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420chan is Getting Overhauled - Changelog/Bug Report/Request Thread (Updated April 10)
Non-stellar black hole Ignore Report Reply
Alan Guth - Sun, 30 Mar 2014 23:19:17 EST ID:ZhOAg7La No.53409
File: 1396235957344.jpg -(1526332B / 1.46MB, 1728x1224) Thumbnail displayed, click image for full size. 1526332
OK, odd question but...well marijuana is what...

Here we go - Is a non-stellar black hole theorhetically possible?
Imagine no restrictions of the creation of it. You have an unlimited supply of dense matter to throw into a big old sphere. Say, I dunno...Iron. Unlimited iron. You can just throw that shit by the teraton into one even pile.

I mean, you could create a black hole eventually, right? It would get really fucking hot at first...molten...then maybe some sort of weird plasma? But we keep throwing on the mass. Using special Future Magic to keep shit contained. You get a black hole at some point, right?
>>
Anders Angstrom - Sun, 30 Mar 2014 23:32:40 EST ID:GjenEILY No.53410 Ignore Report Reply
If you put enough mass in one place, eventually it'll start fusing - and therefore be a star, even if for only a brief time.
>>
Alan Guth - Mon, 31 Mar 2014 00:32:19 EST ID:ZhOAg7La No.53411 Ignore Report Reply
>>53410
Well, yeah, I mean it would start doing some shit like that. But what doesn't iron basically poison the fusion reaction? Iron being the highest fusion in a star can reach. Everything else has to get made in a nova.
Point is, as long as the radiation pressure doesn't get too high, the thing will collapse with more mass getting thrown in.
>>
Caroline Herschel - Mon, 31 Mar 2014 03:21:39 EST ID:d+uYYbmP No.53412 Ignore Report Reply
You'd get a white dwarf and then a neutron star before you made a black hole.

It would be easier to make tiny, short-lived black holes by colliding two particles together at high energy. This is one of the aims of the LHC.
>>
Johan Galle - Mon, 31 Mar 2014 10:10:40 EST ID:kviwdVC/ No.53413 Ignore Report Reply
>>53411
Not everything; really big stars even fuse Iron, despite the energy loss.
http://en.wikipedia.org/wiki/S-process

The math for this kind of thing is a bit fuzzy; some of the data doesn't quite fit the model.
http://en.wikipedia.org/wiki/P-nuclei
>>
Chushiro Hayashi - Mon, 31 Mar 2014 13:35:29 EST ID:Jzd78Ub0 No.53415 Ignore Report Reply
>>53413
What i don´t get, is how do the iron/or other substances and stuff get spread around by supernovas? I mean, how does it take form into hard dense material when it shoots from the star?
>>
James Elliott - Mon, 31 Mar 2014 16:44:57 EST ID:SK5JnbMy No.53417 Ignore Report Reply
>>53415
When a star goes supernova, there is a slight time in which it fuses the heavier elements. Even though its only a small time, the sheer amount of material in the star going supernova will generate alot of heavier elements. At first they're gas I guess when they first shoot out during the supernova, but over time they condense to form shit.

So it doesn't shoot out as hard, dense material, it coalesces into that form. However, the atoms are already what they are, ie iron.

I dunno man, I'm sleepy as shit.
>>
Annie Cannon - Thu, 03 Apr 2014 05:54:33 EST ID:clO5e2NU No.53440 Ignore Report Reply
>>53412
but if you kept adding mass to the neutron star, wouldn't it eventually become a black hole?
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Charles Bolton - Fri, 04 Apr 2014 06:34:59 EST ID:d+uYYbmP No.53450 Ignore Report Reply
>>53440
Yes.
>>
Giuseppe Piazzi - Mon, 07 Apr 2014 06:20:25 EST ID:LYiJnGjH No.53457 Ignore Report Reply
http://en.wikipedia.org/wiki/Schwarzschild_radius

beyond that wiki page, yes if you throw enough of any matter it will become a black hole after a certain threshold.
>>
Johannes Kepler - Thu, 17 Apr 2014 21:58:06 EST ID:WXDai95U No.53517 Ignore Report Reply
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>>53409
>Unlimited iron
Iron is one of the final byproducts of nuclear fusion until it crumples into protons.

Also, this book is relevant to this thread.

In it, the author describes a process of using electromagnetic ramjets to shovel huge clouds of interstellar gas together and making an artificial black hole at a stable orbit around our star, just outside our solar system. As a matter of fact I think he said that we would start orbiting around the artificial black hole instead of the galactic core.
>>
Jericho !.iRAtomic2 - Sat, 19 Apr 2014 13:55:43 EST ID:Bw5xbsOS No.53528 Report Reply
>>53409
From my perspective, this does not seem possible. If enough mass of lighter elements comes together, it will become a star long before it becomes a black hole. If enough mass of heavier elements comes together, it will not become a star, but, depending on the ratios of elements in it, is likely to attract enough lighter elements to begin some level of fusion and become a star, long before it is massive enough to become a black hole.

For an analogy, I believe what you are talking about would be the equivalent of trying to build a 100 story building, without it ever being a 50 story construction site.
>>
Jacob Kapteyn - Sat, 19 Apr 2014 15:10:21 EST ID:WXDai95U No.53529 Ignore Report Reply
>>53528
In the book he explains the process of turning interstellar gas into black holes and backs it up with mathematics at the back of the book.

