Parallel Universes

Discussion in 'Physics & Math' started by Fathoms, Aug 29, 2001.

  1. Fathoms Banned Banned

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    *Is trying to improve typing skills*

    This is an article I'm transferring from September 2001 Discover Magazine. It's a really engaging read...


    If quantum theory weren't valid, no one would be walking around with cell phones or Palm Pilots. So physicist David Deutsch wonders this: Why do so many smart scientists ignore the larger implications of quantum mechanics?
    By Time Folger

    At Three o'clock on a warm summer afternoon, I arrive as scheduled at David Deutsh's home in Oxford, England. Deutsch, on e of the world's leading theoretical physicists, a distinguished fellow of the British Computer Society and champion of what must certainly be the strangest scientific worldview ever created, is something of a recluse. He likes to sleep late and warned me not to come too early. Although I'm on time, my knocks on his door go unanswered. The house is dark and quiet. The doorbell doesn't seem to be working. After about 10 minutes a light goes on in an upstairs window, followed by the sound of running water. I knock harder, which at last triggers activity on the other side of the door. I hear feet pounding down stairs; the door opens, and Deutsch asks me to come in.

    Piles of precariously stacked books line the route of his office, rising from the floor like stalagmites. A larger poster of a brooding Albert Einstein hangs on one wall. Deutsch sits, sipping orange juice. He is slender, with birdlike attentiveness, and for someone who hardly ever leaves his home, surprisingly friendly and open. He looks much younger than 48. If his arguments, which have won over more than a few of his colleagues, turn out to be correct, our meeting is also occurring countless times in innumerable parallel universes, all in perfect accord with the uncanny laws of quantum theory.

    Few physicists deny the validity of these laws, although they might not agree with Deutsch's interpretation of them. The laws insist that the fundamental constituents of reality, such as protons, electrons, and other subatomic particles, are not hard and indivisible. They behave like both waves and particles. They can appear out of nothing a pure void-and disappears again. Physicists have even managed to teleport atoms, to move them from one place to another without passing through any intervening space. On the quantum scale, objects seem blurred and indistinct, as if created by a besotted god. A single particle occupies not just one position but exists here, there, and many places in between. " That quantum theory is outlandish, everyone agrees," says Deutsch. It seems completely in conflict with the world of big physics according to Newton and Einstein.

    To grapple with the contradictions, most physicists have chosen an easy way out: They restrict the validity of quantum theory to the subatomic world. But Deutsch argues that the theory’s laws must hold at every level of reality. Because everything in the world, including ourselves, is made of these particles, and because quantum theory has proved infallible in every conceivable experiment, the same weird quantum rules must apply to us. We, too, must exist in many states at once, even if we don’t realize it. There must be many versions of late-rising David Deutsches, Earth, and the entire universe. All possible events, all conceivable variation s on our lives, must exist, says Deutsch. We live not in a single universe, he says, but in a vast and rich “multiverse.”

    He knows the idea takes some getting used to, especially when one pauses to consider what it means on an everyday level. For starters, it solves once and for all the ancient question of whether or not we have free will. “The bottom line is that the universe is open,” Deutsch says. “In the relevant sense of the word, we have free will.”

    We also have every possible option we’ve ever encountered acted out somewhere in some universe by at least one of our other selves. Unlike the traveler facing a fork in the road in Robert Frost’s poem “The Road Not Taken,” who is “sorry I could not travel both/ And be one traveler,” We take all the roads in our lives. This has some unsettling consequences and could explain why Deutsch is reluctant to venture from his house.

    Driving a car, for example, becomes extremely hazardous, because it’s almost certain that somewhere in some other universe the driver will accidentally hit and kill a child. So should we never drive? Deutsch thinks it’s impossible to control the fate of our other selves in the multiverse. But if we’re cautious, other copies of us may decide to be cautious. “There’s also the argument that because the child’s death will happen in some universes, you ought to take more care when doing even slightly risky things,” he says.

