Solid definition Home › Forums › setting the stage › solids as quantum systems › Solid definition This topic has 0 replies, 1 voice, and was last updated 6 days, 23 hours ago by armasaru. Viewing 1 post (of 1 total) Author Posts January 22, 2026 at 3:34 pm #14448 armasaruParticipant A solid is a piece of matter where particles are held together by strong forces and because of this rigid structure, atoms can only vibrate in fixed positions without moving freely. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In