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Carpe Diem
2002-Apr-21, 07:37 AM
The very first thing I should do is proclaim my ignorance. I'm straight out of high school so this will probably sound like the ravings of a misinformed idiot.

But to get to the point...

I was wondering how plausible the following theory would be.

(I'll assume that anyone reading this knows what black hole are and how they are formed.) As far as I know black holes have an infinate life, therefore over billions of years they suck up an incredible amount of stuff, and keep getting bigger and stronger as their mass increases. It would stand to reason (well my reason anyway) that one strong black hole could devour another and so on and so on, in the process this black hole would get bigger. It would then be possible, given enough time, for a black hole to suck up all the matter in the universe. We would then be back to where we were before the big bang, all the matter in the universe compressed in one highly dense ball. Which could then explode under its own gravity and start off another universe, more black holes would form and suck up the universe again. Creating a vicious cycle in which the universe is destroyed and created many times over.

I have a vauge knowledge of the collapsing universe theory (where eventually the universe starts to collapse under its own gravity), would it not be possible for black holes to be the cause of this collapse?

Even then you still get one nagging question... At some point something had to come from nothing - right?

<font size=-1>[ This Message was edited by: Carpe Diem on 2002-04-21 03:37 ]</font>

John Kierein
2002-Apr-21, 11:22 AM
Why does something have to come from nothing? That violates the conservation laws of physics. Maybe the something was always there. Endless boundless stable universe.

Kaptain K
2002-Apr-21, 12:08 PM
1) The lifespan of a black hole, while long, is not infinite. They do lose mass due to Hawking radiation.
2) The Schwartzchild radius of a black hole with the mass of the universe would be on the order of the observed radius of the universe (several billion lightyears).

GrapesOfWrath
2002-Apr-22, 08:21 AM
Sounds like the Big Crunch (http://www.sciencenet.org.uk/database/Physics/Cosmology/p00719c.html) theory. Do a google on big crunch, but be careful, you might end up with things like this (http://www.its.caltech.edu/~dg/crunch.html).

<font size=-1>[Fixed URL]</font>

<font size=-1>[ This Message was edited by: GrapesOfWrath on 2002-04-22 04:21 ]</font>

Argos
2002-Apr-22, 12:38 PM
Black holes are nested within galaxies. You should take into account the expansion of the fabric of the universe. This expansion outruns the weak and slow gravitational attraction by the BH's inside galaxies. You are proposing a version of the Big Crunch hypothesis, which is by now unconfirmed, since it seems that the universe will expand forever due to the lack of matter.

Swaping the subject, how fares the skies down in NZ? I'm in the southern hemisphere too, and the region around south celestial pole looks great! Take a look at Carina, Puppis and Vela. They are in great shape.

2002-Apr-22, 01:12 PM
<a name="20020422.4:59"> page 20020422.4:59 aka Math hour in 1 min
On 2002-04-21 03:37, Carpe Diem wrote: To: 8 KAN 18 POP
1: First i'll say "Tanks" for lines to Xploit
2:
But to get to the point...3:
4: and now 4My arguement. I see you collapse
5: the "BLACK HOLE" to a sphere?
6: My interpritation! of....
7:..pressed in one highly dense ball.
8:{of course it could be a foot ball?
9:So why do you think thataway?
8:Why not a Cubic, or Tetrahedron?
7: hmm? or even some other figure?
6: Listen, if you like, I don't see them
5: this way I see them more like holes in
4: cheese. different Mater not all self contained. in other words there my be stuff beyound UNIVERSE`s.

2002-Apr-22, 01:25 PM
<a name="20020422.5:18"> page 20020422.5:18 aka Math Hour 4Me
On 2002-04-22 04:21, GrapesOfWrath wrote: To: 5:20 A.M. PST
your sence of the radical
never ceases to inpress me!
Yes, i reamain on PST on this 386/20
the 486/100 shifted over to daylight time
on its own. ..I.. use it very little..
Mostly listen to Anita O'Day
Rules of the Road... Wave... etc

Argos
2002-Apr-22, 05:51 PM
Carpe Diem, don't mind about Hub'. Most of us don't understand what It writes. (It is a computer onboard a ship heading to the Kuiper belt). /phpBB/images/smiles/icon_smile.gif

<font size=-1>[ This Message was edited by: Argos on 2002-04-22 13:53 ]</font>

Bob
2002-Apr-22, 07:38 PM
On 2002-04-21 08:08, Kaptain K wrote:

2) The Schwartzchild radius of a black hole with the mass of the universe would be on the order of the observed radius of the universe (several billion lightyears).



