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"Everything should be as simple as it is, but not simpler", Albert Einstein
Browsing All Posts published on »August, 2011«
Teaching Radioactivity: Ions produced by radiation carry a current
This demonstartes that a radioactive source produces radiation that will ionise the air. The conducting air completes a circuit to charge an electroscope. Use the circuit to show the ionising effect of the radiation and present it as a means of detecting ionising radiation.
The Star That Should Not Exist
August 31, 2011
A team of European astronomers has used ESO’s Very Large Telescope (VLT) to track down a star in the Milky Way that many thought was impossible. They discovered that this star is composed almost entirely of hydrogen and helium, with only remarkably small amounts of other chemical elements in it. This intriguing composition places it […]
Chaotic Spiral Galaxies
August 31, 2011
George Contopoulos, Mirella Harsoula Abstract: We study the role of asymptotic curves in supporting the spiral structure of a N-body model simulating a barred spiral galaxy. Chaotic orbits with initial conditions on the unstable asymptotic curves of the main unstable periodic orbits follow the shape of the periodic orbits for an initial interval of time and […]
The dialogue between quantum light and matter
August 31, 2011
The Rabi model (RM) describes the simplest interaction between light and matter. In its semiclassical form, this model describes the coupling of a two-level system and a classical monochromatic field. The fully quantum model considers the same situation, with the light field quantized. Although this model has had an impressive impact on many fields of […]
Firing laser beams into the sky could make it rain, say scientists
August 30, 2011
Water droplets have been created by shooting lasers into the air. The technique might be used to create or prevent rain Ever since ancient farmers called on the gods to send rain to save their harvests, humans have longed to have the weather at their command. That dream has now received a boost after researchers used a […]
Interview with Lucio Mayer on world’s first realistic simulation of the formation of Milky Way
August 30, 2011
First glimpse into birth of the Milky Way – For almost 20 years astrophysicists have been trying to recreate the formation of spiral galaxies such as our Milky Way realistically. Now astrophysicists from the University of Zurich present the world’s first realistic simulation of the formation of our home galaxy together with astronomers from the […]
Step Up to the Barred Spiral Galaxy
August 30, 2011
The Canada-France-Hawaii Telescope in Hawaii sees the barred spiral galaxy NGC 2903 almost face-on in this photograph. The central bulge glows yellow with older stars, while the spiral arms contain younger stars as determined by their blue color, and star formation regions of red. http://www.space.com/34-image-day.html
How To Make Viagra
August 30, 2011
By Enrico Uva Wizards exist in real life, beyond the films and books of Harry Potter. They cook willow bark extract in car battery acid and wood alcohol and convert it into a pleasant-smelling component of candy or of a rubbing compound. In their glassware, petroleum products turn into life-saving medicines. The vastly underrated wizards […]
Observation of the Thermal Casimir Force is Open to Question
August 30, 2011
We discuss theoretical predictions for the thermal Casimir force and compare them with available experimental data. Special attention is paid to the recent claim of the observation of that effect, as predicted by the Drude model approach. We show that this claim is in contradiction with a number of experiments reported so far. We suggest […]
ERIS: World’s first realistic simulation of the formation of the Milky Way
August 30, 2011
— After nine months of number-crunching on a powerful supercomputer, a beautiful spiral galaxy matching our own Milky Way emerged from a computer simulation of the physics involved in galaxy formation and evolution. The simulation by researchers at the University of California, Santa Cruz, and the Institute for Theoretical Physics in Zurich solves a longstanding […]
Gordon Kane On SUSY At The LHC
August 29, 2011
Despite the hopes of most and the preconceptions of many, news from the Lepton-Photon conference in Mumbay, India, report that the Standard Model is as alive and strong as it has ever been. Indeed, the recent searches for Supersymmetry by ATLAS and CMS, now analyzing datasets that by all standards must be considered “a heck […]
Two-in-one: The dazzling Pac-Man Nebula powered by an open cluster of stars
August 29, 2011
This incredible cosmic image shows a nebula with an open cluster of stars inside it. Described by Nasa as ‘a busy workshop of star formation’, NGC 281 is better known as the Pac-Man Nebula due to its distinctive shape. It is powered by IC 1590, the open star cluster at its very centre. Τhese young […]
