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| Black holes...help!
Posted: 5/16/2007 4:35:51 PM | Jerry said
You don't see stars. You see light that they had emitted. If a star 1,000ly away blew up 500 years ago and was now completely gone, and you looked up in the sky at it, you would still see it; and you will for another 500 years.
Actually this has been argued recently they are now saying that what we see at that moment in time is in the now and that we cannot see the past  | |
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| Black holes...help!
Posted: 5/17/2007 10:12:07 AM | | Who's saying that? That'd be like saying we hear lightning as soon as it strikes rather than having to wait for the sound to get to us. The same applies to light. We won't see something until the light from it reaches us. | |
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| Black holes...help!
Posted: 5/17/2007 6:43:32 PM | "time is in the now and that we cannot see the past"
Well yeah. All we see is a never ending string of now but that does not mean an effect that has happened in the past can't be seen until the now and that we can't conclude that all we are seeing is an effect from the past. What made that effect may be doing something entirely different in the now that won't be observed from from those at a distance until the future.
The sound barrier is an example. You may see a jet and then latter hear the sound from the jet. That does not mean that the jet is not making sound in the now just because we won't hear it until the future. | |
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| Black holes...help!
Posted: 5/30/2007 2:30:37 PM | | Well, Robby - When viewing a star (or the light, therefrom) we are not seeing into the past. The light is present for us in the here and now. The starlight is being emitted from a source from the past. I know - it's sound weird, right:) | |
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| Black holes...help!
Posted: 6/3/2007 12:01:17 PM |
Don't think of Black Holes as holes. They're more like vaccuum cleaners.
Yes!!! I also recently watched a documentary on black holes (spheres) and they are maybe the size of a pea which is why we cannot see it unless using a specific type of light telescope thing (Im not sure what its called) but basically you can see stars and what not being pulled in and sometimes when the black hole is umm shall I say full, it "burps" out a loooooooong trail sometimes a galaxy length of the matter in which its consuming. But now I am left to wander and maybe someone can clarify this for me, because it takes so many light years for stars to reach us so they may no longer exist... Maybe these black holes are no longer here they have already eaten their desired amount. Maybe we are not really here either... Maybe a black hole has already consumed us and we being 3-d creatures cannot comprehend this so we live in a state of mind where we cant let go of the past and choose to live in an ongoing world which has died out eons ago. | |
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| Black holes...help!
Posted: 10/4/2007 10:52:08 PM | | I do not think it as it appears ,yes stars and such are sucked in and sometimes the pressure is reversed as like smoke in a chimney would do when wind and pressure changes outside which is why you see matter exiting a black hole as you described as a burp,but normally as with a chimney,the smoke goes just the one direction.A black hole is nothing like it is said to be,it is as if you are in the eye of a storm where in the middle it is calm compared to its surrounding energy,kind of like the center of a twister,I believe a black hole is actually a gateway to another place I believe it has what could be compared to a current in a river created by the differences in pressure from point A to point B,I also believe that some black holes are an in direction and in other areas of space there are exit holes all created by the pressure differences,like smoke being sucked out of a chimney and it could be argued that the exit is only at certain times,so they are all two way or like a home with opposite windows open,air is drawn in and exited out the other side of the house,it started in the same air pressure and exited in the same air pressure outside,yet had a direction,an in and an out.Perhaps we have never found life out in space because we are not looking in the right areas,or rather we're traveling down the wrong road,I view the black holes as a roadway to another place | |
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| Black holes...help!
Posted: 1/5/2008 12:24:02 AM | Now I see your talking about black hole's. Well i'm not smart on this area but I have thought if your are in a different dimenion that you would be able to use them to travel, just like star gate I guess that's a good way to put it but cause the black shperedoes that, you know make something in to nothing. Then i have something to ask I know it is off topic but:
Is there a area that we have found in space that (how can I say this) spit's out , instead of suck's in? I'll start a post on that if there is one , I wouldn't want to make this post off topic cause of this post.
Well thank's if someone can help it would probley better to just mail me on that..
But I do think that if we lifed in anouther dimesion we could use it for travel. Dimesion. I think Dimesion is the word I want to use, if it's not I'll will come back and make it clear. But I have heard that humen's & Gray's( race of alien, 9month's from us, in there ship's), are into different dimention. Just like ghost(if you believe) or in a different one then us.
Well have a good one. I hope you find your anser man. Sorry for going for tpic. | |
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| Black holes...help!
