544 research outputs found
Entanglement, Superselection Rules and Supersymmetric Quantum Mechanics
In this paper we show that the energy eigenstates of supersymmetric quantum
mechanics (SUSYQM) with non definite "fermion" number are entangled states.
They are "physical states" of the model provided that observables with odd
number of spin variables are allowed in the theory like it happens in the
Jaynes-Cummings model. Those states generalize the so called "spin spring"
states of the Jaynes-Cummings model which have played an important role in the
study of entanglement.Comment: 2 words added in the title, a section (IV) added in the text, a new
author joined the projec
Universal Hidden Supersymmetry in Classical Mechanics and its Local Extension
We review here a path-integral approach to classical mechanics and explore
the geometrical meaning of this construction. In particular we bring to light a
universal hidden BRS invariance and its geometrical relevance for the Cartan
calculus on symplectic manifolds. Together with this BRS invariance we also
show the presence of a universal hidden genuine non-relativistic supersymmetry.
In an attempt to understand its geometry we make this susy local following the
analogous construction done for the supersymmetric quantum mechanics of Witten.Comment: 6 pages, latex, Volkov Memorial Proceeding
Quantum mechanics over a q-deformed (0+1)-dimensional superspace
We built up a explicit realization of (0+1)-dimensional q-deformed superspace
coordinates as operators on standard superspace. A q-generalization of
supersymmetric transformations is obtained, enabling us to introduce scalar
superfields and a q-supersymmetric action. We consider a functional integral
based on this action. Integration is implemented, at the level of the
coordinates and at the level of the fields, as traces over the corresponding
representation spaces. Evaluation of these traces lead us to standard
functional integrals. The generation of a mass term for the fermion field
leads, at this level, to an explicitely broken version of supersymmetric
quantum mechanics.Comment: 11 pages, Late
The Response Field and the Saddle Points of Quantum Mechanical Path Integrals
In quantum statistical mechanics, Moyal's equation governs the time evolution
of Wigner functions and of more general Weyl symbols that represent the density
matrix of arbitrary mixed states. A formal solution to Moyal's equation is
given by Marinov's path integral. In this paper we demonstrate that this path
integral can be regarded as the natural link between several conceptual,
geometric, and dynamical issues in quantum mechanics. A unifying perspective is
achieved by highlighting the pivotal role which the response field, one of the
integration variables in Marinov's integral, plays for pure states even. The
discussion focuses on how the integral's semiclassical approximation relates to
its strictly classical limit; unlike for Feynman type path integrals, the
latter is well defined in the Marinov case. The topics covered include a random
force representation of Marinov's integral based upon the concept of "Airy
averaging", a related discussion of positivity-violating Wigner functions
describing tunneling processes, and the role of the response field in
maintaining quantum coherence and enabling interference phenomena. The double
slit experiment for electrons and the Bohm-Aharonov effect are analyzed as
illustrative examples. Furthermore, a surprising relationship between the
instantons of the Marinov path integral over an analytically continued ("Wick
rotated") response field, and the complex instantons of Feynman-type integrals
is found. The latter play a prominent role in recent work towards a
Picard-Lefschetz theory applicable to oscillatory path integrals and the
resurgence program.Comment: 58 page
Is classical reality completely deterministic?
The concept of determinism for a classical system is interpreted as the
requirement that the solution to the Cauchy problem for the equations of motion
governing this system be unique. This requirement is generally assumed to hold
for all autonomous classical systems. We give counterexamples of this view. Our
analysis of classical electrodynamics in a world with one temporal and one
spatial dimension shows that the solution to the Cauchy problem with the
initial conditions of a particular type is not unique. Therefore, random
behavior of closed classical systems is indeed possible. This finding provides
a qualitative explanation of how classical strings can split. We propose a
modified path integral formulation of classical mechanics to include
indeterministic systems.Comment: Replace the paper with a revised versio
Semiclassical Gauge Theories
We study the properties of a non-abelian gauge theory subjected to a gauge
invariant constraint given by the classical equations of motion. The constraint
is not imposed by hand, but appears naturally when we study a particular type
of local gauge transformations. In this way, all standard techniques to treat
gauge theories are available. We will show that this theory lives at one-loop.
