What is Quantum Physics, Why Did It Come About, and What Impact Does It Have on Human Life?

William Thomson, better known in history as Lord Kelvin, declared the end of physics in the early months of the 20th century. He, who was the founder of the absolute zero-based global temperature system, confidently stated at that time: "There is no new subject left to discover in physics, and the only task ahead is to refine calculations." However, since Lord Kelvin's death in 1907, at least two major revolutions have occurred in the world of physics and our beliefs about the workings of the universe, and each time we have realized how little we know about the universe. First, Einstein upended the conventional models of Newtonian classical mechanics with his introduction of relativity, and then a group of prominent physicists collaboratively introduced quantum mechanics; a framework that changed our understanding of the universe and the methods of knowing it so profoundly that no one could boldly declare the end of physics like Lord Kelvin did. Today, discussions about quantum physics and even the quantum physics revolution are everywhere, from profound developments in particle physics to efforts to build quantum computers, to the extent that some scientists say this knowledge has the potential to expand our understanding of the universe and solve complex problems at lightning speed. On the other hand, this name has stepped outside the realm of science and is sometimes used by charlatans in phrases like quantum healing or quantum mysticism. But what is quantum physics in simple terms, and why did it come into existence? A conversation with Pedram Roshan, a member of the Google Quantum team, 1399. How does quantum processing transform pharmaceuticals? A brief history of quantum mechanics. In the same year that Lord Kelvin announced the end of physics, a scientist named Max Planck began working on his fundamental theory. Planck started this effort to explain some phenomena that classical physics could not address. Newtonian mechanics adequately explained most events in our surrounding world, but when it came to certain topics like black body radiation or the behavior of light, it lost its ability to respond. Planck's efforts began with a focus on solving a problem regarding the concept of black body radiation, which classical physics could not address. This issue can be simply stated as follows: according to classical physics theories, the radiation of a black body (a hypothetical body that can completely absorb and emit all electromagnetic rays) would increase indefinitely with increasing wave frequency and approaching ultraviolet waves. However, this explanation was neither possible nor consistent with experiments. To solve this problem, Planck proposed the assumption that energy does not have a continuous structure and is distributed in separate packets called quanta of energy. In 1905, when Einstein introduced the photoelectric effect, he stated that light could be considered as separate and discrete packets of energy called photons. Thus, the transformation of energy, instead of being a continuous process, takes a stair-step form, thereby providing confirmation for Planck's theory. The 1920s, however, was the time when quantum mechanics took shape and underwent significant development. Prominent physicists like Werner Heisenberg, Niels Bohr, Max Born, and Erwin Schrödinger advanced this theory. After these formulations, Heisenberg introduced the uncertainty principle; a principle stating that regardless of measurement accuracy, one can never predict two fundamental characteristics of a particle (such as position and momentum) with high precision, and the accuracy in measuring one means losing accuracy in measuring the other. In 1927, Heisenberg and Niels Bohr presented the Copenhagen interpretation of quantum structures, which is one of the most common interpretations of this theory among physicists. In the 1940s, this theory was developed into quantum field theory, from which a structure like the standard model of physics emerged to interpret the behavior of the universe at its most fundamental levels. What does all this mean? The summary of the story can perhaps be stated without scientific precision as follows: when we deal with the universe at conventional scales, such as when we want to calculate the motion of a satellite, the orbit of a planet, the movement of a billiard ball, the time required for a speeding car to stop, or electric currents in power transmission lines, we can use classical physics tools. However, if we turn to objects with high mass or those moving at speeds close to the speed of light, we need to use relativistic tools to explain their motion and behavior, and if we delve into the world of fundamental particles and their behaviors, we need to use mathematics and another explanation of the universe that quantum mechanics provides us. Using models based on relativity for the normative dimensions we have around us is possible but unnecessary, and the effect it has on the outcome is so negligible that it can be disregarded, allowing us to use classical mechanics laws instead. Quantum physics in the Nobel Prize 2023 in medicine, physics, and chemistry was awarded to whom and why? Does the emergence of quantum mechanics mean that the knowledge prior to it is meaningless? The short answer is no. Based on the observations we have from the universe and its behaviors, we formulate models to describe it. These models, after emerging from the crucible of experimentation, form the prevailing theory or paradigm until an issue arises that challenges that paradigm. In this case, efforts to explain a method for addressing that issue emerge, which can sometimes provide new paradigms for interpreting part or the entirety of the universe. Such a paradigm shift is referred to as a scientific revolution – according to the interpretation and expression of Thomas Kuhn. A scientific revolution, more than denying the past, stands on the shoulders of the past to gain a better interpretation of the universe. The descriptions that this model of the universe provides and the mechanisms it offers to scientists enable the emergence of new technologies like quantum computing. Therefore, can it be said that according to quantum physics, there is no certainty in the universe? No. This is a misunderstanding of Heisenberg's uncertainty principle. This principle, which caused many debates and discussions among scientists at the time it was introduced, including famous mind games and debates between Einstein and Heisenberg, concerns specific fundamental particles and discusses the impossibility of precisely determining two of their characteristic components at the subatomic scale. This principle does not mean that you cannot determine the coordinates or speed of a projectile like an airplane or a person, and it only applies in the scientific language related to quantum physics. Your results still depend on your actions, and you cannot blame quantum mechanics for not reaching your desired goal. When Einstein spoke at a scientific society in Pennsylvania on December 28, 1934. So what about things like quantum mysticism and quantum healing? In a word, using the term quantum in any context other than quantum mechanics, if not previously defined, is erroneous. For example, when referring to something called quantum mysticism, if the intention behind the word quantum refers to quantum physics, then you are dealing with pseudoscience and superstition and likely charlatanism. Similarly, if you encounter claims of using quantum energies to treat diseases like cancer or the common cold, you can be sure you are dealing with superstition. Adding the word quantum behind anything does not give it scientific weight, and this word only has meaning in its scientific context, which requires advanced mathematics for examination and use.