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If a historian from the future were to write the history of science of the twenty century, he would not doubt be astonished by the names and their accomplishments. In the atomic realm alone, the list is extensive. In 1902, Lord Kelvin put forward the first model of the atom.

In 1910 J.J. Thomson identified protons. In 1911 Ernest Rutheford discovered that atoms consisted of a tiny central nucleus which was somehow surrounded by a cloud of electrons. In 1913, Niels Bohr completed the first model of the atom that took into account the implications of quantum. In the 1920's, working separately, Heisenberg and Schrödinger systematized quantum and Bohr presented his Copenhagen interpretation. George Gamow presented a model where the atomic nucleus resembled a drop of liquid held together by a sort of surface tension. In 1932 James Chadwick discovered the neutron, a particle with no electric charge and the same mass as the proton and John Cockroft with Ernest Walton used the first particle accelerator to split the atom. While in less than 40 years particle physics did not merely revolutionize itself but both our conception of our physical world and the technologies that surround us, astrophysics managed to up the ante as far as progress is concerned. Astrophysics watershed year might be 1915, when Einstein presented his general theory of relativity to the Prussian academy of science, describing what happened when the space-time was distorted by the presence of matter. By 1916, the implications of Einstein's general theory began to branch out and a myriad of theoretical up-shots are postulated, among them worm and black holes, and the expansion of the universe. In 1919, one of the first physical confirmation to one of the predictions of general relativity is obtained when the bending of light caused by the gravity of the sun was measured. The story goes that Max Plank stayed up all night awaiting the results. To this, Einstein replied: "he didn't really understand science...if he had really understood the way the general theory of relativity explains the equivalence of inertial and gravitational mass, he would have gone to bed." ^{[ Note 1 ]} In the 20's, more and more predictions were being matched. The most startling was Edwin Hubble's discovery that the Milky Way was one galaxy among many in a cosmosthat was expanding. The discovery of the expansion of the universe did not merely confirm some of the predictions which relativity had put forth but confirmed relativity's most stunning prediction, that the universe had had a birth. By the 1940's George Gamow and Ralph Alpher were attempting to describe the conditions of the big bang quantitatively, investigating the kind of nuclear interactions that would have occurred at the birth of the universe.

If our historian from the future looked at Gamow's and Alpher work he would deduce that it prefaced two things. First it lay the ground what was to become the central scientific concerns to physicists in the latter half of the twenty century. Second, as many such concerns do, the work that went into resolving it, while in many way brilliants, seemed more like a standstill. Our historian perhaps would change the tone of his narrative from triumphal and exultant, to ironic and defeatist. He would perhaps write: "While Gamow's work shed light on the possible new paths that physics was going to take, it also set a holy grail which physicists aspired to. Like all holy grails, this one proved elusive. There were many false starts. There were many unavailable technologies. But most important, the goal proved impossible because of two things, internal conflicts and dogmatism. Despite their believe in symmetry and simplicity scientists resorted to elaborate schemes and refused to allow common sense when it was time for science to allow common sense back into its methods. Furthermore, they were blind or constrained by their method and failed to see the obvious clues towards the attainment of their goal."

Our imaginary historian from the future would, of course, be, like historians from every age, speaking with the benefit of hindsight, which we know, has a vision of 20/20. The question, however, is why would he offer such dismal view of physics in his account of the latter half of the twenty century. After all, both particle physics and astrophysics have made tremendous advances. The latter is on the verge of figuring the value of omega the number that will determine the amount of matter in the universe and which will tell us whether the universe will keep expanding indefinitely or whether it will eventually collapse. In 1998, it also made news with the discovery of lambda, an unsuspected new force that controls the expansion of the universe. Particle physics on the other hand, has become an intrinsic part of our lives. Even though most people might perceive it as a puzzle for academics in their ivory towers, quantum has transformed the way we live in every way, from the most trivial to the most commercial. In the domestic realm, our TVs and CD players and CD-ROMs could not exist without quantum. TV, Hi-fi, and car depend on semi-conductors, materials with conducting properties that lay between insulators and conductors and where electrons can hop from one atom to the next under the right conditions. This hopping from atom to atom depends on a series of quantum rules known as Fermi-Dirac statistics. Without them, no one would have been able to design the fast computers we have now. Of course, we can see both computers, CDs and TV as merely trivial. Civilization managed without them for millennia. Are they really that important? Quantum is embedded in nature though, so understanding it has also allowed us to understand not mere inanimate behavior but phenomena without which our existence would not be possible. Because of quantum uncertainty, we understand how in the sun, our only source of energy, allows hydrogen nuclei to fuse together and generate heat. Because of quantum too, we understand how the DNA molecule replicates itself. Life on this planet largely depends on the DNA molecule's ability to 'unzip' itself and make two copies of the original double helix by building up a new partner for each strand of the original molecules, using each unzipped single molecule as a template. The links that are used in this process to hold the strands together most of the time but which also allow them to unzip when it is necessary or appropriate, are a kind off chemical bond known as the hydrogen bond. The hydrogen bond, a single proton is shared between two atoms and forms a link between them. In short, quantum explains the central mystery of life through the quantum process that is at the heart of hydrogen bonded systems.

