Posted on 05/25/2004 8:01:29 PM PDT by Ronzo
Edited on 06/07/2005 12:27:06 PM PDT by Jim Robinson. [history]
Can you access the flash of emancipation you felt the first time you were able to stay up on a bike or propel yourself through the water? Can you remember the way your new knowledge enhanced your life? And can you recall the gratitude you felt toward those people who had the skill and the patience to pass that knowledge along to you?
(Excerpt) Read more at theatlantic.com ...
Actually, weare all figments of something's imagination!
I recently read Greene's THE ELEGANT UNIVERSE. I was very impressed with the clarity of his explanations for non-physicists like me. I bought his arguments about the "elegance" of including additional dimensions to reconcile quantum mechanics with special relativity in a grand unification of forces. I even understood that I was not supposed to be able to fathom the other dimensions, even after because in the model they would have to be too small in scope to probe.
Greene did a wonderful job explaining the "standard model" theories and their limitations. However, I was a bit disappointed about some of the later chapters on string theory. I felt queasy everytime he mentioned Calabi-Yau shapes or certain paradoxes like this, "According to the light string modes, the universe is large and expanding; according to the heavy modes it is tiny and contracting." (p. 251) At certain points the physics almost became a dissertation on topology and I lost grasp of why the details of a theory about strings too small perhaps to be detected would be relevant to any laymen except the very most interested. Black holes, and space-time relativity (an example he gives about extending the life of particles called muons by accelerating them was trippy), as counterexamples, seem inherently cool to many people. (There is also a fascinating example about walking through walls undisturbed, something that could, but VERY unlikely, happen b/c of uncertainty principles.)
Having stated what I thought were the books shortcomings, I have to say that I enjoyed it tremendously on the whole, appreciated Greene's effort to explain something very complex to non-physicists, and took on faith that the mathematics he alludes to do make string theories worthy endeavors for physicists to pursue.
When physicists can explain the universe as simply as understanding a computer, then I'll be ready for them!
Well, the simplicity was expounded upon over dozens of pages. It wasn't so simple that I didn't have to reread certain things or that I could regurgitate everything to another person. Let's just say I had a sense that I was absorbing most of the information, at least until he started getting into the details of string theory. Greene's explanations of concepts were colorful and presented in small enough pieces for me to comprehend. By the way, I am speaking of THE ELEGANT UNIVERSE and not the book emphasized in the interview link, though both are about the same topic.
Dammit, I spent 8 years learning to be an arrogant prick! Don't dismiss it so quickly. You laymen need to learn the fine points of arrogance...
"I didn't spend 5 years in evil medical school to be called Mister." - Dr. Evil
The flash of inspiration. These days it's not so much flash as ooze.
LOLOLOL! Thanks for the ping!
I do, Alamo-Girl; but Green seems to suggest that, however many dimensions there are -- 11 in current string theory -- that only one of them will be a time dimension. It seems the balloon analogy -- of the inflationary universe -- allows for those tiny, crabbed, "curled up" ten spatial dimensions to do all their work in one time dimension -- the one that we can "picture." At least, that appears to be the jist of Green's presentation. Once the universe has expanded sufficiently, the idea is the harmonic signatures of these teensy curled up dimensions become "audible," and therefore observable.
If such observations confirm the mathematical predictions, we're home free -- string theory can be said to have been observed in action.
And yet I have questions, probably idle ones. One is that for string theory to be correct, we must understand that it has been at work regardless of the space/time frame that enables us to recognize it. If the theory is correct, and these ten spatial dimensions altogether specify every particle known and yet unknown in the universe, then obviously, they have always been doing that, "from the beginning." If we add the idea of vacuum fields, or zero point fields, each with its own signature particle, then we are effectively dealing with a universal phenomenon, for fields are understood to be universal. My question is: Where do we put the idea of universality into a framework that calls for only one dimension of time? It seems to me that, in a very real sense, universality carries the idea of that which is timeless, ever persisting at least so long as the universe lasts.
