Have you ever wondered why physics has to be so difficult?
“Why?” is always a dangerous question and the answer to this particular one depends on how deep you want to go into the subject. A good starting point may be: When physics is introduced in school, students learn about Newton’s mechanics, for example. This means that they come sideways into a subject that could track back to its roots at least 6000 years back. We talk 6000 years of accumulated (and often disposed of) knowledge about nature. Each new explanation of a physical process is built and builds upon what is already known.
To be quite frank, what are the expectations here? We do not run before we walk after all. And talk about a challenge for the teachers!
Newton’s physics is not even amongst the most complex things teachers have to teach and students have to study. One of the typical examples for physics as a difficult and somewhat weird subject is the whole deal about particles and waves. Small particles such as electrons can be looked upon as either one or the other, depending on what we want to find out about.
That cannot be right, now, can it? Nature does not wait for us to see how we want to tackle something before she decides which rules are going to be true. Einstein, at any rate, did not think that was the case. The results from the experiments done on the subject drove him nearly crazy.
As mentioned before, we develop ways to describe nature which are meaningful to us. “Waves” and “particles” are concepts, crutches which are supposed to help us imagine something which cannot be imagined. It is decidedly not surprising that our images and allegories do not fit nature exactly.
How do we learn anything then?
One of the professors who often visits my workplace at Andøya Space Center once told his students that “you have to just turn around and do something else sometimes, take a cup of coffee, for example, perhaps talk about the weather or something else for a while before you even begin to understand about particles and waves.”
The professor continued by pointing out that it could be a good idea to get a good night’s sleep before turning to the subject once more. In addition, it could be advantageous to find as many different sources on the subject as possible – not because any of them finally explained everything in simple terms. No, to be exposed to many different points of view would accelerate the process towards finding our own way to approach the problem.
In other words: We are supposed to think about the whole thing, think about something else and then think about the whole thing again. And again. Approach the subject from a different angle. Take a break, sleep, meet friends, do whatever else in order to then come back to the physics time after time from all possible vantage points until we get a grip of it.
This is not a revolutionary idea. It is like the rest of life, really. In football, for example, the process can be summarised in two sentences: “Go to practice.” “Leave practice”. But this is important. It is as true in sports as it in school. You have to be enormously talented and be born with the right mindset to truly learn about the physical principles and master all the mathematics on the last day before the exam in order to pass it or do well. And one can ask the question of how you got to be good enough at mathematics without practice.
Physics as a subject also makes it rather easy to construct excuses. You ask whether electrons are particles or waves, get an answer from the curriculum, get confused by the answer and conclude that physics is too strange to deal with. This is a powerful line of thought because physics is strange in many ways. How so? I do not have a definite answer but sometimes I feel like it has something to do with humans wanting to categorize absolutely everything. Electrons simply have to be particles or waves.
If you had asked the professor he would have told you that learning about nature is something different entirely than to know what things are called. We are not talking “being interested in science”. We are talking a profound wish to obtain knowledge which leads to what is called scientific literacy. Categorization is, in this regard, only a tool, nothing more. At very least we should not make a fuss about not being able to categorize something. Electrons are electrons, period.
Take enough coffee breaks and you will know what I mean.
Now read this: Two sides of reality
 “Complex topics, finally explained in a simple way!” I get a shiver running down my spine when I read something like this. Physics is tough. Mathematics, too. Think about it this way: It takes an effort to get up a mountain. Not everybody wants to do it either. There are paths which are easier than others, that is true. But at the end of the day you will have to get all the way up anyway, since the mountain is simply there. That is how it is. Period. It will take something to walk or climb to the top. Why do some people even like to embark on such a tough hike? Well, once you are up there…
 Take planets. What is a planet? Ask poor Pluto.