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in other non-political news, the confimation on a black hole in the center of the galaxy has put a lot of already asked questions into my head like:

1. will we get sucked in?
2. where does the matter go; is it shot out the back, behind the gravitational distrubance? is it warped into some other universe with the grav/time thang?
3. do smaller black holes exist, or are they really just an effect of the energy on central galaxy creation?

I wish I had a job where I could just ask a lot of questions and get answers. I guess that would be school.

Better get back there.

Comments

( 12 comments — Leave a comment )
htj
Oct. 17th, 2002 02:18 pm (UTC)
You need to be a geek :)

1. We won't get sucked in since the gravitional force of the mirror universe is making everything fly apart.
2. The matter gets compressed into a single point - a socalled singularity. I seem to remember something about this singularity having no dimensions in normal space.
3. When a big enough star dies, the gravity generated by its mass makes it compress into a tiny point. If it's not big enough, you get a pulsar.

mr_mooph
Oct. 17th, 2002 02:21 pm (UTC)
oooh, boy....let me see here.
Ok, first off, let me state that I am not a physicist. Hell, I only have a BA and that in the theatre, but I shall do my best here from what I CAN remember in my readings....

1) Well, WE won't get sucked in. It would be well past our lifetimes by the time it did happen. In general though, I think this relies on weather the universe will continue expanding It has to do with the conservation of energy I belive, but I cannot really speak to this one at this point.

2) There is no front or back for the matter to shoot out of. Gravity radiates in all directions and therefor passing matter and energy is pulled in from all directions. I'm assuming that you're equating the disc typically shown with a front and a back. This is caused by particles rotating around the black hole that have not been sucked in yet. (there is a specific rate that the accumulate matter by) In fact, (if I'm not mistaken) when black holes are at the center of galaxys, it is when they start acquiring matter faster than they can "eat" it that galaxys and the like for because this disc gets bigger and bigger and things (stars etc) begin to coallese. It is the gravitation of the black hole then that prevents the remainder of the galaxy from flying off in their own directiosn through space. When it finally does collapse into the hole, the matter gets ripped apart into the smallest subatomic particles and are added to the singularity increasing it's radius.

3) I'm not sure what you're asking here. They do come in different sizes. Determined by how much they have been "fed" (and going unfed, they will disipate after a long long LOOOOOONG time.) They're not all going to be as massive as the ones that hold galaxies together. I have also heard of "mini-black holes" Now, I'm not sure what the deal is behind these things, but I remember some scientists saying they wanted to recreate the conditions of the big bang and the creation of mini-black holes could be one effect. Now granted, this is way out of my league, but creating mini black holes, much less recreating the big bang within the universe did not sound like a good idea. >smirk
jpjohnsn
Oct. 17th, 2002 04:06 pm (UTC)
Black Holes and Stuff
Oooooo ooooo! I know some of these!

1. No, we (or our decendents) won't get sucked in because the galaxy's spin is actually throwing us away from the core. The force of gravity exerted by the black hole on us is getting weaker and weaker.

2. All the matter falls to the centre where it is crushed into a singularity of no dimensions. The NEAT thing is that Black Holes aren't permanent. I read Stephen Hawkings book and here is what I understand happens: Quantum theory indicates that even in empty space, particles can spontaneously form. Suddenly there appears, for example, one proton and one anti-proton (matter and anti-matter) which then recombine and annihilate each other. Sometimes, when this occurs very near a black hole, an anti-proton will fall into the black hole. This has the effect of making the black hole smaller by one proton and leaving one proton free in space - just as if a proton had escaped from the black hole. As well, the anti-proton's annihilation releases energy in the form of radiation that squirts out in a big jet. The blackhole slowly dissapates and eventually dies in an explosion. Like Shakespeare said "There are stranger things in heaven and earth than are dreamt of in your philosophy"

3. Other than the (crackpot) theory that the Tunguska Explosion in Siberia back in the early 1900s was a mini black hole rather than meteorite or comet that came to earth, I've ready nothing on the subject.

