| Black holes...help!
Posted: 4/14/2007 3:21:45 PM | | The current evidence seems to support the theory that these jets are not made up of material coming back out of the black hole but rather that material that has not yet gone beyond the event horizon is being thrown outward by magnetic fields produced by quickly spinning black holes and/or their accretion disks. | |
|
| Black holes...help!
Posted: 4/14/2007 3:27:57 PM |
The current evidence seems to support the theory that these jets are not made up of material coming back out of the black hole but rather that material that has not yet gone beyond the event horizon is being thrown outward by magnetic fields produced by quickly spinning black holes and/or their accretion disks.
What kind of magnetic field are you talking about? wouldn't the magnetic field pull it towards the black hole? | |
|
| Black holes...help!
Posted: 4/16/2007 3:53:04 AM | Living-it-up, I enjoyed yours and everyones theorys and discussions on black holes. I would like to try and add a little to the conversation if I could.
Living, you gave a pretty good description of a black hole in msg 75, however there are a few other things to think about.
If we talk about the big bang theory (something for which I don’t agree with entirely) it suggests that all of the matter in the universe came from a singularity or a central point or the heart of a black hole, this means everything, matter, dark matter, energy and even space itself. This is supported by the observations that we have found the universe is expanding. (To go beyond that the current best theory to describe that is string theory. In which large membranes that exist in another dimension intermittently touch one another to give rise to the singularity that created our universe.)
Now, if all of the matter in the universe came from one central point or singularity, what velocity is needed for all of that matter to exit the singularity without it all falling back in on itself though the sheer mass of it? The only answer that makes sense is a velocity greater than the speed of light. This would mean that the speed of light is not a constant in the universe, (Look up variable speed of light)
This is one of the problems behind unified theory and the explanation of a singularity. Another theory is variable gravity which may also help to eventually explain how all that matter was able to achieve escape velocity. In any case, all of the laws of physics currently break down when it comes to singularities. This is the reason that unified theory is the holy grail when it comes to physics. The thinking is if you can find a way to link electromagnetism, gravity, nuclear strong force and nuclear weak force into one generalized theory of everything, we may understand not only a black hole and its singularity, but the creation of the universe as well.
We have confirmed though observation that there are black holes, in fact there seems to be a black hole at the center of each galaxy, and it seems as if black holes have an integral part in the formation and life of a galaxy.
But does the singularity bleed matter off into another space time dimension? Or is it merely an entrance to a worm hole that deposits matter into another location in the universe, no one knows. But we are beginning to see that the absorption rate of a singularity is not fast enough to eat all of the matter in a black hole or if it even does at all. We do know that black holes can and do get supper massive, containing millions of times the mass of our own sun. We can measure this by observing the velocity and the orbital trajectories of the stars that orbit the black holes. In fact this is how we know there are black holes, because of observations like this.
I hope this helps, if nothing else I think I gave you some more material to look up on the net, enjoy... | |
|
| Black holes...help!
Posted: 4/16/2007 4:46:57 AM | | Oh, almost forgot, also try looking up "M" theory. Just google all the stuff I talked about and you will have your hands full with junk that will blow your mind. Have fun trying to figure it all out.... | |
|
| Black holes...help!
Posted: 4/16/2007 9:45:46 AM | What kind of magnetic field are you talking about? wouldn't the magnetic field pull it towards the black hole?
Depending on relative charges, you can get either attraction or repulsion. Think of two strong magnets held in each hand. When you try to force two positive poles together, they resist. The same happens when you try to force two negative poles together. And I know this may sound strange and seem to defy daily subjective experience, but when we physically interact with objects (anything from clapping your hands together to jumping in the air and being stopped by the ground) it is electromagnetic repulsion that insures we don't go through those objects.
Here's an article on space.com giving an idea of just how strong the jets that eject this matter are. Amazing.
http://www.space.com/scienceastronomy/astronomy/blackhole_sim_020130.html | |
|
| Black holes...help!
Posted: 4/16/2007 11:04:56 AM | A few points: First gravity actually isn't perfectly constant everywhere on Earth. The variances are utterly small and beyond unassisted detection but they are there. This would be true of all bodies.
While the term "hole" is not exact here it is also not as inaccurate as it might at first seem. Space itself is curved or bent by the presence of a physical object so there is a hole in a sense. Because a BH rotates up to several times a second, objects will be drawn into its accretion disk along its equator before entering the event horizon--the point where light can no longer escape because escape velocity exceeds the speed of light. This requires quantum mechanics to describe in detail as we are dealing with more then 3-dimentional space.
