Finite volume QCD at fixed topological charge
Abstract
In finite volume the partition function of QCD with a given θ is a sum of different topological sectors with a weight primarily determined by the topological susceptibility. If a physical observable is evaluated only in a fixed topological sector, the result deviates from the true expectation value by an amount proportional to the inverse space-time volume 1/V. Using the saddle point expansion, we derive formulas to express the correction due to the fixed topological charge in terms of a 1/V expansion. Applying this formula, we propose a class of methods to determine the topological susceptibility in QCD from various correlation functions calculated in a fixed topological sector.
- Publication:
-
Physical Review D
- Pub Date:
- September 2007
- DOI:
- 10.1103/PhysRevD.76.054508
- arXiv:
- arXiv:0707.0396
- Bibcode:
- 2007PhRvD..76e4508A
- Keywords:
-
- 12.38.Gc;
- 11.15.Ha;
- Lattice QCD calculations;
- Lattice gauge theory;
- High Energy Physics - Lattice;
- High Energy Physics - Theory
- E-Print:
- 22pages, references added