Brian Shelf asked:
Firstly, I love the podcast. It's the right blend of basic facts blended with complex concepts which keep the amateur astronomer and scientist like me entertained, educated and never patronised. Thanks for all the ear candy for the last year and more I've been listening.
One of the basic assumptions of cosmology is the laws of physics as we know them hold true throughout the observable universe. What evidence is there for this?
I agree that the "Laws of Physics" should apply universally. However, it would be quite presumptuous to think that we now know all of the "laws of physics". Undoubtedly, some of our interpretations will be improved over time.
This is a simple question with a very complex answer and a simple one. --- Yes, but ... There is a hint that there might be a very tiny change in a critical relationship right back just about as far as we can see at the moment. More of that a bit later.