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Mind-bending article about the reality of existence.
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Read this in the paper today. It touches on many scientific issues mostly related to quantum and astrophysics..which I've always been interested in. A very intriguing read. Tell me what you think.
[EDIT]I've gone through and bolded the more thought-provoking parts.
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Reality check: Scientists share ideas on the mysteries of existence
04/01/2002
By TOM SIEGFRIED / The Dallas Morning News
PRINCETON, N.J. – "Great caution must be exercised," wrote the German physicist Max Planck, "in using the word real."
Therefore, physicists attending a recent meeting in Princeton should have been really careful. Instead, they threw Planck's warning to the wind. At a symposium convened to explore "Science and Ultimate Reality," speakers abandoned usual scientific caution to speculate on the mysteries of existence while celebrating the career of John Archibald Wheeler.
Wheeler, a professor emeritus from both Princeton University and the University of Texas at Austin, turned 90 last year.
He is known as a pioneer in explaining nuclear fission, as a champion of Einstein's theory of relativity (and coiner of the name "black hole"), and as an inspirational intellectual father for several generations of younger physicists.
In his later years, Wheeler has focused on quantum physics, groping for solutions to the mysterious description of nature that Planck introduced into physics over a century ago.
At the symposium, many of Wheeler's academic progeny – along with other scientists and scholars from around the world – explored quantum questions and other issues relevant to understanding reality. Some participants described new experiments offering clues to reality's mysteries. Others articulated wild ideas beyond the power of any present-day experiment to test.
Several hinted that whatever shape "ultimate reality" turns out to take, it need not resemble the commonsense reality that most people now perceive.
Some realms of reality may possess more dimensions of space than the ordinary three, for example. Different laws of nature may rule in different domains of space. For that matter, nobody knows how many domains there are – the universe accessible to human perception may be just one of countless bubbles of space that stretch not only beyond view, but beyond any imaginable view. Space itself, supposedly embodying the simplicity of nothingness, may turn out to be vastly more complicated than anyone can envision.
It's impossible to "see" space, of course. But ordinary experience suggests that space is limited to three dimensions (four if you count time, as Einstein's theory of relativity requires). After all, any physical object possesses only three dimensions – length, breadth and height. And any position in space – say, over the surface of the Earth – can be specified by three numbers: latitude, longitude and altitude.
But modern theories of space, time and gravity indicate that nature may be concealing additional dimensions, said physicist Lisa Randall of Harvard University.
"Extra dimensions might teach us new things," she remarked at the symposium. "I think we'll learn things about gravity that we really hadn't anticipated."
It may be, she noted, that the "true" number of dimensions differs from one place in the universe to another.
"You would conclude that the dimensionality of space is different depending on where in space you are," she said. "Experimentally, we don't know that the universe is four-dimensional, we just know that the part of the universe we see is four-dimensional."
In fact, Dr. Randall said, the four-dimensional "spacetime" that humans occupy may be just one of many such regions floating in a higher-dimensional space.
Four-dimensional realms residing in a bigger space sound like the parallel universes of science fiction. And it may be that "ultimate reality" embodies those and several other species of otherworldly realms, said physicist Max Tegmark of the University of Pennsylvania.
The latest evidence from astronomy suggests that the universe is literally infinite in extent, he pointed out. If so, all of reality must dwarf the comparatively tiny sphere of space (billions of trillions of miles across) that human telescopes can probe. In fact, Dr. Tegmark noted, reality could contain an infinite number of additional spheres equal in size to the universe we see.
In such an unlimited multiplicity of spaces, every possible arrangement of atoms must sooner or later occur in some realm somewhere, and in fact would occur over and over again in realms more and more distant.
Consequently, whoever you are, many other yous exist far away – very far away. Dr. Tegmark calculates that the nearest copy of any earthling would most likely be at a distance (in miles) computed by multiplying 10 times itself 100 trillion trillion times.
Still, all such distant realms of space would really be part of the one universe we live in – the other realms, though far off, would be connected, and the laws of physics would remain the same throughout all that infinite space.
But theorists have suggested the existence of yet another type of parallel universe. This view holds that the known universe was born 14 billion years ago when a tiny bubble of space in a primordial chaos suddenly inflated to a vastly larger size and then continued to expand. Other bubbles of space probably inflated as well, generating parallel bubble universes disconnected from the space that humans occupy.
