Seriously, it is not that complicated

It was more than a 100 year ago that Max Planck introduced the notion of the quantization of radiation from a black body. The full-blown formulation of quantum mechanics is almost a hundred years old (the 5th Solvay conference more or less represents that achievement). Over the years since then, many ideas have been introduced about quantum physics in the struggle to understand it. Once new ideas have been introduced, nobody can ever remove them again regardless of how misleading they may be. Nevertheless, among these ideas, we can find enough information to form a picture representing an adequate understanding of quantum physics.

It would be very arrogant to claim that this understanding is unassailable or even complete. (I still have some issues with fermions.) Therefore, I simply call it my current understanding. It is a minimalist understanding in that it discards the unnecessary conceptual baggage (thus following Occam’s razor). Yet, it provides an ontology (although not one that guarantees everybody’s satisfaction).

I’ve written about many aspects of this understanding. So, where possible, I’ll thus link to those discussions. Where additional discussions may be necessary, I’ll postpone those discussions for later. Here then follows a breakdown of my current understanding of quantum physics.

Firstly, fundamental particles are not particles in the traditional sense. They are not “dimensionless points traveling on world lines.” Instead, they are better represented by wave functions or fields (or partites). Interactions among these fundamental fields (using the term “fields” instead of “particles” to avoid confusion) are dimensionless events in spacetime.

As a consequence, there is no particle-wave duality. Fields propagate as waves and produce the interference as, for example, seen in the double-slit experiment. Whenever these fundamental fields are observed as discrete entities, it is not a particle in the traditional sense that is being observed, but rather the localized interaction of the field with the device that is used for the observation.

Secondly, interactions are the key that leads to the quantum nature of the physical world. What Max Planck discovered was that interactions among fundamental fields are quantized. These fields exchange energy and momentum in quantized lumps. This concept was also reiterated in Einstein’s understanding of the photo-electric effect. Many of the idiosyncratic concepts of quantum physics follow as consequences of the principle of quantized interactions.

The Heisenberg Uncertainty Principle is not a fundamental principle. It is a consequence of the quantization relations associated with interactions. These relations convert conjugate variables into Fourier variables, which already represent the uncertainty principle. As a result, the conjugate variables inherit their uncertainty relationship from Fourier theory. It becomes more prevalent in quantum physics, due to the restrictions that the quantization of interactions imposes on the information that can be obtained from the observation of a single “particle.”

Planck’s constant only plays a physical role at interactions. Once these interactions are done, the presence of Planck’s constant the expressions of the fields have no significance. It can be removed through simple field redefinitions that have no effect on the physical representations of these fields. As a result, the significance that is attached to Planck’s constant in scenarios that are not related to interactions are generally misleading if not completely wrong.

Thirdly, another key concept is the principle of superposition. The interactions among fundamental fields are combined as a superposition of all possibilities. In other words, they are integrated over all points in spacetime and produce all possible allowed outcomes. As a consequence, after the interactions, the resulting fields can exist in a linear combination of correlated combinations. This situation leads to the concept of entanglement.

Since a single “particle” only allows a single observation, the different measurement results that can be obtained from the different elements in a superposition are associated with probabilities that must add up to one. The coefficients of the superposition therefore form a complex set of probability amplitudes. The conservation of probability therefore naturally leads to a unitary evolution of the state of the single particle in terms of such a superposition. This unitarity naturally generalizes to systems of multiple particles. It naturally leads to a kind of many-worlds interpretation.

It seems to me that all aspects of quantum physics (with the exception of fermions) follow from these three “principles.” At least, apart from the question of fermions, I am not aware of anything that is missing.

Inflated self-love

The media is full of it. Everywhere you see that people are told to love themselves; put themselves first; look out for “number one.” Such a notion is at the very least misleading, if not complete nonsense, and it is definitely dangerous.

A concern for oneself is built into our genes. Self-preservation has developed through biological evolution into a very strong instinct. Therefore, we don’t need to be told to love ourself. It comes naturally. But biological evolution is driven by the survival of the fittest. That makes for a very unfriendly world to live in.

