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'We have broken speed of light'

By Nic Fleming, Science Correspondent
Last Updated: 12:01am BST 16/08/2007

A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time.

According to Einstein's special theory of relativity, it would require an infinite amount of energy to propel an object at more than 186,000 miles per second.

However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory.
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The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of prisms that had been moved up to 3ft apart.

Being able to travel faster than the speed of light would lead to a wide variety of bizarre consequences.

For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.

The scientists were investigating a phenomenon called quantum tunnelling, which allows sub-atomic particles to break apparently unbreakable laws.

Dr Nimtz told New Scientist magazine: "For the time being, this is the only violation of special relativity that I know of."


www.telegraph.co.uk/earth/main.jhtml?xm ... eed116.xml

If true this is absolutely awesome.

I never understood how Time is dependent on the speed of Light anyway....I mean, fast is fast isn't it? You can't go faster than Time itself can go, can you?

I've never heard that time was dependent upon the speed of light. But speed of light definitely allows for some interesting time paradoxes. Really, I'm not even sure why the universe has an ultimate speed limit in the first place. Another one of those facts I've forgotten over the years. Sounds like a trip to Wikipedia is in order.

Esmer--it's related to the idea of the speed of light being the fastest you can go. The reasoning goes as follows:
-If an object moving at X m/s relative to an observer then projects some other object at Y m/s relative to itself, the observer would see the object moving at X+Y m/s.
-If the object is a light source, and the projected object a photon of light, then the observer would see the light moving at X+c m/s (where c is the speed of light)--however, the speed of light cannot be exceeded, so this is impossible.
-The light photons must move at c relative to both the observer and the light source--which seems impossible, but has been proven in experiment--no matter who observes light moving, they always see it travelling at c.
-It follows therefore that time itself must flow differently for people moving at different velocities--the observer sees the light travelling at c relative to itself; and an observer moving with the light source experiences a slower flow of time, causing it to see the light moving at c relative to itself also.
If this was not true, light would have a variable velocity.

Murrin wrote: If this was not true, light would have a variable velocity.

But what's wrong with a relatively variable s.o.l dependent upon one's reference frame? The most I could get out of Wikipedia is:

One consequence of the laws of electromagnetism (such as Maxwell's equations) is that the speed c of electromagnetic radiation does not depend on the velocity of the object emitting the radiation; thus for instance the light emitted from a rapidly moving light source would travel at the same speed as the light coming from a stationary light source (although the colour, frequency, energy, and momentum of the light will be shifted, which is called the relativistic Doppler effect). If one combines this observation with the principle of relativity, one concludes that all observers will measure the speed of light in vacuum as being the same, regardless of the reference frame of the observer or the velocity of the object emitting the light. Because of this fact, one can view c as a fundamental physical constant. This logic is the basis of the theory of special relativity.[3]

So it's a consequence of Maxwell's laws. This sounds vaguely familiar from my college physics classes I took years ago. But it's still counter-intuitive. Why should the speed of EM radiation be independent of the speed of its source?

Malik23 wrote:But what's wrong with a relatively variable s.o.l dependent upon one's reference frame?

My EXTRAORDINARILY inadequate understanding of all this is that it's not a matter of "what's wrong with [it]." It's a matter of it is the way it is. As Murrin said:

-The light photons must move at c relative to both the observer and the light source--which seems impossible, but has been proven in experiment--no matter who observes light moving, they always see it travelling at c.

That's the end of the story. Who would imagine such a thing being the case? (Einstein, I guess. ) Yet, when checked, that's the way it is. So it's now a matter of understand how such a thing can be. (Personally, I am clueless.)

I must add that Quantum Tunneling is more the effect of the unpredictability of a particle's position. In the sun's core, there isn't enough energy for particles to reach the level where they can fuse (that is, overcome natural repulsion) and create a fusion reaction. There's an area of particle 'fuzziness' where the particle might be. When tunneling is taken into account, the particles can theoretically fuse despite their energy level (or requiring a massive amount of energy). So one, or both, tunnels instead of achieving a higher energy level. I suppose in the same way, the particle in the experiment HLT mentioned doesn't exceed the speed of light, just 'quantum jumps'.

I fully expect to wake up one day to the visual and sound of the world somehow imploding on itself. It's just a matter of time before some genius sets in motion a particle acceleration accident that causes a massive singularity.

Chew on that and be dismayed.

Malik23 wrote:So it's a consequence of Maxwell's laws. This sounds vaguely familiar from my college physics classes I took years ago. But it's still counter-intuitive. Why should the speed of EM radiation be independent of the speed of its source?

Because otherwise we'd live in a paradoxical world. If radiation was dependent upon the speed of its source, then we could have V (velocity of moving object) + C. Someone riding a bike down a road and dodging a truck traveling perpendicular to his direction of travel would appear to dodge the truck before the truck crossed his line of travel (his image would be forced to appear sooner if V+C).

I always to it as given that Einstein was wrong about it being impossible to travel faster than light. One way or another.

--A

I think the discrepancy is relative to our perception of light, or energy.

For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.

I think it would just be very dark at his destination until the light caught up with him, granted there wasn't any light already there. This is where my time conundrum comes in. You can't arrive before you leave, no matter how fast you are going. This says if you flew around the world you could meet yourself before you started, and thats why I can't accept it.

Esmer wrote:I think the discrepancy is relative to our perception of light, or energy.

For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.

I think it would just be very dark at his destination until the light caught up with him, granted there wasn't any light already there. This is where my time conundrum comes in. You can't arrive before you leave, no matter how fast you are going. This says if you flew around the world you could meet yourself before you started, and thats why I can't accept it.

I have to agree that this event wouldn't be allowed. Besides, the energy required to exceed C is momentous - the ship would possess more mass than fuel.

Bah, time is pretty imaginary...the way we use it anyway. Or if not imaginary, at least arbitrary.

--A

Avatar wrote:Bah, time is pretty imaginary...the way we use it anyway. Or if not imaginary, at least arbitrary.

--A

I disagree. The very fact that entropy and radioactive decay exists reveals time is anything but imaginary.

Well, I did specify the way we use it.

But what I really meant was that Esmer's example doesn't mean that you'll meet yourself. It's a reflection of subjective time.

--A

Avatar wrote:Well, I did specify the way we use it.

In that we separate it into discrete units? Even then, time is discrete (at Planck time).

Avatar wrote:But what I really meant was that Esmer's example doesn't mean that you'll meet yourself. It's a reflection of subjective time.

How is it subjective, and how do you know he won't meet himself?

According to the theory you must meet yourself, if your destination is your starting point. And you would never stop! You would be caught in an infinite loop!

In that we set an arbitrary point and call it X time. If time wasn't imaginary, how could daylight savings time be possible?

He can't meet himself because he as an individual is always moving forwards. He might arrive before the time thathe left, but he will not pyshically be present, because he (in himself) did leave, and did make that journey which required that time elapse.

--A

Avatar wrote:In that we set an arbitrary point and call it X time. If time wasn't imaginary, how could daylight savings time be possible?

But that's not time. The passage/flow of time doesn't change because we alter hours. Time is independent to human culture.

Avatar wrote:He can't meet himself because he as an individual is always moving forwards. He might arrive before the time thathe left, but he will not pyshically be present, because he (in himself) did leave, and did make that journey which required that time elapse.

--A

So he can't meet himself before the journey? Where is the basis for suggesting that your scenario happens?