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Related papers: Reweighting Lefschetz Thimbles

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Deforming the domain of integration after complexification of the field variables is an intriguing idea to tackle the sign problem. In thimble regularization the domain of integration is deformed into an union of manifolds called Lefschetz…

High Energy Physics - Lattice · Physics 2021-11-30 Kevin Zambello , Francesco Di Renzo , Simran Singh

Although the complex Langevin method can solve the sign problem in simulations of theories with complex actions, the method will yield the wrong results if known validity conditions are not satisfied. We present a novel method to compute…

High Energy Physics - Lattice · Physics 2017-04-05 Jacques Bloch

The tempered Lefschetz thimble method (TLTM) is a parallel-tempering algorithm towards solving the numerical sign problem. It tames both the sign and ergodicity problems simultaneously by tempering the system with the flow time of…

High Energy Physics - Lattice · Physics 2020-01-07 Masafumi Fukuma , Nobuyuki Matsumoto , Naoya Umeda

We propose an efficient method to compute the so-called residual phase that appears when performing Monte Carlo calculations on a Lefschetz thimble. The method is stochastic and its cost scales linearly with the physical volume, linearly…

High Energy Physics - Lattice · Physics 2014-07-09 M. Cristoforetti , F. Di Renzo , G. Eruzzi , A. Mukherjee , C. Schmidt , L. Scorzato , C. Torrero

Thimble regularisation is a possible solution to the sign problem, which is evaded by formulating quantum field theories on manifolds where the imaginary part of the action stays constant (Lefschetz thimbles). A major obstacle is due to the…

High Energy Physics - Lattice · Physics 2021-03-03 Francesco Di Renzo , Simran Singh , Kevin Zambello

We propose a new algorithm based on the Metropolis sampling method to perform Monte Carlo integration for path integrals in the recently proposed formulation of quantum field theories on the Lefschetz thimble. The algorithm is based on a…

Computational Physics · Physics 2013-10-02 Abhishek Mukherjee , Marco Cristoforetti , Luigi Scorzato

Path reweighting is a principally exact method to estimate dynamic properties from biased simulations - provided that the path probability ratio matches the stochastic integrator used in the simulation. Previously reported path probability…

Chemical Physics · Physics 2021-03-02 Stefanie Kieninger , Bettina G. Keller

The reconstruction problem of voxels with individual weightings can be modeled a position- and angle- dependent function in the forward-projection. This changes the system matrix and prohibits to use standard filtered backprojection. In…

Computer Vision and Pattern Recognition · Computer Science 2020-10-28 Lina Felsner , Tobias Würfl , Christopher Syben , Philipp Roser , Alexander Preuhs , Andreas Maier , Christian Riess

The tempered Lefschetz thimble method is a parallel-tempering algorithm towards solving the numerical sign problem. It uses the flow time of the gradient flow as a tempering parameter and is expected to tame both the sign and multimodal…

Strongly Correlated Electrons · Physics 2019-12-25 Masafumi Fukuma , Nobuyuki Matsumoto , Naoya Umeda

A solution to the sign problem is the so-called "Lefschetz thimble approach" where the domain of integration for field variables in the path integral is deformed from the real axis to a sub-manifold in the complex space. For properly chosen…

High Energy Physics - Lattice · Physics 2016-06-01 Andrei Alexandru , Gokce Basar , Paulo F. Bedaque , Gregory W. Ridgway , Neill C. Warrington

The generalized thimble method to treat field theories with sign problems requires repeatedly solving the computationally-expensive holomorphic flow equations. We present a machine learning technique to bypass this problem. The central idea…

High Energy Physics - Lattice · Physics 2017-11-15 Andrei Alexandru , Paulo Bedaque , Henry Lamm , Scott Lawrence

We study the properties of the multiplicative structure on valuations on convex sets. We prove a new version of the hard Lefschetz theorem for even translation invariant continuous valuations, and discuss related problems of integral…

Metric Geometry · Mathematics 2007-05-23 Semyon Alesker

Reweighted l1-algorithms have attracted a lot of attention in the field of applied mathematics. A unified framework of such algorithms has been recently proposed by Zhao and Li. In this paper we construct a few new examples of reweighted…

Optimization and Control · Mathematics 2013-04-25 Mohammad Javad Abdi

The numerical sign problem is a major obstacle to the quantitative understanding of many important physical systems with first-principles calculations. Typical examples for such systems include finite-density QCD, strongly-correlated…

High Energy Physics - Lattice · Physics 2022-05-03 Masafumi Fukuma , Nobuyuki Matsumoto , Yusuke Namekawa

We analyze an algorithm for assigning weights prior to scalarization in discrete multi-objective problems arising from data analysis. The algorithm evolves weights (interpreted as the relevance of features) by a replicator-type dynamic on…

Optimization and Control · Mathematics 2026-05-08 Aris Daniilidis , Alberto Domínguez Corella , Philipp Wissgott

We present the first practical Monte Carlo calculations of the recently proposed Lefschetz thimble formulation of quantum field theories. Our results provide strong evidence that the numerical sign problem that afflicts Monte Carlo…

High Energy Physics - Lattice · Physics 2013-11-15 Marco Cristoforetti , Francesco Di Renzo , Abhishek Mukherjee , Luigi Scorzato

It is an old idea to replace averages of observables with respect to a complex weight by expectation values with respect to a genuine probability measure on complexified space. This is precisely what one would like to get from complex…

High Energy Physics - Lattice · Physics 2018-04-18 Błażej Ruba , Adam Wyrzykowski

Let $\mathfrak{g}$ be a semisimple Lie algebra over $\mathbb{C}$ having rank $l$ and let $V=L(\lambda)$ be an irreducible finite-dimensional $\mathfrak{g}$-module having highest weight $\lambda.$ Computations of weight multiplicities in…

Representation Theory · Mathematics 2016-04-06 Mikaël Cavallin

One strategy for reducing the sign problem in finite-density field theories is to deform the path integral contour from real to complex fields. If the deformed manifold is the appropriate combination of Lefschetz thimbles -- or somewhat…

High Energy Physics - Lattice · Physics 2018-09-12 Andrei Alexandru , Gokce Basar , Paulo F. Bedaque , Henry Lamm , Scott Lawrence

Matrix element reweighting is a powerful experimental technique widely employed to maximize the amount of information that can be extracted from a collider data set. We present a procedure that allows to automatically evaluate the weights…

High Energy Physics - Phenomenology · Physics 2011-02-02 P. Artoisenet , V. Lemaître , F. Maltoni , O. Mattelaer