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Relativity Finally Meets Quantum Theory?
prion86 writes "Physisist Fotini Markopoulou Kalamara (try saying that 3 times fast) believes she has found a way to blend relativity with quantum theory. The article can be found on the Scientific American site."
She talks about physics like it's cooking. If it turns out she's right, a whole new generation of scientist will grow up thinking that women are only good with kitchen-related things. If it turns out she's not, then, it's just a flash in the pan. Insert moronic sexist joke here. (I hope she's right though, it's about time that somebody found something significant, to finally have another woman's name in physics books).
The ENIAC Demo Competition
The physicists who can make stuff like this comprehensible to laymen like me (like Stephen Hawkings) are the ones that really deserve a Nobel prize.
but how will this help me with getting laid
It'll help with that special physisist of your dreams you've had your eye on, of course! Great conversation peice.
Just like to point out that what she's doing is combining relativistic gravitation with quantum physics to produce the physicist's holy grail - quantum gravity.
Merely mixing relativity and quantum theory has been done for years and years - the form of the strong nuclear force was found by Yukawa to be a solution of the Klein-Gordon equation - which was proposed in 1924. The relativity papers were published in 1905, 1908.
OK, so I haven't actually clarified anything at all, have I?
Am I the only one that found some of the article's tone, and the cooking analogies, a bit sexist? I don't think the oven stuff at the end would have made it into the article if this work was being done by a man.
As a student of physics, this is still a bit beyond me, but I'll be there soon. Things like this pop up occasionally -- most disappear. The theory has to make predictions that can be tested and verified. Just getting QM and gravity together mathematically is not enough.
Tim
-- Hello_World.c: 17 Errors, 31 Warnings
this sort of thinking has its uses and indeed is in use everyday. However, won't a lot of it be pre-empted when cold fusion comes out from underground? After all, Mitsubishi heavy industries, among others, is doing cold fusion right now, thanks to the politicization of research in the US.
C|N>K
"Having fun is essential, because otherwise you get stressed out. You think, I have to show the universe is made out of atoms, and aaaaahhh, you flip out! So you want to keep loose."
One experiment could be to track gamma-ray photons from billions of light-years away. If spacetime is in fact discrete, then individual photons should travel at slightly different speeds, depending on their wavelength
Well thats the trick to solve problems like this. I wanted to put in layman's terms why this is a problem. I don't understand why this is such a big deal. I understand its cool and exiting but people have come up with theories to solve this problem all the time for years. Its another cool one with all sorts of other cool things it could mean but even if its proven on paper you still gotta test it.
unzip; strip; touch; finger; mount; fsck; more; yes; unmount; sleep
From the article:
She talks about physics like it's cooking. (at the beginning), and In the meantime, she's hard at work, and waiting for the oven bell. (at the end).
Why are women always associated with cooking? Maybe she does cook well but that's not the point of the article... so why open and close it with that?
Definitely hypersensitive.
Not every attempt at humor is a slur. And shame on the moderator for marking this comment at all.
Insightful my ass. The poster obviously thought this was important or wouldn't have posted it. Why would they do such a thing AND make a 'racist' comment about the person they are evangelizing?
Get a grip and then go get a life.
Anyways, back to real commentary.....
A fool throws a stone into a well and a thousand sages can not remove it.
Physisist Fotini Markopoulou Kalamara (try saying that 3 times fast)...
Try saying "physicist" once, and slowly.
Lisp is the Tengwar of programming languages.
but when was the last time any of us has seen a woman, let alone a woman that looks like that in our physics departments? I don't know about the rest of your schools, but my University's Math and Physics departments are completely devoid of females both on the student and faculty level. I think something like this could finally tell that majority of women that feel that they just can't do stuff like that, that in fact, they can, and that they can do it well.
:) and then stated that she works in the Physics field with QM and Relativity? I know I would be.
Honestly, how many of you would not be totally stuned if a girl looking like that introduced herself to you (first big surprise
"It's a beautiful thought: we each have our own universe. But there's a lot of overlap. "We mostly see the same thing," Markopoulou Kalamara explains, and that is why we see a smooth universe despite a quantized spacetime."
Personally I like this version of unified relativity but I'm very certain that there will be many nay-sayers concerning her metaphysical POV of light cones and spin networks as personal and individual interpretations of the universe... though it is really nice to hear a published physicist speak about overlapping collective conciousness and the impact on perceived physics of the universe.
