Knossos Games - Bathroom Tile

For the issue of "Imagine" celebrating Einstein, I wanted to come up with a puzzle related to one of his discoveries. My first idea, a puzzle about gravity, didn't quite work out, but my second idea of time travel was easier to do. Sort of.

The puzzle is simply one of order of operations. By claiming that later time travel blocks affect earlier ones in the sequence, I'm simply making the puzzle work like the standard order of operations that is used in day-to-day math. Thus, in order to create the puzzle, I'd simply need to pick out a few numbers and operations, and then reorder them in various ways However, as the number of operations increases, the number of combinations increases exponentially. In addition, you don't have to use all of the blocks, which increases the number of combinations as well. I wanted to make sure that I picked questions that required unique solutions, which meant generating all of the possible combinations and combing through them.

In order to do this, I created a computer program, somewhat similar to the one used for the bathroom tile and if/then city blocks puzzles. This would take the operations, order them every way possible, and simplify the functions. I then would go through the results and pick out the ones that were interesting.

While some of the questions require some trial-and-error, others can be solved by thinking about the consequences of ordering the operations in certain ways. This is especially true of the last question, where you want to find the furthest forward and backward in time that you can possibly travel.

Finally, a comment about time travel. Most of the time, in books and movies and television, time travel is treated as something that you have to be extremely cautious about. Traveling forward in time is fine, but traveling backward in time can be very dangerous – if you alter history, the present might get screwed up too. So I thought it would be funny if time travel were treated in the puzzle as something so harmless (and so technologically simple) that it was included in a children's toy. Yeah, be careful about altering the time line, but temporal practical jokes will be fun, that sort of thing.