226 research outputs found
âShowing people part of your lifeâ: service-user experiences of taking and sharing photographs in a DBT-informed emotional coping skills group
The added value of using photographs to explore experiences has been embraced in research methods such as photo-elicitation and Photovoice. Despite evidence that photographs aid communication and understanding, there is little research investigating photograph use within cognitive behavioural therapy. This project explores participant experiences of taking and sharing photographs within a dialectical behaviour therapy (DBT)-informed emotional coping skills group intervention. Five service users were recruited from groups that had implemented the taking and sharing of photographs as a feature of homework tasks and feedback. Semi-structured interviews were conducted, using the photographs taken for the group as prompts, and interpretive phenomenological analysis was used to develop themes. Group evaluation data were used to support the analysis. Participants were positive about the impact of the photographs, despite initially experiencing anxieties regarding sharing them. The task supported them to express themselves in ways that added value to verbal feedback, which had benefits for group relationships and for the therapeutic tasks such as mindful observing. Further research is indicated, given the small sample and participants all being white, working-age females. However, the findings suggest that using photographs as homework tasks could support communication and the exploration of experiences that may be difficult to express using words
A General Relativistic Rotating Evolutionary Universe - Part II
As a sequel to (Berman, 2008a), we show that the rotation of the Universe can
be dealt by generalised Gaussian metrics, defined in this paper.
Robertson-Walker's metric has been employed with proper-time, in its standard
applications; the generalised Gaussian metric imply in the use of a
non-constant temporal metric coefficient modifying Robertson-Walker's standard
form. Experimental predictions are madeComment: 7 pages including front cover. Publishe
Can induced gravity isotropize Bianchi I, V, or IX Universes?
We analyze if Bianchi I, V, and IX models in the Induced Gravity (IG) theory
can evolve to a Friedmann--Roberson--Walker (FRW) expansion due to the
non--minimal coupling of gravity and the scalar field. The analytical results
that we found for the Brans-Dicke (BD) theory are now applied to the IG theory
which has ( being the square ratio of the Higgs to
Planck mass) in a cosmological era in which the IG--potential is not
significant. We find that the isotropization mechanism crucially depends on the
value of . Its smallness also permits inflationary solutions. For the
Bianch V model inflation due to the Higgs potential takes place afterwads, and
subsequently the spontaneous symmetry breaking (SSB) ends with an effective FRW
evolution. The ordinary tests of successful cosmology are well satisfied.Comment: 24 pages, 5 figures, to be published in Phys. Rev. D1
Collisional equilibrium, particle production and the inflationary universe
Particle production processes in the expanding universe are described within
a simple kinetic model. The equilibrium conditions for a Maxwell-Boltzmann gas
with variable particle number are investigated. We find that radiation and
nonrelativistic matter may be in equilibrium at the same temperature provided
the matter particles are created at a rate that is half the expansion rate.
Using the fact that the creation of particles is dynamically equivalent to a
nonvanishing bulk pressure we calculate the backreaction of this process on the
cosmological dynamics. It turns out that the `adiabatic' creation of massive
particles with an equilibrium distribution for the latter necessarily implies
power-law inflation. Exponential inflation in this context is shown to become
inconsistent with the second law of thermodynamics after a time interval of the
order of the Hubble time.Comment: 19 pages, latex, no figures, to appear in Phys.Rev.
Illusions of general relativity in Brans-Dicke gravity
Contrary to common belief, the standard tenet of Brans-Dicke theory reducing
to general relativity when omega tends to infinity is false if the trace of the
matter energy-momentum tensor vanishes. The issue is clarified in a new
approach using conformal transformations. The otherwise unaccountable limiting
behavior of Brans-Dicke gravity is easily understood in terms of the conformal
invariance of the theory when the sources of gravity have radiation-like
properties. The rigorous computation of the asymptotic behavior of the
Brans-Dicke scalar field is straightforward in this new approach.Comment: 16 pages, LaTeX, to appear in Physical Review
Conformal aspects of Palatini approach in Extended Theories of Gravity
The debate on the physical relevance of conformal transformations can be
faced by taking the Palatini approach into account to gravitational theories.
