Experimental evidence for the existence of strictly higher-order phase transitions (of order three or above in the Ehrenfest sense) is tenuous at best. However, there is no known physical reason why such transitions should not exist in nature. Here, higher-order transitions characterized by both discontinuities and divergences are analysed through the medium of partition function zeros. Propert...

A recently developed technique to determine the order and strength of phase transitions by extracting the density of partition function zeroes (a continuous function) from finite-size systems (a discrete data set) is generalized to systems for which (i) some or all of the zeroes occur in degenerate sets and/or (ii) they are not confined to a singular line in the complex plane. The technique is ...

A one-dimensional branching-coalescing model is considered on a chain of length L with reflecting boundaries. We study the phase transitions of this model in a canonical ensemble by using the Yang-Lee description of the non-equilibrium phase transitions. Numerical study of the canonical partition function zeros reveals two second-order phase transitions in the system. Both transition points are...

When solutions of poly(ethylene glycol) and dextran are mixed above certain concentrations, they form two immiscible aqueous phases: a poly(ethylene glycol)-rich top phase and a dextranrich bottom phase. These solutions can be buffered and made isotonic. Cells and organelles added to such systems will partition between the two phases and the horizontal interface between them. Depending on the c...

We obtain the hadronic mass spectrum in the ‘bag of bags’ statistical bootstrap model (BBSBM), implementing the colorless state condition, aside of baryon and strangeness conservation, using group projection method. We study the partition function, investigate the properties of dense hadronic matter, and determine the conditions under which the system undergoes a phase transition to a deconfine...

We report new results on complex-temperature properties of Ising models. These include studies of the s = 1/2 model on triangular, honeycomb, kagomé, 3·12, and 4·8 lattices. We elucidate the complex–T phase diagrams of the higher-spin 2D Ising models, using calculations of partition function zeros. Finally, we investigate the 2D Ising model in an external magnetic field, mapping the complex–T p...

The properties of the QCD partition function at finite chemical potential are studied within the instanton liquid model. It is shown that the density dependence of the quarkinduced instanton-antiinstanton (I-A) interaction leads to the formation of topologically neutral I-A pairs (’molecules’), resulting in a first order chiral phase transition at a critical chemical potential μq ' 310 MeV. At ...

We study the one-dimensional asymmetric simple exclusion process (ASEP) with open boundary conditions. Particles are injected and ejected at both boundaries. It is clarified that the steady state of the model is intimately related to the AskeyWilson polynomials. The partition function and the n-point functions are obtained in the integral form with four boundary parameters. The thermodynamic cu...