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Re: starship-design: Irrational Odds

Ken Wharton wrote:
>Isaac writes:
>>>You can do an experiment of asking people how they're doing.  A
>>>large portion of them will actually respond by saying "fine" or whatever,
>>>even though the odds of everyone "randomly" behaving this way (and not
>>>saying random words, clawing your eyeballs out, etc.) are inconceivable.
>>>Every time you can even somewhat-accurately predict how someone will 
>>>to a given set of circumstances, you are helping to refute the infinite-
>>>universe possibility.

>>Here you demonstrate how little you understand about probability and
>>what it means to be a random event.

>>Consider a hypothetical lottery which is randomly determined.  You
>>buy one of those tickets.  Whether you win or not is random, and
>>yet the most likely result is that you lose.  Just because something
>>is random doesn't mean the chances are 50-50.

>>Similarly, if you go up to John Smith and ask him how he's doing.
>>Most of the time he'll say "fine".

>Ahhh - but once you start thinking in terms of multiple universes, you lose 
>the idea of probability.  What does it mean to have one universe that is 
>less probable than another?  If a universe exists it's probability is one; 
>the only probability involved is Which universe we happen to find ourselves 
>in right now.  And that would mean that there have to be a lot of identical 
>universes where John Smith says "fine" for every universe in which he says 
>"hovercraft" just to make the odds turn out right. 

If a universe exists, its probability of existing is indeed 1.  So?
If we can never access that universe, what difference does that make?
BTW, out current understanding doesn't just involve 1 or two or a
million million million simultaneous possibilities--it involves an
infinite continuum of possibilities.  It's not even a countable

>But that leads to more problems.  Suppose you have a quantum event that has 
>a 1/pi chance of coming out A, and a (1 - 1/pi) chance of coming out B.  If 
>the universe really splits off into alternate possible universes for each 
>outcome, with each of the universes as "real" as the others, then there's 
>no way to do it.  Even if you have lots of universes, because pi is 
>irrational there's no way to make the odds come out correctly.  

Wrong.  Consider the act of choosing randomly from [0,1] with the
Lebesgue probability distribution.  The probability of picking a
number in [0,1/pi] is exactly 1/pi.

I'm not about to go through the trouble of teaching you measure theory
and probability theory.
    _____     Isaac Kuo kuo@bit.csc.lsu.edu http://www.csc.lsu.edu/~kuo
/___________\ "Mari-san...  Yokatta...
\=\)-----(/=/  ...Yokatta go-buji de..." - Karigari Hiroshi