How Bacteria Could Generate Radio waves

Can bacteria generate radio waves?

On the face of it, this seems an unlikely proposition. Natural sources of radio waves include lightning, stars and pulsars while artificial sources include radar, mobile phones and computers. This is a diverse list. So it's hard to see what these things might have in common with bacteria that could be responsible for making radio waves.

But today, Allan Widom at Northeastern University in Boston and a few pals, say they've worked out how it could be done.

They point out that many types of bacterial DNA take the form of circular loops. So they've modelled the behaviour of free electrons moving around such a small loop, pointing out that, as quantum objects, the electrons can take certain energy levels.

Widom and co calculate that the transition frequencies between these energy levels correspond to radio signals broadcast at 0.5, 1 and 1.5 kilohertz. And they point out that exactly this kind of signal has been measured in E Coli bacteria.

Let's make one thing clear: this is a controversial area of science. The measurements of bacterial radio waves were published in 2009 by Luc Montagnier, who won the Nobel Prize for medicine in 2008 for the discovery of HIV. However, Montagnier is a controversial figure and it's fair to say that his claims are not accepted by most mainstream biologists.

However, one of the criticisms of the work was that there is no known mechanism by which bacteria can generate radio waves. That criticism may now no longer hold.

That means Widom and co may be able to kickstart more work in this area. It is well known that bacterial and other types of cells use electromagnetic waves at higher frequencies to communicate as well as to send and store energy. If cells can also generate radio waves, there's no reason to think they wouldn't exploit this avenue too.

via How Bacteria Could Generate Radio waves - Technology Review.

Time Was Never the 4th Dimension

Time is not the fourth dimension of spacetime, nor is it an absolute quantity that flows on its own, Slovenian researchers say. Instead, they propose that time is simply a measure denoting the numerical order of change.

This new theory is based on the fact that not even famed physicist Albert Einstein believed that time (t) was the fourth dimension. In other words, when we look at space, we shouldn't see three dimensions (3D) plus time, but rather four dimensions (4D).

According to the new proposal, time can only be used to measure numerical order of material change, and not to explain other phenomena that go on in the material world. The new study was conducted by investigators at the Scientific Research Center Bistra (SRCB), in Ptuj.

By looking at the Universe from this perspective, the team argues, explaining quantum information transfers become a lot easier. A 4D space provides the best possible medium for such transfers.

One of the primary arguments in the new proposal is that time has absolutely no primary physical existence. It is, in fact, simply a mathematical value, that we use to measure the frequency and speed of an object.

In this respect, using t as the value of a X-axis on a graph is incorrect, since we cannot measure time itself. The idea is expanded on in two research papers, one of which was published in the journal Physics Essays. The other will appear in an upcoming issue of the same magazine.

The proposal basically calls for a paradigm shift in this area of research. The studies argue experts should regard spacetime as having four dimensions of space. The main implication of this is that the Universe is truly timeless, Daily Galaxy reports.

“Minkowski space is not 3D + T, it is 4D. ... “This view corresponds better to the physical world and has more explanatory power in describing immediate physical phenomena: gravity, electrostatic interaction, information transfer,” they add.

“The idea of time being the fourth dimension of space did not bring much progress in physics and is in contradiction with the formalism of special relativity,” Sorli goes on to say.

“We are now developing a formalism of 3D quantum space based on Planck work. It seems that the Universe is 3D from the macro to the micro level to the Planck volume, which per formalism is 3D,” the investigator adds.

“In this 3D space there is no ‘length contraction,’ there is no ‘time dilation.’ What really exists is that the velocity of material change is ‘relative’ in the Einstein sense,” he concludes.


via Time Was Never the 4th Dimension - Softpedia.

Chemists fabricate 'impossible' material

When atoms combine to form compounds, they must follow certain bonding and valence rules. For this reason, many compounds simply cannot exist. But there are some compounds that, although they follow the bonding and valence rules, still are thought to not exist because they have unstable structures. Scientists call these compounds "impossible compounds." Nevertheless, some of these impossible compounds have actually been fabricated (for example, single sheets of graphene were once considered impossible compounds). In a new study, scientists have synthesized another one of these impossible compounds -- periodic mesoporous hydridosilica -- which can transform into a photoluminescent material at high temperatures.

The researchers, led by Professor Geoffrey Ozin of the Chemistry Department at the University of Toronto, along with coauthors from institutions in Canada, China, Turkey, and Germany, have published their study in a recent issue of the Journal of the American Chemical Society.

Like graphene, periodic mesoporous hydridosilica (meso-HSiO1.5) consists of a honeycomb-like lattice structure. Theoretically, the structure should be so thermodynamically unstable that the mesopores (the holes in the honeycomb) should immediately collapse into a denser form, HSiO1.5, upon the removal of the template on which the material was synthesized.

