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Albert Einstein's Theory of Relativity states that no object in the universe can travel faster than the speed of light in the vacuum.  (Source: AP)

CERN's headquarters in Geneva, Switzerland gleams in the night.  (Source: AP/Anja Niedringhaus)

The OPERA experiment shoots a neutrino beam from Switzerland to Italy. As neutrinos only interact with matter via the weak force and gravitational attractions, they can pass right through the ground.  (Source: OPERA/CERN)

The final destination of the beam is the OPERA detector in Italy.  (Source: OPERA/CERN)
Neutrinos are first ever observed example of faster-than-light travel in a non-medium, defy laws of physics

Einstein's Theory of Relativity was unequivocal -- the fastest objects in the universe could move was the speed of light in a vacuum, which works out to around 299,792,458 meters per second (approximately 7e8 miles an hour).  To travel faster than the speed of light would allow fast travel to other worlds and even the possibility of travelling back in time.  But Einstein's 1905 theory was firm -- objects cannot travel faster than the speed of light.

I. The Erosion of Relativity?

Over the last several decades, exceptions to the Theory of Relativity have cropped up in experiments.  For example physicists have discovered that photons can pass through certain mediums at a faster than light pace 
via quantum tunneling, and another study revealed pulses of sound can also outpace photons in a medium.

Now, for the first time, subatomic particles have been witnessed as travelling faster than the speed of light.  
CERN, the European physics organization known for maintaining the Large Hadron Collider, has been playing with neutrinos in its OPERA experiment.  As they don't interact with normal particles it's been sending them through the Earth, hurtling from CERN in Geneva, Switzerland to INFN Gran Sasso Laboratory in Italy.  The journey is 454-miles (730-kilometers) long.

But the CERN researchers noticed something intriguing.  The neutrino traversed the distance 60±10 nanoseconds faster than light would have according to advanced analysis using GPS systems and atomic clocks to measure the time it took the roughly 15,000 neutrinos produced to complete their journey.  Those results indicate that the neutrinos were travelling two-parts-per-million faster than the speed of light.

CERN has published 
the results [press release] and presented a live webcast late last week on the discovery.

Robert Plunkett of the 
Fermilab laboratory in Batavia, Ill. in an interview with LiveScience states, "The consequences [of faster than light travel] would be absolutely revolutionary and very profound. That's why such a claim should be treated very carefully and validated as many ways as you can."

"According to relativity, it takes an infinite amount of energy to make anything go faster than light. If these things are going faster than light, then these rules would have to be rewritten."

Michael Peskin, a theoretical physicist at SLAC National Accelerator Laboratory in Menlo Park, Calif., concurs, adding, "It's really thought to be an absolute speed limit. Quantum field theory, the mathematical theory on which basically all results in particle physics are based, has the property that signals cannot travel faster than the speed of light through a vacuum. It’s really an absolute prohibition."

II. Physics Gets More Complicated

Absolute prohibition?  Maybe not.  The rules of physics seem on the verge of getting a bit weirder.  After all, to the best knowledge of most physics professionals, the CERN results look accurate.  But they seem in direct contradiction to the Japanese Kamiokande II experiment, which measured neutrinos emitted from a Large Magellanic Cloud supernova SN1987A, which sits 168,000 light years from Earth.  Measurements from that exploded star indicate that neutrinos travel within 1 part per 100,000,000 of the speed of light.

That's drastically different than the new results -- 2,000 times different, to be precise.  But both results could prove correct.  
Derek Fox of Pennsylvania State University suggests that a quirk of string theory or other advanced physics theory could reconcile the measurements.

CERN isn't shying away from criticism.  It is publishing all its data in hopes that other theoretical physicists will help to verify it -- or disprove the stunning conclusion.

One indication the results may be correct, though, comes from Fermilab, a physics lab located just outside Batavia, Illinois.  In its 
MINOS experiment, Femilab researchers have been sending neutrinos in a similar experiment to a detector at the bottom of the Soudan mine in Minnesota.

In 2007 they also seemed to observe faster-than-light travel of neutrinos, but unfortunately their lesser experimental equipment made it impossible to determine whether the measurement was legitimate or merely an artifact of the high level of statistical deviation in the measurements.

