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09-23-2011, 10:28 PM #17
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Re: "Faster than Light Measurement Challenges Relativity"

Quote:
 0.002437165 seconds would take for light to go 454 miles 0.002437215 seconds they measured, or 0.00002% faster... couldn't go far back in time with it heh.
Sorry, but something seems to be incorrect with your calculation.
If neutrinos are faster then light, how can the time they traveled be bigger?

Light would need 0,002435017895 seconds (I calculated with 730km and c = 2,99792458 * 10^8 m/s)
They measured the Neutrinos were 60 nanoseconds faster, so thats a total of 0,002434957895 seconds.

The velocity of the neutrionos was 2,997998452 * 10^8 m/s.

So this means the Neutrinos were 7387,2 m/s faster then light, which is 0,002464% and thats may not look much more, but that means every seconds they travel more then 7 kilometers more then light, and thats to much to be a simple mistake.

If we can get enough energy to speed up neutrinos over the speed of light, it means the energy we need is not infinite like we thought till now. And that means it IS possible to travel and send informations with lightspeed and even faster, and even if it does not chance much for practical physic, it DOES chance our view of the universe and how it works...

just my 2 cents

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Last edited by MadEye; 09-23-2011 at 10:33 PM.

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09-24-2011, 07:12 AM #18
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HIMNL9
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Re: "Faster than Light Measurement Challenges Relativity"

Quote:
 Originally Posted by chipdouglas but why does light in in or out of vacuum make a difference to this experiment. there is a know distance and light in c is constant. so if c doesn't add up to the known distance then obviously they werent comparing it to light c.
Well, no, light speed is a constant only in a known, given medium (in this case, "c" is referred to light speed in the vacuum), and changes with the density of the medium that it need to cross through ..... in atmosphere, that have a higher density than vacuum, light speed is slower than "c".

It depend directly from the "refractive index", and can be calculated as "speed in medium = c divided refractive index of the medium" .....

As far as i remember, in vacuum is something less than 300.000 Km/seconds, and air refractive index is 1.0003, this means that in the air, the light is approximatively 90 Km/s slower than in the vacuum.

EDIT: finally found some informations about the experiment here, but are very limited.
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Last edited by HIMNL9; 09-24-2011 at 07:40 AM.

09-24-2011, 10:27 AM #19
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Re: "Faster than Light Measurement Challenges Relativity"

Actually, light ALWAYS travels at c, the speed of light in vacuum. The refractive is the medium oscillating with the light but in a slighly different phase. When the medium reradiates the absorbed photons it does so with a delay. That's the effective lower speed you measure, the photons themselves won't travel slower.

If you want to be faster than light in a medium check out cherenkov radiation, that's sort of the sonic boom of light, but that has to be in a medium. It's the blue glow from the cooling water of nuclear reators.

It would be nothing new that neutrino's can beat the effective speed of light in a medium, the thing it that it is faster than the vacuum light speed. If something can travel faster than the vacuum light speed something very strange and new is going on, something the wide theory of relativety doesn't cover, that's why it's exciting.

Measuring a 60ns time difference is very easy, common agilent universal counters measure intervals with 20ps resolution and typically have a 0.3 parts per billion accuracy after calibration (agilent 53230A w/ opt 010). They know what they are doing, so I won't question the result easily that fast.
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09-24-2011, 03:59 PM #20
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Re: "Faster than Light Measurement Challenges Relativity"

I have experienced all of this matter myself some time ago,...
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09-24-2011, 06:04 PM #21
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Re: "Faster than Light Measurement Challenges Relativity"

How? They are difficult to detect. The detector used weighs over 1300 tons!

Apparently, my mother's high school friend works at the LNGS at Gran Sasso.
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09-26-2011, 03:01 AM #22
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Re: "Faster than Light Measurement Challenges Relativity"

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