In their study, the researchers synthesized the mesoporous material on an aqueous acid-catalyzed template. When they removed the template, they discovered that the impossible material remains stable up to 300 °C. The researchers attribute the stability to hydrogen bonding effects and steric effects, the latter of which are related to the distance between atoms. Together, these effects contribute to the material’s mechanical stability by making the mesopores resistant to collapse upon removal of the template.

“The prevailing view for more than 50 years in the massive field of micro-, meso-, or macroporous materials is that a four-coordinate, three-connected open framework material (called disrupted frameworks) should be thermodynamically unstable with respect to collapse of the porosity and therefore should not exist,” Ozin told PhysOrg.com. ...

via Chemists fabricate 'impossible' material.

Heaviest antimatter found

... a three-dimensional rendering of the STAR time projection chamber surrounded by the time-of-flight barrel (the outermost cylinder). Particle tracks spray out from the collision, including a meter-long track from an antihelium-4 nucleus (highlighted in bold red)

The reports began circulating a few weeks ago, and today's publication in the journal Nature makes it official: Physicists have detected the heaviest bits of antimatter ever found on Earth. And that record is likely to stand for a long, long time.

Members of the STAR collaboration at the Relativistic Heavy Ion Collider, based at Brookhaven National Laboratory in New York, say they've seen the traces of 18 nuclei of antihelium-4 among about half a trillion particles produced by almost a billion gold-ion collisions at RHIC. These nuclei are like regular helium nuclei, except that instead of having two protons and two neutrons, they have two negatively charged antiprotons and two antineutrons.

The particles existed for only about 10 billionths of a second before they came in contact with ordinary matter particles and were annihilated, but that was long enough to register on STAR's detectors. Physicists can routinely produce antihydrogen nuclei (basically, antiprotons), and last year a research team reported the first detection of antihydrogen atoms (a positron going around an antiproton). Scientists have even detected antihelium-3 nuclei (two antiprotons and an antineutron). But until now, antihelium-4 has eluded them.

RHIC is best-known for smashing together gold ions so forcefully that particles like protons shatter into their constituent quarks and gluons, producing the kind of primordial soup that existed just an instant after the big bang. When that soup congeals, all sorts of combinations of quarks come together — and statistically, there's an ever-so-slight chance that the quarks will arrange themselves into two antiprotons paired with two antineutrons. The odds of that happening are so vanishingly small that RHIC's researchers had to sift through mountains of data to find the 18 events they were looking for.

The bad news is that the chances of finding anything even heavier are even more vanishingly small. So small, in fact, that physicists don't expect to detect them anytime in the foreseeable future, at RHIC or even at Europe's Large Hadron Collider.

The good news is that these 18 detections confirm the statistical model that theorists expected to see for the creation of antimatter in the lab.

Searching for natural-born antimatter in outer space is one of the top jobs for the $2 billion Alpha Magnetic Spectrometer, which is due to be delivered to the International Space Station a week from now. The AMS should be able to detect antihelium nuclei and other subatomic oddities during its years-long run in orbit.

via Cosmic Log - It's official: Heaviest antimatter found.

Do Aliens Speak Particle-Tongue?

Extraterrestrials may have a better way to communicate across space than radio waves or optical beams. A team of scientists suggests ET could encode neutrinos, for example.

These particles of matter are similar to electrons, but since they have no electric charge, they can pass through anything. This makes them ideal for long-distance travel, as neutrinos are undisturbed by gas, dust and other matter that can block radio waves and other types of electromagnetic radiation.

Astronomers have been scouring the galaxy for decades for alien-produced radio signals -- and more recently for non-naturally occurring light pulses, as well -- to no avail.

"We really have no clue as to how some advanced civilization might want to transmit to us, nor do we have any really good idea why they would want to transmit to us," physicist John Learned, with the University of Hawaii, told Discovery News.

"Everything that we're doing is exploratory science: You don't know the game; you don't know if you're in the game; you don't know the rules of the game... which is what makes it so much fun," said Learned, who, along with colleagues, has written a series of articles about how neutrinos could be used for communication.

ET could, for example, send out a neutrino beam at precise (and non-naturally occurring) energy levels that would be sure to catch a scientist's eye.

"If there's a civilization, like our civilization, which is at the stage of setting up large neutrino detectors, then one would see this signal of a unique signature and you would right away say: 'What the heck is going on here? This is certainly not a natural signature.' This is something that would really get your attention on the very first (detection.) ...

via Do Aliens Speak Particle-Tongue? : Discovery News.

Did the early universe have one dimension? Scientists outline test for theory

Did the early universe have just one spatial dimension?

