27,926 research outputs found
Informed consent and the transmission of sexual disease: Dadson Revivified
This article examines the impact of the decisions in R v Dica (2004) and R v Konzani (2005) on the extent of the defence of consent. As well as analysing the impact of the decisions on the extent of the defence where a defendant faces criminal liability for the transmission of sexual disease, it also considers and examines the wider issue of whether the presence or absence of consent forms part of the actus reus of the relevant assault offence or whether it is a separate and independent element that stands outside of the conduct component of the offence. It is argued that recent developments have given insufficient consideration to accepted doctrine and revived much criticised principles by focusing on unknown circumstances of justification rather than the defendant's state of knowledge and mind
Point interactions in acoustics: one dimensional models
A one dimensional system made up of a compressible fluid and several
mechanical oscillators, coupled to the acoustic field in the fluid, is analyzed
for different settings of the oscillators array. The dynamical models are
formulated in terms of singular perturbations of the decoupled dynamics of the
acoustic field and the mechanical oscillators. Detailed spectral properties of
the generators of the dynamics are given for each model we consider. In the
case of a periodic array of mechanical oscillators it is shown that the energy
spectrum presents a band structure.Comment: revised version, 30 pages, 2 figure
Path-Integral Formulation of Pseudo-Hermitian Quantum Mechanics and the Role of the Metric Operator
We provide a careful analysis of the generating functional in the path
integral formulation of pseudo-Hermitian and in particular PT-symmetric quantum
mechanics and show how the metric operator enters the expression for the
generating functional.Comment: Published version, 4 page
On separability of quantum states and the violation of Bell-type inequalities
In contrast to the wide-spread opinion that any separable quantum state
satisfies every classical probabilistic constraint, we present a simple example
where a separable quantum state does not satisfy the original Bell inequality
although the latter inequality, in its perfect correlation form, is valid for
all joint classical measurements. In a very general setting, we discuss
inequalities for joint experiments upon a bipartite quantum system in a
separable state. We derive quantum analogues of the original Bell inequality
and specify the conditions sufficient for a separable state to satisfy the
original Bell inequality. We introduce the extended CHSH inequality and prove
that, for any separable quantum state, this inequality holds for a variety of
linear combinations.Comment: 13 pages, extended versio
Finite lifetime eigenfunctions of coupled systems of harmonic oscillators
We find a Hermite-type basis for which the eigenvalue problem associated to
the operator acting on becomes a three-terms recurrence. Here and are two constant
positive definite matrices with no other restriction. Our main result provides
an explicit characterization of the eigenvectors of that lie in the
span of the first four elements of this basis when .Comment: 11 pages, 1 figure. Some typos where corrected in this new versio
A Composite Genome Approach to Identify Phylogenetically Informative Data from Next-Generation Sequencing
We have developed a novel method to rapidly obtain homologous genomic data
for phylogenetics directly from next-generation sequencing reads without the
use of a reference genome. This software, called SISRS, avoids the time
consuming steps of de novo whole genome assembly, genome-genome alignment, and
annotation. For simulations SISRS is able to identify large numbers of loci
containing variable sites with phylogenetic signal. For genomic data from apes,
SISRS identified thousands of variable sites, from which we produced an
accurate phylogeny. Finally, we used SISRS to identify phylogenetic markers
that we used to estimate the phylogeny of placental mammals. We recovered
phylogenies from multiple datasets that were consistent with previous
conflicting estimates of the relationships among mammals. SISRS is open source
and freely available at https://github.com/rachelss/SISRS.Comment: 12 pages plus36 figures, 1 supplementary table, 3 supplementary
figure
A Physical Realization of the Generalized PT-, C-, and CPT-Symmetries and the Position Operator for Klein-Gordon Fields
Generalized parity (P), time-reversal (T), and charge-conjugation
(C)operators were initially definedin the study of the pseudo-Hermitian
Hamiltonians. We construct a concrete realization of these operators for
Klein-Gordon fields and show that in this realization PT and C operators
respectively correspond to the ordinary time-reversal and charge-grading
operations. Furthermore, we present a complete description of the quantum
mechanics of Klein-Gordon fields that is based on the construction of a Hilbert
space with a relativistically invariant, positive-definite, and conserved inner
product. In particular we offer a natural construction of a position operator
and the corresponding localized and coherent states. The restriction of this
position operator to the positive-frequency fields coincides with the
Newton-Wigner operator. Our approach does not rely on the conventional
restriction to positive-frequency fields. Yet it provides a consistent quantum
mechanical description of Klein-Gordon fields with a genuine probabilistic
interpretation.Comment: 20 pages, published versio
RAT J0455+1305: A rare hybrid pulsating subdwarf B star
We present results on the second-faintest pulsating subdwarf B (sdB) star
known, RAT J0455+1305, derived from photometric data obtained in 2009. It shows
both short and long periods oscillations, theoretically assigned as pressure
and gravity modes. We identify six short-period frequencies (with one being a
combination) and six long-period frequencies. This star is the fourth hybrid
sdB star discovered so far which makes it of special interest as each type of
mode probes a different part of the star. This star is similar to the sdB
hybrid pulsator Balloon 090100001 in that it exhibits short-period mode
groupings, which can be used to identify pulsation parameters and constrain
theoretical models.Comment: published in MNRA
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