Researchers in Germany produced element 112 in 1996, and now that it has been recognized by the International Union for Pure and Applied Chemistry, it will be the newest addition to the periodic table of the elements. It’s currently known as ununbium, Latin for ‘one-one-two,’ but it will be given an official name before it’s added to the chart.
The new element is one of only 22 elements that are man-made, and it’s 277 times heavier than hydrogen, making it the weightiest element on the periodic table. To make it, scientists at Germany’s Centre for Heavy Ion Research fused the the nuclei of zinc and lead. The atomic number 112 refers to the sum of the atomic numbers of zinc, which has 30, and lead, which has 82. Atomic numbers denote how many protons are found in the atom’s nucleus [Reuters]. Creating new elements isn’t just a why-not-do-it challenge: It has also helped researchers to understand how nuclear power plants and atomic bombs function [Reuters].
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In the realm of quantum mechanics, atoms and subatomic particles just don’t follow the rules that we’re governed by in the larger world of classical mechanics. For example, the theory of quantum mechanics predicts that two or more particles can become “entangled” so that even after they are separated in space, when an action is performed on one particle, the other particle responds immediately. Scientists still don’t know how the particles send these instantaneous messages to each other, but somehow, once they are entwined, they retain a fundamental connection [LiveScience].
Now, a new study has dragged entanglement a little bit closer to our classical world. Researchers managed to entangle two pairs of vibrating ions so that when the motion of one pair of ions was changed, the other pair reflected the change as well. Previously, researchers have entangled particles in much more esoteric ways, coordinating the spin of electrons or the polarization of photons. With this study, says coauthor John Jost, “We’ve entangled something that has never been entangled before, and it’s the kind of physical, oscillating system you see in the classical world, just much smaller” [LiveScience].
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Three recent studies raised hopes that physicists had caught the first glimpses of dark matter, but the somewhat contradictory results guarantee that researchers will be puzzling over the issue for some time to come. The latest results come from NASA’s orbiting Fermi Gamma-ray Space Telescope, which was launched last June. The evidence is a reported excess of high-energy electrons and their antimatter counterparts, positrons, which could be created as dark matter particles annihilate or decay [Nature News].
Peter Michelson, principal investigator for the instrument on Fermi that made the detection, cautions that his group is not yet claiming to have found a smoking gun for dark matter. The signal could also come from more mundane sources nearby, such as pulsars, the spinning remnants of supernovae. “But if it isn’t pulsars, it is some new physics,” says Michelson [Nature News]. The new findings are published in Physical Review Letters. Meanwhile, a satellite named PAMELA recently detected higher than expected numbers of positrons, which seems to corroborate the Fermi findings. But results from a balloon experiment conducted high over Antarctica last year add a dash of confusion to the mix.
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By tracing radioactive pollution created by the nuclear tests of the 1950s, researchers have settled the question of whether the human heart creates new cells during a person’s lifespan. “The dogma has always been that cell division in the heart pretty much stops after birth…. In medical school, we teach that you’ll die with the heart cells you’re born with” [Science News], comments cardiovascular expert Charles Murry. However, a new study has overturned this dogma, and found that the heart does regenerate, albeit slowly.
Cell turnover rates can easily be measured in animals by making their cells radioactive and seeing how fast they are replaced. Such an experiment, called pulse-labeling, could not ethically be done in people. But Dr. Frisen realized several years ago that nuclear weapons tested in the atmosphere until 1963 had in fact labeled the cells of the entire world’s population [The New York Times]. The Cold War tests produced a radioactive form of carbon called carbon-14, which was absorbed by plants and worked its way up the food chain; in humans, carbon-14 gets into the DNA of new cells and remains unchanged for the cells’ lives.
Once nuclear tests ended in 1963, levels of carbon-14 began to gradually decline. Because the level of carbon-14 in the atmosphere falls each year, the amount of carbon-14 in the DNA can serve to indicate the cell’s birth date [The New York Times], says lead researcher Jonas Frisén. His team found that people’s hearts have cells that are younger than the people themselves, indicating that new cells have grown since birth. Heart experts say it’s a remarkable use of the nuclear tests’ impacts. “I am very excited about how they have used this novel technology to get something useful out of such a terrible environmental disaster” [Technology Review], says Murry.
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The mysterious stuff known as dark matter may have left a calling card at the edge of the Earth’s atmosphere where a space-faring satellite named PAMELA could pick it up. Researchers are reporting that PAMELA detected a high number of the subatomic particles called positrons, the positively-charged counterpoints to electrons, which could have been created by collisions between dark matter particles. “PAMELA found a number of positrons much higher than expected,” the mission’s principal investigator Piergiorgio Picozza [said]. “Many think this could be a signal from dark matter” [SPACE.com]. But of course, others think there’s a more mundane explanation.
