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Related papers: Saddle Points in the Auxiliary Field Method

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Stochastic saddle point (SSP) problems are, in general, less studied compared to stochastic minimization problems. However, SSP problems emerge from machine learning (adversarial training, e.g., GAN, AUC maximization), statistics (robust…

Optimization and Control · Mathematics 2023-12-14 Vitali Pirau

We study the $O(N)$ non-linear $\sigma$ model on three-dimensional manifolds of constant curvature by means of the large $N$ expansion at the critical point. We examine saddle point equations imposing anti-periodic boundary condition in…

High Energy Physics - Theory · Physics 2007-05-23 Kazuto Oshima

A variation to the usual formulation of Grassmann representation path integrals is presented. Time-indexed anticommuting partners are introduced for each Grassmann coherent state variable and a general method for handling the effect of…

Quantum Physics · Physics 2007-05-23 S. Shresta

We present a method to compute the two-point functions for an $O(N)$ scalar field model in de Sitter spacetime, avoiding the well known infrared problems for massless fields. The method is based on an exact treatment of the Euclidean zero…

High Energy Physics - Theory · Physics 2016-11-01 Diana López Nacir , Francisco D. Mazzitelli , Leonardo G. Trombetta

We compute the Gaussian-fluctuation corrections to the saddle-point Schwinger-boson results using collective coordinate methods. Concrete application to investigate the frustrated J1-J2 antiferromagnet on the square lattice shows that,…

Statistical Mechanics · Physics 2009-10-28 A. E. Trumper , L. O. Manuel , C. J. Gazza , H. A. Ceccatto

This paper is the completion of an earlier work arXiv:1207.4867 which involves the derivation of oblique corrections in the MSSM at one loop. In terms of the two-component spinor formalism, which is new in compared with those used in the…

High Energy Physics - Phenomenology · Physics 2012-12-27 Yao Yu , Sibo Zheng

Given a (2+1)D fermionic topological order and a symmetry fractionalization class for a global symmetry group $G$, we show how to construct a (3+1)D topologically invariant path integral for a fermionic $G$ symmetry-protected topological…

Strongly Correlated Electrons · Physics 2024-08-23 Sri Tata , Ryohei Kobayashi , Daniel Bulmash , Maissam Barkeshli

This technical note describes the application of saddle-point integration to the asymptotic Fourier analysis of the well-known $C_\infty$ "bump" function $\exp[-(1-x^2)^{-1}]$, deriving both the asymptotic decay rate $k^{-3/4} \exp(-\sqrt…

Complex Variables · Mathematics 2015-08-19 Steven G. Johnson

In the following article we provide an exposition of exact computational methods to perform parameter inference from partially observed network models. In particular, we consider the duplication attachment (DA) model which has a likelihood…

Computation · Statistics 2013-06-20 Junshan Wang , Ajay Jasra , Maria De Iorio

In recent articles [Mishima et al., Phys. Rev. A, 66, 033401(2002); Chao, Phys. Rev. A, 72, 053414 (2005)] it was proposed to use the residue theorem for the exact calculation of the transition amplitude describing strong-field ionization…

Atomic Physics · Physics 2013-05-29 Yulian V. Vanne , Alejandro Saenz

Recently, a method was proposed and tested to find saddle points of the action in simulations of non-abelian lattice gauge theory. The idea, called `extremization', is to minimize $\int(\dl S/\dl A_\mu)^2$. The method was implemented in an…

High Energy Physics - Lattice · Physics 2009-10-22 A. J. van der Sijs

Generalized additive index models (GAIMs) offer a flexible semiparametric framework for capturing complex data relationships, balancing the interpretability of parametric models with the flexibility of nonparametric approaches. However,…

Methodology · Statistics 2026-05-29 Ziyu Peng , Linglingzhi Zhu , Yao Xie

Recently, in (M. Masoudi, D.K. Salkuyeh, An extension of positive-definite and skew-Hermitian splitting method for preconditioning of generalized saddle point problems, Computers \& Mathematics with Application,…

Numerical Analysis · Mathematics 2021-09-13 Mohsen Masoudi , Davod Khojasteh Salkuyeh

The Fast Multipole Method (FMM) provides a highly efficient computational tool for solving constant coefficient partial differential equations (e.g. the Poisson equation) on infinite domains. The solution to such an equation is given as the…

Numerical Analysis · Mathematics 2012-01-04 A. Gillman , P. G. Martinsson

The goal of policy-based reinforcement learning (RL) is to search the maximal point of its objective. However, due to the inherent non-concavity of its objective, convergence to a first-order stationary point (FOSP) can not guarantee the…

Machine Learning · Computer Science 2020-12-04 Long Yang , Qian Zheng , Gang Pan

We present a versatile nonlinear model predictive control (NMPC) formulation for quadrupedal locomotion. Our formulation jointly optimizes a base trajectory and a set of footholds over a finite time horizon based on simplified dynamics…

Robotics · Computer Science 2022-07-22 Dongho Kang , Flavio De Vincenti , Stelian Coros

Current statistics literature on statistical inference of random fields typically assumes that the fields are stationary or focuses on models of non-stationary Gaussian fields with parametric/semiparametric covariance families, which may…

Statistics Theory · Mathematics 2024-09-04 Yunyi Zhang , Zhou Zhou

A lattice fermion model is formulated in Fock space using the Jordan-Wigner representation for the fermion creation and annihilation operators. The resulting path integral is a sum over configurations of lattice site occupation numbers…

High Energy Physics - Lattice · Physics 2009-10-22 Uwe-Jens Wiese

We simulate SU(2) gauge theory with six massless fundamental Dirac fermions. By using the Schr\"odinger Functional method we measure the running of the coupling and the fermion mass over a wide range of length scales. We observe very slow…

High Energy Physics - Phenomenology · Physics 2015-03-17 Francis Bursa , Luigi Del Debbio , Liam Keegan , Claudio Pica , Thomas Pickup

We study the saddlepoint approximation (SPA) for sums of $n$ i.i.d. random vectors $X_i\in\mathbb R^d$ in growing dimensions. SPA provides highly accurate approximations to probability densities and distribution functions via the moment…

Probability · Mathematics 2025-10-27 Alexander Katsevich