After all, two light beams can be at the same place at the same time, or a light beam and a window. When you try to put many of these particles of the same type in the same region of space, their avoidance of each other produces a degeneracy pressure . Degeneracy pressure is much higher for electrons than it is for protons or neutrons. It is very hard to pack electrons into a small space. Answer - You have a lot of electrons, and degeneracy pressure preventing you from entering a wall is enormous.
Degeneracy pressure can be extremely strong.
Degeneracy pressure doesn't care about temperature. If I cool you off, it still isn't easy to push you into the wall. White Dwarfs White Dwarfs are stars that have no more Helium left to burn. They are a balance of Gravity versus degeneracy pressure. Temperature is irrelevant.