Photons detected without damage iStock/THINKSTOCK Measuring the properties of photons usually involves absorbing them, but a new device detects their passage and lets them fly by. One of the cornerstones of quantum theory is the principle that you cannot measure any property of an object without affecting the object itself. Indeed, detecting the very existence of a photon until now has usually meant destroying it. The conventional way to detect a single particle of light is to catch it with a sensor, absorbing its energy but destroying the particle in the process. In recent years, physicists have developed methods to extract part of the information from a particle’s quantum state — for example showing that it is more likely to be in one place than in another — in a set of methods known as weak measurement. This could be useful in applications such as quantum networks, which promise to transport data with unbreakable encryption, but require delicate quantum states to be transmitted without any disturbance.
Ask A Physicist: Why Believe In Dark Matter? So far in the comments, I keep seeing the same note- which works out roughly to "oh, you mean they REALLY can't see it? Oh, well then it must be a conceptual kludge or fudge factor, because that doesn't make sense." So I'll be a little more emphatic. We KNOW dark matter exists- that is to say, a decent fraction of the universe's mass is in particles with very limited participation in the electromagnetic force- because we SEE what that mass does to everything else we can see- as surely as you could postulate a foot from a set of footprint without having the sawed-off foot in your hands. That's because we really do have its footprints- on essentially everything we see in the sky and proceed to model. That still leaves dark matter as one of the two biggest fish in both cosmology and particle physics with tons of open questions- is it made of supersymmetric particles, which are their own antiparticles, and we could detect them by the flashes of gamma rays they release as they die?
Inflationary Universe data in question, but cheer up, there are cures for aging - On Science Blogs Hello there! If you enjoy the content on On Science Blogs, consider subscribing for future posts via email or RSS feed. Has BICEP2 lost its muscle? Data claiming support for the inflationary theory of the Universe’s beginnings were released at a much ballyhooed press conference in March. When I wrote about the announcement here at the time, I said I was surprised at the wholehearted embrace of a report that was so clearly contingent, tentative, preliminary. The claims were based on observations of cosmic microwave background radiation left over from the Big Bang, observations made by the BICEP2 telescope at the South Pole. We should know fairly soon, within the next year or two, whether what BICEP2 saw was the real thing. The Dustup Beginning last week, however, what physicist Sean Carroll called “Arrrgh Rumors” have been asking whether the BICEP2 results would come to literal dust. On May 15, Carroll tweeted “Could the BICEP2 signal be dust, not CMB? Young blood reverses aging
Distant artificial atoms cooperate by sharing light, physicists show An international team of scientists has shown for the first time that atoms can work collectively rather than independently of each other to share light. Quantum physicists have long discussed such an effect, but it has not been seen before in an experiment. The team included scientists from ETH Zürich (a leading university in Switzerland) who performed the experiment and theoretical scientists from the Université de Sherbrooke in Québec and the University of Calgary in Alberta. The researchers showed the sharing of light or "photon-mediated interaction" between artificial atoms confined to a one-dimensional quantum system. Their paper, "Photon-mediated interactions between distant artificial atoms," is published this week in the top-ranked journal Science. The two artificial atoms "showed a coherent exchange interaction, something not seen before for distant quantum systems in an open environment," says lead author Arjan van Loo, a PhD student in the Quantum Device Lab at ETH Zürich.
Ultracold big bang experiment successfully simulates evolution of early universe Physicists have reproduced a pattern resembling the cosmic microwave background radiation in a laboratory simulation of the big bang, using ultracold cesium atoms in a vacuum chamber at the University of Chicago. "This is the first time an experiment like this has simulated the evolution of structure in the early universe," said Cheng Chin, professor in physics. Chin and his associates reported their feat in the Aug. 1 edition of Science Express, and it will appear soon in the print edition of Science. Chin pursued the project with lead author Chen-Lung Hung, PhD'11, now at the California Institute of Technology, and Victor Gurarie of the University of Colorado, Boulder. The cosmic microwave background is the echo of the big bang. It turns out that under certain conditions, a cloud of atoms chilled to a billionth of a degree above absolute zero (-459.67 degrees Fahrenheit) in a vacuum chamber displays phenomena similar to those that unfolded following the big bang, Hung said.