Professor Plunkett, who also serves as co-spokesperson for the MINOS experiment, is excited to find out if the results were authentic.  He states, "There was something that could have been a fluctuation in the direction of things arriving early, but it didn't have enough significance for us to make such a claim. Obviously, the hunt is on and we'll be upgrading that previous measurement and also implementing something we already had in the works, which is a plan to make improvements so we can reduce our errors. One of our next objectives is going to be trying to verify or disprove this result as hard as we can."

III. Just How Weird is Physics?

One thing that's important to bear in mind is that while this appears to be macroscopic and substantial violation of the Theory of Relativity, it only applies in a special scenario.  By and large most objects in the universe still appear to be behaving as expected.

In other words, basic physics education is unlikely to change much or get much harder based on all these radical discoveries.  However, for graduate researchers in the field of physics, they better prepare themselves to deal with a lot more weird.

The possibility of harnessing faster than light travel would seemingly be wealth worth the headache, though.  Many researchers are 
already dreaming up faster than light spaceship engines.  With such engines the vast time it would take to travel to the stars could be drastically reduced.

Some quick background for the physics layperson, a neutrino is somewhat akin to an uncharged electron, though it can come in several flavors -- electron neutrinos, muon neutrinos and tau neutrinos.  Neutrinos are typically produced in nuclear reactions (including those inside stars) and when high-energy cosmic rays collide with matter.

Neutrinos are hardly rare -- 6.5e10 (65 billion) pass through every square centimeter perpendicular to the direction of the Sun in the region of the Earth each second, 
courtesy of solar generation.  For that reason, researchers typically emit their neutrinos in a direction roughly perpendicular to the solar neutrons, so they can be easily distinguished and rely on careful calibration to filter out remaining inaccuracies in the detector.

Like other particles, as per the Symmetry Theory, neutrinos have an antiparticle, known as antineutrinos.  However, some believe that antineutrinos and neutrinos are actually the same particle type (it's hard to determine as they lack distinguishing charge).  If this is true, it would make neutrinos/antineutrinos the only known (fermion) example of a "Majorna" particle -- a particle that is it's own antiparticle.

If neutrinos and antineutrinos are not identical, it should be interesting going ahead to see if antineutrinos -- produced from nuclear decay and fission, among other things -- can also travel faster than light.  One might expect this to be the case, given that they only interact with matter gravitationally and through the weak force, as with neutrinos.



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RE: how about...
By amarcord on 9/26/2011 10:58:15 AM , Rating: 5
1) Neutrinos have a mass > 0, even though really small (< 10e-68 g)

Even if they hadn't any mass, they could let you send information through time

2) The difference in speed is greater than the statistical error

3) The same way you can distinguish the light of the sun from the light of your Display.


RE: how about...
By amarcord on 9/26/2011 11:02:57 AM , Rating: 2
Anyhow the article contains a mistake:

A majorana particle is a fermion which coincides with its own antiparticle.

Non fermion example are very common in the nature, like photons.


RE: how about...
By joex444 on 9/27/2011 5:19:29 AM , Rating: 2
I'd like to add we've never observed a Majorana fermion. (And it capitalized, as it was a person's name.)


RE: how about...
By Nelson Lam on 9/26/2011 11:31:47 AM , Rating: 1
How can the CERN scientists prove that the one particle created on one side was the one detected later on the other side? Just like if I throw a ball to a distant target and you caculate the speed of ball by measuring the distance in between me and the target, and measuring the time between the ball left my hand and the target was hit by a ball without assuring the ball hitting the target was exactly the one I threw out, then it could be wrongly concluded that I could throw out a ball with a speed faster than speed of light.


RE: how about...
By MozeeToby on 9/26/2011 11:51:37 AM , Rating: 5
They aren't dealing with individual particles, rather a beam of particles. Imagine you have a fire hose and you want to find out how fast the water from the hose travels across a room. You turn on the water for 1 second, and time how long it takes the water to get there. It doesn't matter that the first drop of water isn't the first one that left the hose.

You could even do it in the middle of a rainstorm (which is equivalent to what they did since we are always getting bombarded with neutrinos from the sun). Graph how much water is hitting the far wall, then apply some statistics to figure out when the water from the hose started getting there.

It won't be perfect but if you repeat the experiment a few thousand time (Remember, they had 3 years worth of data), you'll eventually be able to say with certainty the speed of the water, or at the very least put lower bound on the speed which is what we really care about in this case. The lower bound that the found was ever so slightly faster than c.


RE: how about...
By GulWestfale on 9/26/2011 5:29:22 PM , Rating: 5
this is the second time this year that CERN has violated the principles of causality. the first time will happen in november.

