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The Physics of Time Travel: a TY module

Who isn't fascinated by time travel? Whether on a fun 'Back-to-the Future' level with flux capacitors et al, or on a deep dive into special and general relativity, it is endlessly interesting stuff. And the need to come up with something that involved little practical work but was still interesting encouraged me this autumn to stick together a few bits and pieces I've used over the years to create a TY mini-module on the topic. It takes me about 4 classes to get through it, (though that can expand or contract easily enough.)

It follows various digressions from the central theme that indulge my own interests - but that seem to keep kids onboard. One thing that can't really be separated from the idea of time travel are thoughts about what the future might look like, which leads to all sort of speculation about amazing future technologies, and which links in turn back to the problem of climate change and that all that implies for our use of technology.

I've included a section that brings us right into the maths of time dilation and special relativity. I was inspired to do this by a presentation at Frontiers a few years back about circular motion: I don't remember the lecturer's name, but he made the point that we're too inclined to hold back on sharing physics ideas with the general public because they're complex - but the endless complexity of genetic inheritance doesn't stop biologists from sharing their ideas about DNA. With the end result that nearly every child knows at least something about DNA and almost nothing about modern physics.

The maths of time dilation only needs a junior cert knowledge of algebra, Pythagoras and distance-speed-time calculations to (more or less) follow. I find most kids will stay with it as long as I promise them there will be no tests and all they have to do at the end is stick a few numbers into their calculator and fill in an answer book. And I grade the book more on a willingness to engage than on a marks-out-of-ten basis.

Scroll down to the bottom here for the PowerPoint and Word docs that I use. They're all open to whatever changes might suit, and if anybody wants to adapt them to take the module in a different direction, please fell free to send your files back to me and I'll stick them up too.

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