COVID in the house? Oh no. You just slipped that in. I hope everyone is OK.
You and I are apparently fans of the same movies. Previously you referred to a Hitchhiker's Guide to the Galaxy. This week it's O Brother Where Art Thou. If you tell me you also are a fan of the The Blues Brothers (original, probably before your time), that's the trifecta of movie fandom.
Of all your blogs this one for me was the most completely and easily (there was nothing easy about it😇) understood. Knowledge is cumulative and your writing is great (and funny).
I believe I understand the basics, almost intuitively. There must be dark matter because otherwise the standard model doesn't work and the standard model has to work or the universe as we know it doesn't make sense.
I have a couple of question that arise not so much about your search for the elusive dark matter. One is about Newtonian physics. I thought Einstein's Theory of Relatively disproved Newtonian principles. And yet you say here that
In order to provide an explanation without enforcing Newton’s theory of gravitation to be incorrect, we need to assume that some invisible matter is present in our universe.
The second question has to do with black holes: I always associated dark matter (perhaps incorrectly) with black holes. Black holes (in the popular consciousness) are supposed to consume energy. However, in your blog you explain that
Two dark matter particles can annihilate into two Standard Model particles. That gives rise to cosmic ray and gamma ray signals that can be observed in satellite experiments orbiting around Earth.
So from the dark matter we can get energy? (Cosmic and gamma rays)
Now I recognize that I may be mixing apples and oranges. But, I'm at the stage of learning where I am associating ideas. In other words, your blog and your information is beginning to have real-world context for me, even if I'm on the wrong track 😆.
This is a great blog, @lemouth, and the summaries really do help.
Hope everyone in your house gets well soon, if they are not well now. Take care of yourself.
Regards,