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By proving a single photon can't travel faster than light, scientists say they have proven time travel is impossible. THE GIST Hong Kong physicists say they have proven a single photon cannot travel faster than the speed of light. This demonstrates that time travel is impossible, they say. Hong Kong physicists say they have proved that a single photon obeys Einstein's theory that nothing can travel faster than the speed of light — demonstrating that outside science fiction, time travel is impossible. The Hong Kong University of Science and Technology research team led by Du Shengwang said they had...

A black-hole system in a neighboring galaxy is twice as bright as astronomers had thought possible, a new study reports. The incredible luminosity of the system in question, which resides about 22 million light-years from Earth in the Pinwheel Galaxy, may force a rethink of the theories that explain how some black holes radiate energy, researchers said.

Black holes are staples of science fiction and many think astronomers have observed them indirectly. But according to a physicist at the Lawrence Livermore National Laboratory in California, these awesome breaches in space-time do not and indeed cannot exist. Over the past few years, observations of the motions of galaxies have shown that some 70% the Universe seems to be composed of a strange 'dark energy' that is driving the Universe's accelerating expansion. George Chapline thinks that the collapse of the massive stars, which was long believed to generate black holes, actually leads to the formation of stars that contain...

Stephen Hawking has shocked physicists by admitting “there are no black holes”. In a paper published online, Professor Hawking instead argues there are “grey holes”. “The absence of event horizons means that there are no black holes—in the sense of regimes from which light can't escape to infinity,” he says in the paper, called Information Preservation and Weather Forecasting For Black Holes.He says that the idea of an event horizon, from which light cannot escape, is flawed. He suggests that instead light rays attempting to rush away from the black hole’s core will be held as though stuck on a...

A collaboration of researchers at the U.S department of energy (DOE)’s Lawrence Berkeley national laboratory (Berkeley Lab) has discovered that sodium bismuthide can exist as a form of quantum matter called a three-dimensional topological Dirac semi-metal (3DTDS). This is the first experimental confirmation of 3D Dirac fermions in the interior or bulk of a material, a novel state that was only recently proposed by theorists.

In a paper published in the current issue of the scientific journal Nature Communications and titled "Direct measurement of a 27-dimensional orbital-angular-momentum state vector," a team of physicists led by the University of Rochester's Mehul Malik describe how they circumvented a basic principle of uncertainty that requires that some states of a quantum system must be understood poorly if other states are to be understood well. Determining a quantum state, such as the position of an electron or the momentum of a photon, is tricky, to say the least. That's because subatomic particles behave nothing at all like billiard balls,...

2. The Golden Ratio & Fibonacci Numbers: Fact versus Fiction VIDEO (October 8, 2012) Professor Keith Devlin dives into the topics of the golden ratio and fibonacci numbers. Originally presented in the Stanford Continuing Studies Program

The Milky Way’s black hole is about to gobble up its first dinner, and astronomers are hoping to have front row seats when it happens. A huge gas cloud, about three times the mass of Earth, is on course to collide with the supermassive black hole at the heart of our galaxy in March. Astronomers expect the gas cloud will swing so close to the black hole that it will heat up to the point where it produces spectacular X-rays.

FOR many years, Perth chemistry and physics teacher Marko Vojkovic has been at the front of the fight against what he describes as sociology in the teaching of sciences. He led opposition to Western Australia's ill-fated outcomes-based education curriculum in 2007 and says he recognised some of its telltale signs when teachers got their first glimpses of the national curriculum in 2010. For example, the edict that sustainability, the Asian century and indigenous perspective should be taught as part of physics and chemistry did not sit well with Mr Vojkovic. "I don't think there's a particularly Asian way of looking...

Researchers from Michigan have scoured websites, search engine results and social networks dating back as far as 1996 in search of people who discussed select events before they happened. They even asked time travellers from the future to tweet using a specific hashtag. Yet despite comprehensive analysis of thousands of records, they were unable to find any evidence time travellers existed.

Big-bang-defying giant of astronomy passes away by John G. Hartnett Published: 31 December 2013 (GMT+10) Halton Arp passed away on Saturday morning 28th December 2013 in Munich, Germany. He will be sorely missed by many but not so much by others because of his challenges to the ruling big bang paradigm. With Geoffrey Burbidge and others, Professor Halton Arp was a thorn in the side of those who held to the standard story line of the big bang. In many papers and several books1 he promoted the idea that quasars are born from the nucleus of active galaxies—parent galaxies. In...

