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To try to illustrate the concept, the Max Planck Institute for Gravitational Physics made the accompanying movie of "Quantum Spin Dynamics in Loop Quantum Gravity." It depicts the quantum evolution of geometry in Loop Quantum Gravity

Thanks for posting this, Joseph. Very funny!

Parody of "intelligent design" science education advocates.

For several decades, astronomers and cosmologists have been piling up data that indicates most of the matter in the Universe is dark, interacting only via gravity. As modified theories of gravity failed to account for observation, candidates for dark mater were winnowed down until one remained in favor: the weakly interactive massive particle, or WIMP. Over the past several years, potential signals of WIMPs have appeared in space and on Earth; that, combined with the startup of the LHC, has given the research community the sense that it's close to pinning down the identity of the WIMPs. But a review in this week's Nature considers what might happen if we fail.

Some scenarios with Lorentz Invariance Violation (LIV) motivated by quantum gravity do predict an energy dependence in the travel time of photons.

A small change to the theory of gravity implies that our universe inherited its arrow of time from the black hole in which it was born.

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

High performance liquid chromatography is known as high-pressure liquid chromatography. HPLC is an extremely improved version of chromatography, where the solvent is allowed to drip through the column under gravity.

Though an experiment hunting for gravitational waves has yet to find any, its null result helps constrain models of how the universe began.

Potential for plate tectonics on extrasolar planets to create conditions suitable for the development of life

ientists are claiming a stunning discovery in their quest to fully understand gravity.They have observed the warping of space-time generated by the collision of two black holes more than a billion light-years from Earth.The international team says the first detection of these gravitational waves will usher in a new era