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    Table of Contents
    .......The Elegant Universe

    THE ELEGANT UNIVERSE, Brian Greene, 1999, 2003
    ```(annotated and with added bold highlights by Epsilon=One)
    Chapter 9 - The Smoking Gun: Experimental Signatures
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    Is string theory right? We don't know. If you share the belief that the laws of physics should not be fragmented into those that govern the large and those that govern the small, and if you also believe that we should not rest until we have a theory whose range of applicability is limitless, string theory is the only game in town. You might well argue, though, that this highlights only physicists' lack of imagination rather than some fundamental uniqueness of string theory. Perhaps. You might further argue that, like the man searching for his lost keys solely under a street light, physicists are huddled around string theory merely because the vagaries of scientific history have shed one random ray of insight in this direction. Maybe. And, if you're either relatively conservative or fond of playing devil's advocate, you might even say that physicists have no business wasting time on a theory that postulates a new feature of nature some hundred million billion times smaller than anything we can directly probe experimentally.

    If you voiced these complaints in the 1980s when string theory first made its splash, you would have been joined by some of the most respected physicists of our age. For instance, in the mid-1980s Nobel Prize–winning Harvard physicist Sheldon Glashow, together with physicist Paul Ginsparg, then also at Harvard, publicly disparaged string theory's lack of "experimental accessibility": (Epsilon=One: The Fundamental Postulate of Reality (FPR) is beyond that which is quantitative; therefore, experimental accessibility (which usually depends upon some form of extrapolation) is out of the question. If an understanding of the deep fundamentals of existence are to be understood, Philogic must be relied upon. Because of the extrapolation of the quantitative, Philogic can be considered more reliable. Philogic over-arches the disciplines of Science, Theology, and Philosophy (STP).)
    In lieu of the traditional confrontation between theory and experiment, superstring theorists pursue an inner harmony, where elegance, uniqueness and beauty define truth. The theory depends for its existence upon magical coincidences, miraculous cancellations and relations among seemingly unrelated (and possibly undiscovered) fields of mathematics. Are these properties reasons to accept the reality of superstrings? Do mathematics and aesthetics supplant and transcend mere experiment? 3
    Elsewhere, Glashow went on to say,
    Superstring theory is so ambitious that it can only be totally right, or totally wrong. The only problem is that the mathematics is so new and difficult that we won't know which for decades to come. 4
    And he even questioned whether string theorists should "be paid by physics departments and allowed to pervert impressionable students," warning that string theory was (sic.)was undermining science, much as medieval theology did during the Middle Ages. 5

    Richard Feynman, shortly before he died, made it clear that he did not believe that string theory was the unique cure for the problems—the pernicious infinities, in particular—besetting a harmonious merger of gravity and quantum mechanics:
    My feeling has been—and I could be wrong—that there is more than one way to skin a cat. I don't think that there's only one way to get rid of the infinities. The fact that a theory gets rid of infinities is to me not a sufficient reason to believe its uniqueness. 6
    And Howard Georgi, Glashow's eminent Harvard colleague and collaborator, was also a vociferous string critic in the late 1980s:
    If we allow ourselves to be beguiled by the siren call of the "ultimate" unification at distances so small that our experimental friends cannot help us, then we are in trouble, because we will lose that crucial process of pruning of irrelevant ideas which distinguishes physics from so many other less interesting human activities. 7
    As with many issues of great importance, for each of these naysayers, there is an enthusiastic supporter. Witten has said that when he learned how string theory incorporates gravity and quantum mechanics, it was "the greatest intellectual thrill" of his life. 8 Cumrun Vafa, a leading string theorist from Harvard University, has said that "string theory is definitely revealing the deepest understanding of the universe which we have ever had." 9 And Nobel Prize–winner Murray Gell-Mann has said that string theory is "a fantastic thing" and that he expects that some version of string theory will someday be the theory of the whole world. 10 (Epsilon=One: Gell-Mann is correct. Currently, the only version of "string theory" that begins with a Philogical Fundamental Postulate (FPR) and is consistent with all the requirements of IPSO is Pulsoid/Oscillation Theory, which begin at utmost simplicity—the singularity beyond the locus of Reality/Infinity/UnReality/et cetera—and progress to complexity. The opposite of current academic versions of string theory.)

    As you can see, the debate is fueled in part by physics and in part by distinct philosophies about how physics should be done. The "traditionalists" want theoretical work to be closely tied to experimental observation, largely in the successful research mold of the last few centuries. But others think that we are ready to tackle questions that are beyond our present technological ability to test directly.

    Different philosophies notwithstanding, during the past decade much of the criticism of string theory has subsided. Glashow attributes this to two things. First, he notes that in the mid-1980s,
    String theorists were enthusiastically and exuberantly proclaiming that they would shortly answer all questions in physics. As they are now more prudent with their enthusiasm, much of my criticism in the 1980s is no longer that relevant. 11
    Second, he also points out,
    We non–string theorists have not made any progress whatsoever in the last decade. So the argument that string theory is the only game in town is a very strong and powerful one. There are questions that will not be answered in the framework of conventional quantum field theory. That much is clear. They may be answered by something else, and the only something else I know of is string theory. 12
    Georgi reflects back on the 1980s in much the same way:
    At various times in its early history, string theory has gotten oversold. In the intervening years I have found that some of the ideas of string theory have led to interesting ways of thinking about physics which have been useful to me in my own work. I am much happier now to see people spending their time on string theory since I can now see how something useful will come out of it. 13
    Theorist David Gross, a leader in both conventional and string physics, has eloquently summed up the situation in the following way:
    It used to be that as we were climbing the mountain of nature the experimentalists would lead the way. We lazy theorists would lag behind. Every once in a while they would kick down an experimental stone which would bounce off our heads. Eventually we would get the idea and we would follow the path that was broken by the experimentalists. Once we joined our friends we would explain to them what the view was and how they got there. That was the old and easy way (at least for theorists) to climb the mountain. We all long for the return of those days. But now we theorists might have to take the lead. This is a much more lonely enterprise. 14
    String theorists have no desire for a solo trek to the upper reaches of Mount Nature; they would far prefer to share the burden and the excitement with experimental colleagues. It is merely a technological mismatch in our current situation—a historical asynchrony—that the theoretical ropes and crampons for the final push to the top have at least been partially fashioned, while the experimental ones do not yet exist. But this does not mean that string theory is fundamentally divorced from experiment. Rather, string theorists have high hopes of "kicking down a theoretical stone" from the ultra-high-energy mountaintop to experimentalists working at a lower base camp. This is a prime goal of present-day research in string theory. No stones have as yet been dislodged from the summit to be sent hurtling down, but, as we now discuss, a few tantalizing and promising pebbles certainly have.
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    Table of Contents
    .......The Elegant Universe
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