Also this model retains some quantum characteristic of the usual non-abelian
gauge theories as asymptotic freedom.Comment: 15 pages, Latex. Added reference. Small changes in abstract and
introduction.Additional appendi
RETURN TO WORK IN ITALIAN CANCER SURVIVORS: THE INNOVATIVE SOCIAL-HEALTH CARE NETWORK
The Local Health Authority of Reggio Emilia, supported by the Manodori Foundation, decided to implement this innovative social-health care pathway that was created together with other 14 organizations in the Province of Reggio Emilia: they are Associations, labor union, training institutions, social cooperatives, and so on… Together, we created a network to address the need to go back to work of cancer patients.
What happens to the working age patients with cancer in Reggio Emilia?
First of all first of all the HCPs who meet the patients for diagnostic or curative reasons ask for information about the work situation. On the basis of this very first information collected, if the patient is judged at risk to lose the job he is referred to the network hub of UNA MANO: the Informa-salute service.
Here, a Nurse, together with other trained personnel, make the first true assessment of the risk to lose the job. If the patients is judged at low risk, he still receive information regarding… If the patient is judged at risk to lose the job, he is sent to the OT that make a deep, second level of assessment. After this, if the risk is confirmed as moderate, the patients will received a personalized intervention targeted to…
If the risk is judged very high, or the patient as already lost the job, the social part of the network is activated to implement a personalized intervention targeted to
Hot-water treatment of dormant grape cuttings: Its effects on Agrobacterium tumefaciens and on grafting and growth of vine
Hot-water treatment (50°C for 20-30 min) was carried out to confirm its efficacy in eradicating Agrobacterium tumefaciens biovar 3 (AT3) in symptomless grape cuttings.After the forcing period, analyses of callus from cuttings of grape cvs Albana, Lambrusco Grasparossa, Rulander and Fortana, and from their graft combinations with the rootstocks 420A, 41B, 5BB and 1103P, revealed the low infection level in the grape material used. Dormant scion and rootstock cuttings treated identically in the U.S. gave similar results. Despite this, it was possible to confirm the efficacy of thermotherapy in eradicating the pathogen.An assessment was also made of the effect of treatment on growth parameters of grafted vines in the greenhouse and after 8 months in a field nursery. The effect of hot-water treatment on the vitality and growth of vines varied with the different scion-rootstock combinations. Treatment did not generally have detrimental effects on vitality; there were some negative effects on graft-take. The number and length of canes, as well as the diameter of the trunks, increased in most instances.The treatments and times usually did not affect bud survival and, in most cases, increased the level of callus formation at the base of cuttings.
Ruthenacarborane and Quinoline: A Promising Combination for the Treatment of Brain Tumors
Gliomas and glioblastomas are very aggressive forms of brain tumors, prone to the development of a multitude of resistance mechanisms to therapeutic treatments, including cytoprotective autophagy. In this work, we investigated the role and mechanism of action of the combination of a ruthenacarborane derivative with 8-hydroxyquinoline (8-HQ), linked via an ester bond (complex 2), in rat astrocytoma C6 and human glioma U251 cells, in comparison with the two compounds alone, i.e., the free carboxylic acid (complex 1) and 8-HQ, and their non-covalent combination ([1 + 8-HQ], in 1:1 molar ratio). We found that only complex 2 was able to significantly affect cellular viability in glioma U251 cells (IC50 11.4 ÎĽM) via inhibition of the autophagic machinery, most likely acting at the early stages of the autophagic cascade. Contrary to 8-HQ alone, complex 2 was also able to impair cellular viability under conditions of glucose deprivation. We thus suggest different mechanisms of action of ruthenacarborane complex 2 than purely organic quinoline-based drugs, making complex 2 a very attractive candidate for evading the known resistances of brain tumors to chloroquine-based therapies
Zwitters: particles between quantum and classical
We describe both quantum particles and classical particles in terms of a
classical statistical ensemble, characterized by a probability distribution in
phase space. By use of a wave function in phase space both can be treated in
the same quantum formalism. The different dynamics of quantum and classical
particles resides then only from different evolution equations for the
probability distribution. Quantum particles are characterized by a specific
choice of observables and time evolution of the probability density. All
relations for a quantum particle in a potential, including interference and
tunneling, can be described in terms of the classical probability distribution.
We formulate the concept of zwitters - particles for which the time evolution
interpolates between quantum and classical particles. Experiments can test a
small parameter which quantifies possible deviations from quantum mechanics.Comment: extended discussion of possible realizations of zwitters, including
macroscopic droplets or BEC condensate
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