The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Bivudutta Mishra - One of the best experts on this subject based on the ideXlab platform.
-
Scale Invariant Theory of Gravitation in Einstein-Rosen Space-Time
2010Co-Authors: Bivudutta Mishra, Parbati Sahoo, Addepalli RamuAbstract:In this paper, we have studied the perfect fluid distribution in the scale invariant theory of gravitation, when the space-time is described by Einstein-Rosen metric with a time dependent Gauge Function. The cosmological equations for this space-time with Gauge Functions are solved and some physical properties of the model are studied.
-
Non-Static Plane Symmetric Zeldovich Fluid Model In Scale Invariant Theory
Chinese Physics Letters, 2004Co-Authors: Bivudutta MishraAbstract:We study the perfect fluid distribution in scale invariant theory of gravitation, when the spacetime is described by non-static plane symmetric metric with a time-dependent Gauge Function. The Zeldovich model of the universe is constructed and some physical properties of the model are discussed.
-
Bianchi type I cosmological perfect fluid model in scale invariant theory
Astrophysics and Space Science, 2003Co-Authors: Bivudutta MishraAbstract:The intention of this paper is to study the perfect fluid distribution in scale invariant theory of gravity when the space-time is described by Bianchi type I metric with a time dependent Gauge Function. The cosmological equations for this space-time with Gauge Function are solved and some physical properties of the model are discussed.
-
Non-static plane symmetric cosmological model in Wesson’s theory
Pramana, 2003Co-Authors: Bivudutta MishraAbstract:The problem of non-static plane symmetric perfect fluid distribution in Wesson’s [1] scale invariant theory of gravitation with a time-dependent Gauge Function is investigated. The false vacuum model of the universe is constructed and some physical properties of the model are discussed.
-
Bianchi Type V False Vacuum Cosmological Model in Scale-Invariant Theory
Czechoslovak Journal of Physics, 2003Co-Authors: Bivudutta MishraAbstract:Intention of this paper is to study the perfect fluid distribution in scale-invariant theory of gravity when the space-time is described by Bianchi type V metric with a time-dependent Gauge Function (Dirac Gauge). In this theory the false vacuum model of the universe is constructed and physical behaviors of the model is discussed.
Pei-hung Yuan - One of the best experts on this subject based on the ideXlab platform.
-
A Refined Holographic QCD Model and QCD Phase Structure
Journal of High Energy Physics, 2014Co-Authors: Yi Yang, Pei-hung YuanAbstract:We consider the Einstein-Maxwell-dilaton system with an arbitrary kinetic Gauge Function and a dilaton potential. A family of analytic solutions is obtained by the potential reconstruction method. We then study its holographic dual QCD model. After fixing the kinetic Gauge Function by requesting the linear Regge spectrum of mesons, we calculate the free energy to obtain the phase diagram of the holographic QCD model
-
Phase Structure in a Dynamical Soft-Wall Holographic QCD Model
Journal of High Energy Physics, 2013Co-Authors: Yi Yang, Pei-hung YuanAbstract:We consider the Einstein-Maxwell-dilaton system with an arbitrary kinetic Gauge Function and a dilaton potential. A family of analytic solutions is obtained by the potential reconstruction method. We then study its holographic dual QCD model. The kinetic Gauge Function can be fixed by requesting the linear Regge spectrum of mesons. We calculate the free energy to obtain the phase diagram of the holographic QCD model and interpret our result as the heavy quarks system by comparing the recent lattice QCD simulation. We finally obtain the equations of state in our model.
Thomas Duquesne - One of the best experts on this subject based on the ideXlab platform.
-
Exact packing measure of the range of ψ-Super Brownian motions
Probability Theory and Related Fields, 2015Co-Authors: Xan Duhalde, Thomas DuquesneAbstract:We consider super processes whose spatial motion is the d-dimensional Brownian motion and whose branching mechanism ψ is critical or subcritical; such processes are called ψ-super Brownian motions. If d>2γγ/(γγ−1), where γγ∈(1,2] is the lower index of ψ at ∞, then the total range of the ψ-super Brownian motion has an exact packing measure whose Gauge Function is g(r)=(loglog1/r)/φ−1((1/rloglog1/r)2), where φ=ψ′∘ψ−1. More precisely, we show that the occupation measure of the ψ-super Brownian motion is the g-packing measure restricted to its total range, up to a deterministic multiplicative constant only depending on d and ψ. This generalizes the main result of Duquesne (Ann Probab 37(6):2431–2458, 2009) that treats the quadratic branching case. For a wide class of ψ, the constant 2γγ/(γγ−1) is shown to be equal to the packing dimension of the total range
-
Exact packing measure of the range of $\psi$-Super Brownian motions.
2014Co-Authors: Thomas Duquesne, Xan DuhaldeAbstract:We consider super processes whose spatial motion is the $d$-dimensional Brownian motion and whose branching mechanism $\psi$ is critical or subcritical; such processes are called $\psi$-super Brownian motions. If $d\!>\!2\bgamma/(\bgamma\!-\!1)$, where $\bgamma\!\in\!(1,2]$ is the lower index of $\psi$ at $\infty$, then the total range of the $\psi$-super Brownian motion has an exact packing measure whose Gauge Function is $g(r)\! =\! (\log\log1/r) / \varphi^{-1} ( (1/r\log\log 1/r)^{2})$, where $\varphi\! =\! \psi^\prime\! \circ \! \psi^{\!-1}$. More precisely, we show that the occupation measure of the $\psi$-super Brownian motion is the $g$-packing measure restricted to its total range, up to a deterministic multiplicative constant only depending on $d$ and $\psi$. This generalizes the main result of \cite{Duq09} that treats the quadratic branching case. For a wide class of $\psi$, the constant $2\bgamma/(\bgamma\!-\!1)$ is shown to be equal to the packing dimension of the total range.