That's the mind-boggling concept at the heart of a theory that University at Buffalo physicist Dejan Stojkovic and colleagues proposed in 2010.

They suggested that the early universe -- which exploded from a single point and was very, very small at first -- was one-dimensional (like a straight line) before expanding to include two dimensions (like a plane) and then three (like the world in which we live today).

The theory, if valid, would address important problems in particle physics.

Now, in a new paper in Physical Review Letters, Stojkovic and Loyola Marymount University physicist Jonas Mureika describe a test that could prove or disprove the "vanishing dimensions" hypothesis.

Because it takes time for light and other waves to travel to Earth, telescopes peering out into space can, essentially, look back into time as they probe the universe's outer reaches.

Gravitational waves can't exist in one- or two-dimensional space. So Stojkovic and Mureika have reasoned that the Laser Interferometer Space Antenna (LISA), a planned international gravitational observatory, should not detect any gravitational waves emanating from the lower-dimensional epochs of the early universe. ...

Because the planned deployment of LISA is still years away, it may be a long time before Stojkovic and his colleagues are able to test their ideas this way.

However, some experimental evidence already points to the possible existence of lower-dimensional space.

Specifically, scientists have observed that the main energy flux of cosmic ray particles with energies exceeding 1 teraelectron volt -- the kind of high energy associated with the very early universe -- are aligned along a two-dimensional plane.

If high energies do correspond with lower-dimensional space, as the "vanishing dimensions" theory proposes, researchers working with the Large Hadron Collider particle accelerator in Europe should see planar scattering at such energies.

Stojkovic says the observation of such events would be "a very exciting, independent test of our proposed ideas." ...

via Primordial weirdness: Did the early universe have one dimension? Scientists outline test for theory.

Mysterious Pioneer Anomaly, Likely Solved

The debate has been raging ever since an astronomer named John Anderson first noticed the anomaly in 1980. Anderson created an impossibly complicated algorithm so that he and other JPL scientists could use the radio transmission data to study gravitational effects in the outer solar system.

But it didn't seem to work. Or rather, he noticed a small discrepancy between the Doppler shifts predicted by his algorithm, and the actual shifts being measured in the radio signals coming from the Pioneer spacecraft.

Dark Matter Drag?

The discrepancy is 10 billion times smaller than the acceleration due to gravity, but it was unmistakably there in Anderson's calculations. (The canonical number, for those who care, is 8.74 x 10-10 m/s2.)

What could be causing this discrepancy? Theories have abounded over the years. One popular hypothesis is that there are huge quantities of dark matter -- as yet undetected -- hanging around in the universe and exerting a little extra drag on the spacecraft, thereby slowing them down.

Another possible explanation is that gravity doesn't follow an inverse square law as formulated by Isaac Newton; this falls under the rubric of MOND (MOdified Newtonian Dynamics), the focus of a flurry of technical papers over the last 10-15 years. It's among the alternatives to dark energy to explain the fact that the expansion of our universe is accelerating.

Evidence for this hypothesis appeared to be bolstered in 1994, when Los Alamos cosmologist Michael Martin Nieto noticed that the value for the deviations of the Pioneer spacecraft was almost exactly equivalent to cosmic acceleration (the speed of light multiplied by Hubble's constant).

For Nieto, and others who noticed this strange coincidence, "The Pioneer anomaly could be the first evidence that gravity deviates from an inverse square dependence," he told Popular Science last year. "It could be huge." ...

On the more mundane side of things, there was always the possibility that the culprit might just be heat. Specifically, heat from the plutonium inside the spacecrafts' generators, some of which got converted into electricity while the rest of it radiated into space. If it did so unevenly, radiating more heat in one direction than in another -- only a 5 percent difference is required -- that might be sufficient to give rise to the Pioneer anomaly. ...

Previous calculations have only estimated the effect of reflections. So Francisco and co used a computer modeling technique called Phong shading to work out exactly how the the emitted heat is reflected and in which direction it ends up traveling.

Phong shading was dreamt up in the 1970s and is now widely used in many rendering packages to model reflections in three dimensions. It was originally developed to handle the reflections of visible light from 3D objects but it works just as well for infrared light, say Francisco and co.

In particular, Phong shading has allowed the Portuguese team to include for the first time the effect of heat emitted from a part of the spacecraft called the main equipment compartment. It turns out that heat from the back wall of this compartment is reflected from the back of the spacecraft's antenna. Since the antenna points Sunward, towards Earth, reflections off its back would tend to decelerate the spacecraft. "The radiation from this wall will, in a first iteration, reflect off the antenna and add a contribution to the force in the direction of the sun."


via Mysterious Pioneer Anomaly May Finally Be Solved : Discovery News.