Original Title:Hubblecast 70 Explains How Gravitational Lensing Will Help Uncover the Secrets of the Universe This eight minute Hubblecast video takes a look at gravitational lensing, explaining how it works and how it can help astronomers uncover the secrets of the Universe.

Rapatronic Nuclear Photographs-Images Taken Within 10 Nano-Seconds of Nuclear Detonation Click Here:The Camera That Captured the First Millisecond of a Nuclear Bomb Blast Wikipedia:Rapatronic Camera From Wikipedia, the Free Encyclopedia Nuclear explosion photographed by rapatronic camera less than 1 millisecond after detonation. From the Tumbler-Snapper test series in Nevada, 1952. The fireball is about 20 meters in diameter in this shot. The spikes at the bottom of the fireball are known as the rope trick effect. The rapatronic camera (a contraction of rapid action electronic) is a high-speed camera capable of recording a still image with an exposure time as...

Using the South Pole Telescope, scientists observed patterns known as "B-modes," which occur when a massive object bends a light source, like a lens. These B-modes interacted with matter from very early in the history of the universe, some 400,000 years after the Big Bang. John Carlstrom, the S. Chandrasekhar Distinguished Service Professor in Astronomy & Astrophysics at the University of Chicago, lead the research team. The multi-institutional team published their work Sept. 30 in the journal Physical Review Letters. "The detection of B-mode polarization by South Pole Telescope is a major milestone, a technical achievement that indicates exciting physics...

A research team from the University of Singapore has developed a device that can make objects invisible by bathing them in a beam of darkness. The system takes the conventional approach to optics -- which generally aims to make images as sharp and clear as possible -- and turns it completely on its head. Usually imaging systems focus light into a pattern known as a point spreading function, which consists of a spiked central region of high intensity (the main lobe) surrounded by a concentric region of lower intensity light and a higher intensity lobe after this. In order to...

To think that our universe is 13.8 billion years old is incredible enough. But now researchers are proposing that the universe stretches back into time infinitely with no singular point where it started. The idea is one possible result of something known as ‘rainbow gravity’- a theory that is not widely accepted among physicists, though many say the idea is interesting. The theory’s name comes from a suggestion that gravity's effect on the cosmos is felt differently by varying wavelengths of light, which can be found in the colours of the rainbow. The theory was proposed 10 years ago in...

There’s a web post from the Nature website going around entitled “Simulations back up theory that Universe is a hologram.” It’s an interesting concept, but suffice it to say, the universe is not a hologram, certainly not in the way people think of holograms. So what is this “holographic universe” thing? ... From this you get a headline implying that we live in a hologram. On twitter, Ethan Siegel proposed a more sensible headline: “Important idea of string theory shown not to be mathematically inconsistent in one particular way”.

The universe could be about to collapse, and everything in it—including us—will be compressed into a small, hard ball. The process may already have started somewhere in our cosmos and is eating away at the rest of the universe, according to theoretical physicists. The mind-bending concept has been around for a while, but now researchers in Denmark claim they have proven it is possible with mathematical equations. …

High-temperature superconductors exhibit a frustratingly varied catalog of odd behavior, such as electrons that arrange themselves into stripes or refuse to arrange themselves symmetrically around atoms. Now two physicists propose that such behaviors – and superconductivity itself – can all be traced to a single starting point, and they explain why there are so many variations. This theory might be a step toward new, higher-temperature superconductors that would revolutionize electrical engineering with more efficient motors and generators and lossless power transmission. -snip- Most subatomic particles have a tiny magnetic field – a property physicists call "spin" – and electrical resistance...

Sherwyn Sarabi scored an IQ of 160, just like Albert Einstein, Bill Gates, and Stephen Hawking. The British boy is already studying at the level of a 9-year-old and has read over 190 books. A four-year-old boy has stunned psychologists—after intelligence tests revealed him to have the same IQ as Einstein. Sherwyn Sarabi has tested off the scale for intelligence—scoring an IQ of 160—the highest mark on the test. It's the same score that experts believe scientist Einstein had, as well as being identical to that of Bill Gates and Stephen Hawking. Sherwyn from Barnsley, Yorks, started school two years...