Also, not everything pulled-in by the BH actually ends-up there, much of it is thrown-off in polar quasars. Imagine trying to fill a dog dish with a fire hose. Also, black holes slowly evaporate over time, bleeding off subatomic particles a few per second. This is the Hawking Radiation that made Steven Hawking a household name. The time scale for this are measured in goggles of years (1o to the 1ooth power).
Goggle "Neil DeGrass Tyson" to find his website. He's an astrophysicist and curator of the Hayden Planetarium in NYC. He is well versed in describing these effects in layman terms. | |
|
| Black holes...help!
Posted: 4/16/2007 12:27:43 PM | Good points Starvartist. Another theory of gravity is that it acts like a wave. For example, if you were to remove the Sun from our solar system the planets would continue to remain in orbit until the lingering effects of gravity dissipated. Plop a new star in the center and the planets would continue their spiral out of the system until the effect of the new gravitational field reached them and brought them back. Something like the ripples in the water after you throw a pebble in but in reverse.
Here on Earth the effects of gravity and light seem instantaneous, but when viewed or measured on a cosmological scale it is quite slow. Take the red shift for example. We can tell distant objects are traveling away from us by observing their spectral image. If the image is shifted toward the red end of the spectrum the object is traveling away, towards the blue and they are traveling closer. The problem is we are observing the light from objects that are 12 billion light years distant, so our information on those objects movement is 12 billion years old. | |
|
| Black holes...help!
Posted: 4/16/2007 4:29:57 PM |
Take the red shift for example. We can tell distant objects are traveling away from us by observing their spectral image. If the image is shifted toward the red end of the spectrum the object is traveling away, towards the blue and they are traveling closer. The problem is we are observing the light from objects that are 12 billion light years distant, so our information on those objects movement is 12 billion years old.
This is correct, but, in case anyone's wondering, red-shifted galaxies are unlikely to have begun moving towards us because the recession of such distant objects from us is mostly due to the expansion of the universe, not their movement through space. | |
|
| Black holes...help!
Posted: 4/16/2007 5:47:50 PM |
I don't think tehre is a singualarity, there is NO EVIDENCE that shows there is a singularity there. There's a lot of mass in a comparatively small space. I am not aware of anyone asserting that an entire black-hole existed in a singular space (presumably the size of a string).
I beleive that Black holes just pull or absorb things in them and they come out the other end, and we can see that they do because when you see those jets flying up on BOTh sides of the Black hole A simple google search would have told you that the jets eminate from the acrition disks, not from beyond the event horizon.
that means when it went into the black hole , it went in there fast due to the black holes immense pull, but when it did and it crossed the actual hole (point of horizan) it just went out the other way. That would require the material in question to be moving faster than the speed of light, which is impossible.
What kind of magnetic field are you talking about? wouldn't the magnetic field pull it towards the black hole? "The magnetic field caused by the moving energized matter moving toward the black hole" and "sometimes yes but often no".
If we talk about the big bang theory (something for which I don’t agree with entirely) it suggests that all of the matter in the universe came from a singularity or a central point or the heart of a black hole That is not what the Big Bang theory says. The Big Bang theory says that spacetime was once much smaller than it is now.
Now, if all of the matter in the universe came from one central point or singularity, what velocity is needed for all of that matter to exit the singularity without it all falling back in on itself though the sheer mass of it? Since the premise is wrong... yadda yadda.
As to the amount of energy invovled in the big bang: Immediately after the big bang the universe was too energetic (hot) for atoms to form. It had to cool down before it was possible to have them.
The only answer that makes sense is a velocity greater than the speed of light. This would mean that the speed of light is not a constant in the universe, (Look up variable speed of light) The speed of light never varies in a vacuum.
But does the singularity bleed matter off into another space time dimension? Or is it merely an entrance to a worm hole that deposits matter into another location in the universe, no one knows. Or, wacky though this may be in regards to a lack of imagining unevidenced universes: Perhaps it's a bunch of matter all in one place attracting other matter with gravity (as matter is wont to do) and thus creating a local gravity so high that the accelleration reaches 180,000mi/s/s
A few points: First gravity actually isn't perfectly constant everywhere on Earth. The variances are utterly small and beyond unassisted detection but they are there. This would be true of all bodies. The reason is that the Earth is not perfectly round and is not uniformly desnse. This would, therefore, be true of all bodies of non-sphereical shape or non-constatnt density.
Good points Starvartist. Another theory of gravity is that it acts like a wave. For example, if you were to remove the Sun from our solar system the planets would continue to remain in orbit until the lingering effects of gravity dissipated. Gravity moves at the speed of light. | |
|
| Black holes...help!
Posted: 4/16/2007 8:47:55 PM | No, hate to burst your bubble jerry, but general relativity does predict a singularity. “M’ theory even less, but unless you wish to tell me you have solved the problem of how matter acted in the inflationary period you cannot say for certain what the speed of light is at that time. What I am trying to deal with is the horizon problem and with information at a distance. Lets look at it another way..