Dark matter is one of the greatest enigmas in astrophysics: It cannot be observed directly, so researchers have to study its effects on normal matter to try to deduce what it’s made of. The top candidates for dark matter, the heavy but invisible stuff that makes up 23 percent of the universe, are weakly-interacting massive particles. Contrary to their WIMPy name, when two of these particles collide, they annihilate each other in a burst of energy and propel a cloud of matter and antimatter particles into space. The theory has been a favorite of physicists for years, but until now, no one had detected evidence of these collisions [Wired].
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Cold fusion is the dream that won’t die for some nuclear physicists. If they could replicate the nuclear reaction that powers our sun under room temperature conditions, the thinking goes, humanity would gain a clean source of nearly limitless energy. Work on cold fusion has been relegated to the margins of science since a much-hyped experiment 20 years ago was discredited, but now a new team of researchers says they’ve conducted experiments that should reinstate the field. “We have compelling evidence that fusion reactions are occurring” at room temperature [EE Times], said lead researcher Pamela Mosier-Boss, of the Space and Naval Warfare Systems Center in San Diego.
On March 23, 1989, physicists Stanley Pons and Martin Fleischmann claimed to have created fusion reactions in a tabletop experiment, at room temperature. [Watch a video of the annoucement here.] Their claims of producing small amounts of excess heat — energy — in their experiments were at first met with excitement, then skepticism and finally derision as other scientists were unable to reproduce the results [Houston Chronicle]. Most physicists eventually concluded that the extra energy was either a fluke or the product of an experimental error.
Mosier-Boss announced her team’s new findings at a meeting of the American Chemical Society yesterday, twenty years to the day since the earlier declaration. She has also published the work in the journal Naturwissenschaft.
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French physicist Bernard d’Espagnat has won the annual Templeton Prize with its purse of $1.4 million; the prize is often given to scientists who find common ground between religion and science. Professor d’Espagnat, 87, worked with great luminaries of quantum physics but went on to address the philosophical questions that the field poses [BBC News].
Physicists may be more open to seeing a higher power behind the great mysteries of the universe than scientists in other disciplines: Including Dr. d’Espagnat, five of the past 10 Templeton winners have been physicists or have had strong connections to the discipline [The Christian Science Monitor].
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Particle physicists have ruled out one of the possible remaining hiding places of the Higgs boson, bringing them one step closer to finding the slippery subatomic particle–or, conceivably, to ruling out its existence.
Physicists believe that the Higgs particle interacts with some other particles, like the W and Z bosons, to give them mass. The standard quip about the Higgs is that it is the “God Particle” — it is everywhere but remains frustratingly elusive. Confirming the Higgs would fill a huge gap in the so-called Standard Model, the theory that summarizes our present knowledge of particles [AFP].
The new results, from the Tevatron particle accelerator at the Fermi National Accelerator Laboratory, narrow down the range of masses where the Higgs boson may be found. Physicist Craig Blocker explains that particle accelerators smash particles together and then sift through the debris produced, looking for particles with certain masses. Previous collider experiments had placed a lower bound of 114 giga-electron volts (GeV), a measure that can be used for particle mass, on the Higgs, and theoretical calculations require it to be less than 185 GeV. The new Fermilab results, from its Tevatron collider, rule out a Higgs mass between 160 and 170 GeV…. “If the Higgs had a mass in this fairly narrow range” of 160 to 170 GeV, he says, “we should have seen it, we had a good chance to see it” [Scientific American].
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After all the excitement and anticipation surrounding the Large Hadron Collider’s launch last September, its first few months have been an anticlimactic cascade of disappointments. When a fault shut down the subatomic particle collider just nine days after the first beam of protons whizzed around its 17-mile track, officials at first said it would take several weeks to repair. Then they revised that estimate, saying it wouldn’t be fixed until spring of 2009–and then that changed to summer of 2009. Now, officials say that repairs won’t be finished before September, at the earliest.
To appease impatient high-energy physicists, the laboratory will probably run the machine (albeit at reduced powers) for a ten-month stretch from November until the autumn of 2010 [Nature News]. Officials at CERN, the European agency that runs the collider, hadn’t planned to run it through the winters when electricity costs are higher; they estimate that this appeasement will cost them an extra $10.5 million for electricity.
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Researchers have accomplished teleportation, though not of the “Beam me up, Scotty” variety. Instead, they sent information between two individual atoms of the element ytterbium, which were suspended in separate containers three feet apart. Because the quantum information instantly hops from one atom to the other without ever crossing the space between the two, scientists call the transfer “teleportation” [Science News].
Over the years, teleportation experiments have demonstrated that quantum states - for example, the spin of a particle or the polarization of a photon - can be teleported using a variety of methods. But the researchers behind the latest experiment … claim that this is the first time information has been teleported between two separate atoms in unconnected enclosures [MSNBC]. Researchers say that atoms are a better bet than photons for storing quantum information because they’re easier to hold on to, and say that their system could one day be harnessed for spy-proof communication using quantum cryptography, or for powerful quantum computers.
