Critique of Lee Smolin’s Problems with Physics

Critique of Lee Smolin’s Problems with Physics

Lee Smolin, in his book, describes five different issues that he believes are problematic to theoretical physics. Among these is the problem of quantum gravity, where he claims that quantum theory should be combined with the theory of relativity to give a complete theory of nature that would eliminate the problem of infinities in existing theories. He also has a problem with quantum mechanics theory, which he claims does not make sense. He, therefore, claims that this problem could be solved by either making the existing theory to have sense or inventing a substitute theory that would make sense. The other problem is the unification of particles and forces. Due to the relationship between particles and forces, Lee claims that there should be a unified theory that could explain all the manifestations of a single entity. The problem of cosmological mysteries and the tuning problems are other problems that the author explains in his book. Although Lee’s view on theoretical physics is valid to some extent, he fails to consider some essential scientific aspects that ultimately make his argument not convincing.

Lee also suggests that the quantum theory and the general theory of relativity should be combined to produce a unified theory that can claim to be the complete theory of nature. He calls this problem the problem of quantum gravity. He claims that individually, the quantum and relativity theories have issues with infinities. He states that naturally, there has not yet been discovered anything measurable with an infinite value. However, in the quantum and relativity theories, physically sensible entities are predicted to have an infinite value. Due to the controversy of these theories with nature, Lee claims that nature is just trying to punish impudent theorists who want to break her unity. The author then goes on to explain how the individual theories have problems with infinities. As for the relativity theory, he suggests that the infinity problem is seen when the matter in a black hole has its density, and gravitational force quickly becomes infinity. He says that when this theory is trusted to describe the history of the universe, then there would be a point when the density of the world would become infinity, and the theory’s equation would be broken. He, therefore, views the relative theory as inadequate to explain some essential elements.

The quantum theory, on the other hand, also has some problems with infinities. Lee states that these problems appear when one wants to describe fields such as the electromagnetic fields using quantum mechanics. According to the quantum theory, electric and magnetic fields have values at any point in space (D’Ariano, Chiribella & Perinotti, 2017). This, according to Lee, means that there would be an infinite number of variables even in a finite volume of a substance. The author, therefore, claims that an unlimited number of variables that uncontrollably fluctuate could lead to equations that get out of hand and estimates of infinite figures when one asks about the probability of something happening. Lee argues that individuals cannot help this but accept the fact that an essential part of Physics is missing. He suggests that when gravity is taken into consideration when formulating new theories, all would be done. This is because gravity would take into account all the fluctuations and produce finite values. Thus, essentially, Lee argues that there is a need for a unified theory that would answer all questions in terms of sensibility and finite numbers.

However, Lee’s concern over infinity problems with quantum and infinity theories could be termed as unconvincing, or rather, he is ignorant of some scientific facts. World renown physicists such as Freeman Dyson and Phil Anderson agree to the fact that there is no quantum limit for gravity, but rather, the limit only exists for grossly macroscopic phenomena. Lee, in his argument, assumes that gravity may have a quantum limit, which is wrong. As he suggests that the inclusion of gravity in the new theory would eliminate infinite problems, he gets is wrong. Gravity has no quantum limit, and it would only lead to more infinity problems. Apart from making the false assumption, Lee’s argument in this problem is also aesthetic. He only views the two theories, the quantum, and general relativity theories, as problematic in explaining and relating different aspects. He advocates for a unified theory that could simplify things. Thus, although Lee’s argument on the problem of quantum gravity is valid to some extent, it can be dismissed due to ignorance of the fact that gravity has no quantum limit

One of Lee’s problems requires research to ascertain whether various particles and forces could be unified in a single theory that would explain all as expressions of one fundamental entity.  He calls this problem, ‘the unification of particles and forces.’  Lee’s argument starts with an explanation of how the attempts to unify magnetism, electricity, and gravity could be successful, were it not for quantum theory. He also illustrates how the description of the world has been made easier by the unification of all particles into two main categories; quarks and leptons. Quarks are the components of protons and neutrons and all particles that resemble them. Leptons, on the other hand, leptons are all particles that are not quarks. Lee says that these two types of particles, in combination with the four types of forces; magnetism, electricity, gravity, and nuclear forces, are all one needs to explain any known thing in the world. He, however, says that fundamental equations that result from relating the forces and particles have had the problem of repeatedly adjusting the numerous constants associated with the comparison. Lee thus suggests that there is a need to have a unified theory that could explain all the expressions of particles and forces in a single entity.

Therefore, in his third problem, Smolin thinks that is would be necessary when a unified field theory that could predict all the fundamental constants that are observed in nature. This issue is, however, no that problem but rather an aesthetic guess of how things should be. Lee does not argue from a physicist’s point of view. He only points out how cumbersome it is to master all existing constants to solve or describe a particular thing. Many people, however, agree with the idea that the universe needs to have a specific theory that can unify all particles and forces. Most of these people, as evidenced in Lee’s argument, base their point of view on history and aesthetic reasons. Typically, many physics would prefer to remember a few things rather than many things. Historically, when the magnetic, light, and electric forces were unified, many physicists found it as a pleasure since the no longer needed to memorize all the equations related to the three types of forces. Lee, in his argument, wants to emulate these people. He only wants a unified theory to be happy and reduce cumbersome work. The author’s argument in this problem is, therefore, not a significant concern since it is not on a scientific basis.

All in all, Smolin’s argument is acceptable in some way, although he ignores essential scientific facts in his reasoning. In his famous first problem with theoretical physics, Smolin suggests that there is a need to have a complete theory of nature that could eliminate the problem of infinities experienced in the quantum and the general relativity theories. He argues that in this ultimate theory, gravity should be included to eliminate the problem of infinities. In this argument, Smolin assumes that gravity has a quantum limit, which is wrong. Gravity has no quantum limit, and its inclusion into the ultimate theory of nature would only result in more infinity problems. In the problem of unification of forces with particles, Smolin wants one to ascertain whether the various particles and forces could be unified that could explain all the expression of a single entity. He thinks that the current theories have numerous constants, with each constant representing a particular characteristic. The problem here is that one has to use too many equations or theories to describe a particular phenomenon. This argument is, to some extent, invalid since it is rather aesthetically rather than scientifically based. Therefore apart from making wrong assumptions, Smolin sometimes argues from a non- scientific point of view, which makes his arguments less convincing.

References

D’Ariano, G. M., Chiribella, G., & Perinotti, P. (2017). Quantum theory from first principles: an informational approach. Cambridge University Press.