A fool throws a stone into a well and a thousand sages can not remove it.
I may still be a plain old physics student, but even I know that using the standard interpretation of quantum mechanics, as she appears to, to create an entire cosmology, is very problematic. The standard interpretation is beset by massive difficulties in the form of the measurement problem, and most other intepretations are far more successful in dealing with this. The Everett interpretation (sometimes referred to as the 'Many-Worlds' interpretation, although this ascription is inaccurate in several ways) is the one most commonly used by quantum cosmologists, and with good reason, as it does actually allow for a quantum state vector to be applied to the universe. The standard intepretation, however, does not allow for such an assignation, it is nonsensical to talk about it in the standard interpretation, a point which seems lost on the writer and perhaps even the obviously very intelligent physicist. Maybe they both should have attended philosophy of physics 101.
Forgive me, oh vengeful modders-down, but...
Every up-and-coming physicist and his brother has a "theory" of quantum gravity.
Note I said "his". What ratio of physisists do you suppose have two "X" chromosomes?
So why did *this* theory make it to the increasingly (and disconcertingly politically correct) Sci-Am?
You already have the answer, from what I wrote above.
To put it bluntly, this wouldn't have gotten a second look from someone's dissertation advisor if "she" had 'nads.
Note that I do NOT mean this to say a female can't do physics - I only mean to say it only got published in such a high profile magazine because of her gender, not on its own merits. Sad, really. I used to like, Sci-Am, once upon a time. Long ago, I even switched from the somewhat flakier "Discover". Looks like I'll need to go to just plain vanilla "Science", along with its HUGE pricetag, if I want to continue getting reasonably unbiased and non PC-censored news from the world of science.
There's one thing I don't get. Here's the relevant snippet:
But a spin network represents the entire universe, and that creates a big problem. According to the standard interpretation of quantum mechanics, things remain in a limbo of probability until an observer perceives them. But no lonely observer can find himself beyond the bounds of the universe staring back. How, then, can the universe exist? "That's a whole sticky thing," Markopoulou Kalamara says. "Who looks at the universe?" For her, the answer is: we do. The universe contains its own observers on the inside, represented as nodes in the network. Her idea is that to paint the big picture, you don't need one painter; many will do. Specifically, she realized that the same light cones she had used to bring causal structure into quantum spacetime could concretely define each observer's perspective.
Because the speed of light is finite, you can see only a limited slice of the universe. Your position in spacetime is unique, so your slice is slightly different from everyone else's. Although there is no external observer who has access to all the information out there, we can still construct a meaningful portrait of the universe based on the partial information we each receive. It's a beautiful thought: we each have our own universe. But there's a lot of overlap. "We mostly see the same thing," Markopoulou Kalamara explains, and that is why we see a smooth universe despite a quantized spacetime.
So my boggle is this: Until the first "observer" evolved, nothing observed the universe, so it existed in all quantum states simultaneously. If so, how did that first observer ever evolve? Or is she posutlating that the universe's existence is its own observation?
... is whot bwings os tugevza tsuzay.
This would seem to indicate that if we looked out far enough into space, we would see nothing. We've yet to find any boundary. When will we? When I was about 10 years old... I remember reading on the side of my McDonalds Happy Meal box that we'd see the "edge" of the universe within the decade. Why haven't we found it yet?
Sex - Find It
So, either we're just probably reading Slashdot or there is a God. Pick one.
Money for nothing, pix for free
http://arxiv.org/abs/gr-qc/0203036 for those of you that have advanced degrees in physics... could the rest of us have a translation? Of course I could be off with the publication, but it is hers and it's the only one Perimeter Institute had for her, and the introduction implies gravity with quantum physics... just a disclaimer. I don't have that advanced physics degree yet.
Well.. we had relativity (which has been beyond us mortals), we had quantum mechanics ( whic again has been beyond us mortals) and now we have quantum relativity (and guess what ! they all are STILL beyond us). Now what? Humans have this notion that they are gonna solve the mystery of life.. which they may someday.. but not for the next few centuries (unless we have vulcans landing up on earth a-la star trek). When we discovered the atom we thought we had all the answers.. and NOW we say if we crack quantum mechanics.. we are gonna have it all. Hm.. maybe if I understoof what this lady was saying, it would help.. but.... wooooooshh.. over my head
|/________
|\A|ALYS|
The real point to the whole article is that she's a hot chick. There's lot's of speculative ideas floating around about how to resolve the differences between relativity and quantum Mechanics. The discussion has been running since the twenties.
