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by **supermagictom** » Mar 21st, '07, 18:25

This is a strange coincidence, coz I've been obsessed with random numbers lately, heres a pretty cool site that gives you info on random numbers as well as some strings for yourself:

https://www.grc.com/passwords.htm

edit : if you press refresh in your browser you can see the strings change completely with no similarity between one string and another.

I use it for passwords for e-mail and forums etc, you can get some very strong passwords. (But you'll never remember them so it's a good idea to store it in a txt file on a encyrpted volume).

It's still not genuinely ''random'' though, but its as close as computers can get. Some computer based Random Number Generator's can pull data from places that are ''random'' in a way, for example an encryption program called TrueCrypt asks you to move the mouse as randomly as possible and it uses your mouse movements in the RNG. This brings in an incredibly hard to predict/replicate input to the RNG.

I definitely do believe that if you knew every single particle in the universe intimately, its exact energy,position,mass etc then you would be able to (theoretically) predict the future and know the past. Like the above quote mentioned from Stephen Hawkings book. But you would not necesserily have a computer fast enough (ever).

by **stepSeven** » Mar 21st, '07, 19:40

..definitely do believe that if you knew every single particle in the universe intimately, its exact energy,position,mass etc then you would be able to (theoretically) predict the future and know the past. Like the above quote mentioned from Stephen Hawkings book. But you would not necesserily have a computer fast enough (ever).

Wouldn't it have to be as big as the universe too?

I'm thinking to store the state of each 'particle' would take something as big as the universe even if you could store all that info in something the size of a 'particle'.

by **beeno** » Mar 21st, '07, 20:10

stepSeven wrote:Wouldn't it have to be as big as the universe too?

I'm thinking to store the state of each 'particle' would take something as big as the universe even if you could store all that info in something the size of a 'particle'.

And then you'd have twice as many particles as you started with, and you'd need another machine to monitor those particles. It would go on forever if the machine existed inside the universe it was monitoring.

by **Lawrence** » Mar 21st, '07, 20:16

I'm going to make a slight change to one of my previous arguements. it is not in any way necessary for a coin/dice/piece-of-buttered-toast to be evenly wieghted on all sides. even if the coin/... is wieghted in such a way that it gives one side a greater chance of being the outcome, then the outcome... is still random!
it's like with dice: the change of you rolling a 1, or anything else, now you've got a much greater change of rolling the "anything else" but the outcome of the 2 proposed outcomes is again... totally random

people have wierd ideas about randomness

by **Sir_Digby_Chicken_Ceaser** » Mar 21st, '07, 20:24

But its not random as we KNOW that theres more chance of the heavier side landing face down. This immediately cancels out any question of randon since it can be predicted and be right 7/10 times. The only "tails never fails" is because there is alot more metal on the queens head than the lion or whatever it is.

If someone said to me soomething was 100% magic then for this to be true i would say there had to be no human interference (or animal for that point) with it all.

by **supermagictom** » Mar 21st, '07, 20:38

stepSeven wrote:
..definitely do believe that if you knew every single particle in the universe intimately, its exact energy,position,mass etc then you would be able to (theoretically) predict the future and know the past. Like the above quote mentioned from Stephen Hawkings book. But you would not necesserily have a computer fast enough (ever).

Wouldn't it have to be as big as the universe too?

I'm thinking to store the state of each 'particle' would take something as big as the universe even if you could store all that info in something the size of a 'particle'.

Yes, you're right, thats why I said theoretically. As in IF we had a computer that fast THEN would we be able to do it. The computer is not the point, the point is - can everything be predicted if everything is known?

by **Lawrence** » Mar 21st, '07, 20:45

Sir_Digby_Chicken_Ceaser wrote:But its not random as we KNOW that theres more chance of the heavier side landing face down. This immediately cancels out any question of randon .

you're so wrong. trust me dude, I'm doing a maths degree.
probabilities only let you guess at things, you don't KNOW what percentages are going to come out, you can only take a good guess. the outcome is, trust me, random!

by **stepSeven** » Mar 21st, '07, 23:39

New definition of proof: "you're so wrong. trust me dude, I'm doing a maths degree. "

by **magicforfun** » Mar 22nd, '07, 09:51

Lawrence wrote:
Sir_Digby_Chicken_Ceaser wrote:But its not random as we KNOW that theres more chance of the heavier side landing face down. This immediately cancels out any question of randon .

you're so wrong. trust me dude, I'm doing a maths degree.
probabilities only let you guess at things, you don't KNOW what percentages are going to come out, you can only take a good guess. the outcome is, trust me, random!

