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SuperString Theory Question

  1. Feb 25, 2004 #1
    I was wondering how a string could be a one dimensional vibrationg loop? I am still trying to remove myself from the 3 dimensional ideal of our world, however how can anything have only one dimension, for then it would imply that it has neither of the other two dimensions and therefore wouldn't exist.

    That would be if it was "matter" as we usually think of it. But both point particles and strings are "before matter", so they aren't bound by our everyday constraints. The string is truly one dimensional, and by existing in the time plus space dimensions of its background, it sweeps out a two dimensional surface, its "world sheet".

    But you have to know that modern string physics has things called branes which are multi-dimensional, and in some theories they are what constitute our spacetime.

    It almost seems with superstring theory that they add dimensions like epicicles were added when the first few ideas of our galaxy were being drawn up.

    The extra dimensions come straight out of the quantization of the strings. You can only do an anomaly free quantization in certain dimensions: 26 for bosonic strings, 10 for superstrings, and 11 for M-theory.

    Well just a question[?]

    Welcome to MKaku forum and Physics Forum. I hope we can help you with your lecture here.
    Last edited by a moderator: Feb 26, 2004
  2. jcsd
  3. Feb 26, 2004 #2


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    In usual atomistic theory, where particles are zero-dimensional, the background vacuum solves the problem, it "carries" distances and dimension.

    As in string theory a unit of geometry is already incorporated in the particle, they want to dispose of the vacuum, it is true. But currently there are not a background-independent string theory, so I am afraid your question is unaswered.
  4. Mar 26, 2004 #3

    Can I have one second of your time?

    Do you believe in Tachyons?

    Tachyons are a one dimensional 'time'-particle, which if they exist, must therefore exist in our own 3-D universe?

    With regards to your other comments I could agree more, right idea just the wrong direction, in my option. Harmonics not strings - music not sheet music - same sound - different interpretation.
  5. Mar 26, 2004 #4
    If everyone including Einstein for the past century has been hunt for the missing GUT, why did the M-Theory cause a major storm when it was simply provening that all the then current string-theories, were different mathematical paths leading to the same unique destination - The connection was always there, but it was Witten how proved it mathematically, were it was as Einstein who made his own connection in SP and GR......
  6. Mar 26, 2004 #5
    There are leading perspectives here that need to be considered. Braneworld has developed.

    http://www.tech.port.ac.uk/staffweb/seahras/images/Kaluza.jpeg [Broken]

    In 1919, Kaluza sent Albert Einstein a preprint --- later published in 1921 --- that considered the extension of general relativity to five dimensions. He assumed that the 5-dimensional field equations were simply the higher-dimensional version of the vacuum Einstein equation, and that all the metric components were independent of the fifth coordinate. The later assumption came to be known as the cylinder condition. This resulted in something remarkable: the fifteen higher-dimension field equations naturally broke into a set of ten formulae governing a tensor field representing gravity, four describing a vector field representing electromagnetism, and one wave equation for a scalar field. Furthermore, if the scalar field was constant, the vector field equations were just Maxwell's equations in vacuo, and the tensor field equations were the 4-dimensional Einstein field equations sourced by an EM field. In one fell swoop, Kaluza had written down a single covariant field theory in five dimensions that yielded the four dimensional theories of general relativity and electromagnetism. Naturally, Einstein was very interested in this preprint.

    http://www.tech.port.ac.uk/staffweb/seahras/neat_physics/extra_dimensions/gravity_and_EM.htm [Broken]
    Last edited by a moderator: May 1, 2017
  7. Mar 26, 2004 #6
    This is exactly the type of information I am looking for. As science progresses at an alarming rate, it is become far more difficult to findout the simplest of answers, that I feel we have lost sight of the big simply picture.
  8. Mar 31, 2004 #7
    string theroy works, imagine that the entire universe in made up of one thread created by the path of a photon and that the tread is connected to itself at beginning and end.
    how complicated would the "vibrations" in the thread have to be? well, as humans we can turn a closed shape into all sorts of things, like computers, mazes, words so on.

    every time you turn on your lights, concider the complexity of the rather complicated "sting" like circut that made it possible. now, multiple that complexity to some astronomical value and you have our "string" universe.
  9. Apr 3, 2004 #8
    Any theory that presupposes, there is more than one of a particular "thing," that is found to be the building block of the universe... will prove to be incomplete.
  10. Apr 3, 2004 #9
    1,2,3 .......n, n+1,.....,to infinity.

    If I told you what infinity was, would you believe it start as a single digit?