She may well have some contribution to make, but that's not how you get your picture in a magazine. You get your picture in a magazine by looking good. I used to work as a TV cameraman, and we always interviewed the hottest chicks we could find. Why not? They have opinions too. And they draw audiences, thus spreading the word.
"A spoonful of sugar helps the medicine go down / In the most delightful way" as Mary Poppins put it.
So sexist remarks are very appropriate. Pile'm on.
I bragged about my Karma at a job interview but I didn't get the job.
Everyone who's whining about the line "she talks about physics like it's cooking," should shut their pie holes. The reason that line is in there is not because the writer is sexist, it's because she DOES talk about physics like it's cooking ("to take this ingredient and another one there and stick something together").
...can be found in the arXiv database. A search for Fotini gives ten results between 1997 and 2002, most of them published in well-known journals, such as Phys. Rev. D, Nucl. Phys. B etc. Not that I understand any of it, by the way...
From the article:
Each spin network resembles a snapshot, a frozen moment in the universe. Off paper, the spin networks evolve and change based on simple mathematical rules and become bigger and more complex, eventually developing into the large-scale space we inhabit.
Is it just me or does this look a lot like what Wolfram suggested in "A new kind of science"?
This reminds me of a theory put forth by Stephen Wolfram in "A New Kind of Science" (or, possibly from someone else earlier). Imagine that the universe was actually a huge cellular automota, where every concievable location in space-time is a cell. If you start drawing lines between these cells, you get a network which is perhaps similar to the system described by the article.
What is interesting is that this can explain the "light cone" phenomenon as well. If we are given that a cell can only be affected by those cells adjacent to it in the network, there is a theoretical fastest response of a system, depending how often the "steps" of the automota occur, and how far reaching are these network edges. For example, if we had two nodes 3 edges away from each other in this great graph, it would take at least 3 "ticks" for either cell to affect the other. Perhaps this is the concept she's using, but with actual physical concepts instead of some abstract idea of cells?
So there I was, juggling apples and small animals, when I accidentally bit into the wrong one...
Now that's funny... ! ;-j
A fool throws a stone into a well and a thousand sages can not remove it.
If it turns out she's right, a whole new generation of scientist will grow up thinking that women are only good with kitchen-related things
only ignorant people think so even today.
STW for Emma Noether's and Lisa Mitner's stories.
(Lisa Mitner was like an underdog^2 : both a jewish and a woman
in the pre-Nazi regime. So off the Nobel went to who was very
probably the less-deserving coleague)
Working for necessity's mother.
Some of the players in loop quantum gravity (LQG) before Kalamara are Abhay Ashtekar, Lee Smolin, Carlo Rovelli, John Baez and Chris Isham. Also, Julian Barbour has written a cute semi-popular book called The End of Time on the subject as has Lee Smolin---Three Roads to Quantum Gravity
Anand Rangarajan anand@cise.ufl.edu
You never know.
- A.P.
"Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
It bugs me when these physicists get all postmodern about their work and call it art. What they do is organize phenomenalogical data into commessurable patterns. They then mess around with seemingly conflicting patterns in weird combinations to see if they can get 'fundamental' patterns. They do this over and over again. She probably means that advancing physics requires a willingness to break the rules, think differently, color outside the lines... etc. The the degree to which physics posesses that quality pales in comparison to the classical definition of art I suppose the process of physics does require creativity, but physics is an overwhelmingly destructive context for ideas.
Really, this is just PR for L.Q.G, not that I'm knocking that - string theory attempts to solve similar problems (quantum gravity) and although it is in a much more advanced state of understanding (hundreds if not thousands of physicists have been working on it for 20 odd years) it is still completely hypothetical without a shred of experimental evidence and yet, if you listen to the popular science guys, that's quite often put in the small print - giving the impression that string theory is accepted fact. Giving some popular airtime to some of it's (admittedly few) rivals can only be a good thing.
Struggling to find a day everyone can make? WhenShallWe.com
I suspect people haven't yet forgiven him for creating the Daleks.
you are either getting laid or you are not, with an equal probability.
You can't just assume that the two states have equal probability. If you are in thermal equilibrium the probability will be given by the Boltzmann distribution meaning that the probability of "getting laid" falls of exponentially with the energy of the state "getting laid".
