So the cake is a slice of cake, a whole cake, and a cake with a slice taken out,  
All at the same time

the cake is an exaggeration

@Nightweaver20xx  
Until you observe the cake, yes.

@Nightweaver20xx  
So the cake isn’t a lie, it’s more of a fib?

@Nittany Discord  
So… it both is and isn’t there at the same time?

We learned Copenhagen Interpretation in school because it was easier to teach. I can say looking at the mathematics does make QM easier to understand since a lot of these conclusions come from math. For example, this cake is just demonstrating quantum superposition, which is the sum of all nonzero wavefunctions of the cake.

@Registered Anon  
Oh, yeah, so in case you didn’t catch it, be aware that that poster is probably kinda nutty. I don’t think he actually made that video, so much as uploaded someone else’s as his own. Ugh.
 
See: @Stardust-Wayfinder
 
It’s probably another case of people misunderstanding quantum mechanics to construe some sort of spiritualism out of it. It can happen very easily when you know a certain amount, but not a whole lot, thus the phrase; “Sophomore” exists, meaning “wise fool.”
 
“A little learning is a dang’rous thing;/Drink deep, or taste not the Pierian spring.” (Source)
 
When the video says “observer,” there’s two things to note:  

@Registered Anon  
True that.

@Nittany Discord  
The more precisely one is known, the less precise the other has to be. It’s one or the other that has to be more precise. I’d prefer the former to be more precisely measured in this case.

Let’s hope you can measure deliciousness and calories exactly. No general uncertainty principle to worry about.

@Registered Anon  
However, it has about 467,466 calories.

Either zero calories or enough calories to feed an African village for a week!

@Stardust-Wayfinder  
Lol, well, thanks for noticing and putting the warning sign up. That’s pretty ridiculous.

@Cirrus Light
 
Decent explanation of the experiment. But the source of that animation, “What The Bleep Do We Know?” is utter horseapples. Considering the founder of the organization that made it claims to be the reincarnation of an ancient Mesopotamian spirit. :p

@Stardust-Wayfinder  
Interesting.

@Registered Anon  
It means quantum weirdness.

@Stardust-Wayfinder  
It’s like a big blue wave.

@Registered Anon
 
https://en.wikipedia.org/wiki/Double-slit_experiment

The wave and particle decorations. :p

@Keith Mowz  

@Keith Mowz  
Didn’t notice that. I don’t actually know what it means.

I know just enough about quantum mechanics to get a laugh out of the knife with double slits.

@Registered Anon  
An object with one planck mass and one planck distance in diameter would collapse into a black hole by GR. Not that GR is really valid at those distances, though :p
 
 
@Nightweaver20xx  
Of course! What else would the quantum knife be for?

@Nightweaver20xx  
There will be until you look at it.

@Registered Anon  
Sooo… will there be cake or won’t there be?