“We’re still trying to figure out what time is,” Gleick said. Time travel stories apparently help us. The inventor of the time machine in Wells’s book explains archly that time is merely a fourth dimension. Ten years later in 1905 Albert Einstein made that statement real. In 1941 Jorge Luis Borges wrote the celebrated short story, “The Garden of Forking Paths.” In 1955 physicist Hugh Everett introduced the quantum-based idea of forking universes, which itself has become a staple of science fiction.
“Time,” Richard Feynman once joked, “is what happens when nothing else happens.” Gleick suggests, “Things change, and time is how we keep track.” Virginia Woolf wrote, “What more terrifying revelation can there be than that it is the present moment? That we survive the shock at all is only possible because the past shelters us on one side, the future on another.”
“Enjoy the present. Don’t waste your brain cells agonizing about lost opportunities or worrying about what the future will bring. As I was working on the book I suddenly realized that that’s terrible advice. A potted plant lives in the now. The idea of the ‘long now’ embraces the past and the future and asks us to think about the whole stretch of time. That’s what I think time travel is good for. That’s what makes us human — the ability to live in the past and live in the future at the same time.”