I don't know how this works...but it does!

The pythagorean theorem, i would guess after a quick glance

 

Its the same as what happened to Wildchild, he pivoted too many times and his brain fell out the hole.

 

Thanks, that explains everything.

 

It's because he's not putting the card through the hole. He's holding the card behind the piece of paper. It's called sleight of hand.

 

I don’t think so.

 

You are definitely gullible. Don't play 3-card monte with any street peeps in Vegas, you won't fare well.

The guy even says in the vid it was showed to him by a magician.

 

I don’t think so. While he likes magic, he’s a scientist at McGill University. His reputation is very much that of a straight shooter in these here parts. It would be very uncharacteristic of him to try to pass off a simple trick as something else. I could be wrong, but I don’t think so.

 

It is a trick but not sleight of hand. The "square" in the middle is not square but instead a rhombus where the horizontal diagonal in video is large enough for the card to fit through, but the vertical diagonal isn't.


It looks like a square, but it's more like


It's easier to see when the card is closer to the paper.

 

I dunno, doesn't look like a rhombus from this angle...