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Physicists have proposed an experiment that could force us to make a choice between extremes to describe the behaviour of the Universe. The proposal comes from an international team of researchers from Switzerland, Belgium, Spain and Singapore, and is published today in Nature Physics. It is based on what the researchers call a 'hidden influence inequality'. This exposes how quantum predictions challenge our best understanding about the nature of space and time, Einstein's theory of relativity. "We are interested in whether we can explain the funky phenomena we observe without sacrificing our sense of things happening smoothly in space and...

Scientists create never-before-seen form of matter Photons with strong mutual attraction in a quantum nonlinear medium. Harvard and MIT scientists are challenging the conventional wisdom about light, and they didn't need to go to a galaxy far, far away to do it. Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25...

Almost a century ago, renowned quantum theorist Werner Heisenberg found fundamental limits on how well a quantum system can be prepared and measured, known as Heisenberg's uncertainty principle. However, only the limit that pertains to the preparation of quantum systems has been quantified; the other two, relating to measurements, have long been a matter of debate, lacking a formal treatment. These limits are: That it is impossible to jointly measure incompatible quantities, for instance, location and speed of a quantum object, with perfect accuracy; and that a measurement of one of these quantities necessarily disturbs the other. Last year, UQ's...

Team found that Polaris is 2.5 times brighter today than in 137CE Experts say find is 'entirely unexpected' Astronomers have discovered that Polaris, the north star, is getting brighter. They say the star has suddenly reversed two decades of dimming. It is expanding at more than 100 times the rate they expected - and nobody is sure why. A team led by Scott Engle of Villanova University in Pennsylvania recalibrated historic measurements of Polaris by Ptolemy in 137 C.E., the Persian astronomer Al-Sufi in 964 C.E., and others. They investigated the fluctuations of the star over the course of several...

Black holes can radiate in a way that agrees with thermodynamics, and the region near the event horizon doesn’t have a firewall, just as general relativity requires. So Hawking’s proposal is a solution to a problem that doesn’t exist.

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...