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Strings Most Fundamental Elements?

  1. Apr 23, 2004 #1
    Most Fundamental Elements?

    Science continues to discover more fundemental elements with which to govern its predictions on and to unite a wider breadth of the universe. The latest, string theory, posulates, in laymens terms, that there are even smaller elements governing all aspects of our Universe and unifying the forces.

    But why does it end there? It doesn't require a leap of faith to believe that this cycle would be infinite, each element being built on more fundamental elements (time and all forces simply being one of these) down to an infinitely identical ether. This is mere philosophy at a certain scale, but when we're dealing with near-singularities such as the big bang or black holes this would suggest an absolute physical model would be infinitely complex to solve. That is, if each element is governed by constituent elements you could only ever hope to model them at a certain level of inaccuracy and abstraction, one that would consistently break down beyond a certain scale of observation.

    Is this view held by any credible astrophysicists? If not, why not?
     
    Last edited: Apr 23, 2004
  2. jcsd
  3. Apr 24, 2004 #2
    I'm not sure that homogeneity is necessary for a successful ontology.
     
  4. Apr 24, 2004 #3
    The question of homogeneity is not one of necessity but abstraction. Why would there be a limit on elemental fundamentality? Such a concept is too ugly for me to believe. Belief aside, why on earth would this limit be at a level we could ever theorize about?
     
  5. Apr 24, 2004 #4
    String theories are not the only candidates for a theory of everything,loop quantum gravity is another very interesting proposal for a quantum gravity theory.Moreover given that string theories are background dependent (no model of spacetime itself proposed) some believe,Lee Smolin,for example that only a mixture of those two could eventually lead to a successful 'theory of everything'.

    One of the main characteristics of science is that in the vast majority of cases (and surely in physics) we can never establish whether our theories are exact models of reality or at least the best theories possible.Thus all our accepted knowledge acquired using the most successful method known so far is always provisional,the actual epistemological priviledge of science being itself provisional.Even if string tentative theories will ever become full part of science (still not the case now for reasons I will present below) the ultimate nature of 'what there is' will still be an open problem;indeed even if strings are postulated to be the ultimate constituents of reality in the ontology proposed by the theories using them scientists will remain open to doubt,providing sufficient arguments even smaller particles will be introduced in our scientific models.Science,whatever the method proved to be the best at a certain moment in time,will make only epistemological (fallible,based on the principle of sufficient reason) assumptions,there are slight chances to realize whether there exist an infinite regression or that a certain (successful at a certain moment) proposed ontology is indeed the ultimate ground of all that is (though in reality it might very well be).

    Few words about the homogeneity of the accepted enunciations about the world (nature).The actual experience we have show that new theories introducing 'deeper' concepts such as atoms and so on have accomplished also a huge concentration of explanation for phenomena considered once as being totally distinct.So was the case with the atomic hypothesis,quantum mechanics or quantum electro[weak] theory (unfying almost all interactions known less gravitation) and the same will be the case with string or loop quantum gravity theories if ever successful.Thus there is a high degree of coherence between different parts of science and between newer theories and the older ones (the new versions regain the successful predictions of the older ones at limit).No matter why logic can be applied to reality (there is no proof that it should,as Einstein observed the deepest mistery is why do we understand something about nature at all) since there is no equally successful alternative view where large chuncks of accepted knoweldge (inferred using the principle of sufficient reason) to be replaced,showing also the same degree of coherence,there is basically no reason to believe now that other scientific programmes using ad hoc (non homogeneous with the main body of accepted scientific enunciations) could ever prove more successful.


    I was saying that there are problems with string theories.Indeed though they do make new ('forward') predictions apart from accomodating observed facts at our level they are basically irrefutable.Lee Smolin for example argues,on good reason,that all the variants existing today have adjustable parameters which can be always modified to fit the experimental data.Even in the extreme case that an unifiying theory (the M theory) would be found eventually.This make them quasi irrefutable,not far from psycho analysis.The difference is of course that they still make new ('forward') predictions.At limit we can accept them as scientfic hypotheses,though only in a weaker form,simply because they make new potentially testable predictions.Indeed it is conceivable that one of the variants could prove to be a theory of everything,the use of falsifiationism in the problem of demarcation between science and non science is not always relevant.

    It will be very interesting the follow the evolution of string theories,scientists are confident we will be able to test their new predictions soon.Indeed it is very likely that the new european collider will provide them the first chance to test string theories soundly.But even if they will be disproved I do not think it will be a tragedy.By changing some of the auxiliary assumptions in the premises (adjust some parameters) the most probably we could obtain a theory capable to explain the results of the experiments making also new predictions,not tested yet.Such a theory is theoretically evolving.However the crucial question appears next: will those predictions be corroborated later?If not we will be even outside the lakatosian definition of what is scientific not the mere popperian one.It is absolutely necessary to corroborate first at least one of those new predictions before a possible disproval of another prediction.Indeed if the new predictions are not confirmed the theory is not experimentally evolving and if we must ever adjust some parameters in the premises without any new prediction confirmed later (corroborated)...Basically would be present all the conditions put forth by Popper to consider it not scientific.Still,as I've argued before,some variation of the theory might really provide a theory of everything...That's why,even in the case presented above,I think it's safer to consider string theories scientific as much as new predictions,potentially testable,are made (in other words the theory is at least theoretically evolving).
     
    Last edited: Apr 25, 2004
  6. Apr 24, 2004 #5
    Here is an argument for there existing simple objects - objects which are indivisible, are not constituted by anything more fundamental.

