Germans claim to break the speed of light

[DJBruce]

It found this I know its not a very good source but I think that this is intresting and could be very big.

 

http://www.g4tv.com/thefeed/blog/post/678547/Germans_Break_The_Speed_Of_Light.html#readmore

 

Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz in Germany, claim to have broken the speed of light. They have conducted an experiment in which microwave photons traveled "instantaneously" between a pair of prisms that had been moved up to 3ft apart, which would be faster than the 186,000 MPH that Albert Einstein once said would take an infinite amount of energy to power.

 

I also have a question if microwaves are part of the Elecormagnetic spectrum dont they already go at the speed of light?

[Klaynos]

A better source:

 

http://www.newscientist.com/article/mg19526173.500

 

Which if you read the whole thing you will see that no individual photon is violating SR.

[swansont]

For some reason my library login to New Scientist isn't working; none of the links I read mention what journal this research appeared it. Anybody have the cite? Until one can review the details of what they did, I would caution taking the popular accounts of the experiment with a huge grain of salt. (And if it hasn't been written up, all I will say is: remember Pons & Fleischmann)

 

My early wager (betting blind) is that the measurement (or the reporting of it) is mixing up phase and group velocity.

 

edit: http://nanoscale.blogspot.com/2007/08/superluminality.html (a comment, not a cite)

Pulse reshaping, i.e. phase velocity effects

 

and more: http://www.centauri-dreams.org/?p=1406

 

Apparently there is no journal article, only something posted to ArXiv

[Klaynos]

I see thanks for the research swansont....

[duckandcover]

It has not turned up on IOP yet

[alan2here]

come on people, some analysis of the significance of this and general explanation for those that don't understand about what is happening.

[Klaynos]

Think of it like this (example used in new sci article), a train leaves a station traveling 100mph, after each mile it leaves a carraig behind. After an hour it stops, with just the front carriage left. If you measure from the mid point of the train the total distance traveled it will be more than 100miles, so by this measurement the train has traveled faster than 100mph but no individual carriage has done.

[Money]

in the article it said microwave photons traveled faster than the speed

of light photons are light, so whats the difference between microwave

photons and normal photons? how can u make light faster than light?

[swansont]

in the article it said microwave photons traveled faster than the speed

of light photons are light, so whats the difference between microwave

photons and normal photons? how can u make light faster than light?

 

Microwave photons just have a particular range of wavelength; microwaves were probably chosen for ease of doing the experiment.

 

It's measurement bookkeeping sleight-of-hand, like the example Klaynos summarized. No information went faster than c. Nothing violated SR. Just another pulse-reshaping experiment that bedazzles science journalists.

[Dak]

Think of it like this (example used in new sci article), a train leaves a station traveling 100mph, after each mile it leaves a carraig behind. After an hour it stops, with just the front carriage left. If you measure from the mid point of the train the total distance traveled it will be more than 100miles, so by this measurement the train has traveled faster than 100mph but no individual carriage has done.

 

so If you could make a devise that somehow detected the centre of the train, and placed it 100 miles away from the trains centre, and the train went at 100mph dropping carriages, wouldn't the centre of the train be detected just slightly under an hour later?

 

i.e., wouldn't information have been transmitted faster than 100mph, even tho it's phisical container (the train) was only going 100mph? in theory, couldn't you transmit inforomation like this at a rate faster than 100mph? or, with the OP, faster than the speed of light if the centre of the photon (photon group?) could be detected?

 

btw, by 'information' i'm meaning that you could transmit a signal from trainstation to train-centre-detector. not sure wether that'd count as information in the phisics sence.

[swansont]

Each car of the train carries all of the information of the train in this analogy. So detecting the front of the train only appears to violate the speed limit. What really happened was you changed the detection point (redefined the center), and the speed at which you do that is not restricted.

[Dak]

when i said detect, i meant not only 'detect the bit that happens to be the centre', but also 'detect the bit that is the centre, soley by the fact that it is the centre' (i.e., detect the centre by any special qualities it posesses by being the centre).

 

imagine the following train:

 

- - - x - - -      x = centre
 A   B

 

now, B removes the carriages above it:

 

- x -   - x -
 A   B

 

A now instantaniously detects a centre (and thus the signal from B), IF the centre can be directly detected as the centre?

 

I'm more interested in why not, rather than suggesting the above is the case btw. i'd guess that any way of measuring the centre would require waiting for any changes to propogate through the 'train', which would happen at < c.

[scalbers]

The preprint is posted on arXiv.org - here's the link: http://arxiv.org/abs/0708.0681

[Norman Albers]

Seeing developments in metamaterials a few months ago I asked if a reduction in the permittivity of the "vacuum" medium, somewhat below unity, could be engineered ???

[Klaynos]

Seeing developments in metamaterials a few months ago I asked if a reduction in the permittivity of the "vacuum" medium, somewhat below unity, could be engineered ???

 

No. Metamaterials don't actually change the permittivity of anything they just create an effective permittivity due to resonances. As there is no material to actually engineer in the vacuum you can't do much with it.

 

You can build negative refractive index materials though.

 

One thing that should be remembered when discussing this is that you can only relly get the materials to work for a single wavelength at the moment. I spent 10 weeks last year trying to engineer materials with resonances for 2 or 3 frequencies in the visible domain. It is NOT easy.

 

In reply to Dak, I'll reread what you wrote when I'm less tired

[Norman Albers]

Thanks for a knowledgeable answer, Klaynos.