    Give me;

    1 photon, 1 electron, 6 quarks, in a Super Cloud

    And I'll give you the universe or infinity, which ever you prefer.....

    If you look for more complicated, I am sure you can find many examples, as with the 5 Superstring theories, but if you look carefully you will see they all derived from the same simple basic theory just looked at in a slightly different way.
  11. Apr 4, 2004 #10
    here is the kicker
    0 <-----what is that? it is the beginning and the end, it is nothing and everything.
    +1 + -1 = ? ....... -3 -2 -1 0 1 2 3 what does "0" represent here?
    lets write is better ... -3 -2 -+1 2 3 hmm. if 1 cannot be either negative or posivive it must be both. so what is 0 it is a circle that represents a thing with no beginning and no end, it simply IS.

    take a string and tie it at the ends to make a circle, then (without untieing it) knot it up into a tight ball.
    1. is it something more than a circle now (mathmatically)
    2. and is it still the same circle makeing it 2 things?

    multiply that to infinity and we have the convergence of string theory.
  12. Apr 4, 2004 #11
    Elementary Particles



    Figure 15-01 shows the size of the systems, which are governed by the rules in quantum theory. It starts from molecule with a size of 10-7cm to the hypothetical entity of string and membrane, which has a size of only 10-33cm. Figure 15-02 shows a proton composed of two up quarks and one down quark. According to the superstrings theory, these quarks are loops of string or string attached to a membrane at the scale of less than

  13. Apr 4, 2004 #12
    my problem with super-string is the multiplieng og these strings unneccisarily.
    the theroy works with just one string, if we multiply the "vibrations" to infinity.
    if we make the string sigular, its aspect becomes readily visable and the 4th dimension is defined. even more, we can deduce the nature of this string and predict cosmic events, such as quarks, gravity, electromagnitism, "weak-energy" so on. we can conclude that all of these "forces" are varients of the same energy. Light being the smallest "vibration" or "harmonic" within the string, weak force beong the "recoil" of the string, magnetics being the conectivity of the string to itself, and gravity being the connection of one harmonic to another. the string consisting of 1 photon either traveling "super-luminally" or inexplicable traveling at 0.
  14. Apr 4, 2004 #13
    Is there a Universal Scissor used by God?

    Thanks for images and link Sol.

    But still I see no answer how 'separate' strings are created.
    How? What mechanism? How the vibration starts in a single separated string? Where is a dynamic concept behind? Why is a gravity string separated from the other strings. Is it logic that gravity in separated from energy and matter? Why separation ... is there then a Universal Scissor used by a God?
    No answers.
    It stays a the level of out-of-blue magic.

    Where is the Occam's razor approach? Non.

    I have an alternative image what strings are. IMO
    strings are a mathematical expression of the local dynamics of the spacetime membrane. A string is the intersection of local spacetime geometry.
    Here it is: http://www.mu6.com/interconnectivity/spacetime_string.jpg

    If apply one - very, very, very, very, very - simple postulate: 'Space-time is a non-breakable membrane' we see and understand how Quantum packages might be created by a simple coupling. Quantum baskets will hold several layers (and it's that what we see in all fundamental particles and other events in Physics?).
    The structure of Quanta: http://www.mu6.com/interconnectivity/spacetime_holon.jpg
    A quantum package is thus a type of knot.
    As you see we don't need a Universal Scissor to come to knots. Do we need to cut a lace to close the shoe? cfr. lacing a shoe (http://www.fieggen.com/shoelace/) :rolleyes:
    So just the coupling of several spots of a very elastic spacetime membrane gives a multi-layered quantum knot.
    And knots can couple again with other knots. So your second image http://www.universe-review.ca/I15-01-quantumdomain.jpg will stay valid for the higher steps of matter. The consequence is that we have a non-commutative universe.

    When we don't have a Universal Scissor ... we keep interconnectivity which is essential for a TOE.

    So why stay on very complicated theories with uncertainty and without a logic concept behind?
    Why refuse to look into a non-breakable membrane concept that gives a simple and logic solution ... that is even confirming the combinations found in the Catalan numbers?
    Is the physics community masochistic? Or is it something else?

    These images are from my 'critics on ST' page: http://www.mu6.com/stringtheory.html

    Links to Catalan numbers:

    The Catalan numbers (1,1,2,5,14,42,132,429,1430,4862,16796,58786,208012,742900, 2674440,9694845,35357670, 129644790,477638700,1767263190,
    6564120420,24466267020, 91482563640,343059613650,
    1289904147324), named after Eugène Charles Catalan (1814--1894), arise in a number of problems in combinatorics.