Phun with Physics. :-)
lisagoddess
Oct. 17th, 2002 06:03 pm (UTC)
ok, it sems i am most fascinated by answers to question 2. Now, im trying to really imagine this thing. I did a report on balck holes when i was in..i dunno 7th grade. one of those reports where the teacher warns you to use as least 3 books other than the encyclopedia.

anyway, my memory holds this picture of an infinate plane with stone dropped in the "center" falling infinately. im trying to place this again. what the significance was exactly..it'll come to me with a hint.

also, the idea of a black hole breaking apart...the matter/ anti-matter idea...how can a proton or any other particle be formed randomly? according to some other science class, energy cannot be created or destroyed, only changed. So, where does the proton come from? (or anti-proton) did it wink out in one place to pop up in another? is the black hole collasped to a point as well? this doesnt make sense if they become so huge. and when it collapses...where does all the matter go...does it expand again? and wait..what abaout this mirror universe that mr mooph (right? I cant look back) mentioned....

i NEEED to know! where's chexmix when you need him?
(Anonymous)
Oct. 17th, 2002 08:28 pm (UTC)
The black hole itself is a singularity. By bigger, what is really meant is "more dense", which according to gravitational theory implies "bigger field of influence". All of the matter is contained in the single point.
ex_bloody_an630
Oct. 17th, 2002 08:57 pm (UTC)
Well black holes were, until recently, only theory. But, the thing about a proton and anti-proton forming spontaneously isn't creation of matter. Conservation of matter and energy is still a law. What is happening is energy becomes matter (and vice versa) under certain conditions. One of these conditions is during nuclear reactions such as that of a nuclear bomb being detonated (the source of that massive energy blast is matter being converted into energy and then back) and it is also what fuels stars. In space, there is a substance known as dark matter, which was discovered by looking at the effect of gravity and heavenly bodies and all that and they found that there was a substancial amount of matter in the universe that was unaccounted by stars and planets, and this matter is called dark matter. It's just out there and we can't really see it, only it's effect. Sort of like black holes (which some believe is a large concentration of dark matter) which you can see the effect of it but you can't really see IT since any light that you send to look at it would get absorbed. But you can see the bending of light the stream of matter being pulled into it if you look the right way. Anyway... so either by interaction with a star or more likely a black hole, minute nuclear reactions occur and protons and anti-protons are created and then they destroy each other (convert back to energy). The only real reason to mention this is as a curiosity, except if a large quantity of protons were being emitted by a singularity which would indicate that it had collected so much matter that it was imploding under it's density and all that matter was going to be released. The scary thing is if it's anti-matter (anti-protons) that is being emitted because this could cause an explosion of big bang proportions (and is likely the cause of the original big bang) which if that occured in the universe as it exists now, lots of weird crazy stuff would happen in the next few billion years which we wouldn't be able to watch....

Now that I've completely made myself sound like a geek, I'll shut up. Hopefully some of that is coherant. :)
(Anonymous)
Oct. 17th, 2002 07:19 pm (UTC)
black hole sizes
If black holes DO come in different sizes, I take a 44 regular.
(Anonymous)
Oct. 17th, 2002 11:03 pm (UTC)
"who knows where the time goes?"
hi lisa!

2. where does the matter go; is it shot out the back, behind the gravitational distrubance? is it warped into some other universe with the grav/time thang?

that's the essential thing about black holes. they are "black" -- that is, no light or matter come out from them once it has become trapped, so there is no information about what "happens" in them -- and they are "holes" -- that is, things (energy and matter) fall into them and can't get back out.

of course, if it were only that simple. as someone pointed out above, hawking has theorized (no one has conducted an experiment demonstrating his theory yet, what with the shortage of black holes at the hardware store for such things) that black holes "leak" over time, apparently due to some quantum uncertainty principle, or some such. the leakage is very slow and expected to go on for eons (i forget the order of magnitude -- billions of years? hundreds of billions?), but in time enough of the black hole could leak (away from the hole's grasp and back out into the "normal" universe) out that the black hole would no longer be a black hole.

-mjm

p.s., sorry i missed the iraq debate.
r_lu
Oct. 18th, 2002 10:40 am (UTC)
Howstuffworks.com
jpjohnsn
Oct. 18th, 2002 01:49 pm (UTC)
Black Holes and Stuff
lisagoddess
Oct. 21st, 2002 10:06 am (UTC)
Re: Black Holes and Stuff
thanks ill check it..and the one from R-LOO too!
legolas
Oct. 22nd, 2002 02:45 pm (UTC)
disc with jets
afaik, the classic image of the black hole as a disc with jets, is what happens around the hole, not inside it. Matter compressing as it falls toward the hole creates such energy that some of it can be shot away from the vicinity of the hole (not from inside the hole).

As for the proton/anti-proton creation: the idea is that for some (unknown I think) reason, these two appear, but since they are each-others inverse, no mass or energy is really created. in other words there is 0, and it creates 1 and -1. if they come back together, you have 0 again, but sometimes the -1 is pulled away from the 1 and you get both of them separately.

Other strange quantum things I know little about talk about these 2 (the 1 and -1) have some sort of connection which also keeps there spin oppsite. So if you were to change the spin of the 1, even if at the other end of the universe, the -1 would also change. Or something like that anyway. Someone enlighten me ;-)
( 12 comments — Leave a comment )