kottke.org posts about time travel

Rules for time travelers

posted by Jason Kottke   May 20, 2009

Sean Carroll lays out the rules for time travel for movies (but also more generally) based on our current understanding of physics.

1. Traveling into the future is easy. We travel into the future all the time, at a fixed rate: one second per second. Stick around, you’ll be in the future soon enough. You can even get there faster than usual, by decreasing the amount of time you experience elapsing with respect to the rest of the world — either by low-tech ways like freezing yourself, or by taking advantage of the laws of special relativity and zipping around near the speed of light. (Remember we’re talking about what is possible according to the laws of physics here, not what is plausible or technologically feasible.) It’s coming back that’s hard.

Survival tips for the Middle Ages

posted by Jason Kottke   Jun 10, 2008

I spend far too much of my life daydreaming about scenarios like this:

I wanted to ask for survival tips in case I am unexpectedly transported to a random location in Europe (say for instance current France/Benelux/Germany) in the year 1000 AD (plus or minus 200 years). I assume that such transportation would leave me with what I am wearing, what I know, and nothing else. Any advice would help.

To which Tyler Cowen replies:

Find someone who will take care of you for a few days or weeks and then look for employment in the local church. Your marginal product is quite low, even once you have learned the local language. You might think that knowing economics, or perhaps quantum mechanics, will do you some good but in reality people won’t even think your jokes are funny. Even if you can prove Euler’s Theorem from memory no one will understand your notation. I hope you have a strong back and an up to date smallpox vaccination.

The comments are full of informative and entertaining options. I side with the commenters who feel that the most likely outcome is death within a few days. Unless you’re skilled at wilderness survival, finding edible food, shelter, and potable water in a time when those things were much more scarce than now will prove difficult. If you do manage to survive, maybe you could set up shop selling goods that people could use:

I’d start a shop that did nothing but boil water and then sell it. I’d market it as “de-spirited” water and sell it to midwives, priests, doctors - anyone who would be charged with the health of another. The boiled, micro-organism free water would dramatically improve the health outcomes for anyone with cholera or plague or infection. Even marginally better outcomes using clean water would bolster my reputation and business. Of course, barriers to entry would be pretty low in my business, but if I were widely copied, I’d start a health revolution. For that quantum timeline anyway.

Again, assuming you survive, other commenters suggest that you “invent” something, sell it, and become rich so that your wealth will insulate you from further problems, stuff like gunpowder, mass production, long bows, guns, soap, steel, the printing press, double-entry accounting, whiskey, capitalism, and hot air balloons. I’m skeptical of this approach…how many people living in the US know how to make gunpowder from scratch? Given enough time, I guess I could build a hot air balloon that actually flies and carries human passengers but anything involving chemistry would prove tougher.

How would you survive if suddenly transported back to 1000 AD? Leave your suggestions for survival in the comments.

Temporal anomalies in time travel movies, an

posted by Jason Kottke   Jun 15, 2007

Temporal anomalies in time travel movies, an investigation of how time travel is represented in movies like Donnie Darko, 12 Monkeys, and Back to the Future. (via joshua)

Intro for Voyagers, a TV show from

posted by Jason Kottke   Mar 21, 2007

Intro for Voyagers, a TV show from the 80s about time-travelling do-gooders. I loved this show when I was a kid, but it seems to have not aged well. (via cyn-c)

An incredibly detailed description of the eight

posted by Jason Kottke   Dec 01, 2006

An incredibly detailed description of the eight different timelines in the three Back to the Future movies.

Spielberg’s new film…a wormhole movie based

posted by Jason Kottke   Jun 22, 2006

Spielberg’s new film…a wormhole movie based on the work of Kip Thorne?

Bill and Ted’s Excellent Adventure

posted by Jason Kottke   Jun 02, 2006

I know I’m going to get mail about my five-star rating for this movie, but it cannot be helped. One summer when I was a kid, a friend and I watched Bill and Ted’s Excellent Adventure — no joke — every single day for a span of 2 months. I still know every line by heart, the timing, inflection, everything. If there were a Broadway production of this movie, I could slide effortlessly into the role of either Bill S. Preston, Esq. or Ted Theodore Logan, no rehearsal needed.

In my high school physics class my senior year, we had to do a report on something we hadn’t learned about in class — which, I discovered when I got to college, was a lot — and I did mine on time travel. I went to our small school library and read articles in Discover and Scientific American magazines about Stephen Hawking, Kip Thorne, quantum mechanics, causality, and wormholes. To illustrate the bit about wormholes, I brought in my well-worn VHS tape of Bill and Ted’s (a dub of a long-ago video rental) and showed a short clip of the phone booth travelling through space and time via wormhole. I got a B+ on my presentation. The teacher told me it was excellent but marked me down because it was “over the heads” of everyone in the class…which I thought was completely unfair. How on earth is Bill and Ted’s Excellent Adventure over anyone’s head?