As another commenter has noted, they wouldn't then be galaxies. And the question of whether there are (or how common and at what mass) galaxyless dark matter overdensities (think of it as a clump, in the literature they…
As another commenter has noted, they wouldn't then be galaxies. And the question of whether there are (or how common and at what mass) galaxyless dark matter overdensities (think of it as a clump, in the literature they…