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The Speed Of Gravity Revealed
redwolfoz writes "New Scientist is reporting that the speed of gravity has been measured for the first time. 'The landmark experiment shows that it travels at the speed of light, meaning that Einstein's general theory of relativity has passed another test with flying colours.' Researchers made the measurement of the fundamental physical constant with the help of the planet Jupiter. One important consequence of the result is that it will help constrain the number of possible dimensions in the Universe."
Wow, that's pretty cool. Now if we could only figure out why and how gravity works, we'd be in business.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
But of course, travelling at the speed of light, all the flying colours just appeared red due to the red-shift.
Does this make my brain look big?
Sure, this experiment will "help constrain the number of possible dimensions in the Universe" ... but will it lead to new weapons?
-kgj
Sure, we could pull Saddam out of Iraq with a gravity generator ... pull out the Tigris and Euphrates, while we're at it -- the whole damned Cradle of Civilization.
-kgj
Something doesnt have to have mass to have speed. Plonk a stone on a pond, you create waves. The waves have speed but dont have "mass" per se. Gravity in general relativity is similar. The entire universe is immersed in Space-time (kinda like water in a pond). Objects inside spacetime tend to "warp" spacetime. Like poking a finger into a stretched rubber sheet, creating a depression. So objects near them tend to tumble into the depression - bingo! this is gravity. This is what general relativity says. Now if this is true, warping in spacetime cannot occur instantaneously (no wave travels faster than light) as assumed in newtonian mechanics. This is what has been proved now. "Distortions in space-time does not propagate faster than light" or in other words "gravity does not travel faster than light". So no "mass" or "moving object" is involved per se.
Well, now we have the speed of light AND the speed of gravity! If we can find out the Speed of Darkness, we'll be all set!
I prefer to think of it as having no loose ends...
___
If you think big enough, you'll never have to do it.
"mass equivalence" hmm that means photons are almost the same as that stuff that was laying on the plate on thursdays back at my old junior high. It was a meat-like equivalent.
YESSS! In your FACE, Infinite-dimension Universe theorists! You SUCK!
Yeaaaaah! Gimme one up top, bro!
pr0n - keeping monitor glass spotless since 1981.
the energy of a photon has a mass equivalence, but it does not have mass
Bastard. I'm going to have sleepless nights trying to figure out what the hell you mean by that. This is not the kind of concept mere mortals like me should have to deal with while sober.
People couldn't type. We realized: Death would eventually take care of this.
Sonny Bono's failure to grasp rudimentary physics can be seen as yet another case of evolution in action.
But can Sonny Bono's failure to grasp rudimentary constitutional law be seen as yet another case of evolution in action?
Will I retire or break 10K?
...you see, it's all component forces. If you look at the free body diagram of my car travelling on the road, you'll see the normal force, force of gravity, and my velocity in the x direction. As I mentioned, one of these component forces is gravity, labelled FsubG. It was recently discovered, and posted on slashdot, that the speed of said force is 3x10^7m/s.
And THAT'S why, officer, your radar reported that I was going 60 in a 40 zone!
One important consequence of the result is that it will help constrain the number of possible dimensions in the Universe.
You're damn right. I was worried.
Dimensions running rampant without limit... what's next, violent television and people masturbating???
It's a sad, sad world. Good thing we have that dimensional problem under control!
I asked my physics teacher the very same exact question- "if the sun disappeared, would the earth fly off from its orbit instantly, or would it take about 8 minutes?" He goes "it would be like snipping a cord- instantaneous". Discouraged, I went into the slashdot-posting, linux compiling netadmin that I am today, never knowing the true path of lab coats, leather gauntlets, and welding glasses that is physics- How dare you Stockwell! You stole my life with an assumption and I want my five years back!!!
slashdot: where everyone yells sarcastic metaphors to themselves to understand the issue
"Remember the Unified Field Theory? Well, forget it. Physicists have pretty much thrown in the towel on unifying gravity with the other elemental forces, so now we have the Standard Model, which says that everything works together in intricate harmony except gravity, which is on holiday in Tasmania and need not concern us further."
- Jon Carroll on the Higgs Boson
Nerd: Derogatory term typically directed at anybody with a lower Slashdot ID than you.
"You can't go faster than the speed of light."
"Of course not. That's why scientists changed the speed of light in 2208."
... in fact, light is travelling at the speed of gravity.