Greg Egan is the best hard sci-fi writer in my opinion. His works like _Diaspora_, _Permutation City_, and _Schild's Ladder_ are based on very high level physical concepts and are amazing reads. Start with his short story collection _Axiomatic_ if you haven't read it, I can bet that every HN reader will like it.
His blog articles often go over my head and I admit that I usually understand only the first ~30-50%, after which I give up.
His blog articles often go over my head and I admit that I usually understand only the first ~30-50%, after which I give up.