Most such bubbles might not have any occupants at all. The laws of physics could be different in each bubble, and most conceivable sets of laws would not allow the complexity of life to evolve.
For example, Andrei Linde of Stanford University pointed out in another talk at the symposium, some bubbles might have collapsed before life had time to get started. And bubbles that grew bigger may have contained different sets of particles and forces, some incompatible with life.
Such inflationary bubble universes owe their existence to quantum physics, the source of many of reality's deepest mysteries. When Planck introduced quantum theory in 1900, he merely believed that it required energy to be packed in bundles, or quanta. By the 1920s, though, other physicists realized that the quantum nature of energy implied more radical consequences. Quantum rules require that nature behave in an inherently unpredictable way. Physicists may compute only the odds that any process will take place from among many possibilities permitted by quantum equations.
Quantum theory's multiple possibilities create yet another species of parallel universe, many physicists contend. In 1957, the physicist Hugh Everett III proposed that all the quantum possibilities are real, just in separate "branches" of the universe's history. "Ultimate" reality would therefore contain many universes, encompassing all the possibilities that quantum physics allows. In one such universe, for example, Kent State's basketball team won this year's Final Four.
Of course, people don't experience many realities, just one. But just because they go unnoticed doesn't mean other realities aren't there. Nobody notices the rotation of the Earth, either, physicist Bryce DeWitt of the University of Texas at Austin noted in his talk at the symposium.
One reason multiple realities might go unnoticed is that they don't stay around very long, said Wojciech Zurek of the Los Alamos National Laboratory in New Mexico.
Quantum physicists routinely cope with multiple realities in studying subatomic particles. An electron, for instance, can seem to travel through space by different paths, occupying no precise position until someone measures it, freezing one location out from the multiple possibilities.
In real life, though, larger objects always seem to possess a specific position. Chairs are never fuzzy clouds wandering around a room the way electrons buzz around atoms, for example.
Physicists have long pondered why big objects don't behave like electrons. Dr. Zurek and others have suggested that a big object's environment acts like a physicist measuring an electron. Light or atoms in the vicinity bounce off the object, recording a specific location from among all the quantum possibilities. In a tiny fraction of a second, so much interaction occurs that the object is localized, long before humans could notice any fuzziness in its location.
True, some atoms may have interacted with the object when it was in another possible place. But human observers perceive such a tiny fraction of all reality that the odds favor seeing only one of the many possibilities – the one recorded most robustly by environmental interactions.
"When we perceive a system, we intercept a tiny fraction of the environment that has interacted with that system," Dr. Zurek explained. "If this fraction is so tiny, this means the environment can reveal to us only the observables of the system which were recorded redundantly."
Other possibilities therefore lose their meaning, at least as far as people are concerned.
"We have no chance of seeing these other parallel universes," said Dr. Zurek. "We are stuck here and that's it."
Physicists still argue, though, about whether those other quantum possibilities should count as part of reality. Dr. Zurek doesn't think so.
"To me," Dr. Zurek said, "reality is the touchable everyday reality."
Dr. Tegmark, however, favors this "many worlds" view of quantum physics, and suggests going even further. Maybe yet another type of parallel universe exists, governed by entirely different webs of mathematical equations from those that human scientists know.
"My own personal guess ... is that you have a mathematical democracy, and any structure that exists mathematically exists physically, too," Dr. Tegmark said.
Dr. Linde expressed similar sentiments, suggesting that different mathematical universes would contain different kinds of particles, and different kinds of life.
But life's complexity would be possible, he said, only in realms where the mathematical structure provided an effective description of reality. In some realms the mathematical rules would not permit structures to form that retained any memory of past events. In a situation of such instability, math would be useless and life could not exist.
Therefore the effectiveness of math for science arises naturally in universes where life is possible, Dr. Linde suggested.
"We live in places where stability is possible, and by definition mathematics is efficient there," he said.
Of course, human scientists have yet to solve all the mathematical problems the universe poses. How to merge the math of quantum physics with Einstein's theory of gravity has perplexed physicists for decades.
A hint to the ultimate solution may come, though, from a view of reality modeled on holograms, two-dimensional images that give the appearance of 3-D reality. Perhaps the whole of 3-D space is generated by physical processes occurring on a two-dimensional surface, suggested Juan Maldacena of the Institute for Advanced Study in Princeton.
