Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Primordial Black Holes

  • Please log in to reply
6 replies to this topic

#1 Elijah8383939

Elijah8383939

    Lift Off

  • -----
  • topic starter
  • Posts: 2
  • Joined: 01 Dec 2019

Posted 01 December 2019 - 07:24 PM

Hey, do any of you guys know if Primordial black holes actually exist?



#2 Barlowbill

Barlowbill

    Viking 1

  • *****
  • Posts: 643
  • Joined: 05 Apr 2018
  • Loc: Tulsa, Oklahoma

Posted 01 December 2019 - 07:38 PM

Wikipedia says they are hypothetical so they must be so



#3 TOMDEY

TOMDEY

    Fly Me to the Moon

  • *****
  • Posts: 5,699
  • Joined: 10 Feb 2014
  • Loc: Springwater, NY

Posted 01 December 2019 - 09:13 PM

Hey, do any of you guys know if Primordial black holes actually exist?

Hi, Elijah! Primordial, as in nearly as old as the Universe?

 

Well, the one relatively simple thing we know about all black holes is that the length of time it takes them to evaporate, in the absence of additional infalling material, is a monotonically, continuously differentiable increasing function of their mass. That would put an abrupt lower initial-mass bound on primordials... even though their current mass could be arbitrarily small. One would then have to run that through the mass-density history of the universe and modeling of probable sources of incoming, to determine "how many" primordials likely remain. That number would be somewhere between "probably none" to "probably lotsa" and would include statistics on the mass vs number distribution.

 

I'm sure theorists are working on that --- and may still be unsure whether there are probably none or most certainly many.

 

What is probable... is that no one here knows whether primordial black holes actually exist. Both we and the professionals would be at the speculation phase of discovery. And even if candidates are found... to prove that any are indeed primordial, rather than recent genesis... would be the next big hurdle.    Tom



#4 Jim Davis

Jim Davis

    Skylab

  • *****
  • Posts: 4,151
  • Joined: 05 Jul 2014
  • Loc: Lewisberry, PA

Posted 01 December 2019 - 09:15 PM

None have ever been spotted.


  • jim kuhns likes this

#5 Tony Flanders

Tony Flanders

    Hubble

  • *****
  • Posts: 17,416
  • Joined: 18 May 2006
  • Loc: Cambridge, MA, USA

Posted 02 December 2019 - 01:26 PM

My impression is that some theories predict that primordial black holes may exist, but there's no solid evidence to back that up.


  • jim kuhns likes this

#6 Rich (RLTYS)

Rich (RLTYS)

    Fly Me to the Moon

  • *****
  • Posts: 7,001
  • Joined: 18 Dec 2004
  • Loc: Mayo (Maryland)

Posted 03 December 2019 - 08:14 AM

Who knows? But it'll be great to eventually find out.



#7 Elijah8383939

Elijah8383939

    Lift Off

  • -----
  • topic starter
  • Posts: 2
  • Joined: 01 Dec 2019

Posted 04 December 2019 - 02:14 PM

Thank you so much for your responses.  I asked this question for a school assignment where we had to ask astronomers, questions, that we couldn't look up.  I used your responses and shared them with my class.  




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics