Serving the Quantitative Finance Community

 
User avatar
katastrofa
Topic Author
Posts: 7440
Joined: August 16th, 2007, 5:36 am
Location: Alpha Centauri

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
 
User avatar
Paul
Posts: 6604
Joined: July 20th, 2001, 3:28 pm

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

March 19th, 2021, 1:06 am

Get it notarized?
 
User avatar
bearish
Posts: 5188
Joined: February 3rd, 2011, 2:19 pm

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

March 19th, 2021, 1:22 am

Sell them an NFT?
 
User avatar
Alan
Posts: 2958
Joined: December 19th, 2001, 4:01 am
Location: California
Contact:

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

 
 
User avatar
katastrofa
Topic Author
Posts: 7440
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.
 
User avatar
bearish
Posts: 5188
Joined: February 3rd, 2011, 2:19 pm

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.