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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."
Special relativity, of course, forbids sending information faster than light. A theory supplanting the space-time unification of General Relativity would also supplant special relativity, and hence might not have that limitation. Here's an inteersting tidbit from the article: "Gia Dvali, a quantum gravity expert at CERN, remains cautious. A few years ago he tried a similar trick, breaking apart space and time in an attempt to explain dark energy. But he abandoned his model because it allowed information to be communicated faster than the speed of light."
I'd call that a feature, not a bug!
http://www.geoffreylandis.com
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
Horavec's formulation works for certain (perfectly spherical) cases of the stress-energy tensor, not in other cases. In fact it produces some wildly inaccurate results in more realistic cases. Nor is he the first to try this kind of thing. Still, it sounds interesting and further refinements could produce a fully consistent theory which can match observation. When and if that happens then it will be a really major advance. It certainly seems like we're edging closer to something.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
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
... in a presentation from the 30th Workshop on Gravitation and Numerical Relativity at Jungwon University. It's a PDF version of a PowerPoint deck, so it's not exactly easy to read.
So does this compete with string theory or have a chance modifying it to an eventual theory of everything?
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!
http://arxiv.org/abs/0901.3775 PS Slashdot has the slowest comment preview of any website I know.
it fits some observations better than Einstein's or Newton's solutions. It better predicts the movement of the planets (in an idealized case)
Oh. In an idealized case. Imaginary physics. Of course, in the actual case, it does not (it requires patching to allow for non-spherical planets).
At any rate, there are at present no known relativistic measurements that are not consistent with General Relativity, so I am not clear where the "better than" comes from.
And, from the standpoint of a General Relativist, the stubborn desire of the particle physicists to have a flat spacetime at high enough energies, no matter what, seems, well, quaint.
Yeah: http://yfrog.com/b9sciencevsfaithbigp
This sentiment is rather old, I'm sure before and when Einstein came about, people were saying the same thing about Newtonian physics. Skepticism about new theories are fine, but I'm sure the science will come to a point where we do discover something better than Einstein's formulas in some areas.
BTW, my physics is really rusty, doesn't one of Einstein's equations devolve into a newtonian equation at slow speed? Which just shows that things are truly built on top of one another.
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!
1. Gravity is still spooky action at a distance with no causal mechanism defined.
2. I don't think time, as in "time lines" or some kind of unidirectional movement through a medium exists. Now exists, hypostatized out of a past (which stops existing when it stops being now) and which in turn hypostatizes the future (which does not exist.)
3. Electromagnetism is the dominant force in the heavens as it is on Earth.
4. Stars are organisms and they reproduce through fission.
5. Galaxies are powered by vast electric circuits; beads on a string.
When a true genius appears, you can know him by this sign: that all the dunces are in a confederacy against him.
Sounds to me like this is just an hypothesis as there doesn't appear to much experimental evidence supporting it. This is an extraordinary claim and so need extraordinary proof.
And, the interchanging of hypothesis and theory by scientific magazines is a bad thing. If scientists, science fans, and science writers do not use the words correctly how are we to defend the difference when creationists come around misusing the words?
There is no "-1 offended" or "-1 you don't agree with me" mod options for a reason.
Yet, who is Petr Hoava? He maintains a Web page that offers the following biography.
"Petr Horava received his Ph.D. in 1991 at the Institute of Physics of the Czech Academy of Sciences in Prague. He was awarded the Robert McCormick Research Fellowship at the Enrico Fermi Institute at the University of Chicago, worked as a Research Associate at Princeton University, and won a Sherman Fairchild Senior Research Fellowship at Caltech, before joining the New High Energy Theory Center at Rutgers University in 2000 as an Associate Professor. In 1997, he was awarded the Junior Prize of the Czech Learned Society, and in 1999 he appeared on the list of top three scientists of the Czech Republic of the 90's. He joined the Physics Department at UC Berkeley in 2001."
The liberation of Eastern Europe in 1989 has unleashed an intellectual force that will advance human knowledge by leaps and bounds. 2009 is the 20th anniversary of that liberation.
Buddha bless the Eastern Europeans.
This is healthy. Science can only progress if we accept that thinking outside the box is admissable. If the idea works ehen it will be testable.
Facts are history now plebs have politics for religion on social media.
Sounds like this guy's saying "Let us assume the speed of light is not necessarily the fastest anything can travel. If we assume this, then..."
The reason for Einstein's initial assumption is that we have never to date observed anything which has moved faster than light. Then again, would we know such a thing if we observed it, and have we actively looked for such a thing? If so, how have we looked?
It took me long enough to get my head around the intertwining of space and time in relativity. Now you're telling me that they might also be decoupled in special circumstances.
Ow! My brain hurts.
You fixed it by misspelling General Relativity?
