I used to occasionally write science posts with a philosophical flavour. Steemit might find some of them interesting. Below is a run-down of what I found to be a fascinating talk from Murray Gell-Mann about the relationship between elegance and correctness in physical theories.
Physicist Murray Gell-Mann argues why beautiful and elegant theories tend to be correct. (Spoiler: He argues that the correctness of elegant theories is due to nature's self-similarity. "Nature conforms to herself", and so exploring the symmetries and structure of a theory often indicates the correct description of phenomena outside the scope of the theory).
Highlights
3:15: He notes that a beautiful and elegant theory is more likely to be right than ones that aren't. "If you're looking for the right theory, look for the beautiful one". He goes on to talk about how the partial theory of the weak force he and others discovered did not agree with important experiments, but it was so beautiful, they published it anyway. Later, it was discovered that the experiments were wrong.
5:59 He raises the question of why beautiful theories are more likely to be right, and whether it is due to the way in which humans construct theories, or due to some deeper pattern of nature. He argues that the laws of physics are not just constructs of the human mind.
14:30 : The history of the universe is co-determined by three things.
(1) A fundamental quantum theory of particles and forces.
(2) An unimaginably long sequence of fundamentally random events.
(3) The initial conditions of the universe.
The press regularly talks about a theory of everything, but it would not be a theory of everything, as it would not determine the history of the universe. It can only assign probabilities to possible histories of the universe, given some initial conditions.
19:59: He proposes an explanation for why beauty and elegance is a successful criteria for guessing correct theories. As physicists go to shorter and shorter distances, they notice that the manifestations of the laws at different scales are approximately self-similar. "Nature Conformable to Herself". So the explanations of new phenomena naturally emerge from old theories.
Newton found that the gravitational force is proportional to 1/d2. The electrical force was found to obey the same law.
In physics, a system exhibits symmetry if there is an operation you can perform on the system that doesn't change it. The theory of electromagnetism is symmetrical under all rotations.
Einstein looked at the symmetries of electromagnetism, and applied them more broadly to mechanics. This is special relativity.
26:15: He shows a slide of maxwell's equations in their original form, in vector form, and in their relativistic form. By taking advantage of symmetries, equations can be expressed more elegantly.
28:40 Frank Yang and Robert Mills took advantage of even higher symmetries to generalise Maxwell's equation. They did not know what this generalisation implied, but it was a beautiful theory, whatever it was. It was later discovered that it was the theory of the strong nuclear interaction (chromodynamics). It is an example of a gauge theory. Gauge theories are theories where the symmetry of a theory dictates its form.
34:55: He presents Newton's musings on nature's self-similarity. Nature "is consonant to herself. She observes the same method in regulating the motions of smaller bodies which she doth in regulating those of the greater."
37:45 This self-similar property of nature is not a construct of the human mind. It is a property that any intelligent life would discover.
38:23 He remarks that Newton, in his time off, worked on his theory of gravitation, the laws of motion, calculus, and the composition of white light. He encourages research students to emulate Newton's productivity.
40:18 Eugene Wigner wrote an article on the unreasonable effectiveness of mathematics, which may be a consequence of Nature's self-similarity.
46:53: Questions. He briefly discusses his "decoherent histories" approach to quantum mechanics (my favourite approach btw) and compares it to the Many-worlds interpretation.