Posted: 1/5/2008 8:35:01 PM | | Yeah, it's a sphere. Stdied this a bit before with a guy that was trying to take apart newton's theory of relativity. | |
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| Black holes...help!
Posted: 1/5/2008 8:36:37 PM | | But it's not the past we see..... I guess I agree. It's the light from the star traveling into view. It still takes a while to reach earth because it's so far away. | |
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| Black holes...help!
Posted: 1/6/2008 1:25:46 PM | In the "space" taken up by the black hole, is it theorized that this is in effect a singularity? That the nature of it would not conform with the laws of the universe as we know it? Think about it...gravity is caused by mass, at least that is the way it is understood... if a black hole is a singularity where matter and energy (the components of mass) are reduced to nothing...where is the gravity originally coming from? Does a black hole have levels? Like an onion? Each one from the outside to the singularity having more gravity until it too disappears?.. What holds this thing together if there is nothing really there? Or.. is it possible that it becomes interdimensional at the vanishing point? If black holes really do "suck up" matter and energy would there not be a way to measure this? It would mean that there is less matter and energy in our universe than there was at the big bang, unless somewhere this matter and energy is being replaced or re-entering the universe. Which would also suggest that matter and energy (our common 3-d types anyway) are somehow interchangeable between dimension. Or am I completely not getting this?
Is it possible that the mysterious "dark matter" has a balancing effect on a black hole? Or is it also subject to the gravity? Also... I understand dimensions... 1 dimensional, 2-dimensional, 3 dimensional... and I believe "velocity" of matter and energy causes the fourth dimension of "time". But my mind can not grasp any dimension beyond this, yet according to string theory there may be 11 or more dimensions. Are there any descriptions of what these might be? Or is it something that has to be described in purely mathematical terms?
Just some thoughts | |
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| Black holes...help!
Posted: 1/6/2008 1:31:09 PM | hey caballero: "Who's saying that? That'd be like saying we hear lightning as soon as it strikes rather than having to wait for the sound to get to us. The same applies to light. We won't see something until the light from it reaches us."
So if we build a star ship and travel towards those distant points of light at the speed of light, are we traveling into the past or into the future? lol | |
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| Black holes...help!
Posted: 1/6/2008 2:50:34 PM | to Ravenstar:
The way I understand it, black holes are not where matter and energy are reduced to nothing. Matter and energy are compressed to a point of infinite density (i.e. the singularity), and that is definitely not nothing-- It still has mass, which is why it still has gravity.
Remember a black hole still has mass and spin, just like a regular star. A black hole weighing 20 solar masses exerts exactly the same gravitation as a Main Sequence 20-solar-mass star, and objects orbiting them obey the same orbital mechanics. Falling into a 20-solar-mass Main Sequence star will kill you just as dead as falling into a 20-solar-mass black hole. :-)
A star needs a certain amount of mass to form a black hole at the end of its life. Not heavy enough, the star can't collapse enough to compress down to a singularity. Those smaller stars become neutron stars or white dwarves instead, depending on how massive they are.
to peacelover61:
Moving at the speed of light makes time expand (i.e. slow down) compared to the time observed by someone travelling at a slower speed. Time will still go forward, but slower.
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| Black holes...help!
Posted: 1/8/2008 9:33:38 PM | Remember, it's all quite difficult to elaborate on the "true" nature of Black Holes. The point at which the singularity exists is basically the point when General Relativity breaks down. I.e. we need some "new" Physics to describe these quantum singularities (which is a more apt name for a black hole).
If you look at some of the theories flying around in Superstring and M-Theory, singularities are postulated to be simply strings with their own "unique" black hole vibration.
Anyway, despite a lot of indirect evidence (but hopefully direct evidence of massive gravitational effects using the upcoming LIGO detector), even if we found a black hole, it would be very difficult getting direct info from it by sending some kind of probe.
Basically, if you view space-time as a huge rubber sheet, and placed an immensely small, but immensely heavy ball at the centre of the rubber sheet, the ball, if it’s heavy enough, will continually "sink" through that rubber sheet... Indeed it would continually sink for ever (if it was heavy enough).
Hence, since this rubber sheet of space-time is sooo stretched and warped around that immensely heavy weight, then that means time also gets stretched too. Hence, you'll watch your probe falling into the event horizon (the "no return" region from which light cannot escape) and because space-time is sooo warped, it would take an INFINITE amount of time, relative to you, for your probe to reach the horizon.