Or maybe you actually meant the theory would be better than 'Reletivity'. That could work.
http://www.chaotickingdoms.com
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 read that some of the theory used math from helium super-fluids.
As I'm no math nerd, perhaps someone who is can explain why infinity is disallowed? I finally figured out why you can't divide by zero; 10/2=5, 5/2=2.5, but if you use numbers smaller than one it is reversed; 1/.5=2, 1/.05=20, so anything divided by zero would be infinity. Is the universe infinite? If so, how can it be studied mathematically?
I found this intrigueing:
I'm no physicist, but that occurred to me when I first herd of the big band theory. If so, would it bounce an infinite number of times?
Free Martian Whores!
There are really 42 quarks.The LHC should probably be able to test this...
(God but I love that guy's cartoons!)
Free Martian Whores!
Yep. It's called the Correspondence Principle when applied to quantum/classical mechanics. Basically, Newton's equations 'fall out' of Einstein's when you assume the speed of light is a big number relative to all other speeds.
Recently, paradigms in physics have been interesting in this respect as the new perfectly subsume the prior in their limits. I am not sure that this is a tautology of science, but it is an elegant means of progression.
In one day, and they are both in California. I am stuck here in New Jersey. New Jersey is Hell. When people die, they don't go under the ground, they just pop up somewhere in Newark. See, us citizens of New Jersey are immortal because if we are killed, we just pop up back again in New Jersey. Its just really hard to navigate around Newark, so that's why you don't see us again..................
i am so very tired....
I'm really going to destroy my karma here, but I think that diagram isn't correct. I would argue that personal faith is almost identical to the path of the science in the diagram. There are those of us out there who hold beliefs but aren't afraid that our beliefs might be changed by what evidence we are presented with. Faith will always be there for the things we do not have the tools to understand. Whether or not you apply a god to it doesn't matter, because in the end, past what our science is able to tell us, everything comes down to a belief.
The problem with faith is when it becomes blind faith. Some people think what they've found is the be all end all and refuse to search anymore. It's not specific to the religious either. If you notice, there are "science" folk in here mocking this new theory because it contradicts the old one. Think about this next time you want to take a swing at someone who holds faith.
My hypothesis about gravity:
Everything is growing. We can't see anything growing, because our rulers and tapemesures and everything is growing. That's gravity: Just the growing earth pushing against your growing feet. Gravity at a distance is just objects growing towards each others (the void doesn't grow). Come to think of it. It's probably a bad hypothesis. It couldn't explain a slingshot effect, could it? Nevermind.
Some of my favourite people are from th US; Vonnegut, Chomsky, Bill Hicks.
But does it also predict that time is an illusion, lunch-time doubly so? If not then there is still room for a more refined theory.
Then I shall be Fah Q 2!
.evom ton seod gis eht
Same thing in Quantum Mechanics. They devolve into classical equations, if you set Planck's Constant to 0.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
The problem isn't so much with the infinities, those are perfectly allowable in math and in physics.
The gravitational pull as you approach a black hole approaches infinity
The limit of the graph 1/x as x->0 is infinite.
The problem is that other theories of quantum gravity result in infinities where we do NOT observe these infinities to exist. As a simple example (quantum mechanics is beyond me, but this gives the flavor), one of the classic theories of electrostatics states that the electric field of a point charge is inversely proportionate to the square of the distance from that charge.
However, from a quantum-mechanical standpoint, and electron has no size...it is a point particle.
This causes an issue if we take both of these results together...as you approach an electron, the electric field should approach infinity.
We know that this doesn't happen, so one of the two theories must be incomplete.
Well Fah Q both then
Cousin to Sofa King Awesome, I suppose. You people are so immature.
I don't understand this, I don't need faith to believe there is order in the universe. It's been proven that there is a certain amount of order and I can reproduce those measurements if I wanted to see for myself. Causality is equally provable. We don't know how everything works yet but the stuff we are sure about I don't need faith to believe. The other stuff we make our best guess while reserving the right to change our mind pending further data.
Yes, with science there is a certain amount of established expectation based on observation. Do something, see what happens, expect it to behave the same way in an identical situation. If it doesn't behave the same way, figure out what's not identical about the situation. I don't think it's right to call this faith, or if you want to, it's important to suggest the only REAL faith is "expecting what you've already observed will continue to be true". There are still tests that can be tried and repeated, there are generally equations that can be applied to the results.
Religious faith, on the other hand, deals with having insight into the unknowable. As such there aren't any tests, any results, no expectation of repetition, no equations.
Religious faith may be rewarding for many people in many ways (hey, it seems pretty popular), but it doesn't pay to confuse it with the scientific process. Those two different uses of the word faith are so divergent, it's probably better just not to use them.
