10,559 research outputs found
Logarithmic Corrections for Spin Glasses, Percolation and Lee-Yang Singularities in Six Dimensions
We study analytically the logarithmic corrections to the critical exponents
of the critical behavior of correlation length, susceptibility and specific
heat for the temperature and the finite-size scaling behavior, for a generic
theory at its upper critical dimension (six). We have also computed
the leading correction to scaling as a function of the lattice size. We
distinguish the obtained formulas to the following special cases: percolation,
Lee-Yang (LY) singularities and -component spin glasses. We have compared
our results for the Ising spin glass case with numerical simulations finding a
very good agreement. Finally, and using the results obtained for the Lee-Yang
singularities in six dimensions, we have computed the logarithmic corrections
to the singular part of the free energy for lattice animals in eight
dimensions.Comment: 18 pages. We have extended the computation to lattice animals in
eight dimensions. To be published in Journal of Physics
Velocity-force characteristics of a driven interface in a disordered medium
Using a dynamic functional renormalization group treatment of driven elastic
interfaces in a disordered medium, we investigate several aspects of the
creep-type motion induced by external forces below the depinning threshold
: i) We show that in the experimentally important regime of forces
slightly below the velocity obeys an Arrhenius-type law
with an effective energy barrier
vanishing linearly when f approaches the threshold . ii) Thermal
fluctuations soften the pinning landscape at high temperatures. Determining the
corresponding velocity-force characteristics at low driving forces for internal
dimensions d=1,2 (strings and interfaces) we find a particular non-Arrhenius
type creep involving the reduced threshold
force alone. For d=3 we obtain a similar v-f characteristic which is,
however, non-universal and depends explicitly on the microscopic cutoff.Comment: 9 pages, RevTeX, 3 postscript figure
"Glassy Dynamics" in Ising Spin Glasses -- Experiment and Simulation
The field-cooled magnetization (FCM) processes of Ising spin glasses under
relatively small fields are investigated by experiment on
Fe_{0.55}Mn_{0.45}TiO_3 and by numerical simulation on the three-dimensional
Edwards-Anderson model. Both results are explained in a unified manner by means
of the droplet picture. In particular, the cusp-like behavior of the FCM is
interpreted as evidence, not for an equilibrium phase transition under a finite
magnetic field, but for a dynamical (`blocking') transition frequently observed
in glassy systems.Comment: 4 pages, 7 figure
European Society for Sexual Medicine position statement 'Assessment and hormonal management in adolescent and adult trans people, with attention for sexual function and satisfaction'
Background: There is a general lack of recommendations for and basic information tailored at sexologists and other health-care professionals for when they encounter trans people in their practice.
Aim: We present to clinicians an up-to-date overview of clinical consensus statements on trans health care with attention for sexual function and satisfaction.
Methods: The task force consisted of 7 clinicians experienced in trans health care, selected among European Society for Sexual Medicine (ESSM) scientific committee. The consensus was guided by clinical experience and a review of the available literature and by interactive discussions on trans health, with attention for sexual function and satisfaction where available.
Outcomes: The foci of the study are assessment and hormonal aspects of trans health care.
Results: As the available literature for direct recommendations was limited, most of the literature was used as background or indirect evidence. Clinical consensus statements were developed based on clinical experiences and the available literature. With the multiple barriers to care that many trans people experience, basic care principles still need to be stressed. We recommend that health-care professionals (HCPs) working with trans people recognize the diversity of genders, including male, female, and nonbinary individuals. In addition, HCPs assessing gender diverse children and adolescents should take a developmental approach that acknowledges the difference between prepubescent gender diverse children and pubescent gender diverse adolescents and trans adults. Furthermore, trans people seeking gender-affirming medical interventions should be assessed by HCPs with expertise in trans health care and gender-affirming psychological practice. If masculinization is desired, testosterone therapy with monitoring of serum sex steroid levels and signs of virilization is recommended. Similarly, if feminization is desired, we recommend estrogens and/or antiandrogen therapy with monitoring of serum sex steroid levels and signs of feminization. HCPs should be aware of the influence of hormonal therapy on sexual functioning and satisfaction. We recommend HCPs be aware of potential sexual problems during all surgical phases of treatment.
Clinical Implications: This is an up-to-date ESSM position statement.
Strengths & Limitations: These statements are based on the data that are currently available; however, it is vital to recognize that this is a rapidly changing field and that the literature, particularly in the field of sexual functioning and satisfaction, is limited.