So black holes are very weird indeed. And it's gonna take some time (and some fancy Physics and technology) before they give up their secrets. Because of their nature to literally "conceal" themselves in these event horizons, some scientists have postulated that this is how the Universe gives "birth" to baby universes LOL.
Mind blowing stuff! | |
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| Black holes...help!
Posted: 1/9/2008 1:45:51 AM | Black holes are the garbage dumps of space. They take in matter, crush it up and from the edges of no return, comes a stream of radiation.
Black holes are like the 3 Dimensional corners of space. (mmmmm hyperspheres!) Where space is incredibly bent and curved.
They give space its shape.
The only reason they are depicted as spherical is because at that point of the event horizon (the schwarzchild radius i think its called) that is where light cannot escape (the escape velocity of a black hole is greater than light) so its depicted as a sphere of blackness surrounded by hot matter. At the center of the black hole, is a singularity which is basically a point that has no space or time, where all space in between things are removed.
General relativity has a mathematical property that allows WHITE HOLES. They are the opposite of black holes or time reversed black holes. A black hole is a region of space from which nothing can escape, the time-reversed version of a black hole is a region of space into which nothing can fall.
In fact, just as a black hole can only suck things in, a white hole can only spit things out.
White holes are perfectly valid in relativity but that doesn't mean they exist.
On the same token, one may try to argue that a perfect example of a white hole is what produced our universe. :)
Nice thought eh?? Black holes suck in and break down all matter and white holes spit out and create universes, which make black holes, and they suck in all matter, and white holes... welll you know :P
This would give our universe a multi verse feel.
>>>I don;t get the collapsing in on itself. Once it collapses in on itself, what is on the other side of all that sucking, where is the matter that is getting sucked going after it gets sucked?
A way to imagine the collapse.
Think of our solar system
There is a massive sun and there are planets in orbit, that are far from the Sun. Think about all the space that is between the orbits (the earth is 93 million miles from the sun)
Most of the matter is contained within the sun and there is massive amounts of space between the orbits of the planets.
What would happen if you took all that space away?? And COLLAPSE the orbits of the planets? Bring them closer to the sun?? They would crash in to each other and in to the sun, leaving only a really dense object that had sucked up all the planets and made it apart of the sun.
The sun at the end of it when all the space between the planets, is actually the singularity in a black hole. A point where everything collects and gets squished.
That is basically what a black hole is... a place where all the space between things has been taken out... it goes further in to that, (infinite density) but as hammy hamster said... thats another story :)
>>> Recently he changed his theory that black holes convert matter to enegry to allow it to escape out the other side...
There is no "other side" but as above, you could think of a white hole as the time reversed "other side" of a black hole.
Here is a thought. We found galaxies when we looked out in space and also found these things called... QUASARS. What quasars turned out to be, is us looking at a black hole or the center of a galaxy HEAD ON, right in the stream of the radiation release. We are happening to pass through the stream of what ever is radiating from the center our of galaxy in 2012, which is why the Mayans signified it.
It has to do with the 26,000 GREAT YEAR of our precession.
But again... as hammy hamster said.. thats another story :D
GHPiNK | |
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| Black holes...help!
Posted: 1/9/2008 8:42:44 AM |
The French mathematician LaPlace first speculated about the existence of an object so compact that the escape speed would be greater than the speed of light. The first relativistic calculation was performed by Karl Schwarzschild (1916) shortly after Einstein published his theory. Curiously, Schwarzschild's result is the same as that of LaPlace.
So, we look up Laplace at Wikipedia: http://en.wikipedia.org/wiki/Pierre-Simon_Laplace
And we find that indeed, he was publishing this theory in the early 1800s.
This is neither common knowledge nor would be naturally expect a hypothesis of blackhole behavior to precede Relativity Theory of the Twentieth century by nearly a hundred years.
I am impressed with Auggies mention of LaPlace
Laplace is an underrated mathematician. He is pretty much everywhere in classical physics and he can be easily found in quantum mechanics. Another interesting thing he discovered is that he calculated that the moon must have a not perfectly balanced mass from the tiny wobbles of its orbit. He actually calculated the excentricity of the mass in the 18th century. It turned out to he was accurate when the russians sent probes around the moon to measure the mass. | |
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| Black holes...help!
Posted: 1/9/2008 5:39:49 PM | The sun at the end of it when all the space between the planets, is actually the singularity in a black hole. A point where everything collects and gets squished.