Clues from the study of black holes – regions of space surrounding intense gravitational fields – suggest that the space and time inside can be fully described by information stored on the black hole's surface. It sounds bizarre, like the entire text of a book being written on its cover, or the contents of a room being contained on its walls.
But you can imagine a room with walls covered by mirrors, two-dimensional surfaces recording three-dimensional images. And it may just be that the universe as a whole shares similarities with black holes.
If so, the space and time that humans live in may be reflections of distant processes. The Milky Way galaxy may be just one of billions contained in a superhuge sphere, with the laws of nature, including the existence of space and time itself, depending on what happens on that sphere's surface.
"Spacetime is like an emergent property," Dr. Maldacena said, which exists because of the interaction of particles on the universe's outer boundary. It's as though the very existence of the interior of the Earth depended on people interacting on the surface.
It's a strange idea, of course, but such complexity may turn out to be the only way to explain reality's apparent simplicity. Wheeler himself has suggested as much.
"We will first understand how simple the universe is," he has often said, "when we recognize how strange it is." |
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| AnotherWay83 |
great article...thanks for posting it..love this kind of stuff, read the whole thing :D
i do think there are other universes out there by the way, because i firmly believe that there is much, much more to reality than meets the eye...thats all i can say really...
peace |
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| Tranex02 |
| I love this kind of stuff....can't stop thinking about it....:D |
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| Fir3start3r |
| Go rent the movie "ONE" w/ Jet Li...it's easier to read...:p |
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| ali92 |
| Great article! I'm VERY interested in these kind of topics! |
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| davinox |
| thx 4 da article. i luv this stuff. |
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| Gekhous |
| what ever happened to summarizing stuff?? :) |
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| S-Type |
omg my head hurts from reading halfway thru...
spent all night studying for an exam that i just took.... brain is FRIED... can't comprehend any of this
will read it after i take a loooong nap, maybe it'll make sense then... maybe it won't
but as of right now... i'm pulling these outta the article :conf: :conf: :conf: :conf: :conf: :conf: |
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| SoulSupply |
| Did any of ye read michael crichtons book, Timeline? it deals with this kind of thing, great book... |
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| yujie__ |
| interesting, i wonder how long will we be able to find a way to travel to other dimension or survive a trip through a worm/black hole. |
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| DJ Mikey Mike |
| quote: | Originally posted by yujie__
interesting, i wonder how long will we be able to find a way to travel to other dimension or survive a trip through a worm/black hole. |
well i would imagine we would need to find ways to explore deep space first and the only way to do that is it develop ways to break the speed of light. There are theories on how to do this, but at present they are only theories, and will remain theories for years and years to come.
btw if anyone is interested in the article above, try reading books by stephen hawking. His stuff is amazing |
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| Endlesswave |
| quote: | Originally posted by DJ Mikey Mike
well i would imagine we would need to find ways to explore deep space first and the only way to do that is it develop ways to break the speed of light. There are theories on how to do this, but at present they are only theories, and will remain theories for years and years to come.
btw if anyone is interested in the article above, try reading books by stephen hawking. His stuff is amazing |
Ummmmmmm read a book called "Hyperspace" by Michio Kaku, explains all that type of stuff. Previously travel through an actual black hole was thought to be impossible but now...well here is a quotation or two:
A retouching of the black hole theory by Schwarzschild is shown in this quotation “Kerr found, however, that a massive rotating star does not collapse into a point. Instead, the spinning star flattens until it eventually is compressed into a ring, which has interesting properties. If a probe were shot into the black hole from the side, it would hit the ring and be totally demolished. The curvature of space-time is still infinite when approaching the ring from the side. There is still a “ring of death”, so to speak, surrounding the center. However, if a space probe were shot into the ring from the top or bottom, it would experience a large but finite curvature; that is, the gravitation force would be finite.” (Kaku, P. 227)
and also...
“This rather surprising conclusion from Kerr’s solution means that any space probe shot through a spinning black hole along its axis of rotation might, in principle, survive the enormous but finite gravitational fields at the center, and go right on through to the mirror universe without being destroyed by infinite curvature. The Einstein-Rosen bridge acts like a tunnel connecting two regions of space-time; it is a wormhole.” (Kaku, P. 226
Insane stuff...:D :eyes: |
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