Selfish child

The cultures of humanity oppose these strong instincts to allow the weak to survive as well, allowing the world to become a more friendly place to live in. Cultures accomplish it by instilling a concern for others.

The ancient biblical principles states “love your neighbour as much as you love yourself.” It represents a balance between the natural love all people have for themselves and the concern that should be extended to all other people they come in contact with.

This balance is important. It makes room for things like self-respect and self-confidence without which the balance would not be maintained. But it shows that such forms of self-concern should not exceed the level of concern for others.

A balanced level of competition with others is good and healthy, but when competition is driven too far it becomes destructive. In fact, it does not only harm others, but can start to be harmful to oneself.

So, don’t listen to all these calls for “learning to love yourself,” unless such messages are associated with self-development in balance with a healthy concern for others. A world full of selfish people is a very unfriendly world to live in, akin to the world in which the principles of the survival of the fittest rule, as they did during our biological evolution. In contrast, the foundation of a civilized world is the concern for others in balance with the concern for oneself.

Just delete “vacuum fluctuations”

How do you build a tower? One layer of bricks at a time. But before you lay down the next layer of bricks, you need to make sure the current layer of bricks has been laid down properly. Otherwise, the whole thing may be tumbling down.

The same is true in physics. Before, you base your ideas on previous ideas, you need to check that those previous ideas are correct. Otherwise, you would be misleading yourself and others, and the new theories may not be able to make successful predictions.

Physics is a science, which means that we should only trust previous ideas after they have been tested through comparison with physical observations. Unfortunately, there are some ideas that cannot be checked so easily. Obviously, one should then be very careful when you base new ideas on such unchecked ideas. Some people blame the current lack of progress in fundamental physics on this problem. They say we need to go back and check if we have not made a mistake somewhere. I think I know where this problem is.

Over the centuries of physics research, many tools have been developed to aid the formulation of theories. These tools include things like differential calculus in terms of which equations of motion can be formulated, and Hamiltonians and Lagrangians, to name a few.

Now, I see that some people claim that most of these tools won’t work for the formulation of a fundamental theory that includes gravity with quantum theory. It is stated that a minimum measurement uncertainty, imposed by the Planck scale, would render the formulation of equations of motion and Lagrangians at this scale impossible. Why is that? Well, it is claimed that the uncertainty at such small distance scales is large enough to allow tiny black holes to pop in and out of existence, creating havoc with spacetime at such small scales. This argument is the reason why people consider the Planck scale as a fundamental scale beneath which our traditional notions of physics and spacetime break down.

But why does uncertainty lead to black holes popping in and out of existence? It comes from an unchecked idea based on the Heisenberg uncertainty principle, which claims that it allows particles to pop in and out of existence, and such particles can have larger energies when the time for their existence is short enough. This hypothetical process is generally referred to as “vacuum fluctuations.” However, there does not exist any conclusive experimental confirmation of the process of vacuum fluctuations. Therefore, any idea based on vacuum fluctuations is an idea based on an unchecked idea.

Previously, I have explained that the Heisenberg uncertainty principle is not a fundamental principle of quantum physics, but instead comes from Fourier theory. As such the uncertainty principle represents a prohibition and not a license. It imposes restrictions on what can exist. Instead, people somehow decided that it allows things to exist in violation of other principles such as energy conservation. This is an erroneous notions with no experimental confirmation.

Hence, the vacuum does not fluctuate! There are no particles popping in and out of existence in the vacuum. There is nothing in our understanding of the physical world that has been experimentally confirmed which needs the concept of vacuum fluctuations.

Now, if we get rid of this notion of vacuum fluctuations, several issues in fundamental physics will simply disappear. For example, the black hole information paradox. A key ingredient of this paradox is the idea that black holes will evaporate due to Hawking radiation. The notion of Hawking radiation is another unchecked idea, which is based on …? You guessed it: vacuum fluctuations! So if we just get rid of this silly notion of vacuum fluctuations, the black hole information paradox will evaporate, instead of the black holes.

The beholder’s prerogative

Early this morning, I went outside onto my balcony to witness the sunrise. It made me feel good to experience something so beautiful.