Our sun will not become a Black hole. it doesn't contain enough mass to become a Black hole or even a Neutron Star. It takes atleast 3 solar mass stars (stars three times more massive then our sun)to eventually collapse into a Black Hole. It takes a star with the mass or 1.4 to 3 of our suns, to collapse into into a Neutron Star. Only Super-Heavyweight Blue Giant stars and other super heavyweight stars will eventually become a Black hole after their suns grow immensily into a Red Giant, about a hundred times their previous size, and then these stars will explode in a supernova and then their cores will ultimately collapes into either a Neutron star or a Black hole depending on the mass of the star. The most mssive stars will become Black holes eventually.
But our sun is only medium size in comparison. Eventually our sun will also grow and swell up immensily into a Red Giant, about a hundred or more times it's current size, but then, instead of the sun going supernovea, it will shed off it's outer layers, and the gas will travel far out into space, and eventually the core of our sun after its outer layers have been shed off, the core, will become a White Dwarf Star. The outer layers of our sun that have been shed off will eventually become a Planetary Nebula with the White Dwarfe star (the core remnant of our sun) in the center. | |
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| Black holes...help!
Posted: 1/9/2008 6:16:22 PM | The only way our Sun could become a Black Hole, is to somehow artificially condense its entire mass, into the size of a small marble.
Black Holes are more about extreme (theoretically infinite) densities, and such densities can be brought about in a number of ways, as eloquently described the previous poster. Also, sub-atomic black holes are postulated to exist too, but due to their size, only exists for brief moments of time. | |
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| Black holes...help!
Posted: 1/11/2008 9:28:57 PM | >> Our sun will not become a Black hole. i
I never said it would.
I was giving an analogy of what would happen if you took out the space between things and I used our solar system as an example :)
The final point I was making was if the solar system was like a black hole, the sun would be the singularity.
I guess maybe I didnt write that one good enough :) ha ha sorry! | |
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| Black holes...help!
Posted: 1/11/2008 10:02:22 PM |
Remember a black hole still has mass and spin, just like a regular star.
There is some interesting conjecture regarding black holes and fundamental particles.
Black holes can be defined using their three basic properties: spin, mass and electric charge. These are the only things which make black holes different from each other.
Likewise, fundamental particles are also defined by these same three properties. Some people have speculated there may be a deep connection between the two. String theorist Brian Greene has even suggested that electrons may actually be microscopic black holes. He covers it in his book, "The Elegant Universe", which is quite a good read, despite my scepticism regarding String Theory.
Wikipedia explains it better than I can:
http://en.wikipedia.org/wiki/Black_hole_electron | |
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| Black holes...help!
Posted: 1/12/2008 9:24:01 AM | Comparative gravities in various cities around the world
The table below shows the gravitational acceleration in various cities around the world.[4]
Amsterdam 9.813 m/s² Istanbul 9.808 m/s² Paris 9.809 m/s²
Athens 9.807 m/s² Havana 9.788 m/s² Rio de Janeiro 9.788 m/s²
Auckland, NZ 9.799 m/s² Helsinki 9.819 m/s² Rome 9.803 m/s²
Bangkok 9.783 m/s² Kuwait 9.793 m/s² San Francisco 9.800 m/s²
Brussels 9.811 m/s² Lisbon 9.801 m/s² Singapore 9.781 m/s²
Buenos Aires 9.797 m/s² London 9.812 m/s² Stockholm 9.818 m/s²
Calcutta 9.788 m/s² Los Angeles 9.796 m/s² Sydney 9.797 m/s²
Cape Town 9.796 m/s² Madrid 9.800 m/s² Taipei 9.790 m/s²
Chicago 9.803 m/s² Manila 9.784 m/s² Tokyo 9.798 m/s²
Copenhagen 9.815 m/s² Mexico City 9.779 m/s² Vancouver, BC 9.809 m/s²
Nicosia 9.797 m/s² New York 9.802 m/s² Washington, DC 9.801 m/s²
Jakarta 9.781 m/s² Oslo 9.819 m/s² Wellington, NZ 9.803 m/s²
Frankfurt 9.810 m/s² Ottawa 9.806 m/s² Zurich 9.807 m/s²
as you see, your starting point is FALSE!
If I am on earth...anywhere on earth, the gravitational pull would be the same.whether in China, Australia or the Americas. | |
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| Black holes...help!
Posted: 2/20/2008 11:25:01 AM | Interesting subject here.
One of the things I love in life is how we keep learning more. Just like the other day they discovered a new form of life! One that was unknown previously! On our own planet! Same old same old.
