Hi all, I was wondering if anyone is aware of any theories in physics that don't rest on the assumption that matter exists. I've heard a few theorists (both particle physicists, string theorists, and mathematicians) describe how it becomes very hard (if not impossible) to describe what an object or a particle really is once you zoom in enough. In other words, the question of whether fundamental particles really exists can become somewhat meaningless as math becomes the only language that correctly describes reality at that level. Could it be that the universe only consists of energy? And that matter is thus an illusion? I'm sure someone must have theorized about this. Any thoughts? Thanks!