    Name: Catalan numbers: C(n) = binomial(2n,n)/(n+1) = (2n)!/(n!(n+1)!).

    With pelastration I bring the catalan numbers also into a cosmologic concept.
    Last edited: Apr 4, 2004
  15. Apr 4, 2004 #14
  16. Apr 6, 2004 #15
    None vibrating superstring ?

    Let us assume that the whole universe was made for superstrings.

    Now lets assume that are sitting at the back of the theatre, we can hear the music but we are so far away we cannot see the musicians.

    We are so far away the musicians have stopped playing and have left the room, by the time the music has eventually reach us.

    Perhaps we are just listening and witnessing, the music pass us by, after the big bang party is already over.

    Just like the thunder and lighting, in a cloud in a thunderstorm.

    Or electrons and photons in a 11 Dimensional Super Cloud, (3-D, time and 6 Quarks)?

    What use is a superstring, which is not vibrating?

    Therefore all vibrating strings are simply harmonic vibrations and can no longer be considered as strings but as single dimensions or a harmonic wave.

    “The path on an electron or quark, is only create at the moment it is observed or heard?”
  17. Apr 7, 2004 #16
    By your very own work you recognize paradigmal changes can exist.

    You also understand the basis of superstring having incoporated the reality of GR and QM, and these things are not invalidated, but morphed into the reality of strings:)

    So having consumed, you now are both these things, and you understand the nature of the reality is very dynamical. You see this elastic nature of reality and the movements implied. Do you see it tearing? Non:)

    Assume for a minute the harmonal nature of reality,and where such congregations could meet. Intense vibration, and in spots, where this would not be so intense. If sound was to meter the discrete nature of this reality, what values would you assign both these positions?

    So do we then asssume a value to the density of vibration as a energy perspective? Or shall we assume that the density of discrete nature?

    The understanding here, is we have assigned a universal value (strings), that permeates below current reductionistic measures, and we use this overall measure, as a recognition of what any particle can be.

    Becuase you have labelled it pelastrian, the known dynamical nature has not changed. What is also measured is the harmonical nature.

    Its just two ways of looking at the same thing in terms of momentum and position ? Yet we understand very well the position can be determined, by the "peaks," in the hills and by nature, recognize the valleys.

    I am open to corrections.
    Last edited: Apr 7, 2004
  18. Apr 7, 2004 #17
    take a string tied together at the ends, arrange it in a perfect circle, then remove gravity and air. eventually the string will start to move in on itself, creating new shapes and "wave patterns" no lets assign some points on the string to base our measurements (as many or as few as you like on the circumfrance) now lets say these points (well work singular to make it easy) lets say a point on the string where it starts as a perf3ect circle is valued as 1, and as that point moves towards the center of our original cirle if goes up in value, lets work with pi and give the scale a 1 - 179 possible value (180 degrees -1 ) as our point moves towar the center adjacent points also change in value. now we have a picture of the sting doing its thing. remember that this is a globular experiment so it is neccisary to assign up and down, well say anything above the "equator" is positive and anything below negative. lets go a step farther and say literal position is neglegent and say any part of the string moving generally north is posative and any part moving generally south is negative. now we have a better idea how to assign these numbers. now lets take some measurements. lets say our point on the string moves 2 points towards the ceter generally north making it +3 the two points adjacent to our point also have to move they will have a value of -2 respectivily as they move in a generally opposit direction of the whole. (polarities with change as our point continues to move). we have -2 +3 -2 on our string, or one half of a complete wave, as it moves it becomes +2 -3 +4 -3 +2 now we have a comple wave diminishing as a gravitation wave should. but wait, so we can modle gravity this way, what else does the experiment show us? becouse our points are attached to each other what one point does has a "magnetic" effect on the points around it. Something else also happens, as our point moves inward, the entire string and all points on it are changed to 2s - and + so the entire system reduces in size, but now contains more information. as our point moves inward and the system gets more and more complex we see interesting formulas, atoms coverted to waves. there is yet another anomoly, (which we would probably not concider an anomoly) since the string is solid (we will assume unbreakable) it has tensil strength, the "stretch" of the string would be so small as to be almost impossible to calculate, but effectively our points move toward and away from each other in extreamly minute levels, this is "weak energy" . as the string creates ever more complex waves, its "area" gets smaller and smaller, giving the string the overall appearance of "shrinking" However we know there is the same amount of "mass" that we started with, now is you were a microscopic being "created" by these waves, the "shrinkage" would appear to be expansion to you. why? as the string system shrinks in on itself, the wave patters get smaller and smaller. lets say there is a "harmonic wave pattern" in the string, as that section of string moves inward the patters doesent change, it simple reduces in size, and neccisarily it reduces faster than the whole to maintain the integrity of the string.

