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The scientist who find the point where super position stops will get the Nobel price for sure, I could give you a hint, it is less than my cat, I'm sure it never been in two places at once (Schrödinger is right about his cat too)

Superposition is not stopping as far as we know it.

Cat typically weighs 3,6 – 4,5 kg. De Broglie Wavelength of 4 kg cat moving 1×10^-10 m/s is 1.7×10^14 m.

You cat is in many places at once, those places are just very close to each other.

Something I don't quite understand about quantum mechanics and the MWI... At the point the atom passes through the diffraction grating, it has a quantum superposition. According to MWI, reality has "branched", right?

Then the two realities interfere with each other to form the probabilistic pattern at the detector. So, according to MWI, reality has "merged" again?

If we accept the mulitiverse idea of MWI, doesn't that mean at some point particles aren't able to marge with their branched-reality versions?

The "at some point" doesn't have to do with time. It has to do with the rest of the wavefunction of the universe. If the atom becomes entangled with everything else (in fact, a single quantum-mechanical spin suffices) the two branches become orthogonal and the interference terms from 'merging' vanish. We say the wavefunction 'decohered' when it becomes too complicated to see how to reverse this effect---as more and more particles get involved it becomes hopeless.

That exponent for the wavelength is wrong. It should be more like 1.6x10^-33m. At least it should be negative.

Yes. it should be 1.7×10^-14 m.

Our cat is often in many places at once. He's able to remain in superposition between the garden, the sofa and our bed until I open the fridge, whereupon his wave-function collapses and he's instantly in the kitchen without moving through the intervening space.

Or maybe the odds of your cat being in two places at once is miniscule and is less and less likely the more lasagna he or she eats.

Or your cat is always in all places but your experience only one. At least that one of you.

In any case, the cat is the boss in all instances. My cat is very disappointed in me right now that I can't stop the onset of winter and demonstrates it very effectively!

There is probably some space-time position where he is completely content but I think that's rarer than seeing him in two places at once.

I'm off shooting cats through two slits I made in my living room wall now, to prove or disprove you. For Science!

The result of which is more Jackson Pollock than interference pattern...

Always wondered about the backstory for Bill the Cat.

I always wondered about Fritz the Cat...


Superposition doesn't stop, or that at least is what I understand. The uncertainty principle can be expressed in terms of increments of energy and increments of time: the farer I could be from where I am supposed to be, so to say (that is the energy increment) is inversely proportional to the time that can be measured (that is the time increment).

However, given that I'm no expert on the topic, I wish someone in a better position could elaborate on this idea.

> it is less than my cat...

Wouldn't it be ironic if decades of misdirected science could have been avoided if Schrodinger put his hamster in the box.

My guess is that if the object can record for itself which slit it went through, the effect would stop.

could it be down to the speed of light and distance between both apparent positions of the particle?

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