Infinities := means is defined to equal.

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Discussion Overview

The discussion revolves around the concept of infinities in mathematics, particularly in relation to cardinal numbers and their definitions. Participants explore the implications of these definitions in the context of chess games, questioning whether the maximum number of moves in a chess game is finite or infinite. The scope includes theoretical considerations of cardinality, mathematical reasoning, and conceptual exploration of game states.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants define the notation := as "is defined to equal," and elaborate on various cardinal numbers and their relationships.
  • One participant questions the maximum number of moves in a chess game, suggesting that the finite nature of the board and pieces might imply a finite number of games.
  • Another participant proposes a related question about the number of distinct legal chess games and the percentage of those that end in draws, noting that infinite cycling of pieces could lead to an infinite number of games.
  • Some participants mention the triple repetition rule in chess, arguing that it ensures games end after a finite number of moves due to the limited number of game states.
  • One participant suggests an upper bound for the number of chess games based on binomial coefficients, estimating it to be in the range of 10^43 to 10^44.
  • Another participant reflects on the implications of a perfect player in chess, suggesting that this could lead to a finite number of games.

Areas of Agreement / Disagreement

Participants express differing views on whether the maximum number of moves in a chess game is finite or infinite. While some argue for finiteness based on game rules, others suggest that infinite cycling could lead to an infinite number of games. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants reference various mathematical concepts and definitions without reaching consensus on the implications for chess games. The discussion includes assumptions about player behavior and game rules that may affect the conclusions drawn.

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infinities := means "is defined to equal."

:= means "is defined to equal."

x_y means y is a subscript of x.

N:={0, 1, 2, ...}

[P,0](S):=S
[P,1](S):={x : x is a subset of S}
for n >= 1,
[P,n+1](S):={x: x is a subset of [P,n](S)}

card(S) is the cardinal number of S.

1_n:=[P,n](N).

aleph_n := card(1_n).

2_1:={x: x is an element of 1_n for some n in N}; i.e., 2_1 is the union of {[P,0](N), [P,1](N), [P,2](N), ...}.

what is card(2_1)?

for n>=1,
2_(n+1):={x: x is an element of [P,k](2_n) for some k in N}; i.e., 2_(n+1) is the union of
{[P,0](2_n), [P,1](2_n), [P,2](2_n), ...}.

what is card(2_n)?

3_1:={x: x is an element of 2_n for some n in N}.
for n>=1,
3_(n+1):={x: x is an element of [P,k](3_n) for some k in N}.

what is card(3_n)?

for m>=1,
(m+1)_1:={x: x is an element of m_n for some n in N}
for n>=1,
(m+1)_(n+1):={x: x is an element of [P,k](m+1_n) for some k in N}.

what is card(m_n)?

[1]:={x: x is an element of m_n for some m,n in N}.
for n>=1,
[n+1]:={x: x is an element of [P,k]([n]) for some k in N}.

what is card([n])?

[N,1]:={[n]: n is an element of N}.
for k>=1,
[N,k+1]:={[n]: n is an element of [P,j][N,k] for some j in N}.

what is card([N,k])?
 
Last edited by a moderator:
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Originally posted by phoenixthoth
:= means "is defined to equal."

x_y means y is a subscript of x.

N:={0, 1, 2, ...}

[P,0](S):=S
[P,1](S):={x : x is a subset of S}
for n >= 1,
[P,n+1](S):={x: x is a subset of [P,n](S)}

card(S) is the cardinal number of S.

1_n:=[P,n](N).

aleph_n := card(1_n).

2_1:={x: x is an element of 1_n for some n in N}; i.e., 2_1 is the union of {[P,0](N), [P,1](N), [P,2](N), ...}.

what is card(2_1)?

for n>=1,
2_(n+1):={x: x is an element of [P,k](2_n) for some k in N}; i.e., 2_(n+1) is the union of
{[P,0](2_n), [P,1](2_n), [P,2](2_n), ...}.

what is card(2_n)?

3_1:={x: x is an element of 2_n for some n in N}.
for n>=1,
3_(n+1):={x: x is an element of [P,k](3_n) for some k in N}.

what is card(3_n)?

for m>=1,
(m+1)_1:={x: x is an element of m_n for some n in N}
for n>=1,
(m+1)_(n+1):={x: x is an element of [P,k](m+1_n) for some k in N}.

what is card(m_n)?

[1]:={x: x is an element of m_n for some m,n in N}.
for n>=1,
[n+1]:={x: x is an element of [P,k]([n]) for some k in N}.

what is card([n])?

[N,1]:={[n]: n is an element of N}.
for k>=1,
[N,k+1]:={[n]: n is an element of [P,j][N,k] for some j in N}.

what is card([N,k])?

Good evening phoenixthoth
I wish i could answer you, maybe in my next life when i am a math wiz. I will leave that to someone else.

Could you calculate me this> Is the maximum amount of moves in a chess game finite? If so how many. The board is limited to 64 spaces that are finite, there are 32 pieces that are finite plus new pieces that are finite and last but not least the amount of moves each piece could make in relation to the others. Can you get infinity from fixed variables? or is there a finite number of games?
 
i've been thinking about this question, or a related question, on and off, for a while now. the question i was thinking about is how many distinct legal chess games are there in which each player made any possible legal move and what percentage of those games are draws? one game would be considered distinct from another if, for example, a bishop was moved two spaces instead of one.

the wording is slightly different, but tell me if our questions are the same.

i just realized that the answer to my question is infinite because the knight (and most pieces) can cycle back and forth between two positions indefinitely.

i guess a related question is how many different games are there if infinite cycling is prohibited? the rub is that sometimes infinite cycling is inevitable though these are when draws occur. so i guess the question could be rephrased to ask what percentage of chess games don't end in infinite cycling?

***

what I'm trying to get at with the original post is that there is a cardinal bigger than all the alephs. from this cardinal, a list of bigger cardinals can be constructed. then there is a cardinal bigger than all those on that list. and so on forever. my ultimate goal is to try to find something bigger than all cardinals but that's impossible.
 
Last edited:
You forget the triple repetition rule; if a game state is repeated 3 times, the game is a draw. Since there are only a finite number of game states, this ensures a game ends after a finite number of moves.
 
if (x y) is the binomial coefficient then an upper bound should be in the ballpark of Sum( (64 x) , {x,2,32} ) which is in the ballpark of 10^43 - 10^44.
 
Originally posted by Hurkyl
You forget the triple repetition rule; if a game state is repeated 3 times, the game is a draw. Since there are only a finite number of game states, this ensures a game ends after a finite number of moves.

Also there is a finite number of good moves of which if you are playing against a no mistake player, you will not make a second move.
 
Originally posted by phoenixthoth
if (x y) is the binomial coefficient then an upper bound should be in the ballpark of Sum( (64 x) , {x,2,32} ) which is in the ballpark of 10^43 - 10^44.

So we found something interesting tonight, the amount of games may be the plank length 10^43
 
i just realized that the answer to my question is infinite because the knight (and most pieces) can cycle back and forth between two positions indefinitely.

I think you may have to consider this> Also there is a finite number of good moves of which if you are playing against a no mistake player, you will not make a second move. If you use that variable a perfect player, the amount of games have to be finite.
 

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