158,101 research outputs found

    Phase Diagram for Nflation

    Get PDF
    Recently, it was showed that there is a large N phase transition in Nflation, in which when the number of fields is large enough, the slow roll inflation phase will disappear. In this brief report, we illustrate the phase diagram for Nflation, and discuss the entropy bound and some relevant results. It is found that near the critical point the number of fields saturates dS entropy.Comment: 4 pages, 1 eps figure, contents extended, published versio

    Phase Diagram of Li_xFePO_4

    Get PDF
    The phase diagram for LixFePO4 has been determined for different lithium concentrations and temperatures. The two low-temperature phases, heterosite and triphylite, have previously been shown to transform to a disordered solid solution at elevated temperatures. This disordered phase allows for a continuous transition between the heterosite and triphylite phases and is stable at relatively low temperatures. At intermediate temperatures the proposed phase diagram resembles a eutectoid system, with eutectoid point at around x=0.6 and 200°C. Kinetics of mixing and unmixing transformations are reported, including the hysteresis between heating and cooling. The enthalpy of this transition is at least 700 J/mol

    The Granular Phase Diagram

    Full text link
    The kinetic energy distribution function satisfying the Boltzmann equation is studied analytically and numerically for a system of inelastic hard spheres in the case of binary collisions. Analytically, this function is shown to have a similarity form in the simple cases of uniform or steady-state flows. This determines the region of validity of hydrodynamic description. The latter is used to construct the phase diagram of granular systems, and discriminate between clustering instability and inelastic collapse. The molecular dynamics results support analytical results, but also exhibit a novel fluctuational breakdown of mean-field descriptions.Comment: 15 pages, 4 figure

    Global quantum Hall phase diagram from visibility diagrams

    Full text link
    We propose a construction of a global phase diagram for the quantum Hall effect. This global phase diagram is based on our previous constructions of visibility diagrams in the context of the Quantum Hall Effect. The topology of the phase diagram we obtain is in good agreement with experimental observations (when the spin effect can be neglected). This phase diagram does not show floating.Comment: LaTeX2e, 9 pages, 5 eps figure

    New Phase Diagram for Black Holes and Strings on Cylinders

    Full text link
    We introduce a novel type of phase diagram for black holes and black strings on cylinders. The phase diagram involves a new asymptotic quantity called the relative binding energy. We plot the uniform string and the non-uniform string solutions in this new phase diagram using data of Wiseman. Intersection rules for branches of solutions in the phase diagram are deduced from a new Smarr formula that we derive.Comment: 19 pages, 6 figures, v2: typos corrected, v3: refs. added, comment on bounds on the relative binding energy n added in end of section

    Phase diagram of magnetic polymers

    Full text link
    We consider polymers made of magnetic monomers (Ising or Heisenberg-like) in a good solvent. These polymers are modeled as self-avoiding walks on a cubic lattice, and the ferromagnetic interaction between the spins carried by the monomers is short-ranged in space. At low temperature, these polymers undergo a magnetic induced first order collapse transition, that we study at the mean field level. Contrasting with an ordinary Θ\Theta point, there is a strong jump in the polymer density, as well as in its magnetization. In the presence of a magnetic field, the collapse temperature increases, while the discontinuities decrease. Beyond a multicritical point, the transition becomes second order and Θ\Theta-like. Monte Carlo simulations for the Ising case are in qualitative agreement with these results.Comment: 29 pages, 15 eps figures (one color figure). Submitted for publication to Eur.Phys.J.

    Ferromagnetism in QCD phase diagram

    Full text link
    A possibility and properties of spontaneous magnetization in quark matter are investigated. Magnetic susceptibility is evaluated within Fermi liquid theory, taking into account of the screening effect of gluons. Spin wave in the polarized quark matter, as the Nambu-Goldstone mode, is formulated by way of the coherent-state path integral.Comment: 9pages,1 figure, Proc. of EXOCT 200

    Mapping the QCD Phase Diagram

    Get PDF
    I review recent theoretical developments which show how a key qualitative feature of the QCD phase diagram, namely a critical point which in a sense defines the landscape which heavy ion collision experiments are seeking to map, can be discovered. The map of the phase diagram which I sketch is based on reasonable inference from universality, lattice gauge theory and models; the discovery of the critical point would provide an experimental foundation for the central qualitative feature of the landscape. I also review recent progress in our understanding of cold, dense quark matter, as may occur in the cores of neutron stars. In this regime, quarks form Cooper pairs. The formation of such superconducting phases requires only weak attractive interactions, as provided by one-gluon exchange at asymptotically high density; these phases may nevertheless break chiral symmetry (by locking flavor symmetries to color symmetry) and may have excitations which are indistinguishable from those in a confined phase. Mapping this part of the phase diagram will require a better understanding of how the presence of color superconductivity and color-flavor locking affects neutron star phenomenology.Comment: Contribution to proceedings of Quark Matter '99, Torino, Italy. 12 pages. 4 figure
    corecore