    Coming from a physicist of lesser stature, such startling views might be dismissed. But Deutsch possesses impeccable credentials. While still in his early thirties he created the theoretical framework for an entirely new discipline called quantum computation. Spurred by those ideas, researchers around the globe are attempting to construct a fundamentally different type of computer that is powerful almost beyond imagining.

    Deutsch himself is more interested in convincing physicists that quantum theory has to be taken into consideration in the everyday world than he is in seeing a quantum computer built. Physicists may argue about what the theory means, but fortunately for the rest of us they have no qualms about working with it. By some estimates, 30 percent of the United State’s gross national product is said to derive from technologies based on quantum theory. Without the insights provided by quantum mechanics, there would be no cell phones, no CD players, and no portable computers. Quantum mechanics is not a branch of physics; it is physics.

    And yet 101 years after it was first proposed by German scientist Max Planck, physicists who work with the theory every day don’t really know quite what to make of it. They fill blackboards with quantum calculations and acknowledge that it is probably the most powerful, accurate, and predictive scientific theory ever developed. But as Deutsch wrote in the article for the British journal for the Philosophy of Science: “Despite the unrivalled empirical success of quantum theory, the very suggestion that it may be literally true as a description of nature is still greeted with cynicism, incomprehension, and even anger.”

    To understand why the theory presents a conceptual challenge for physicists, consider the following experiment, based on an optical test first performed in 1801 by Thomas Young:

    In the experiment, particles of light-photons-stream through a single vertical slit cut into a screen and fall onto a piece of photographic film placed some distance behind the screen. The image that develops on the film isn’t surprising-simply a bright, uniform band. But if a second slit is cut into the screen, parallel to the first, the image on the film changes in an unexpected way: In place of the uniformly bright patch, the photons now form a pattern of alternating bright and dark parallel lines on the film. Dark lines appear in areas that were bright when just one slit was open. Somehow, cutting a second slit for the light to shine through prevents the photons from hitting areas on the screen they easily reached when only one slit was open.

    Physicists usually explain the pattern by saying that light has a dual nature; it behaves like a wave, although it consists of individual photons. When light waves emerge from the two slits, overlapping wave crests meet at the film to create the bright lines; crests and troughs cancel out to produce the dark lines.

    But there’s a problem with this explanation: The same pattern of light and dark lines gradually builds up even when photons pass one at a time through the slits, as if each photon had somehow spread out like a wave and gone thorough both slits simultaneously. That clearly isn’t the case, because the distance between the two slits can be hundreds, thousand, or in principle, any number of times greater than the size of a single photon. And if that isn’t confusing enough, consider this: If detectors are placed at each slit, they register a photon traveling through only one of the slits, never thorough the both t the same time.

    Yet the photons behave as if they had traveled through both slits at once. The same baffling result holds not just for photons but also for particles of matter, such as electrons. Each seems able to exist in many different places at once but only when no one is looking. As soon as a physicist tries to observe a particle-by placing a detector at each of the two slits, for example-the particle somehow settles down into a single position, as if it knew it was being detected.

    Most physicists, when pressed, will usually say that the lesson quantum mechanics has for us is that our concepts of how a particle should behave simply don’t match reality. But Deutsch believes that the implications of the theory are clear: If in every case a particle-be it a photon, an electron, or any other denizen of the quantum world-appears to occupy more than one position at a time, than it clearly does occupy many positions at once. And thus so do we, and so does everything else in the universe.

    But is that an awfully big conclusion to draw from a simple pattern of light and shadow? Deutsch responds by pointing out that a similarly huge assumption-that the universe is expanding-is base on subtle light and shadow observations. Yet hardly any physicist anywhere disputes it.