We so often think we know what's going on on this spinning globe and we are so often wrong, due to allowing our beliefs to influence our vision, imo.
At any rate, there is now conclusive evidence, contrary to previous beliefs, that each galaxy in the universe has a massive black hole. And recent studies indicate that black holes have a cycle of life in and of themselves, sometimes taking things in at slower rates than others. Some are more difficult to see than others, for example the one in the Milky Way, our galaxy, can't even be seen by the best telescopes on the planet or orbiting it. Astronomers only know of it's existence due to the gravitational pull on objects in the nearest solar system and comets near it, noting how their orbits are changing.
Hawkings' view that what goes into a black hole gets converted to energy is certainly plausible, imo, but so is the idea that a black hole would take something to another part of the universe, perhaps popping out of some wormhole some where else.
There are numerous things that no one has explained, or even studied, yet.
Want to worry about a black hole? Worry about the one in our own galaxy. 
rt2 | |
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| Black holes...help!
Posted: 2/20/2008 2:23:57 PM | Sorry, Peace, I missed your post.
So if we build a star ship and travel towards those distant points of light at the speed of light, are we traveling into the past or into the future? lol
If we were to travel to a distant star at the speed of light, you could think of it as traveling into the future. But you have to really look at it to see if what's happening fits your definition of time traveling. Really we're all time traveling all the time, but in only one direction, into the future.
But here's what would happen if it were possible to travel to a star, say, 100,000 light years away at the speed of light (for simplicity, I'm assuming instant acceleration to that speed and instant deceleration at the end of the trip). At light speed all internal processes would stop completely, so we wouldn't age and we wouldn't be capable of experiencing the trip at all. We also wouldn't be able to do anything to make ourself stop. But let's say there was a way around that last bit. Once we got there, to those we left behind, 100,000 years would have passed and we would see the star pretty much as it exists in it's current time. Well, probably some seconds or minutes in the past because we'd need some distance between us and the star so as to not be burnt to a crisp. Therefor, the light we took in would have left the star at some point in the recent past, showing us what the star was like at that time. This, btw, would be an image of the star 200,000 years "later" than what we'd been looking at on Earth (because it took 100k years to get there and the image we'd been looking at while on Earth was already 100k years old).
Here's the cool part. If we then left this star, headed back toward the Earth at the speed of light, we would again not experience the trip or age. AND the star we left would also seem to have not aged. That's because the light (think image) of that star as it existed when we left traveled right along with us at the same speed, so that's what we'd see when we arrived back at Earth (not implying the image would be the same size and detail, because only the light aimed right at the Earth would be with us). Earth, however, would have aged another 100,000 years, so it'd be (from our perspective) 200,000 years into the future as compared to when we left it.
I also think some of the confusion comes from imagining that we can see a "time". We do not see time. We see light, images, all of them created at some point in the past (whether extremely recent--look at your hand for a REALLY recent image, or old--look at the stars). | |
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| Black holes...help!
Posted: 2/20/2008 4:12:28 PM | Are we not able to create mini-black holes in particle accelorators?
I wonder... I have read a quantum physics related theory that information is available instantaneously everywhere. So that theoretically we could create quantum telescopes, position them far away from the earth and be able to peer into the past (not our past but the future's past...  )
Of course the actual quantum theory is much prosaic then this (having to do with electrons and their stranger than fiction type of behavior) | |
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| Black holes...help!
Posted: 6/30/2008 2:23:57 PM | | A quantum singularity is not simply a super dense sphere with an escape velocity exceeding that of light. The curvature of space around the singularity is such that when one passes the event horizon, there is no path that leads away from it. This path can correctly be referred to as a "hole" just as if one were to go outside and dig 10 feet into the ground. If you were to fall 10 feet through the path leading to the bottom of that hole you'd eventually hit the bottom...yes. The opening and path together are no less a hole though. The same is true for the black hole. | |
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| Black holes...help!
Posted: 7/1/2008 5:13:49 PM | "Black holes are a theory, subject to be reinvented at any time."
Ummm, not exactly. In fact, there is a lot of indirect evidence that goes a long way to actually proving the existence of blackholes, even if they have not been observed directly. Cygnus X-1, a strong x-ray and radio source in Cygnus, was observed and showed a star circling an invisible companion. However, judging from the speed it orbited, it could only be a black hole.
M87 in the Coma Virgo cluster, particularly matter at its centre swirling at a speed too great to be anything else. Then there's it's giant jet. Matter in our own galaxy's core. Quasars. Oh, the list goes on and on. | |
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