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Russian doesn't care if he solved $1M Math problem

 
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Russian may have solved $1M Math problem

He don't care if he has.

"There is good reason to believe that Perelman's approach is correct. But the trouble is, he won't talk to anybody about it and has shown no interest in the money," said Keith Devlin, Professor of Mathematics at Stanford University in California.

"There won't be a golden moment when he is suddenly accepted as being right. There will just be a drift in that direction," he told the annual meeting of the British Association for the Advancement of Science.

More on Wikipaedia.

Grigori 'Grisha' Yakovlevich Perelman

If he'd give it away in a lottery people mught think about Maths more often.
[ September 07, 2004: Message edited by: Helen Thomas ]
 
Helen Thomas
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The Math behind Perfect Parallel Parking.

Slide Rules

To help determine when the car has gone far enough forwards or backwards and NOT when the car on either side starts shaking because you've collided into it. This kind of MAth deserves a $1M prize.
 
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It seems to be empirical formula,right.Must have experimented a lot.Interesting.
P = r - w/2
G ≥ w + 2r + b
F ≤ w + 2r - fg
For the perfect park, those formulas must satisfy the following relationship:
Max ((r + w/2)2 + f2, (r + w/2)2 + b2) ≤ min (4r2, (r + w/2 + k)2)
Definitions:
Position (P) = Where to set up for the parallel park
Gap (G) = Determines if parking gap is large enough
Front of car (F) = Determines where front of car should go
r = turning radius of your car
w = width of your car
b = distance from back of car to point midway between axles
fg = gap you want left at the end
k = distance from curb where you end up
Now P is a position,but which is the origin?
 
Helen Thomas
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Er, I haven't tried it out. I think the lady fails to mention speed. It's not often you see parking below 25mph.See a space, nab it before someone else does. I'm sure speed has an effect on all the other factors.

Schrodinger's thought problem :

A cat is to be sealed up in a box in which there's a decaying atom, a device to measure the decay and a relay so that if an atom decayed, a poisonous gas would be released that would kill the cat. Since no one could predict when the particle would decay, the life span of the cat was indefinite but it could be discussed as a probability. Mathematically, the situation would be expressed as the cat being both living and not living to a certain extent, but as we all know, for the most part, that is a condition that is very difficult to achieve. So empirically, the cat would either be alive or dead.

This problem is to do with quantum physics. Now why does the cat have to be killed ? Can't the problem be expressed without the cat?
 
Helen Thomas
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It gets worse for Schrodinger's cat.

"First, we have a living cat and place it in a thick lead box. At this stage, there is no question that the cat is alive. We then throw in a vial of cyanide and seal the box. We do not know if the cat is alive or if it has broken the cyanide capsule and died. Since we do not know, the cat is both dead and alive, according to quantum law, in a superposition of states. It is only when we break open the box and learn the condition of the cat that the superposition is lost, and the cat becomes one or the other (dead or alive).

Schrodinger himself said, later in life, that he wished he had never met that cat."

The wee quantum furrball is a theoretically observable and measurable reality but the problem is only interested in probabilities.
[ September 07, 2004: Message edited by: Helen Thomas ]
 
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Originally posted by Helen Thomas:
It gets worse for Schrodinger's cat.
"First, we have a living cat and place it in a thick lead box. At this stage, there is no question that the cat is alive. We then throw in a vial of cyanide and seal the box. We do not know if the cat is alive or if it has broken the cyanide capsule and died. Since we do not know, the cat is both dead and alive, according to quantum law, in a superposition of states. It is only when we break open the box and learn the condition of the cat that the superposition is lost, and the cat becomes one or the other (dead or alive).



Has anyone read Endymion by Dan Simmons? Its a book set in the future. In that book a guy is sentenced to death, but no one wants to have to execute him. Instead they put him in a large version of Schrodinger's cat box (the one with the cyanide being released by a particle decaying), so that its down to "fate" as to when he dies. He's then stuck in a box that is the size of a prison cell, just waiting for the poison to come, not knowing when it will.
 
Joe King
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Originally posted by Arjun Shastry:
It seems to be empirical formula,right.Must have experimented a lot.Interesting.
P = r - w/2
G ≥ w + 2r + b
F ≤ w + 2r - fg
For the perfect park, those formulas must satisfy the following relationship:
Max ((r + w/2)2 + f2, (r + w/2)2 + b2) ≤ min (4r2, (r + w/2 + k)2)
Definitions:
Position (P) = Where to set up for the parallel park
Gap (G) = Determines if parking gap is large enough
Front of car (F) = Determines where front of car should go
r = turning radius of your car
w = width of your car
b = distance from back of car to point midway between axles
fg = gap you want left at the end
k = distance from curb where you end up
Now P is a position,but which is the origin?



I read an interesting article somewhere about the differences between male and female parking. Apparently men tend to have a better spatial awareness then women, so generally find parking easier. Unfortunately this is counter-balanced by a larger tendency to be aggressive. The average man should therefore be less likely to park badly because of this spatial awareness, but is actually more likely to crash while parking aggressively.
 
Arjun Shastry
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Then I think in next version she might refine the formula,may be like
G ≥ w + 2r + b+f(k) if driver is female
G ≥ w + 2r + b-f(k) if driver is male
where f(x)is some function.
[ September 08, 2004: Message edited by: Arjun Shastry ]
 
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