[stormwarrior]

SO the laws of relativity which is based upon the speed of light as Einstein wrote have been shown to be wrong... What changes will this have on quantum physics that cornerstone on the law of relativity? Its boggling isnt it. I guess the world really isnt flat after all

[iNow]

SO the laws of relativity which is based upon the speed of light as Einstein wrote have been shown to be wrong...

 

How do you figure that? Have you even read the other 15 posts in this thread? Are you familiar with all of the empirical evidence in support of both SR and GR?

[stormwarrior]

Ok lets start on the right foot here.

 

Theory.

The speed of light has been broken claimed and proven by scientists. Evidence:

The research of those scientists.This evidence can be reproduced. Sources cite these facts very well.

 

Conclusion:

The speed of light is no longer the end all be all as Einstein had thought in relative terms.

 

Speculation: Relativity needs to be reworked to form a new theory.

 

I read each of the posts that explain nothing and speculate in varied different directions.

 

I find it to be amazing and I am sure that if Einstein were here he would have a good deal to say about the modern world he helped to invent.

 

The world is not flat. Not only is it round but its full of people!

C S S

 

http://www.cbc.ca/health/story/2000/07/20/...ight000720.html

"Scientists have finally exceeded the speed of light, causing a light pulse to travel hundreds of times faster than normal. It raced so fast the pulse exited a specially-prepared chamber before it even finished entering it. The experiment is the first-ever evidence of faster-than-light motion."

 

Friday, August 17, 2007

Once again, Tesla was right: He challenged Einstein's theory of relativity and said that particles COULD exceed the speed of light

Scientists break speed of light in lab test

 

IT was supposed to be the one speed limit you could not break.

 

But scientists claim to have demonstrated there is the possibility of travel faster than the speed of light.

 

The feat contradicts one of the key tenets of Albert Einstein's special theory of relativity - that nothing, under any circumstances, can move faster than 300,000km a second, or the speed of light.

 

Travelling faster than light also, in theory, turns back time.

 

According to conventional physics, a person moving beyond light speed would arrive at his destination before leaving.

 

But two German physicists claim to have forced light to overcome its own speed limit using the phenomenon of quantum tunnelling.

 

Their experiments focused on the travel of microwave photons - energetic packets of light - through two prisms.

 

When the prisms were moved apart, most photons reflected off the first prism they encountered and were picked up by a detector.

 

But a few appeared to "tunnel" through a gap separating them as if the prisms were still held together.

 

Although these photons had travelled a longer distance, they arrived at their detector at the same time as the reflected photons.

 

This suggests the transit between the two prisms was faster than the speed of light.

 

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

http://weazlsrevenge.blogspot.com/search/label/Tesla

 

This is the other article

[swansont]

Ok lets start on the right foot here.

 

Theory.

The speed of light has been broken claimed and proven by scientists. Evidence:

The research of those scientists.This evidence can be reproduced. Sources cite these facts very well.

 

Conclusion:

The speed of light is no longer the end all be all as Einstein had thought in relative terms.

 

Speculation: Relativity needs to be reworked to form a new theory.

 

Speculation: you need to read up on anomalous dispersion, and the difference between group velocity and phase velocity.

[pioneer]

Phase velocity I believe is sort of the affect we get during refraction, such as when light bends in water. The light enters the material. Light creates an alternating electric field that will cause electrons or charge to vibrate, trying to align with this alternating field. This gives off energy that will be slightly out of phase with the incoming light wave. This will subtract from the original waves without alterring the phase frequency. The final composite wave (frequency time wavelength) appears to go slower than the speed of light. It does not. It is a composite affect.

 

The affect theses scientiists may have created is where the material increases the phase velocity without alterring the frequency, such that wavelength times frquency muliples to greater than the speed of light. This is interesting, since the material will need to get ahead of the phase of the electric field that is being generated by the light.

 

One possible way this might be occur is a falling behind will cause the wave phase to eventually get in front of the incoming wave. For example, if I was running on a track and a faster runner passed me, I would fall behind. But as he catches up again, after already lapping me, I will be ahead, if we do not take into consideration the very first cycle. Visually, the refraction would bend, bend, bend, then poof, faster than C??? At least the wavelength time frequency would be greater than C.

[stormwarrior]

Speculation: you need to read up on anomalous dispersion, and the difference between group velocity and phase velocity.

 

I will do that but why bother. if an object is moving faster then c=3000000km per second, then faster then light is proven because c=3000000km per second is the speed of light even regarding phase velocity or group velocity.

 

Remember we are not talking about appearence of light we are talking about speed of light.

 

Seems pretty logical to conclude that the barrier is hitherto broken and relativity is questionable with the evidence given.

 

would you agree with that statement?

[insane_alien]

nope. because if you read up on it, nothing actually goes faster than light. it only appears to. you can't do anything useful with it.

[Norman Albers]

Pioneer, the actual speed of light measured by us not in the medium is less than c according to multiplication by the inverse of the index of refraction. Meditate on [math]\epsilon_0[/math], the electric permittivity of the vacuum. This very idea says that the vacuum acts like an availability of polarization. An optically clear but thicker medium, i.e. with higher index, adds more of this polarizability. It's like after church service (as a kid) we all stood in line to shake the pastor's hand. The shaking was mutual so no net energy was exchanged, yet the line moved slowly.

[swansont]

I will do that but why bother.

 

Because you might learn some physics?

 

The actual implications of relativity and causality are a little more involved than incorrectly thinking that you'll never get a number bigger than 3e8 m/s. That's the watered-down tabloid version of things.