"i'm sorry, we don't serve neutrinos who are faster than light here," says the barkeeper. a neutrino walks into a bar.

now stop it with the lame neutrino jokes! i already heard them next week.


RE: how about...
By Nelson Lam on 9/26/2011 9:17:20 PM , Rating: 2
What I meant was that imagine, if the neutrinos sent out from the transmitter cause creation of other neutrinos or similar particles at a distance closer to the detector and those new particles were the one hitting the detector, and therefore it appeared that the original neutrinos had travelled faster than the light of speed.


RE: how about...
By MarkHark on 10/2/2011 7:27:31 AM , Rating: 2
Even in the case you propose, for the secondary neutrinos to be created closer to the target than the primary ones, a signal would have to travel at faster-than-light speeds from
the primary neutrinos to wherever the secondary ones should appear.


RE: how about...
By Nelson Lam on 10/10/2011 11:35:15 AM , Rating: 2
So, it could be some kind of signal that travelled faster than the speed of light and not the particle itself. It could be something without a mass and beyond what we think we understand.


RE: how about...
By ekv on 9/27/2011 2:58:09 AM , Rating: 3
Still leaves some room for doubt. Interesting nonetheless.

If the "beam of particles" were modulated or perhaps even pulsed that would lend more certainty that indeed those are the correct particles to be timed. Though with a beam then I have questions about wave-fronts and so on.

Are all neutrinos faster than light? or perhaps only these CERN neutrinos? What makes them go faster/slower?


RE: how about...
By montanagf on 9/27/2011 12:32:49 PM , Rating: 2
n the question of certainty that the particles that hit the target are the ones tranamitted. i'm not aphysicist, but as iunderstand quantum physics, there can be causality at a distance, as opposed to the pool ball causality of newetonian physics. Would that complicate the question?


RE: how about...
By montanagf on 9/27/2011 1:00:18 PM , Rating: 3
would make the calculations moot.
possible that the neutrinos measured as going through the earth, never left the sun?

IS RELATIVITY RELEVANT IN QUANTUM PHYSICS?


RE: how about...
By Mitch101 on 9/26/2011 11:42:30 AM , Rating: 2
How incredible and far ahead was Einstein that this was 100 years ago in what seems like the dark ages of technology that he drew up such theories. He lived into the 50's but his theory on light dates back 100 years.

And why does it seem like there has not been anyone as grand/celebrated since? I cant imagine what he could do conceive with today's technology.

Ive read this article on other sites can someone explain why they believe Neutrinos allow for sending information back in time as I read it its just faster than light.


RE: how about...
By MozeeToby on 9/26/2011 12:02:33 PM , Rating: 4
Any effect that allows a piece of information to reach it's destination faster than light automatically breaks causality (aka allows information to be sent back in time). It doesn't matter how it is accomplished, all that matters is that information can get somewhere faster than light from the event that produced the message.

In very simple terms, we know empirically that something traveling close to the speed of light experiences time dilation. What people don't think about is what that really means: people will disagree about when an event happened based on how fast they are going. If you have to space ships about to have an epic battle but traveling away from each other at near light speed, you can have disagreement over who shot first based on where the observer is and how fast they are traveling. So long as everything stays below the speed of light, it doesn't matter who shot first, the math always works out so that the same ship will win the fight no matter where you're observing from.

As soon as you allow for a weapon that travels faster than light the math breaks down. For example, you can have a ship fire their faster than light weapon and hit the other ship, after the ship is hit but before everyone dies they fire their regular old laser back at the first ship, if the velocities are just right the laser can hit the first ship before they fire their special FTL weapon.

A full explanation can be found here: http://www.theculture.org/rich/sharpblue/archives/... It's the best explanation that I've seen, but to understand it you have to wrap your head around space time diagrams, which isn't easy, especially if you don't have a good understanding of what time dilation actually implies (namely, there's no such thing as two events happening at the 'exact same time' for two different observers).


RE: how about...
By Iaiken on 9/26/2011 12:35:30 PM , Rating: 2
This get's more complicated when you think about computation and data transmission.

I could perform a calculation on a piece of data and then send the answer back in time to the very instant you asked the computer to perform it.

If you want to get even more ridiculous, you can involve two such computers with each other to calculate out non terminating decimals like pi. Each takes a turn calculating the next digit and then sending it back in time to the other which then repeats the process ad infinitum. Technically, you could ask these computers for any single digit of pi instantly as between them they will have calculated them all out.

