Schneider's cat works by quantum theory of superposition, and interpretations of quantum mechanics have been proposed. There for showing you the use of Schneider's cat work.

Superposition of Waves: Linear Homogenous equations and the Superposition principal nonlinear superposition and consequences.

The superposition theory is a theory in quantum mechanics that states that an object (that is microscopic or unaffected by coherence i.e. behaves in a way predicted by quantum mechanics) can be in more than one place at the same time. This arises partially from the uncertainty principle but also how waves behave. A easy way to imagine this is if you have too unopened boxes, one has an object in the other doesn't however you do not know which box has the object so in Quantum Mechanics this would be a superposition state - the object - because it is unmeasured is in both boxes at the same time. Now to describe how this superposition state "collapses" into the object being in only one box you have to describe or show the objects as waveforms - basically graphs describing the probability of finding the object in a certain position. In our box scenario the object will have two wave forms - as it is in a superposition state - one describing it as being in the left box and the other as the right but how these waveforms "collapse" into one is still up for debate the most famous being the Copenhagen Interpretation and the other the Many Worlds theory but that is for further reading.

Hope I helped!

A coherent state is a quantum state that is a superposition of different number states. It represents a well-defined classical-like state of an oscillator in quantum mechanics, with a fixed phase relationship among different energy levels and minimum uncertainty in position and momentum measurements. These states are important in quantum optics and quantum information processing due to their special properties.