The befuddling process of quantum teleportation is made possible by the what Einstein called the “spooky” properties of quantum materials. Until it’s measured, an atom or photon can remain in an ambiguous state of all possible values simultaneously. Whenever a particle is measured, though, this range of possibilities “collapses” into a single, distinct value. The original, uncommitted state is lost, and it’s this ability to hold multiple values at once that gives [quantum materials] such potential for high-performance computing [Science News].
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By harnessing a quantum mechanic force of repulsion researchers have caused nanoparticles to repel each other, and in their next experiment they plan to levitate a tiny gold nanosphere. The quantum force is part of the Casimir effect, first predicted in 1948 by the Dutch physicist Hendrik Casimir, which describes both the attraction and repulsion that occur between two tiny objects held close together in a vacuum. While the attractive force has previously been demonstrated, the new experiment marks the first time the repulsive force has been seen in a lab.
But the experiment wasn’t just a neat physics trick; the researchers say the repulsive force may one day be used in nanoscale devices. Lead author Jeremy Munday says the research may lend itself to producing ultrasensitive detectors and almost friction-free devices by separating their components via Casimir repulsion. “Where you would normally have friction,” he says, “you can start to greatly reduce that by having a repulsive interaction that doesn’t let the surfaces come into contact” [Scientific American].
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As the year 2008 draws to a close, the world’s timekeepers are giving us a little extra time to wrap up loose ends: They’re giving us one extra second, to be precise. The “leap second” must be added to keep atomic clocks ticking along in time to the planet’s rotation. So at precisely 23:59:60 at Greenwich, England, on New Year’s Eve, there will be a one-second void before the onset of midnight and the start of the New Year…. By the time the transition from 2008 to 2009 arrives in North America the Leap Second will have already been inserted into the world’s timescale [SPACE.com].
The adjustment is necessary because we have two different ways of measuring time. Traditionally, humankind has reckoned time by the spin of the Earth and its orbit around the sun. Under this astronomical arrangement, a second is one-86,400th of our planet’s daily rotation. But because of tidal friction and other natural phenomena, that rotation is slowing down by about two-thousandths of a second a day. Since the 1950s, however, atomic clocks — which are based on the unwavering motions of cesium atoms — have made it possible to measure time far more accurately, to within a billionth of a second a day [The New York Times]. To keep the two measurement systems in alignment, the atomic clocks have to add an extra second about every 500 days.
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The standard model of physics got it right when it predicted where the mass of ordinary matter comes from, according to a massive new computational effort. Particle physics explains that the bulk of atoms is made up of protons and neutrons, which are themselves composed of smaller particles known as quarks, which in turn are bound by gluons. The odd thing is this: the mass of gluons is zero and the mass of quarks [accounts for] only five percent. Where, therefore, is the missing 95 percent? [AFP]
The answer, according to theory, is that the energy from the interactions between quarks and gluons accounts for the excess mass (because as Einstein’s famous E=mc² equation proved, energy and mass are equivalent). Gluons are the carriers of the strong nuclear force that binds three quarks together to form one proton or neutron; these gluons are constantly popping into existence and disappearing again. The energy of these vacuum fluctuations has to be included in the total mass of the proton and neutron [New Scientist]. The new study finally crunched the numbers on how much energy is created in these fluctuations and confirmed the theory, but it took a supercomputer over a year to do so.
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An enormous helium balloon floating about 24 miles above Antarctica has detected a mix of high-energy electrons so exotic that researchers say the particles must have been created by some fascinating process: They may have been formed when dark matter particles collided and annihilated each other, or else a surprisingly close astronomical object like a pulsar could be spitting the electrons at Earth.
Researchers can’t yet determine which answer is correct, but say the dark matter explanation is more exciting. Dark matter is one of astrophysics’ greatest enigmas. It is thought to be five times more common than visible matter, but there is no proof of what it is made of. The existence of dark matter has largely been inferred from its gravitational effects, such as the fact that most galaxies have enough mass to remain as well-defined objects despite having too little visible matter to account for the necessary gravity [National Geographic News]. If the research balloon did detect the signature of dark matter through the particles left over from collisions, it would be the closest researchers have ever gotten to seeing the mysterious stuff.
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Fixing the glitches that shut down the Large Hadron Collider (LHC) in September will apparently be no easy task: A spokesman for the particle physics lab CERN has announced that the repairs will cost $21 million and will probably not be completed until late June. Cern spokesman James Gillies said: “If we can do it sooner, all well and good. But I think we can do it realistically (in) early summer” [BBC News].
The startup of the LHC on September 10th may win an award for anticlimax of the year: Physicists talked for months about the mysteries of physics that the particle collider would reveal, while nervous laypeople worried that when engineers flipped the switch on the machine it would create a miniature black hole that could destroy the earth. But instead of either of these scenarios coming true, the LHC broke within two weeks before getting a chance to perform any experiments.
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