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A gigantic, previously unknown set of galaxies has been found in the distant universe, shedding light on the underlying skeleton of the cosmos. "Matter is not distributed uniformly in the universe," said Masayuki Tanaka, an astronomer with the European Southern Observatory (ESO) who helped discover the galactic assemblage. "In our cosmic vicinity, stars form in galaxies and galaxies usually form groups and clusters of galaxies." But those collections of matter are just small potatoes compared to larger structures long-theorized to exist. "The most widely accepted cosmological theories predict that matter also clumps on a larger scale in the so-called 'cosmic...

Rethinking relativity: Is time out of joint? EVER since Arthur Eddington travelled to the island of Príncipe off Africa to measure starlight bending around the sun during a 1919 eclipse, evidence for Einstein’s theory of general relativity has only become stronger. Could it now be that starlight from distant galaxies is illuminating cracks in the theory’s foundation? .... Yet it is still not clear how well general relativity holds up over cosmic scales, at distances much larger than the span of single galaxies. Now the first, tentative hint of a deviation from general relativity has been found. While the evidence...

As we recently noted, Stephen Hawking has stepped down from the Lucasian Chair at Cambridge. The chair didn't stay empty for long. It has been announced that Michael Green will become the new Lucasian Professor. Green is one of the pioneers of string theory, and is already at Cambridge. I'm not sure he even switches offices, or chairs for that matter. Hawking did seminal work in general relativity. He proved a number of singularity theorems (with Roger Penrose). He wrote The Large Scale Structure of Spacetime (with George Ellis). John Wheeler conjectured that quiescent black holes have "no hair" (i.e.,...

As promised, Brian Cox was on The Colbert Report last night, and hit it out of the park. The whole show was better than average (which is saying a lot) but Brian truly rocked! If you missed it (and live in the States) the whole episode is online (Brian's segment is about 13:50 into the episode). Comedy Central won't allow embedding the whole show (sigh), and Brian's segment isn't separated out on the CC site, but right before he was on Colbert ragged on physics and the LHC... In the full segment, they talk about Brian's book Why E=mc2, which...

When the Fermi team did the calculations, using the most conservative estimates for how astrophysics plays into this, they determined that the mass scale must be at least 1.2 times the Planck mass, and by using reasonable but less conservative assumptions, they derived lower limits on the mass scale of up to 100 times the Planck mass. One way to interpret this is to say that there is no variation of the speed of light coming from any quantum gravity effects at less than 1.2 times the Planck mass. And given that some quantum gravity frameworks predict that effects should...

PARIS (AFP) – It took 13 billion years to reach Earth, but astronomers have seen the light of an exploding mega-star that is the most distant object ever detected, two studies published Thursday reported. The stunning gamma-ray burst (GRB) was observed by two teams of researchers in April, and opens a window onto a poorly known period when the Universe was in its infancy.

Crystals that can confine both light and vibrations could create better biosensors.The crystal traps vibrations and light in the same place.Eichenfield M., et al. Light and mechanical vibrations have been imprisoned together for the first time ever in the same place. An artificial crystal that traps both could lead to ultra-sensitive biosensors, create an interface for devices on a chip and provide an elegant cooling mechanism to help test quantum limits. The communications industry has long used specially patterned materials, called photonic crystals, to guide light through optical fibres. Similar structures, known as phononic crystals, manipulate mechanical vibrations and are...

Enlarge ImageBoom! After being hit with laser beams, a small plastic pellet (sunlike object) emits x-rays, some of which bombard a pellet of silicon (blue and purple). Credit: Adapted from S. Fujioka et al., Nature Physics, Advance Online Publication A team of researchers has created conditions analogous to those found outside of a black hole by blasting a plastic pellet with high-energy laser beams. The advance should sharpen insights into the behavior of matter and energy in extreme conditions. Astronomers can't observe black holes directly because their immense gravity won't let light escape. Instead, they have focused on what...

PARIS — For decades, scientists have dreamed about turning thorium — an element that is less radioactive and produces less nuclear waste than uranium — into an alternative fuel for nuclear energy. Recent technological developments may be bringing the dream closer to reality. As a naturally occurring metal that is substantially more abundant than uranium, its most common isotopic form, thorium-232, can be converted by irradiation to uranium-233, which is suitable for use in nuclear fuels. The United States is estimated to have 400,000 tons of thorium, Turkey 344,000 tons and India 319,000 tons, according to a 2008 joint report...

Mini-hole made of metamaterials ensnares microwave light.The artificial 'black hole' sucks up microwaves.Q. Cheng and T. J. Cui Physicists have created a black hole for light that can fit in your coat pocket. Their device, which measures just 22 centimetres across, can suck up microwave light and convert it into heat. The hole is the latest clever device to use 'metamaterials', specially engineered materials that can bend light in unusual ways. Previously, scientists have used such metamaterials to build 'invisibility carpets' and super-clear lenses. This latest black hole was made by Qiang Chen and Tie Jun Cui of Southeast University...

