Transcending the impasse, part VII

Vanity in physics

In this penultimate posting in the series on transcending the impasse in fundamental physics, I’ll address an issue that I consider to be one of the major reasons for the impasse, if the main reason. It is a topic that I feel very passionate about and one that I’ve written about in my book. It is a very broad topic with various aspects that can be addressed. So, I can see this topic becoming a spin-off series on its own.

Stating it briefly, without ranting too much, one can bring this issue into the context of the scientific method itself. As remarkable as the scientific method is with all the successes associated with it, if the very foundation on which it is based starts to erode, the whole edifice in all its glory will come tumbling down.

Now what is this foundation of the scientific method that could be eroded away? Well, the scientific method shares the property with capitalism and democracy in that it is a self-regulating feedback system. Each of these mechanisms is based on a property, a driving force, found in human nature that makes it work. For democracy, it is the reaction to the conditions one finds oneself in as provided by the authorities. For capitalism, it is basically greed and the need for material possessions. For the scientific method it is curiosity and need for knowledge and understanding.

So, the basic assumption is that those that are involved in the scientific process, the scientists, are driven by their curiosity. It has to a large extent been the case for centuries, and we have the accumulated scientific knowledge obtain through this process thanks to this curiosity.

However, during the past century, things started to change. It some point, due to some key event or perhaps as a result of various minor events, the fundamental driving force for scientists started to change. Instead of being internally motivated by their curiosity, they became externally motivated by … vanity!

Today, one gets the impression that researchers are far more concerned about egos than the knowledge they create. To support this statement, I can provide numerous examples. But instead of doing that, I’ll focus on only aspect: how this vanity issue impacts and causes the current impasse. Perhaps I’ll provide and discuss those examples in followup posts.

In the aftermath of the disappointing lack of results from the Large Hadron Collider (LHC), some people blamed other prominent researchers for their ludicrously exotic proposals and predictions. None of which survived the observations of the LHC.

Why would highly respected physicists make such ludicrous predictions? The way I see it, is as a gamble with high stakes. Chances were that these predictions would not have panned out. But if one of them did receive confirmation from the LHC, the return on investment would have been extremely high. The person that made the prediction would have become extremely famous not only among physicists, but probably also among the general public. It would probably have ensured that the person receives a Nobel prize. Hence, all the needs for vanity would have been satisfied instantly.

What about knowledge? Surely, if the prediction turned out to be correct, then it must imply a significant increase in our knowledge. True, but now one should look at the reality. None of these exotic predictions succeeded. This situation is not really surprising, probably not even to the people that made these predictions, because they probably knew the probability for their success to be extremely low. In that context, the motivation for making the predictions was never about the increase in knowledge. It was purely aimed at vanity.

An extreme example is this one physicists, who shall remain unnamed. He is known for making random predictions at a remarkable rate. It is obvious to everybody that he is not making these predictions because he expects them to work out. It is simply an attempt to be the first to have made a specific prediction in the off-chance that one of them came true. Then he’ll probably hope to receive all the vanity rewards that he so desperately craves.

It might have been amusing, were it not for the fact that this deplorable situation is adversely affecting progress in physics, and probably in science in general, albeit I don’t have such extensive experience in other fields of science. The observable effect in fundamental physics is a significant slowdown in progress that is stretching over several decades.

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Transcending the impasse, part V

Beauty as a guiding principle

Proceeding with the series on Transcending the impasse in fundamental physics, I like to address some of the issues that has been proposed as reasons for the current impasse. One such issue is the methods by which theorists come up with their theories in fundamental physics. Sabine Hossenfelder, for example, feels strongly that one should not use beauty in the mathematics as a guide to what could be a potential theoretical explanation for fundamental phenomena.

What am I talking about? Perhaps the idea that beauty can have anything to do with fundamental physics sounds ridiculous anyway. Well, beauty, as they say lies in the eyes of the beholder. To a theoretical physicist, the notion of beauty may refer to a different experience than to an artist or a lover. Potential salient aspects of the concept of beauty that would be relevant for all those that experience beauty may include things like symmetry, balance, consistency, etc.

However, it is not my intention here to philosophize about beauty and what it is. The fact of the matter is that physicist do sometimes use their notion of beauty to guide them in how they construct their theories, or in what they consider to be the correct theory. One example that springs to mind is the relativistic equation of the electron of Paul Dirac. It is said that Dirac was guided in its derivation by the beauty in the mathematics.

Paul Dirac, who apparently used beauty as a guide to derive the relativistic electron equation

The issue of whether one should use beauty, or for that matter anything else, as a guide in the construction of fundamental theories reveals a deeper issue at stake here. First, we need to identify a difference between fundamental theoretical physics and other fields of physics. I hasten to add that this is not to be interpreted as a distinction between what is inferior and what is superior.

