Showing posts with label quantum. Show all posts
Showing posts with label quantum. Show all posts

Saturday, June 16, 2012

Neutrinos, Still Not Faster Than Light, For Reals This Time

FirstNeutrinoEventAnnotated
The first use of a hydrogen bubble chamber to detect neutrinos, on November 13, 1970. VIA: Wikimedia commons
Even people with no other interest in or knowledge of physics what so ever, are familiar with the concept that nothing can travel faster than light. This "cosmic speed limit" as it is often called, is based on Einstein's theory of special relativity, which, after now having stood up to over 100 years of experimentation, is one of the most tested, and well established facts in all of physics. So it's understandable why, when CERN published the results of an experiment late last year which seemed to show the sub atomic particle known as the neutrino might actually be capable of traveling faster than light, it was kind of a big deal.

The results in question were first published in September of 2011, after an experiment in which beams of neutrinos repeatedly fired (1500 times to be exact) from an accelerator in Geneva, managed to reach their destination in Italy a full 60 nanoseconds faster than should have been physically possible.

Not surprisingly, these results were met with skepticism  from the vast majority of physicists, who presumed they were likely due to an experimental error of some form, and would almost certainly not stand up to further analysis. Which wasn't a particularly surprising stance for them to take, given that actually confirming it to be possible for anything to violate the physical limits set by special relativity- yes, even by as little as 60 nanoseconds (60 billionths of a second)- would literally have redefined one of the fundamental rules of our reality as we now understand it. And sure enough, in February of this year an initial examination of the equipment used in the experiments, found that a combination of a faulty fiber optic connection and GPS unit, were most likely responsible for the result.

On June 8th, at the International Conference on Neutrino Physics and Astrophysics in Kyoto, CERN research director Sergio Bertolucci announced that the results of four new experiments designed to test the original findings. All of which, after correcting for the apparent timing errors in the original experiment, recorded a time of flight for their neutrinos that was under that of the speed of light. Thus making it official: Like every other known bit of matter in the universe, neutrinos, STILL can't travel faster than light.

-CAINE- 

VIA: Wired Science

Sunday, May 27, 2012

Higgs Boson And The Research Surrounding it Explained, in Cartoon Form



Via: phdcomics on:Vimeo

While we're on the subject of quantum physics, and sense this video is all about two of my favorite things; cause I'm the kind of guy that picks complex scientific disciplines and theoretical particles as his favorite things. Let's talk about the Higgs boson. Well, let's have someone who might actually have the required knowledge to talk about particle physics and the research surrounding the search for this theoretical bit of matter, talk about  it- in the form of a cartoon. Cause I believe, no matter how old you are, there isn't anything you can't learn by watching cartoons.

In all seriousness. I've written about the Higgs and particle physics in general, several times before. But the Higgs Boson, and the quantum world in which it exists, is without question, such a complex subject, that it's always worth revisiting. 

-CAINE-

Source: Camels with Hammers -VIA: Left Hemispheres

Chinese Researchers Set New Distance Record For "Teleporting" Qubits


One of the most astonishing and confusing properties of the quantum world is the phenomena of quantum entanglement. Through this effect, it's possible for two individual particles to become linked to one another and act as single system, regardless of the distance between them.

Say, for instance, you managed to entangle a couple of particles, A and B. Even if particle A were residing quietly inside an accelerator here on Earth, while particle B was busy floating along through space on the other side of the galaxy, this entangled pair would still act as a single system. If one were to then try and observe particle A - thus causing a shift in it's quantum state through the mere act of observation, and the joy of  the uncertainty principal, quantum superposition, and all that - particle B, would instantaneously adopt the same quantum state.

Now, I'm not going to pretend to understand exactly how quantum entanglement manages to happen in the first place, or how scientists manage to deliberately produce the effect for experimentation, because, I don't- in my defense, neither does anyone else. But the phenomena of quantum entanglement is one that's been known to, and studied by, quantum physicists, for quite some time. And while it's easy to imagine a whole host of spectacular Sci-fi applications for the effect (some of which might also become a reality someday), currently, one of the most promising, real world application for entanglement, is in the field of data transfer, processing, and communications.

Enter, the Qubit. Which is the quantum analog to the the digital bit.

Now then, if I've done a fair job of explaining the concept of entanglement to you, you'll understand why the word teleporting appears in quotation marks in the title of this entry. Because when a group of scientists from China recently managed to set a new record for quantum "teleportation" by successfully transferring information between 1100 photons, across 97 km of free-space, they didn't actually teleport anything. Rather, they managed to successfully entangle and effect one group of particles, by manipulating another, across a previously unachievable distance. In other words, they were able to transfer data (qubits), from one place to another, without actually transferring anything at all. Which is kind of what makes Quantum entanglement such an attractive means of communication and data transfer in the first place. Since there's literally nothing to intercept, eaves dropping on this form of quantum communication,  would be nearly impossible. I say nearly, because, I can easily imagine some clever person finding a way to entangle a set of particles of their own, in order to intercept transmissions. But that too is just my own bit of speculative science fiction, at this point.

One of the (many) current problems and limitations of this particular method of quantum transfer, and why this groups achievement is a significant one - aside from just being cool as hell- is that entangling particles is understandably difficult. So the entanglements currently being created, are easily broken and interfered with. Which is why the previous record for such a transfer, which was also set by a group from China, in 2010, was just 16 km,.Which still seems an impressive feat, by my standards. But if the results of experiments like these can be reproduced, and the entanglements themselves can be made more stable. I think communications through quantum "telepotation", might actually be a reality, someday. Though certainly not anytime soon.

As for actual the actual teleportation of complex matter, which is what we all think of when we read the word... Sorry, but I still don't see it happening.

But that's a discussion for a different day.

-CAINE-

VIA: Wired Science -And- phys.org