Since people getting laid are generally described as "hot" we can conclude that the chance is pretty slim unless you do something to raise the energy of the state "not getting laid" accordingly. (Please reply with suggestions)
On the other hand, if you really are in thermal equilibrium you are dead and the result may not matter much to you.
Any sufficiently advanced libertarian utopia is indistinguishable from government.
It is important to notice that the light cones for all humans being (dead, living, and in all probability those not yet born), are not just ovrlapping, they are for all practical purposes identical, because we all live so close together (cosmologically speaking) in both time and space.
There is a sad tendency of some less honrable people at humaniora to try to tie their pet models of the weak (consensus reality, social consructionism, cultural relativism, whatever it is called this month) to physical theories like quantum physics and even Einsteins relativity theory, apparently to give them some extra credibility.
Apart from it being bad science to apply models outside their domain, these attempt are never really based on more than some shared terms, even if this usually is hidden by a flood of words.
The models humaniora are actually pretty good in their own domain, as long as one remember they are models useful for dealing with a limited range of problems, and does not attempt to interpret them as metaphysical truths.
One of the results of your suggested search was a section of a website called "Crank Dot Net."
'nuff said.
We can neither love nor pity nor forgive. If you make a slip in handling us you die!
"only ignorant people think so even today."
You say that as if ignorant people were a rarity.
BTW, what's STW?
Information doesn't want to be anthropomorphized anymore.
You say that as if ignorant people were a rarity.
.
...
ignorant _physicists_ are in my humble experience a rarity
BTW, what's STW?
Search The [F word of choice] Web w/o the F
Working for necessity's mother.
John Baez is a well-known mathematician/math. physicist who works in, among other things, quantum gravity. He is also very well known for the Usenet column This week's finds in mathematical physics, which is certainly worth a look a t if you're at all interested in these things and have a bit of a mathematics background.
One of the great things about TWFiMP is the writing style: when reading it, one really does get the idea that one understands what's going on. Of course this tends to wear off soon after leaving the computer, but. At any rate, many of the TWFiMP talk about spin networks and quantum gravity, including for example week 43 and week 55. Week 110 talks specificially about Penrose's spin networks. He mentions some of Markopoulou's work in week 99, week 114 and week 133. These might provide a bit of a middle-ground between the very fluffy SciAm article and the hard stuff on arXiv.
Of course there is also Markopoulou's recent expository article, which is a great introduction!
The only Daleks I know are described as follows: Encased in their pepperpot-shaped travel machines, each Dalek is a mutant monstrosity from the planet Skaro. They are one of the Galaxy's most fearsome races, with no thoughts other than that of conquest. The Daleks consider themselves the most superior race in the Universe. Humanity and all of the other species in the Galaxy may be permitted to live as their slaves - but that which they cannot subjugate they will destroy. Their main weaponry is the gun attached to the front of their casings. Even a glancing shot is sufficient to despatch the hapless victim in screaming agony... I doubt the Stephen Hawking invented those....
What's under yellowstone?
I'd like to see more stories like this on slashdot. It would be nice if we could spend more time contemplating real science and less time bashing microsoft.
I for one spend to much time being bitter at microsoft and not enough doing interesting things.
I wanted to compare her 'forked' String Theory but I yet to find more papers from her...hmm...
I can't help but recall a joke in which the punchline is something along the lines of: "I wanna fork on the table."
Perhaps I should get some sleep, or something.
We can neither love nor pity nor forgive. If you make a slip in handling us you die!
Damn, that was a bizzare post.
We can neither love nor pity nor forgive. If you make a slip in handling us you die!
The Observer has been there from the beginning.... but not before the beginning.
The only bone I have to pick with you is that you don't seem to understand the concept of dimensions. In the 3rd dimension, there is no such thing as "THE 2nd dimension." The second dimension is an infinite array of 1st dimensions. The 3rd an infinite array of 2nd dimensions...etc. I took a course in cosmology 3 years ago and we covered the following:
1st dimension: Length
2nd dimension: Width
3rd dimension: Depth
4th dimension: Time
Einstein's whole basis for relativity was that an even occurs at a location that is described in 4 dimensional coordinates. That event is then propogated at the speed of light throughout all four dimensions. Two different observers located at different points in space-time actually witness different versions of the event based on there RELATIVE location and velocity RELATIVE to the event.
