There’s an installation near the Shuttle, but explore a little further down an obscure hallway to the Bryant Park station and there’s even more.

Tech companies are revamping computing — from how tiny chips are built to the way they are arranged, cooled and powered — in the race to build artificial intelligence that recreates the human brain.

At the height of their offensive, Ukrainian forces controlled some 500 square miles of Russian soil. Now they hold just a ...