Conclusion: This ESSM position statement provides relevant information and references to existing clinical guidelines with the aim of informing relevant HCPs on best practices when working with transgender people
Star Formation History at the Centers of Lenticular Galaxies with Bars and Purely Exponential Outer Disks from SAURON Data
We have investigated the stellar population properties in the central regions
of a sample of lenticular galaxies with bars and single-exponential outer
stellar disks using the data from the SAURON integral-field spectrograph
retrieved from the open Isaac Newton Group Archive. We have detected chemically
decoupled compact stellar nuclei with a metallicity twice that of the stellar
population in the bulges in seven of the eight galaxies. A starburst is
currently going on at the center of the eighth galaxy and we have failed to
determine the stellar population properties from its spectrum. The mean stellar
ages in the chemically decoupled nuclei found range from 1 to 11 Gyr. The
scenarios for the origin of both decoupled nuclei and lenticular galaxies as a
whole are discussed.Comment: 10 pages, 4 figures, a slightly edited version of the paper published
by Astronomy Letters, v. 37, no.1, 201
Field-Shift Aging Protocol on the 3D Ising Spin-Glass Model: Dynamical Crossover between the Spin-Glass and Paramagnetic States
Spin-glass (SG) states of the 3-dimensional Ising Edwards-Anderson model
under a static magnetic field are examined by means of the standard Monte
Carlo simulation on the field-shift aging protocol at temperature . For each
process with (T; \tw, h), \tw being the waiting time before the field is
switched on, we extract the dynamical crossover time, \tcr(T; \tw, h). We
have found a nice scaling relation between the two characteristic length scales
which are properly determined from \tcr and \tw and then are normalized by
the static field crossover length introduced in the SG droplet theory. This
scaling behavior implies the instability of the SG phase in the equilibrium
limit even under an infinitesimal . In comparison with this numerical result
the field effect on real spin glasses is also discussed.Comment: 4 pages, 5 figures, jpsj2, Changed conten
Identity of the universal repulsive-core singularity with Yang-Lee edge criticality
Lattice and continuum fluid models with repulsive-core interactions typically
display a dominant, critical-type singularity on the real, negative activity
axis. Lai and Fisher recently suggested, mainly on numerical grounds, that this
repulsive-core singularity is universal and in the same class as the Yang-Lee
edge singularities, which arise above criticality at complex activities with
positive real part. A general analytic demonstration of this identification is
presented here using a field-theory approach with separate representation of
the repulsive and attractive parts of the pair interactions.Comment: 6 pages, 3 figure
The depinning transition of a driven interface in the random-field Ising model around the upper critical dimension
We investigate the depinning transition for driven interfaces in the
random-field Ising model for various dimensions. We consider the order
parameter as a function of the control parameter (driving field) and examine
the effect of thermal fluctuations. Although thermal fluctuations drive the
system away from criticality the order parameter obeys a certain scaling law
for sufficiently low temperatures and the corresponding exponents are
determined. Our results suggest that the so-called upper critical dimension of
the depinning transition is five and that the systems belongs to the
universality class of the quenched Edward-Wilkinson equation.Comment: accepted for publication in Phys. Rev.
Ising Spin Glasses in a Magnetic Field
Ground states of the three dimensional Edwards-Anderson spin glass are
computed in the presence of an external magnetic field. Our algorithm is
sufficiently powerful for us to treat systems with up to 600 spins. We perform
a statistical analysis of how the ground state changes as the field is
increased, and reach the conclusion that the spin glass phase at zero
temperature does not survive in the presence of any finite field. This is in
agreement with the droplet model or scaling predictions, but in sharp
disagreement with the mean field picture. For comparison, we also investigate a
dilute mean field spin glass model where an Almeida-Thouless line is present.Comment: 4 pages, 4 figures, Revte
Finite Size Analysis of Luttinger Liquids with a source of 2k_f Scattering
Numerical analysis of the spectrum of large finite size Luttinger liquids
(g<1) in the presence of a single source of 2k_f scattering has been made
possible thanks to an effective integration of high degrees of freedom.
Presence of irrelevant operators and their manifestation in transport are
issues treated independently. We confirm the existence of two irrelevant
operators: particle hopping and charge oscillations, with regions of dominance
separated by g=1/2. Temperature dependence of conductance is shown to be
dominated by hopping alone. Frequency dependence is affected by both irrelevant
operators.Comment: 4 pages, LaTex (RevTex), 3 PostScript figures appende
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