Temperature control by laminar flows

We have demonstrated that given the inlet temperature, the procedure of using the heat transfer coefficient or the cooling region lengths to control the surface temperature is well-posed and the iterative procedure converges rapidly. An analysis on a slightly simpler problem using a Neumann condition with a primary cooling region also showed that the problem is indeed well-posed

Flows in a low permeable and compressible medium

Fluid transport equation in porous media (Fluid compressibility) Two problems on flows in low permeability reservoirs were posed. One of the problems is on radial axi-symmetric flows with a threshold pressure gradient and the other is on radial flows in a compressible medium. The main objective of the exercise is to obtain exact or approximate solutions. We summarize the discussion on one of the two problems, flows in a slightly compressible medium

A magnetically driven origin for the low luminosity GRB 170817A associated with GW170817

The gamma-ray burst GRB 170817A associated with GW170817 is subluminous and subenergetic compared with other typical short GRBs. It may be due to a relativistic jet viewed off-axis, or a structured jet, or cocoon emission. Giant flares from magnetars may possibly be ruled out. However, the luminosity and energetics of GRB 170817A is coincident with that of magnetar giant flares. After the coalescence of the binary neutron star, a hypermassive neutron star may be formed. The hypermassive neutron star may have magnetar-strength magnetic field. During the collapse of the hypermassive neutron star, the magnetic field energy will also be released. This giant-flare-like event may explain the the luminosity and energetics of GRB 170817A. Bursts with similar luminosity and energetics are expected in future neutron star-neutron star or neutron star-black hole mergers.Comment: 6 pages, 1 figure, accepted in Research in Astronomy and Astrophysic

T invariance of Higgs interactions in the standard model

In the standard model, the Cabibbo-Kobayashi-Maskawa matrix, which incorporates the time-reversal violation shown by the charged current weak interactions, originates from the Higgs-quark interactions. The Yukawa interactions of quarks with the physical Higgs particle can contain further complex phase factors, but nevertheless conserve T, as shown by constructing the fermion T transformation and the invariant euclidean fermion measure.Comment: LaTeX, 4 pages; presented at PASCOS'0

New sum rule identities and duality relation for the Potts nn-point correlation function

It is shown that certain sum rule identities exist which relate correlation functions for $n$ Potts spins on the boundary of a planar lattice for $n\geq 4$. Explicit expressions of the identities are obtained for $n=4,5$. It is also shown that the identities provide the missing link needed for a complete determination of the duality relation for the $n$-point correlation function. The $n=4$ duality relation is obtained explicitly. More generally we deduce the number of correlation identities for any $n$ as well as an inversion relation and a conjecture on the general form of the duality relation.Comment: 11 pages in RevTeX, 4 PS figures, submitted to PR