6,743 research outputs found
Quantum quenches and off-equilibrium dynamical transition in the infinite-dimensional Bose-Hubbard model
We study the off-equilibrium dynamics of the infinite dimensional Bose
Hubbard Model after a quantum quench. The dynamics can be analyzed exactly by
mapping it to an effective Newtonian evolution. For integer filling, we find a
dynamical transition separating regimes of small and large quantum quenches
starting from the superfluid state. This transition is very similar to the one
found for the fermionic Hubbard model by mean field approximations.Comment: 5 pages, 5 figure
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Adverse Childhood Experiences in Medical Students: Implications for Wellness.
ObjectiveThe primary purpose of the study was to assess the prevalence of adverse childhood experiences (ACEs) in a cohort of third-year medical students and characterize their childhood protective factors.MethodsThe authors developed a web-based anonymous survey distributed to all third-year medical students in one school (N = 98). The survey included the 10-item ACE Study questionnaire, a list of childhood protective factors (CPF) and questions to assess students' perception of the impact of ACEs on their physical and mental health. The medical school's IRB approved the student survey as an exempt study. The authors computed descriptive and comparative statistical analyses.ResultsEighty-six of 98 students responded (88% response rate). Forty-four students (51%) reported at least one ACE exposure and 10 (12%) reported ≥ 4 exposures. The latter were all female. The average difference in the ACE score between male and female medical students was - 1.1 (independent t test with unequal variances t(57.7) = - 2.82, P = .007). Students with an ACE score of ≥ 4 were significantly more likely to report a moderate or significant effect on their mental health, compared with students with scores ≤ 3 (chi-square test, P = < .0001). Most students reported high levels of CPF (median score = 13 of a maximum score = 14). ACEs and CPF were inversely associated (Pearson correlation = - 0.32, P = .003).ConclusionsA sizeable minority of medical students reported exposure to multiple ACEs. If replicated, findings suggest a significant vulnerability of these medical students to health risk behaviors and physical and mental health problems during training and future medical practice
Recent measurements of CP violation at the B factories
Recent measurements of time dependent CP asymmetries at the B factories have
led to substantial progress in our understanding of CP violation. In this
article, I review some of these experimental results and discuss their
implications in the Standard Model and their sensitivity to New Physics.Comment: 17 pages, 13 figures, to be published in Modern Physics Letters A. To
be published in Modern Physics Letters
Dynamical transitions and quantum quenches in mean-field models
We develop a generic method to compute the dynamics induced by quenches in
completely connected quantum systems. These models are expected to provide a
mean-field description at least of the short time dynamics of finite
dimensional system. We apply our method to the Bose-Hubbard model, to a
generalized Jaynes-Cummings model, and to the Ising model in a transverse
field. We find that the quantum evolution can be mapped onto a classical
effective dynamics, which involves only a few intensive observables. For some
special parameters of the quench, peculiar dynamical transitions occur. They
result from singularities of the classical effective dynamics and are
reminiscent of the transition recently found in the fermionic Hubbard model.
Finally, we discuss the generality of our results and possible extensions
Data acquisition electronics and reconstruction software for directional detection of Dark Matter with MIMAC
Directional detection of galactic Dark Matter requires 3D reconstruction of
low energy nuclear recoils tracks. A dedicated acquisition electronics with
auto triggering feature and a real time track reconstruction software have been
developed within the framework of the MIMAC project of detector. This
auto-triggered acquisition electronic uses embedded processing to reduce data
transfer to its useful part only, i.e. decoded coordinates of hit tracks and
corresponding energy measurements. An acquisition software with on-line
monitoring and 3D track reconstruction is also presented.Comment: 17 pages, 12 figure
Physics results from BABAR and prospects
The BABAR experiment has been taking data since about one year. Physics
results, complementary to those described by G.Sciolla elsewhere in these
Proceedings, are presented: various measurements of the neutral and charged B
mesons lifetimes, the B^0 mixing frequency, the mistag fractions, and the B -->
D_s^(*) X and B^0 --> D_s^(*)+ D^* branching ratios. Some prospects for the
close future are shown. All the numbers given here are preliminary.Comment: 12 pages, 12 postscript figures, contributed proceedings of the
International Conference On CP Violation Physics, 9/18-22/2000, Ferrara,
Ital
Prospects for collider searches for dark matter with heavy quarks
We present projections for future collider searches for dark matter produced
in association with bottom or top quarks. Such production channels give rise to
final states with missing transverse energy and one or more b-jets. Limits are
given assuming an effective scalar operator coupling dark matter to quarks,
where the dedicated analysis discussed here improves significantly over a
generic monojet analysis. We give updated results for an anticipated
high-luminosity LHC run at 14 TeV and for a 33 TeV hadron collider
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