Other fields of physics usually have some underlying scientifically established physical theory in terms of which investigations are (or can be) done. For example, in classical optics, the fundamental theory is electromagnetism. If all else fails, one can always start with electromagnetism and derive the theoretical description of a phenomena rigorously from Maxwell’s equations for electromagnetism. If the phenomenon includes quantum effects, one may need to fall back on quantum electrodynamics (QED) for this purpose.

In fundamental physics, one does not have this commodity. In most cases one can be lucky to have some experimental results to work with. Sometimes, the only guide is a nagging feeling that the current theories are not adequate. This is the case with quantum gravity. There are some conceptual arguments why general relativity cannot explain everything, but there are no experimental observations showing that something is missing.

How does one approach such a problem? One needs some form of inspiration. Different people tend to use different forms of inspiration. Some use the beauty in mathematics as their inspiration. Perhaps too many theorists have done that and ended up with unsuccessful theories. Hence, the reaction against it.

The point is, we need to remember what it takes to arrive at a scientifically established physical theory. Regardless of what method or form of inspiration or guiding principle one uses, the resulting theory can only become a scientific theory once it has survived experimental testing. In other words, the theory must be able to make predictions that can then be compared with actually observations and then be shown to agree with such observations.

So, in the end, whatever method theorists use to produce their theories is of no consequence, as long as it can succeed as a scientific theory. To put restrictions on the guiding principles, be it beauty or whatever else, makes no sense. Instead, one should allow the diversity of perspectives and freedom in thought to come up with potential theoretical explanations, and leave it to the rigors of the scientific method to sort out the successful theoretical descriptions from those that are to be discarded.

I do not believe that the use of beauty as a guiding principle is responsible for the current impasse in fundamental physics. That dubious honor belongs to a much more inimical phenomenon. But that is a topic for another day.

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Transcending the impasse, part III

Many-worlds interpretation

In my series on the impasse in physics and how to transcend it, I previously discussed the issue of classical vs quantum physics. Here, I want to talk about the interpretations of quantum mechanics.

There is much activity and debate on these interpretations. Part of it is related to the measurement problem. Is there such a thing as quantum collapse? How does it work?

David Mermin once said in an article in Physics Today that new interpretations are added every year and none has ever been ruled out. If this is true, then it indicates that the interpretations of quantum mechanics is not part of science, and therefore also not part of physics.

I am not going to say one should not work on such interpretations and try to make sense of what is going on, but the scientific method does not seem to help us here. Perhaps people will eventually come up with experiments to determine how nature works. I’ve seen some proposals, but they are usually associated with some new mechanisms, which in my view are unlikely to be correct.

It occurs to me that while we cannot say which of the interpretations are correct, we may just as well just pick one and work with that. So I pick the simplest one and when I want to figure out how things will work out in one of these experiments, then I can just consider how things will work according to this interpretation. If such a prediction turns out to be wrong, it would show that this interpretation (and all those that made the same prediction) is wrong after all.

The simplest interpretation according to me is the many-world interpretation. It is simple because it does not require the weird unexplained notion of quantum collapse. People don’t like it, because it seems to require such a lot of different worlds. For that reason it is also associated with the idea of a multiverse.

Hugh Everett III, the person that invented the many-worlds interpretation

Well no, those ideas are anyway misleading. In quantum mechanics, all interactions are described by unitary evolution. The picture that it represents is that there is a set of states that the universe can take on. One can think of each such state as a different description of the world. Hence “many worlds.” However, the actual state of the universe is a quantum superposition of all the possible worlds. In the superposition each world is associated with a complex probability amplitude. It means that some worlds are more likely than others. During interactions these probability amplitudes change.

That is the whole idea of unitary evolution. All the possibilities are already present right from the start. The only thing that interactions do is to change the probability amplitudes that are associated with the different worlds. During the evolution in time the different worlds in the superposition can experience constructive or destructive interference, which would change their probability amplitudes, making some less or more likely that they were before.

The number of worlds (number of terms in the superposition) stays the same. They don’t increase as a result of interactions. How many such worlds are there? Well, if we look at the properties of the set of such basis states, then it is often assumed to be a countable infinite number. However, it may turn out to be uncountably infinite, having what is called the cardinality of the continuum.

What is more is that these different worlds are not distinct unique worlds. One can redefine the basis set of worlds by forming different superpositions of the worlds in the original set to get a new set in which the worlds now look different.