How did the volume of the universe, a hundred billion times smaller than a proton, expand to approximately one hundred million light years across in just 10-32 seconds?
Remember, we are talking about the early early universe, were not even talking about any matter that Einstein agreed with, he hated quantum particle science. Light didn’t even exist at this point, just a bunch of stuff that was going to be matter someday. So the laws of physics, as I said, not only do not apply here they didn’t even exist as we know it. So your cosmic speed limit is safe.
At any rate, when we talk about black holes and singularities, we are talking in turn about big bang as well. That first singularity contained all of the black holes that now exist as well as all matter that we see and beyond. It certainly must go way beyond even our most complicated understanding of current theory. So I am not surprised when we can’t grasp the concept | |
|
| Black holes...help!
Posted: 4/17/2007 3:08:15 PM |
No, hate to burst your bubble jerry, but general relativity does predict a singularity. I was unaware that would burst my bubble. Sounds like a conversation. Given that you don't understand what the big bang theory describes, you'll forgive me if I don't take your word on what any others do.
but unless you wish to tell me you have solved the problem of how matter acted in the inflationary period you cannot say for certain what the speed of light is at that time. Depends on the material it's passing through. Through a vacuum it was 180,000mi/s just like it is now.
How did the volume of the universe, a hundred billion times smaller than a proton, expand to approximately one hundred million light years across in just 10-32 seconds? Why do dolphins live in Igloos? The answer is "they don't".
The universe took, minimally, 50,000,000 years to become 100,000,000 in diameter... more from the perspective of something at the edge of the universe.
Remember, we are talking about the early early universe, were not even talking about any matter that Einstein agreed with, he hated quantum particle science. What makes you believe that Einstein was worried only about matter. As I recall, his original insperation to get into physics was magnetism.
Light didn’t even exist at this point, just a bunch of stuff that was going to be matter someday. Please support "no light"... though it really wouldn't have much effect on me to discover that the energy of the big bang did not exist at light frequencies early in, it would not effect the speed limit.
So the laws of physics, as I said, not only do not apply here they didn’t even exist as we know it. So your cosmic speed limit is safe. Of course the laws of physics applied, as they have always applied since the moment after the big bang an right up to the event horizons of a black hole.
At any rate, when we talk about black holes and singularities, we are talking in turn about big bang as well. No, we are not. A black hole exists within timespace. The big bang was the sudden expansion *of* timespace.
That first singularity contained all of the black holes that now exist as well as all matter that we see and beyond. It certainly must go way beyond even our most complicated understanding of current theory. So I am not surprised when we can’t grasp the concept And yet you think you grasp the concept when you don't know at even the layman level what happened in the big bang? | |
|
| Black holes...help!
Posted: 4/17/2007 7:55:44 PM | Gravity moves at the speed of light.
IT DOES???? Thats news to me. How can gravity move at the speed of light? Only light can move at that speed and we know (atleast I have heard that light speed is constant) how can gravity which is not constant be moving at the speed of light. If it was then anything that is absorbed in gravity would be moving at the speed of light.
For example.... If I fell off my chair here and I fell to the ground ,because of gravity, I would obviously not be falling at the speed of light to the floor LOL LMAO, ....right?? so I don't understand how you can equate Gravity with light. ??
Gravity varies , but the speed of light atleast according to you is constant.
Unless you meant gravity in referance to black holes, then I don't know you may be right then. | |
|
| Black holes...help!
Posted: 4/17/2007 8:26:14 PM |
For example.... If I fell off my chair here and I fell to the ground ,because of gravity, I would obviously not be falling at the speed of light to the floor LOL LMAO, ....right?? so I don't understand how you can equate Gravity with light. ?? lol ever heard of acceleration lmao
I always thought gravity was instantaneous but I admitingly have no idea. :) anyone have references? | |
|
| Black holes...help!
Posted: 4/17/2007 8:46:50 PM |
lol ever heard of acceleration lmao
lol I know....But my point is that light is constant, there is no acceleration, thats my point, in gravity there is. So how can gravity move at light speed it by it's nature it operates differently? | |
|
| Black holes...help!
Posted: 4/17/2007 9:06:15 PM |
So how can gravity move at light speed it by it's nature it operates differently?
Gravity as all elementary forces move at the speed of light in the form of gravitons (waves that perform similar to particles). | |
|
| Black holes...help!
