Conservation laws in physics
There's a chapter dedicated to conservation laws. What does it come to your mind when someone talks about "conservation"? Maybe it indicates that some value property can be foreseen based on another one? Basically, conservation says that you can measure an amount of something and then find this same value in another situation. Cool! Look how powerful it is! For example, electric charges are conserved. Electrical charges measure the interaction between an object and the electrical field. But who are those objects? We can add several levels to analyse how charges are conserved by describing those objects with more or less details. We can look at conservation as something like A =B. However, if A=(a+b+c) and B= (c+d+e), then we move towards complexity. And it’s when things leave the role of trivial and acquire complexity. So, back to electrical, charges, will we consider protons, neutrons and electrons only or will we consider other subatomic particles?
And it seems that as the times passes by and we discover more things, we become more creative and we find extra methods to describe our objects. So (a+b+c) may become, actually, equivalent to ((a1+a2+a3+a4) + b + c)… Wow! But… how do we get more creative? How do we notice that a is actually a composition of (a1+a2+a3+a4)? Research… Daydream… Explore…
What about the opposite case — we were expecting something to be conservative, we do experiments and boom! We get missing numbers. Is out theory invalid or did we forget to include something? Again, we need extra tries and creativity. That's actually that makes me love science so much — these 'AHA!' moments…
Feynman also gives an example of quasars — we do not know much about them, so maybe we make an assumption, break a conservation law and get sad. But again, we do not know too much about them, so there's also a chance that we are investigating over something we do not have enough information. And look! This recursive process — I do expect something, I find a diverging answer, I go back and try to find something entirely new — this also moves science forward! :)
[Things that I have learned reading this part of the book: leptons, strangeness, why do physicists measure energy by so many different ways?]
[Next post about Feynman's book — "Symmetry in physics"]