7,402 research outputs found
New non-linear equations and modular form expansion for double-elliptic Seiberg-Witten prepotential
Integrable N-particle systems have an important property that the associated
Seiberg-Witten prepotentials satisfy the WDVV equations. However, this does not
apply to the most interesting class of elliptic and double-elliptic systems.
Studying the commutativity conjecture for theta-functions on the families of
associated spectral curves, we derive some other non-linear equations for the
perturbative Seiberg-Witten prepotential, which turn out to have exactly the
double-elliptic system as their generic solution. In contrast with the WDVV
equations, the new equations acquire non-perturbative corrections which are
straightforwardly deducible from the commutativity conditions. We obtain such
corrections in the first non-trivial case of N=3 and describe the structure of
non-perturbative solutions as expansions in powers of the flat moduli with
coefficients that are (quasi)modular forms of the elliptic parameter.Comment: 25 page
Unitary matrix integrals in the framework of Generalized Kontsevich Model. I. Brezin-Gross-Witten Model
We advocate a new approach to the study of unitary matrix models in external
fields which emphasizes their relationship to Generalized Kontsevich Models
(GKM) with non-polynomial potentials. For example, we show that the partition
function of the Brezin-Gross-Witten Model (BGWM), which is defined as an
integral over unitary matrices, , can also be considered as a GKM with potential . Moreover, it can be interpreted as the generating functional for
correlators in the Penner model. The strong and weak coupling phases of the
BGWM are identified with the "character" (weak coupling) and "Kontsevich"
(strong coupling) phases of the GKM, respectively. This sort of GKM deserves
classification as one (i.e. or ) when in the Kontsevich
phase. This approach allows us to further identify the
Harish-Chandra-Itzykson-Zuber (IZ) integral with a peculiar GKM, which arises
in the study of theory and, further, with a conventional 2-matrix model
which is rewritten in Miwa coordinates. Inspired by the considered unitary
matrix models, some further extensions of the GKM treatment which are inspired
by the unitary matrix models which we have considered are also developed. In
particular, as a by-product, a new simple method of fixing the Ward identities
for matrix models in an external field is presented.Comment: FIAN/TD-16/93, ITEP-M6/93, UBC/S-93/93 (39 pages
Octonic Electrodynamics
In this paper we present eight-component values "octons", generating
associative noncommutative algebra. It is shown that the electromagnetic field
in a vacuum can be described by a generalized octonic equation, which leads
both to the wave equations for potentials and fields and to the system of
Maxwell's equations. The octonic algebra allows one to perform compact combined
calculations simultaneously with scalars, vectors, pseudoscalars and
pseudovectors. Examples of such calculations are demonstrated by deriving the
relations for energy, momentum and Lorentz invariants of the electromagnetic
field. The generalized octonic equation for electromagnetic field in a matter
is formulated.Comment: 12 pages, 1 figur
Is Strong Gravitational Radiation predicted by TeV-Gravity?
In TeV-gravity models the gravitational coupling to particles with energies
E\sim m_{Pl} \sim 10 TeV is not suppressed by powers of ultra-small ratio
E/M_{Pl} with M_{Pl} \sim 10^{19} GeV. Therefore one could imagine strong
synchrotron radiation of gravitons by the accelerating particles to become the
most pronounced manifestation of TeV-gravity at LHC. However, this turns out to
be not true: considerable damping continues to exist, only the place of
E/M_{Pl} it taken by a power of a ratio \theta\omega/E, where the typical
frequency \omega of emitted radiation, while increased by a number of
\gamma-factors, can not reach E/\vartheta unless particles are accelerated by
nearly critical fields. Moreover, for currently available magnetic fields B
\sim 10 Tesla, multi-dimensionality does not enhance gravitational radiation at
all even if TeV-gravity is correct.Comment: 7 pages, LaTe
Superpolynomials for toric knots from evolution induced by cut-and-join operators
The colored HOMFLY polynomials, which describe Wilson loop averages in
Chern-Simons theory, possess an especially simple representation for torus
knots, which begins from quantum R-matrix and ends up with a trivially-looking
split W representation familiar from character calculus applications to matrix
models and Hurwitz theory. Substitution of MacDonald polynomials for characters
in these formulas provides a very simple description of "superpolynomials",
much simpler than the recently studied alternative which deforms relation to
the WZNW theory and explicitly involves the Littlewood-Richardson coefficients.
A lot of explicit expressions are presented for different representations
(Young diagrams), many of them new. In particular, we provide the
superpolynomial P_[1]^[m,km\pm 1] for arbitrary m and k. The procedure is not
restricted to the fundamental (all antisymmetric) representations and the torus
knots, still in these cases some subtleties persist.Comment: 23 pages + Tables (51 pages
Stabilization of higher-order vortices and multi-hump solitons in media with synthetic nonlocal nonlinearities
We address the evolution of higher-order excited states, such as vortex and
multi-hump solitons, in nonlocal media with synthetic, competing focusing and
defocusing nonlinearities with different nonlocal transverse scales. We reveal
that introduction of suitable competing effects makes possible the
stabilization of vortex solitons with topological charge m>2, as well as
one-dimensional multi-hump solitons with number of humps p>4, all of which are
highly unstable in natural nonlocal materials with focusing nonlinearities.Comment: 14 pages, 5 figures, to appear in Physical Review
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