I was really hoping for some momentous variation in the force of gravity, but it seems that possibility with regard to the Pioneer data, has been vanquished.

Mysterious Pioneer Anomaly, Likely Solved

The debate has been raging ever since an astronomer named John Anderson first noticed the anomaly in 1980. Anderson created an impossibly complicated algorithm so that he and other JPL scientists could use the radio transmission data to study gravitational effects in the outer solar system.

But it didn't seem to work. Or rather, he noticed a small discrepancy between the Doppler shifts predicted by his algorithm, and the actual shifts being measured in the radio signals coming from the Pioneer spacecraft.

Dark Matter Drag?

The discrepancy is 10 billion times smaller than the acceleration due to gravity, but it was unmistakably there in Anderson's calculations. (The canonical number, for those who care, is 8.74 x 10-10 m/s2.)

What could be causing this discrepancy? Theories have abounded over the years. One popular hypothesis is that there are huge quantities of dark matter -- as yet undetected -- hanging around in the universe and exerting a little extra drag on the spacecraft, thereby slowing them down.

Another possible explanation is that gravity doesn't follow an inverse square law as formulated by Isaac Newton; this falls under the rubric of MOND (MOdified Newtonian Dynamics), the focus of a flurry of technical papers over the last 10-15 years. It's among the alternatives to dark energy to explain the fact that the expansion of our universe is accelerating.

Evidence for this hypothesis appeared to be bolstered in 1994, when Los Alamos cosmologist Michael Martin Nieto noticed that the value for the deviations of the Pioneer spacecraft was almost exactly equivalent to cosmic acceleration (the speed of light multiplied by Hubble's constant).

For Nieto, and others who noticed this strange coincidence, "The Pioneer anomaly could be the first evidence that gravity deviates from an inverse square dependence," he told Popular Science last year. "It could be huge." ...

On the more mundane side of things, there was always the possibility that the culprit might just be heat. Specifically, heat from the plutonium inside the spacecrafts' generators, some of which got converted into electricity while the rest of it radiated into space. If it did so unevenly, radiating more heat in one direction than in another -- only a 5 percent difference is required -- that might be sufficient to give rise to the Pioneer anomaly. ...

Previous calculations have only estimated the effect of reflections. So Francisco and co used a computer modeling technique called Phong shading to work out exactly how the the emitted heat is reflected and in which direction it ends up traveling.

Phong shading was dreamt up in the 1970s and is now widely used in many rendering packages to model reflections in three dimensions. It was originally developed to handle the reflections of visible light from 3D objects but it works just as well for infrared light, say Francisco and co.

In particular, Phong shading has allowed the Portuguese team to include for the first time the effect of heat emitted from a part of the spacecraft called the main equipment compartment. It turns out that heat from the back wall of this compartment is reflected from the back of the spacecraft's antenna. Since the antenna points Sunward, towards Earth, reflections off its back would tend to decelerate the spacecraft. "The radiation from this wall will, in a first iteration, reflect off the antenna and add a contribution to the force in the direction of the sun."


via Mysterious Pioneer Anomaly May Finally Be Solved : Discovery News.

I was really hoping for some momentous variation in the force of gravity, but it seems that possibility with regard to the Pioneer data, has been vanquished.

Solar power without solar cells using hidden magnetic effect of light

A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers could lead to solar power without traditional semiconductor-based solar cells.

The researchers found a way to make an “optical battery,” said Stephen Rand, a professor in the departments of Electrical Engineering and Computer Science, Physics and Applied Physics.

In the process, they overturned a century-old tenet of physics.

“You could stare at the equations of motion all day and you will not see this possibility. We’ve all been taught that this doesn’t happen,” said Rand, an author of a paper on the work published in the Journal of Applied Physics. “It’s a very odd interaction. That’s why it’s been overlooked for more than 100 years.”

Light has electric and magnetic components. Until now, scientists thought the effects of the magnetic field were so weak that they could be ignored. What Rand and his colleagues found is that at the right intensity, when light is traveling through a material that does not conduct electricity, the light field can generate magnetic effects that are 100 million times stronger than previously expected. Under these circumstances, the magnetic effects develop strength equivalent to a strong electric effect.

“This could lead to a new kind of solar cell without semiconductors and without absorption to produce charge separation,” Rand said. “In solar cells, the light goes into a material, gets absorbed and creates heat. Here, we expect to have a very low heat load. Instead of the light being absorbed, energy is stored in the magnetic moment. Intense magnetization can be induced by intense light and then it is ultimately capable of providing a capacitive power source.”

