Untying the Knot

Human beings have an unquenchable thirst for knowledge and an urgent drive for understanding. The further we go on our quest for absolute truth and the deeper we plunge into the heart of the ultimate reality, the more profound our questions become. Could there be something more to this world of ours than that which meets the eye? Is there some elaborate design behind the infinite galaxies, stars, and planets, or are we simply at the mercy of a chaotic and unordered universe? What is it that has given rise to the mysterious and unexplainable phenomenon that we have labeled the cosmos? Throughout history, we have attempted to answer these perplexing and ineluctable questions through myths, religion, or science. Apparent in many of these explanations is the idea of a unity, the "One", or a single entity that comprises all of reality. To some, it is God's presence. To others it is the Tao or simply "that which is, and, in the case of modern physics, it is infinitesimally small strings, oscillating and vibrating, like the strings of a violin, that comprise the fabric of our universe and "rhythmically beat out the laws of the cosmos" (18).

String theory is a revolutionary way of explaining the complexity of the cosmos. It is the unified theory of physics that Einstein searched for but never found. It forces us to look at the world in which we live in a drastically different and beautiful way. String theory states that all aspects of our universe consist of infinitesimally small, vibrating loops of energy (14). Like Pythagoras' idea of the "music of the spheres", these universal strings vibrate and oscillate, producing different notes in a cosmic symphony. Strings are the most basic constituents of matter, "atoms" in the true sense of the word. According to physicists, string theory may hold the key to understanding the inner workings of the universe. As Brian Greene states in his book The Elegant Universe:

String theory has the potential to show that all of the wondrous happenings in the universe--from the frantic dance of subatomic quarks to the stately waltz of orbiting binary stars, from the primordial fireball of the big bang to the majestic swirl of heavenly galaxies--are reflections of one grand physical principle, one master equation (5).

String theory is the first theory able to combine the undeniable, yet conflicting truths of Einstein's general theory of relativity and the newly emerging field of quantum mechanics. String theory has become the Holy Grail of physics. In it lies the possibility to finally unify all aspects of the universe as we know it and bring us to the end of our journey in the quest for the "theory of everything" (16).

The ancient Greeks made an amazingly insightful and accurate assumption that all matter is comprised of diminutive and "uncuttable" particles they called atoms (7). 2,000 years later, scientists have found that all matter is, in fact, comprised of basic elements, like oxygen and carbon, but they soon found out that even they were not the most basic constituents of matter (7). By the early 1930s, various scientists had discovered that "atoms consist of a nucleus that consists of protons and neutrons and is surrounded by a swarm of orbiting electrons" (7). Then, in 1968, even smaller components of protons and neutrons were found, the up-quark and down-quark (7). Since then, scientists have continued to slam bits of matter together, discovering new fundamental particles ranging in size from the smallest, ghostly neutrino that weighs less than 10^-8 (in multiples of the proton mass) to the largest top quark (8). Each of these particles also has an antiparticle partner (8). All matter encountered to date is comprised of a combination of these basic particles.

Scientists have also discovered particles that account for the four fundamental forces that act upon matter (10). The most familiar force to humans is gravity. The smallest constituent of this force is the graviton which has a mass of 0 (11). The next familiar of the four, the electromagnetic force, is carried out by the photon (11). This is the driving force behind lights, computers, televisions, and lightening (10). The strong force, responsible for keeping quarks glued together inside protons and neutrons and keeping protons and neutrons packed together in atomic nuclei, is exerted by the gluon which has a mass of 0 (11). The weak force and its particle the weak gauge boson is the force that is responsible for the radioactive decay of substances such as uranium and cobalt (11). Unlike the other forces, the weak gauge boson has a mass of either 86 or 97 (11). While scientists have been able to carefully measure the properties of these basic constituents of matter, the numerical input is completely arbitrary. There is no explanation for why the particles have the properties they do (12). String theory claims it has the answer that will finally explain the seemingly random properties of the elementary particles.

String theory has come a long way on a long and tumultuous path to recognition in the scientific community. It began in 1968 when theoretical physicist Gabriele Veneziano came upon a striking revelation while trying to understand the nuclear strong force (136). He found that a 200-year-old formula created by Swiss mathematician Leonhard Euler (the Euler beta function) perfectly matched modern data on the strong force, but no one could understand why it worked (137). This changed when Yochiro Nambu, Holger Nielsen, and Leonard Susskind unveiled the physics beneath Euler's strictly theoretical formula two years later (137). By representing nuclear forces as vibrating, one-dimensional strings, these physicists showed how Euler's function accurately described those forces (137).

The scientific community slowly lost interest in string theory when its description of the strong force made predictions that directly contradicted experimental findings (137). At the same time, the point-particle quantum theory of chromo dynamics exhibited overwhelming success in describing the strong force, and so the standard model remained unthreatened (137).

Then, in 1974, John Schwarz and Joel Scherk studied the messenger-like patterns of string vibration and found that their properties exactly matched those of the gravitational force's hypothetical messenger particle (138). Schwarz and Scherk argued that string theory had failed to catch on because physicists had underestimated its scope (138).

Still, their work was ignored by the physics community because the conflicts between quantum mechanics and string theory remained unresolved (138). 1984 was a turning point for string theory. John Schwarz and Michael Green declared that string theory was not a strong force theory, but rather a

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