NASA | Einstein's Cosmic Speed Limit Video

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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-space-is-made-of.html

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

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Rampant7990: If you do the research, you will find that he used "God" as an example to explain things at times, but he was not a believer. "It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."

shaochiavang: yeah, but science only answers how questions, and not why questions :). i believe in GOD, and i find science intresting, idk why

theradarguy: Looks like NASA just proved the existence of ether! woohoo!

HackneyEquine: no I have not. but I will try it on your recommendation. *gigglesnort*

onthecuttingedge2005: I have been saying for thirty years now, have you just been catching up?

sbarbarar: I think you may safely infer that the high energy waves were emitted 900,000 milliseconds after the lower energy waves. Considering they mention that before the Fermi observations. Mathematically, 900 milliseconds over 7,000,000,000 years is negligible, it translates to 4.07426974 × 10-18th difference in arrival time.

Offlinedream: So if you go back to that ball rolling on the bubble wrap experiment. One ball is bigger and one ball is smaller. The question is if they're both travelling at the same speed then how could 1 reach the destination earlier? Well. If you have a basket ball and a golf ball moving through space at the same speed and the golf ball is positioned accordingly to the basket ball's center but side by side and they both are reaching a line. The basket ball will hit it first. Why? It's bigger. My theory.

chumbawomba: Under the electric universe - the higher energy gamma ray will be influenced by electromagnetic plasma interference. Enough to slow it fractionally. This is very old - pre dating - grand unified field theory - which is nonsense as it does not account from electromagnetism. One of the four forces in the universe???

Ironbob2006: Maybe God believes in science too.

ComputerGeek396: The god of the gaps.

masonhosey: I thought they slowed light down to a standstill. How is that a constant? Oh, and its very silly to enforce a cosmic speed limit based on one's misunderstading of causality

masonhosey: yeah, ether is starting to sound a lot like dark matter

tulsaguy1974: Excellent video! I loved it.

Riste1986: Einstein reveal everything for them so now they can talk that Einstein is wrong omg. And they are saying Could he be wrong so they can confuse you to actually think that he is wrong. NASA is WRONG. They want to be better with no hard facts .

chochopie: I said instigate not investigate. Read some more books you need the practice.

locomotive147: yo' but God wouldn't allow this!

poormansvideo: it's amazing how Einstein known all of this stuff without spaceships or .. gigantic telescopes or whatever you can think of NASA's advance technology .. If Einstein has made an Time Traveling machine .. How I wish he visit me .. I have a lot of questions for him.

GeneralBerger: I would personally want Tesla to visit me. Tesla!!!

poormansvideo: err.. me!

ashleylovesdaddy: 186,000 miles per second is the speed of light in a vacuum. It's a constant only when referring to a vacuum. It has a different speed in other mediums. Hence the rainbow. Or think of the waviness on the bottom of your pool in the daytime. You're still learning.

masonhosey: YEAH, I know... I was being silly.. They did slow it to a stand-still, though, didn't they? I think it was 80,000 mps through diamond, 38 mpH through sodium at -272 deg C... and a complete standstill through Bose-Einstein Condensate of rubidium

ashleylovesdaddy: I'm still learning too. I didn't mean to sound like an asshole. I assume you saw the special on NOVA about absolute zero? Check on hulu. And The Universe episode about light speed. I can't afford to go to college so I'm an armchair college student. And what's with chumbawumba down there? On and on and such.