Everyone understands time, and no one knows how it works. And that may be the least contradictory thing about something that feels like a solid, inflexible part of reality, but consistently bends under the weight of culture and psychology. To live is to time travel and people experience that trip in different ways, but no one can reverse course or alter speed — a collective dream since H.G. Wells published The Time Machine in 1895. Author James Gleick wanted to know why, so he dug in, talking with philosophers and black hole-hunting theoretical physicists.

Though his book, Time Travel: A History, fails to offer practical tools for chronological self-determination, it does offer readers the opportunity to grapple with one of the few remaining restraints on human movement. Gleick spoke to Inverse about pulling on that last restraint.

Time Travel isn’t a new topic, and it isn’t a reality, so why does it fascinate us? Is there anything in particular about being a human in 2016 that draws us to the idea of time travel?

When I started the book, I did have in the back my head that sort of wacky, speculative idea that maybe time travel was basically over. That it had run its course and all the things that needed to say had been explored. That was in 2011 or 2012 — now I just think that’s a stupid thing to have thought, because that’s not what happened at all. As I was working on this book, incredibly interesting new variations on the theme of time travel appeared. Even this Fall I think there are at least three network television shows that have a time travel theme.

Why is this? Because our relationship with time is as froth, intense, and anxiety producing as ever. Probably even more so than before because everything in the world is going so fast — all the complications and confusions that come from living in a network existence, where we are getting information on multiple channels. Those channels come to us as though they are a part of our present. We’ve gotten good at different versions of time shifting, like instant replay or tape delay. So, for better or for worse, we’re filling our lives with things that resemble time travel. No wonder we are still interested in it.

Doctor Who's Tardis is England's most prominent modern time machine.

Do you think our perception of time will change or has?

I’m comfortable believing that we are never going to arrive at any kind of complete, final, satisfactory answer to what time is. I’m constantly resisting the bumper sticker slogans as to what time is, sayings like “time is what happens when nothing else does” and “time is nature’s way of keeping everything apart.” I love them, but I resist them.

There are serious physicists trying to answer the question of what time is. They are the ones with the official answer, if you believe in science, like I do. But I also believe that there is no official answer, and that the physicist’s version of time is only a part of the picture. We also have psychological time, which is different from that.

It’s my view that we have to accept that we have a very complicated view of something that we expect to understand simply.

Your book makes the case that literal time travel, as in going back and forth in time, is impossible exist. Did you encounter any scientists in your research who disagreed?

Yes. Lots. As you say, my view is that the literal view of time travel is an impossibility. I say that because of my view of what time is. There are people who don’t agree with me and I hope there are many of them because I’m raining on my own parade.

The kind of person most likely to say, ‘Well, we can’t be sure that time travel is impossible’ is your modern, up-to-date, theoretical physicist. There are lots of them who want to remain open to the possibility of time travel and they are a lot smarter than I am. I have a great respect for the way they think about these issues.

There are also theoretical physicists who think that a literal understanding of time travel implies a kind of view of reality that probably isn’t the right one — mainly, that the future is already there in some way, waiting for us to arrive in our machine. Or, that the past is also still there in some way and it’s not irretrievably gone so, if you had the right kind of machine or portal, you could go there. I don’t think that’s how it is and I think in their heart of hearts, most physicists don’t either. It’s just that with equations and models for reality, it’s hard for them to rule it out.

I appreciate a scientist who likes to keep an open mind.

The American answer to England time-traveling police box is, naturally, a car.

When I was reading your book, it dawned on me that people probably wouldn’t want to time travel if they realized it would most likely mean they would slip into a black hole and hope that a worm hole would spit them out. That’s less appealing than jumping in a pod and going to 1920s Paris.

That’s right. We want there to be a good glass of wine waiting for us at the other end and to have the chance to talk to F. Scott Fitzgerald.

Exactly. Do you think that popular culture will ever shift, and portray this more realistic version of time travel? Much of what we receive now seems to be a regurgitation of H.G. Wells’s The Time Machine.

Of course — and that’s good. That’s what attracted me to the subject in the first place. Even if I don’t think that we’re literally able to get into a time machine, I do think that it’s a real and powerful way of thinking about the world and helps us.

A recurring theme in my book is how time travel presentation has paralleled the evolution of ideas in popular culture and in science. H.G. Wells said that time in the fourth dimension was a gimmick, a trick that he was playing to get the reader to believe his story.

He didn’t imagine that, 10 years later, this German fellow Albert Einstein would be putting forward a whole theory of the universe in which it’s very useful to view time as a fourth dimension. That would in fact become modern orthodoxy. It’s not because Einstein read “The Time Machine*; it’s because they were both living in the same universe where, for many reasons, it was becoming more natural to think of time as space.

If you went back in time and saw the 2002 movie 'The Time Machine' than someone would have.

But even Einstein couldn’t nail down time.

Advances in physics during the last century have increased our knowledge of the world we live in, to an astonishing degree and — it can’t be underestimated — contributed to answering philosophical questions about the nature of reality. It’s interesting that, to an extent, these questions are still wide open.

This interview has been edited for length and clarity.