I have to disagree. The randomness will follow a normal distribution, hence we can predict the outcome with a % deviation. That offsets 100% randomness. It's important to add that every throw off your buttered toast is independent from the result of the former throw. But if you do 1 gazillion throws, you can predict the outcome of these, e.g 52% butter down, 48% butter up or whatever.

Trust me, I did my maths degrees ages ago, but I did'em. :wink:

by **Soren Riis** » Mar 23rd, '07, 10:33

I notice that the discussion continued for some time completely disregarding V. Neumans idea!

Soren Riis wrote:Throwing a coin is fairly random. V.Neuman the inventor of the modern computer came up with a trick that generates random heads and tails even if the coin is not completely fair. Make two throws. If head is followed by tail then the result is head. If tail is followed by head the result is tail. If the two throws leads to the same result disregard the result.

This elaborate procedure reminds me of the following problem.

Problem:
Suppose n people are to divide a bowl of pudding. Find a method that is fair in the sense that if someone gets to little they can only blame them selves!

Solution:
Assume the people is sitting around the table. Lets enumerate them 1,2,...,n.

Person 1 put a portion on a plate. Then person two is asked if he thinks the portion is too large. If he thinks it is, he is allowed to remove any amount of pudding from the plate he might wish. Then its the third persons turn. If he thinks the portion is too large he can remove from he plate any amount of pudding he wish. When all people have had a chance to remove pudding, THE :AST PERSON WHO REMOVED ANY PUDDING gets the plate, and is out of the game. If noone removes any puddling, the first person gets the plate. This procedure is repeated until only two people are left in which case the procedure reduces to the usual "you divide, I choose" game.

Notice that if someone gets too little pudding, they only have themself to blame.

Not quite sure what this has to do with randomness. Ramseys Theorem is a famous theorem in mathematics that in some sense says that true randomness is never possible and that large dataset AFTER WARDS (magicinas choice!!) ALWAYS contains some unusual and surprising patterns! If the data had been slightly different and that pattern had not been present some other pattern would have been there instead.

Ramseys theorem is very good news for magicians, though its hard to apply the principle in practice since the dataset usually needs to be huge and it might take the magician a few hours (if not days) to work out the hidden pattern.

by **Lawrence** » Mar 23rd, '07, 21:02

stepSeven wrote:New definition of proof: "you're so wrong. trust me dude, I'm doing a maths degree. "

i think I'm right, hence my theory is prooved QED! (that was QED factorial for all those maths geeks paying attention out there)

what we do really need, is a proper definition of what is random, since some of us seem to be arguing different definitions!

i'll hunt out my probability books and quote you the axioms for this kind of thing perhaps! (factorial)

by **Tomo** » Mar 23rd, '07, 21:09

Lawrence wrote:what we do really need, is a proper definition of what is random, since some of us seem to be arguing different definitions!

"An event having no dependency to previous events."

How's that?

by **stepSeven** » Mar 23rd, '07, 21:19

Flip a double headed coin, the outcome is random by that definition

by **Tomo** » Mar 23rd, '07, 21:30

stepSeven wrote:Flip a double headed coin, the outcome is random by that definition

In terms of which head comes up, yes. The meaning placed on each side is an artificial, human construct.

by **Lawrence** » Mar 23rd, '07, 21:41

Tomo wrote:
Lawrence wrote:what we do really need, is a proper definition of what is random, since some of us seem to be arguing different definitions!

"An event having no dependency to previous events."

How's that?

seems pretty fair in the terms of coins and dice and whatnot.
but how about for generating a random number? since that's what started all this. although i suppose if you use my "just throw some dice" arguement then that works as a generater by that definition. winner!

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