'Stupendously large' black holes could grow to truly monstrous s

This was a fun read. A black hole with 100E+9 solar masses, the Schwarzschild radius ~ 2.95E+11 km, diameter ~ 3948 AU. Sgr A* reported at 4.5E+6 solar masses. Schwarzschild radius ~ 1.3E+7 km, diameter ~ 0.18 AU. Should be even more fun if any BH this size are discovered and reported :)
I suspect there is an upper limit to size within a universe. It will crunch and bloat to the point where it has "holed" so much it will itself fall into it and close up the hole behind it. The infinite of crunch is the Big Crunch and every wormhole of a blackhole points, leads, to it. One should always remember that it is not only a matter of mass-energy but also a matter of space-time. Or is it elastically contracting mass-space and expanding time-energy? In any case there should be a limit to its weight in point in the universe (before the particular [finite] universe simply drops it out, zeroes it out), a limit to its distortion of space-time before the wrap wraps to the point of snapping shut on itself (reaching the point where it becomes its own worst enemy, its own nemesis).

It's not going to reach hyper-dimensionality, hyper-finite, or infinity, up or down, in or out, because such is already taken care of by the Universe. The most it could do is merge, and that is what I said above. So, it will have a limit. We just don't exactly what that limit is, yet. After all, size is a relative notion.
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Nov 29, 2020
I suspect there is an upper limit to size within a universe. ...

It's not going to reach hyper-dimensionality, hyper-finite, or infinity, up or down, in or out, ... So, it will have a limit. ,..,.

So you conclude there is an upper limit because you suspect, and then say, there is one. Not very convincing. I suspect there's a limit, but it will be reached when all the material close enough to be sucked in is sucked in. There might be a SLAB at the center of some of those gargantuan voids where currently we detect nothing at all.

Even so, after several quadrillion years, the universe might degenerate into SLABs slowly closing the distances between themselves and merging into SuperSLABs, then SuperMassiveSLABs, then UltraMassiveSLABS. It will be convenient for any creatures observing to already have handy the nomenclature for these bad boys.

10-15 years ago I read in one of these popular science mags that there is a natural upper limit on black holes of 2 billion solar masses. There was a rationale but I don't recall it, meaning it didn't persuade me. In his short book about black holes back in 1977, Isaac Asimov speculated that the universe itself is a black hole. You know, finite but unbounded. Fun stuff to think about.
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Jan 23, 2021
you also have to consider the possibility of a supper massive black hole being able to grow to that proportion of size.
Our galaxy currently contains the largest black hole discovered throughout the universe, what if TON 618 were to grow to those proportions or even bigger? If it could, id believe it would have devastating effect all throughout the Milky Way galaxy, along with the possibility of effecting the gravitational pull that the Milky Way and the Andromeda galaxies have on each other, dont you think so too?
Mar 5, 2020
Tall tales around the campfire.

There is a giant something out there behind that bush!

No matter what the angle of view or how close black holes are supposed to be we don’t ever have a clear image of them.

Yet the scientific orthodoxy considers it heresy to suggest that black holes don’t actually exist.

So much for evidence based science.