I know my question is so simple to ask but I'm new in this subject.
I'm studying energy systems engineering in university and I took physics and advanced physics but I never truly understand how photons have no mass but they're carrying energy. How is it possible ?
I thought photons are some kind of pure energy but I saw NASA made solar sails to create propulsion, how can you create propulsion without exhaust mass ? (Momentum equation collisions)
Also how can we "create" photons ? Like you can convert something into something else but creating must be impossible.
I read about double slit experiment and it confused me even more and it gets more and more complicated the deeper I go.
I'm sorry if my lack of knowledge or English making my question hard to understand & read