The Quirkz Handbook of Self-Improvement for People Who Are Already Pretty Okay
Spooky action at a distance doesn't need any finagling to get around lightspeed, because spooky action at a distance doesn't involve any communication. It's already compatible with general relativity (at least, insofar as any quantum theory is compatible with relativity).
A flawed, but illustrative example that should explain why this is so: imagine you have a friend who is flipping a coin... if it comes up heads, he writes an X on two sheets of paper, if it comes up tails, he writes a checkmark on both instead. Both are immediately sealed inside envelopes and mailed to opposites sides of the planet. If you open one letter and see an X, you instantly know the other has an X also. That doesn't require any communication.
A slightly less flawed, and still illustrative extension: Now instead of a coin flip, you have a machine do it based on the decay of a mass of cesium, and you have a perfect envelope which protects against quantum decoherence. The same situation applies, as soon as you open one envelope you know what is contained in the other. The only difference this time is that the letters were entangled and in a superposition of states. However, it's the same mechanism, and no communication is required.
All faith is blind.
'Faith - Belief that does not rest on logical proof or material evidence.'
And just because some may swing one way or the other within either group doesn't show anything. At its root religions are unchanging, or at least the Judeo-Christian ones are meant to be. At sciences base we strive for changing, evolving viewpoints.
No, that is a stupid terrible meme. First off the axioms of science are things like 'a + b = b + a', compared to there is a God and history as described in a multiple 1000page book. Not the % of which is axiom, In fact the whole christian belief system IS a huge axiom, individuals get to add theories on top that's all.
As well, science is made of 'best guesses so far'. That 'so far' stipulation means you don't actually have faith in anything merely knowledge of a best guess. Scientists/Philosophers haven't proven with any great certainty that we can know anything so all we CAN do is make guesses. The only absolute proofs we make do use givens, so we can prove things withing certain constructs. Like, we can PROVE things in math, but it is an artificial device. That isn't the same as universal truths. All we get there are good guesses.
Do we act on those guesses? Certainly, much like you'd call a friend's cell before his house. You don't KNOW he is there, simply that is the best educated guess you can make at the moment. The idea that people EVER need to make a leap of faith is total BS.
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.
Not so. You cannot prove that repeatedly making a measurement in the past is any indication that it will hold in the future. Pointing out that it's worked before is just begging the question, and therefore reproducing the results doesn't help, for it does not mean you'll reproduce the results *again*.
You *must* presuppose that the future is relevantly like the past for empiricism to have any meaning in any context; it's pretty much an irreducible problem.
With that said, such "faith" is, I would argue, essentially to daily living and doesn't really deserve to be categorized as "faith" except in the most pedantic of senses. Without acting under this presupposition, you cannot learn. Anything. I suspect that biologically this presupposition cannot be unlearned since it appears to be intrinsic to learning even in some of the stupider members of the animal kingdom.
Faith is belief in something for which there is no proof or even strong evidence. Faith is generally applied only to spirituality, and it should be so according to the definition. For example, I don't need faith to believe that the Yankees won the World Series this year - there IS evidence for that. I do believe that they won BECAUSE of the evidence.
You do NOT need faith to believe that the universe is anything. Ordered, structured, causal, etc. A good scientist believes these things because there is evidence of order, causality, etc.
To not have faith is to not believe in something for which there is no evidence.
One does not need faith to look forward to the future doing something chaotic because of the belief (through prior observation) that those kind of things (earth turning into a carnivore butterfly) just does not happen.
Science and faith are NOT intrinsically linked. Science and belief ARE. Science and faith are two completely separate things.
No one is questioning the intelligence of the soviets or eastern europeans. The problem was that when they did science, they did it in an inverted way. For example, in Soviet Russia, the particles accelerated you.
Fah Q and the horse you rode in on?
"You cannot prove that repeatedly making a measurement in the past is any indication that it will hold in the future."
Flip side, you can't prove that it won't hold true in the future either. In essence, your argument is a case of argumentum ad ignorantiam.
The bottom line is that you're engaging in fancy footwork trying to get to him to use the word "faith", in which case you then have a basis for moving on to a discussion of "true faith", a belief in God or some such. Faith is belief without proof.
But... if you have proof then you don't need faith. Past personal observation, history, science, math, and orbital mechanics all say that the sun will come up tomorrow. Faith is not needed.
Any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so.
Yes, and our current problem in physics is that we have two forks of Newtonian Physics. In one branch, we fixed the description of gravitation, in the other branch we fixed the description of subatomic particles. Both branches are very successful in their respective area. Now we try to merge those branches, however it turns out that the patches are not compatible, and we don't know what is the right way to combine them.
The Tao of math: The numbers you can count are not the real numbers.
