57,959 research outputs found
Non-local 2D Generalized Yang-Mills theories on arbitrary surfaces with boundary
The non-local generalized two dimensional Yang Mills theories on an arbitrary
orientable and non-orientable surfaces with boundaries is studied. We obtain
the effective action of these theories for the case which the gauge group is
near the identity, . Furthermore, by obtaining the effective action
at the large-N limit, it is shown that the phase structure of these theories is
the same as that obtain for these theories on orientable and non-orientable
surface without boundaries. It is seen that the model of these
theories on an arbitrary orientable and non-orientable surfaces with boundaries
have third order phase transition only on and surfaces, with
modified area for orientable and
for non-orientable surfaces respectivly.Comment: 10 pages, no figures, late
A perturbative analysis of tachyon condensation
Tachyon condensation in the open bosonic string is analyzed using a
perturbative expansion of the tachyon potential around the unstable D25-brane
vacuum. Using the leading terms in the tachyon potential, Pad\'e approximants
can apparently give the energy of the stable vacuum to arbitrarily good
accuracy. Level-truncation approximations up to level 10 for the coefficients
in the tachyon potential are extrapolated to higher levels and used to find
approximants for the full potential. At level 14 and above, the resulting
approximants give an energy less than -1 in units of the D25-brane tension, in
agreement with recent level-truncation results by Gaiotto and Rastelli. The
extrapolated energy continues to decrease below -1 until reaching a minimum
near level 26, after which the energy turns around and begins to approach -1
from below. Within the accuracy of this method, these results are completely
consistent with an energy which approaches -1 as the level of truncation is
taken to be arbitrarily large.Comment: 8 pages, 3 eps figures, Latex; v2: typo correcte
The use of linear programming in least-cost feed compounding
Intensive types of livestock production such as
poultry and pigs promise to become of increasing
importance in New Zealand agriculture. In such enterprises,
feed costs constitute a very high proportion
of total variable costs. Any method of computing low
cost feeds is obviously of great importance.
Linear programming is one such method which has
been widely used overseas. In this bulletin Mr Taylor
applies this method to the problem of formulating
least-cost commercial feed compounds for broiler
chickens
Some comments about Schwarzschield black holes in Matrix theory
In the present paper we calculate the statistical partition function for any
number of extended objects in Matrix theory in the one loop approximation. As
an application, we calculate the statistical properties of K clusters of D0
branes and then the statistical properties of K membranes which are wound on a
torus.Comment: 15 page
A method for the reduction of aerodynamic drag of road vehicles
A method is proposed for the reduction of the aerodynamic drag of bluff bodies, particularly for application to road transport vehicles. This technique consists of installation of panels on the forward surface of the vehicle facing the airstream. With the help of road tests, it was demonstrated that the attachment of proposed panels can reduce aerodynamic drag of road vehicles and result in significant fuel cost savings and conservation of energy resources
Matrix embeddings on flat and the geometry of membranes
We show that given three hermitian matrices, what one could call a fuzzy
representation of a membrane, there is a well defined procedure to define a set
of oriented Riemann surfaces embedded in using an index function defined
for points in that is constructed from the three matrices and the point.
The set of surfaces is covariant under rotations, dilatations and translation
operations on , it is additive on direct sums and the orientation of the
surfaces is reversed by complex conjugation of the matrices. The index we build
is closely related to the Hanany-Witten effect. We also show that the surfaces
carry information of a line bundle with connection on them.
We discuss applications of these ideas to the study of holographic matrix
models and black hole dynamics.Comment: 41 pages, 3 figures, uses revtex4-1. v2: references added, corrected
an error in attribution of idea
Working Group 5: Measurements technology and active experiments
Technology issues identified by working groups 5 are listed. (1) New instruments are needed to upgrade the ability to measure plasma properties in space. (2) Facilities should be developed for conducting a broad range of plasma experiments in space. (3) The ability to predict plasma weather within magnetospheres should be improved and a capability to modify plasma weather developed. (4) Methods of control of plasma spacecraft and spacecraft plasma interference should be upgraded. (5) The space station laboratory facilities should be designed with attention to problems of flexibility to allow for future growth. These issues are discussed
Homotopy Lie Superalgebra in Yang-Mills Theory
The Yang-Mills equations are formulated in the form of generalized
Maurer-Cartan equations, such that the corresponding algebraic operations are
shown to satisfy the defining relations of homotopy Lie superalgebra.Comment: LaTeX2e, 10 page
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