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Jim Hawkins
2003-Jul-29, 10:22 AM
hey anyone knows vaguely what happens in a black hole?
heard if you got into a massive one with a smooth, gentle slope, a twirling one, you could get into some other world. then in that other world that black hole you have fallen into has become a white hole. instead of suckin you in it repels you
and if you got into a small, tight one,


too bad fer ya




bye bye and get stretched nice long and thin like spaghetti
youre dead

so izzit true? i wanna know.

so is it possible you can get into another universe through a big ole blackie? and get repelled violently by a whitie?

and wormholes.

you can get into some other place with juz one small step.

lame <_<

can anyone answer?

i need sensible advice.

juz gimme all youve got

so long

see ya

N3373H
2003-Jul-29, 09:59 PM
What you&#39;ve heard only happens in the movies.

A Black Hole is merely condensed matter that has such a strong gravitational pull that nothing except x-rays can escape. Not even light. We know that the matter doesn&#39;t go anywhere else because we can deduce the mass of a Black Hole by it&#39;s gravity. Gravity is the only thing that &#39;sucks&#39; in this case. No white holes either.

As for worm holes, they only exist in theory and even there they aren&#39;t large enough for even a worm to fit through (or even a molecule), and so unstable that the worm probably wouldn&#39;t make the trip in one piece anyway.

Just what I&#39;ve heard. Here&#39;s hoping a real scientist might answer your questions better. :rolleyes:

Fraser
2003-Jul-30, 12:56 AM
I think that the concept of white holes came about before Hawking&#39;s calculation that black holes actually evaporate away.

Going to a black hole wouldn&#39;t be romantic in the least, it would be a horrible way to die, getting stretched apart by the massive tidal forces.

N3373H
2003-Jul-30, 09:20 PM
Do they really evaporate away? How so? Where does the matter go? Is it all converted to radiation that cannot be held by the intense gravity?

kashi
2003-Jul-31, 05:17 AM
Visit. http://www.universetoday.com/forum/index.p...p?showtopic=274 (http://www.universetoday.com/forum/index.php?showtopic=274). I think there might even be another forum topic where these issues are discussed.

I recommend reading Hawking&#39;s literature which explains these concepts very clearly&#33;

Kashi :P

sanchez00
2003-Aug-05, 07:32 AM
Yes, blackholes do evaporate away. I think the name it was given is "Hawking Radiation". I&#39;m not positive but i think it has something to do with the second and third laws of thermodynamics. It&#39;s been a while since i&#39;ve taken the class, so i&#39;m rusty.

White holes are just mathmatic opposites of blackholes that would violate the laws of thermodynamics. The only way they would or could exist is in a nother universe that had different physical laws.

As for wormholes. It would either take an infinite amount of energy to hold it open or negative matter that has yet to be found in this universe. Just another mathmatical anomoly that would be cool if we could find.

megaquark
2003-Aug-23, 12:47 AM
In addition to being stretched thin because of the rapidly increasing gravity, you would accelerate to relativistic velocities which creates a problem with time. In effect, you would never reach the center. Kind of a quirk of the math.

Deep_Eye
2003-Sep-09, 11:02 PM
Who knows, Hubble can "only" view about 12 billion light years away. Who&#39;s to say that white holes can&#39;t exist. All that matter has to go somewhere......
Maybe its the universes way of recycling itself.....

zephyr46
2003-Oct-15, 02:27 AM
I wonder if wormholes are basically like astronomical twisters/tornadoes and the idea is to get sucked in one end and out the other, formed by passing stars, am I living in a dream world ?

Matthew
2003-Oct-15, 09:41 AM
A Black Hole is merely condensed matter that has such a strong gravitational pull that nothing except x-rays can escape. Not even light. We know that the matter doesn&#39;t go anywhere else because we can deduce the mass of a Black Hole by it&#39;s gravity. Gravity is the only thing that &#39;sucks&#39; in this case. No white holes either.

X-Rays cannot escape black holes either. No electromagnetic radiation can escape however powerful. This is because once matter (and light) go past the event horizon of a black hole you would need to go faster than the speed of light to escape. ;)

In the centre of black holes there is a singularity, in spinning black holes the singularity would be ring shapped (instead of the normal spheretical singularity), if you could travel through the centre of the ring singularity some people believe that you would go to a different universe (or something like that).

