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A popular approach to perform inference on a target parameter in the presence of nuisance parameters is to construct estimating equations that are orthogonal to the nuisance parameters, in the sense that their expected first derivative is…

Econometrics · Economics 2026-02-25 Stéphane Bonhomme , Koen Jochmans , Martin Weidner

The divergence of perturbative expansions for the vast majority of macroscopic systems, which follows from Dyson's collapse argument, prevents Feynman's diagrammatic technique from being directly used for controllable studies of strongly…

Statistical Mechanics · Physics 2011-03-14 Lode Pollet , Nikolay V. Prokof'ev , Boris V. Svistunov

In this paper we address the challenging problem of designing globally convergent estimators for the parameters of nonlinear systems containing a non-separable exponential nonlinearity. This class of terms appears in many practical…

Dynamical Systems · Mathematics 2022-11-17 Romeo Ortega , Alexey Bobtsov , Ramon Costa-Castello , Nikolay Nikolaev

We study a two-dimensional Fermi liquid with a Fermi surface containing the saddle points $(\pi,0)$ and $(0,\pi)$. Including Cooper and Peierls channel contributions leads to a one-loop renormalization group flow to strong coupling for…

Strongly Correlated Electrons · Physics 2009-10-31 Nobuo Furukawa , Manfred Salmhofer , T. M. Rice

This paper presents a simple periodic parameter-switching method which can find any stable limit cycle that can be numerically approximated in a generalized Duffing system. In this method, the initial value problem of the system is…

Chaotic Dynamics · Physics 2014-10-01 Marius-F. Danca , Nicolae Lung

The conventional model of the gauge vector field is invariant under the local conformal symmetry only in the four-dimensional space ($4d$). Conformal generalization to an arbitrary dimension $d$ is impossible even for the free theory,…

High Energy Physics - Theory · Physics 2021-12-03 Manuel Asorey , Lesław Rachwał , Ilya L. Shapiro , Wagno Cesar e Silva

A prey animal surveying its environment must decide whether there is a dangerous predator present or not. If there is, it may flee. Flight has an associated cost, so the animal should not flee if there is no danger. However, the prey animal…

Populations and Evolution · Quantitative Biology 2011-04-20 Joel Zylberberg , Michael R. DeWeese

We study a system of fermions interacting with a gauge field which can be used to describe either spin liquid or $\nu=1/2$ Quantum Hall state. We propose a generalized model with a dimensionless parameter $N$. We evaluate the properties of…

Condensed Matter · Physics 2007-05-23 L. B. Ioffe , D. Lidsky , B. L. Altshuler

It is well known that the presence of horseshoes leads to positive entropy. If our goal is to construct a continuous map with infinite entropy, we can consider an infinite sequence of horseshoes, ensuring an unbounded number of legs.…

Dynamical Systems · Mathematics 2024-02-23 Jeovanny de Jesus Muentes Acevedo

We study equilibrium density and spin density profiles for a model of cold one-dimensional spin 1/2 fermions interacting via inverse square interaction and exchange in an external harmonic trap. This model is the well-known spin-Calogero…

Quantum Gases · Physics 2011-02-01 M. Kulkarni , A. G. Abanov

We review the calculation of Fermi's golden rule for a system of $N$-body dipoles, magnetic or electric, weakly interacting with a blackbody radiation. By using the magnetic or electric field-field correlation function evaluated in the…

Quantum Physics · Physics 2016-09-26 Massimo Ostilli , Carlo Presilla

An inverse problem of elasticity of $n$ elastic inclusions embedded into an elastic half-plane is analyzed. The boundary of the half-plane is free of traction. The half-plane and the inclusions are subjected to antiplane shear, and the…

Complex Variables · Mathematics 2021-09-15 Y. A. Antipov

Motivated by a recent Diophantine transport problem about how to transport profitably a group of persons or objects, we survey classical facts about solving systems of linear Diophantine equations and inequalities in nonnegative integers.…

Number Theory · Mathematics 2020-03-31 Silvia Boumova , Vesselin Drensky , Boyan Kostadinov

An analysis of Wolfenstein parametrization for the Kobayashi-Maskawa matrix shows that it has a serious flaw: it depends on {\em three} independent parameters instead of {\em four} as it should be. Because this approximation is currently…

General Physics · Physics 2009-12-12 Petre Dita

Animals' internal states reflect variables like their position in space, orientation, decisions, and motor actions -- but how should these internal states be arranged? Internal states which frequently transition between one another should…

Neurons and Cognition · Quantitative Biology 2025-04-18 John J. Vastola

In this paper, optimal convergence for an adaptive finite element algorithm for elastoplasticity is considered. To this end, the proposed adaptive algorithm is established within the abstract framework of the axioms of adaptivity [Comput.…

Numerical Analysis · Mathematics 2024-04-09 Miriam Schönauer , Andreas Schröder

We consider the non-parametric Poisson regression problem where the integer valued response $Y$ is the realization of a Poisson random variable with parameter $\lambda(X)$. The aim is to estimate the functional parameter $\lambda$ from…

Statistics Theory · Mathematics 2018-05-14 Martin Kroll

We investigate a Lorentz-violating chiral model composed by two fermions, a complex scalar field and a gauge field. We show that by convenientely adjusting the parameters of the model, it is possible to generate an unambiguous…

High Energy Physics - Theory · Physics 2016-01-20 A. P. Baêta Scarpelli , M. Gomes , A. Yu. Petrov , A. J. da Silva

Motivated by the description of the graphene electronic structure in terms of the relativistic Dirac equation, a generalization to four dimensions yields a strictly local fermion action describing two species and possessing an exact chiral…

High Energy Physics - Lattice · Physics 2008-11-26 Michael Creutz

The elephant random walk is a history-dependent random walk. We study a class of interacting elephant random walks. Our model includes the exclusion process as a special case. By means of Monte Carlo simulations and mean-field arguments, we…

Statistical Mechanics · Physics 2018-11-21 Chikashi Arita , Eric Ragoucy