    Under normal circumstances we never encounter the multiple realities of quantum mechanics. We certainly aren’t aware of what our other selves are doing. Only in carefully controlled conditions, as in the two-slit experiment, do we get a hint of what Deutsch calls the multiverse. That experiment offers a rare example of two overlapping realities, in which photons in one universe interfere with those in another. In our universe, we see a photon passing through one slit that seems to interact with another, invisible photon traveling through the second slit. In another universe, the photon that we see is invisible to the physicist in that world while the one that we can’t see is the photon the otherworldly physicist detects. Peculiar? Deutsch believes there is no other alternative way of looking at quantum mechanics. “When it comes to a conflict about what a theory of physics says and what we are expecting, then physics has to win.”

    Deutsch is not the originator of the multiverse concept. That credit goes to Hugh Everett, whose 1957 Princeton doctoral thesis first presented what has come to be called the “many worlds” interpretation of quantum mechanics. In

    In creating the many worlds view, Everett was trying to solve the problem of why we see only one of the multiple states in which a particle can exist. Some years before Everett’s work, physicists had crafted an ad hoc explanation that to this day remains the standard way of cooping with quantum phenomena. In the conventional view the very act of our observation causes all the possible states of a particle to “collapse” abruptly into a single value, which specifies the position, say or energy of the particle. To understand how this works, imagine that the particle is an e-mail message. When the message is sent, there are multiple possible outcomes: The e-mail could reach its intended destination; any number of people could get it by mistake; or the sender might receive a notice that the message could not be delivered. But when one outcome is observed, all other possibilities with regard to the e-mail delivery collapse into one reality.

    To some physicists the notion of collapse is an unsightly addition to quantum mechanics. Tacked on to smooth over the uncomfortable fact that the theory mandates multiple states for every particle in existence. And the collapse model creates its own problems: Because it says our observations affect the outcome of experiments, it assigns a central role to consciousness. “It’s an unpleasant thing to bring people into the basic laws of physics,” says Steven Weinberg, a Nobel laureate at the University of Texas.

    Everett labored to move beyond those laws, arguing that nothing like a quantum collapse ever occurs and that human consciousness does not determine the outcome of experimental results. He said the collapse only seems to happen from our limited perspective. Everett believed that all quantum states are equally real and that if we see only one result of an experiment, other versions of us must see all the remaining possibilities.

    Bryce DeWitt, the physicist who coined the term “many worlds” to describe this perplexing idea, remembers his first reaction to Everett’s paper. “I was shocked but delighted,” he says. By contrast, other physicists greeted Everett’s theory with resounding indifference. “The article appeared, and that was the end of it,” says DeWitt. “Just total silence.”

    The cool reception apparently didn’t faze Everett. Although he left physics to work on classified projects for the United States government, he remained convinced until his death in 1982 that he was right about quantum mechanics. And if the many worlds theory is true, Deutsch, for one, believes that other copies of Everett might remain alive somewhere in the multiverse.

    In 1976, a few years before he vanished from this corner of the multiverse, Everett, at DeWitt’s invitation, visited the University of Texas, where Deutsch was then a graduate student. Like Dewitt before him, Deutsch became a convert. “I don’t think there are any interpretations of quantum theory other than many worlds,” he says. “The others deny reality.”

    Deutsch argues that physicists who use quantum mechanics in a utilitarian way-and that means most physicists working in the field today-suffer from a loss of nerve. They simply can’t accept the strangeness of quantum reality. This is probably the first time in history, he says, that physicists have refused to believe what their reigning theory says about the world. For Deutsch, this is like Galileo refusing to believe that Earth orbits the sun and using the heliocentric model of the solar system only as a convenient way to predict the positions of stars and planets in the sky. Like modern physicists, who speak of photons as being both wave and particle, here and there at once, Galileo could have argued that Earth is both moving and stationary at the same time and ridiculed impertinent graduate students fro what this could possibly mean.

    “This dilemma of whether you should accept that the world really is the way a theory says it is or whether you should just think of the theory as a manner of speaking, has occurred with every fundamentally new scientific theory right back to Copernicus,” says Deutsch.