Black holes with smaller mass have very steep gravitational well. The larger black holes have shallower gravitational wells decresing spagettification. There are black holes so big in our universe (primarily in the centre of galaxies) that they suck up stars whole instead of just sucking in the gas. The spagettification of a black hole would be very small, and so you might be able to go into one this big (as long as it is a spinning black hole). If you calculate your trajectory exactly you may be able to go through the ring singularity. Where that would lead you...

Some theories floating around are: That all black holes send their sucked up matter to the big bang (recycling universe)
That you go to a baby universe where time runs backward and distances are negative.
That the universe is a black hole and other black holes are a seperate universe.
There are more theories.

Using quantum physics Hawking theorsised that black holes evaporate. This is all about virtual particals and how gravity pays the energy for these virtual particals to be real. So the photon (the virtual partical) goes out into space, thus black holes evaporating. Not all photons travel out into space, some go back into the black hole. Smaller black holes evaporate slower than bigger ones. It would take 10 to the power of 67 years for a stellar mass black hole to evaporate and die in a burst of gamma rays.

What happens at the centre, the singualrity? It is believed that there are 9 dimensions, with our normal 3 being curled and distorted to be the extra 6 dimensions as well. In the singularity gravity strangth changes billions of times in a second. Time also has no meaning with space-time being distoted so much when has no real meaning. :o

Haglund
2003-Oct-15, 10:12 AM
A black hole is a star that has collapsed in its last days as a star. Its density rised which caused it to collapse. The end result is a singularity, 10^-33 cm. Around this singularity is an event horizon. This is a black sphere around the singularity, but it&#39;s not a material sphere, it&#39;s just the distance from the centre where light cannot escape the black hole. A black hole is characterized by its mass and spin, and that&#39;s pretty much it, as far as I know. It could have a charge, I suppose, but it should quickly become neutral.

Now, I have read about some theories that suggest that a spinning black hole could have a circular singularity, which could possibly mean that one could travel quickly to another time or another place. How true this is, noone really knows.

Matthew
2003-Oct-17, 09:20 AM
Mini-black holes and mini- wormholes occur natuarllay all the time. Just to see them though you would need to be able to look at the scale of 10^-32 mm, and be able to freeze a frame for 10^-43 seconds. The mini holes occur naturally for very breif instances of time. These mini wormholes are also called quantum wormholes. But wormholes are unstable. To keep one open you need to insert antimatter, or a false vacuum. (A false vacuum is a vacuum with a high energy density). A false vacuum acts like antigravity and could keep a wormhole open.

You can also make wormholes from 2 neutron stars and false vacuum. All you need to do is get a neutron star, curve the space around it so its gravitational dent nearly touches your target location. Put your second neutron star at your target location. Add matter to both neutron stars, until they become black holes. A wormhole should form, insert some false vacuum tokeep the wormhole from shutting and there you go, you&#39;ve got yourself one wormhole&#33; ;)

Remus 007
2004-Jan-16, 12:00 AM
[FONT=Geneva] :ph34r: [COLOR=orange]I belive that a black hole does not evaporate it just super compreses matter and spits it away. From some thing I know it can spit matter up to 20 Light years away. Also I belive a white hole is just another science fiction story until I am proven wrong.

I also belive that a black hole can`t be escaped at all, because you would be shreded into atoms in miliseconds. A star the size of the sun can be sucked in by a black hole within 1,000 years from 3 light years away.

Remus 007
2004-Jan-16, 12:05 AM
A worm hole is of a subatomic scale the only way to make a wormhole suitable for a human would be in space. A sun powered laser wich could make a strong enough laser that when passed throu 13 filters it would make a worm hole big enough for a Blackhawk helicopter.

Matthew
2004-Jan-16, 12:49 AM
I belive that a black hole does not evaporate it just super compreses matter and spits it away. From some thing I know it can spit matter up to 20 Light years away. Also I belive a white hole is just another science fiction story until I am proven wrong.

Stephan Hawking has though, shown that they do evaporate away. And black holes do not spit out matter they have already past the event horizon. They only swing excess matter from their acceration discs (if they have one) in towo beams of fast flowing matter.

lazserus
2004-Jan-20, 05:43 PM
Stephan Hawking has though, shown that they do evaporate away.
This is only speculation. The calculation don&#39;t even come together very nicely on paper, because it involved performing quantum mechanical calculations in a curved space-time. This isn&#39;t very pretty considering general relativity and quantum mechanics don&#39;t agree.

They only swing excess matter from their acceration discs (if they have one) in towo beams of fast flowing matter.
If a black hole is, in fact, a black hole (meaning it has an event horizon and a mass) then it&#39;s going to have an accretion disc. We assume that a naked singularity would not have any form of accretion disc.