Fermion bag approach to lattice field theories
Repository Usage Stats
We propose a new approach to the fermion sign problem in systems where there is a coupling U such that when it is infinite the fermions are paired into bosons, and there is no fermion permutation sign to worry about. We argue that as U becomes finite, fermions are liberated but are naturally confined to regions which we refer to as fermion bags. The fermion sign problem is then confined to these bags and may be solved using the determinantal trick. In the parameter regime where the fermion bags are small and their typical size does not grow with the system size, construction of Monte Carlo methods that are far more efficient than conventional algorithms should be possible. In the region where the fermion bags grow with system size, the fermion bag approach continues to provide an alternative approach to the problem but may lose its main advantage in terms of efficiency. The fermion bag approach also provides new insights and solutions to sign problems. A natural solution to the "silver blaze problem" also emerges. Using the three-dimensional massless lattice Thirring model as an example, we introduce the fermion bag approach and demonstrate some of these features. We compute the critical exponents at the quantum phase transition and find ν=0.87(2) and η=0.62(2). © 2010 The American Physical Society.
Published Version (Please cite this version)10.1103/PhysRevD.82.025007
Publication InfoChandrasekharan, S (2010). Fermion bag approach to lattice field theories. Physical Review D - Particles, Fields, Gravitation and Cosmology, 82(2). pp. 25007. 10.1103/PhysRevD.82.025007. Retrieved from https://hdl.handle.net/10161/4276.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
More InfoShow full item record
Professor of Physics
Prof. Chandrasekharan is interested in understanding quantum field theories non-perturbatively from first principles calculations. His research focuses on lattice formulations of these theories with emphasis on strongly correlated fermionic systems of interest in condensed matter, particle and nuclear physics. He develops novel Monte-Carlo algorithms to study these problems. He is particularly excited about solutions to the notoriously difficult <a href="http://en.wikipedia.org/wiki/Numerical_si