Magnetic joystick
August 29, 2011
Regulating Brownian Fluctuations with Tunable Microscopic Magnetic Traps A. Chen, G. Vieira, T. Henighan, M. Howdyshell, J. A. North, A. J. Hauser, F. Y. Yang, M. G. Poirier, C. Jayaprakash, and R. Sooryakumar Phys. Rev. Lett. 107, 087206 (Published August 18, 2011) Magnetic particles can be guided with external fields through small-scale fluidic environments, bringing […]
Life in the Universe by Stephen Hawking
August 28, 2011
In this talk, I would like to speculate a little, on the development of life in the universe, and in particular, the development of intelligent life. I shall take this to include the human race, even though much of its behaviour through out history, has been pretty stupid, and not calculated to aid the survival […]
Space Station Sees Hurricane Irene
August 27, 2011
Cameras mounted on the International Space Station captured new views of Hurricane Irene at 4:27 p.m. EDT on August 26, 2011 as the storm bore down on the east coast of the United States. Accompanied by narration from Expedition 28 Flight Engineer Mike Fossum of NASA, the video showed the massive system moving north at […]
Milky Way stars born from intergalactic gas
August 27, 2011
Astronomers using the Hubble Space Telescope may have solved the mystery of how the Milky Way continues to spawn new stars at a consistent rate despite its diminishing gas reserves. They say the galaxy is being supplied by clouds of gas originating from outside of the Milky Way, and that these findings could help refine […]
British atomic clock ‘most accurate in world’
August 27, 2011
The machine, which is responsible for keeping Britain’s clocks on track and also contributes to the international measure of time, is accurate to within two 10 million billionths of a second. It is one of a handful of similar clocks which determine the exact length of a second by measuring microwaves as they cause reactions […]
Gas clouds may have created biggest cosmic explosions
August 27, 2011
THEY would make supernovae look like firecrackers. Giant gas clouds in the early universe could have powered the most energetic eruptions since the big bang. Evidence for supermassive black holes – weighing millions or billions of suns – has been found in the early universe, but no one knows how they grew so big so […]
LHC results put supersymmetry theory ‘on the spot’
August 27, 2011
By Pallab Ghosh Results from the Large Hadron Collider (LHC) have all but killed the simplest version of an enticing theory of sub-atomic physics. Researchers failed to find evidence of so-called “supersymmetric” particles, which many physicists had hoped would plug holes in the current theory. Theorists working in the field have told BBC News that […]
Extraterrestrial dust reveals asteroid’s past and future
August 26, 2011
Talk about seeing a world in a grain of sand. A sprinkling of asteroid dust that slipped into Japan’s Hayabusa probe when it touched down on the asteroid Itokawa six years ago has revealed surprising details about the space rock’s past and its likely future. Hayabusa was meant to land on the 500-metre-wide asteroid in […]
The Plot Of The Week – Heavy Particle Production In ATLAS
August 25, 2011
If you work in experimental high-energy physics you soon acquire a particular sensitivity to the economical display of relevant information. Producing figures that convey the most meaning with the minimum effort is sort of an art, and it is a necessary consequence that HEP experimentalists -the smart ones- end up converging on the definition of […]
Experiments Show Gravity Is Not an Emergent Phenomenon
August 24, 2011
The way gravity effects quantum particles proves that it cannot be an emergent phenomenon, says physicist. One of the most exciting ideas in modern physics is that gravity is not a traditional force, like electromagnetic or nuclear forces. Instead, it is an emergent phenomenon that merely looks like a traditional force. This approach has been […]
Did Einstein discover E = mc2?
August 24, 2011
Who discovered that E = mc2? It’s not as easy a question as you might think. Scientists ranging from James Clerk Maxwell and Max von Laue to a string of now-obscure early 20th-century physicists have been proposed as the true discovers of the mass–energy equivalence now popularly credited to Einstein’s theory of special relativity. These […]
Astronomers Find Ice and Possibly Methane On Snow White, a Distant Dwarf Planet
August 23, 2011
Astronomers at the California Institute of Technology (Caltech) have discovered that the dwarf planet 2007 OR10 — nicknamed Snow White — is an icy world, with about half its surface covered in water ice that once flowed from ancient, slush-spewing volcanoes. The new findings also suggest that the red-tinged dwarf planet may be covered in […]
Evidence for Mars floods all dried up?
