A Planck mass (assuming h-bar and not h is used as Planck's constant - an arbitrary choice), is 22 micrograms. Not that small, on a particle scale. I mean, unlike the Planck length, which happens to be quite small, other Planck units are not dazzlingly evocative of quantum woo woo weirdness - something the Planck length enthusiasts don't really talk about much, but I digress.

It would take an astronomical number of them to account for the mass in the galaxies that we cannot see, but whose effects we can see.

What is the proposed mechanism that prevents Hawking radiation from evaporating this micro black hole?

If there are naked singularities in the universe, they are almost certainly quite rare. The mechanisms by which a black hole can shed its event horizon require it to somehow acquire angular momentum at a rate great enough to compensate for its increasing mass. There isn't a single known observation of a naked singularity, and if they exist, they are lost in the uncertainty of the data. Which means that if they are *there*, their effect on the universe we see is not a dominant factor in the universe's structure. I.e. for any proposed naked singularity that is consistent with GR, we can rule out that those are the dark matter that we see the effects of, but not the cause of.


What says that a naked singularity will not interact with light at all.. i.e. be dark - a signature requirement of dark matter?



My gut says, if they are possible in the theory of GR, and the vastness of the universe is what it is, then they're out there somewhere.