I have created a repository that has an OPML file containing an assorted list of different blogs that are worth following.
Majority of the blogs are related to Cryptography, CTF write-ups, Mathematics and a bit of Physics (Quantum computation, cryptography).
Just import the OPML file to your favourite RSS reader and it will work out-of-box. It might be the case that some of the blogs are no longer maintained actively by the author(s).
Contributions to the list are highly welcomed :)