NASA | Einstein's Cosmic Speed Limit

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In its first year of operations, NASA's Fermi Gamma-ray Space Telescope has mapped the entire sky with unprecedented resolution and sensitivity in gamma-rays, the highest-energy form of light. On May 10, 2009 a pair of gamma-ray photons reached Fermi only 900 milliseconds apart after traveling for 7 billion years. Fermis measurement gives us rare experimental evidence that space-time is smooth as Einstein predicted, and has shut the door on several approaches to gravity where space-time is foamy enough to interfere strongly with light.

To read more about the science behind the story:

Late light reveals what space is made of : http://www.newscientist.com/article/mg20327210.900-late-light-reveals-what-sp...

A limit on the variation of the speed of light arising from quantum gravity effects:
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature08574.html

Category:

Science & Technology

Tags:

• nasa
• goddard
• space
• flight
• center
• albert
• einstein
• cosmic
• speed
• limit
• light
• photons
• time
• relativity
• quantum

[trZack]

Wasn't this proved wrong with the discover of neutrinos? 

[eliasm307]

didnt she just say they arrived 900ms apart?

[Venoxisify]

@trZack those morons scientist can't seem to understand that neutrinos accelerate faster then light but don't travel faster than light, meaning they will arrive first at the target just because of acceleration, but the speed remains constant.

[Venoxisify]

damm she talks at the speed of light!

[ttJinn]

@eliasm307 Let me break it down for you.

900ms difference in 7 billion years, that's 1ms = 10^-3s difference per 7.77~ million years.

10^-9s per 7.77~ years.

4.07697327 x 10^-18s per second.

The difference in energy and wavelength between the HIGHEST ENERGY and LOWEST ENERGY photon has to be around or lesser than the amount required to produce a difference of, in distance of light, 4.07697327 x 10^-18s per second.

A more probable theory would be that one of the photons was discharged earlier.

[zachgosteady]

@iamgig9876 yes "idiot", neutrinos were "discovered". How else do you think scientists started to study them? In 1933 when they were first DISCOVERED by Reines...that's how

[iamgig9876]

@trZack "discover" really?? they just discovered neutrinos? obviously you are an alien to physics... now anyways that was proved wrong.. who the fuck in the right mind uses a damn gps mounted on a fucking satellite which is ACCELERATING to measure a beam travelling across europe? thats right, idiots like you...

[lose1000]

@FlyKingRy That is mass and energy relationship. E=(m)(c)(c).

That is just for indicate that when how much energy can release when mass deflect occurs on an non-zero mass objects. But not the evidence of "a possible velocity of C * C ."

[matt876mma]

@randy95023 Einstein said, ''nothing can travel faster than the speed of light''.  What does that mean? It means he said light was the fastest ''thing''. So there you go mr.smartypants.

[randy95023]

The novice mistake that many people make is that "something out there can travel faster than light". The point is NOT that light is the fastest "thing", it is that light reaches the highest velocity possible for anything with mass. In other words, If something could travel faster than Light, then Light itself would travel faster than it does. It's not just semantics, it's Mathematics!