    “I’m not quite sure why physicists should be more ready to believe in planets in distant galaxies than to believe in Everett’s other worlds,” says DeWitt. “Of course the number of parallel universes is really huge. I like to say that some physicists are comfortable with little huge numbers but not with big huge numbers.”

    Indeed, most other physicists view the many worlds route as a road best not taken. Steven Weinberg, paraphrasing Winston Churchill’s quip about democracy, says: “It’s a miserable idea except for all the other ideas.” So which road does Weinberg choose? “I don’t know,” he says. “I think I come out with the pragmatic people who say, ‘Oh, the hell with it. I’m too busy.”

    Christopher Fuchs, a research physicist at Lucent Technologies’ Bell Labs, believes that quantum mechanics doesn’t tell us so much about the world itself as it does bout our interaction with the world. “It represents our interface with reality,” he says. “ I don’t think it goes further than that.” Fuchs believes that odd properties of quantum mechanics, such as the apparent ability of particles to exist in many places at once, merely reflects our ignorance of the world and are not true features of reality. “When a quantum state collapses, it’s not because anything is happening physically, it’s simply because this little piece of the world called a person has come across some knowledge and he updates his knowledge,” he says. “So the quantum state that’s being changed is just the person’s knowledge of the world, it’s not in the world in and of itself.”

    In Fuchs’s view, quantum mechanics describes a reality that shrinks away from us when we probe it too closely. “There’s a certain ticklishness to the world,” he says. “It is this extreme sensitivity of quantum systems that keeps us from ever knowing more about them than can be captured with the formal structure of quantum mechanics.”

    To Deutsch, such arguments are just complex rationalizations for avoiding the most straightforward implications of quantum theory. “It’s a tenable point of view to say I don’t know what the world is like,” he says. “The obvious question then is what is in fact happening in reality? If quantum theory is true, it puts heavy constraints on what the world can be like.”

    The most serious consequence of refusing to consider the many worlds view is that physicists will never advance to a new, deeper understanding of nature. Deutsch adds: “What one can hope for in the long run is that a new theory will be facilitated by understanding this present theory. Once you understand the existing theory, you have a handle on what you can change in it. Whereas if you don’t understand it, if it’s just a set of equations, then it’s astronomically unlikely that you will happen upon a better theory.”

    In the meantime, Deutsch is optimistic that the refined application of quantum mechanics principles will produce a tool that could bolster his argument for the existence of parallel universe. Many physicists around the world, including a team at Oxford with whom Deutsch works, are trying to build a quantum computer that would manipulate atoms or photons and exploit the particles’ abilities to exist simultaneously in more than one state. Those quantum properties would tremendously increase the speed and capacity of the computer, allowing it to complete tasks beyond the reach of existing machines. In fact, says Deutsch, a quantum computer could in theory perform a calculation requiring more steps than there are atoms in the entire universe.

    To do that, the computer would have to be manipulating and storing all that information somewhere. Computation is, after all, a physical process; it uses real resources, matter and energy. But if those resources exceed the amount available in our universe, then the computer would have to be drawing on the resources of other universes. So Deutsch feels that if such a computer is built, the case for many worlds will be compelling.

    It’s almost seven o’clock in the evening. Deutsch has been answering questions for nearly four hours and has not yet had breakfast. He invites me to his conservatory, and we clamber over book stalagmites to a glassed-in porch facing his backyard for steak and orange juice. Deutsch muses about why people have trouble accepting strange new ideas. “I must say I don’t understand the whole psychology of why people like some scientific theories and not others,” he says.

    He pauses briefly while he lights the “barbecue in a box” on which he will grill his breakfast. While the meat sizzles, he answers one last question: What if quantum theory is wrong?

    ””I’m sure that quantum theory will be proved false on day, because it seems inconceivable that we’ve stumbled across the final theory of physics. But I would bet my bottom dollar that the new theory will either retain the parallel universe feature of quantum physics, or it will contain something even more weird.”+++
     
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  3. Crisp Gone 4ever Registered Senior Member

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    Wrong view presented in article

    Hi Fathoms,

    Okay, the title of the article alone raises some doubt with me about the author's knowledge of what really is going on. The article seems to reflect that the entire scientific community is just a bunch of stubborn people who refuse to accept any new idea's.

