There is a discussion about whether there is an absolute maximum density for substances, with black holes cited as examples of objects with maximal density relative to their size. It is noted that adding energy to a black hole causes it to grow, resulting in larger black holes having lower density. The conversation also touches on the minimum distance between particles, suggesting that this distance influences density considerations. Below the Planck length and above the Planck density, meaningful statements about density become problematic. Overall, the topic explores the limits of density in physical systems.
