That’s just not true, it’s an artifact of the Bohr model of the atom which doesn’t take the wave-particle duality of the electron into account. The wavefunction of the electron is “smeared” around the atom, which is not empty.
The black hole as dark matter theory is also largely discredited (MACHO theory for MAssive Compact Halo Object) because gravitational lensing studies don’t support it.
The black hole as dark matter theory is also largely discredited (MACHO theory for MAssive Compact Halo Object) because gravitational lensing studies don’t support it.