This question already has an answer here:
I'm sure variations on this come up a lot, but I was specifically interested in a response to a claim made by a particular article:
The article is aiming to disprove the idea that an 'observer' collapsing a wave function has anything to do with consciousness or human observers.
At one point it argues that the reason an electron in the double slit experiment has its wave function collapsed when detected before entering one slit or the other is due to the photons fired at it to detect its position having momentum and physically interacting with it. The author uses the analogy of tennis balls being fired into a dark room and using a tennis racquet to detect them - the method of detection causes a change in their behaviour.
Now in this instance that's all well and good, but firing photons is not the only means of detecting something. In the Schrödinger's cat thought experiment, for instance, a Geiger counter is used. As far as I understand it, these simply detect passively rather than firing out photons with momentum.
I know many people disagree with the wave function collapse theory and prefer decoherence (which I'm still wrapping my head around) but I'm interested to know if this is something that's explained within collapse theory or if it's something that's seen as disproving it.