    Wrong.

    The idea of parallel universa was (as the article mentioned) born in the 1950's. What the article doesn't addresses is how this idea stands to the other ("more common") idea's in quantum mechanics. And the short answer is that it is a matter of personal taste.

    Quantummechanics is only a mathematical tool for physicists. You put some numbers in the equations, and an answer pops out. The interesting part is ofcourse how the answer (which is a function called the "wavefunction") has to be interpretted. And this is where the road splits amongst scientists.

    The more convential idea is that the wavefunction has a statistical interpretation ( = the Copenhagen interpretation or also called the statistical interpretation of Born). This interpretation basically says that the wavefunction is related to the probability of finding a particle at a given location. This works out fine, the only "problem" is that it leads to some unconvential ideas on measurements (the collapse of the wavefunction being one of them, but this isn't that much of a problem, the article seems to handle it as the ultimate difficulty).

    Then there's the alternate universa/multiverse/parallel worlds/... interpretation this article is about. This interpretation is incompatible with the statistical interpretation of Born, and therefor is simply another view on quantummechanics. As the article mentions, the wavefunction is then interpretted to give the probability to find a particle in a given universe (out of the many parallel ones).

    Which interpretation you prefer, is entirely up to your personal taste. The experimental results are the same in both interpretations, so the interpretation question is a theoretical one. The only problem is that there is no direct way of determining experimentally which of the two interpretations is the right one, so this kinda moves the entire discussion in the domain of (science-) philosophy: is our universe the only universe ? what really happens when you perform a measurement ? ... Even though these are interesting questions, we'd better discuss them in a seperate thread

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    .

    The point I am trying to make is the following: Deutsch's interpretation is one of the many possible interpretations. Some people like the idea, some don't. At the moment it's not really a discussion of right or wrong, but rather one of personal taste. The article seems to bring the Deutsch interpretation as one of the most underrated idea's in the history of physics, being constantly ignored by the scientific community. Well, tastes just differ.

    Bye!

    Crisp
     
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  5. Xerxes asdfghjkl Valued Senior Member

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    Here's my opinion.

    This is the only universe. It is 0 dimensional due to the fact that it is NOTHING, space is NOTHING.

    I think you might be able to explain parrallel or other universes in an idea of past present and future.

    EG one second ago this universe was much different than it used to be, maybe a star or two exploded.

    -------------- Take these lines for example. Say they are
    -------------- the univese. the bottom is the past the
    -------------- middle is the present, and the top is the
    -------------- future. Its all the same universe, Same
    -------------- matter, same everything, you know what is
    going to happen because of what has already happened. The lines will change frames of state, and they probably wont change patterns because it hasnt in the past and theres no reason for it to change in the future. But no matter what happens you can determine that it is the same universe and always will be. This makes time an illusion, technically, because if you know the input (previous lines) then you would undoubtably know the output. This is just a simple example of the universe on a smaller scale. Now take into acount our universe.

    It has different energys, states of matter and each has their own charectarisitics. You know how it behaves basically and you know the input. But it is very difficult and probably inpossible to find and output because its on such a huge scale. I'd compare it to doing calculus before you can talk. technically its possible but in real life its just a waste of time.

    So my presonal belief is that so called diferent universes only exist as different frames. Its all the same universe and outcomes have already been determined by the input.

    Its all a matter of waiting.
     
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  7. Hypnogog Registered Member

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    Quantum Shmantum

    Hey Fathoms, I just read that article last night and had a thought which fits into the Magazine you brought up but not the actual article. Like so many things it's all a matter of context. The side bar on the page before said article has that buildup to the core reading and skimmed over "an ocean of particles continuously pops into and out of existence all around us...appear out of nowhere, only to vanish in an instant and be replaced by others." and I thought maybe these particles stream perpendicular to the multi-verse linking every one with it's 'closest relative' at every concievable point.
    There's more universal ponderence in my head but the rest is turltes all the way down.

