THE TYPE OF THE PHASE TRANSITION AND COUPLING VALUES IN λϕ⁴ MODEL

Abstract

The temperature induced phase transition is investigated in the one-component scalar field φ 4 model on the lattice. Using the GPU cluster a huge amount of Monte Carlo simulation data is collected for a wide interval of coupling values. This gives a possibility to determine the low bound on the coupling constant λ 0 when the transition happens and investigate its type. We found that for the values of λ close to this bound a weak-first-order phase transition takes place. It converts into a second order one with the increase of λ. A comparison with the results obtained in analytic and numeric calculations by other authors is given.

Critical line of the Φ^4 scalar field theory on a 4D cubic lattice in the local potential approximation

“…Recent Monte Carlo simulations suggest, according to the authors of reference [41], the existence of a weak first order transition, at low values of g , i.e. in the Gaussian limit.…”

QCDGPU: open-source package for Monte Carlo lattice simulations on OpenCL-compatible multi-GPU systems

“…(Pseudo)heat-bath algorithm is used for SU(N) model update. Improved Metropolis algorithm [7] is used for O(N) update.…”

“…Current HEP development leads to emerging the problems beyond this scope. The spontaneous vacuum magnetization at high temperature [5], phase transition behavior in external fields [6], dependence of the phase transition order in O(N) models on coupling constant value [7] and so on are some of such tasks. In 2008 we created the IDS package [8], which allows to research quantum effects in external chromomagnetic field.…”

“…In the first place methods and algorithms needed for actual research in the Quantum Chromoplasma Laboratory of Dnepropetrovsk National University is realized. Obtained physical results are published in particular in the works: [5], [7], etc.…”

On the type of the temperature phase transition in O(N) models within a perturbative analysis

“…Recently, in the O(1) model it was shown in lattice MC calculations that the PT type depends on the value of coupling constant λ . For λ ≤ 10 −3 a first order PT was detected and for larger λ it converts into a second order one [2]. This result is unexpected because it is usually assumed that the PT type is related with the analytic properties of some order parameter in the neighborhood of critical temperature T c .…”