11,645 research outputs found
A note on the error estimate of the virtual element methods
This short note reports a new derivation of the optimal order of the a priori
error estimates for conforming virtual element methods (VEM) on 3D polyhedral
meshes based on an error equation. The geometric assumptions, which are
necessary for the optimal order of the conforming VEM error estimate in the
-seminorm, are relaxed for that in a bilinear form-induced energy norm
Probing Higgs Width and Top Quark Yukawa Coupling from and Productions
We demonstrate that four top-quark production is a powerful tool to constrain
the top Yukawa coupling. The constraint is robust in the sense that it does not
rely on the Higgs boson decay. Taking into account the projection of the
production by the ATLAS collaobration, we obtain a bound on Higgs
boson width, , at the 14 TeV LHC with an
integrated luminosity of . Increasing the luminosity to
yields
Transfer Adversarial Hashing for Hamming Space Retrieval
Hashing is widely applied to large-scale image retrieval due to the storage
and retrieval efficiency. Existing work on deep hashing assumes that the
database in the target domain is identically distributed with the training set
in the source domain. This paper relaxes this assumption to a transfer
retrieval setting, which allows the database and the training set to come from
different but relevant domains. However, the transfer retrieval setting will
introduce two technical difficulties: first, the hash model trained on the
source domain cannot work well on the target domain due to the large
distribution gap; second, the domain gap makes it difficult to concentrate the
database points to be within a small Hamming ball. As a consequence, transfer
retrieval performance within Hamming Radius 2 degrades significantly in
existing hashing methods. This paper presents Transfer Adversarial Hashing
(TAH), a new hybrid deep architecture that incorporates a pairwise
-distribution cross-entropy loss to learn concentrated hash codes and an
adversarial network to align the data distributions between the source and
target domains. TAH can generate compact transfer hash codes for efficient
image retrieval on both source and target domains. Comprehensive experiments
validate that TAH yields state of the art Hamming space retrieval performance
on standard datasets
A broad-band laser-driven double Fano system - photoelectron spectra
Fano profiles, with their asymmetric character, have many potential
applications in technology. The design of Fano profiles into optical systems
may create new nonlinear and switchable metamaterials, high-quality optical
waveguides, ultrasensitive media for chemical or biosensing etc. In this paper,
we consider an external field-driven double Fano model, in which, instead of
one autoionizing state, there are two discrete states embedded in one
continuum. We assume further that the external electromagnetic field can be
decomposed into two parts: a deterministic (or coherent) part and a randomly
fluctuating chaotic component, which is a \delta-correlated, Gaussian, Markov
and stationary process (white noise). This assumption corresponds to the case
of the real multimode laser operating without any correlation between the
modes. We solve a set of coupled stochastic integro-differential equations
involving the Fano model with two discrete levels. We derive an exact formula
by determining the photoelectron spectrum and compare it with the results
obtained in our previous papers
On dRGT massive gravity with degenerate reference metrics
In dRGT massive gravity, to get the equations of motion, the square root
tensor is assumed to be invertible in the variation of the action. However,
this condition can not be fulfilled when the reference metric is degenerate.
This implies that the resulting equations of motion might be different from the
case where the reference metric has full rank. In this paper, by generalizing
the Moore-Penrose inverse to the symmetric tensor on Lorentz manifolds, we get
the equations of motion of the theory with degenerate reference metric. It is
found that the equations of motion are a little bit different from those in the
non-degenerate cases. Based on the result of the equations of motion, for the
-dimensional solutions with the symmetry of -dimensional maximally
symmetric space, we prove a generalized Birkhoff theorem in the case where the
degenerate reference metric has rank , i.e., we show that the solutions must
be Schwarzschild-type or Nariai-Bertotti-Robinson-type under the assumptions.Comment: v1, Latex, 29 pages, no figures; v2, references added, typos
corrected, 30 page
Computer simulation of two-mode nonlinear quantum scissors
We present a simulation method allowing for modeling of quantum dynamics of
nonlinear quantum scissors' (NQS) systems. We concentrate on the two-mode model
involving two mutually interacting nonlinear quantum oscillators (Kerr
nonlinear coupler) excited by a series of ultra-short external coherent pulses.
We show that despite the simplicity of the method one can obtain non-trivial
results. In particular, we discuss and compare two cases of kicked nonlinear
coupler, showing that the quantum evolution of the system remains closed within
a two-qubit Hilbert space and can lead to maximally entangled states
generation
Black hole hair in higher dimensions
We study the property of matter in equilibrium with a static, spherically
symmetric black hole in D-dimensional spacetime. It requires this kind of
matter has an equation of state (\omega\equiv p_r/\rho=-1/(1+2kn), k,n\in
\mathbb{N}), which seems to be independent of D. However, when we associate
this with specific models, some interesting limits on space could be found:
(i)(D=2+2kn) while the black hole is surrounded by cosmic strings;
(ii)the black hole can be surrounded by linear dilaton field only in
4-dimensional spacetime. In both cases, D=4 is special.Comment: 8 page
Self-consistency in relativistic theory of infinite statistics fields
Infinite statistics in which all representations of the symmetric group can
occur is known as a special case of quon theory. Our previous work has built a
relativistic quantum field theory which allows interactions involving infinite
statistics particles. In this paper, a more detailed analysis of this theory is
available. Topics discussed include cluster decomposition, CPT symmetry and
renormalization.Comment: 7 page
Covariant versions of Margolus-Levitin Theorem
The Margolus-Levitin Theorem is a limitation on the minimal evolving time of
a quantum system from its initial state to its orthogonal state. It also
supplies a bound on the maximal operations or events can occur within a volume
of spacetime. We compare Margolus-Levitin Theorem with other form of limitation
on minimal evolving time, and present covariant versions of Margolus-Levitin
Theorem in special and general relativity respectively. The relation among
entropy bound, maximum information flow and computational limit are discussed,
by applying the covariant versions of Margolus-Levitin Theorem.Comment: 11 pages, 1 figure, revte
Multi-Adversarial Domain Adaptation
Recent advances in deep domain adaptation reveal that adversarial learning
can be embedded into deep networks to learn transferable features that reduce
distribution discrepancy between the source and target domains. Existing domain
adversarial adaptation methods based on single domain discriminator only align
the source and target data distributions without exploiting the complex
multimode structures. In this paper, we present a multi-adversarial domain
adaptation (MADA) approach, which captures multimode structures to enable
fine-grained alignment of different data distributions based on multiple domain
discriminators. The adaptation can be achieved by stochastic gradient descent
with the gradients computed by back-propagation in linear-time. Empirical
evidence demonstrates that the proposed model outperforms state of the art
methods on standard domain adaptation datasets.Comment: AAAI 2018 Oral. arXiv admin note: substantial text overlap with
arXiv:1705.10667, arXiv:1707.0790
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