I think you're right. Even if we classify classical Chess as 3D (2D board + a time axis for game states), time travel re-uses that same time dimension.
If you wanted to shift the complexity into ludicrous speed (this is inspired by archgoon's comment [0]), you could introduce another dimension by putting a classical chess board inside each square of the 4D board. The 4D move only succeeds if you win the game on the mini-board. Just, please, don't bring recursion into this, unless you're captain Kirk and absolutely need to nerd-snipe a rogue AI. (“They've gone to plaid!”)
There's another possibility I've hinted at by calling standard Chess ‘classical’. On second thought, let’s not go to Quantum Chess. 'Tis a silly place. (I tried to imagine what a Schrödinger's king would look like. I've seen things you people wouldn't believe. Queens checked en passant from the future. I watched knigths glitter in the parallel time-line near the Hadamard Gate. All those moments will be lost in time, like tears in rain. Time to resign.)
How do you reckon that? I mean, it makes sense on an intuitive level; however, since now we're not talking about Conor Petersen's 5D chess, but the vast space of possible multiverse time travel chess variants, it's not obvious how one could prove this to be impossible in a somewhat rigorous way. For example, what if time-lines end when a king is mated (or wioll fore-when haven been mote [0]), but you only lose when you can't make a valid move in any time-line?
When there are multiple parallel time-lines, you have to input a move for each one before you can advance to the next turn. But to win, you have to mate just one of the opponent's kings. One player can have multiple kings on one board, because they can move through time and between time-lines.
I have no idea what high-level play will end up looking like, but the streamer from whom I learned the above [0] said that the most common way to win is to mate a king on a board in the past. Those already have their options of escaping an attack restricted by ordinary chess rules; it gets worse when you can make additional threats from the future.
That's depressing, but I will remember that when I come across an unnecessarily AMPified URL, I shouldn't blame the publisher for making this possible in the first place.
> If I search "Non-standard evaluation in left-hand side of mutate command R", it's a bit weird that I'm expected to click the first StackExchange rather than getting a canonical answer excerpted.
Are you saying that there's no excerpt at all above the search results, when you expected one; or that there is an excerpt, but it's not from the most appropriate/relevant source?
It's annoying when there's a page that has all the information you might need, but to find it, you first have to scroll past a bunch of Stack Overflow posts that are more suitable for dilettantes who prioritise trying a quick fix over learning best practices. But when you do make the effort to find the most promising link and your browser allows the search engine to record your choice, you at least get a vote regarding how the ranking should be adjusted. When users just look at the results but don't interact with them any further, that feedback vanishes.
A win for Google isn't necessarily a win for Google users.
I think you're right. Even if we classify classical Chess as 3D (2D board + a time axis for game states), time travel re-uses that same time dimension.
If you wanted to shift the complexity into ludicrous speed (this is inspired by archgoon's comment [0]), you could introduce another dimension by putting a classical chess board inside each square of the 4D board. The 4D move only succeeds if you win the game on the mini-board. Just, please, don't bring recursion into this, unless you're captain Kirk and absolutely need to nerd-snipe a rogue AI. (“They've gone to plaid!”)
There's another possibility I've hinted at by calling standard Chess ‘classical’. On second thought, let’s not go to Quantum Chess. 'Tis a silly place. (I tried to imagine what a Schrödinger's king would look like. I've seen things you people wouldn't believe. Queens checked en passant from the future. I watched knigths glitter in the parallel time-line near the Hadamard Gate. All those moments will be lost in time, like tears in rain. Time to resign.)
[0] https://news.ycombinator.com/item?id=24064974