Just to make your heads hurt, understand that 1 second is now defined as the time it takes light to travel ~3.0x10^8 meters. Since the speed of light is defined as ~3.0x10^8 m/s, the units and values cancel out to read that the speed of light is simply 1...no units. This makes the math quite easy, but is a b!7ch to rationalize in your head when you try and apply it to a real world event.
Also, the article did not say that being outside the universe would make everything clear. It said that with respect to quantum theory, the observer is genarally located outside of the space of the object that is being observed. As we presently do not know how to be located "outside" of the universe, we just have to accept that, not only can there be multiple observers, but they can also be observing from the inside of the very object they are observing. The quantum implications of this are in itself, enough to give anyone a really bad headache.
I've dirtied my hands writing poetry, for the sake of seduction; that is, for the sake of a useful cause. --Dostoevsky
The EPR 'paradox' isn't a problem at the level of physics. Quantum theory (even non-relativistic) makes very clear predictions about the statistical properties of measurements on spatially separated but correlated particles, and experiments agree. There is no violation of causality. No information propagates faster than the speed of light. Certainly the effect is weird, and it conflicts with some of our naive (i.e. non-quantum) intuitions of how to interpret a physical theory, but there is no logical contradiction and no need to extend or modify the quantum theory to account for experiment.
Wavefunction 'collapse' has some interesting details to be worked out, and some deep matters of interpretation that could use clarification, but it also to date presents no conflicts between experimental results and theoretical predictions. Wavefunctions follow the time-dependent Schrodinger equation, always. It's just when the quantum mechanics extends substantially into macroscopic systems with very large numbers of degrees of freedom, the dynamics of the many-body correlated wavefunction becomes quite complex and our regular intuitions can't keep up very well.
One thing to keep in mind is that wavefunctions do not exist, according to a reasonable definition of exist. The only thing that exists is that which can be measured, that which is physically observable, that which is accessible to an experimental observation. A wavefunction is not physically observable. It is a mathematical tool used to make predictions about experimental results. The simultaneity of collapse of a wavefunction isn't like the simultaneous collapse of say an egg carton. All physical properties related to the process of collapse of an egg carton can be measured by experiment as a function of distance across the carton: density, shear forces, stresses, shape, etc. Not so for a wavefunction.
Curtains for windows?
Damn, I think I know how the theory got started.
"Let's suppose there are a number of dimensions...for convenience, call them dimension A...dimension Z....so well then, let's assume there are 26 dimensions for now."
Gotta say it like the Prez...
There are many contenders
Loop Gravity (this article) & Spin Networks (the easiest to quantize space time with)
Noncommutative Geometry (IMO the most promising)
Stochastic Gravity (the most humble)
And I am sure that I am forgeting more. But string theory gets the most attention and the most money. This is odd to me because string theory has/had some of the ugliest assumptions (particles are strings, supersymmetry) and introduces the most extra stuff (lots of extra Kaluza-Klein style dimensions, all kinds of extendend objects, excessive parameters).
If string theory ever reaches current holy grail, then I think it will end up being a completely different theory.
A Usenet Troll Triumphs on Slashdot
In my opinion, the "observer" does not have to be sentient. To me, an observer is an outside object, animate or inanimate, that is affected by the outcome of an event between other objects.
:)
What was Heisenberg's theory? You can know position or you can know velocity, but you cannot determine both at the same time without some uncertainty. So, either your system is affected by the velocity of a wave (with light, velocity & energy dictates wavelength) or by the position (distance & mass dictates gravity).
In my opinion, this must work for gravity, because objects are interlinked over large distances, and therefore positions & mass must relate to the observer in some way, because the observing object is always drawn towards the mass. I can't think of any known formulas where velocity of an object creates a gravity well, only mass. On the flip side, because of the light refraction experiments we know that photon positions can vary within the bounds of uncertainty. But, there are many people far smarter than I who like to think about these things, so I'll leave it to them to resolve the details
There is a reason that scientific american's website is only one letter away from 'www.scam.com.'
====
Crudely Drawn Games
Is this the same Markopoulou that went tramping around Mongolia and China a few hundred years ago?
"I'm not impatient. I just hate waiting." - My Dad
Einstein and others of his ilk that expected science would continue to find simpler and simpler rules that explain how things work would be very sad.
Once we completely understand the laws of physics, I have every expectation that they will be completely incomprehensible, even to really smart people.
