Renormalization of the 2PI Hartree-Fock approximation on de Sitter background in the broken phase

The infrared effects for light minimally coupled scalar fields with quartic self-interaction in de Sitter space is investigated using the 2PI effective action formalism. This formalism partially resums infinite series of loop diagrams, and enables us to circumvent the IR divergence problem for a massless minimally coupled scalar field in de Sitter space. It is anticipated that nonperturbative infrared effects generate a curvature-induced mass and self-regulate the IR divergence. However, due to its nonperturbative nature, the renormalization prescription is a nontrivial task. To calculate physical quantities, an appropriate renormalization prescription is required. In this paper, we will show that the MS-like scheme is possible at the Hartree-Fock truncation of the 2PI effective action, and infinite series of divergent terms are needed as counterterms. The phase structure and the quantum backreaction to Einstein's field equation are calculated.Comment: 25 pages, 2 figures, title changed, section 1 and 6 revised, typos corrected, results not change

How Flow Changes Polymer Depletion in a Slit

A theoretical model is developed for predicting dynamic polymer depletion effects under the influence of fluid flow. The results are established by combining the two-fluid model and the self-consistent field theory. We consider a uniform fluid flow across a slit containing a solution with polymer chains. The two parallel and infinitely long walls are permeable to solvent only and the polymers do not adsorb to these walls. For a weak flow and a narrow slit in Theta-solvent conditions, an analytic expression is derived to describe the steady state polymer concentration profiles. In both Theta- and good-solvents, we compute the time evolution of the concentration profiles for various flow rates characterized by the Peclet number. The model reveals the interplay of depletion, solvent condition, slit width, and relative strength of the fluid flow.Comment: 12 pages, 12 figure

Nonperturbative infrared effects for light scalar fields in de Sitter space

We study the phi^4 scalar field theory in de Sitter space using the 2PI effective action formalism. This formalism enables us to investigate the nonperturbative quantum effects. We use the mean field and gap equations and calculate the physical mass and effective potential. We find that nonperturbative infrared effects on de Sitter space produce a curvature-induced mass and work to restore the broken Z_2 symmetry.Comment: 14 pages, 3 figures, section 2 revised, discussion in section 4 changed, results not change

PREPARATION OF 5H,7H-DIBENZ[c,e]OXEPIN-5-ONE DERIVATIVE THROUGH RECONSTRUCTION OF THE LACTONE RING

The systematic investigation of the efficient transformation of 6H-dibenzo[b,d]pyran-6-one into 5H,7H-dibenz[c,e]oxepin-5-one is described

Comparison of Fe-Mg interdiffusion coefficients in olivine

We have compared Fe-Mg interdiffusion coefficients in olivine reported in several literatures by analyzing experimentally produced diffusion profiles. The chemical zoning profiles of olivine measured with an electron microprobe were compared with those calculated by numerically solving the diffusion equation by using different diffusion coefficients. For our experimental results, the Fe-Mg interdiffusion coefficient in olivine reported by D. J. Misener (Carnegie Inst. Washington Publ., 634,117,1974) with oxygen fugacity dependence gives the best fit to the observed profile. The Fe-concentration dependence of the Fe-Mg interdiffusion coefficient in olivine is important when the Fe content varies widely