I get a different answer for such a Schwartzchild radius on the back of my envelope. The Schwartzchild radius is
R = G * M/ c^2
For the mass I used 2 * 10^30 kg (known mass of the sun) times 10^16 stars in the universe (very fuzzy number). This works out to 10,000 light years.

Carpe Diem
2002-Apr-23, 12:46 AM
Thanks everyone for your answers, you've helped me understand it much better. (I knew it couldn't be that easy)



On 2002-04-22 08:38, Argos wrote:
Swaping the subject, how fares the skies down in NZ? I'm in the southern hemisphere too, and the region around south celestial pole looks great! Take a look at Carina, Puppis and Vela. They are in great shape.


In actual fact the sky is determined to hide itself at the moment. I havn't been able to get a look at the planetary alignment yet. I'm hoping to go and find a nice high mountain one night in the next week and have a good look without the clouds hanging around. I'll make sure to take a look at the above - thanks

[fixed typo]

<font size=-1>[ This Message was edited by: Carpe Diem on 2002-04-22 20:47 ]</font>

Bob S.
2002-Apr-23, 04:57 PM
On 2002-04-22 09:12, HUb' wrote:
I see you collapse
5: the "BLACK HOLE" to a sphere?
:
8:Why not a Cubic, or Tetrahedron?
7: hmm? or even some other figure?

Heh heh, cute!
"Scotty, we're being sucked into the gravity well of a Black Decahedron! We need warp speed now!"
"Bu' Captain, we haven't go' enuff powah!"

Martian Jim
2002-Apr-26, 11:55 AM
on 66th margyuary (martian date) Martian jim wrote to himself and others

1)why do you
2)guys have to
3)speak like this
4)cutting up you
5)sentances into
6)some sort of
7)scary looking
8:list?

_________________
the guy that has come from mars, for no reason (no reason, or you think for no reason......)

<font size=-1>[ This Message was edited by: Martian Jim on 2002-04-26 07:56 ]</font>

Silas
2002-Apr-26, 06:12 PM
On 2002-04-26 07:55, Martian Jim wrote:
on 66th margyuary (martian date) Martian jim wrote to himself and others

1)why do you
2)guys have to
3)speak like this
4)cutting up you
5)sentances into
6)some sort of
7)scary looking
8:list?

_________________
the guy that has come from mars, for no reason (no reason, or you think for no reason......)

<font size=-1>[ This Message was edited by: Martian Jim on 2002-04-26 07:56 ]</font>


P-KB3
NaCL
lim x>0 1/(x^2)
20mg bid
2rm riv vw 1/2bath
rm -r *
FOB 90210
E. coli

(grin!)

There once was an alien named Hub'
Whose syntax was trouble to dub'
We love him no less
tho' his writing's a mess
For his science cuts straight to the nub'

Silas

2002-Apr-28, 11:56 AM
<a name="20020428.3:49"> page 20020428.3:49 aka 1 OC 4 UO
On 2002-04-23 12:57, Bob S. wrote: To: 1 OC 4 UO
Yep, preCISILY: now to my other point.
forget the BIG question
consentrat for a week
just on the Sun
how it begun
at what rate it spun
& then do a reRUN
--------------------
Heh heh, cute!
"Scotty, we're being sucked into the gravity well of a Black Decahedron! We need warp speed now!"
"Bu' Captain, we haven't go' enuff powah!"

rrODgr' OVAL & out``

DJ
2002-Apr-28, 11:57 AM
How would we know if we were not inside a black hole right now?

DJ

John Kierein
2002-Apr-28, 02:55 PM
Because we're inside a gravastar according to these guys.
http://www.space.com/scienceastronomy/astronomy/gravastars_020423.html

Personally, I think they have their head up a black hole. There is no gravitational effect from a spherical shell when you are inside it.

Martian Jim
2002-Apr-29, 01:59 PM
On 2002-04-28 07:57, DJ wrote:
How would we know if we were not inside a black hole right now?

DJ


i think that we would know that because we would be crushed to a pulp, we would not see any stars and there would be alot of gravity.

also my ufo would not be able to fly /phpBB/images/smiles/icon_wink.gif

Conrad
2002-Apr-29, 02:12 PM
On 2002-04-28 07:56, HUb' wrote:
<a name="20020428.3:49"> page 20020428.3:49 aka 1 OC 4 UO
On 2002-04-23 12:57, Bob S. wrote: To: 1 OC 4 UO
Yep, preCISILY: now to my other point.
forget the BIG question
consentrat for a week
just on the Sun
how it begun
at what rate it spun
& then do a reRUN
--------------------
<snip>
rrODgr' OVAL & out``


Well, for the first time I can remember, one of Hub's posts makes complete sense to me. However, once he returns to science and not rhyme, I'm sure things will return to normal.
/phpBB/images/smiles/icon_smile.gif
Pip pip!