Just last night John Baez (mentioned several other times in this thread) announced a potentially important breakthrough: a LQG calculation that derives the same value for a fundamental parameter as one based on classical assumptions. He calls it "tooth-gnashingly nerve-wracking exciting."
The Elegant Universe by Brian Greene does a great job of explaining relativity, quantum mechanics, and how superstring theory makes them all play nicely. ISBN# 0-375-70811-1 if you're interested.
Now try to disprove it.
Disprove what? A free-energy scheme, which has managed to hire a web-designer and leech some investment capital?
A rudimentary amount of research reveals the company you refer to was founded by a Dr. Randell L. Mills in 1991, and has so far failed in all attempts to produce results... a buisiness based on exploiting the energy of the alleged "hydrino," which I doubt any reputable physicist has even HEARD of, is a rather bad idea.
We can neither love nor pity nor forgive. If you make a slip in handling us you die!
Each dimension does not have to have the common names we give it but it helps to use those names. Using the same pattern you can give names to any of the other dimensions required by String Theory. You could use any type of measurement to explain it. You could explain it as a "hue" dimension. It does not have to be this but let me explain how this works.
;)
When you have a two dimension world you plot on the x and y axis'. When you add a third dimensions you can have infinite points using in space using the same x and y coordinates.
When you add time to the third dimension it does nto change the thrid dimension at all. Two things can exist in the same place (a big no-no in physics) only if they do so in a different time.
If you want to use soem type of "hue" explaination for the fifth dimension it would work like this. You have your regular 4 dimensional world we live in, then you add one more. Now each point in time is defined by x, y, z, time, and "hue". You can have infinite space inside the same old 4 dimensions. If you never changed the "hue" rating of your existance it would be like living on a two dimension sheet in a three dimensional world.
Who knows if we really live in 4 dimensions? Im not saying we dont but there are some ways to explain why we would not have seen extra dimensions if we didn't live with em... but alas the turkey is almost done so i gotta go
happy thanksgiving
unzip; strip; touch; finger; mount; fsck; more; yes; unmount; sleep
If a male scientist looked like, say, Pierce Brosnan, don't you think he'd get a lot more pictures in the magazines, too?
I saw a special on one of those Edu-macational channels about this issue. They described an experiment where they sent two groups of people around to various job interviews, then interviewed the interviewers afterwards. One group was conventionally attractive but told to phrase replies in the simplest way possible. The other group was plain but smart, and told to be as witty as they could. When asked, the interviewers almost always claimed the better looking person sounded more intelligent.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
I know a lot of women who burn water and have to look up the recipe for ice cubes. I know a lot of men (myself included) who can make hundreds of dishes from memory. I'm a network admin and part time programmer. I think many people in the computer field have the proper mindset to make good cooks, whether they have any training or not. Recipes are so much like programs. Once you know the basic syntax and common routines of cooking, it's easy to come up with tasty recipes. I usually only look in books for highly technical recipes, like breads and such; or to get inspired by new ideas.
I guess I'm going off about cooking because it's Thanksgiving here in the States, and I'm cooking a bunch of stuff right now: Turkey, stuffing, gravy and two pies. I haven't eaten anything, to save room. The smell is driving me berserk. I practically need a damn drool cup, and it's gonna be two hours until we eat.
Turkey coma, here I come!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
er, thank you for making my point better than I did :/
C|N>K
> 4th dimension: Time
I would argue that time is only half a dimension. It only goes one way.
No, just we can only travel one way through it. (t least, at the moment)
c - a blessed +5 grain of salt
Should open-minded science and rational religion actually converge at some point, we would have great cause to celebrate. Ultimately, shouldn't they produce the same conclusions about the nature of reality? This may occur through totally different methods and vocabularies, but it should still occur.
Please mod this post only if you think others should/n't read this. I have enough ego^H^H^Hkarma. Thanks!
Hot chicks can make a difference. I think that Bob the Angry Flower said it best.
Wah!
See this treatment of Bell's Theorem for a well-written counter-argument. Note that the EPR paradox attempted to prove locality by invoking causality (no "spooky action-at-a-distance", according to Einstein), but ended up leading to Bell's work.
This post expresses my opinion, not that of my employer. And yes, IAAL.
Here's a thought for you: Time doesn't exist. It's an abstraction of change. For all practical purposes, it may as well exist because it helps us measure things. But aside from the fact that the relative positions of 3 dimensional objects change in those dimensions and that "time" is used to measure that rate of change, "time" per se as a physical phenomenon doesn't exist.
