One thing I'm facinated by is the concept of revolutionary ideas that are purely intellectual. Gleick's last book, The Information, brought this particularly into focus regarding language, (as did Jared Diamond in Guns, Germs, and Steel in describing the development of written language, particularly the Cheroke co-opting of latin forms). Abstract ideas like language or math don't depend necessarily on technology in order to be thought of, or made useful to humans, they can theortically just be thought of in an epiphany moment. Time Travel is apparently on of those ideas. Before reading this book I would have assumed that the idea of travelling into the past or future has been around as long as language itself. Surely there must be old myths of time travelling gods, right? Wrong. Time travel as an idea wasn't popular, or documented, prior to Orsen Wells' Time Traveller in the 1890's. That's incredible to me. Money quote:
Time travel feels like an ancient tradition, rooted in old mythologies, old as gods and dragons. It isn’t. Though the ancients imagined immortality and rebirth and lands of the dead time machines were beyond their ken. Time travel is a fantasy of the modern era. When Wells in his lamp-lit room imagined a time machine, he also invented a new mode of thought. Why not before? And why now?
...
How strange, then, to realize that time travel, the concept, is barely a century old. The term first occurs in English in 1914—a back-formation from Wells’s “Time Traveller.” Somehow humanity got by for thousands of years without asking, What if I could travel into the future? What would the world be like? What if I could travel into the past—could I change history? The questions didn’t arise.
Gleick spends a little time actually answering those questions, but not nearly enough. (Short answer is that life just didn't move fast enough prior to the industrial revolution to really think that either the past or the future were significantly different from the present, so it just wasn't a common thought. Combine that with time zones (new after railroads) and you have a society that is much more aware of time as a concept than any before it).
More good stuff:
“Mere shadows,” Minkowski said. That was not mere poetry. He meant it almost literally. Our perceived reality is a projection, like the shadows projected by the fire in Plato’s cave. If the world—the absolute world—is a four-dimensional continuum, then all that we perceive at any instant is a slice of the whole. Our sense of time: an illusion. Nothing passes; nothing changes. The universe—the real universe, hidden from our blinkered sight—comprises the totality of these timeless, eternal world lines. “I would fain anticipate myself,” said Minkowski in Cologne, “by saying that in my opinion physical laws might find their most perfect expression as reciprocal relations between these world lines.”
This is inline with how I've come to think of the world over the last few years.
When his friend Besso died in 1955, Einstein consoled his family with words that have been quoted many times: Now he has departed from this strange world a little ahead of me. That means nothing. People like us, who believe in physics, know that the distinction between past, present, and future is only a stubbornly persistent illusion. Einstein died three weeks later.
Great quote.
Sebald also asked, “In what way do objects immersed in time differ from those left untouched by it?” This was a nice conceit: that some parts of our world, like dusty, shuttered rooms, may stand outside of time, may be cut off from time, immune to the flow.
I've often felt that isolated places somehow sit outside of time. This past weekend I was in an old electrical closet that was rarely used, in an old, pitch black space. Being inside there, I felt aware that no one had been there in quite some time. When I left that room, in a sense, was time stopping inside of it? Reading Lee Smolin (cited extensivly in this book) brought that even more in focus. Does time, or space, exist at all without a conscious being to experience it? Is everything just Schrodinger's cat?
Not sure much else good stuff was in here. Plenty of good quotes, but not sure there were really any big ideas. The book was fine, and interesting, but in a sense it is almost a literary review of time travel in pop culture. Gleick spends a lot of time, most of the book, just reviewing popular fictional works related to time travel.