25,180 research outputs found
On the Dirac field in the Palatini form of 1/R gravity
In recent papers (astro-ph/0306630, gr-qc/0312041) I have argued that the
observed cosmological acceleration can be accounted for by the inclusion of a
1/R term in the gravitational action in the Palatini formalism. Subsequently,
Flanagan (astro-ph/0308111, gr-qc/0403063) argued that this theory is
equivalent to a scalar-tensor theory which produces corrections to the standard
model that are ruled out experimentally.
In this article I examine the Dirac field coupled to 1/R gravity. The Dirac
action contains the connection which was taken to be the Christoffel symbol,
not an independent quantity, in the papers by Flanagan. Since the metric and
connection are taken to be independent in the Palatini approach it is natural
to allow the connection that appears in the Dirac action to be an independent
quantity. This is the approach that is taken in this paper. The resulting
theory is very different and much more complicated than the one discussed in
Flanagan's papers.Comment: 6 pages, LaTe
The retention of S35-labelled bovine serum albumin on normal and immunized rabbit liver tissue
The S35-label of S35-BSA was detected in the liver tissue of rabbits to the extent of 0.02 per cent (10 Āµg or sime 1014 molecules) of the injected material at 140 days after injection.
The rate of loss of antigen at the termination of the experiment was of such an order that significant amounts would be expected to persist for at least several years.
Data are reported which extend the retention data previously reported on S35-labelled hemocyanin. They indicate that amounts of the order of 0.05 per cent (25 Āµg.) of antigen material persist at 330 days after injection.
All of the radioactivity of material retained in the liver tissue 6 weeks after injection was immunologically related to the original S35-BSA antigen.
Preliminary studies are reported which indicate that the retained antigen is bound to ribonucleic acid.
A new method is described for the isolation of p-azophenylsulfonate bovine serum albumin from tissue extracts by means of a Dowex 2 adsorbent
A thread-tag based semantics for sequence diagrams
The sequence diagram is one of the most popular behaviour modelling languages which offers an intuitive and visual way of describing expected behaviour of object-oriented software. Much research work has investigated ways of providing a formal semantics for sequence diagrams. However, these proposed semantics may not properly interpret sequence diagrams when lifelines do not correspond to threads of controls. In this paper, we address this problem and propose a thread-tag based sequence diagram as a solution. A formal, partially ordered multiset based semantics for the thread-tag based sequence diagrams is proposed
A continuity argument for a semilinear Skyrme model
We investigate a semilinear modification for the wave map problem proposed by
Adkins and Nappi, and prove that in the equivariant case the solution remain
continuous at the first possible singularity
Capital Accumulation and Annuities in an Adverse Selection Economy
This paper suggests that adverse selection problems in competitive annuity markets can generate quantity constrained equilibria in which some agents whose length of lifetime is uncertain find it advantageous to accumulate capital privately. This occurs despite the higher rates of return on annuities. The welfare properties of these allocations are analyzed. It is shown that the level of capital accumulation is excessive in a Paretian sense. Policies which eliminate this inefficiency are discussed.
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