166 research outputs found
Gauge Theory of Relativistic Membranes
In this paper we show that a relativistic membrane admits an equivalent
representation in terms of the Kalb-Ramond gauge field
encountered in string theory.
By `` equivalence '' we mean the following: if is a solution of the
classical equations of motion derived from the Dirac-Nambu-Goto action, then it
is always possible to find a differential form of {\it rank three}, satisfying
Maxwell-type equations. The converse proposition is also true. In the first
part of the paper, we show that a relativistic membrane, regarded as a
mechanical system, admits a Hamilton-Jacobi formulation in which the H-J
function describing a family of classical membrane histories is given by
. In the second part of the
paper, we introduce a {\it new} lagrangian of the Kalb-Ramond type which
provides a {\it first order} formulation for both open and closed membranes.
Finally, for completeness, we show that such a correspondence can be
established in the very general case of a p-brane coupled to gravity in a
spacetime of arbitrary dimensionality.Comment: 35 pages, PHYZZX, UTS-DFT-92-
Conformally Invariant Brane-universe and the Cosmological Constant
A relativistic 3-brane can be given a conformally invariant, gauge-type,
formulation provided the embedding space is six-dimensional. The implementation
of conformal invariance requires the use of a modified measure, independent of
the metric in the action. A brane-world scenario without the need of a
cosmological constant in 6D can be constructed. Thus, no ``old'' cosmological
constant problem appears at this level.Comment: 2 pages; Revtex; contribution to the Proceedings of the 10th Marcel
Grossman Meetin
Membrane Pregeometry and the Vanishing of the Cosmological Constant
We suggest a model of induced gravity in which the fundamental object is a
relativistic {\it membrane} minimally coupled to a background metric and to an
external three index gauge potential. We compute the low energy limit of the
two-loop effective action as a power expansion in the surface tension. A
generalized bootstrap hypothesis is made in order to identify the physical
metric and gauge field with the lowest order terms in the expansion of the
vacuum average of the composite operators conjugate to the background fields.
We find that the large distance behaviour of these classical fields is
described by the Einstein action with a cosmological term plus a Maxwell type
action for the gauge potential. The Maxwell term enables us to apply the
Hawking-Baum argument to show that the physical cosmological constant is
``~probably~'' zero.Comment: 14 pages, no figures, phyzzx macr
Membrane Vacuum as a Type II Superconductor
We study a functional field theory of membranes coupled to a rank--three
tensor gauge potential. We show that gauge field radiative corrections lead to
membrane condensation which turns the gauge field into a {\it massive spin--0
field}. This is the Coleman--Weinberg mechanism for {\it membranes}. An analogy
is also drawn with a type--II superconductor. The ground state of the system
consists of a two--phase medium in which the superconducting background
condensate is ``pierced'' by four dimensional domains, or ``bags'', of non
superconducting vacuum. Bags are bounded by membranes whose physical thickness
is of the order of the inverse mass acquired by the gauge field.Comment: 14 pages, no figures, LaTeX; to be Published on In.J.Mod.Phys.B
Umezawa Memorial Issu
Particle Propagator in Elementary Quantum Mechanics: a New Path Integral Derivation
This paper suggests a new way to compute the path integral for simple quantum
mechanical systems. The new algorithm originated from previous research in
string theory. However, its essential simplicity is best illustrated in the
case of a free non relativistic particle, discussed here, and can be
appreciated by most students taking an introductory course in Quantum
Mechanics. Indeed, the emphasis is on the role played by the {\it entire family
of classical trajectories} in terms of which the path integral is computed
exactly using a functional representation of the Dirac delta-distribution. We
argue that the new algorithm leads to a deeper insight into the connection
between classical and quantum systems, especially those encountered in high
energy physics.Comment: LaTex uses iopams package, 15pages, no figures, in print on Euro.J.of
Phy
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