What makes this possible is a previously undetected brand of “optical rectification,” says William Fisher, a doctoral student in applied physics. In traditional optical rectification, light’s electric field causes a charge separation, or a pulling apart of the positive and negative charges in a material. This sets up a voltage, similar to that in a battery. This electric effect had previously been detected only in crystalline materials that possessed a certain symmetry.

Rand and Fisher found that under the right circumstances and in other types of materials, the light’s magnetic field can also create optical rectification. ...

The light must be shone through a material that does not conduct electricity, such as glass. And it must be focused to an intensity of 10 million watts per square centimeter. Sunlight isn’t this intense on its own, but new materials are being sought that would work at lower intensities, Fisher said.

“In our most recent paper, we show that incoherent light like sunlight is theoretically almost as effective in producing charge separation as laser light is,” Fisher said.

This new technique could make solar power cheaper, the researchers say. They predict that with improved materials they could achieve 10 percent efficiency in converting solar power to useable energy. That’s equivalent to today’s commercial-grade solar cells.

“To manufacture modern solar cells, you have to do extensive semiconductor processing,” Fisher said. “All we would need are lenses to focus the light and a fiber to guide it. Glass works for both. It’s already made in bulk, and it doesn’t require as much processing. Transparent ceramics might be even better.”

In experiments this summer, the researchers will work on harnessing this power with laser light, and then with sunlight.

The paper is titled “Optically-induced charge separation and terahertz emission in unbiased dielectrics.” The university is pursuing patent protection ...

via Solar power without solar cells: A hidden magnetic effect of light could make it possible.

My first word was "light".  I was in a supermarket. I looked up and pointed to a light and said, "light". But what I was really thinking was, "Light is a time traveler. Light is the secret key."

The 'molecular octopus': A little brother of 'Schroedinger’s cat'

For the first time, the quantum behaviour of molecules consisting of more than 400 atoms was demonstrated by quantum physicists based at the University of Vienna in collaboration with chemists from Basel and Delaware. The international and interdisciplinary team of scientists has set a new record in the verification of the quantum properties of nanoparticles.

In addition, an important aspect of the famous thought experiment known as 'Schroedinger's cat' is probed. However, due to the particular shape of the chosen molecules the reported experiment could be more fittingly called 'molecular octopus'.

The researchers report their findings in Nature Communications.

Schroedinger's cat': simultaneously dead and alive?

Since the beginning of the 20th century, quantum mechanics has been a pillar of modern physics. Still, some of its predictions seem to disagree with our common sense and the observations in our everyday life. This contradiction was brought to the fore 80 years ago by the Austrian physicist Erwin Schroedinger; he wondered whether it was possible to realize states of extreme superposition such as, for example, that of a cat which is simultaneously dead and alive. This experiment has not been realized with actual cats for good reasons. Nevertheless, the successful experiments by Gerlich et al. show that it is possible to reproduce important aspects of this thought experiment with large organic molecules. ...

The use of specifically synthesized organic molecules consisting of complexes of up to 430 atoms enabled the researchers to demonstrate the quantum wave nature in mass and size regimes that hitherto had been experimentally inaccessible. These particles are comparable in size, mass and complexity to Insulin molecules and exhibit many features of classical objects. Nevertheless, in the current experiment the tailor-made molecules can exist in a superposition of clearly distinguishable positions and therefore -- similar to 'Schroedinger's cat' -- in a state that is excluded in classical physics.

via The 'molecular octopus': A little brother of 'Schroedinger’s cat'.

Parallel Worlds, Parallel Lives - Part I

Calculations with 14 Quantum Bits

Quantum physicists from the University of Innsbruck have set another world record: They have achieved controlled entanglement of 14 quantum bits (qubits) and, thus, realized the largest quantum register that has ever been produced. With this experiment the scientists have not only come closer to the realization of a quantum computer but they also show surprising results for the quantum mechanical phenomenon of entanglement.

The term entanglement was introduced by the Austrian Nobel laureate Erwin Schrödinger in 1935, and it describes a quantum mechanical phenomenon that while it can clearly be demonstrated experimentally, is not understood completely. Entangled particles cannot be defined as single particles with defined states but rather as a whole system. By entangling single quantum bits, a quantum computer will solve problems considerably faster than conventional computers. “It becomes even more difficult to understand entanglement when there are more than two particles involved,“ says Thomas Monz, junior scientist in the research group led by Rainer Blatt at the Institute for Experimental Physics at the University of Innsbruck. “And now our experiment with many particles provides us with new insights into this phenomenon,“ adds Blatt. ...

via Calculations with 14 Quantum Bits - Presseinformation der Universität Innsbruck.

Quantum physics explanation for smell gains traction

The theory that our sense of smell has its basis in quantum physics events is gaining traction, say researchers.

The idea remains controversial, but scientists reporting at the American Physical Society meeting in Dallas, US, are slowly unpicking how it could work.

