Journey Into A Black Hole

[StarMountainKid]

This movie is taken from this website:

http://jila.colorado.../realistic.html

There is a wealth of information about this video and black holes on this page, and by clicking on the tabs on top of the page there is more to read and view. Maybe we can discuss some of this as well.

Edit: movies from this page will not play on Windows Media Player, I use free VLC Media Player which is much better than WMP anyway.

[media=]

[/media] Edited September 14, 2013 by StarMountainKid

[freetoroam]

Were did they get the info from to create this "realistic" black hole?

It says the burst of light contains the entire history of the Universe, how do they know that?

[StarMountainKid]

Were did they get the info from to create this "realistic" black hole?

It says the burst of light contains the entire history of the Universe, how do they know that?

I'm no expert (definitely not), but I think one reason could be, as time slows down for you falling into the black hole relative to the outside universe, you would see time in the outside universe speeding up. Inside the black hole, spacetime is falling toward the singularity faster than the speed of light, so in a sense, if you look up you see time in the outside universe speeding up as it approaches you faster than c. I'm probably wrong here and not qualified to give an answer anyway. This is just how I try to understand it. I think it's more complicated to explain in words than in the math.

At the inner horizon, you are hit by an infinitely bright, infinitely energetic burst of light. The bright point of light is an image of the outside universe reflected by the gravitationally repulsive singularity. The burst of light contains, infinitely speeded up, the entire history of the universe.

The infinitely bright burst of light signals the breakdown of the Reissner-Nordström geometry. The Reissner-Nordström geometry assumes that all matter and charge inside the black hole is concentrated at the central singularity. The assumption leads to the prediction that light from the outside universe concentrates infinitely at the inner horizon,

From my link.

I think a complete understanding of the weirdness of black holes takes a lot of research and a lot of thought.

[sepulchrave]

That is a good site, StarMountainKid. The author(s) seem to have done a very thorough and accurate job.

Were did they get the info from to create this "realistic" black hole?

See the mathematical notes at the bottom of the page.

It says the burst of light contains the entire history of the Universe, how do they know that?

The website shows the simulation of the electromagnetic Poynting vector in a Reissner-Nordstrom black hole (charged but not rotating).

In this case there are two event horizons. The inner one (the ``Cauchy horizon'') is a trap for speed-of-light geodesics. In other words, if you can (somehow) travel faster than the speed of light you can escape out from the inner horizon. If you are limited to travelling slower than the speed of light you will never escape and will fall towards the centre of the black hole. And if you are travelling exactly at the speed of light you will circle around the black hole forever one this inner horizon.

Since light is (obviously) travelling at the speed of light, all the light that has ever entered this black hole will be trapped at that point.

This doesn't really contain the entire history of the Universe, since the very early stages didn't have any light. But everything since then will be trapped at the inner event horizon.

Even light from events which happened before the black hole was formed can be trapped here, as long as those events happened far enough away from the black hole.

So it is a bit of an exaggeration to say ``the entire history of the Universe'', but it sounds poetic and isn't totally incorrect.

[freetoroam]

So it is a bit of an exaggeration to say ``the entire history of the Universe'', but it sounds poetic and isn't totally incorrect.

Its these bits which confused me, hence "how realistic is this black hole "?

From the article:

***SNIP***

Edited September 15, 2013 by Waspie_Dwarf
plagiarism

[Waspie_Dwarf]

frretoroam

You are going to have to rephrase your question without copying vast amounts of text from another site.

A reminder of the rules on this:

2c. Plagiarism and copyright: If you quote text from an external web site then please always provide a source link. Members are asked to copy only as much as is necessary when quoting material from external sources, do not copy and paste entire articles or web pages. ( See our Sourcing FAQ )

[sepulchrave]

Its these bits which confused me, hence "how realistic is this black hole "?

The black hole itself isn't realistic, a real black hole would almost certainly be rotating.

The simulation is fairly realistic; the differences between the proper geometry for a rotating black hole and a non-rotating one don't significantly affect what you would see.

The colour is not realistic; you wouldn't see the same colours if you actually fell into a black hole. (A lot of the light you would see would be in the UV or X-ray range, so you might get cooked pretty quickly but you wouldn't see much.)

You can't really see the entire Poynting flux directly, so that part isn't realistic either.

Basically this simulation shows a lot more detail than you would actually ``see'' if you had the misfortune to fall into a black hole.

I think if a person actually did fall into a black hole they wouldn't be able to see very much; most things would be too cold or too hot to emit visible light.

If you had access to the appropriate sensors then I think this simulation is pretty realistic.

[freetoroam]

Sepulchrave,

I think I am getting where you are coming from.

This seems to be the future for man in terms of finding out what really is out there....computer simulations. I do not believe man is physically capable of such a long haul explorations and never will be, no matter what rocket they have in the future, so with all the wonders which are being made and what has been made and are still out there, computers ARE our eyes to the Universe and always will be.

[freetoroam]

frretoroam

You are going to have to rephrase your question without copying vast amounts of text from another site.

A reminder of the rules on this:

What I copied was from the article in the link, I only took the section which was relevant, I did not copy the whole thing.

Hence why I put this first:

"Its these bits which confused me, hence "how realistic is this black hole "?

From the article:

etc etc etc!

[Saru]

What I copied was from the article in the link, I only took the section which was relevant, I did not copy the whole thing.

You don't need to copy the whole thing for it to be too much, one or two sentences and a source link should be optimal.

[justcalmebubba]

~~spock, aum yes capt, what doyou make of this? well logic would sugust its a hole, a hole? instresting...... a hole indeed so scotty give us all she's got ...capt? oh sit down and strap your vulcon ass in

we'r star traking across the univerce only going forward cause we cant find reverse

[StarMountainKid]

The black hole itself isn't realistic, a real black hole would almost certainly be rotating.

Thanks for your input, sepulchrave, as always. The author of the page states the video is not of a rotating black hole on this page:

The geometry is that of a charged (Reissner-Nordström) black hole (with charge-to-mass 0.9), not a rotating (Kerr) black hole. That is simply because I have not yet implemented rotating black holes in the BHFS. It is not a limitation of Hawley's simulation, which was done with a Kerr geometry. The excuse is that the interior structure of a non-rotating charged black hole resembles that of a rotating black hole in that both have an inner horizon where the mass inflation instability takes place. One day I hope to implement rotating black holes in the BHFS, but it will require a major investment of time and effort.

http://jila.colorado.edu/~ajsh/insidebh/realistic.html

The author states that the singularity of a rotating black hole would actually be a ring or a doughnut shape because of centrifugal force. Here's another page on black holes. About half-way down the page is, "What's So Special About A Ring Singularity?".

http://www.gothosenterprises.com/black_holes/inside_black_holes.html