Comments on: Black Holes Only Grow So Big

By: Syed Moin Doja

Syed Moin Doja — Thu, 06 Nov 2008 14:58:38 +0000

wow nice article, love it when its long and detailed as this one, the longer the better, also you ARE a good teacher – like the way how you handholds us lay people through such difficult concepts and make it appear all so simple – jees how big can a big blackhole get – the thought never even ocoured to me before, really liked the article.

p.s – i check this site regularly, no new post in 16 days, you have us all woried here, hope everything is fine.

thanks

8.28 p.m
Calcutta, India

By: Rob Knop

Rob Knop — Thu, 06 Nov 2008 14:21:42 +0000

Yes, I know I’m a lazy lardass for not reading the paper myself, but at least I admit it….

What about mergers? I *think* I can answer this myself. Once you get up to cD galaxy size, it’d be VERY surprising to have more than a couple of mergers of galaxies over a Hubble time (if that). That is, the cD galaxy is probably eating more moderate galaxies all the time, but those more moderate galaxies will only have 10^6-10^8 solar mass black holes, which will not appreciably add to the mass of the 10^10 solar mass black hole when it inevitably makes its way to the center and joins the monster. cD galaxies themselves are rare enough and spaced out enough that you don’t expect them to merge with each other all that often. I wouldn’t say it would never happen, as clusters come together, but it’s not going to happen more than O(1) times, which means that you’re not going to get appreciably above 10^10 even with those mergers.

That’s my guess, anyway.

By: Wissen ist Macht | F!XMBR

Wissen ist Macht | F!XMBR — Thu, 30 Oct 2008 15:30:02 +0000

[...] Black Holes Only Grow So Big So, in our reality, black holes have an upper limit that comes basically from the fact that things spiral in and the material spiralling in does destructive things: Blasting Light, Blasting Wind. Blame angular momentum and if you want to build a bigger blackhole, get good at aiming stars. [...]

By: Freiddie

Freiddie — Wed, 22 Oct 2008 01:45:32 +0000

“… the gas the SMBH can consum eventually gets pushed away …”

Typo? I think your spellchecker needs to be upgraded.

Still, another informative article on astronomy from Star Stryder. Keep ‘em coming!

By: Colin J

Colin J — Tue, 21 Oct 2008 17:12:32 +0000

And here I was blissfully going about my plans to make a SMBH to rule the universe. On to plan B.

By: Yoo

Yoo — Tue, 21 Oct 2008 08:52:41 +0000

But, but, supermassive black holes will still grow as they absorb the cosmic microwave background!

(Doubt that the CMB actually contributes significant mass to an SMBH, but even if it did, I have a sneaking suspicion that the steady weakening of the CMB due to the universe’s expansion would still give an upper limit to the mass of almost all SMBHs.)