Quantum Equations Suggest Big Bang Never Happened Two physicists are trying to revive one of the great debates of twentieth-century science, arguing that the Big Bang may never have happened. Their work presents a radically different vision of the universe from the one cosmologists now work with. The term Big Bang was created by astrophysicist Fred Hoyle as a way to mock the theory. Nevertheless, the problem of what, if anything, came before the Big Bang has continued to trouble many scientists, along with questions about how it actually occurred. "The Big Bang singularity is the most serious problem of general relativity because the laws of physics appear to break down there," says Dr. Ali and Das are keen to point out that they were not seeking a preordained outcome, or trying to adjust their equations to remove the need for the Big Bang. The quest to unite the two great theories of modern physics into quantum gravity has been one of the major projects of some of science's greatest minds in recent decades.
Astronomers reveal contents of mysterious black hole jets An international team of astronomers has answered a long standing question about the enigmatic jets emitted by black holes, in research published today in prestigious journal Nature. Jets are narrow beams of matter spat out at high speed from near a central object, like a black hole. "Although they have been observed for decades, we're still not sure what they are made of, or what powers them," ESO astronomer Dr María Díaz Trigo, lead author of the study, said. The team studied the radio waves and X-rays emitted by a small black hole a few times the mass of the Sun. However, a few weeks later, the team took another look and this time saw radio emissions corresponding to the sudden appearance of these jets, and even more interestingly, lines had appeared in the X-ray spectrum – the tell-tale signature of ordinary atoms – around the black hole. Dr Miller-Jones said this is the first strong evidence of such particles in jets from a typical small black hole.
Gravitational Waves: A Black Hole’s Fury - From Quarks to Quasars Jacques Cousteau once said, “What is a scientist after all? It is a curious man looking through a keyhole, the keyhole of nature, trying to know what’s going on.” The scientists working at the Laser Interferometer Gravitational-Wave Observatory (LIGO) have a similar attitude when it comes to the quest for gravitational waves. This unusual theoretical phenomenon was originally predicted by Einstein in the same 1916 paper that gave us Einstein’s theory of general relativity. Currently, gravitational waves are the only untainted mechanism we can use to study the moment of the Big Bang and the inflationary period of our universe. A gravitational wave is a ripple in the fabric of spacetime. Gravitational waves, though weaker than its electromagnetic counterpart, have the advantage that they can pass through other matter without being significantly affected. Image Credit MASA What’s the catch? Image: NASA/ESA Joshua Filmer
Take a Psychedelic Trip through a World of Morphing Fractals by Alexandre Lehmann No, you’re not on drugs, or maybe you are, in which case you might want to wait a while before watching this. Overstepping Artifacts is the latest fractalized music video from French animator and musician Alexandre Lehmann (aka Ricardo Montalban or Zzzzra) as part of his ongoing Musicians with Guns series. The clip is the definition of ‘otherworldly,’ and was created using special fractal software that results in morphing forms that seem part organic and part architectural. Overstepping Artifacts is a follow-up to his 2011 video Astroblast which is similar in tone but visual quite different and also worth a watch. Lehmann talks a bit about his process in a 2012 interview over on Empty Kingdom.
Accidental Discovery Dramatically Improves Electrical Conductivity - First Posted: Nov 17, 2013 11:43 AM EST Accidental discovery dramatically improves electrical conductivity Credit:Didier Descouens Quite by accident, Washington State University researchers have achieved a 400-fold increase in the electrical conductivity of a crystal simply by exposing it to light. The effect, which lasted for days after the light was turned off, could dramatically improve the performance of devices like computer chips. WSU doctoral student Marianne Tarun chanced upon the discovery when she noticed that the conductivity of some strontium titanate shot up after it was left out one day. At first, she and her fellow researchers thought the sample was contaminated, but a series of experiments showed the effect was from light. Like Us on Facebook "It came by accident," said Tarun. And while other researchers have created persistent photoconductivity in other materials, this is the most dramatic display of the phenomenon.
Unprecedented neutrino discovery is a "Nobel Prize in the making" Uh, I'm probably not the right one to answer this, but I'll try. You should most likely check out the related article though. Or better, this thread by casen and look at Corpore Metals reply. Yes, they were found moving through the earth, or at least can. HI Ronny, Neutrinos are so small that they can pass right through your body or the Earth or whatever, without actually touching anything, like electrons, protons etc. That helps a lot. Wow, thanks!