The key, they say, is tiny packets of energy, or quanta, lost by electrons.

Experiments using tiny wires show that as electrons move on proteins within the nose, odour molecules could absorb these quanta and thereby be detected.

If the theory is right, by extending these studies, an "electronic nose" superior to any chemical sensor could be devised....

The means by which a detected molecule is translated into a smell within the brain has already been the subject of Nobel prize-winning research.

But how precisely an odorant molecule is detected remains a mystery.

As with the picture of molecular interactions that drives our understanding of enzymes and drugs, the very shape of odorant molecules has been assumed to be the way it is detected in the nose.

In this scenario, molecules are seen to be the "key" that fits neatly into a detector molecule in the nose that acts as a lock.

But in 1996, Luca Turin, now of the Massachusetts Institute of Technology in the US, suggested that the "vibrational modes" of an odorant were its signature.

Molecules can be viewed as a collection of atoms on springs, and energy of just the right frequency - a quantum - can cause the spring to vibrate.

Since different assemblages of molecules have different characteristic frequencies, Turin proposed, these vibrations could act as a molecular signature.

The idea has been debated in the scientific literature, but presentations at the American Physical Society meeting put the theory on firmer footing. ...

via BBC News - Quantum physics explanation for smell gains traction.

 

High-temperature Superconductor Spills Secret: A New Phase of Matter

The few high-temperature superconducting wires on the right conduct as much current as all the copper cables on the left. (Photo courtesy of American Superconductor.)

Scientists have found the strongest evidence yet that a puzzling gap in the electronic structures of some high-temperature superconductors could indicate a new phase of matter. Understanding this “pseudogap” has been a 20-year quest for researchers who are trying to control and improve these breakthrough materials, with the ultimate goal of finding superconductors that operate at room temperature. ...

Superconductors are materials that conduct electricity with 100 percent efficiency, losing nothing to resistance. Currently used in medical imaging, highly efficient electrical generators and maglev trains, they have the potential to become a truly transformative technology; energy applications would be just one beneficiary. This promise is hampered by one thing, though: they work only at extremely low temperatures. Although research over the past 25 years has developed “high-temperature superconductors” that work at warmer temperatures, even the warmest of them—the cuprates—must be chilled half-way to absolute zero before they will superconduct. ...

via March 24, 2011 - High-temperature Superconductor Spills Secret: A New Phase of Matter.

Time travel, God's particle and Higgs singlet: how messages might be sent to the past or future

Scientists believe they are one step closer to creating time travel.

American physicists from Vanderbilt University believe they may be able to use the Large Hadron Collider, the world's biggest atom smasher buried underground near Geneva, to send a type of matter called the Higgs singlet into the past.

But they're unsure if the Higgs singlet actually exists and whether the machine can produce it, according to a report by Live Science.

Advertisement: Story continues below

The Higgs singlet is related to another hypothesised particle called the Higgs boson, dubbed "God's particle" because it is associated with giving other particles mass, which the 27-kilometre long atom smasher may produce.

If the Higgs boson is created, the Higgs singlet may also appear, scientists say.

The Higgs singlet may be able to jump through space and time, travel through a hidden dimension, and then re-enter our dimension forwards or backwards in time, physicists Professor Thomas Weiler and graduate fellow Chui Man Ho believe.

"One of the attractive things about this approach to time travel is that it avoids all the big paradoxes," Professor Weiler said in a statement on research website arxiv.org.

"Because time travel is limited to these special particles, it is not possible for a man to travel back in time and murder one of his parents before he himself is born, for example.

"However, if scientists could control the production of Higgs singlets, they might be able to send messages to the past or future." ...

via Time travel, God's particle and Higgs singlet: how messages might be sent to the past or future.

Just listen. There is probably already a message from the future being sent back in Morse code.

".-.. .- .-. --. .   -.-. --- -- . -   .- .-.. . .-. -   --. . -   . ...- . .-. -.-- --- -. .   --- ..-. ..-.   - .... .   .--. .-.. .- -. . -   -... . ..-. --- .-. .   ..--- .---- ....- ----- "

Physicists move closer to efficient single-photon sources

Charles E. Blue - A team of physicists in the United Kingdom has taken a giant step toward realizing efficient single-photon sources, which are expected to enable much-coveted completely secure optical communications, also known as "quantum cryptography." The team presents its findings in Applied Physics Letters, a journal published by the American Institute of Physics.

Fluorescent "defect centers" in diamond act like atomic-scale light sources and are trapped in a transparent material that's large enough to be picked up manually. They don't need to be kept at super cold cryogenic temperatures or trapped in large electromagnetic fields to be stable—unlike quantum dots or trapped atoms.