Of course, this book was written in 1977 so our understanding of the universe may have changed since then.
>>
Galileo Galilei - Thu, 29 Jan 2015 18:08:53 EST ID:GXbX/Jx+ No.54960 Ignore Report Reply
Let's say we did this same experiment, but with a much heavier element that is not typical fusion fuel, say bismuth. What would happen then?
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Johannes Kepler - Fri, 30 Jan 2015 23:44:48 EST ID:OXINl/7g No.54968 Ignore Report Reply
I think that once you reach a certain mass, you get a star anyway. Enough mass means gravity causes so much heat and pressure that fusion starts. Then, you keep adding mass until the gravity overcomes the outward pressure exerted by the fusion process, and it collapses into a black hole.

...right?
>>
Cecelia Payne-Gaposchkin - Sat, 31 Jan 2015 02:08:54 EST ID:R3QO2Nl1 No.54969 Ignore Report Reply
Primordial black holes might exist:
http://en.wikipedia.org/wiki/Primordial_black_hole

But stellar black holes might not:
http://www.huffingtonpost.com/2014/09/29/black-holes-dont-exist_n_5885940.html
>>
Bernard-Ferdinand Lyot - Sat, 31 Jan 2015 05:35:11 EST ID:YHjXylC8 No.54970 Ignore Report Reply
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>>54969
Re: Stellar black holes
How would they explain the sometimes invisible objects at the center of most galaxies that appear to contain in some cases, billions of stellar masses?
>>
Cecelia Payne-Gaposchkin - Sat, 31 Jan 2015 09:00:41 EST ID:R3QO2Nl1 No.54971 Ignore Report Reply
>>54970
From what I saw, the paper addressed the mechanics of collapse taking into account Hawking radiation, and didn't attempt to interpret apparent evidence of black holes.
>>
Gerard Kuiper - Sat, 31 Jan 2015 09:32:52 EST ID:ZM0jvM6N No.54972 Ignore Report Reply
>>54969
>http://www.huffingtonpost.com/2014/09/29/black-holes-dont-exist_n_5885940.html

The paper is widely not accepted, firstly the evidence for stellar mass black holes is strong. Secondly treatment of negative energy in the paper may have caused the clashing result.
>>
Cecelia Payne-Gaposchkin - Sat, 31 Jan 2015 11:42:57 EST ID:R3QO2Nl1 No.54974 Ignore Report Reply
>>54972
Sure, but that doesn't make the mechanics of collapse uninteresting nor does it completely invalidate the conclusion. I said "might not", not "don't".
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Vera Rubiin - Sun, 01 Feb 2015 12:52:33 EST ID:ZM0jvM6N No.54977 Ignore Report Reply
>>54974
It invalidates the claims of the paper, which were wildly exaggerated in the press release.
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Annie Cannon - Wed, 04 Feb 2015 15:26:13 EST ID:ksAXy5yQ No.54989 Ignore Report Reply
>>54971
And of course huffpo has to interpret that as "black holes don't exist".
>>
Ejnar Hertzprung - Sun, 08 Feb 2015 11:59:09 EST ID:bB14fKim No.55006 Ignore Report Reply
>>54989
That wasn't huffpo's interpretation, it was the author's conclusion. Basically, Hawking radiation got amplified in the nova and caused the core to lose mass fast enough that the Schwarzschild radius never exceeds the core mass. The paper essentially says stellar black holes can't form. Relating that math to empirical evidence is a topic for a few more papers.
>>
Henry Draper - Mon, 09 Feb 2015 04:25:13 EST ID:ksAXy5yQ No.55013 Ignore Report Reply
>>55006
Actually, maybe there's no problem with it not existing.

I'd think that something that didn't exist in this universe would be more striking than something that did exist, in this universe of existence.

That is to say, the chunk of nonexistence that is known as a black hole is still an anomaly with an observed effect, but only because it starkly contrasts it's existing surroundings. Perhaps the black hole is not pulling things in, perhaps the universe itself is trying to push back against an area that merely ceased to exist.

Like the hole in a doughnut. There is no hole, they don't manufacture the doughnut holes (even though there's doughnut balls called doughnut holes) The doughnut is merely shaped as if it has a hole.

None of this makes sense, their conclusion is doo doo. I'd like to see them fly into a black hole and tell me it doesn't exist.
>>
Arno Penzias - Mon, 09 Feb 2015 11:08:46 EST ID:ZM0jvM6N No.55014 Ignore Report Reply
>>55006
>Supernova*
A nova isn't the same thing as a supernova which involve black holes.

The paper claims it will not impact observations as you get something that is for all practical purposes a black hole. This is a debate for theorists and many have pointed to a number of grand assumptions made on the paper.
>>
Johannes Kepler - Mon, 09 Feb 2015 12:59:51 EST ID:YHjXylC8 No.55015 Ignore Report Reply
>>55014
>you get something that is for all practical purposes a black hole
Where are you reading that? As far as I can tell, it's effectively saying "When we do calculations this way, it says the collapse reverses before the is compressed beyond its Schwarzschild radius, causing everything to explode away."
http://arxiv.org/pdf/1409.1837v1.pdf
>>
Wilhelm Beer - Tue, 10 Feb 2015 13:11:50 EST ID:ZM0jvM6N No.55020 Ignore Report Reply
>>55015
It's from one of the other papers published by the author. I'm not sure if that's still what she thinks.
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Robert Dicke - Tue, 10 Feb 2015 23:49:27 EST ID:415JX8nG No.55022 Ignore Report Reply
It doesn't matter what element it is made of, it is strictly a measure of total mass.
A earth mass of iron would be a planet, a solar mass of iron collapses into a neutron star.

Iron nuclei are much more massive than hydrogen and helium, remember the real implications of the periodic table.
>>
Margaret Burbidge - Fri, 13 Feb 2015 19:53:11 EST ID:4HbkLal6 No.55030 Ignore Report Reply
1423875191278.gif -(505454B / 493.61KB, 200x200) Thumbnail displayed, click image for full size.
>the universe started when a bunch of shit got thrown together


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