all processes generated by Hamiltonians up to second order in the field operators (i.e. linear optics and…

Quantum Physics · Physics 2022-03-31 Jonatan Bohr Brask

The ground-state fidelity has been introduced recently as a tool to investigate quantum phase transitions. Here, we apply this concept in the context of a crossover problem. Specifically, we calculate the fidelity susceptibility for the BCS…

Statistical Mechanics · Physics 2009-07-03 A. Khan , P. Pieri

We describe quantum-field-theoretical (QFT) techniques for mapping quantum problems onto c-number stochastic problems. This approach yields results which are identical to phase-space techniques [C.W. Gardiner, {\em Quantum Noise} (1991)]…

Statistical Mechanics · Physics 2007-05-23 L. I. Plimak , M. Fleischhauer , M. K. Olsen , M. J. Collett

The Gaussian Wave-Packet phase-space representation is used to show that the expansion in powers of $\hbar$ of the quantum Liouville propagator leads, in the zeroth order term, to results close to those obtained in the statistical…

Atomic Physics · Physics 2009-10-30 G. W. Bund , S. S. Mizrahi , M. C. Tijero

In this work, we establish formally exact stochastic equations of motion (SEOM) theory to describe the dissipative dynamics of fermionic open systems. The construction of the SEOM is based on a stochastic decoupling of the dissipative…

Statistical Mechanics · Physics 2020-06-24 Lu Han , Arif Ullah , Yun-An Yan , Xiao Zheng , YiJing Yan , Vladimir Chernyak

We obtain a representation of pairing energies in phase space, for the Lipkin-Meshkov-Glick and general boson Bardeen-Cooper-Schrieffer pairing models. This is done by means of a probability distribution of the quantum state in phase space.…

Quantum Physics · Physics 2014-11-14 M. Calixto , O. Castaños , E. Romera

The Feynman path integral representation of quantum theory is used in a non--parametric Bayesian approach to determine quantum potentials from measurements on a canonical ensemble. This representation allows to study explicitly the…

Quantum Physics · Physics 2007-05-23 J. C. Lemm , J. Uhlig , A. Weiguny

The representation of quantum states via phase-space functions constitutes an intuitive technique to characterize light. However, the reconstruction of such distributions is challenging as it demands specific types of detectors and detailed…

Gibbs random fields play an important role in statistics, for example the autologistic model is commonly used to model the spatial distribution of binary variables defined on a lattice. However they are complicated to work with due to an…

Computation · Statistics 2012-07-25 Nial Friel

Several refinements are made in a theory which starts with a Planck-scale statistical picture and ends with supersymmetry and a coupling of fundamental fermions and bosons to SO(N) gauge fields. In particular, more satisfactory treatments…

High Energy Physics - Theory · Physics 2017-08-23 Roland E. Allen

It is apparent to anyone who thinks about it that, to a large degree, the basic concepts of Newtonian physics are quite intuitive, but quantum mechanics is not. My purpose in this talk is to introduce you to a new, much more intuitive way…

Quantum Physics · Physics 2009-02-12 Marvin Weinstein

Probabilities of vibronic transitions in molecules are referred to as Franck-Condon factors (FCFs). Although several approaches for calculating FCFs have been developed, such calculations are still challenging. Recently it was shown that…

Quantum Physics · Physics 2020-09-16 Kevin Valson Jacob , Eneet Kaur , Wojciech Roga , Masahiro Takeoka

Tensor network states, and in particular projected entangled pair states, play an important role in the description of strongly correlated quantum lattice systems. They do not only serve as variational states in numerical simulation…

Quantum Physics · Physics 2017-06-27 C. Wille , O. Buerschaper , J. Eisert