New theory about the first black holes: 10 million Solar mass stars!

Sounds like they're saying that the original stars may have been so
massive that once their hydrogen cores ran out of hydrogen, they simply
contracted straight to black holes. That is, there wasn't enough energy
left to be extracted from subsequent helium fusion to keep their cores
inflated, like we see with modern stars.

This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

Yousuf Khan

SPACE.com -- Monster Black Holes May Grow in Giant Star Cocoons
"The biggest black holes in the universe are also the most perplexing.
Scientists have long been confused about just how the earliest, most
massive black holes formed, but new evidence now suggests they could
have originated inside giant cocoon-like stars.

This idea is at odds with the prevailing thinking that large black holes
are created by the clumping together of smaller black holes.

Not so, says University of Colorado at Boulder astrophysicist Mitchell
Begelman. Rather, these behemoth black holes likely formed in the middle
of even larger supermassive stars that could have held tens of millions
of times the mass of our sun, according to Begelman. "
http://www.space.com/scienceastronom...le-cocoon.html

On Dec 8, 10:27*am, Yousuf Khan wrote:
Sounds like they're saying that the original stars may have been so
massive that once their hydrogen cores ran out of hydrogen, they simply
contracted straight to black holes. That is, there wasn't enough energy
left to be extracted from subsequent helium fusion to keep their cores
inflated, like we see with modern stars.

This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

* * * * Yousuf Khan

SPACE.com -- Monster Black Holes May Grow in Giant Star Cocoons
"The biggest black holes in the universe are also the most perplexing.
Scientists have long been confused about just how the earliest, most
massive black holes formed, but new evidence now suggests they could
have originated inside giant cocoon-like stars.

This idea is at odds with the prevailing thinking that large black holes
are created by the clumping together of smaller black holes.

Not so, says University of Colorado at Boulder astrophysicist Mitchell
Begelman. Rather, these behemoth black holes likely formed in the middle
of even larger supermassive stars that could have held tens of millions
of times the mass of our sun, according to Begelman. "http://www.space.com/scienceastronomy/091208-st-black-hole-cocoon.html

I want to get paid for pure conjecture!
Could've, would've, should've.

john

is it possible that black holes in the universe disturb the planet earth

john wrote:

[...]

I want to get paid for pure conjecture!
Could've, would've, should've.

john

Learn the difference between 'wild assed guess' and 'educated conjecture'.

RUFUS PATTERSON wrote:
is it possible that black holes in the universe disturb the planet earth

At the most pedantic level, every object in the universe disturbs every
other object through their gravity. At a more pragmatic level, no.

Yousuf Khan

On Dec 8, 8:27*am, Yousuf Khan wrote:
Sounds like they're saying that the original stars may have been so
massive that once their hydrogen cores ran out of hydrogen, they simply
contracted straight to black holes.

What gets my attention is the idea that they did so without blowing
off their outer layers!

That is, there wasn't enough energy
left to be extracted from subsequent helium fusion to keep their cores
inflated, like we see with modern stars.

Or maybe whatever process allowed them to collapse quietly without
blowing off the so-called cocoon is "poisoned" by the presence of
heavy elements that didn't yet exist when these stars formed.

Something to do with turbulence, maybe?

More likely there was plenty of energy, but it just wasn't available
fast enough. That is, as the core collapses the helium _will_ fuse,
and so will the products thereof, but the collapse is going too fast
for the released energy to counter, and at the end the black hole is
swallowing freshly-minted iron and transuranics.

What I have trouble with is the idea that the outer layers stayed
around rather than wandering off. A huge accretion disc seems more
reasonable but that isn't mentioned in the article.

This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

Just goes to show, we don't know everything.


Mark L. Fergerson

wrote:
On Dec 8, 8:27 am, Yousuf Khan wrote:
Sounds like they're saying that the original stars may have been so
massive that once their hydrogen cores ran out of hydrogen, they simply
contracted straight to black holes.

What gets my attention is the idea that they did so without blowing
off their outer layers!

Well, it's likely that these potential stars formed in a universe far
more compact than the one we're in now. So there simply may not have
been enough time or space for the excess gas to go very far.

