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Double Pulsar Discovered
jabberjaw writes "Nature is reporting that a set of two pulsars could be emitting gravitational waves. Einstein predicted the existence of gravitational waves in his general theory of relativity, but a gravitational wave has yet to be detected. Find out more about gravitational waves and pulsars at Eric Weisstein's World of Physics."
Just on an intuitive level, at least. Gravity is a lot like electro-magnetism, in that it produces it's effects invisibly. That, to me at least, implies some method of energy transfer. Waves seem a reasonable enough explanation. I wonder though, if the same wave/particle duality will be observed as we see in photons. Cool stuff.
How fast is gravity?
If the sun went poof, how long would it take for Earth to go off into space? 8 minutes or as soon as it happened?
The answer is a resounding...we dunno!
We have determined that it is at least 2x10^8 m/s, however, it may be as much as 3.6x10^8 (faster than light). We honestly don't know. I'm pretty sure I heard my quantum mecanics professor at the University of Arizona mention something about Einstein's theories requiring light and gravity to equal in speed, but I'm an aerospace engineer, not a quantum physicist. If they do equal...if the sun were to disappear, we would see the light of the sun and still be fine orbit wise for about 8 minutes. Kinda funny to think about.
As for the faster-than-light communications, we could do that with tangled photons. Einstein was troubled by the fact that quantum entanglment causes an instantaneous change across a large distance. It's been used in a large number of sci-fi novels, including Orson Scott Cards Ender's Game series of books.
The detection of these waves could revolutionize physics! It would allow us to determine the existance of the graviton, and if we ever did that, the world as we know it would change. Because once we pin it down, we can start converting energy to it, and probably start research on a feasible "anti-graviton" of sorts. Warp Drives, here we come! (well, not likely, but a guy can hope)
What are you talking about? There is no such thing as an "anti-graviton" since the graviton is its own antiparticle, like the photon is. And how would detection of a gravitational wave help advance technology as opposed to pure science? Pure gravity research is not exactly known for its technological applications.
And it isn't obvious how we will start "converting energy" into gravitons once we've succeeded in "determining their existence". Except in a trivial sense, like when you push a rock up a hill. But you can do that now.
I'm really thinking you are completely under estimating the importance of the sun here.
The planet is under CONSTANT stress from the pull of the sun, and it compensates in more ways than I can even imagine. Suddenly, that force is gone.
What happens when you lean against a leash ( what? I was a very hard to control child, leashes seem like a perfectly reasonable idea at the time ) while someone is holding the other end. Suddenly, they let go, without you expecting it. You fall on your face.
That is exactly what would happen. The interactions between the sun and the earth ( and let's not forget the moon's role in all this ) would go to hell in a mere matter of seconds ( if that long ). I could see the opposite side of the earth not knowing anything for up to an hour, at most, but even that is being generous I think.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
The Standard Model of particles says there's no graviton, that's who! :)
:] )since we've never actually observed one and there are hints that the Standard Model may break soon (though it must be noted that it is the most sucessful theory at describing our universe ever devised). Then who knows what the superseding theory (supersymmetry? strings?) will say about quanta of gravity.
You said:
"No, the graviton can very well have an anti-graviton and a photon an anti-photon. The argument against it would be that both things don't have a charge...well neutrinos don't have charges either, but they have anti-particles."
You're misunderstanding why Photons Gluons and presumably Gravitons, if they exist, do not have anti-photons, anti-gravitons etc. and are actually THEIR OWN ANTIPARTICLES. It is not because they have no charge, that's irrelevant, it's because they are Bosons which are particles with integer spin. The chargeless Neutrino and anti-Neutrino are Fermions which have non-integer spin. I would suggest a look at CERN's The Particle Adventure site if you want to learn a bit more about subatomic particles, it's a great site.
However, this being said, there is a very tiny chance you may still be partially right about gravitons (though it's not your fault
Disclaimer: IANAP but I do know a thing or two about physics (if there is a physicist here and I've made a mistake in my post please feel free to correct me, though I'm fairly certain the contents are accurate).
- "Hear that?! The percolations are imminent! Cease your ingress!"
I've got to thinking about this more tonight. I think this idea holds more water then I thought. Let me further explain. Because matter is the minority substance in space, it will be space that is trying to displace matter. Hence forth, gravity is a push and not a pull. But, what happens when you have two solid objects floating in space? Eventually, they will move toward each other because now the amount of space between the two objects is superseded by the increase in combined proportional mass relative to the two objects (however, the space on other side of both objects is now the majority). So the closer two objects in space are, an exponential increase in attraction (rather, being pushed together) will occur.
But, what if the space between these two objects supersedes the over all proportional mass relative to each other? If this model is correct, they will now be pushed AWAY from each other. Maybe, this is why galaxies are moving farther away from each other. You see, the space between galaxies far supersedes the proportion of displacement of space due to the mass of the galaxies in relation to each other.
I really don't have any better way to word this. I'm sure this is a very confusing to read at first, so you might have to read it a few time.
Life is not for the lazy.
When physicists speak of unifying the fundamental forces of nature, they (we) don't mean that nuclear physics is the same thing as electromagnetism, really, or that gravity waves are the same as light waves. It's more like saying that all of the fundamental forces we know of are facets of one "superforce", or that the various physical laws we've learned all make sense as consequences of a set of simpler, over-arching laws. Physicists would say that at very high energies, the differences between the various forces melt away and the overall "superforce" behavior can be seen. It's a little like the old story about blind men - we've spent our time understanding the seemingly unrelated behaviors of parts (trunks, tails, ears, and feet), and then begin to realize that we should really be studying the behavior of a previously unknown whole (an elephant). This doesn't mean we've explained the trunk in terms of the ears, but both as small facets of the whole.