So, if both astrophysics and particle physics have made such advances and given us a much deeper understanding of the world we live in, then why our imaginary historian's complaints? The path that Gamow and Alpher began in the 1940's was the path towards what is known as the theory of everything. Not to be confused with grand unified theories, which only attempt to combine the description of the electromagnetic force, the weak nuclear force and the strong nuclear force in one mathematical package similar to the one James Clerk Maxwell found to unify the electric and magnetic force, the theory of everything or TOE attempts to throw gravity into the package. In other words, a TOE would, if ever developed, explain electro-magnetism, the weak and strong nuclear forces and gravity under a single mathematical rubric. There are many hurdles to overcome for any such theory to ever emerge. However, in the following chapters, in the second half of this book we will argue that more than mathematical models or technology, what seems to obstruct the way is scientists' dogmatism, their inability or unwillingness to think creatively and outside academic or institutional articles of faith. This dogmatism is at is most blatant when we find scientists who are stigmatized for their ideas. Bohm, whose ideas we touched upon in the last chapter was just one of these scientists. Teilhard de Chardin, whose ideas will dominate the second half of this book, is not merely another example, but the archetype of the spurned scientists. We will return to both Teilhard de Chardin and Bohm because at the heart of his hidden variables as well as his exploration of the nature of consciousness is akin to Teilhard de Chardin. First though we will isolate what has surfaced as the two main contenders for a successful theory.

Scientists believe in symmetry and simplicity. To many Paul Dirac's famous remark that "it is more important to have beauty in one's equations than to have them fit the experiment" is precept ^{[ Note 2 ]}. The numbers by which they understand the world have to represent, not the unstable and chaotic elements in nature but the stable ones. In other words, their formulas quantify phenomena which remains stable through transformations. To understand how this is so and what is meant by symmetry, let us imagine that the known world which scientists study is a text, let's say that Dante was right and his Thomist cosmology is the correct one. Let's imagine scientists would attempt to understand the innermost workings of that text. The first thing that they might try as they feed each line of the poem into their super computer is to tabulate the different patterns that appear. Very quickly, as soon as the whole text, Hell, Purgatory and Paradise have entered, they will know that the one hundred cantos are made up of permutations of 25 letters. The discovery of these 25 letters would not be unlike coming up with what we know as the standard model of quantum mechanics. The scientists have found a tiny symmetry: something that remains constant despite permutations. The discovery, however, barely explains the depths and scope of the text that they just typed into the computer. So their next task is to find if these 25 elements, these 25 letters are arranged into some kind of pattern. The computer will, of course, be quick at doing the sort of job that took linguists centuries. It will find morphemes and phonemes, prefixes and suffixes. It might not understand the way by which letters become semantic, but patterns there will be and our imaginary scientists would have had discovered words. Again, despite the different terrains in the cosmology of the text, the frozen rivers of hell or the steep cliffs of purgatory, that one constant of that world is that is made up of meaningful units. And whereas the meteorological contrast from one region of that universe to the next might be asymmetrical, the fact that each region is made out of words points out a symmetry. As our scientists hail the discovery, they know there is work to be done if they are to understand how this world really functions. Words are a major discovery, but do this words follow a pattern? The disks of supercomputer might stutter and stumble a bit more here, but eventually it has a breakthrough: certain types of words appear to have certain functions and to take a certain place in the poem. The scientists would have discovered what generative linguists did in the latter part of this century, a generative syntax and grammar. Eventually the computer will also discover the poem's meter and rhyme scheme as well as its overall design. And once the scientists have accounted for all this things that are symmetrical -that happen in equal parts or measures, to recur to the word's original meaning- then they will have a deeper understanding of Dante's world. After all their research, however, there will remain chaotic elements, asymmetrical elements, elements that have no patterns or recurrence.