How does all this relate to what we see? The dynamics of the universe causes the interferences due to the unitary evolution to favor a small set of worlds that look very similar. This coherence in what the world looks like is a result of the constructive interference produced by the dynamics.

So the world that we see at a macroscopic level is not just one of these worlds. It is, in a sense, a conglomeration of all those worlds with large probability amplitudes. However, the differences among all these worlds are so small that we cannot notice it at a macroscopic level.

OK, not everything I said here can be confirmed in a scientific way. I cannot even proof that the many-worlds interpretation is correct. However, by thinking of it in this way, one can at least get some idea of it that makes sense.

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Transcending the impasse, part I

The current impasse in fundamental physics stifles progress. The rate of advances in our understand has slowed down. Although several exotic predictions have been made in recent years, none of these seem to be correct. Have we reached the end of our ability to learn more about the universe we live in?

It has been suggested that the way forward is to go back and fix what is wrong. Is there then something wrong with what we’ve learned before? Apparently yes. We are biased by what we think we know. It misleads us to conjure up theories that cannot work.

How is this possible? Would such misconceptions not have been ruled out by experimental observation? That’s the problem. Much of what we think we know never got tested by experimental observations.

As an example, one is reminded of all the aspects of quantum physics that is not currently understood. Yes, we know enough about quantum mechanics (the mathematical formalism) to do calculations. The problem is that we then go and interpret what we see. That part cannot be tested by experiments.

For example, in certain interpretations of quantum mechanics it is believed that the wave function collapses to produce (or because of) the result we observed. Nobody really knows how this works. This is the measurement problem, which is currently a hot topic in quantum foundations.

But is this even science? How is this going to help us move forward? It occurs to me that these types of problems require us to step out of this struggle and get some distance from it. I said elsewhere that wisdom is the path to knowledge. Perhaps we need to get the metaphysics right before we will be able to get the physics right. We need to separate that which we can learn from a scientific approach from that which cannot be investigated scientifically.

Perhaps there is not such a clear cut distinction between those aspects of quantum physics that can and cannot be studied scientifically. However, it is not difficult to see where we are bound to waste much time with potentially limited or no advances.

In the following posts, I intend to address some specific aspects of the current impasse and how it impacts our current understanding. Although I’m not a fan of philosophy, some of these discussions may touch on some philosophical aspects of the topic – the metaphysics – in as far as it may show us the way.

Wisdom is the path to knowledge

As a physicist, I cherish the freedom that comes with the endeavor to uncover new knowledge about our physical world. However, it irks me when people include things in physics that do not qualify.

Physics is a science. As a science, it follows the scientific method. What this means is that, while one can use any conceivable method to come up with ideas for explaining the physical world, only those ideas that work survive to become scientific knowledge. How do we know that it works? We go and look! That means we make observations and perform experiments.

That is the scientific method. It has been like that for more than a few centuries. And it is still the way it is today. All this talk about compromising on the basics of the scientific method is annoying. If we start to compromise, then eventually we’ll end up compromising on our understanding of the physical world. The scientific method works the way it works because that is the only way we can know that our ideas work.

Some people want to go further and put restrictions on how one should come up with these ideas or what kind of ideas should be allowed to have any potential to become scientific knowledge even before it has been tested. There is the idea of falsifiability, as proposed by Karl Popper. It may be a useful idea, but sometimes it is difficult to say in advance whether an idea would be falsifiable. So, I don’t think one should be too exclusive. However, sometimes it is quite obvious that an idea can never be tested.

For example, the interior of a black hole cannot be observed in a way that will give us scientific knowledge about what is going on inside a black hole. Nobody that has entered a black hole can come back with the experimental or observational evidence to tell us that the theory works. So, any theory about the inside of a black hole can never constitute scientific knowledge.

Now there is this issue of the interpretations of quantum mechanics. In a broader sense, it is included under the current studies of the foundations of quantum mechanics. A particular problem that is much talked about within this field, is the so-called measurement problem. The question is: are these scientific topics? Will it ever be possible to test interpretations of quantum mechanics experimentally? Will we be able to study the foundations of quantum mechanics experimentally? Some aspects of it perhaps? What about the measurement problem? Are these topics to be included in physics, or is it perhaps better to just include them under philosophy?

Does philosophy ever lead to knowledge? No, probably not. However, it helps one to find the path to knowledge. If philosophy is considered to embody wisdom (it is the love of wisdom after all), then wisdom must be the path to knowledge. Part of this wisdom is also to know which paths do not lead to knowledge.