Now, position within the 3 dimensions and change of that position exists, but that's really it. Obviously change does exist, we see it happen all the time. Time is merely comparing one type of 3D change (e.g. a moving car) to another 3D change which is more constant (e.g. the ticks of an atomic clock).
Am I off my rocker here? Has anyone actually proved that time exists as a physical phenomenon? I can understand the usefulness of time within formulas, much as imaginary numbers are also useful. But like imaginary numbers, time has no natural physical presence.
Therefore, for us to speak of moving through the "dimension of time" in any "direction" doesn't make sense. There can be no time travel if time itself doesn't exist in the physical world, right?
Please mod this post only if you think others should/n't read this. I have enough ego^H^H^Hkarma. Thanks!
Yah, that puzzles me too. Why should time be a dimension at all?
Sure God could have made snapshot backups of all the possible universes but I still don't see why people talk about time as a dimension.
Do most physicists use time that way, or only to lay people?
Actually I heard the chef world is mainly male.
;).
But in many cases when the chef goes home, the wife cooks
Not sure why. But I believe I'm telling it like it is.
I heard people say that most women don't mind supporting roles. I suppose more (not all) guys do mind, and so they strive harder to be boss, chef, etc in their domains of interest.
Yes, time is different to the spatial dimensions; it's often converted into a distance-like quantity by multiplying by i and c (that's sqrt(-1) and speed of light). The other spatial dimensions aren't imaginary. The reason for the i is so that the metric for space-time in special relativity turns out to look like the Euclidean metric. In normal words, this means that you can write a "distance" in space-time (which is the same no matter how you "rotate" the axes, i.e. no matter what speed you travel at) as s^2=x^2 + y^2 + z^2 + (ict)^2. This is all special rel stuff, it gets much ickier when you look at general rel. The metrics (i.e. "distances") in space aren't Euclidean because of the curvature of space-time, and nothing seems to work out nicely.
One can think about "rotating" space-time because one uses the fictional time dimension as if it were a physical reality. And yet, time has never been physically shown to be a physical reality. What would Einstein's work have been like if time were not part of the equations?
Perhaps instead of thinking of objects that have a speed approaching the speed of light as having a slower time, we might think of them as having less total energy available for local phenomenon because so much energy is being used for overall movement? Just a thought. I'm not a physicist at all. I only know enough to get in way over my head. I just can't help but wonder how science and science fiction would have developed differently if time were not assumed to be physical.
Please mod this post only if you think others should/n't read this. I have enough ego^H^H^Hkarma. Thanks!
(1) Time is not just how fast things change. Time also provides a way of ordering observed events. I don't see how you could remove time from Einstein's equations. I mean, there are lots of situations where physicists make up "non-physical" quantities that aren't necessarily part of a physical understanding. These quantities could be more or less removed from the physical equations. Many people would consider electromagnetic fields to be non-physical, for example. I've actually never seen a clear definition of what a "physical quantity" is, but time and space are pretty much assumed to be physical. In classical quantum mechanics, time is treated as a parameter of the system, not as an observable (i.e. physical quantity in the normal sense) like position, energy, momentum etc. I think though, in relativistic quantum mechanics, time is an observable, because otherwise the relativistic transformations wouldn't work correctly. It's hard to get anywhere if you don't want to assume that there's anything like time that really exists.
(2) Objects travelling near the speed of light don't actually have slower time, they just seem to from a "stationary" observer. The reverse also applies: the stationary observer seems to have slower time from the point of view of the "moving" object. So neither observer's time is actually slower. When objects accelerate, e.g. in the twin paradox, then you can say that one object's time is going slower than anothers, but that's a whole new kettle of fish.
(3) If the total energy available were to change between different reference frames in the way that you describe, it probably would mean that different outcomes are observed in different reference frames. This is a bad thing, if say one observer sees something blow up and another observer sees it stay intact. As it is, the total energy of an object does depend on the observer (the kinetic energy changes in different reference frames), but this energy doesn't necessarily affect the internal workings of the moving object.
Anyway, if you want to read a good popular account about this sort of stuff that gets the details right, I'd recommend The Elegant Universe by Brian Greene. It doesn't cover the theory specifically mentioned in this article, but covers a "competing" theory, string theory. On the way, it also discusses special and general relativity, the nature of space and time, quantum mechanics, extra dimensions, and all sorts of other fun stuff.