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We initiate a quantitative exploration of the entire landscape. Predictions thus far have focused on subsets of landscape vacua that share most properties with our own. Using the entropic principle (the assumption that entropy production…

High Energy Physics - Theory · Physics 2011-01-17 Raphael Bousso , Roni Harnik

We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-conventional kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Stefano Ansoldi , Eduardo I. Guendelman

As a solvable and broadly applicable model system, the totally asymmetric exclusion process enjoys iconic status in the theory of non-equilibrium phase transitions. Here, we focus on the time dependence of the total number of particles on a…

Statistical Mechanics · Physics 2009-11-13 D. A. Adams , R. K. P Zia , B. Schmittmann

We present a three-dimensional lattice-gas model with trivial thermodynamics, but nontrivial dynamics. The model is characterized by each particle having its own random energy landscape. The equilibrium dynamics of the model were…

Soft Condensed Matter · Physics 2012-03-27 Ulf R. Pedersen , Tina Hecksher , Jeppe C. Dyre , Thomas B. Schrøder

The decaying vacuum model (DV), treating dark energy as a varying vacuum, has been studied well recently. The vacuum energy decays linearly with the Hubble parameter in the late-times, $\rho_\Lambda(t) \propto H(t)$, and produces the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. L. Tong , H. Noh

The understanding of the fundamental properties of the climate system has long benefitted from the use of simple numerical models able to parsimoniously represent the essential ingredients of its processes. Here we introduce a new model for…

Chaotic Dynamics · Physics 2020-11-16 Gabriele Vissio , Valerio Lucarini

In this paper we focus on a type of inverse problem in which the data is expressed as an unknown function of the sought and unknown model function (or its discretised representation as a model parameter vector). In particular, we deal with…

Applications · Statistics 2019-08-19 Dalia Chakrabarty , Prasenjit Saha

An expanding universe is not expected to have a static vacuum energy density. The so-called cosmological constant $\Lambda$ should be an approximation, certainly a good one for a fraction of a Hubble time, but it is most likely a temporary…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Joan Sola

There is now strong evidence that the main contribution to the cosmic energy density is not due to matter, but to another component with negative pressure. Its nature is still unknown: it could be the vacuum energy, manifesting itself as a…

Astrophysics · Physics 2007-05-23 Alberto Cappi

We study the properties of the space-time that emerges dynamically from the matrix model for type IIB superstrings in ten dimensions. We calculate the free energy and the extent of space-time using the Gaussian expansion method up to the…

High Energy Physics - Theory · Physics 2015-05-30 Jun Nishimura , Toshiyuki Okubo , Fumihiko Sugino

In the framework of an effective field theory of general relativity a model of scalar and vector bosons interacting with the metric field is considered. It is shown in the framework of a two-loop order calculation that for the cosmological…

High Energy Physics - Theory · Physics 2019-08-30 J. Gegelia , Ulf-G. Meißner

The thermal history of a large class of running vacuum models in which the effective cosmological term is described by a truncated power series of the Hubble rate, whose dominant term is $\Lambda (H) \propto H^{n+2}$, is discussed in…

General Relativity and Quantum Cosmology · Physics 2016-04-29 J. A. S. Lima , Spyros Basilakos , Joan Solà

Accurately estimating latent velocity vector fields of atmospheric winds is crucial for understanding weather phenomena. Direct measurement of atmospheric winds is costly, especially in the upper atmosphere, so researchers attempt to…

Applications · Statistics 2025-06-12 Youssef Fahmy , Maria Laura Battagliola , Joseph Guinness

We explicitly construct the density matrix associated to the vacuum state of a large spherically symmetric causal diamond of area $A$ in four-dimensional asymptotically flat gravity. We achieve this using the soft effective action, which…

High Energy Physics - Theory · Physics 2026-05-28 Temple He , Prahar Mitra , Kathryn M. Zurek

We consider effective models of condensation where the condensation occurs as time t goes to infinity. We provide natural conditions under which the build-up of the condensate occurs on a spatial scale of 1/t and has the universal form of a…

Mathematical Physics · Physics 2018-07-04 Volker Betz , Steffen Dereich , Peter Mörters

The excluded volume effects of randomly branched polymers are investigated. To approach this problem we assume the Gaussian distribution of segments around the center of gravity. Once this approximation is introduced, we can make use of the…

Soft Condensed Matter · Physics 2017-09-27 Kazumi Suematsu

We speculate that the universe may be filled with a visco-elastic continuum which may be called aether. Thus, the Maxwell's equations in vacuum are derived by methods of continuum mechanics based on a continuum mechanical model of vacuum…

General Physics · Physics 2007-05-23 Xiao-Song Wang

With the decline of the Copenhagen interpretation of quantum mechanics and the recent experiments indicating that quantum mechanics does actually embody 'objective reality', one might ask if a 'mechanical', conceptual model for quantum…

Quantum Physics · Physics 2014-06-23 Carl Frederick

The problem of the vacuum energy decay is studied through the analysis of the vacuum survival amplitude ${\mathcal A}(z, z')$. Transition amplitudes are computed for finite time-span, $Z\equiv z^\prime-z$, and their {\em late time} behavior…

High Energy Physics - Theory · Physics 2011-11-10 Enrique Álvarez , Roberto Vidal

The massive scalar field with $\lambda\varphi^4$ interaction placed in $(3+1)$ dimensional box is considered. The sizes of the box are $V\times \beta$ $(V=L^3$ is the volume, $T=1/\beta$ is the temperature). The free energy is evaluated up…

High Energy Physics - Theory · Physics 2008-02-03 A. I. Bugrij , V. N. Shadura