The relativistic problem then becomes one of exactly when to ask, because neither would have the entire value set available to them nor could they as any attempt to store the data would instantaneously fill all of the storage space.

Fun times!


RE: how about...
By wifiwolf on 9/26/2011 6:46:51 PM , Rating: 2
That would be great but there's a flaw. infinite times an infinitesimal =?

When it's an isolated experiment it's simple, but something repeated infinite times like an infinite precision number, that takes a sum of each elapsed time.


RE: how about...
By JediJeb on 9/27/2011 2:50:25 PM , Rating: 3
The logic problem I have always thought of when asking about FTL communications is this.

If you had a metal rod 1 light year long, and you push on one end of it, when will the other end move?

If it moves at both ends at the same time then you have communicated faster than the speed of light. If that can not happen, then what delays the movement of the other end?


RE: how about...
By Wraithor on 9/27/2011 8:30:33 PM , Rating: 3
I would assume that if you had a set up like this what would happen when you push the rod is that it will compress the amount which you push it and simultaneously decompress at the rate which the particles would allow, for instance if your rod was made up of five 0's this is what would happen:
0 0 0 0 0
]00 0 0 0
]0 00 0 0
]0 0 00 0
]0 0 0 00
]0 0 0 0 0
, or maybe you just destroy the universe.


RE: how about...
By AnnihilatorX on 9/28/2011 3:06:59 PM , Rating: 2
It will still move below the speed of light due to pushing an object really is really subatomic electromagnetic interactions


RE: how about...
By MozeeToby on 9/28/2011 3:16:06 PM , Rating: 2
When you push one end of the rod, the other end moves much more than one year later. A compression wave travels through the metal rod at something closer to the speed of sound than the speed of light. In any normal human scenario that all happens so fast that you'd never notice it, especially in something as rigid as a metal. But imagine you had a meter long rod of jello and you push one end, the other end doesn't move immediately. The same is true of all materials, it just happens more quickly.


RE: how about...
By Mitch101 on 9/26/2011 12:44:23 PM , Rating: 2
Thanks will give it a read.

The neutrino and its ability to pass through matter and its lack of an electrical charge kind of makes me want to throw out the theories that surrounds other items of mass and say maybe this is possible.

I guess that why some believed the neutrino was mass less. Its neutrality makes me feel time shift doesn't apply like other items of charge that are influenced by items such as gravity which can influence light but not keep it from escaping.

But then if she weighs the same as a duck she must be made of wood and therefor a witch. I'll wait for the super scientist to make a nova program that I understand.


RE: how about...
By snakeInTheGrass on 9/26/2011 1:24:09 PM , Rating: 2
Hmm, so we're sitting 4 light years apart. You send me a signal via laser, so at light speed. I reply with an amazing neutrino pulse that I somehow get running at 10x light speed and reply as soon as I get your signal. It arrives back where you are in just .4 years instead of 4 years. You may be able to do something with that given that it arrives before a laser pulse or radio signal, but given a distance to traverse and a given speed, it won't arrive before it was sent in any case.

If you travel at the speed of light, the argument is that you're no longer aging. If faster (infinite energy needs aside?), do you get younger? So if you fly to meet me (FTL), arrive somehow younger, and immediately return (FTL) to your starting place, you maybe (?) are somehow younger, but you still arrive after you left, not before.

Now you go kill your grandfather. You haven't managed to kill your father by killing your grandfather. Your grandfather may wonder what in the world you're up to as you try to kill him, but there's no issue of causality - you can't receive a signal before it is sent just because it's traveling faster than an arbitrary 'speed limit', and you won't arrive before you left either. You won't erase yourself, either. ;)

I DO buy that there could be an ability to transmit data backwards in time should it turn out to be possible to transmit information through quantum entanglement. Take one of the particles, let it travel at near-light speed for a while so that it 'relativistically' ages less, now you have a particle at current time, another at current minus some amount. Should you be able to transmit data from 'current' to the 'current minus some amount' and have that data show up before you send it then? Uh, seems like it. Though so far there's an inability to actually send data.

But anyway, that's a different issue than what is being seen in this case. I suppose light speed could have magical properties, but some of it sounds about as reasonable as the Ptolemaic spheres. It's safe to say that today's concepts in physics will largely look about as advanced as the earth-centric worldview given a few hundred years - and about as ridiculous.