    Also, I can see the whole 'What do you mean the Earth's not Flat

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    ?' thing. Not only is Multiverse easily dismissed as fictitious (because it does sound fanciful) but it is also potentially dangerous. But does it sound TOO crazy, crazier than say a table made up of billions and billions of little tiny things which are made up of even tinier things all of which has a quantity of empty space, or the Uncertainty principle. One should never suppose they know it all because that's usually when things change.
     
  8. Crisp Gone 4ever Registered Senior Member

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    Hi all,

    Elbaz,

    This assumes a completely deterministic universe, which I believe we do not live in. There's been a long thread on this at sciforums a while back, you can look it up if you like (the thread was started by Plato and I believe it was entitled "Incomplete determinism" - I also made some comments back then, but that was at a time that I was even more unexperienced than today and in the meanwhile I have rethought my vision).

    But to get back to the point: I do not think we live in a deterministic world, basically because of quantummechanics which is fundamentally indeterministic. The Heisenberg uncertainty relationship is one example of this.

    Hypnogog,

    The idea of a multiverse does sound crazier than a a table made of zillions of atoms and the uncertainty principle. The later two can be either deduced from logically arguments or can be directly observed. The idea of a multiverse cannot be deduced but is a postulation which leads to some interesting theories, but cannot directly be verified in ... I think the next couple of decades (to prove the existence of a multiverse we'd have to somehow escape from our universe to directly observe it... We can hardly leave our own planet yet

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    ).

    I am not entirely dismissing the multiverse idea. It's nice to have a theory about it handy somewhere in case we ever need it. But with these kind of idea's I always like to see some connection to reality before totally accepting it. Unfortunately the idea of a multiverse is growing more populary everyday, and I somewhat fear that the concept will soon receive the status blackholes have: everybody believes in them, and yet we still haven't observed one yet (ok, we have some clues and hints and phenomena that can be easily explained by black holes... but yet this does not directly prove their existence).

    Bye!

    Crisp
     
  9. Xerxes asdfghjkl Valued Senior Member

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    Crisp,

    At first chaos theory does sound catchy to most people who read about it, and I'll admit that it did have my belief - for a few seconds. If you factor in everything and by that I mean everything that in someway can play a role then you should be able to determine outcomes.

    EG you can calculate how a pool ball moves on a table but eventually you will be way off after enough bounces on the sides.

    Well if you factor in everything than you wouldnt be way off right??

    Anyway I dont want ot get into this whole subject because I know I'm right. But I will tell you that time is an illusion - technically. the future can be predicted based on the past right. Thats what the mayans did. They said something like time mirrors in cycles. They predicted the demise of their culture and the end of the world - 2011 2012 or something. They had many awesome predictions, Dont forget their preditctions were based on REALLY advanced math calculations. I believe in the whole pattern thing, could be anything like mirroring cycles. They probably had some advanced math equation or something like that saying how things tick. unfortunately most of their stuff is wiped out and archeologists just dont know.

    I wont force or try to make you believe. But I think its something you should look into.

    PS The uncertainty principle isnt law. That's in my book at least.
     
  10. Xerxes asdfghjkl Valued Senior Member

    Messages:
    3,830
    PS I dont think black holes lead to different universes. I think they lead to different TIMES in THIS universe.
     
  11. Crisp Gone 4ever Registered Senior Member

    Messages:
    1,339
    We're not even talking chaos theory here

    Hi Elbaz,

    Well, chaos theory was not even what I had in mind. If you take something "simple" as quantummechanics for example (by simple I mean something that has proven itself by means of experimentation and is not relatively new such as chaos theory).

