Exactly What is String Theory?
String theory attempts to unify the four forces in the universe – electromagnetic, strong nuclear, weak nuclear, and gravity – together into one unified theory. When it was originally developed in the 1970s, the filaments of energy in string theory were considered to be one-dimensional objects: strings. (One-dimensional indicates that a string has only one dimension, length, as opposed to say a square, which has both length and height dimensions.) These strings come in two forms – closed and open. An open string has ends that don’t touch each other, while a closed string is a loop with no open end. It was eventually found that these early strings, called Type I, could go through five basic types of interactions.
The interactions are based on a string’s ability to have ends join and split apart. Because the ends of open strings can join together to form closed strings, you can’t construct a string theory without closed strings. This proved to be important, because closed strings have properties that might help define gravity. Instead of just being a theory of particles of matter, physicists began to realize that string theory might explain the behavior of particles relative to gravity. Gravity, in its most basic definition, is a force that tries to pull two objects toward each other. Simple enough, right? Anything that has mass also has gravitational pull. The more massive an object is, the stronger its gravitational pull. Earth’s gravity, for example, is what keeps us on the ground, and what causes objects to fall. It is true, by the way, that the Moon’s gravitational pull on the Earth affects tidal cycles of Earth’s oceans.
A Thought or Two About the Intelligence Behind Our Universe
The force of gravity is so universal that every particle feels it based upon its mass or energy. Gravity is the weakest of the four forces by a long shot; it is so weak that we would not notice it at all were it not for two special properties that it has: it can act over large distances, and it is always attractive. This means that the very weak gravitational forces between individual particles in two large bodies, such as the earth and the sun, can all add up to produce a significant force. It makes the earth revolve around the sun!
The electromagnetic attraction between negatively charged electrons and positively charged protons in the nucleus causes the electrons to orbit the nucleus of the atom, just as gravitational attraction causes the earth to orbit the sun. Even though it is very difficult to observe spontaneous proton decay, it may be that our very existence is a consequence of the reverse process, the production of protons, or more simply, of quarks, from an initial situation in which there were no more quarks than anti-quarks, which is the most natural way to imagine the universe starting out. Matter on earth is made up of protons and neutrons, which in turn are made up of quarks. This is true of bone, hair, the blood running through our veins, the veins themselves, the skin that contains everything that makes us a living organism; it’s true of the sidewalk we walk on, the footwear we walk in, the air we breath, and the lungs that turn that air into the exact mixture of oxygen needed to live. And so on.
There are no anti-protons or anti-neutrons, made up from anti-quarks, except for a few that physicists produce on purpose in large particle accelerators. In his seminal work A Brief History of Time, Stephen Hawking says we have evidence from cosmic rays that the same is true for all the matter in our galaxy; there are no anti-protons or anti-neutrons apart from a small number that are produced as particle/anti-particle pairs in high-energy collisions. If there were large regions of anti-matter in our galaxy, we would expect to observe large quantities of radiation from the borders between the regions of matter and anti-matter, where many particles would be colliding with their anti-particles, annihilating each other and giving off high-energy radiation.
As much as this is difficult to comprehend, it is important to note the fantastic picture it paints of intelligent design. Why should there be so many more quarks than anti-quarks? Why are there not equal numbers of each? Hawking puts it this way: “It is certainly fortunate for us that the numbers are unequal because, if they had been the same, nearly all the quarks and anti-quarks would have annihilated each other in the early universe and left a universe filled with radiation but hardly any matter.” (pg. 76) The result would have been no galaxies, stars or planets on which human life could have developed. I must mention that early in his career Hawking left the door open for the possibility of the existence of God. However, in an interview with Spain’s El Mundo in 2014, Hawking said, “Before we understood science, it [was] natural to believe that God created the universe. But now science offers a more convincing explanation.”
So What about these stringy thingys?
Theories of supergravity have developed from attempts to construct a unified field that describes all of the four basic forces. One of the essential features of quantum field theory is its prediction of “force-carrier” particles that are exchanged between interacting particles of matter. General relativity, which relates gravitational force to the curvature of space-time, provides a respectable theory of gravity on a larger scale. Supergravity theories permit extra dimensions in space-time, beyond the familiar three dimensions. Whoa! In essence, string theory states that there is a dimension beyond that of quarks. A quark is a subatomic or fundamental particle which possesses both an electric charge and a “strong” charge. They combine in groups of two or three to form composite objects held together by the strong force. Protons and neutrons are familiar examples of such composite objects – both are made up of three quarks.
According to Hawking, “Up to about twenty years ago, it was thought that protons and neutrons were ‘elementary’ particles, but experiments in which protons were collided with other protons or electrons at high speeds indicated that they were in fact made up of smaller particles.” (pg. 65) Quantum mechanics tells us that all particles are in fact waves, and that the higher the energy of a particle, the smaller the wavelength of the corresponding wave.
These “strings” vibrate in different patterns, thereby creating the different particles that make up the world around us. Literally, these vibrations define the very substance of the physical world. Everything is made up of tiny filaments of vibrating energy. Many physicists see string theory as the perfect solution for unifying the gravitational mechanics of astronomy with the quantum mechanics of electrons and other subatomic particles – one of the great unsolved problems in physics – because their differing mathematics resolve into one. The implication from string theory is that the underlying unity of matter is energetic “vibration.” At the root of all things is oscillation. The difference between the subatomic particles – between quarks, electrons, and neutrinos, for example – is simply the frequency at which they vibrate. Protons and neutrons in an atomic nucleus are simply composites of those subatomic particles.
