977 research outputs found
Monopole Condensates in Seiberg-Witten Theory
A product of two Riemann surfaces of genuses p_1 and p_2 solves the
Seiberg-Witten monopole equations for a constant Weyl spinor that represents a
monopole condensate. Self-dual electromagnetic fields require p_1=p_2=p and
provide a solution of the euclidean Einstein-Maxwell-Dirac equations with p-1
magnetic vortices in one surface and the same number of electric vortices in
the other. The monopole condensate plays the role of cosmological constant. The
virtual dimension of the moduli space is zero, showing that for given p_1 and
p_2, the solutions are unique.Comment: 10 page
Geometry of 2d spacetime and quantization of particle dynamics
We analyze classical and quantum dynamics of a particle in 2d spacetimes with
constant curvature which are locally isometric but globally different. We show
that global symmetries of spacetime specify the symmetries of physical
phase-space and the corresponding quantum theory. To quantize the systems we
parametrize the physical phase-space by canonical coordinates. Canonical
quantization leads to unitary irreducible representations of group.Comment: 12 pages, LaTeX2e, submitted for publicatio
Singular solutions to the Seiberg-Witten and Freund equations on flat space from an iterative method
Although it is well known that the Seiberg-Witten equations do not admit
nontrivial solutions in flat space, singular solutions to them have been
previously exhibited -- either in or in the dimensionally reduced spaces
and -- which have physical interest. In this work, we employ an
extension of the Hopf fibration to obtain an iterative procedure to generate
particular singular solutions to the Seiberg-Witten and Freund equations on
flat space. Examples of solutions obtained by such method are presented and
briefly discussed.Comment: 7 pages, minor changes. To appear in J. Math. Phy
Liouville Vortex And Kink Solutions Of The Seiberg--Witten Equations
The Seiberg--Witten equations, when dimensionally reduced to \bf R^{2}\mit,
naturally yield the Liouville equation, whose solutions are parametrized by an
arbitrary analytic function . The magnetic flux is the integral of
a singular Kaehler form involving ; for an appropriate choice of ,
coaxial or separated vortex configurations with are
obtained when the integral is regularized. The regularized connection in the
\bf R^{1}\mit case coincides with the kink solution of theory.Comment: 14 pages, Late
Binary Black Hole Mergers from Planet-like Migrations
If supermassive black holes (BHs) are generically present in galaxy centers,
and if galaxies are built up through hierarchical merging, BH binaries are at
least temporary features of most galactic bulges. Observations suggest,
however, that binary BHs are rare, pointing towards a binary lifetime far
shorter than the Hubble time. We show that, regardless of the detailed
mechanism, all stellar-dynamical processes are insufficient to reduce
significantly the orbital separation once orbital velocities in the binary
exceed the virial velocity of the system. We propose that a massive gas disk
surrounding a BH binary can effect its merger rapidly, in a scenario analogous
to the orbital decay of super-jovian planets due to a proto-planetary disk. As
in the case of planets, gas accretion onto the secondary (here a supermassive
BH) is integrally connected with its inward migration. Such accretion would
give rise to quasar activity. BH binary mergers could therefore be responsible
for many or most quasars.Comment: 8 pages, submitted to ApJ Letter
Fractional Dirac Bracket and Quantization for Constrained Systems
So far, it is not well known how to deal with dissipative systems. There are
many paths of investigation in the literature and none of them present a
systematic and general procedure to tackle the problem. On the other hand, it
is well known that the fractional formalism is a powerful alternative when
treating dissipative problems. In this paper we propose a detailed way of
attacking the issue using fractional calculus to construct an extension of the
Dirac brackets in order to carry out the quantization of nonconservative
theories through the standard canonical way. We believe that using the extended
Dirac bracket definition it will be possible to analyze more deeply gauge
theories starting with second-class systems.Comment: Revtex 4.1. 9 pages, two-column. Final version to appear in Physical
Review
Is my ODE a Painleve equation in disguise?
Painleve equations belong to the class y'' + a_1 {y'}^3 + 3 a_2 {y'}^2 + 3
a_3 y' + a_4 = 0, where a_i=a_i(x,y). This class of equations is invariant
under the general point transformation x=Phi(X,Y), y=Psi(X,Y) and it is
therefore very difficult to find out whether two equations in this class are
related. We describe R. Liouville's theory of invariants that can be used to
construct invariant characteristic expressions (syzygies), and in particular
present such a characterization for Painleve equations I-IV.Comment: 8 pages. Based on talks presented at NEEDS 2000, Gokova, Turkey, 29
June - 7 July, 2000, and at the AMS-HKMS joint meeting 13-16 December, 2000.
Submitted to J. Nonlin. Math. Phy
Representations of an integer by some quaternary and octonary quadratic forms
In this paper we consider certain quaternary quadratic forms and octonary
quadratic forms and by using the theory of modular forms, we find formulae for
the number of representations of a positive integer by these quadratic forms.Comment: 20 pages, 4 tables. arXiv admin note: text overlap with
arXiv:1607.0380
The Binet-Legendre Metric in Finsler Geometry
For every Finsler metric we associate a Riemannian metric (called
the Binet-Legendre metric). The transformation is -stable
and has good smoothness properties, in contrast to previous constructions. The
Riemannian metric also behaves nicely under conformal or bilipshitz
deformation of the Finsler metric . These properties makes it a powerful
tool in Finsler geometry and we illustrate that by solving a number of named
Finslerian geometric problems. We also generalize and give new and shorter
proofs of a number of known results. In particular we answer a question of M.
Matsumoto about local conformal mapping between two Minkowski spaces, we
describe all possible conformal self maps and all self similarities on a
Finsler manifold. We also classify all compact conformally flat Finsler
manifolds, solve a conjecture of S. Deng and Z. Hou on the Berwaldian character
of locally symmetric Finsler spaces, and extend the classic result of H.C. Wang
about the maximal dimension of the isometry groups of Finsler manifolds to
manifolds of all dimensions.
Most proofs in this paper go along the following scheme: using the
correspondence we reduce the Finslerian problem to a similar
problem for the Binet-Legendre metric, which is easier and is already solved in
most cases we consider. The solution of the Riemannian problem provides us with
the additional information that helps to solve the initial Finslerian problem.
Our methods apply even in the absence of the strong convexity assumption
usually assumed in Finsler geometry. The smoothness hypothesis can also be
replaced by that of partial smoothness, a notion we introduce in the paper. Our
results apply therefore to a vast class of Finsler metrics not usually
considered in the Finsler literature.Comment: 33 pages, 5 figures. This version is slightly reduced fron versions 1
and 2. The paper has been published in Geometry & Topolog
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