55,174 research outputs found
Quantum States Allowing Minimum Uncertainty Product of angular position and momentum
We provide necessary and sufficient conditions for states to have an
arbitrarily small uncertainty product of the azimuthal angle and its
canonical moment . We illustrate our results with analytical examples
Industrial Illegitimacy and Negative Externalities: the Case of the Illinois Livestock Industry
An industry's legitimacy depends on stakeholders' perceptions and assessments of the appropriateness of its behavior across a wide array of settings. While products and services may be highly valued, and in some cases essential, business externalities serve as a powerful counterforce undermining legitimacy. The work draws on the theory of industrial legitimacy and employs a taxonomy of four different legitimacy sub components; pragmatic, regulative, normative, and cognitive. The paper identifies how externalities affect an industry's legitimacy and the relative contribution of each sub component. The research then empirically tests the theory using the case of the Illinois livestock industry.Livestock Production/Industries,
Gribov ambiguities at the Landau -- maximal Abelian interpolating gauge
In a previous work, we presented a new method to account for the Gribov
ambiguities in non-Abelian gauge theories. The method consists on the
introduction of an extra constraint which directly eliminates the infinitesimal
Gribov copies without the usual geometric approach. Such strategy allows to
treat gauges with non-hermitian Faddeev-Popov operator. In this work, we apply
this method to a gauge which interpolates among the Landau and maximal Abelian
gauges. The result is a local and power counting renormalizable action, free of
infinitesimal Gribov copies. Moreover, the interpolating tree-level gluon
propagator is derived.Comment: Several changes: figures removed, typos corrected and discussions
included. 24 pages, to appear in EPJ
Status of background-independent coarse-graining in tensor models for quantum gravity
A background-independent route towards a universal continuum limit in
discrete models of quantum gravity proceeds through a background-independent
form of coarse graining. This review provides a pedagogical introduction to the
conceptual ideas underlying the use of the number of degrees of freedom as a
scale for a Renormalization Group flow. We focus on tensor models, for which we
explain how the tensor size serves as the scale for a background-independent
coarse-graining flow. This flow provides a new probe of a universal continuum
limit in tensor models. We review the development and setup of this tool and
summarize results in the 2- and 3-dimensional case. Moreover, we provide a
step-by-step guide to the practical implementation of these ideas and tools by
deriving the flow of couplings in a rank-4-tensor model. We discuss the
phenomenon of dimensional reduction in these models and find tentative first
hints for an interacting fixed point with potential relevance for the continuum
limit in four-dimensional quantum gravity.Comment: 28 pages, Review prepared for the special issue "Progress in Group
Field Theory and Related Quantum Gravity Formalisms" in "Universe
Speech Recognition by Composition of Weighted Finite Automata
We present a general framework based on weighted finite automata and weighted
finite-state transducers for describing and implementing speech recognizers.
The framework allows us to represent uniformly the information sources and data
structures used in recognition, including context-dependent units,
pronunciation dictionaries, language models and lattices. Furthermore, general
but efficient algorithms can used for combining information sources in actual
recognizers and for optimizing their application. In particular, a single
composition algorithm is used both to combine in advance information sources
such as language models and dictionaries, and to combine acoustic observations
and information sources dynamically during recognition.Comment: 24 pages, uses psfig.st
On the elimination of infinitesimal Gribov ambiguities in non-Abelian gauge theories
An alternative method to account for the Gribov ambiguities in gauge theories
is presented. It is shown that, to eliminate Gribov ambiguities, at
infinitesimal level, it is required to break the BRST symmetry in a soft
manner. This can be done by introducing a suitable extra constraint that
eliminates the infinitesimal Gribov copies. It is shown that the present
approach is consistent with the well established known cases in the literature,
i.e., the Landau and maximal Abelian gauges. The method is valid for gauges
depending exclusively on the gauge field and is restricted to classical level.
However, occasionally, we deal with quantum aspects of the technique, which are
used to improve the results.Comment: 29 pp. No figures. Discussions added. Final version to appear in EPJ
A non-perturbative study of matter field propagators in Euclidean Yang-Mills theory in linear covariant, Curci-Ferrari and maximal Abelian gauges
In this work, we study the propagators of matter fields within the framework
of the Refined Gribov-Zwanziger theory, which takes into account the effects of
the Gribov copies in the gauge-fixing quantization procedure of Yang-Mills
theory. In full analogy with the pure gluon sector of the Refined
Gribov-Zwanziger action, a non-local long-range term in the inverse of the
Faddeev-Popov operator is added in the matter sector. Making use of the recent
BRST invariant formulation of the Gribov-Zwanziger framework achieved in [Capri
et al 2016], the propagators of scalar and quark fields in the adjoint and
fundamental representations of the gauge group are worked out explicitly in the
linear covariant, Curci-Ferrari and maximal Abelian gauges. Whenever lattice
data are available, our results exhibit good qualitative agreement.Comment: 27 pages, no figures; V2, minor modifications, to appear in EPJ
- …