41,483 research outputs found
Classical Integrable N=1 and Super Sinh-Gordon Models with Jump Defects
The structure of integrable field theories in the presence of jump defects is
discussed in terms of boundary functions under the Lagrangian formalism.
Explicit examples of bosonic and fermionic theories are considered. In
particular, the boundary functions for the N=1 and N=2 super sinh-Gordon models
are constructed and shown to generate the Backlund transformations for its
soliton solutions. As a new and interesting example, a solution with an
incoming boson and an outgoing fermion for the N=1 case is presented. The
resulting integrable models are shown to be invariant under supersymmetric
transformation.Comment: talk presented at the V International Symposium on Quantum Theory and
Symmetries, Valladolid, Spain, July 22-28,200
Photonics-enabled sub-Nyquist radio frequency sensing based on temporal channelization and compressive sensing
A novel approach to sensing broadband radio frequency (RF) spectrum beyond the Nyquist limit based on photonic temporal channelization and compressive sensing is proposed. A spectrally-sparse RF signal with unknown frequencies is modulated onto a highly chirped optical pulse. An optical channelizer slices the modulated pulse spectrum, which is equivalent to temporally sampling the RF waveform thanks to the dispersion-induced wavelength-to-time mapping. This serial-to-parallel conversion avoids the use of a high-speed detector and digitizer. Furthermore, compressive sensing with optical random demodulation is achieved using a spatial light modulator, enabling the system to capture the wideband multi-tone RF signal with a sampling rate far lower than the Nyquist rate. It is demonstrated that the temporal channelization system with a channel spacing of 20 GHz achieves RF spectrum sensing with a high resolution of 196 MHz. With an equivalent sampling rate of only 25 GHz, a 50-GHz broadband two-tone RF signal can be captured and reconstructed by the system thanks to compressive sensing with a compression ratio of 4
Conservation laws arising in the study of forward-forward Mean-Field Games
We consider forward-forward Mean Field Game (MFG) models that arise in
numerical approximations of stationary MFGs. First, we establish a link between
these models and a class of hyperbolic conservation laws as well as certain
nonlinear wave equations. Second, we investigate existence and long-time
behavior of solutions for such models
Dressing approach to the nonvanishing boundary value problem for the AKNS hierarchy
We propose an approach to the nonvanishing boundary value problem for
integrable hierarchies based on the dressing method. Then we apply the method
to the AKNS hierarchy. The solutions are found by introducing appropriate
vertex operators that takes into account the boundary conditions.Comment: Published version Proc. Quantum Theory and Symmetries 7
(QTS7)(Prague, Czech Republic, 2011
Solution of the quantum harmonic oscillator plus a delta-function potential at the origin: The oddness of its even-parity solutions
We derive the energy levels associated with the even-parity wave functions of
the harmonic oscillator with an additional delta-function potential at the
origin. Our results bring to the attention of students a non-trivial and
analytical example of a modification of the usual harmonic oscillator
potential, with emphasis on the modification of the boundary conditions at the
origin. This problem calls the attention of the students to an inaccurate
statement in quantum mechanics textbooks often found in the context of solution
of the harmonic oscillator problem.Comment: 9 pages, 3 figure
The complex Sine-Gordon equation as a symmetry flow of the AKNS Hierarchy
It is shown how the complex sine-Gordon equation arises as a symmetry flow of
the AKNS hierarchy. The AKNS hierarchy is extended by the ``negative'' symmetry
flows forming the Borel loop algebra. The complex sine-Gordon and the vector
Nonlinear Schrodinger equations appear as lowest negative and second positive
flows within the extended hierarchy. This is fully analogous to the well-known
connection between the sine-Gordon and mKdV equations within the extended mKdV
hierarchy.
A general formalism for a Toda-like symmetry occupying the ``negative''
sector of sl(N) constrained KP hierarchy and giving rise to the negative Borel
sl(N) loop algebra is indicated.Comment: 8 pages, LaTeX, typos corrected, references update
T-Duality in 2-D Integrable Models
The non-conformal analog of abelian T-duality transformations relating pairs
of axial and vector integrable models from the non abelian affine Toda family
is constructed and studied in detail.Comment: 14 pages, Latex, v.2 misprints corrected, reference added, to appear
in J. Phys.
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