What do "pervading" and "aether" mean? What do "pervading" and "aether" mean in: "Isaac Newton considered light to be a beam of particles that set the pervading aether vibrating." ? I'm not taking a Quantum Mechanics course but I might in the future but either way, I'm interested in learning about it so I bought this book and that's the very first sentence and I already don't get it lol. Could someone please break this down so I can understand it? Thanks in advance!