Also the very mass of this gas sounds like each star would occupy a huge
amount of volume by itself, possibly light-years. Each star would have
diameters light-years across! So it would take solar winds, even coming
from the closest reaches of the core, years to reach the outer shell.
Also since the speed of solar winds would be less than the speed of
light, it's possible that solar winds simply couldn't escape from the
core, because the escape velocity was just too high. Perhaps the escape
velocity of these stars was just barely under the speed of light, thus
preventing them from becoming black holes right from the start.

That is, there wasn't enough energy
left to be extracted from subsequent helium fusion to keep their cores
inflated, like we see with modern stars.

Or maybe whatever process allowed them to collapse quietly without
blowing off the so-called cocoon is "poisoned" by the presence of
heavy elements that didn't yet exist when these stars formed.

Something to do with turbulence, maybe?

If you take gas, at the same density as Earth's atmosphere at sea level,
and just fill it in a sphere the diameter of Earth's Solar System, it
will be a supermassive galactic black hole. That's not an unimaginable
level of density, yet it's got mass sufficient to stop light from
escaping. So I would imagine these old stars might not have been all
that dense, but could still start nuclear fusion.

More likely there was plenty of energy, but it just wasn't available
fast enough. That is, as the core collapses the helium _will_ fuse,
and so will the products thereof, but the collapse is going too fast
for the released energy to counter, and at the end the black hole is
swallowing freshly-minted iron and transuranics.

Fusion process happens on the nanosecond scales. It would seem unlikely
that an irreversible collapse would happen before helium fusion could
begin. It's more likely that the helium fusion didn't produce enough
energy to stop the collapse, than it was that it didn't start quickly
enough. Hydrogen fusion is the most exothermic of all of the fusions.

Perhaps we were a little imprecise with our prose in this discussion. I
think what we really should be more specifically talking about is power
(Watts), not energy (Joules). Power is energy per unit time, i.e. Watts
= Joules/second. That is, there wasn't enough "power" to be had from
Helium fusion.

You can get more power by either having a more energetic fuel, or
burning a fuel more quickly. Helium fusion produces less energy than
hydrogen fusion, so stars that are in the helium stage stay in that
stage much shorter than they did in the hydrogen stage.

What I have trouble with is the idea that the outer layers stayed
around rather than wandering off. A huge accretion disc seems more
reasonable but that isn't mentioned in the article.

It's quite likely that these stars were oblong rather than spherical
around their spin axis. At 10 million solar masses it's more akin to a
whole galaxy undergoing fusion rather than just a star. Such a star
wouldn't produce too much light even before it became a black hole,
because it probably was already pretty close to the density of black
hole, most of the light would've been stretched way to the end of radio
wavelengths and then stretched even further by cosmic expansion over
these billions of years.

This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

Just goes to show, we don't know everything.

This star might have formed very similar to the 10 million SM stars,
where a whole region of a gas cloud just got so dense that it underwent
fusion without a lot of accretion needed.

Yousuf Khan

i.e. - q.e.

black hole - unicorn

On Dec 8, 5:50*pm, " wrote:
This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

* Just goes to show, we don't know everything.

* Mark L. Fergerson

Another thing to note is that before the discovery of this particular
star, the idea of a "pair-instability supernova" was just an
interesting theory. Similarly, the idea of a 10 million SM stars is
just an interesting idea at the moment, but who knows maybe one would
be discovered at some future date with a long-wavelength radio
telescope of the future? Maybe the thing will be mistaken for a galaxy
initially?

Yousuf Khan

Sounds like they're saying that the original stars may have been so
massive that once their hydrogen cores ran out of hydrogen, they simply
contracted straight to black holes. That is, there wasn't enough energy
left to be extracted from subsequent helium fusion to keep their cores
inflated, like we see with modern stars.

This reminds me of the recent discovery of a 200 Solar mass
"pair-instability" supernova which exploded even before it reached the
critical iron core stage where most supernovas explode. That star
exploded by the time it reached only the oxygen fusion stage. As we see
more and more massive stars that we're not used to seeing in the modern
age, we're likely to see more of these weird star death mechanisms that
we've never seen before.

Then it seems the rate of the star's spin changed to a level where the
star did
not have to come to a black hole, but span up and up. Without science
models
in computers this is hard to explain. Supernovas are an important
piece in
explaining dark matter.