Faster than light; a dream of Mankind ever since Einstein's Theory of Special Relativity. According to Einstein, light can only move at a certain rate in a vacuum roughly 186,000 miles per second and nothing with mass can accelerate to the speed of light. As a mass approaches lightspeed it takes an ever increasing amount of energy to continue that acceleration (actually, the body itself gains mass as it increases speed) and it would take an infinite amount of energy to make a mass reach the speed of light (and the object being so accelerated would collapse into a black hole if it were to happen). Lightspeed is an absolute speed limit; nothing can go beyond lightspeed.
But that's not really true; if a body were already moving faster than light it could continue to do so, and in fact it would take energy to slow down to lightspeed. FTL is like a mirror of our universe, a place where velocity is infinite and lightspeed is as slow as it gets. A turtle in such a superluminal universe would be the fastest creature imaginable. It has been theorized that there are ftl particles called Tachyons that exist, but they have never been found. How could they be? At their rate of movement they would not be detectable by us slow pokes.
Recently a team of researchers (the OPERA team) published a paper in which they concluded that neutrinos, those ephemeral particles (sometimes called ghost particles) that form during certain nuclear reactions, move faster than light. According to the abstract:
"The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km with much higher accuracy than previous studies conducted with accelerator neutrinos. The measurement is based on high-statistics data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS timing system and of the OPERA detector, as well as a high precision geodesy campaign for the measurement of the neutrino baseline, allowed reaching comparable systematic and statistical accuracies. An early arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of light in vacuum of (60.7 \pm 6.9 (stat.) \pm 7.4 (sys.)) ns was measured. This anomaly corresponds to a relative difference of the muon neutrino velocity with respect to the speed of light (v-c)/c = (2.48 \pm 0.28 (stat.) \pm 0.30 (sys.)) \times 10-5. "
Now the immediate assumption by both the researchers and others is that this is a case of instrumentation error. In fact, the researchers ask for replication of their work. Read here.
(Thanks, Dana Mathewson)
Prior efforts to measure the speed of neutrinos has suggested a speed slightly greater than light, and this confirms these efforts. But, these a difficult measurements to make, and the margin for error is wide.
What the Oscillation Project with Emulsion-tRacking Apparatus (OPERA) project did was utilize Cerns's Neutrinos to Gran Sasso (CNGS) at the proton sychotron, which consists of a high-intensity and high-energy beam of muon neutrinos generated by the particle accelerator and beamed it at another site some 450 miles away. Muon neutrinos are one of three "flavors" of neutrinos (the other two being electron and tau.) The interesting thing about neutrinos is that they can "oscillate" between the three flavors while in motion, changing into the other type. And of the three known varieties each has an antiparticle with reversed spin. It is possible that the antiparticles are simple the particles that for some reason reverse their spin. Neutrinos do not have an electrical charge.
And, as a result, they pass through almost everything. Detection is difficult - but not impossible. Methods employed have used heavy water surrounded by phototubes which will show Cherenkov radiation, or large volumes of chlorine checked regularly for argon or germanium, a byproduct of interaction with neutrinos. There are other methods, but none are especially sensitive.
In the OPERA experiment detectors were used to study the three millisecond trip of neutrinos generated at CERN. The experimenters (who were interested in neutrino oscillation) used photographic emulsion plates with lead interspersed between. There were 1300 tons of bricks in the gadget, or 150,000 bricks of these plates. There is a wikipedia entry explaining details of the experiment. http://en.wikipedia.org/wiki/OPERA_experiment
The experiment yielded measurements that suggested the neutrinos arrived by a factor of 1 in 40,000 prior to when they should have arrived at lightspeed, suggesting they are moving faster than light. This falls within the margin of experimental error, so the researchers published their findings.
These results contradict studies of the SN 1987A supernova event; the neutrino flux would have arrived on Earth several years before they did. There is some agreement with prior attempts to measure neutrino speed.
Now neutrinos are believed to have a very small mass; they were thought originally to be massless. This makes the idea of their traveling faster than light even more bizarre; how do they get boosted beyond lightspeed? Remember, they are coming from us Tardyons, us slow movers. If they were at that speed as Tachyons it would make sense. But how does an object with mass accelerate beyond lightspeed?
A couple of years ago an experiment in reversing a beam of light (not just reflecting it, but actually reversing it) came up with some startling FTL results; the beam retrod it's path faster than light.
But this does not violate Relativity; INFORMATION isn't moving faster than light, merely a beam that is retracing it's path.
One wonders what we would see if a particle, say a neutron, were to go into the fiber optic tube along with that light beam; it would appear to an outside observer that the particle was actually an antiparticle because everything would be reversed. If it appears to be moving backward, is it really moving backward in time?
Many commenters on message threads about this have pointed out that a number of quantum effects suggest faster than light incidences. Quantum entanglement, for example. Quantum entanglement occurs when a particle and another particle have direct interaction and develop congruous quantum states. If the two resulting particles go off in different directions the particles continue to have the same aspects i.e. energy states, spin, etc. If one of the particles changes state the other does as well - instantaneously, no matter how far away it is from it's twin. For instance, if an observer measures the energy state of one particle he collapses the wavefront (as they say) and the particle has that particular energy state - but so does it's twin. There seems to be some strange sort of communication between the particles that defy rationality - and that seems to defy the lightspeed barrier.
