5,718 research outputs found
Neural Face Editing with Intrinsic Image Disentangling
Traditional face editing methods often require a number of sophisticated and
task specific algorithms to be applied one after the other --- a process that
is tedious, fragile, and computationally intensive. In this paper, we propose
an end-to-end generative adversarial network that infers a face-specific
disentangled representation of intrinsic face properties, including shape (i.e.
normals), albedo, and lighting, and an alpha matte. We show that this network
can be trained on "in-the-wild" images by incorporating an in-network
physically-based image formation module and appropriate loss functions. Our
disentangling latent representation allows for semantically relevant edits,
where one aspect of facial appearance can be manipulated while keeping
orthogonal properties fixed, and we demonstrate its use for a number of facial
editing applications.Comment: CVPR 2017 ora
On the evaluation of quasi-periodic Green functions and wave-scattering at and around Rayleigh-Wood anomalies
This article presents full-spectrum, well-conditioned, Green-function methodologies for evaluation of scattering by general periodic structures, which remains applicable on a set of challenging singular configurations, usually called Rayleigh-Wood (RW) anomalies (at which the quasi-periodic Green function ceases to exist), where most existing quasi-periodic solvers break down. After reviewing a variety of existing fast-converging numerical procedures commonly used to compute the classical quasi-periodic Green-function, the present work explores the difficulties they present around RW-anomalies and introduces the concept of hybrid “spatial/spectral” representations. Such expressions allow both the modification of existing methods to obtain convergence at RW-anomalies as well as the application of a slight generalization of the Woodbury-Sherman-Morrison formulae together with a limiting procedure to bypass the singularities. (Although, for definiteness, the overall approach is applied to the scalar (acoustic) wave-scattering problem in the frequency domain, the approach can be extended in a straightforward manner to the harmonic Maxwell's and elasticity equations.) Ultimately, this thorough study of RW-anomalies yields fast and highly-accurate solvers, which are demonstrated with a variety of simulations of wave-scattering phenomena by arrays of particles, crossed impenetrable and penetrable diffraction gratings and other related structures. In particular, the methods developed in this article can be used to “upgrade” classical approaches, resulting in algorithms that are applicable throughout the spectrum, and it provides new methods for cases where previous approaches are either costly or fail altogether. In particular, it is suggested that the proposed shifted Green function approach may provide the only viable alternative for treatment of three-dimensional high-frequency configurations with either one or two directions of periodicity. A variety of computational examples are presented which demonstrate the flexibility of the overall approach
Linear superposition as a core theorem of quantum empiricism
Clarifying the nature of the quantum state is at the root of
the problems with insight into (counterintuitive) quantum postulates. We
provide a direct-and math-axiom free-empirical derivation of this object as an
element of a vector space. Establishing the linearity of this structure-quantum
superposition-is based on a set-theoretic creation of ensemble formations and
invokes the following three principia: quantum statics,
doctrine of a number in the physical theory, and
mathematization of matching the two observations with each
other; quantum invariance.
All of the constructs rest upon a formalization of the minimal experimental
entity: observed micro-event, detector click. This is sufficient for producing
the -numbers, axioms of linear vector space (superposition
principle), statistical mixtures of states, eigenstates and their spectra, and
non-commutativity of observables. No use is required of the concept of time. As
a result, the foundations of theory are liberated to a significant extent from
the issues associated with physical interpretations, philosophical exegeses,
and mathematical reconstruction of the entire quantum edifice.Comment: No figures. 64 pages; 68 pages(+4), overall substantial improvements;
70 pages(+2), further improvement
Construction of Field Algebras with Quantum Symmetry from Local Observables
It has been discussed earlier that ( weak quasi-) quantum groups allow for
conventional interpretation as internal symmetries in local quantum theory.
From general arguments and explicit examples their consistency with (braid-)
statistics and locality was established. This work addresses to the
reconstruction of quantum symmetries and algebras of field operators. For every
algebra \A of observables satisfying certain standard assumptions, an
appropriate quantum symmetry is found. Field operators are obtained which act
on a positive definite Hilbert space of states and transform covariantly under
the quantum symmetry. As a substitute for Bose/Fermi (anti-) commutation
relations, these fields are demonstrated to obey local braid relation.Comment: 50 pages, HUTMP 93-B33
Lectures on Loop Quantum Gravity
Quantum General Relativity (QGR), sometimes called Loop Quantum Gravity, has
matured over the past fifteen years to a mathematically rigorous candidate
quantum field theory of the gravitational field. The features that distinguish
it from other quantum gravity theories are 1) background independence and 2)
minimality of structures. Background independence means that this is a
non-perturbative approach in which one does not perturb around a given,
distinguished, classical background metric, rather arbitrary fluctuations are
allowed, thus precisely encoding the quantum version of Einstein's radical
perception that gravity is geometry. Minimality here means that one explores
the logical consequences of bringing together the two fundamental principles of
modern physics, namely general covariance and quantum theory, without adding
any experimentally unverified additional structures. The approach is purposely
conservative in order to systematically derive which basic principles of
physics have to be given up and must be replaced by more fundamental ones. QGR
unifies all presently known interactions in a new sense by quantum mechanically
implementing their common symmetry group, the four-dimensional diffeomorphism
group, which is almost completely broken in perturbative approaches. These
lectures offer a problem -- supported introduction to the subject.Comment: 90 pages, Latex, 18 figures, uses graphicx and pstricks for coloured
text and graphics, based on lectures given at the 271st WE Heraeus Seminar
``Aspects of Quantum Gravity: From Theory to Experimental Search'', Bad
Honnef, Germany, February 25th -- March 1st, to appear in Lecture Notes in
Physic
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