    Now multiple that test to a google to the google power and again to the google power and we have a system of self promoting harmonic waves that take on the semblace of nuclei, and then more complex atoms, and compounds, acids, amobea, life.

    what is the string? it is a single super-string of Photonic energy.
    Why doesent the photons seperate from each other? becouse there is only 1 photon.
    How can one photon be the substance of all things? either it is super-luminal and able to be in all places at all times, OR it is absolutly still on a 5th dimensional plain.

    there is alot of stuff i havent mentioned here, either it would take to much to explain or too much to type. But i have simlated the expiriment on the computer (well not me, but a friend) and we came up with some very interesting calculations, like a carbon type wave that seemed to perpetuate itself. wierd stuff. anyway, that is a very very basic idea of my theory.

    Last edited: Apr 7, 2004
  19. Apr 7, 2004 #18
    its late and my spelling is terrible, forgive me
  20. Apr 7, 2004 #19
    Does the photon (electron) not satisfy both the conditions specified?

  21. Apr 7, 2004 #20
    Kaluza-Klien Theory

    Kaluza-Klein theory is a model which unifies classical gravity and electromagnetism. It was discovered by the mathematician Theodor Kaluza that if general relativity is extended to a five-dimensional spacetime, the equations can be separated out into ordinary four-dimensional gravitation plus an extra set, which is equivalent to Maxwell's equations for the electromagnetic field, plus an extra scalar field known as the "dilaton". Oskar Klein proposed that the fourth spatial dimension is curled up with a very small radius, i.e. that a particle moving a short distance along that axis would return to where it began. The distance a particle can travel before reaching its initial position is said to be the size of the dimension. This, in fact, also gives rise to quantization of charge, as waves directed along a finite axis can only occupy discrete frequencies.

    http://wc0.worldcrossing.com/WebX?50@198.JNLJbSiyQBd.0@.1dde6908 [Broken]
    Last edited by a moderator: May 1, 2017
  22. Apr 7, 2004 #21


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    In string physics the circle comes in in two ways: there is the closed string, which forms a loop, and which is analytically equivalent to a circle. Then there is compaction of a dimension on a circle, Kalusza-Klein style. This latter leads to interesting physics like T-duality, where the physics of tiny R, the radius of the compacted circle, is the same as the physics of huge 1/R, the reciprocal of that tiny number.

    If you map a closed string (one circle) into a circular compacted dimension (another circle), then the mapping will be characterized by a topological invariant, the winding number. Just the number of times the first circle goes around the second.
  23. Apr 7, 2004 #22
    In support of these statements then we would find Greene's statements as valid expressions of what can exist in any point?

    The familiar extended dimensions, therefore, may very well also be in the shape of circles and hence subject to the R and 1/R physical identification of string theory. To put some rough numbers in, if the familiar dimensions are circular then their radii must be about as large as 15 billion light-years, which is about ten trillion trillion trillion trillion trillion (R= 1061) times the Planck length, and growing as the universe explands. If string theory is right, this is physically identical to the familiar dimensions being circular with incredibly tiny radii of about 1/R=1/1061=10-61 times the Planck length! There are our well-known familiar dimensions in an alternate description provided by string theory. [Greene's emphasis]. In fact, in the reciprocal language, these tiny circles are getting ever smaller as time goes by, since as R grows, 1/R shrinks. Now we seem to have really gone off the deep end. How can this possibly be true? How can a six-foot tall human being 'fit' inside such an unbelievably microscopic universe? How can a speck of a universe be physically identical to the great expanse we view in the heavens above? (Greene, The Elegant Universe, pages 248-249)

    You know I hang onto the idea of Liminocentric structures.:)

    Here is a nice picture to consider.

    http://www.mncs.k12.mn.us/physics/string/string_artistic2.jpg [Broken]

    http://www.mncs.k12.mn.us/physics/string/string_index.html [Broken]

    Could you tell me why the image function is not activated in this forum? If it is a copyright issue, allow picture to be directly linked to its source. Would this be suitable?
    Last edited by a moderator: May 1, 2017
  24. Apr 7, 2004 #23
    i think probably my theory is a little misunderstood 8)

    kalusza also infers the the application of many of such "strings"
  25. Apr 7, 2004 #24
    why must we assume that there is some "barrier" outside the string circle?
  26. Apr 7, 2004 #25
    Because the string is relative.
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