[ExI] Spaceflight: The only valid case for waiting

[Anton Sherwood]

On 2020-9-28 18:46, spike jones via extropy-chat wrote:
> Ja, and of all cool things: a notion I have had for a long time is that 
> the dark matter (or some of it) may be small-ish black holes that formed 
> very early in history, a few hundred thousand years after the big bang.  
> I do confess I don’t understand how that can happen, but if I suggest 
> that they just did somehow form, very early then they would be far 
> enough back there to account for what still looks to me like missing 
> matter.  If they were small-ish black holes and we ignore for now that 
> we can’t explain how those formed, then they wouldn’t be big lensers and 
> wouldn’t even be easily detectable.  I hear that theory is enjoying a 
> revival.  Cool!

Larry Niven's story "The Borderlands of Sol" supposes that the Tunguska 
object was a primordial black hole, formed in the turbulence of the Big 
Bang.

But last I heard, it's believed that such tiny BH, if they existed, 
evaporated by Hawking radiation long ago.

-- 
*\\*  Anton Sherwood  *\\*  www.bendwavy.org