Description of Friedmann Observables in Quantum Universe

The solution of the problem of describing the Friedmann observables (the Hubble law, the red shift, etc.) in quantum cosmology is proposed on the basis of the method of gaugeless Hamiltonian reduction in which the gravitational part of the energy constraint is considered as a new momentum. We show that the conjugate variable corresponding to the new momentum plays a role of the invariant time parameter of evolution of dynamical variables in the sector of the Dirac observables of the general Hamiltonian approach. Relations between these Dirac observables and the Friedmann observables of the expanding Universe are established for the standard Friedmann cosmological model with dust and radiation. The presented reduction removes an infinite factor from the functional integral, provides the normalizability of the wave function of the Universe and distinguishes the conformal frame of reference where the Hubble law is caused by the alteration of the conformal dust mass.Comment: 10 pages, LaTe

Bianchi type I cyclic cosmology from Lie-algebraically deformed phase space

We study the effects of noncommutativity, in the form of a Lie-algebraically deformed Poisson commutation relations, on the evolution of a Bianchi type I cosmological model with a positive cosmological constant. The phase space variables turn out to correspond to the scale factors of this model in $x$, $y$ and $z$ directions. According to the conditions that the structure constants (deformation parameters) should satisfy, we argue that there are two types of noncommutative phase space with Lie-algebraic structure. The exact classical solutions in commutative and type I noncommutative cases are presented. In the framework of this type of deformed phase space, we investigate the possibility of building a Bianchi I model with cyclic scale factors in which the size of the universe in each direction experiences an endless sequence of contractions and re-expansions. We also obtain some approximate solutions for the type II noncommutative structure by numerical methods and show that the cyclic behavior is repeated as well. These results are compared with the standard commutative case, and similarities and differences of these solutions are discussed.Comment: 13 pages, to appear in PRD, typos corrected, Refs. adde

The Violin Students of Shakeh Ghoukasian

Program listing performers and works performe

Gravitational Waves versus X and Gamma Ray Emission in a Short Gamma-Ray Burst

The recent progress in the understanding the physical nature of neutron star equilibrium configurations and the first observational evidence of a genuinely short gamma-ray burst, GRB 090227B, allows to give an estimate of the gravitational waves versus the X and Gamma-ray emission in a short gamma-ray burst.Comment: Version to appear in Ap

Exact Hypersurface-Homogeneous Solutions in Cosmology and Astrophysics

A framework is introduced which explains the existence and similarities of most exact solutions of the Einstein equations with a wide range of sources for the class of hypersurface-homogeneous spacetimes which admit a Hamiltonian formulation. This class includes the spatially homogeneous cosmological models and the astrophysically interesting static spherically symmetric models as well as the stationary cylindrically symmetric models. The framework involves methods for finding and exploiting hidden symmetries and invariant submanifolds of the Hamiltonian formulation of the field equations. It unifies, simplifies and extends most known work on hypersurface-homogeneous exact solutions. It is shown that the same framework is also relevant to gravitational theories with a similar structure, like Brans-Dicke or higher-dimensional theories.Comment: 41 pages, REVTEX/LaTeX 2.09 file (don't use LaTeX2e !!!) Accepted for publication in Phys. Rev.

Effect of rehabilitation worker input on visual function outcomes in individuals with low vision: study protocol for a randomised controlled trial

BACKGROUND: Visual Rehabilitation Officers help people with a visual impairment maintain their independence. This intervention adopts a flexible, goal-centred approach, which may include training in mobility, use of optical and non-optical aids, and performance of activities of daily living. Although Visual Rehabilitation Officers are an integral part of the low vision service in the United Kingdom, evidence that they are effective is lacking. The purpose of this exploratory trial is to estimate the impact of a Visual Rehabilitation Officer on self-reported visual function, psychosocial and quality-of-life outcomes in individuals with low vision. METHODS/DESIGN: In this exploratory, assessor-masked, parallel group, randomised controlled trial, participants will be allocated either to receive home visits from a Visual Rehabilitation Officer (n = 30) or to a waiting list control group (n = 30) in a 1:1 ratio. Adult volunteers with a visual impairment, who have been identified as needing rehabilitation officer input by a social worker, will take part. Those with an urgent need for a Visual Rehabilitation Officer or who have a cognitive impairment will be excluded. The primary outcome measure will be self-reported visual function (48-item Veterans Affairs Low Vision Visual Functioning Questionnaire). Secondary outcome measures will include psychological and quality-of-life metrics: the Patient Health Questionnaire (PHQ-9), the Warwick-Edinburgh Mental Well-being Scale (WEMWBS), the Adjustment to Age-related Visual Loss Scale (AVL-12), the Standardised Health-related Quality of Life Questionnaire (EQ-5D) and the UCLA Loneliness Scale. The interviewer collecting the outcomes will be masked to the group allocations. The analysis will be undertaken on a complete case and intention-to-treat basis. Analysis of covariance (ANCOVA) will be applied to follow-up questionnaire scores, with the baseline score as a covariate. DISCUSSION: This trial is expected to provide robust effect size estimates of the intervention effect. The data will be used to design a large-scale randomised controlled trial to evaluate fully the Visual Rehabilitation Officer intervention. A rigorous evaluation of Rehabilitation Officer input is vital to direct a future low vision rehabilitation strategy and to help direct government resources. TRIAL REGISTRATION: The trial was registered with ( ISRCTN44807874 ) on 9 March 2015