RE: how about...
By Steve1981 on 9/26/2011 2:04:15 PM , Rating: 2
quote:
I suppose light speed could have magical properties


I'm not sure about the speed of light, but I recall watching a documentary indicating that 88mph was the ticket to time travel.


RE: how about...
By cjohnson2136 on 9/26/2011 4:07:50 PM , Rating: 2
I watched that same documentary and it was pretty awesome


RE: how about...
By Omega215D on 9/26/2011 5:47:51 PM , Rating: 2
Observer from Fringe: Their theories are quite fascinating.


RE: how about...
By MarkHark on 10/2/2011 7:42:59 AM , Rating: 2
Did it have something to do with a flux capacitor?


RE: how about...
By MozeeToby on 9/26/2011 3:57:42 PM , Rating: 3
Light speed does have magical properties, properties that 80 years ago made every physicist in the world sit down a drool like the village idiot.

The first hint that this was the case was when someone decided to try to find out how fast the earth was moving relative to the theoretical aether that light supposedly traveled in. The result they got upended physics: You get the same value for the speed of light even if your source and/or your detector are moving relative to each other.

Imagine you have a pitcher throwing balls at the back of a truck and have the pitches arrive at the truck at the same speed regardless of how fast or even which direction the truck was moving in. It doesn't work, it breaks all kinds of classical mechanics and the math doesn't work out at all.

Unless, that is, you assume that time isn't passing at the same rate for the person throwing the ball and the person catching it. And that the distance the ball travels isn't quite equal if you ask the pitcher and catcher. And that's exactly what happens when you approach the speed of light.


RE: how about...
By JediJeb on 9/27/2011 3:02:20 PM , Rating: 2
If I am an observer at a point in space and I can see two stars one light year apart. I see a person leave one star and travel to the other star at the speed of light, then I should observe that it took them 1 year to travel that distance. How long does it appear to the person traveling at the speed of light that it took them to get there?

If by the travelers clock it took less than one year, then from their point if observation they traveled faster than the speed of light since they traversed 1 light year is less than one year. If from the travelers point of view it took them 1 year to traverse the distance of 1 light year then they did not experience time compression. How long will the journey appear to take from the two points of observation?


RE: how about...
By MozeeToby on 9/28/2011 3:22:56 PM , Rating: 2
You have a good handle on time dilation but you're forgetting other relativistic effects. Observers on the ship traveling at .99c will measure the journey time as much less than a year, what they will disagree with the outside observer is the distance between the two stars. To them it will be much less than 1 light year.


RE: how about...
By JediJeb on 9/29/2011 4:55:31 PM , Rating: 2
But if the observers on the ship know before hand that the distance is 1 light year then would they not have to assume they traveled faster than light to make the journey in less than one year?

I guess another question I have about it is whether or not Time actually slows at velocities near the speed of light or is it simply that with the increased mass/inertia that comes from traveling at those velocities causes our measuring devices to slow down which would give the perception of time slowing down?


RE: how about...
By rakarlin on 10/1/2011 11:11:22 PM , Rating: 2
Thank you. The nonsense about causality violation was getting a little deep. Now, if you can make time go negative we have a whole new situation. But at velocity C or 2C or 10C it still takes positive time to get someplace; in fact to get anyplace. Regards


RE: how about...
By zmatt on 9/26/2011 4:45:03 PM , Rating: 2
causality isn't some golden law that was passed down from the gods. It is entirely possible (although very unlikely) that causality can be violated. We just haven't seen it yet. A lot of people get uppity about stuff like this and they toss out the "it violates causality so it's impossible" argument. Given what we have seen things like this shouldn't happen and so far causality has been good, but rule #1 about science is nothing is set in stone.

As far as this announcement, I'll hold judgement until the scientific community chimes in and we see if it stands up to the scrutiny.


RE: how about...
By JediJeb on 9/27/2011 3:06:01 PM , Rating: 3
If it is true that there can be multiple timelines causing infinite parallel universes then it would be possible to return to the past and kill your grandfather and still continue to live. You would simply cause a fragmentation of the timelines at that point and start another parallel universe where you were never born, yet your timeline continues as if nothing ever happened.

Possible?


RE: how about...
By Phoque on 10/2/2011 10:11:31 AM , Rating: 2
quote:
3) The same way you can distinguish the light of the sun from the light of your Display.


No, read back 5th paragraph of section III.


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