SciAm article on Hořava-Lifshitz gravity

[jamesr]

I just saw this article from Scientific American: http://www.scientificamerican.com/article.cfm?id=splitting-time-from-space

Here are some links to the relavent papers:
On the Extra Mode and Inconsistency of Hořava Gravity, D. Blas, O. Pujolàs, S. Sibiryakov, 2009
Quantum Gravity at a Lifshitz Point, Petr Hořava 2009

One aspect that caught my eye is that the universe did not bang it bounced.
From Robert Brandenberger’s August paper:http://arxiv.org/pdf/0904.2835
Abstract
Hořava-Lifshitz gravity, a recent proposal for a UV-complete renormalizable gravity theory, may lead to a bouncing cosmology. In this article we argue that Hořava-Lifshitz cosmology may yield a concrete realization of the matter bounce scenario and thus give rise to an alternative to inflation for producing a scale-invariant spectrum of cosmological perturbations. In this scenario, quantum vacuum fluctuations exit the Hubble radius in the prebounce phase, and the spectrum is transformed into a scale-invariant one on super-Hubble scales before the bounce because the long wavelength modes undergo squeezing of their wave functions for a longer period of time than shorter wavelength modes. The scale invariance of the spectrum of curvature fluctuations is preserved during and after the bounce. A distinctive prediction of this scenario is the amplitude and shape of the bispectrum.

[pluto]

G’day

Knowing how matter contracts and expands is a cyclic process that is ongoing and does not apply to the total form of the universe.

We see this in star formation
We see this in cluster of stars
We see this in galaxy evolution
We see this in cluster of clusters of galaxies with an AGN that forms a megagiant jet ejecting matter and reforming its own galaxy form and galaxies afar.

http://chandra.harvard.edu/photo/2003/cenajet/
Centaurus A Jet:
Energetic Jet Meets Resistance In Nearby Galaxy

Jets such as the one in Centaurus A Jet are widespread phenomena in the cosmos, and represent one of the primary means for extracting energy from the vicinity of a black hole. Some jets extend over distances of a million light years. They represent a major energy source for the galaxy and are thought to affect the evolution of the host galaxy and its surroundings. The Centaurus A Jet image will help scientists to understand the effects of jets on their environment.

http://chandra.harvard.edu/photo/2001/0134/
M87 Jet:
Chandra Sheds Light on the Knotty Problem of the M87 Jet

Quasars & Active Galaxies :: Galaxies with unusually energetic activity, including high-energy jets, that is related to a central supermassive black hole.
http://chandra.harvard.edu/press/category/quasars.html

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