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New Theory of Gravity Decouples Space & Time
eldavojohn writes "Petr Horava, a physicist at the University of California in Berkeley, has a new theory about gravity and spacetime. At high energies, it actually snips any ties between space and time, yet at low energies devolves to equivalence with the theory of General Relativity, which binds them together. The theory is gaining popularity with physicists because it fits some observations better than Einstein's or Newton's solutions. It better predicts the movement of the planets (in an idealized case) and has a potential to create the illusion of dark matter. Another physicist calculated that under Horava Gravity, our universe would experience not a Big Bang but a Big Bounce — and the new theory reproduces the ripples from such an event in a way that matches measurements of the cosmic microwave background."
Behold, science.
The catch is, eventually one will be right, and explain things that are out of the scope of Einstein's theories or more accurately explain in-scope things.
Or do you believe we are at the pinnacle of the field, and can achieve no more?
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
We have reached enlightenment. We shall now call ourselves Q.
(huuummmm)
Man this is dull.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Does this theory suck or is there some pull to it? It just seems so weighty to me.
Help save the critically endangered Blue Iguana
I believe they will all be right, but it will only be from the perspective of the observer/believer which is right at the moment. However when it isn't being observed it will be both right and wrong until observed again. Therefore there are multiple pinnacles and it won't matter which are right or highest. Just have your towel ready because on top of the pinnacle is a little man who is only going to apologize for the inconvenience.
Always have a towell ready.
*Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
Whether it's a feature or a bug depends on whether it reflects reality.
It's strange to me that Dvali would abandon his model for allowing FTL propagation of information unless he experimentally checked the conditions in question to see if information really could propagate FTL in those cases. I have to assume he did not - lacking clarification on the matter I'm left to assume that the conditions were not something simple he could test no a whim.
Without the experimental results, it's meaningless to call such an artifact in the model "good" or "bad".
To differentiate myself from the lot of you bores I shall take a first name: Fah. From this point on I am Fah Q! :)
We have always been at war with Eurasia!
If you reverse the polarity, inject some chroniton particles, and rub Patrick Stewart's head for good luck, it'll still work.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
... until they plugged the ansatz into the Horava’s action to produce the reduced Lagrangian.
Huh. I didn't get that far. And I'm pretty sure that whatever it that is, it's illegal in Texas.
BTW, my physics is really rusty, doesn't one of Einstein's equations devolve into a newtonian equation at slow speed?
Wouldn't be correct if it didn't. Newton wasn't *wrong*, he just didn't specify the parts he couldn't see. Same with Einstein, same with this.
I have to assume he did not - lacking clarification on the matter I'm left to assume that the conditions were not something simple he could test no a whim.
Wow. Anyone else see that? From my location, the n arrived before the o; however, the parent clearly typed them in order (o before n) in our reference frame, so I think we've just witnessed information traveling faster than light! Woohoo!
Actually, HE DID!
He added the cosmological constant to his general theory of relativity, because if he followed his models...it indicated that the universe was expanding.
Einstein didn't like the idea that it was expanding(because it didn't fit the current thinking), so he added the cosmological constant to his equations to make the universe "static".
so, even Einstein fell prey to conventional wisdom and thinking.
Wrong.
Special relativity is built on two principles:
(actually, if you take Maxwell's equation into account, the first is just a special case of the second). Especially it does not postulate that there's nothing faster than light. Rather,
However, you can describe hypothetical faster-than-light particles in SRT (so-called tachyons; those cannot be decelerated to below the speed of light), and AFAIK there have been experiments to look for them. Note however that as soon as you add quantum mechanics to the picture, even with tachyons no information can be transmitted faster than light (local disturbances in he quantum tachyon field only propagate with light speed).
General relativity adds the equivalence principle (locally you cannot distinguish between gravitation and acceleration) and the demand of general covariance (the equations must look the same regardless of choice of coordinates, even if those don't correspond to an inertial system).
The Tao of math: The numbers you can count are not the real numbers.
Then I shall be Fah Q 2!
.evom ton seod gis eht
Well Fah Q both then
Cousin to Sofa King Awesome, I suppose. You people are so immature.
Then we need a new theory.
Well, "the same in all systems" in the post above didn't refer to "at different places in the universe", but "as seen/described by different observers in the same part of the universe".
That doesn't mean we don't also assume that the laws of nature are always and everywhere the same. Indeed, that's basically always assumed.
By applying the laws we found locally to observations of distant objects, and seeing if they fit. For example, we can look at the spectra of distant stars and look if we get the same atomic spectral lines as on earth. This works great; so we know that atomic physics obviously works the same in distant stars. Also we can observe the 21cm hydrogen line everywhere in space, so atomic physics seems to apply also in between the stars.
Where we do have some problems is with large scale gravitation (what we describe with dark matter and dark energy). However, the local effects of those deviations are small enough that we couldn't measure them directly anyway, so it's also no evidence that the local laws of physics are different than the distant ones, even if those effects are to be described with modified theories.
No, it's much too small for that. To be an indication for different physics "outside" it would have to be such a large deviation that we would have to have detected the difference if it applied to Earth.
The Tao of math: The numbers you can count are not the real numbers.
I'm not familiar with this Jesus theory. Because I am open to outside-the-box thinking, I am willing to give you the benefit of the doubt and evaluate your theory based on it's merits, rather than dismissing it out of hand. Can you send me an example where Jesus accurately predicts known experimental results? Also, what experiments would you posit to prove or disprove Jesus? I eagerly await your reply.