If I wanted to post about optics and laser experiments, what forum would I do that in?
You'd have been better off just posting your question, because this isn't the "ask which forum to post in" forum, so this way you're guaranteed to break the rule.
Yeah, this forum is just fine to start off with. Should the specifics or eventual discussion potend to something more applicable in another forum, the Moderators will move it accordingly.
So, post away!!
If you're looking for help with solving a specific homework or classwork exercise, then it goes into one of the "Homework and Coursework Help" forums, generally Introductory Physics if it's for a first-year course, or Advanced Physics if it's for an upper-level course.
Otherwise, for asking about concepts etc.:
If it's geometrical optics (ray diagrams, thin-lens equation, etc.) or wave optics (diffraction, interference), it's classical physics and goes in the classical physics forum. Experiments that use lasers just as light sources for classical interference experiments etc. would go there.
If it's about light as photons, or the quantum mechanics of how a laser or other similar light source works, it's quantum physics and belongs in the quantum physics forum.
If you can't make up your mind whether an experiment is more "classical" or "quantum", just pick one place or the other, and we'll move the thread if we think it's appropriate.
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