A bstract Using the Schwinger-Keldysh-formalism, reformulated in [1] as an effective field theory Euclidean anti-de Sitter, we evaluate one-loop cosmological four-point function of a conformally coupled interacting scalar de Sitter. Recasting Witten correlator flat space Feynman integrals, functions Sitter terms single-valued multiple polylogarithms. From it derive anomalous dimensions and OPE ...

We review applicability of QCD factorization theorem to multiple scattering in deeply inelastic lepton-nucleus scattering. We show why A1/3-type nuclear enhancement can be calculated consistently in perturbative QCD. We derive the transverse momentum broadening of the leading pions in deeply inelastic lepton-nucleus collisions. We argue that the measurement of such transverse momentum broadenin...

The slow dynamics of a system as it approaches a phase transition, associated with the slowing down in the decay of a correlation function, can be caused by a sharp increase in the probability of a particle’s returning to its original state following a transition, rather than to a slowing down in the transition rates as is usually assumed. The results of our calculations show that this is the c...

The choice of the mathematical form of spatial correlation functions for optical fields is restricted by the constraint of nonnegative definiteness. We discuss a sufficient condition for ensuring the satisfaction of such a constraint.

A cluster expansion is proposed, that applies to both continuous and discrete systems. The assumption for its convergence involves an extension of the neat Kotecký–Preiss criterion. Expressions and estimates for correlation functions are also presented. The results are applied to systems of interacting classical and quantum particles, and to a lattice polymer model. 2000 Math. Subj. Class. 82B0...

involving additional fields Φ̂I(z1)Φ̂I(z2) · · ·. Note that in eq. (3) the fields are in the interaction rather than Heisenberg picture, so they evolve with time as free fields according to the free Hamiltonian Ĥ0. Likewise, |0〉 is the free theory’s vacuum, i.e. the ground state of the free Hamiltonian Ĥ0 rather than the full Hamiltonian Ĥ. To work out the relation between (1) and (3), we start b...