975 research outputs found
Charge Qubit Storage and Its Engineered Decoherence via Microwave Cavity
We study the entanglement of the superconducting charge qubit with the
quantized electromagnetic field in a microwave cavity. It can be controlled
dynamically by a classical external field threading the SQUID within the charge
qubit. Utilizing the controllable quantum entanglement, we can demonstrate the
dynamic process of the quantum storage of information carried by charge qubit.
On the other hand, based on this engineered quantum entanglement, we can also
demonstrate a progressive decoherence of charge qubit with quantum jump due to
the coupling with the cavity field in quasi-classical state.Comment: 6 pages, 4 figure
Decay process of quantum open system at finite-temperature
Starting from the formal solution to the Heisenberg equation, we revisit an
universal model for a quantum open system with a harmonic oscillator linearly
coupled to a boson bath. The analysis of the decay process for a Fock state and
a coherent state demonstrate that this method is very useful in dealing with
the problems in decay process of the open system. For finite temperature, the
calculations of the reduced density matrix and the mean excitation number for
the open system show that an initial coherent state will evolve into a
temperature-dependant coherent state after tracing over the bath variables.
Also in short-time limit, a temperature-dependant effective Hamiltonian for the
open system characterizes the decay process of the open system
Genetic diversity and phylogenetic relationships within Eucalyptus marginata (Myrtaceae)
The eucalypt species Eucalyptus marginata which is harvested for high quality timber comprises three subspecies recognized by morphological characters; E. marginata ssp. marginata, ssp. thalassica, and ssp. elegantella. Genetic diversity and phylogenetic relationships between the subspecies were examined using anonymous nuclear RFLP loci, with Eucalyptus staerei included as an outgroup in the phylogenetic analysis. The level of diversity within the nuclear genome was lower than that found in comparative studies with other eucalypts (A = 2. 7, H4 = 0.345). Most of the variation occurred with ill the populations (96. 9%, H4 = 0.334) The two populations sampled for each of ssp. thalassica and ssp. elegantella clustered together in the UPGMA analysis, however there was little differentiation between the three subspecies overall (D = 0.029). Eucalyptus marginata was clearly distinct from its closest relative E. staerei (0 = 0.16). There is little genetic support for the separation of the subspecies
Solution Of Wheeler-De Witt Equation, Potential Well And Tunnel Effect
This paper uses the relation of the cosmic scale factor and scalar field to
solve Wheeler-DeWitt equation, gives the tunnel effect of the cosmic scale
factor a and quantum potential well of scalar field, and makes it fit with the
physics of cosmic quantum birth. By solving Wheeler-DeWitt equation we achieve
a general probability distribution of the cosmic birth, and give the analysis
of cosmic quantum birth.Comment: 12 page
The Possibilist Transactional Interpretation and Relativity
A recent ontological variant of Cramer's Transactional Interpretation, called
"Possibilist Transactional Interpretation" or PTI, is extended to the
relativistic domain. The present interpretation clarifies the concept of
'absorption,' which plays a crucial role in TI (and in PTI). In particular, in
the relativistic domain, coupling amplitudes between fields are interpreted as
amplitudes for the generation of confirmation waves (CW) by a potential
absorber in response to offer waves (OW), whereas in the nonrelativistic
context CW are taken as generated with certainty. It is pointed out that
solving the measurement problem requires venturing into the relativistic domain
in which emissions and absorptions take place; nonrelativistic quantum
mechanics only applies to quanta considered as 'already in existence' (i.e.,
'free quanta'), and therefore cannot fully account for the phenomenon of
measurement, in which quanta are tied to sources and sinks.Comment: Final version with some minor corrections as published in Foundations
of Physics. This paper has significant overlap with Chapter 6 of my book on
the Transactional Interpretation, forthcoming from Cambridge University
Press:
http://www.cambridge.org/us/knowledge/isbn/item6860644/?site_locale=en_US
(Additional preview material is available at rekastner.wordpress.com)
Comments welcom
Torsion cycles as non-local magnetic sources in non-orientable spaces
Non-orientable spaces can appear to carry net magnetic charge, even in the
absence of magnetic sources. It is shown that this effect can be understood as
a physical manifestation of the existence of torsion cycles of codimension one
in the homology of space.Comment: 17 pages, 4 figure
Action at a distance as a full-value solution of Maxwell equations: basis and application of separated potential's method
The inadequacy of Li\'{e}nard-Wiechert potentials is demonstrated as one of
the examples related to the inconsistency of the conventional classical
electrodynamics. The insufficiency of the Faraday-Maxwell concept to describe
the whole electromagnetic phenomena and the incompleteness of a set of
solutions of Maxwell equations are discussed and mathematically proved. Reasons
of the introduction of the so-called ``electrodynamics dualism concept"
(simultaneous coexistence of instantaneous Newton long-range and
Faraday-Maxwell short-range interactions) have been displayed. It is strictly
shown that the new concept presents itself as the direct consequence of the
complete set of Maxwell equations and makes it possible to consider classical
electrodynamics as a self-consistent and complete theory, devoid of inward
contradictions. In the framework of the new approach, all main concepts of
classical electrodynamics are reconsidered. In particular, a limited class of
motion is revealed when accelerated charges do not radiate electromagnetic
field.Comment: ReVTeX file, 24pp. Small corrections which do not have influence
results of the paper. Journal reference is adde
Cluster states in nuclei as representations of a U(n+1) group
We propose a description of cluster states in nuclei in terms of
representations of unitary algebras U(n+1), where n is the number of space
degrees of freedom. Within this framework, a variety of situations including
both vibrational and rotational spectra, soft and rigid configurations,
identical and non-identical constituents can be described. As an example, we
show how the method can be used to study alpha-clustering configurations in 12C
with point group symmetry D(3h).Comment: 5 pages, 2 figures, Phys. Rev. C, in pres
Wormhole phase in the RST model
We show that the RST model describing the exactly soluble black hole model
can have a dynamical wormhole solution along with an appropriate boundary
condition. The necessary exotic matter which is usually negative energy density
is remarkably produced by the quantization of the infalling matter fields. Then
the asymptotic geometry in the past is two-dimensional anti-de Sitter(AdS),
which implies the exotic matter is negative. As time goes on, the wormhole
eventually evolves into the black hole and its Hawking radiation appears. The
throat of the static RST wormhole is lower-bounded but in the presence of
infalling matter it collapses to a black hole.Comment: v1. REVTeX3, 12 pages and 1 figure; v2. JHEP3, 10 pages and 1 figure,
version published in JHE
Can a wormhole generate electromagnetic field?
We have considered the possibility of a slowly rotating wormhole surrounded
by a cloud of charged particles. Due to slow rotation of the wormhole, the
charged particles are dragged thereby producing an electromagnetic field. We
have determined the strength of this electromagnetic field and the
corresponding flux of radiation.Comment: 9 pages, typos fixe
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