He writes, "...conventional theories do break down when you try to push them all the way back to the beginning. We believe that string theory does not break down, but it still is a very complicated theory when you try to apply it to time zero itself. So far, no string theorist has succeeded in using the theory to peel back the obscuring layers and reveal what happened at the start. But the hope is that we will shortly be able to do that."
I dunno. It may be premature to start numbering time dimensions before we can understand what happened at "time zero." I wonder what the math might have to say about that.
Maybe someone can shed further light on these intriguing issues.
Please correct me if I am wrong but wasn't it Einstein that said time was a creation, a persistant illusion? If you will permit me to be a little metaphysical, I would like to think that the other strings we cannot see are dimensions of the spiritual - angels, demons, our spirit. Since God spoke the world into being (see Genesis 1) would it not also make sense that he controls events in all dimensions through sound? These filaments (strings) are sound in particle form, correct? Another analogy I like to think about is that we are dancing on the strings of God's violin. So to get back to my idea, if time is created but does not seem to apply to God or the spiritual world, then it would make sense to me that time is only one dimension - one that we can sense. What do you think?
"Whereof we cannot speak thereof we must remain silent."
Wittgestein's excellent, and timeless, advice.
Indeed, Greene is only speaking in the interview of the conventional, compactified Kaluza-Klein extra spatial dimensions, but in his presentation on PBS (I think it was) he also spoke of the higher dimensional theories, inter-dimensionality and included Cumrun Vafa in the program (extra time dimensions). For that reason, I believe he is open to the other theories as well.
Plus, he said this in the article:
But I digress...
I certainly do agree with you that it is premature to count the dimensions or to characterize them in terms of number of spatial and number of temporal or to require that they be in total compactified or higher dimensional!!!
Einstein said that "Reality is an illusion, albeit a very persistent one."
And you are right on target with the observation that space/time is created as the universe expands. It doesn't pre-exist. Space/time are not separate in the math, i.e. time is geometric.
And the point you raise about harmonics is at the root of the physical realm whether looking at string theory or quantum field theory. The strings are not however in particle form, they are the structure (the geometry) of the harmonics.
What we sense as time passing is often called an arrow of time or a timeline. In relativity it may be called a worldline. But time to us at these space/time coordinates of the universe are not the same as it would be to someone elsewhere.
For instance, on a black hole a week might elapse while on earth it would be 40 years. Here is a great website with graphics and animations to help explain special relativity: The Space/time Wheel. Be sure and check out the chart at the bottom and then start with the postulates at the top menu and browse through the graphics. It is a beautiful presentation!
When I first read the following article, the Scriptures about God speaking it all into being welled up inside of me!
The MAXIMA, BOOMERANG, and DASI collaborations, which measure minute variations in the CMB, recently reported new results at the American Physical Society meeting in Washington, D.C. All three agree remarkably about what the “harmonic proportions” of the cosmos imply: not only is the universe flat, but its structure is definitely due to inflation, not to topological defects in the early universe.
The results were presented as plots of slight temperature variations in the CMB that graph sound waves in the dense early universe. These high-resolution “power spectra” show not only a strong primary resonance but are consistent with two additional harmonics, or peaks.
The peaks indicate harmonics in the sound waves that filled the early, dense universe. Until some 300,000 years after the Big Bang, the universe was so hot that matter and radiation were entangled in a kind of soup in which sound waves (pressure waves) could vibrate. The CMB is a relic of the moment when the universe had cooled enough so that photons could "decouple" from electrons, protons, and neutrons; then atoms formed and light went on its way.
Are you an anti-metaphysical logical positivist or did I just annoy you?
No - not a Wiener Kreis acolyte. ;^)
Just common sense English analytical school.
Now that was a WIERD book (Slaughterhouse Five)....but must reading...
Personally, I think there's something to the idea of time being ultimately non-linear, though Greene obviously doesn't think so, nor do any of the string theorists. If time is one-deminsional, it can't be anything but linear.
Usually the Atlantic Monthly does not allow this sort of sillyness...must have gotten past the editors. But then they do like those big $5 words...even if they don't use them very well...
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