String Theory Towards An Answer To Everything: A Review Of “The God Equation”

Rahim Salhi

Some concepts are simply difficult to comprehend, even with a smartphone and Google at my disposal. Consider the unlikely notion that energy is emitted in quanta, or discrete packets, rather than continually flowing. Or the depressing hypothesis that the universe as a whole, which spans 93 billion light-years, may only be one of many parallel worlds. Throughout his final years, Einstein searched for a "theory of everything" that would link his theories of general relativity with quantum mechanics. Within the confines of what I know and read about physics today, these two hypotheses are not entirely consistent. As physicists have continued where Einstein left off, one solution is the string theory. By supposing that there are more worlds and dimensions in addition to the ones we are aware of, string theory merges the two theories.

String theory has existed for almost 50 years. It has long been considered the front-runner in the contest to reconcile the two physics paradigms, general relativity, and quantum theory. The rationale for this requirement is that each one accomplishes what it's meant to do in terms of forecasts. The theory of general relativity describes phenomena on a bigger, cosmic scale. It anticipates phenomena like thick, hefty objects distorting space-time. Quantum theory operates on the subatomic scale and predicts that if you run against various brick walls enough times, your atoms will eventually pass straight through the solid wall. The difficulty is that one hypothesis fails where the other begins.

Michio Kaku is a useful source to understand string theory. The theoretical physicist has established a successful second career as a science communicator, simplifying for the general public some of physics' most complex and esoteric ideas. His most recent best-selling book, The God Equation, details the lengthy effort to develop a "theory of everything," which would integrate quantum theory with Einstein's general theory of relativity and maybe lead to new insights into space and time. The strongest possibility for such an equation, in Kaku's opinion, is the string field theory, which he also co-founded.

In The God Equation, Michio Kaku outlines the topography of our current understanding of the cosmos and makes suggestions for how fresh perspectives could further our understanding. Kaku introduces the topic by describing the advances in physics that made it possible to understand the electromagnetic, gravitational, strong nuclear, and weak nuclear forces—the four fundamental forces that govern the universe. Kaku admits that “Although the quest for a unified theory was ignored by most physicists,” [2] Scientists every now and then are attempting to integrate these forces into a single theory in order to fully understand how nature operates at all scales. This one theory would be tremendously powerful if it could explain the underlying nature of the universe and the laws that govern it. Wormholes, time travel, and other concepts that up until now seemed to belong in science fiction.

Kaku provides a concise summary of how physics has changed over time and up to the present. He places special emphasis on the important scientific discoveries that transformed civilization and influenced the modern world. Kaku lays up the contemporary hunt for the so-called "God equation," a governing equation that unites all of the concepts articulated by these four forces, by summarizing the significant advancements in our understanding of the natural universe. This search is sometimes referred to as the "missing piece" in our comprehension of the basic forces.

String theory posits a basic structure to space. It follows that every item in the universe is made up of vibrating strings of energy. The theory avoids gravitational disaster by adding a limited, lowest size to the cosmos, but the unit threads are far smaller than the spatial structures. According to string theory, basic particles appear as undulating strings and membranes at nature's maximum zoom level, indicating dimensionality when seen up close. As Kaku adds in his book stating that strings: “with infinitely many particle types and with fields taking values not on points, but on loops and curves.” [2] The theory states that additional dimensions might potentially manifest in the structure of space. The range of particles that make up the visible universe is created by the many vibrational modes of the strings in this higher-dimensional realm.

However, skeptics point out that string theory has yet to make any experimental predictions. Dr. Chris Search goes even further: “Does string theory still exist?” This was a question he asked during his opening remarks in my class (Seminar in Science Writing) as he was invited by Dr. John Horgan to give a talk about his journey and views as a physicist at Stevens Institute of technology. Dr. Search asserts that “It was not created using the scientific method or deductive logic.” Instead, it is built on adductive reasoning, which proposes an explanation based on a known conclusion.

Since string theory does not provide a precise method of calculating the string vacua that give birth to the fundamental constants, it is also impossible to determine what values the fundamental constants should have. These include the gravitational constant G, Planck's constant h, the speed of light c, the masses of the basic particles, the angles at which quarks and neutrinos combine, the cosmological constant, and the coupling constants for the forces.[4] There are no hints provided by string theory for calculating these basic values. George Ellis and Joe Silk went even further in their paper published in Nature: “And with its many variants, string theory is not even well defined: in our view, it is a promissory note that there might be such a unified theory”.[5]

The history of science is rich with theories, some of which have been proven to properly represent reality over a certain range that we may explore it, and others of which have turned out not to explain reality but might have done so if nature had provided a different answer to our queries. Kaku is assisting the discipline of physics in making that connection by pushing the boundaries of understanding. His book is urging us to reconcile not only quantum physics and general relativity, but also notion and perception. The next great physics theory will almost certainly result in beautiful new mathematics and inconceivable new technology. The most it can accomplish, though, is to provide deeper meaning that ties back to us, the observers, who get to identify ourselves as the basic scale of the cosmos.

 

Since we still don't know how to connect the (macroscopic) theory of general relativity with the (microscopic) theory of quantum mechanics, we are at a crossroads in our knowledge of the physical universe. Whatever theories emerge, the vast scale is unavoidably significant since it is the world we inhabit and see. In essence, the answer is the universe as a whole, and the task for physicists as Dr. Search stated, “is to discover methods to make it appear in their equations.” Even if Kaku is correct, his string theory must average out to the smooth reality we see on a daily basis. Even if others are incorrect, there is an entire universe out there with unique qualities that must be explained - something that, for the time being, quantum physics alone cannot achieve.