That's indeed a layman explanation of the mainstream theory. From what I understand of this theory (not a physicist), particle are not small atomic objects but

That's indeed a layman explanation of the mainstream theory. From what I understand of this theory (not a physicist), particle are not small atomic objects but they're not waves either. Nobody can describe what they are otherwise than by mathematic equations describing their interaction. Some of these equations describe some aspects of reality accurately if you think of particles as objects, some others describe some other aspects of reality well if you think of particles as wave. Doesn't mean that particles are either, they just behave like one or the other depending what you're studying