Chess will never be solved, here's why

As you point out, @llama36, only the choices of one side contribute to the number.

Empirically there are not only a lot of legal moves for the defender, there are very often several reasonable moves (the number 4 is one conservative estimate for a typical number of non-blunders in positions in empirical chess).

Interesting

Much earlier in conversation i.e. years ago, when three moves were suggested as an average, I preferred four, which seems to have been borne out.

H

@6636

"Are you saying you can square root the positions because we're assuming we can ignore all non-optimal play by black?" ++ We can even discard optimal play by black. Suppose both 1 e4 e5 and 1 e4 c5 draw. To weakly solve chess it is possible to look only at 1 e4 e5 and discard 1 e4 c5.

"How do you discard non-optimal moves without analyzing them?"
++ By the end result. If all lines end in a draw 7 men-table base endgame position or a prior 3-fold repetition, then that retroactively validates all black moves as optimal.

     I believe there is an old aphorism concerning the color of pots and kettles that might apply here.

@6635

"What weak chess players call "relevant" has no place in weakly solving chess, as indicated by it having no place in the academic literature."
++ Check Schaeffer's solution of checkers: only 10^14 positions relevant of the 5*10^20 legal.
Only 19 of the 300 openings relevant.

I'm afraid I don't think it applies & there's no need for that kind of pedantry. Save it for someone who can learn from it, perhaps.

@6640

"No matter how eloquently you argue for the 10^17 reduction, after realizing this you have to go back and figure out how it's wrong."
++ 10^17 is not wrong. Chess is just not as deep and as wide as some people seem to think.
However 10^17 is still a huge number.
3 powerful computers working 24/7 during 5 years is huge.

     It might seem that the fact you immediately replied with more of the same might indicate that it does apply. I certainly never believe that some posters are capable of learning much.

If I had to solve chess, I wouldn't employ tygxc. That's a given. I'd rather employ Elroch because he tends towards caution. But if it's capable of being solved, it wouldn't be by someone who tends too far towards caution, either and someone who finds he cannot claim that he knows
1 e4 e5 2 B a6 loses tends far too far towards caution.

So I'd employ my son, who's managing a team of data scientists at the moment, to set it up. To tempt him to do so, I suppose I'd have to pay him £140,000 a year. And then maybe a team of five data scientists, at, say £40,000 to £60,000 a go, depending on expertise. At least one grandmaster. One might be got for £70,000 year. Let's see: that seems to be £460,000 per year for five years, which is 2.3 million, which translated into dollars is about $2.9 million in five years in wages alone.

How much does tygxc think it will cost for the entire thing, again?

No, not at all. You're surely not denying that you're being ridiculously pedantic, concerning an argument that was finished with yesterday? So I was just being truthful. Stick to what you're good at.

Ooh, $3million, leaving $100,000 for equipment, possible consultancy fees and other contingencies. I think we have to dispense with two of the data scientists and get my son for less. Would he do it for £120,000 per year? I doubt it, actually. It would be a pay rise but it would lead nowhere if the project was unsuccessful and with such limited resources it won't succeed more than likely and I doubt he would do it for that. Not if he has any sense. Whoever leads it is going to lose five years of time, possibly at the most productive time in their lives, which could really lead somewhere exciting. I have a bad feeling about this already. Count me out, in fact. Nothing even in it for me.

     Just pointing out that someone who insists on misinterpreting another poster's use of the term "car", going off on on long sidetracks on that point, and then complaining that someone else noticing said mistake is reacting inappropriately is in fact acting inappropriately.

     It's likely most people here don't care for or pay much attention to those who assume the mantle of arbiter of acceptable posting.

Daft as a brush.

Let's say there are two chess-playing super computers that have equal processing power. Neither has an advantage over the other in CPU speed or in any other parameter by which computers can be compared. They are also running the identical chess engine. What could possibly be the explanation for one computer defeating the other? Is that even possible?

There are plenty of examples of Leela vs Stockfish, AlphaZero vs Komodo, Fritz vs Leela, etc... But I have never seen Stockfish vs Stockfish on identical computing platforms. 

Programmed differently. If they were programmed the same then would probably be a draw unless one won due to a coincidence regarding "visible horizon" of predictable moves.

As has been pointed out in the past, engines that are "identical" in software and hardware configuration parameters still run on different hardware under different software instances, and variances will occur.

If you have ever overclocked a CPU, then you will know that CPUs that are supposed to be identical...are not.  They are built to fall within tolerances.  Software running on an OS is subject to variances in resource sharing and interrupts, etc.  The programming *is* the same for identical releases, for the record.

Much of the bad information on this thread comes from people who seem to know diddly and squat about computers, Tygxc included.

IM Levy Rozman did an interesting experiment that comes close to what I was talking about above (Stockfish vs Stockfish) but he forced a particular opening sequence before allowing them to play. He thinks that if he hadn't done that, that the computers would simply play a Ruy Lopez to a draw every time. But, would they? I would find it much more interesting if the engines were allowed to calculate from move #1. And, even if most games resulted in a draw, what could possibly be the explanation for any game ending *not* in draw?
https://www.youtube.com/watch?v=Vq-iWlbqX-0

Cause every hand a loser, and every hands a winner, and the best that you can hope for is to die in yer sleep..

https://youtu.be/7hx4gdlfamo