Physics says you can eat your cake and still have it

Can you eat your cake and still have it?

I know all of you, cakephilias 🤣, will love to have all those cakes you've eaten back. Well, if you're ready to do some Quantum Physics, you wish might just come into pass.

Explaining this by my big brother, another young promising scientist, he said:

"One of the strongest laws in Quantum Mechanics is Unitarity.  Which explicitly and strongly states that information cannot be destroyed.

Therefore, in the event that you eat your cake, the information that defines that cake is preserved.

BUT THE CAKE HAS BEEN EATEN AND GONE...
Yes, this is a different situation. Local destruction or change doesn't mean that the information is gone. The information must still exist in the system.

So you could in principle burn your certificate and get it back. But quantum mechanics will beg you to wait for longer than the lifetime of the universe"

However, I explained the concept using the concept of Quantum Superposition in which "the cake can either be eaten and still have it", if and only if, you're in a quantum system such that the two possible states - cake is eaten and still have it - are superimposed

But I posed the argument that Superposition and Unitarity are the same thing but slightly different in context. So what is the difference...?

It's simple....
If you consider Superposition, the moment you observe a possible states, for instance you eat the cake, you're already in a classical system in which you cannot get the cake back. In other words, you cannot go back in time to get your cake even after you've eaten it...

However, considering Unitarity, it represents the two states as an information in which, if you can easily go back in time to get the cake back even after you've eaten it....