We show that conformal transformations are not only a mathematical tool to
disentangle gravitational and matter degrees of freedom (passing from the
Jordan frame to the Einstein frame) but they acquire a physical meaning
considering the bi-metric structure of Palatini approach which allows to
distinguish between spacetime structure and geodesic structure. Examples of
higher-order and non-minimally coupled theories are worked out and relevant
cosmological solutions in Einstein frame and Jordan frames are discussed
showing that also the interpretation of cosmological observations can
drastically change depending on the adopted frame
Validity of Generalized Second Law of Thermodynamics in the Logamediate and Intermediate scenarios of the Universe
In this work, we have investigated the validity of the generalized second law
of thermodynamics in logamediate and intermediate scenarios of the universe
bounded by the Hubble, apparent, particle and event horizons using and without
using first law of thermodynamics. We have observed that the GSL is valid for
Hubble, apparent, particle and event horizons of the universe in the
logamediate scenario of the universe using first law and without using first
law. Similarly the GSL is valid for all horizons in the intermediate scenario
of the universe using first law. Also in the intermediate scenario of the
universe, the GSL is valid for Hubble, apparent and particle horizons but it
breaks down whenever we consider the universe enveloped by the event horizon
Some remarks on the dynamical systems approach to fourth order gravity
Building on earlier work, we discuss a general framework for exploring the
cosmological dynamics of Higher Order Theories of Gravity. We show that once
the theory of gravity has been specified, the cosmological equations can be
written as a first-order autonomous system and we give several examples which
illustrate the utility of our method. We also discuss a number of results which
have appeared recently in the literature.Comment: 19 pages, LaTe
Disappearing Dark Matter in Brane World Cosmology: New Limits on Noncompact Extra Dimensions
We explore cosmological implications of dark matter as massive particles
trapped on a brane embedded in a Randall-Sundrum noncompact higher dimension
space. It is an unavoidable consequence of this cosmology that massive
particles are metastable and can disappear into the bulk dimension. Here, we
show that a massive dark matter particle (e.g. the lightest supersymmetric
particle) is likely to have the shortest lifetime for disappearing into the
bulk. We examine cosmological constraints on this new paradigm and show that
disappearing dark matter is consistent (at the 95% confidence level) with all
cosmological constraints, i.e. present observations of Type Ia supernovae at
the highest redshift, trends in the mass-to-light ratios of galaxy clusters
with redshift, the fraction of X-ray emitting gas in rich clusters, and the
spectrum of power fluctuations in the cosmic microwave background. A best concordance region is identified corresponding to a mean lifetime for
dark matter disappearance of Gyr. The implication
of these results for brane-world physics is discussed.Comment: 7 pages, 7 figures, new cosmological constraints added, accepted for
publication in PR
The Mathematical Universe
I explore physics implications of the External Reality Hypothesis (ERH) that
there exists an external physical reality completely independent of us humans.
I argue that with a sufficiently broad definition of mathematics, it implies
the Mathematical Universe Hypothesis (MUH) that our physical world is an
abstract mathematical structure. I discuss various implications of the ERH and
MUH, ranging from standard physics topics like symmetries, irreducible
representations, units, free parameters, randomness and initial conditions to
broader issues like consciousness, parallel universes and Godel incompleteness.
I hypothesize that only computable and decidable (in Godel's sense) structures
exist, which alleviates the cosmological measure problem and help explain why
our physical laws appear so simple. I also comment on the intimate relation
between mathematical structures, computations, simulations and physical
systems.Comment: Replaced to match accepted Found. Phys. version, 31 pages, 5 figs;
more details at http://space.mit.edu/home/tegmark/toe.htm
- âŠ