2 moves as black:
1f4 d6(or d5). 2.g4 Qh4++
George
The shortest mate!
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georgecaplan wrote:
2 moves as black:
1f4 d6(or d5). 2.g4 Qh4++
George
1. Qh4 is an illegal move. You obviously mean e6 or e5, not d6 or d5.
2. Anyways, this is not the shortest mate. Just the fewest moves. ;)
What do you mean by 'shortest'?
The only guess that came to mind is the shortest move of a piece that delivers mate, but that could be any piece that mates by moving one orthogonal square [Rook, pawn, King, Queen]. So I don't think that's it.
Shortest is a geometrical term.
The shortest mate is therefore the mate with the shortest distance of all piece movements.
Scholar's mate 1. e4 e5 2. Qh5 Nc6 3. Bc4 Nf6 4. Qxf7 for example has a length of 1 + 1 + sqrt(32) + sqrt(5) + sqrt(18) + sqrt(5) + sqrt(8) = 24.37
Fool's mate 1. f4 e6 2. g4 Qh4 has a length of 2 + 1 + 2 + sqrt(32) = 10.66
Now which is the SHORTEST mate possible?
:)
perhaps?
Round of applause.
Hm, that was pretty stupid.
Caiellos solution is nice, but certainly not shortest.
sqrt(5) + 1 + sqrt(5) + sqrt(5) + 1 + 1 + sqrt(5) = 11.94. This is way too long.
The correct solution is less than 9.5 square-units.
EDIT: Just seen how it's calculated, just pure nonsense.
1.f3 e6 2.h3 Qh4+ 3.g3 Qxg3#
@Ziryab: your solution is still much too long with more than 11 square units.
I repeat: The correct solution is less than 9.5 square units!
Shortest fool's mate (1. f3 e6 2. g4 Qh4#) is 9.66 square units.
Come on guys, I needed 5 minutes to solve it. YES, YOU CAN do this as well! :)
It's stupid though, in fools mate the queen moves 5 squares, yet the calculation is the root of 32.
It's a half arsed pun attempt with no real relation to the moves being played on the board.
The route isn't the number of squares the queen can go to, it's the number of squares the queen does travel.
How about Caiello's idea reversed:
which is 4*sqrt(5) + 2.
Only 10.94 units, so not under 9.5 I guess. This is difficult!
this is 2+2+3+1+2*sqrt(2) which is still over 10, and it seems pretty direct 
This is under 10, but not, I believe under 9.5!
This seems to be 9.24
AndrewB_Aus has solved the problem! 
A guy in another forum posted the following question:
"Which is the shortest possible route to mate?"
Tipp/Spoiler:
Don't suggest fool's mate. This is NOT the correct solution!