Matter

Topology is the branch of geometry that deals with large-scale features of shapes. One cliché is that a topologist cannot distinguish a doughnut from a coffee cup: if a coffee cup were made of rubber, one could continuously deform it to a...

Young children often pose the most interesting questions. “Why are we here?” is one of them. And this question can take on many forms. One of them is “Why is there anything at all?” Another is “Why am I alive?” or “Why am I me?”

These...