But do they? Is it, perhaps, not we that are moving and not the particles? In point of fact, there may well not be two particles at all, but one seen from different aspects. One wonders; if the Universe splits at every event then perhaps quantum entanglement may be a view into that split universe i.e. both particles are one and the same but moving in a different direction. Perhaps in the resulting alternate reality the observer is with the other particle and sees ours as the one moving away? This sort of thinking is quick to deliver headaches, and illustrates how our understanding of the Universe is sketchy, indeed!
But enough idle speculation. Suffice it to say that quantum entanglement does not transmit information in the classic sense, and so there is no true ftl present.
But what of these neutrinos? Are they moving ftl or not?
Hard to say at this point. If they are we are at the cusp of a revolution in science.
Einstein has been well proven, and he is not to be overturned lightly. That is why it is important for the experiment to be repeated, and for hard criticisms to be made; it has to stand the rigorous testing that Relativity, quantum physics, etc. have already undergone.
Which makes Dana Mathewson's point pertinent:
"This is how science is "done" in the real world -- as opposed to in the Church of Climate Change. Scientists at CERN have detected neutrinos traveling faster than the speed of light. http://www.urgentagenda.com/PERMALINKS%20VI/SEPTEMBER%202011/23.SCIENCE.HTML
So what do they do? They take the (scientifically correct) approach that until they (and others) can reproduce the phenomenon, they will assume that they have made a mistake, either in their experiment or in their observation of the results.
This is the way that science is conducted among adults."
And right he is! Science is about rigorous testing, about observation of reality, about experimentation and careful work. It is not about consensus, or about maybe, or about computer programs that do not match reality. This is science; Global Warming is cargo cult science.
So, will the future hold hyperdrives for spacecraft, or Star-Trekkian warp drives? Even if this is true and there are things that travel faster than light, we are a long, long, long way from figuring out a way to manipulate such things. It may even be theoretically possible to travel ftl, but not be practical. Imagine a weight, for instance that is heavy enough to be too much for one or two men but not too much for six. But imagine if that object was too small for six men to crowd around to lift it; it becomes impossible to lift it manually, even though the parameters are not so unusual. (I stole this analogy from Isaac Asimov from his novel Prelude to Foundation where the lead character - Hari Seldon - explains why his theory that it could be possible to use mathematics to predict the future may never work.) There are other FTL ideas as well; wormholes move you between points a and b without going through the intervening space, for instance, or it may be possible to make a "warp drive" using something nicknamed the Alcubierre drive after the scientist who proposed it; using, say, artificial gravity, you could bend space-time in such a way that a bubble of spacetime moves along the fabric of the universe itself. Lightspeed remains normal inside and outside the bubble, but the bubble can move far faster than light. There are many fanciful ideas, but none of them are even close to being theoretically possible, much less practical.
And even approaching lightspeed is well beyond any capabilities we are remotely in possession of; the best two options for high speed spaceflight involves the Buzzard Ramjet, a fusion rocket that uses interstellar hydrogen as fuel. Theoretically a ramscoop could get close to lightspeed. In practice, it doesn't work for a whole host of reasons; there is too much drag from a magnetic scoop (perhaps some superior attractive field would work?), the interstellar medium isn't ionized adequately outside of the solar wind anyway, and we don't know how to make controlled fusion work. We would have to fuse protons if we could. As I said, some new tech could take care of some of these problems, but how many of them? Oh, and those protons would be coming on at near lightspeed relative to the ship, appearing as gamma rays and sterilizing everything on board. And should the ship hit so much as a grain of sand BOOM!
There are other types of interstellar drives that may barely suffice; light sails augmented by terrestrial-based lasers, say, or really, really, really big Orion drives. (The Orion was invented in the 1950's for a Mars mission. It uses a railgun to fire atomic bombs under a pusher plate. One bomb per second can build up quite a bit of velocity over time. For interstellar distances you would need like A MILLION bombs; you would reach a tenth of lightspeed and then coast. It would take about 150 years to reach the Centari stars; we had better develop suspended animation first.)
We will not be going to the stars any time soon; we need to make the best of the solar system that the Almighty has kindly provided for us. There are 9 - er - 8 - er- somewhere between the two planets revolving around the sun (as far as we know; there may be another dark one out there we haven't seen), innumerable moons and moonlets, asteroids, Kuiper Belt Objects, etc. We have plenty of worlds to conquer right here. Many of them can be settled. Prime candidates are, in my mind, the Moon, Mars, Ganymede and Callisto, Titan. In the farther future we may do Mercury and Europa, Triton and Pluto. We can settle asteroids as we like. We can also build space colonies, enormous habitats like beer cans or bicycle wheels that rotate for gravity. There really is an awful lot for us waiting out there.
But as for this new discovery; it is exciting and may or may not be valid. We really do live in fascinating times; the first humans to learn a great deal of this. Later generations will be far less fortunate because they will be reading about it second hand and it seems unlikely that the pace of technological development will continue this swiftly; eventually the curve will slow. This is a golden age, much like the classical Greek period, and they come rarely.
So let's enjoy it while we can.