It then follows that one should probably not even include the studies of foundations of quantum mechanics under philosophy, because it is not about discovering which paths will lead to knowledge. It tries to achieve knowledge itself, even if it does not always follow the scientific method. Well, we argued that such an approach cannot lead to scientific knowledge. I guess a philosophical viewpoint would then tell us that this is not the path to knowledge after all.

Diversity of ideas

The prevailing “crisis in physics” has lead some people to suggest that physicists should only follow a specific path in their research. It creates the impression that one person is trying to tell the entire physics community what they are allowed to do and what not. Speculative ideas are not to be encouraged. The entire physics research methodology need to be reviewed.

Unfortunately, it does not work like that. One of the key underlying principles of the scientific method is the freedom that all people involved in it have to do whatever they like. It is the agreement between these ideas and what nature says that determines which ideas work and which do not. How one comes up with the ideas should not be restricted in any way.

This freedom is important, because nature is resourceful. From the history of science we learn that the ways people got those ideas that turned out to be right differ in all sorts of ways. If one starts to restrict the way these ideas are generated, one may end up empty handed.

Due to this diversity in the ways nature works, we need a diversity in perspectives to find the solutions. It is like a search algorithm in a vast energy landscape. One needs numerous diverse starting points to have any hope to find the global minimum.

Having said that, one does find that there are some guiding principles that have proven useful in selecting among various ideas. One is Occam’s razor. It suggests that one starts with the simplest explanation first. Nature seems to be minimalist. If we are trying to find an underlying system to explain a certain phenomenology, then the underlying system needs to be rich enough to be able to produce the level of complexity that one observes in the phenomenology. However, it should not be too rich, leading to too much complexity. As an example, conjuring up extra dimensions to explain what we see, we produce too much complexity. Therefore, chances are that we don’t need this.

Another principle, which is perhaps less well-known is the minimum disturbance principle. It suggests that when we find that something is wrong with our current understanding, it does not make sense to through everything away and build up the whole understanding from scratch. Just fix that which is wrong.

Now, there are examples in the history of science where the entire edifice of existing theory in a particular field is changed to solve a problem. However, this only happens when the observations that contradict the current theory start to accumulate. In other words, when there is a crisis.

Do we have such a kind of crisis at the moment? I don’t think so. The problem is not that the existing standard model of particle physics have all these predictions that contradict observations. The problem is precisely the opposite. It is very good at making predictions that agree with what we can observe. We don’t seem to see anything that can tell us what to do next. So, the effort to see what we can improve may well be beyond our capability.

The current crisis in physics may be because we are nearing the end of observable advances in our fundamental understanding. We may come up with new ideas, but we may be unable to get any more hints from experimental observation. In the end we not even be able to test these new ideas. This problem starts to enter the domain of what we see as the scientific method. Can we compromise it?

That is a topic for another day.

The thing about philosophy

As a physicist, one tends to have encounters from time to time with the world of philosophy. While some physicists would embrace it and acquaint themselves as much as possible with the various topics, I tend to regard it with a good measure of suspicion. The reason is that philosophy is not a science. It cannot (and should not) test the ideas to see if they are true. In those cases where these ideas (political philosophy) were tested, the results ended up being severely disastrous.

As a result of my suspicion, I deliberately kept myself ignorant of philosophy. But ignorance is never anything to brag about.  So, I decided to read up a little about it. I bought a book that summarizes the different philosophical ideas that was developed over the history of humanity. Although it does not give any detail understanding of any particular idea. It gives one a broad perspective of all the ideas and some idea of who said what.

One thing that becomes clear from such a broad perspective is how diverse these ideas are; how drastically these ideas can differ from each other. Despite the fact that none of these ideas can in any way be confirmed, their proponents are very strongly convinced of their veracity even in cases where they are completely ludicrous .

One of the sad things is the notion of a “proof” where someone tries to show that their ideas are irrefutable. Such proofs consist of supposedly logical arguments. But the steps in these arguments often incorporate hidden assumptions that have not and cannot be shown to be true. As a result these so-called proofs never survive for long. So much for being a proof.

There are situations where people’s ideas have been implemented, especially in the field of political philosophy. In those cases, these ideas had a huge impact on the history. Unfortunately, this impact is usually of a severely negative nature. The French revolution, Nazism and Communism, were all practical implementations of philosophical ideas and the associated atrocities provide clear evidence of just how dangerous it is to follow such ideas.

What is the conclusion then? If philosophy cannot provide the wisdom that it is supposed to provide, does it have any value? I do think it has some value, but one that is far humbler than its proponents would like to believe. Although it cannot provide any wisdom directly, it can provide us with a clearer understanding of the path to wisdom. In this case, I’m specifically thinking of its role in describing and maintaining the scientific method. Perhaps I’ll write more about that some other day.