    Quantummechanics is fundamentally indeterministic: when the math has finished its work in that theory, you're left with an outcome that tells you that the particle you are studying can show up at a thousand different places, each with their own probability. You can still be 99,9% sure that a particle will be where you expect it to be, but there's always that 0,01% chance that it shows up somewhere else (according to that theory).

    Now I believe that quantummechanics has some/alot of truth in it. It just works too well not to be true

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    . Especially the way it is consistent with (the deterministic) Newtonian mechanics, really reassures my faith in the theory.

    But in the end it comes down to belief, so I'll gladly accept if you believe nature to be fundamentally deterministic. I also thought that a while back, but after discovering the advantages of an "incomplete deterministic" (term (c) Plato) universe, I just had to let the idea go

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    .

    Bye!

    Crisp
     
  12. Radical Registered Senior Member

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    151
    taken from science.box.sk

    Total satellite secrecy approaches

    17:22 29 August 01
    Will Knight

    A portable system that will allow electronic messages to be transmitted to and from satellites in absolute secrecy has now been built by researchers at Los Alamos National Laboratory in New Mexico.

    The researchers will test the system to send quantum information 10 kilometres through horizontal free space at the start of September. Air density at this at this level approaches that experienced when transmitting information to a satellite 300 kilometres above the Earth.

    "This is a significant step towards that threshold," says Tim Spiller, of the Quantum Information Processing Group at Hewlett-Packard Laboratories in the UK. "This group is leading the world in this area."

    The furthest that anyone has yet managed to send this type of signal is just two kilometres. But Glen Peterson, who constructed the device at Los Alamos National Laboratory, is confident that the technology will work over 10 kilometres. He says that new photon projection and detection hardware promise to improve the system's accuracy dramatically.

    "The next step is to track a satellite and make sure we get the signals right," he says. "We have people developing the hardware to go into satellites."


    Sensitive state


    The new system consists of two devices that transmit and receive data encoded as individual photons with a quantum state. The laws of quantum physics mean that any interference with the data stream would disrupt the stream, leading to detection.

    Other research institutes have demonstrated quantum cryptography in the laboratory but the technique is not yet used to secure sensitive messages.

    In practice, quantum cryptography might only be used to update the "keys" used to lock and unlock encrypted messages sent through normal satellite links. This would greatly improve the security of satellite communications but not guarantee total secrecy.


    One time keys


    However, the system could be used to generate "one time" keys that would provide absolute secrecy for individual satellite communications, although these would require significantly more bandwidth.

    Experts say that the technique will probably not be used to perform the majority of communications, such as relaying internet messages, because significant extra cost and effort is required.

    "It's going to be used mainly in niche markets such as point-to-point government communications, where you need very high security." says Nigel Smart, a cryptography expert at the University of Bristol in the UK.


    17:22 29 August 01
     
  13. Merlijn curious cat Registered Senior Member

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    1,014
    Radical, please stop posting irrelevant messages.

    To my taste the multiverse theory ois just "too weird". By far I am not an expert, so I would like to have some help here.

    Is it possible that particles stretch into a temporal dimension as well?
    Effects like interference patterns can be accounted for in that way. In which case there is no interference with particles from parralel universes, but with the 'future state' of other particles coming (one at a time) through the holes. I think it would also readily explain the ERP experiment.
    The idea would seem to conflict with that of indeterminism, but that need not be. The case would just be that inderterminism would be apparent indeterminism, maybe like the "incomplete determinism"of 'Plato'. On the other hand, there is a flaw here... if there is a possibility of 'retrospective interaction' (or whatever you would like to call an interaction of the future state of a system with the current one) there must be a way to determine the future state of a system. Hmm. rethink rethink.
    as I said before. some help please. (maybe I just shouldn't try to make sense of things I have too little knowledge of).

    bye for now,
    Merlijn
     
  14. Bebelina Feminazi Messiah Valued Senior Member

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    4,997
    Universes

    I believe that there exists as many universes, parallell and other types, as we can ever imagine. There is no need to prove anyhting physically, that is not physical to begin with.
     