The Many Dimensions of the Physical Realm
The physical realm has more dimensions than what we can see. Dimensions which are based upon finely-tuned mathematics. Equations so intricate that if off by even the slightest variation the universe would cease to exist. These “extra” dimensions have a very rich, interdependent geometry. One way in which science has been able to prove the existence of these extra dimensions is by aiming particles at each other in the Large Hadron Collider. The particles are sent round and round in a circle, near the speed of light. If the collision produces enough energy, then it may eject some of the debris from the impact, forcing it to enter into the other dimensions. This could be proven because the amount of energy present after the collision would be less than before, indicating it had drifted away. Energy cannot be created or destroyed, so it had to have gone somewhere.
The Voice of God: “Good Vibrations”
Just as different tones come out of different lengths of a string being plucked on a guitar, so different properties come from the different frequencies or tones of vibration characterizing certain subatomic particles. Even our thoughts are characterized by brainwaves of characteristic amplitude, frequency, and wavelength. Thought produces energy in our brain from the electrochemical activity between neurons. As the neural networks fire in a synchronous pattern with each other, this energy can actually be observed using an EEG.
Here’s the fascinating part. The Bible tells us God’s words are the very energy behind creation. God spoke and the entire universe and all its inhabitants came into existence. God’s thoughts were transmitted as spoken sound waves, thereby creating a physical universe which, at its most fundamental level, is governed by vibratory waves of little loops of string. If vibrations are the foundation of physical reality – remember, of course, that atomic particles are in constant motion – then it’s clear that spiritual truth transcends physical truth. Why are atoms and molecules so stable and yet so full of energy and motion? Scripture says, “For in [Christ] all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things have been created through Him and for Him. He is before all things, and in Him all things hold together.” (Colossians 1:16-17, NIV) [Emphasis mine.] In this manner, Scripture illuminates science. Science does not explain Scripture.
Concluding Remarks
Hawking, in his conclusion to A Brief History of Time, said, “We find ourselves in a bewildering world. We want to make sense of what we see around us and to ask, ‘What is the nature of the universe? What is our place in it and where did it and we come from? Why is it the way it is?” To try to answer these questions, we adopt a particular “worldview.” Everyone has one. Just as an infinite tower of tortoises supporting the archaic idea of a flat earth is such a picture, so is the theory of superstrings. Both are theories of the universe, though string theory at least is much more mathematically practical than the turtle idea. Einstein once asked the question, “How much choice did God have in constructing the universe?” According to Hawking, if no boundary proposal is correct, God had no freedom at all to choose initial conditions. He would, of course, still have had the freedom to choose the laws that the universe obeyed. Hawking believes this may not really have been all that much of a choice; there may well be only one, or a small number, of complete unified theories. Hawking states, “Even if there is only one possible unified theory, it is just a set of rules and equations.”
Let’s remember, however, that the very physics and mathematics by which Hawking and others attempt to explain the universe, including its beginning, did not exist at the time of the so-called Big Bang. Fascinating, no? I like this quote from NASA Science Beta Magazine Online: “According to the theories of physics, if we were to look at the universe one second after the Big Bang, what we would see is a 10-billion degree sea of neutrons, protons, electrons, anti-electrons (positrons), photons, and neutrinos. Then, as time went on, we’d see the universe cool. It would eventually reach the temperature where electrons combined with nuclei to form neutral atoms. Before this ‘recombination’ occurred, the universe would have been opaque because the free electrons would have caused light (photons) to scatter the way sunlight scatters from the water droplets in clouds.” I believe Genesis has a word or two about what caused light to appear.
Pope Pius XII made a very curious remark in 1951: “True science to an ever-increasing degree discovers God as though God were waiting behind each door opened by science.” More than a few scientists over the decades have said that the facts of the Big Bang, as they are slowly uncovered, could at the very least suggest the work of a Creator. In my opinion, science will never be able to take us to the exact moment of creation– only up to that point where philosophy, metaphysics, and theology begin. Before publicly concluding he was an atheist, Stephen Hawking initially made a tentative foray into this uncertain area by saying, “The odds against a universe like ours emerging out of something like the Big Bang are enormous. I think there are clearly religious implications whenever you start to discuss the origins of the universe. There must be religious overtones. But I think most scientists prefer to shy away from the religious side of it.”
“First this: God created the heavens and earth – all you see, all you don’t see. Earth was a sea of nothingness, a bottomless emptiness, an inky blackness. God’s Spirit brooded like a bird above the watery abyss. God spoke: ‘Light!’ and light appeared. God saw that light was good and separated light from dark. God named the light Day, He named the dark Night. It was evening, it was morning – Day One.”
(Genesis 1:1-5, MSG)
References
Boslough, J. (1985). Stephen Hawking’s Universe. New York, NY: Avon Books
Hawking, S. (1988). A Brief History of Time. New York, NY: Bantam Books
NASA Science (n.d.). “The Big Bang.” NASA Science Beta Magazine Online. Retrieved from: https://science.nasa.gov/astrophysics/focus-areas/what-powered-the-big-bang