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katastrofa
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Celebrating this year's Abel Prize with a brainteaser

March 19th, 2021, 12:43 am

I think I saw "Where's Wally?" game for the first time in my life in this forum. Let's complicate it.

You want to prove someone that you know where Wally is in the picture, but you don't want them to be able to find Wally themselves. How can it be done?

Hint: Abel Prize was awarded to Avi Wigderson and Laszlo Lovasz
 
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Paul
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Re: Celebrating this year's Abel Prize with a brainteaser

March 19th, 2021, 1:06 am

Get it notarized?
 
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bearish
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Re: Celebrating this year's Abel Prize with a brainteaser

March 19th, 2021, 1:22 am

Sell them an NFT?
 
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Alan
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Re: Celebrating this year's Abel Prize with a brainteaser

March 19th, 2021, 3:07 pm

Excellent question! I learned a lot looking it up. Anyway, I learned the the answer is: position the picture behind a very large cardboard, cut out just to show Waldo. When the cardboard is much larger than the picture with Waldo, you don't get a fix on his position. Luckily, I have such a piece of cardboard:  :D
Waldo.JPG

 
 
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katastrofa
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Joined: August 16th, 2007, 5:36 am
Location: Alpha Centauri

Re: Celebrating this year's Abel Prize with a brainteaser

March 21st, 2021, 6:49 pm

All interesting answers! Alan's zero-knowledge proof, even if the most topical, possibly not practical? - too easy to cheat when the check is so narrow. Like a cheating husband going for a fake business trip.
 
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bearish
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Re: Celebrating this year's Abel Prize with a brainteaser

March 21st, 2021, 9:00 pm

I remember business trips. Some were fun, others mostly tedious. As far as covers for cheating goes, I’m thinking genuine ones are a lot more robust than fakes. Not to mention the benefit of having somebody else pick up the tab. This is of course merely a hypothesis on my part.