Earlier quoted context omitted.
> No, that's not what superposition means a priori. The word was originally used to describe the decomposition of waveforms into sums of sinusoids, which is as canonical an example of a linear system as you can get. > the idea of a system being in "two states at the same time", apart from vector addition. But that's not what's going on. A system is only ever in one state at a time: the ability to treat it as a sum (m…
> > No, that's not what superposition means a priori. > The word was originally used to describe the decomposition of waveforms into sums of sinusoids, which is as canonical an example of a linear system as you can get. You are right, I was being a bit too sloppy with my usage of the term "superposition". I guess once people realized that a QM system being in "two states at the same time" is just a linear sum like fo…
Re: The tensor product, demystified (2018)
#31A useful illustration: polarized light can be considered to be in a superposition if you use a basis rotated 45 degrees to the polarization axis. So whether or not polarized light is in a superposition depends entirely on how you choose to look at it. It's not a reflection of the underlying physical reality.