Theta-vacuum systems via real action simulations

Abstract

Inspired by the results of the Ising model within an imaginary external magnetic field, we introduce a transformation in quantum systems with a theta-vacuum term that amounts to a rescaling of z=cos(theta/2). Making use of this transformation we are able to determine the order parameter as a function of theta. The approach is successfully tested in models with both broken and unbroken CP symmetry at theta=pi.

14 pages, 6 figures; To appear in Phys. Lett. B

References in corpus (8)

• A new approach to the complex-action problem and its application to a nonperturbative study of superstring theory
• Meron-Cluster Simulation of the $\theta$-Vacuum in the 2-d $O(3)$-Model
• The factorization method for systems with a complex action -a test in Random Matrix Theory for finite density QCD-
• New proposal for numerical simulations of theta-vacuum like systems
• Parity and CT realization in QCD
• CP(N-1) Models with Theta Term and Fixed Point Action
• Monte Carlo Studies of Two-Dimensional Systems with a $\theta$ Term
• Two dimensional CP^2 Model with θ-term and Topological Charge Distributions

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