August 23, 2011
Lava, not water, may have carved the biggest channels on Mars. Ever since NASA’s Mariner 9 spacecraft beamed back the first images of the channels in the 1970s, most people have assumed they were created by massive floods. But David Leverington of Texas Tech University in Lubbock says flowing water would have left behind much more sediment […]
New ATLAS Limits On Higgs Mass
August 22, 2011
By Tommaso Dorigo Much awaited, the results of searches for the Higgs boson at the Large Hadron Collider have been released by the ATLAS collaboration, and are being shown at the Lepton-Photon conference in Mumbay, India. I will provide here just the main results, with little commentary – I wish to let the cake cool down […]
Galaxies Are Running out of Gas: Why the Lights Are Going out in the Universe
August 22, 2011
A CSIRO study has shown why the lights are going out in the Universe. The Universe forms fewer stars than it used to, and a CSIRO study has now shown why: the galaxies are running out of gas. Dr Robert Braun (CSIRO Astronomy and Space Science) and his colleagues used CSIRO’s Mopra radio telescope near […]
A pendulum of horror
August 22, 2011
In 1842, the first American author of tales of horror, Edgar Allen Poe (1809-1849) wrote a short story entitled, The Pit and the Pendulum. Poe’s stories often contained a strong element of terror, in part, because he left many of the details quite vague, just as a standard technique of psychological terror is to keep […]
Higgs boson signals fade at Large Hadron Collider
August 22, 2011
Cern scientist says he sees ‘no striking evidence of anything that could resemble a discovery’ in hunt for Higgs boson Ripples of excitement swept through the physics community last month when Cern scientists reported what looked like glimpses of the long-sought Higgs boson. But the hopes have been dashed as it was revealed that the tantalising hints had all but […]
New Fossils Show Sulfur-Based Microbes Lived on Earth 3.4 Billion Years Ago
August 21, 2011
…Presenting a New Target for Astrobiology Clusters of islands poked through hot oceans 3.4 billion years ago, when the world still had no oxygen and the seas churned under a pallid, overcast sky. But life thrived on Earth even then, scientists say — and now they have the world’s oldest fossils to prove it. There […]
Black holes and pulsars could reveal extra dimensions
August 21, 2011
We discuss the observable effects of enhanced black hole mass loss in a black hole-neutron star (BH-NS) binary, due to the presence of a warped extra spatial dimension of curvature radius L in the braneworld scenario. For some masses and orbital parameters in the expected ranges the binary components would outspiral—the opposite of the behavior due to […]
Gravitational Lensing as a Mechanism For Effective Cloaking
August 20, 2011
Benjamin K. Tippett In light of the surge in popularity of electromagnetic cloaking devices, we consider whether it is possible to use general relativity to cloak a volume of spacetime through gravitational lensing. A metric for such a spacetime geometry is presented, and its geometric and physical implications are explained. In general relativity, there is […]
Pioneer Anomaly is Fading
August 20, 2011
The Pioneer anomaly is a tiny, unexplained deceleration of the Pioneer 10 and 11 spacecraft, which are now at the edge of the Solar System. A 19 August report inPhysical Review Letters describes an arduous, multi-year effort to accurately define the anomaly by gathering and analyzing all available tracking data for the two probes. The analysis shows […]
Samuel A. Goudsmit Papers available online
August 20, 2011
The Niels Bohr Library and Archives is pleased to announce that it has digitized the complete Samuel A. Goudsmit Papers (1921–1979, 30 linear feet, approximately 67,000 images). The Goudsmit Papers are a major international collection of correspondence, research notebooks, reports, World War II science documents, and other material of Goudsmit, a Dutch physicist who spent most of […]
Dark Energy, Dark Matter, Dark Force: Not Afraid Of The Dark
August 19, 2011
Sascha Vongehr The public repulsion against dark matter and dark energy is really annoying. Rob Knop at scientopia compares it to 17th century catholic church mentality; Ethan picks it up and bangs the dark matter explains everything drum although dark matter does not fit very well to galaxy rotation curves – Modified Newtonian Dynamics (MOND) fits much better: (From: Begeman, Broeils, […]
Could Earth’s ring of antimatter power spacecraft?
August 19, 2011
A belt of antimatter has been discovered circling the Earth, which in future could be used to fuel voyages that race at breakneck speeds to other planets in the Solar System. Antimatter has properties that are opposite those of normal matter – for example the positive charge on a proton is negative in an antiproton. […]
What role does the third law of thermodynamics play in Szilard engines?