  15. Stryder Keeper of "good" ideas. Valued Senior Member

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    13,101
    Parallels and a Blackhole theory

    From what I understand our universe exists as an omniverse, which means there are many states of time and reality can converge with it's mutated clones on occasion.

    Take for instance my thought on the creation of the universe, it will tie in with other theories I am sure.

    A black hole we are lead to beleive is a star collapsed on itself causing some form of wormhole, this wormhole has such a gravity that almost all light and energy can't escape it's pull.

    My theory came to me when I realised that a collapsed Star (for those of you that don't know a star is like the sun) that forms a blackhole at the end of it's life, could have possible catalysed it's beginning.

    It means all mass that enters this blackhole or wormhole in the future, gets drawn at such a gravity and speed that it gets sucked back as energy into a previous point of that star/blackhole.

    Imagine a meteor hurtles into the centre and is accelerated to the point where it becomes pure energy, it's energy tranverses through the lifetime of the blackhole possibly still gathering speed.
    The energy is itself transported through time, back to it's beginning to possibly ending up re-entering normal space at some point.

    The point here is if that meteor's energy re-established it's structure on normal space re-entery, it would infact hit itself during the process of slowing down, causing a fission reaction.

    Of course in reality it would just be atoms and molecules that collide back at that point, and drawn to a location because of this wormhole's gravity, creating a star.

    This ties with the Steady Sate Theory, where the universe feeds itself material, So the future has much more mass than the start, but over time the amount of mass within the universe increases through this phenomona.

    Of course this also ties in with Hawking's explaination that there never was a singularity, I find this true because as soon as that first atom re-enters normal space it collides with itself (Probably changing from Hydrogen to Helium) and that would be the first step in a parallel creation as next the Helium might have another atom collide/re-enter at the same space.

    This would explain that with every atomic reaction in this theory, there would be a parallel, where that interaction might of been defined differently by Heisenberg's Uncertainty principle.

    I know of course in the Scientific world it is theoretically possible to create parallels, but I know to do so you would have to understand a certain rule (Which I shall try and explain in a method that people can understand)

    ---

    You walk to a T junction in a road, and feel queezy, your stomach rumbles slightly, you feel un-nerved, you might even say that someone has stepped over your grave.
    You eventually must your disorientated state to speak to the Man sat at the corner of the T-Junction with his Difference Engine.

    His difference engine is a clever piece of machinery, it can send information back through time, of course it has to be received by itself, so the only way it can send any information is through parallel processing. You don't know your path so you ask the difference machine man to help.

    He says to you "I don't know what's down each route, but what you could do is walk down either one of those roads, and then send a message back to yourself through my contraption... This should save you time because you could tell yourself about one path and walk the other"

    You agree it sound a good idea, you feel iffy again, as you have choice to make, you can either choose one of those paths to walk right now, or you can wait a minute for a "parallel" future self to tell you whats down one of the routes.

    At first you sit there and nothing happens.... "Silly me, I forget to say that if you do it I will send a message down to tell us you've taken a path" The difference man says, and with that a bell sounds.

    "It looks to me that you've taken the right path" He says in response to the bell.

    You wait for your parallel self to walk to route and find what is down that path, and a message tells you that it's a dead end.

    So you get on your feet and walk the left path in the same time span as you would have walked the right path.

    ---

    You might of noticed that I mentioned the effects of the Subatomic levels changing directions, this is entirely to do with the consequenses of the number of differences within the universe.

    Take for instance, If I was the difference man and I saved a train load of people, then those people that could have died are going to cause bizarre side effects to the universe as you know it, for instance they would interact with people that they wouldn't have interacted with if they had died. Possibly have families and kin that wouldn't have existed.

    Each being a variable causing some dramatic change on the people saved and their saviour.

    I hope that should explain what I know of parallels, Feel free to question anything mentioned.

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    Stryderunknown
     

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