I have a question that may seem kind of simple, but I would like to hear your thoughts about it. Is there such a thing as a fundamental particle of which all other particles are made of, or even if is even possible for such a thing to actually exist? A particle of continuous matter (no empty spaces inside) , what density would it have? The reasons for this question are many. For example, if an atom has the size of a stadium its nucleus has the size of a pea, so what before could have been consider as the smallest block of matter is actually almost empty space with all its matter in a comparatively tiny size of its space, and then subatomic particles were discovered. Are they too made up of even smaller particles? And if no such fundamental particle actually exists, then what is the true nature of matter?