There are two stated assumptions in the principa, one of them is that "time is constant", 20/20 hindsight says this assumption was wrong. However, the fact that he had the insight to recognise that statement was an assumption is testement to his genius.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
"Faith is belief without proof."
Belief without evidence is called blind faith, science rests on the faith that the universe is ultimately predictable and will continue to exist even if we don't (in other words it believes that the proverbial tree in a forest does indeed make a noise).
There is no way to "prove" that the universe behaves like this but rational people take it as an indisputable fact because the evidence of ones own perceptions is very difficult to ignore particularly when they match the perceptions of other humans. So yes, science is based on faith as is all knowledge that goes further than "I think therfore I am".
"The bottom line is that you're engaging in fancy footwork trying to get to him to use the word "faith"
No he is not, the "bottom line" is that basic scientific philosophy confuses the hell out of people who subscribe to the popular but incorrect notion that science is in the bussiness of "proof". We wouldn't even be having this discussion if epistemology was taught in modern high schools.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Haven't we proven enough of our theories about this world that we know for certain things are stable to a known degree?
Not to be contrarian, but we haven't proven any of our theories at all.
First, you do not know what is occurring in every place in the universe. No number of experiments will ever prove a theory to be true because you cannot perform the test at every conceivable place in the universe. This is why Francis Bacon stated that the proper scientific method should be falsification. You only have to find one place where a theory comes up short to prove it wrong, but time constraints say that you can never prove that it is right. This is what modern science is based upon.
More importantly to his post, however, is the fact that we have no deductive reason to assume that the future will replicate the past. The GP says
Pointing out that it's worked before is just begging the question
He is referring to the problem of induction http://en.wikipedia.org/wiki/Problem_of_induction
This is not "fancy footwork," it is a many centuries old philosophical problem brought up by David Hume. You cannot state "X happened in the past, therefor it will happen in the future" without using "X happened in the past" as your reason for believing "X will continue to happen."
Essentially, you cannot prove induction correct without being inductive. "The ice I've touched has been cold, therefor all ice is cold" is not deductive reasoning.
This is, for all intents and purposes, a genuine criticism of the scientific method. "All ice I've ever touched is cold" may be true, but "All ice is cold" is completely false. http://arstechnica.com/science/news/2007/03/turing-water-into-very-hot-ice-very-very-quickly.ars http://uk.reuters.com/article/idUKN1621607620070516
This is the sort of thinking that science employs, however. Now, his point is not that science is not useful, nor is it that science is wrong. He is simply stating that inductive thinking is programmed into us, and that there is no good deductive logic which led us to it. You see neither causality nor time, these concepts exist inside of you -- i.e. Science is a byproduct of being an ape, not a byproduct of logic itself.
It's always interesting how quick some people without deeper knowledge of the matter are with labeling something as nonsense.
I have 3 dark PhD's, and I say it's bunk!
You're thinking small. Why miniaturize the laser, when we could instead enlarge the sharks? -John Searle
Can you send me an example where Jesus accurately predicts known experimental results?
(I'm not sure if your stay on rejection was genuine or troll-bait, but it's caught momentum and I thought I'd provide an honest response rather than leave the question hanging.)
There's the golden rule, for starters. He didn't invent it, but he was instrumental in the widespread use of its positive statement ("Do unto others as you would have them do unto you" as opposed to "Do not to your neighbor what you would take ill from him"). And the result of following that rule, the rule of initiating kindness, you are statistically more likely to be treated kindly in return. Common sense and anecdotal evidence bear this out as well.
Then there's a bunch of other stuff he said, including things about the Kingdom of Heaven being here and now, forgiveness, faith, and love, that has unfortunately been so steadily downplayed and cloaked in tradition and dogma that it gets lost in the "war" to "win souls" for God. I think the historical Jesus would get along just fine with good-hearted atheists, Muslims, Hindus, Krishnas, Christians, Buddhists, and followers of most any other creed that you can imagine--and he probably had more in common with the Buddhists than we tend to think. He might not agree with all of the beliefs in those various systems, but he was more interested in disciples, people who would emulate his way of living, than converts to his religion, which didn't even exist during his lifetime. In other words, I think he'd be an excellent person to discuss philosophy and religion with, and he'd probably be the first to quell any budding flame wars.
This is of course only my understanding of Jesus. I've put a lot of thought and a decent amount of study into it, so I have a nuanced view not shared by most Christians, but I prefer to simply act in a manner I think he would approve of than to talk about it. It's more challenging and more effective to act, and I lack the agenda to convert people so dislike being perceived as having it. It is still disheartening to see his teachings rejected out-of-hand because of the centuries of stupid, un-Christlike actions of his followers, not to mention the (in my opinion) corruption of his words within the Bible. I hope to change that by trying to live up to the way I think he did. Even if most people who learn from me never find out my source, it is a good way to live.
Your brain is not a computer.