Just as our imaginary scientists broke Dante down, real scientists look at the different phenomena in nature to find patterns. During this century, scientists faith in symmetry has only strengthen as they realize that each force or law that they have discovered is applicable anywhere in the universe. Like Dante's text, governed by the laws of language and organized by meter and rhyme, particles everywhere have the same characteristics and are subject to the same laws. This sort of symmetry, which argues that the laws of nature are the same anywhere in the universe is known as transitional invariance and corresponds to the law of conservation of linear momentum.

Central to this faith in symmetry and to the breaking down of symmetry in the scientists' scheme of things are the four forcer of nature. The two with the longest range and more obvious effect in our large scale world are gravity and electromagnetism. The other two forces, the strong and weak nuclear forces only have a range within the atomic nucleus. Each of these forces seems so far to be so finely tuned, that if any of they values were just a tad greater or smaller, the universe as we know it would not exist. Gravity, despite the fact of being the most obvious to us, is the weakest force but was the first one to be understood in any kind of systematic way. We have dealt with this in the chapter when we dealt with Newton and Einstein. If we feel gravity more than the other forces, it is because unlike the other three forces, gravity is additive. Every atom that we pile into a mass contributes to the overall effect of gravity.

One strongest force by far is electromagnetism. However, neither electricity, nor magnetism add up the way gravity does. Electricity manifests itself through its charges, positive and negative; magnetism, through its poles, north and south. And since both poles and charges tend to cancel each other, this reduces the overall influence of electromagnetism. In electromagnetism we can see the small scale version of the attempts to come up with a theory of everything. Up until the nineteenth century, electricity and magnetism were understood as two different forces and their influence was understood through two separate formulas. In short, scientists understood electricity and magnetism like they do the four forces now: no single mathematical rubric encompassed their action. James Clerk Maxwell discovered a set of equations that described both electricity and magnetism in one package. This synthetic impulse is exactly the same that now guides physicists' attempts to find a TEO. It was the first successful attempt at unification and still inspires scientists to achieve further unification of the forces of nature, with the goal of finding one set of equations that will describe all the forces as facets of a single super-force.

Unlike gravity, electromagnetism holds sway in the small-scale regions, in the formation of molecule and atoms. In fact, electrons and nuclei in the atom are held together by electromagnetism. And electromagnetism is also the glue, so to speak, that holds molecules together. If a climber has to struggle up a rope against the very obvious force of gravity, what holds him from falling is the electromagnetic force which is stronger if not as obvious. Still, the rope is held together by electromagnetic forces which operate between neighboring atoms and molecules. If the rope would happen to snap because of the climber's weight, it is because the gravitational pull of the entire earth which contains 5.976x1024 kg of matter succeeded in breaking the electromagnetic bond between the few molecules of the rope.

Electromagnetism's sway is such, that unchecked, it would be capable of blowing the atom's nucleus apart. What prevents this is an even stronger force: the strong nuclear force. The strong nuclear force overpowers the electric repulsion on the scale of the nucleus. The strong force is about 100 times stronger than the electromagnetic one. Only lately has the strong nuclear force been understood as the manifestation of the deeper color force which operates between quarks within the protons and neutrons that make up the nucleus.

Every force, manifests itself through the exchange of messages to particles. And if the weak nuclear force does not resemble the other three forces at all, it at least does so in this fact. The range of the force is limited and its interaction takes place through messenger particles: namely, intermediate vector bosons. Like the consolidation of electricity and magnetism a century earlier, this century, Aldus Salam and Steven Weinberg, working independently, found a way to consolidate the weak interaction and the electromagnetic interaction under one mathematical rubric ^{[ Note 3 ]}.

Still the search for a super-formula, so to speak, a set of equations that will reveal how each of the forces interacts so that the inner-works of our world are understood is an unattained goal. The two theories that seem as the most possible candidates for the achievement of the goal so far are Super string theory and Super symmetry. We will too briefly for the complexity of both subjects deal with each of the theories and since both are truly beautiful mathematical models will also try to see how they hold against the world of fact. After all, despite Dirac contention that formula should be beautiful before it fits experiment, we should remember that there are beautiful conceptions that are not true.