Beautiful sunrise in Canada

So, I thought to myself, it must say something about the Creator who creates such beauty, even if it is just for a few fleeting moments. Then it also occurred to me that the Creator probably also instilled in me the ability to appreciate such beauty. It also includes the freedom to choose whether I would find it beautiful or not.

The deceptive lure of a final theory

There has been this nagging feeling that something is not quite right with the current flavor of fundamental physics theories. I’m not just talking about string theory. All the attempts that are currently being pursued share this salient property, which, until recently, I could not quite put my figure on. One thing that is quite obvious is that the level of mathematics that they entail are of a extremely sophisticated nature. That in itself is not quite where the problem lies, although it does have something to do with it.

Then, recently I looked at a 48 page write-up of somebody’s ideas concerning a fundamental theory to unify gravity and quantum physics. (It identifies the need for the “analytic continuation of spinors” and I thought it may be related to something that I’ve worked on recently.) It was while I read through the introductory parts of this manuscript that it struck me what the problem is.

If we take the standard model of particle physics as a case in point. It is a collection of theories (quantum chromodynamics or QCD, and the electro-weak theory) formulated in the language of quantum field theory. So, there is a separation between the formalism (quantum field theory) and the physics (QCD, etc.). The formalism was originally developed for quantum electro-dynamics. It contains some physics principles that have previous been established as scientific principles. In other words, those principles which are regarded as established scientific knowledge are built into the formalism. The speculative parts are all the models that can be modeled in terms of the formalism. They are not cast in stone, but the formalism is powerful enough to allow different models. Eventually some of these models passed various experimental tests and thus became established theories, which we now call the standard model.

What the formalism of quantum field theory does not allow is the incorporation of general relativity or some equivalent that would allow us to formulate models for quantum theories of gravity. So it is natural to think that what fundamental physicists should be spending their efforts on, would be an even more powerful formalism that would allow model building that addresses the question of gravity. However, when you take a critical look at the theoretical attempts that are currently being worked on, then we see that this is not the case. Instead, the models and the formalisms are the same thing. The established scientific knowledge and the speculative stuff are mixed together in highly complex mathematical theories. Does such an approach have any hope of success?

Why do people do that? I think it is because they are aiming high. They have the hope that what they come up with will be the last word in fundamental physics. It is the ambitious dream of a final theory. They don’t want to be bothering with models that are built on some general formalism in terms of which one can formulate various different models, and which may eventually be referred to as “the standard model.” That is just too modest.

Another reason is the view that seems to exist among those working on fundamental physics that nature dictates the mathematics that needs to be used to model it. In other words, they seem to think that the correct theory can only have one possible mathematical formalism. If that were true the chances that we have already invented that formalism or that we may by chance select the correct approach is extremely small.

But can it work? I don’t think there is any reasonable chance that some random venture into theory space could miraculously turn out to be the right guess. Theory space is just too big. In the manuscript I read, one can see that the author makes various ad hoc decisions in terms of the mathematical modeling. Some of these guesses seem to produce familiar aspects that resemble something about the physical world as we understand it, which them gives some indication that it is the “right path” to follow. However, mathematics is an extremely versatile and diverse language. One can easily be mislead by something that looked like the “right path” at some point. String theory is an excellent example in this regard.

So what would be a better approach? We need a powerful formalism in terms of which we can formulate various different quantum theories that incorporate gravity. The formalism can have, incorporate into it, as much of the established scientific principles as possible. That will make it easier to present models that already satisfy those principles. The speculations are then left for the modeling part.

The benefit of such an approach is that it unifies the different attempts in that such a common formalism makes it easier to use ideas from other attempts that seemed to have worked. In this way, the community of fundamental physics can work together to make progress. Hopefully the theories thus formulated will be able to make predictions that can be tested with physical experiments or perhaps astronomical observations that would allow such theories to become scientific theories. Chances are that a successful theory that incorporates gravity and at the same time covers all of particle physics as we understand it today will still not be the “final theory.” It may still be just a “standard model.” But it will represent progress in understanding which is more than what we can say for what is currently going on in fundamental physics.