August 19, 2011
The role of the third law of thermodynamics in the Szilard engine has been addressed. If the ground state is non-degenerate, the entropy production defined as the work extractable from the engine divided by temperature vanishes as temperature approaches zero due to the third law. The degenerate ground state induced by the symmetry or by […]
Shannon entropy as a measure of uncertainty in positions and momenta
August 19, 2011
This paper is prepared as a contribution to the proceedings after the 12th ICSSUR/Feynfest Conference held in Foz do Iguacu (Brazil) from 2 to 6 May 2011. In the first part I briefy report the topic of entropic uncertainty relations for position and momentum variables. Then I investigate the discrete Shannon entropies related to the […]
STEREO Tracks Solar Storms From Sun To Earth
August 19, 2011
NASA’s STEREO spacecraft and new data processing techniques have succeeded in tracking space weather events from their origin in the sun’s corona to impact with the Earth, resolving a 40-year mystery about the structure of the structures that cause space weather: how the structures that impact the Earth relate to the corresponding structures in the […]
Aliens may destroy humanity to protect other civilisations…..
August 19, 2011
….say scientists Rising greenhouse emissions may tip off aliens that we are a rapidly expanding threat, warns a report for Nasa It may not rank as the most compelling reason to curb greenhouse gases, but reducing our emissions might just save humanity from a pre-emptive alien attack, scientists claim. Watching from afar, extraterrestrial beings might […]
China Reveals Solar Sail Plan To Prevent Apophis Hitting Earth in 2036
August 18, 2011
A small shove could prevent a global catastrophe, according to Chinese plans Apophis is a 46 million tonne asteroid that will pass within a hair’s breath of Earth in 2029. However, Apophis’s trajectory is likely to take it through a region of space near Earth known as a keyhole that will ensure the asteroid returns […]
Candles shine new light on diamonds
August 18, 2011
By Christine Lavelle Candle flames contain millions of tiny diamond particles, a university professor has discovered. Research by Wuzong Zhou, a professor of chemistry at the University of St Andrews in Fife, revealed that around 1.5 million diamond nanoparticles are created in a candle flame every second it is burning. Dr Zhou used a new […]
Time-Energy Uncertainty Relation for a Quantum Clock as a Control Device
August 18, 2011
A quantum clock working as a control device is examined. The quality of the control process is characterized by the magnitude of deviation of perturbed state from unperturbed state of the controlled system. Uncertainty relations that relate the time duration of the process and energy of the clock to the quality of the control are […]
Mysterious Blob in the Ancient Universe Explained
August 17, 2011
Giant Space Blob Glows from Within VLT finds primordial cloud of hydrogen to be centrally powered Observations from ESO’s Very Large Telescope have shed light on the power source of a rare vast cloud of glowing gas in the early Universe. The observations show for the first time that this giant “Lyman-alpha blob” — one […]
Fukushima Radiation In California
August 17, 2011
We all remember the earthquake and ensuing tsunami that hit Japan (see figure 1) and caused major troubles in the Fukushima nuclear power plant, which was severely damaged. Problems with containing radiation followed, leading to the pumping of huge amounts of seawater into the reactor, in an attempt to cool it down. The question on […]
How unitary cosmology generalizes thermodynamics and solves the inflationary entropy problem
August 17, 2011
We analyze cosmology assuming unitary quantum mechanics, using a tripartite partition into system, observer and environment degrees of freedom. This generalizes the second law of thermodynamics to “The system’s entropy can’t decrease unless it interacts with the observer, and it can’t increase unless it interacts with the environment.” We show that because of the long-range […]
The Heisenberg Uncertainty Principle and the Nyquist-Shannon Sampling Theorem
August 17, 2011
The derivation of the Heisenberg Uncertainty Principle (HUP) from the Uncertainty Theorem of Fourier Transform theory demonstrates that the HUP arises from the dependency of momentum on wave number that exists at the quantum level. It also establishes that the HUP is purely a relationship between the effective widths of Fourier transform pairs of variables […]
On the genesis and evolution of Integrated Quantum Optics
August 17, 2011
Applications of Integrated Optics to quantum sources, detectors, interfaces, memories and linear optical quantum computing are described in this review. By their inherent compactness, efficiencies, and interconnectability, many of the demonstrated individual devices can clearly serve as building blocks for more complex quantum systems, that could also profit from the incorporation of other guided wave […]
Status of the UC-Berkeley SETI Efforts
August 17, 2011
We summarize radio and optical SETI programs based at the University of California, Berkeley. The SEVENDIP optical pulse search looks for ns time scale pulses at visible wavelengths using an automated 30 inch telescope. The ongoing SERENDIP V.v sky survey searches for radio signals at the 300 meter Arecibo Observatory. The currently installed configuration supports […]
August 31, 2011
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