Supper symmetry stemmed from the success of the gauge symmetry approach in understanding the forces and particles. In the 70's the major asymmetry was the distinction between particle and force, or fermions and boson respectively. The asymmetry as it was perceived then was not necessarily cosmetic but was a reflection on the spin of each entity. Supper symmetry solved the problem by attaching another four dimensions to the four dimensions of space. These dimensions are not like those that we will encounter as we look at Super string theory. Nevertheless, to be fair, Super symmetry's precepts are necessary for Super string theory to work.

Super symmetry unlike many of other theories did not arise from the need to solve a problem. Originally noticed as a property in certain models, scientists eventually understood that the theory could resolve a number of mysteries in particle physics as well as provide new approaches toward the solving of other puzzles. What mysteries did supper symmetry solve? Chiefly, the Standard model had a serious conceptual problem called a hierarchy problem. The natural scale for the primary theory is the Planck scale 10-35 meter. The Standard Model is a description of quarks and lepton in their interactions, at a scale of 10-17 meter. The problem is that the quantum theory, physics at one scale might contribute to physics at other scales, so it is not consistent to have those scales so separate. Instead, the quantum scale and the Planck scale should be very near each other. The problem really has two parts. First, given that there is a separation of the standard model scale from the plank scale, why does the Standard model end up where it is and not in another scale? The question probes at the depth of the Standard Model. Is the scale a random, man imposed model, or if is the standard model truly an elegant model? The latter question leads to the second problem: what can make the theory maintain the separation in a mathematically consistent way? The super symmetric standard model solves the second problem and gives insight to the first. It does so in a manner that uses the unification of fermions and boson, in an essential way. The very nature of fermions and bosons implies that they contribute to the coming together of scales in ways that cancel, so the mixing of scales can be cancelled in a general way.

Super symmetry's more important contribution toward solving those serious mysteries of physics has been its attempt to reach a TOE. As we have seen, for centuries physicists have been actively trying to unify our description of the forces of nature. Again, having five different forces instead of one basic force suggests that physics have not yet found the one basic unifying principle. In quantum theory, one could calculate how a force would behave if one would study it at smaller distances. Remarkably, when this is done at smaller and smaller scales with the strong and weak nuclear forces and with the electromagnetic force, these forces become all too similar. More remarkably, when the study is repeated with the formulas of the super symmetric Standard model, as was done in the 80's, forces become essentially equal at a very small distance, though nothing in the Standard model suggests that this should happen.

As we pointed out before, Super symmetry not only predates Super string theory but is a necessary condition for Super string theory to work. Super string, nevertheless is a much more effective theory in its attempt to unify the five forces. Like most theories which manage to succeed, Super string is elegant and almost too common-sense. Super strings resolves the split between forces and the discrepancies in atomic physics by postulating that the fundamental particles and their interactions are not points (or "particles"), not mathematical points, but strings and that matter and the forces as we know them are merely the manifestation of the different vibrations. The postulate of this strings resolves a lot of minor discrepancies. Nevertheless, the major contribution at the moment is the fact that as physicists look at the standard model through a Super string perspective, they are able to see how all forces are equal near the Planck scale.

In a latter chapter we will explore Super string theory in depth. For the moment suffice it to say that both Super string and Super symmetry theories are viable. And though we prefer the postulates of Super strings to those of Super symmetry, the reason why we think that both seem to be following the right path, why both are asking the right questions is because both make two very important points. First, they confirm what too many scientists would like to deny: the limit of our current scientific tools as well as the way in which the current approaches have to be revised. Both Super string and Super symmetry resolve discrepancies of physics to the point of unifying the five forces only at or below the Planck scale. Their solution, in other words will not be confirmed using the current methods and technology, since no super colider can muster the force to split the atom at Planck scale. By underscoring physics' experimental deficiencies, Super string also provides us with a universe where limits are important, a universe where there is a limit to time and to space, a universe where past that limit we would behold not necessarily a different reality, but a reality where the split world that physics describes is no longer split.

The question that arises, if the postulates of Super string theory undermine the tools and methods of particle physics: does it mean that there will be no way to confirm the theory and to prove that deep inside, nature is unified by an elegant and legible set of rules? Does it set, in other words, a terminus to science? For many, the answer is yes. For us, however, it is definite no. For us, Super string is merely the prism that concentrates the diffused light of five different forces, unifies it and then diffracts it so that the unification can be explained through other sciences, other theories. In the second half of the book we will be seeing possible alternatives.