String Theory Explained – What is The True Nature of Reality?
What Is String Theory ?
In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. String theory describes how these strings propagate through space and interact with each other. On distance scales larger than the string scale, a string looks just like an ordinary particle, with its mass, charge, and other properties determined by the vibrational state of the string. In string theory, one of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity.
String theory is a broad and varied subject that attempts to address a number of deep questions of fundamental physics. String theory has contributed a number of advances to mathematical physics, which have been applied to a variety of problems in black hole physics, early universe cosmology, nuclear physics, and condensed matter physics, and it has stimulated a number of major developments in pure mathematics. Because string theory potentially provides a unified description of gravity and particle physics, it is a candidate for a theory of everything, a self-contained mathematical model that describes all fundamental forces and forms of matter. Despite much work on these problems, it is not known to what extent string theory describes the real world or how much freedom the theory allows in the choice of its details.
String theory was first studied in the late 1960s as a theory of the strong nuclear force, before being abandoned in favor of quantum chromodynamics. Subsequently, it was realized that the very properties that made string theory unsuitable as a theory of nuclear physics made it a promising candidate for a quantum theory of gravity. The earliest version of string theory, bosonic string theory, incorporated only the class of particles known as bosons. It later developed into superstring theory, which posits a connection called supersymmetry between bosons and the class of particles called fermions. Five consistent versions of superstring theory were developed before it was conjectured in the mid-1990s that they were all different limiting cases of a single theory in 11 dimensions known as M-theory. In late 1997, theorists discovered an important relationship called the AdS/CFT correspondence, which relates string theory to another type of physical theory called a quantum field theory.
One of the challenges of string theory is that the full theory does not have a satisfactory definition in all circumstances. Another issue is that the theory is thought to describe an enormous landscape of possible universes, which has complicated efforts to develop theories of particle physics based on string theory. These issues have led some in the community to criticize these approaches to physics, and to question the value of continued research on string theory unification.
String theory is definitely one of the most popular theories in Physics that are widely overused in pop culture today. I think everybody would agree that the most popular example of this is the CBS show The Big Bang Theory. It is impossible to miss hearing about it in a lot of episodes, since it’s what Sheldon Cooper, one of the main protagonists of the show, is dedicating all of his energy on. A lot of the popular names of scientific communicators nowadays definitely have talked about this at some point, like Neil de Grasse Tyson, Bill Nye, the two Brians, Brian C0x and Brian Greene. All of which are names that are looked up to in the scientific community. And we can’t blame him since this is really remarkably one of the most controversial and daring theories of physics in the current date. Are you not sold yet as to how extremely important this theory is? Okay, sure. Let me tell you a bit more. According to Dr. Michio Kaku, a well-known popularizer of science and highly revered theoretical physicist, string theory can answer a lot of questions about our very own universe: what events occurred at the edge of time and space, precisely “before” the Big Bang, what exactly can we expect inside a black hole, and even the possibility of travelling instantly in space up to parallel universes through what we call wormholes. I think you can imagine how much of the current trends of sci-fi proliferated because of these ideas existing. Honestly, if this doesn’t get you extremely excited about this topic, I don’t know what will. But assuming you already are interested, let’s take a deep dive on what exactly this theory is, shall we? Or at least let’s try to accomplish that, since even the scientists who study this theory are also still struggling to fully understand every aspect of it.. The story of string theory began when physicists desired for the most simplified explanation for everything in the universe. These scientists always have this thing of wanting to compress explanations into something as neat and as simple as possible. Specifically, they were aiming to find a single line of equation which can be used to describe every phenomena in the universe: how a bird flies in the sky, how planetary motion comes about, how electricity works… It would certainly be something astonishing if only we could describe this into one line of Math, doesn’t it? Back in the early days of modern physics, there were five fundamental forces of nature were known: electricity, caused by the motion of electrons; magnetism, which describes an innate physical phenomena of objects; the weak nuclear force, responsible for nuclear decay; the strong nuclear force, or the force holding together the nucleons in an atom, keeping them from breaking apart due to the repulsive force of the electrostatic force. The earliest success at unifying these forces was done by James Clerk Maxwell, when he laid down the equations that define the interrelationship between electricity and magnetism. According to his study, an electrical current can induce magnetism, and vice versa. The resulting theory was called electromagnetism. Fast forward to the early 20th century and the quest takes us to the two of the most well-known theories in physics nowadays: the theory of general relativity, which best describes the extremely large and massive; and quantum mechanics, describing the extremely light and small. Both of which had some, if not most involvement by physics superstar, Albert Einstein, by the way. Quantum mechanics reveals that every particle has a dual nature: everything has both a wave-like and a particle-like property. However, this is not completely pretty, as in this approach, the best we can come up with are probability expressions of particles. But it does accomplish the task of describing subatomic particles and how they interact with the highest accuracy, despite this incapacity. But before you label this theory as bananas, it is important to know that it is not entirely the scientists fault. What quantum mechanics also reveals is that when we try to observe particles in the quantum scale, this observation has a consequential effect. You might be thinking “how did we come to that? I thought we were doing so well?” Well, as finite beings, we are limited by our own means of observation. For us to actually observe something, we have to experience it. Usually, this experience entails seeing things and recording what we see. A pretty easy task, right? Well, at some point, it stops being as simple as that.