The strongest limit on the number of possible universes is the human ability to distinguish between different universes. (PhysOrg.com) -- Over the past few decades, the idea that our universe could be one of many alternate universes within a giant multiverse has grown from a sci-fi fantasy into a legitimate theoretical possibility. Several theories of physics and astronomy have hypothesized the existence of a multiverse made of many parallel universes. One obvious question that arises, then, is exactly how many of these parallel universes might there be. In a new study, Stanford physicists Andrei Linde and Vitaly Vanchurin have calculated...

In the past 5 years, no material has excited more interest from condensed matter physicists than graphene, a sheet of carbon only one atom thick. Electrons zing through the stuff in an unusual way, and they flow so easily that graphene could someday replace silicon and other semiconductors as the material of choice for microchips. Now, a team of physicists has taken a key step in fulfilling graphene's promise as a hotbed of exotic physics by showing that the electrons within it can team up to behave like particles with a fraction of the electron's charge. The effect is called...

In the murky boundary between our solar system and the rest of the galaxy, scientists have spotted a bright band of surprising high-energy emissions. The results come from the first all-sky map created by NASA's new Interstellar Boundary Explorer (IBEX) spacecraft, which launched in October 2008. While orbiting Earth, IBEX monitors incoming neutral atoms that originate billions of miles away at the solar system's edge to learn about the interaction between the sun and the cold expanse of space. "The IBEX results are truly remarkable, with emissions not resembling any of the current theories or models of this never-before-seen region,"...

Two physicists speculate God—or "time agents from the future"—shut it down to keep them from discovering the God Particle. REPORTER'S NOTE: I've come across a lot of quirky articles in publishing intriguing news, but this rates up there with the most odd of all. What is odd, is that two such brilliant scientists would publicly proclaim their hypothesis that God not only exists, but interevened in their scientific endeavors. Wow. Not only that, but the addendum—that it could have been God OR "time agents from the future"—made me wonder. If these men were schooled in the divine supernatural, they may...

Scientists have generated a magnetic version of electricity, which they have called magnetricity. The discovery marks an important advance in theoretical physics. The existence of magnetic “charges” has been predicted for nearly 70 years but has never been observed in practice. The study was led by Professor Steve Bramwell, of the London Centre for Nanotechnology. He said: “It is not often in the field of physics you get the chance to ask, ‘How do you measure something?’, and then go on to prove a theory unequivocally. This is a very important step to establish that magnetic charge can flow like...

An electromagnetic "black holeMovie Camera" that sucks in surrounding light has been built for the first time. The device, which works at microwave frequencies, may soon be extended to trap visible light, leading to an entirely new way of harvesting solar energy to generate electricity. A theoretical design for a table-top black hole to trap light was proposed in a paper published earlier this year by Evgenii Narimanov and Alexander Kildishev of Purdue University in West Lafayette, Indiana. Their idea was to mimic the properties of a cosmological black hole, whose intense gravity bends the surrounding space-time, causing any nearby...

Its discoveries could be so "abhorrent to nature" that they are coming back to stop their own creation. Forget the far-fetched belief that it will create a black hole, two distinguished physicists have gone even further claiming nature itself is stopping the troubled £4.4billion project from getting off the ground. In a theory reminiscent of the time travelling film Back to the Future, the theoretical physicists Holger Nielsen, from Denmark, and Masao Ninomiya, from Japan, have concluded that its discoveries could be so "abhorrent to nature" that they are coming back to stop their own creation. They have outlined their...

This article is also available as a podcast. A Gömböc is a strange thing. It looks like an egg with sharp edges, and when you put it down it starts wriggling and rolling around with an apparent will of its own. Until quite recently, no-one knew whether Gömböcs even existed. Even now, Gábor Domokos, one of their discoverers, reckons that in some sense they barely exists at all. So what are Gömböcs and what makes them special? Balancing act The defining feature of a Gömböc is the fact that it's got just two points of equilibrium: one is stable and...

Can we calculate the gravitational field of a mass moving close to the speed of light? Franklin Felber (Starmark Inc) believes he can, with implications for propulsion. Back in 2006 we looked briefly at Felber’s work, describing what the physicist believes to be a repulsive gravitational field that emerges from his results. Felber discussed the matter at the Space Technology and Applications International meeting that year, where he presented his calculations of the ‘relativistically exact motion of a payload in the gravitational field of a source moving with constant velocity.’ Above a certain critical velocity, Felber believes, any mass...

A French physicist with the European atomic research centre near Geneva was charged with terrorism offences by a Paris judge last night after investigators said that he offered to work with the North African branch of al-Qaeda. Adlène Hicheur, 32, who is of Algerian origin, was arrested last week with his younger brother after intelligence agents intercepted his alleged internet contacts with al-Qaeda in the Islamic Maghreb. The physicist, who works at the giant atomic collider at CERN (European Organisation for Nuclear Research), which straddles Swiss and French territory, told the Islamic group that he was interested in committing an...