-
Packing and Hausdorff measures of stable trees.
2010Co-Authors: Thomas DuquesneAbstract:In this paper we discuss Hausdorff and packing measures of random continuous trees called stable trees. Stable trees form a specific class of Lévy trees (introduced by Le Gall and Le Jan in 1998) that contains Aldous's continuum random tree (1991) which corresponds to the Brownian case. We provide results for the whole stable trees and for their level sets that are the sets of points situated at a given distance from the root. We first show that there is no exact packing measure for levels sets. We also prove that non-Brownian stable trees and their level sets have no exact Hausdorff measure with regularly varying Gauge Function, which continues previous results from a joint work with J-F Le Gall (2006).
-
The exact packing measure of Lévy trees
2010Co-Authors: Thomas DuquesneAbstract:We study fine properties of Lévy trees that are random compact metric spaces introduced by Le Gall and Le Jan in 1998 as the genealogy of continuous state branching processes. Lévy trees are the scaling limits of Galton-Watson trees and they generalize Aldous's continuum random tree which corresponds to the Brownian case. In this paper we prove that Lévy trees have always an exact packing measure: We explicitely compute the packing Gauge Function and we prove that the corresponding packing measure coincides with the mass measure up to a multiplicative constant.
-
An Elementary Proof of Hawkes's Conjecture on Galton-Watson Trees
2008Co-Authors: Thomas DuquesneAbstract:In 1981, J. Hawkes conjectured the exact form of the Hausdorff Gauge Function for the boundary of supercritical Galton-Watson trees under a certain assumption on the tail at the infinity of the total mass of the branching measure. Hawkes's conjecture has been proved by T. Watanabe in 2007 as well as other other precise results on fractal properties of the boundary of Galton-Watson trees. The goal of this paper is to provide an elementary proof of Hawkes's conjecture under a less restrictive assumption than in T. Watanabe's paper, by use of size-biased Galton-Watson trees introduced by Lyons, Pemantle and Peres in 1995.
Yi Yang - One of the best experts on this subject based on the ideXlab platform.
-
A Refined Holographic QCD Model and QCD Phase Structure
Journal of High Energy Physics, 2014Co-Authors: Yi Yang, Pei-hung YuanAbstract:We consider the Einstein-Maxwell-dilaton system with an arbitrary kinetic Gauge Function and a dilaton potential. A family of analytic solutions is obtained by the potential reconstruction method. We then study its holographic dual QCD model. After fixing the kinetic Gauge Function by requesting the linear Regge spectrum of mesons, we calculate the free energy to obtain the phase diagram of the holographic QCD model
-
Phase Structure in a Dynamical Soft-Wall Holographic QCD Model
Journal of High Energy Physics, 2013Co-Authors: Yi Yang, Pei-hung YuanAbstract:We consider the Einstein-Maxwell-dilaton system with an arbitrary kinetic Gauge Function and a dilaton potential. A family of analytic solutions is obtained by the potential reconstruction method. We then study its holographic dual QCD model. The kinetic Gauge Function can be fixed by requesting the linear Regge spectrum of mesons. We calculate the free energy to obtain the phase diagram of the holographic QCD model and interpret our result as the heavy quarks system by comparing the recent lattice QCD simulation. We finally obtain the equations of state in our model.
Zhiying Wen - One of the best experts on this subject based on the ideXlab platform.
-
Gauges for the self‐similar sets
Mathematische Nachrichten, 2008Co-Authors: Sheng You Wen, Zhi‐xiong Wen, Zhiying WenAbstract:For a self-similar set E with the open set condition we completely determine the class of its Hausdorff Gauges and the class of its prepacking Gauges. Moreover, its Hausdorff measures and its packing premeasures with respect to the corresponding Gauges are estimated. Without the open set condition we prove that a doubling Gauge Function is a packing Gauge of E if and only if it is a prepacking Gauge of E. Also, we give some extensions and applications of these results. Here a Gauge Function is called a Hausdorff, a prepacking, and a packing Gauge of a set, if with respect to the Function the set has positive and finite Hausdorff measure, packing premeasure, and packing measure, respectively. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
-
Relations among Gauge Functions, metrics and Hausdorff measures
Progress in Natural Science, 2003Co-Authors: Sheng You Wen, Zhiying WenAbstract:Abstract In this paper we discuss the relations among the doubling condition, equivalence of the Hausdorff measures and equivalence of metrics. We will show that ℋ ρ,g1 and ℋ ρ,g2 are equivalent for any compact metric space (X, ρ) if and only if g 1 and g 2 are equivalent GaugeFunctions. Then, we prove that for given c e (0, ∞) ∖ {1}, ℋ ρ g and ℋ cρ g are equivalent for any compact metric space (X, ρ) if and only if the Gauge Function g satisfies the doubling condition, where ℋ ρ, g is the Hausdorff measure with respect to the metric ρ and Gauge Function g.