This makes them strong contenders for use as sources of single photons (the quantum light particle) in provably secure quantum cryptography schemes, explains J. P. Hadden, a Ph.D. candidate in the Centre for Quantum Photonics, Department of Electrical and Electronic Engineering & H. H. Wills Physics Laboratory at the University of Bristol.

"Defect centers could also be used as building blocks for 'solid-state quantum computers,' which would use quantum effects to solve problems that are not efficiently solvable with current computer technology," Hadden says.

To fulfill the potential of diamond defect centers, it's essential that the light be collected efficiently from the diamond material. But this collection efficiency is dramatically reduced by reflection and refraction of light passing through the diamond-air interface.

"We managed to show an improvement in the brightness of these defect centers of up to ten times by etching hemispherical 'solid immersion lenses' into the diamond," notes Hadden. "This is an important result, showing how nanofabrication techniques can complement and enhance quantum technologies, and opens the door to diamond-defect-center-based implementations of quantum cryptography and quantum computation."

More recently, Hadden and colleagues developed a technique that allows them to reliably etch these structures over previously characterized defect centers to a precision of about 100 nanometers — another significant step toward a practical and repeatable combination of nanotechnology and quantum optics.

via Physicists move closer to efficient single-photon sources.

London 2012 countdown clock stops in Trafalgar Square

The digital clock in central London which has been counting down to the 2012 Olympics has stopped, less than 24 hours after it started.

The timer was unveiled in a ceremony in Trafalgar Square on Monday to mark the 500th day before next year's Games.

But the 6.5m (21ft) display became stuck on 500 days and 7:06:56.

"We are obviously very disappointed that the clock has suffered this technical issue," said a spokesman for the Swiss-based Swatch Group.

"The Omega London 2012 countdown clock was developed by our experts and fully tested ahead of the launch in Trafalgar Square," he added.

"We are currently looking into why this happened."

The clock had resumed its countdown by Tuesday evening.

via BBC News - London 2012 countdown clock stops in Trafalgar Square.

Probably just got caught in a time bubble created by the LHC. The Swiss are very advanced, but they probably shouldn't have used so many Higgs singlets to make this clock.  ;-)

Large Hadron Collider could be world’s first time machine

If the latest theory of Tom Weiler and Chui Man Ho is right, the Large Hadron Collider – the world’s largest atom smasher that started regular operation last year – could be the first machine capable of causing matter to travel backwards in time.

“Our theory is a long shot,” admitted Weiler, who is a physics professor at Vanderbilt University, “but it doesn’t violate any laws of physics or experimental constraints.”

One of the major goals of the collider is to find the elusive Higgs boson: the particle that physicists invoke to explain why particles like protons, neutrons and electrons have mass. If the collider succeeds in producing the Higgs boson, some scientists predict that it will create a second particle, called the Higgs singlet, at the same time.

According to Weiler and Ho’s theory, these singlets should have the ability to jump into an extra, fifth dimension where they can move either forward or backward in time and reappear in the future or past.

“One of the attractive things about this approach to time travel is that it avoids all the big paradoxes,” Weiler said. “Because time travel is limited to these special particles, it is not possible for a man to travel back in time and murder one of his parents before he himself is born, for example. However, if scientists could control the production of Higgs singlets, they might be able to send messages to the past or future.”

The test of the researchers’ theory will be whether the physicists monitoring the collider begin seeing Higgs singlet particles and their decay products spontaneously appearing. If they do, Weiler and Ho believe that they will have been produced by particles that travel back in time to appear before the collisions that produced them.

Weiler and Ho’s theory is based on M-theory, a “theory of everything.” A small cadre of theoretical physicists have developed M-theory to the point that it can accommodate the properties of all the known subatomic particles and forces, including gravity, but it requires 10 or 11 dimensions instead of our familiar four. This has led to the suggestion that our universe may be like a four-dimensional membrane or “brane” floating in a multi-dimensional space-time called the “bulk.”

According to this view, the basic building blocks of our universe are permanently stuck to the brane and so cannot travel in other dimensions. There are some exceptions, however. Some argue that gravity, for example, is weaker than other fundamental forces because it diffuses into other dimensions. Another possible exception is the proposed Higgs singlet, which responds to gravity but not to any of the other basic forces. ...



Illustration of singlet time travel theory. When a pair of protons collide in the Large Hadron Collider, the resultant explosion may create a special type of particle, called a Higgs singlet, that is capable of traveling forward and back in time. It would do so by leaving familiar three-dimensional space to travel in an extra dimension. (Jenni Ohnstad / Vanderbilt)

via Large Hadron Collider could be world’s first time machine | Research News @ Vanderbilt | Vanderbilt University.

 

How long does a tuning fork ring?