Sexual attraction, sexual identity, and psychosocial well-being in a national sample of young women during emerging adulthood.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106627/1/Sexual attraction, sexual identity, and psychosocial well-being in a national sample of young women during emerging adulthood.pd

Early formation of galaxies initiated by clusters of primordial black holes

Model of supermassive black holes formation inside the clusters of primordial black holes is developed. Namely, it is supposed, that some mass fraction of the universe ~10^-3 is composed of the compact clusters of primordial (relic) black holes, produced during phase transitions in the early universe. These clusters are the centers of dark matter condensation. We model the formation of protogalaxies with masses about 2*10^8M_sun at the redshift z=15. These induced protogalaxies contain central black holes with mass ~10^5M_sun and look like dwarf spheroidal galaxies with central density spike. The subsequent merging of induced protogalaxies and ordinary dark matter haloes corresponds to the standard hierarchical clustering scenario of large-scale structure formation. The coalescence of primordial black holes results in formation of supermassive black holes in the galactic centers. As a result, the observed correlation between the masses of central black holes and velocity dispersion in the galactic bulges is reproduced.Comment: 13 pages, 5 figures, accepted for publication in Astron. Rep. (Astronomicheskii Zhurnal

Do Birds of a Feather Play Sports Together? Moderators of the Similarity-Attraction Relationship in the Context of Sports and Physical Activities

Ph.D. University of Hawaii at Manoa 2016.Includes bibliographical references.Psychological theories of similarity and attraction predict that common interests and participation in particular sports and physical activities (SPA) will lead to greater attraction. However, both social structural and evolutionary sexual strategies theories predict that the sexes will engage in different SPAs. Furthermore, SPAs are theorized to function as cultural courtship rituals by which people make inferences regarding desirable mate characteristics. The current study sought to examine whether relationship context, participants’ sex, and their sex-role attitudes moderated the similarity-attraction relationship and whether perceived characteristics associated with particular SPA participation influence interpersonal attraction. Using an online questionnaire, heterosexual participants (N = 336 females, 174 males) were provided a list of 29 SPAs and rated each on levels of personal interest and experience, perceived characteristics associated with people who engage in each SPA, and interpersonal attraction towards people who engage in those SPAs in four relationship contexts (same- and other-sex friendships, short-term sexual relationships, and long-term romances). Similarity in SPAs was found to be positively associated with attraction, significantly moderated by the interaction with participant’s sex and relationship context, and significantly more influential across relationship contexts for participants with traditional sex-role attitudes. Perceptions of gender-role alignment with SPA engagement predicted interpersonal attraction. Although females strongly associated male athletes as being athletic and physically strong, these characteristic perceptions were not found to align with their ratings of interpersonal attraction. Males were significantly more influenced by perceptions of kindness in romantic contexts than females. In opposite-sex relationship contexts, both sexes prioritized perceived physical attractiveness followed by social popularity

Sex differences in mate preferences for athletic prowess

Thesis (M.A.)--University of Hawaii at Manoa, 2008.Includes bibliographical references (leaves 58-61).x, 61 leaves, bound 29 cmWhile athletic ability and success in sports is a valued trait in society, little is known about how athletic ability affects mate choice decisions. Research on mate preferences for athletic prowess is limited and conflicting regarding possible sex differences. The present study utilized a mate-screening paradigm to test for possible sex differences in mate-choice decisions regarding a potential mate's athletic ability by substituting the cue of "athletic" for sex-specific necessity traits ("social level" for females and "physical attractiveness" for men). When "physical attractiveness" was not an available cue, males inquired about a potential mate's athletic ability significantly more often than females. However level of athleticism did not influence males mate selection choices. Contrary to expectations, females did not focus on athleticism when the cue for social level was unavailable