Inflationary Cosmology Revisited: An Overview Of Contemporary Scientific Cosmology After The Inflationary Proposal
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Largest atom smasher sends beams in two directions. Big Bang - Cosmology - Physics - Astronomy Alternative - Anomalies and Alternative Science
Arxiv (Free subscription) | 40 minutes ago
If general relativity is an emergent phenomenon, there may be small violations of diffeomorphism invariance. We propose a phenomenology of perturbatively small violations of general relativity by the inclusion of terms which break general covariance. These can be tested by matching to the Parametrized Post Newtonian (PPN) formalism. The most sensitive tests involve pulsar timing and provide an extremely...
Arxiv (Free subscription) | 40 minutes ago
We present a separable version of Loop Quantum Gravity (LQG) based on an inductive system of cubic lattices. We construct semi-classical states for which the LQG operators -- the flux, the area and the volume operators -- have the right classical limits. Also, we present the Hamilton and diffeomorphism constraints as operator constraints and show that they have the right classical limit. Finally,...
Arxiv (Free subscription) | 40 minutes ago
An analytic understanding of the geodesic structure around non-Kerr spacetimes will result in a powerful tool that could make the mapping of spacetime around massive quiescent compact objects possible. To this end, I present an analytic closed form expression for the components of a the fourth order Killing tensor for Stationary Axisymmetric Vacuum (SAV) Spacetimes. It is as yet unclear what subset...
Arxiv (Free subscription) | 40 minutes ago
Effective potential for a class of static solutions of Kaluza-Klein equations with three- dimensional spherical symmetry is studied. Test particles motion is analyzed. In attempts to read the obtained results with the experimental data, particular attention is devoted to the Schwarzschild's limit of the four{dimensional counterpart of these electromagnetic- free solutions. Massive particles stable...
Arxiv (Free subscription) | 40 minutes ago
In connection with the study of shear-free null geodesics in Minkowski space, we investigate the real geometric effects in real Minkowski space that are induced by and associated with complex world-lines in complex Minkowski space. It was already known, in a formal manner, that complex analytic curves in complex Minkowski space induce shear-free null geodesic congruences. Here we look at the direct...
Arxiv (Free subscription) | 40 minutes ago
We report our rederivation of the equations of motion for relativistic compact binaries through the third-and-a-half post-Newtonian (3.5 PN) order approximation to general relativity using the strong field point particle limit to describe self-gravitating stars instead of the Dirac delta functional. The computation is done in harmonic coordinates. Our equations of motion describe the orbital motion...
Arxiv (Free subscription) | 40 minutes ago
The notion that the metric field in general relativity can be understood as a property of space-time rests on a feature of the theory sometimes called universal coupling -- the claim that rods and clocks "measure" the metric in a way that is independent of their constitution. It is pointed out that this feature is not strictly a consequence of the central dynamical tenets of the theory,...
Arxiv (Free subscription) | 40 minutes ago
In this talk, I describe and defend four non-standard claims about four effective field theories, and try to extract some lessons about the limits of effective field theory. The four theses (and a capsule diagnosis given in parentheses) are: 1) Kaon loops are not a reliable part of chiral perturbation theory (dimensional regularization does not know about the chiral scale), 2) Regge physics is inappropriately...
Arxiv (Free subscription) | 40 minutes ago
In hybrid inflationary models, inflation ends by a sudden instability associated with a steep ridge in the potential. Here we argue that this feature can generate a large contribution to the curvature perturbation on observable scales. This contribution is almost scale-invariant but highly non-Gaussian. The degree of non-Gaussianity can exceed current observational bounds, unless the inflationary...
Arxiv (Free subscription) | 40 minutes ago
We revisit an old idea that gravity can be unified with Yang-Mills theory by enlarging the gauge group of gravity formulated as gauge theory. Our starting point is an action that describes a generally covariant gauge theory for a group G. The Minkowski background breaks the gauge group by selecting in it a preferred gravitational SU(2) subgroup. We expand the action around this background and find...
Arxiv (Free subscription) | 40 minutes ago
We give a simple nonsupersymmetric example in which chronology protection follows from unitarity and the AdS/CFT correspondence. We consider a ball of homogeneous, rotating dust in global AdS3 whose backreaction produces a region of Goedel space inside the ball. We solve the Israel matching conditions to find the geometry outside of the dust ball and compute its quantum numbers in the dual CFT. When...
Arxiv (Free subscription) | yesterday
In this paper we present a model for 4 dimensional quantum gravity constructed using exotic smooth structure. We calculate the semi-classical expectation value of volume and correlation functions for several gravitational free-field actions and find that the results are similar, independent of the particular action that is chosen. These are first results of their kind in dimension 4, and represent...
Arxiv (Free subscription) | yesterday
We study the effect of a (3+1)-dimensional Chern-Simons electrodynamics on the equations governing the dynamics of magnetized plasma and fields. In this model, the Chern-Simons (CS) part consists of a dynamical pseudo-scalar field whose space-time derivatives couple with the electromagnetic field. We explore the CS corrections to the evolution equation for the magnetic field in a plasma with non-zero...
Arxiv (Free subscription) | yesterday
In this letter we discuss cosmological first order phase transitions with de Sitter bubbles nucleating on (inhomogeneous) matter backgrounds. The de Sitter bubble can be a toy model for an inflationary phase of universes like our own. Using the thin wall approximation and the Israel junction method we trace the classical evolution of the formed bubbles within a compound model. We first address homogeneous...
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aronaldox7 | 01/08/2009
Visit site for watching video of episode The Dumpling Paradox
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There’s only one legitimate place I’ve found to watch it, the rest seem like scams :-/ You can watch it over here though: http://www.vostuu.com/bigbangtheory.html
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stephaxml | 12/20/2008
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csomboza | 12/11/2008
On The Big Bang Theory Season 2 Episode 11 , you will notice that Christmas is stressing out Leonard because his handsome colleague is now dating Penny and Leonard together with his friends are bothered by Sheldon’s obsession of giving presents for Christmas.
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