    A fact - a state of affairs - is a complex, it is the concatenation of objects into a particular form. Let's suppose that objects are not simple, they are complex. In that case, they must be a concatenation of other more primitive objects. And so on, ad infinitum. We have an infinite regress of states of affairs being nested inside one another. We don't actually have any objects. But it is the nature of a state of affairs to be constituted by objects, so if there are no objects, there are no states of affairs, so there is no world (no totality of states of affairs). So it seems that there must be simple objects.

    There are obviously problems with this argument - for instance, why can't we collapse states of affairs with complex objects - but I think asking whether there should be a limit on elemental fundamentality (as you put it) is an empirical question, not a logical question.
     
  7. Apr 24, 2004 #6
    If a state is a complex it by your definition requires constituents. How then can there exist a fundamental element exhibiting state? This is far more troublesome a premise than that of infinite granularity.
     
    Last edited: Apr 24, 2004
  8. Apr 25, 2004 #7
    Well, the diameter of a string is equivalent to that of the Planck Length, the smallest size matter can theoretically assume: 10-33. This to my understanding is so because it is the smallest theoretical size at which matter can be focused into the smallest point in space without collapsing.

    To learn more about the mathematical explanation for the Planck Length, please visit the following page at the following address : http://www.math.ucr.edu/home/baez/planck/node2.html
     
    Last edited: Apr 25, 2004
  9. Apr 25, 2004 #8
    Stevo, a good post.
    Indivisibility is indeed an important and fundamental concept. IMO it is related to interconnectivity, which is the fundamental question in physics.

    If you believe a TOE is possible, you have to answer the question: What is 'one' but at the same time 'many separated objects or processes'?.

    There is only one phenomena in physics that expresses interconnectivity. What proven and measured process connects in a dynamic way and indivisible way everything with everything?
    We call that 'gravity'. But another new name may be better since we associate gravity to much with falling apples, maybe we should call that inter-elasticity or inter-stress or something like that.

    The logic problem with cosmology and physics is that we try to combine 'gravity' with separated 'gravitons'. The cause of a separation approach is that everything we see in our 3D reality is separated in 'apparent' individual units. That makes believe most scientists that 'separation' is a fundamental principle.
    But of course gravitons will need also to be connected with each other. So we push the fundamental question about interconnectivity to a further - more deeper - level. We try to locate the concept of interconnectivity on separated spots (graviton particles). In string theory the same thing happens: there are a lot of strings. Separated again. And the real solution will be found in about 50 years. So we push the answer to the future. We accept that in the NOW we don't have the answer. No good.

    The good thing about strings is that the concept includes a deeper level of dynamics. Don't forget that strings were first called: Rubber bands!

    Rubber bands: that's very interesting! Why? What unities all those separated rubber bands? Rubber. Elasticity.
    Looking for a TOE you must say: The hidden background - uniting all those strings - has thus an elastic property.
    Since we have a traditional name for the background: Space-time, we can say that spacetime has an elastic property, not a fixed framework. We can say also that such an elastic spacetime may be called a membrane or brane.

    Nice. And indeed there is concatenation of other more primitive objects which bring complex 'objects'.

    The next step is to explain how that elastic membrane may create 'separate' strings or 'events'. How does the single elastic membrane creates "locally" various rubber bands, like 'red rubber bands, green rubber bands, blue rubber bands, and ... these can combine to red with blue rubber bands, blue with orange, (blue-pink) with (yellow-fuchia-red-blue), etc. ... to highly complex combinations? That's concatenation.
    So how: M (the membrane) = x (red rubber bands) + y(blue strings) + z(various colors of rubber bands) + rest of M (not manifested in rubber bands = the potential of the membrane to manifest itself in new rubber bands).
    The fundamental question about 'interconnectivity is solved in such concept: Because every local rubber band is part (sub-set) of the membrane. Moving one rubber band will influence all other rubber bands (strings) + all positions on the whole membrane. Isn't that what we call GRAVITY? When we call that inter-action 'gravity' we understand that a cosmic game is a giant push-and-pull system and a continuos dynamic feedback system.

    The more rubber bands combine to highly complexities the more they get dense (less elastic) and get higher mass. The essence of our reality is thus that everything is re-structured membrane.

    You can find more details and the engineering picture to get to that on my webpage: http://www.mu6.com/holon_creation.html.

    dirk
     
    Last edited: Apr 25, 2004
  10. Apr 25, 2004 #9
    From this converation, I would wonder then how we would have applied the issues of time?:)

    Pelastrian's mention of the rubber bands quickley brought Susskind to mind.

    But if one looks to this quantum level how shall we measure time? At planck length and Planck time, we have to set aside the realization that such reductionism as we have curently known has to be given a new structure for consideration?

    We know dynamical events are going on in the cosmo and one way to see this would be in a pelastrian sense. By what value should we then align clocks in this dynamical sense?

    This then goes deeper to the realization of "something else," that would separate the instantaneous feature of what is realized in spooky action at a distance? What value could be assigned between the great distances in space, if such a feature is realized in time?


    The gravitational wave, now as a graviton recognizes the diversty of dimension( one may look at solition wave production here and the boat )? How then has time become a new factor in the significance of this distance to have realized that 15 bilions years can be measured in any now?

    LIGO realizes this. Imagine this wave affecting the interferometer. What has this great distance realized? If it is measured "now" there is no separation from the event?
     
    Last edited: Apr 25, 2004
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