'Quantum-mechanics' solve a very classical problem:

From the wooden bars in a xylophone or the head of a drum, to the strings and sound box of a guitar or violin, musical instruments are the most familiar examples of mechanical resonators. The actual mechanical vibrations of these instruments create acoustic waves that we hear as sound. The purity of the emitted tone is intimately related to the decay of the vibration amplitude, that is, the mechanical losses of the system. A figure of merit for mechanical losses is the quality factor, simply called "Q", which describes the number of oscillations before the amplitude has decayed to a minute fraction of its starting value. The larger Q, the purer the tone and the longer the system will vibrate before the sound damps out.

In addition to the aesthetic examples found in a concert hall, mechanical resonators have become increasingly important for a wide variety of advanced technological applications, with such diverse uses as filtering elements in wireless communications systems, timing oscillators for commercial electronics, and cutting-edge research tools which include advanced biological sensors and emerging quantum electro- and optomechanical devices. Rather than producing pleasing acoustics, these applications rely on very "pure" vibrations for isolating a desired signal or for monitoring minute frequency shifts in order to probe external stimuli.

For many of these applications it is necessary to minimize the mechanical loss. However, it had previously remained a challenge to make numerical predictions of the attainable Q for even relatively straightforward geometries. Researchers from Vienna and Munich have now overcome this hurdle by developing a finite-element-based numerical solver that is capable of predicting the design-limited damping of almost arbitrary mechanical resonators. "We calculate how elementary mechanical excitations, or phonons, radiate from the mechanical resonator into the supports of the device", says Garrett Cole, Senior Researcher in the Aspelmeyer group at the University of Vienna. "This represents a significant breakthrough in the design of such devices."

The idea goes back to a previous work by Ignacio Wilson-Rae, physicist at the Technische Universitaet Muenchen. In collaboration with the Vienna group the team managed to come up with a numerical solution to compute this radiation in a simple manner that works on any standard PC. The predictive power of the numerical Q-solver removes the guesswork that is currently involved (e.g., trial and error prototype fabrication) in the design of resonant mechanical structures. The researchers point out that their "Q-solver" is scale independent and thus can be applied to a wide range of scenarios, from nanoscale devices all the way up to macroscopic systems.

via How long does a tuning fork ring?.

Probing atomic chicken wire

Under the scanning tunneling microscope, graphene reveals its honeycomb structure made up of rings of carbon atom, visible as small hexagons. The larger hexagons result from an interference process occurring between the graphene and the underlying boron nitride.

Daniel Stolte

Graphene – a sheet of carbon atoms linked in a hexagonal, chicken wire structure – holds great promise for microelectronics. Only one atom thick and highly conductive, graphene may one day replace conventional silicon microchips, making devices smaller, faster and more energy-efficient.

In addition to potential applications in integrated circuits, solar cells, miniaturized bio devices and gas molecule sensors, the material has attracted the attention of physicists for its unique properties in conducting electricity on an atomic level.

Otherwise known as pencil "lead," graphene has very little resistance and allows electrons to behave as massless particles like photons, or light particles, while traveling through the hexagonal grid at very high speeds.

The study of the physical properties and potential applications of graphene, however, has suffered from a lack of suitable carrier materials that can support a flat graphene layer while not interfering with its electrical properties.

Researchers in the University of Arizona's physics department along with collaborators from the Massachusetts Institute of Technology and the National Materials Science Institute in Japan have now taken an important step forward toward overcoming those obstacles.

They found that by placing the graphene layer on a material almost identical in structure, instead of the commonly used silicon oxide found in microchips, they could significantly improve its electronic properties.

Substituting silicon wafers with boron nitride, a graphene-like structure consisting of boron and nitrogen atoms in place of the carbon atoms, the group was the first to measure the topography and electrical properties of the resulting smooth graphene layer with atomic resolution.

The results are published in the advance online publication of Nature Materials.

"Structurally, boron nitride is basically the same as graphene, but electronically, it's completely different," said Brian LeRoy, an assistant professor of physics and senior author of the study. "Graphene is a conductor, boron nitride is an insulator."

"We want our graphene to sit on something insulating, because we are interested in studying the properties of the graphene alone. For example, if you want to measure its resistance, and you put it on metal, you're just going to measure the resistance of the metal because it's going to conduct better than the graphene."

Unlike silicon, which is traditionally used in electronics applications, graphene is a single sheet of atoms, making it a promising candidate in the quest for ever smaller electronic devices. Think going from a paperback to a credit card.

"It's as small as you can shrink it down," LeRoy said. "It's a single layer, you'll never get half a layer or something like that. You could say graphene is the ultimate in making it small, yet it 's still a good conductor." ...

via Probing atomic chicken wire.