8,060 research outputs found
Demystifying “Pornography”: Tailoring Special Release Conditions Concerning Pornography and Sexually Oriented Expression
[Excerpt] “This article examines the design of special release conditions and the problems that arise when such conditions do not comport with constitutional standards. Part I provides a general overview of the First Amendment issues that often arise with respect to special release conditions. Part II discusses the current state of the law and classifies the types of bans defendants have encountered in supervised release conditions. Part III explains the factors that are frequently considered in assessing the validity of special release conditions, and Part IV suggests a new approach for evaluating the constitutionality of special release conditions. The article concludes by endorsing constitutionally permissible tailoring for release conditions and by encouraging courts to interpret these conditions with careful attention to the individual defendant’s situation.
Entanglement sudden death and sudden birth in two uncoupled spins
We investigate the entanglement evolution of two qubits interacting with a
common environment trough an Heisenberg XX mechanism. We reveal the possibility
of realizing the phenomenon of entanglement sudden death as well as the
entanglement sudden birth acting on the environment. Such analysis is of
maximal interest at the light of the large applications that spin systems have
in quantum information theory
Sensitivity of Measurement-Based Purification Processes to Inner Interactions
The sensitivity of a repeated measurement-based purification scheme to
additional undesired couplings is analyzed, focusing on the very simple and
archetypical system consisting of two two-level systems interacting with a
repeatedly measured one. Several regimes are considered and in the strong
coupling (i.e., when the coupling constant of the undesired interaction is very
large) the occurrence of a quantum Zeno effect is proven to dramatically
jeopardize the efficiency of the purification process.Comment: 12 pages, 6 figure
Derivative markets and competitiveness
Swaps (Finance) ; Futures ; Foreign exchange
A criterion for entanglement in two two-level systems
We prove a necessary and sufficient condition for the occurrence of
entanglement in two two-level systems, simple enough to be of experimental
interest. Our results are illustrated in the context of a spin star system
analyzing the exact entanglement evolution of the central couple of spins.Comment: 4 pages, Submitted to Physical Review Letter
Loss induced collective subradiant Dicke behaviour in a multiatom sample
The exact dynamics of two-level atoms coupled to a common electromagnetic
bath and closely located inside a lossy cavity is reported. Stationary
radiation trapping effects are found and very transparently interpreted in the
context of our approach. We prove that initially injecting one excitation only
in the atoms-cavity system, loss mechanisms asymptotically drive the matter
sample toward a long-lived collective subradiant Dicke state. The role played
by the closeness of the atoms with respect to such a cooperative behavior
is brought to light and carefully discussed.Comment: 14 pages, 6 figures, submitted to EPJ
Quantum Phase Transitions and Heat Capacity in a two-atoms Bose-Hubbard Model
We show that a two-atoms Bose-Hubbard model exhibits three different phases
in the behavior of thermal entanglement in its parameter space. These phases
are demonstrated to be traceable back to the existence of quantum phase
transitions in the same system. Significant similarities between the behaviors
of thermal entanglement and heat capacity in the parameter space are brought to
light thus allowing to interpret the occurrence and the meaning of all these
three phases.Comment: 6 pages, 3 figure
Revealing non-classical behaviours in the oscillatory motion of a trapped ion
The possibility of revealing non-classical behaviours in the dynamics of a
trapped ion via measurements of the mean value of suitable operators is
reported. In particular we focus on the manifestation known as `` Parity
Effect\rq\rq which may be observed \emph{directly measuring} the expectation
value of an appropriate correlation operator. The experimental feasibility of
our proposal is discussed.Comment: 5 pages, 2 figure
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