283 research outputs found
Unsharp Quantum Reality
The positive operator (valued) measures (POMs) allow one to generalize the notion of observable beyond the traditional one based on projection valued measures (PVMs). Here, we argue that this generalized conception of observable enables a consistent notion of unsharp reality and with it an adequate concept of joint properties. A sharp or unsharp property manifests itself as an element of sharp or unsharp reality by its tendency to become actual or to actualize a specific measurement outcome. This actualization tendency-or potentiality-of a property is quantified by the associated quantum probability. The resulting single-case interpretation of probability as a degree of reality will be explained in detail and its role in addressing the tensions between quantum and classical accounts of the physical world will be elucidated. It will be shown that potentiality can be viewed as a causal agency that evolves in a well-defined way
Sharp and fuzzy observables on effect algebras
Observables on effect algebras and their fuzzy versions obtained by means of
confidence measures (Markov kernels) are studied. It is shown that, on effect
algebras with the (E)-property, given an observable and a confidence measure,
there exists a fuzzy version of the observable. Ordering of observables
according to their fuzzy properties is introduced, and some minimality
conditions with respect to this ordering are found. Applications of some
results of classical theory of experiments are considered.Comment: 23 page
Extending scientific computing system with structural quantum programming capabilities
We present a basic high-level structures used for developing quantum
programming languages. The presented structures are commonly used in many
existing quantum programming languages and we use quantum pseudo-code based on
QCL quantum programming language to describe them. We also present the
implementation of introduced structures in GNU Octave language for scientific
computing. Procedures used in the implementation are available as a package
quantum-octave, providing a library of functions, which facilitates the
simulation of quantum computing. This package allows also to incorporate
high-level programming concepts into the simulation in GNU Octave and Matlab.
As such it connects features unique for high-level quantum programming
languages, with the full palette of efficient computational routines commonly
available in modern scientific computing systems. To present the major features
of the described package we provide the implementation of selected quantum
algorithms. We also show how quantum errors can be taken into account during
the simulation of quantum algorithms using quantum-octave package. This is
possible thanks to the ability to operate on density matrices
BIOLOGICAL, BEHAVIORAL, AND PSYCHOSOCIAL ATTRIBUTES OF INDIVIDUALS WITH COPD
The purpose of this dissertation was to evaluate the biological, behavioral, and psychosocial attributes of individuals diagnosed with chronic obstructive pulmonary disease (COPD). Specific aims were to: 1) explore the predictive power of spirometry measures for event-free survival in patients with heart failure and suspected COPD, focusing on the differences in survival between those with and without airflow limitation; 2) examine the psychometric properties of the Multidimensional Scale of Perceived Social Support (MSPSS) in patients with concomitant COPD and heart failure; and 3) test the efficacy of a theory-based, multidimensional, self-care educational intervention using an eHealth platform on measures of symptom severity and variability, anxiety and depressive symptoms, perceived self-care ability, perceived self-care adherence, and selfcare information needs (knowledge) in a sample of adult patients with stable COPD.
Specific aim one was addressed by evaluation of the predictive power of spirometry measures (forced expiratory volume/second [FEV1], forced vital capacity [FVC], and the ratio of FEV1/FVC) for event-free time to combined hospitalization/mortality after controlling for clinical and sociodemographic variables. This analysis revealed that those patients with airflow limitation were 2.2 times more likely to experience hospitalization/mortality compared to those without airflow limitation. The second specific aim was addressed with a psychometric evaluation of the Multidimensional Scale of Perceived Social support (MSPSS) which included determination of internal consistency reliability, the factor structure and construct validity by hypothesis testing in participants with comorbid COPD and heart failure. The MSPSS was a valid and reliable instrument to measure perceived social support in patients with comorbid COPD and heart failure. The third specific aim was addressed by a trial of an eHealth educational intervention in participants with COPD (N = 20). This intervention resulted in significant change in symptom severity evaluation in patients categorized as having medium symptom severity for the following symptoms: distress due to cough, chest tightness, dyspnea with activity and fatigue; these symptoms were perceived as more severe in the intervention period. Anxiety, depressive symptoms and perceived self-care ability were unchanged; however, perceived self-care adherence scores improved, and knowledge needs were significantly reduced after the intervention
Calculation of atomic spontaneous emission rate in 1D finite photonic crystal with defects
We derive the expression for spontaneous emission rate in finite
one-dimensional photonic crystal with arbitrary defects using the effective
resonator model to describe electromagnetic field distributions in the
structure. We obtain explicit formulas for contributions of different types of
modes, i.e. radiation, substrate and guided modes. Formal calculations are
illustrated with a few numerical examples, which demonstrate that the
application of effective resonator model simplifies interpretation of results.Comment: Cent. Eur. J. Phys, in pres
Complete positivity of nonlinear evolution: A case study
Simple Hartree-type equations lead to dynamics of a subsystem that is not
completely positive in the sense accepted in mathematical literature. In the
linear case this would imply that negative probabilities have to appear for
some system that contains the subsystem in question. In the nonlinear case this
does not happen because the mathematical definition is physically unfitting as
shown on a concrete example.Comment: extended version, 3 appendices added (on mixed states, projection
postulate, nonlocality), to be published in Phys. Rev.
Nonlinear Quantum Mechanics at the Planck Scale
I argue that the linearity of quantum mechanics is an emergent feature at the
Planck scale, along with the manifold structure of space-time. In this regime
the usual causality violation objections to nonlinearity do not apply, and
nonlinear effects can be of comparable magnitude to the linear ones and still
be highly suppressed at low energies. This can offer alternative approaches to
quantum gravity and to the evolution of the early universe.Comment: Talk given at the International Quantum Structures 2004 meeting, 16
pages LaTe
Oral anticancer agents: Presenting new challenges for family caregivers of patients with cancer
Attendees will learn the current state of the science on the new challenges that family caregivers face when patients are prescribed oral anticancer agents (OAA). Strategies for clinicians to support these family caregivers will be discussed
Patients with advanced-stage cancer: Caregivers perspective on patient symptoms, treatment sessions, and coping
Attendees will learn about perspectives on patient symptoms, difficulties during treatment, and coping needs in caregivers of advanced stage cancer survivors (ASCS). Strategies for interventions to support these caregivers will be discussed
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