Posted: 4/17/2007 10:21:19 PM |
Gravity moves at the speed of light.
lol ever heard of acceleration lmao
While you are busy laughing at him for not grasping acceleration... we might do the same to you for not grasping Terminal Velocity. That is the maxium speed at wich an object will fall, period. It does take some time to reach that speed and he wont reach it by falling off a chair, but there IS a max speed at wich something will fall... and its a LOT less than the speed of light. | |
|
| Black holes...help!
Posted: 4/18/2007 1:03:59 AM |
While you are busy laughing at him for not grasping acceleration...
I explained what I meant by that in my other post.
we might do the same to you for not grasping Terminal Velocity. That is the maxium speed at wich an object will fall, period. It does take some time to reach that speed and he wont reach it by falling off a chair, but there IS a max speed at wich something will fall... and its a LOT less than the speed of light.
Thanks....point made claer. | |
|
| Black holes...help!
Posted: 4/18/2007 8:41:52 AM | lol dude I didn't even mention terminal velocity...? (as it wasn't really relevant due to the distance involved) and I do grasp it btw.. A humans terminal velocity in the lower elevations of earths atmosphere is around~ 110-130 miles per hour when falling (if i remember correctly) this is due to air resistance
side note: acceleration due to gravity on earth is 9.8 meters per second, per second
but of course this is off topic lol :)
lol I know....But my point is that light is constant, there is no acceleration, thats my point, in gravity there is. So how can gravity move at light speed it by it's nature it operates differently?
while the speed of light is technically a constant the speed of light is not always the speed of a photon -like when traveling through glass or air. the light can be bent or slowed down cause it is being absorbed and re-emitted by atoms in the substance
just cause something operates differently doesn't mean it cant go the same speed
btw light can push things have you heard of a solar sail? its basically a big sail (obviously) that is used to ride the light being emitted from a source such as the sun. this can also work with laser beams.
http://metaresearch.org/cosmology/speed_of_gravity.asp
didn't read the whole thing but i saw some references to faster than light propagation of gravity in there so those intersted may find it intersting
-ima go to sleep mow lol ive been up since yesterday lmao :p | |
|
| Black holes...help!
Posted: 4/19/2007 6:53:42 PM |
How can gravity move at the speed of light? Only light can move at that speed That is, simply put, not true. There are quite a few things that move at the speed of light. Of course, that starts with the entire elecectro-magnetic spectrum (electricity through a superconductor, magnetic force, etc) and includes gravity.
How fast do you think gravity moves and why?
If it was then anything that is absorbed in gravity would be moving at the speed of light. Ahh. So if light is moving at the speed of light than anything pushed by light (say a solar sail) must also be moved at the speed of light?
Your statement is simply wrong. Much like more light in a room makes it brighter, more gravity on an object imparts a greater velocity. The rate of accelleration is just as unrelated to the speed at which gravit moves as the brightness of a room is unrelated to the speed at which light moves.
For example.... If I fell off my chair here and I fell to the ground ,because of gravity, I would obviously not be falling at the speed of light to the floor LOL LMAO, ....right?? I never said that you would.
I always thought gravity was instantaneous but I admitingly have no idea. :) anyone have references? Ones upon a time this was considered true. Relativity predicts that gravity, being an elementry force, will move at the speed of light. Quantum theory (which attempts to explain gravity's comparitive wekaness by having it move through more than 4 dimensions) predicts that it would move faster than light.
The available studies seem to confirm relativity. | |
|
| Black holes...help!
Posted: 4/19/2007 11:29:23 PM |
If I was sucked into a black hole would I still be able to use my x-ray vision to see what I was missing out on back here?
Actually X-rays are emitted from the accretion disk around the black hole, energy (regardless of wavelength) is subject to the same gravitational attraction. As for seeing what's going on outside of the black hole, you wouldn't be able to. Time would have effectively stopped for you because of time dilation, while the rest of the universe would've witnessed your utter annihilation by tidal forces (which, by their frame of reference, would happen very quickly). | |
|
| Black holes...help!
Posted: 4/20/2007 1:47:40 AM | i thought it was the other way around.. one who gets close to a black hole would witness the universe outside accelerate while that person would seem to slow down from a outside perspective.
-but yeah black hole = "no good for health" unless you want to get taller! :) (Right before getting very short [/humor]) | |
|
| Black holes...help!
Posted: 4/20/2007 9:21:28 AM | I think a pertinant point would be this:
The speed of light is NOT constant. It is dependant upon the medium through which it passes. For most purposes, it SEEMS constant.
Since vacuum is a characteristic of space, and space/time is a characteristic of the Universe, it stands to reason that vacuum per se only exists within the universe.
The universe is a product of the Big Bang, and you could argue that the Big Bang and the antecedent singularity ARE the Universe, simply at the earliest stages of its life. My questions would be, "Does vacuum exist at this stage in the universe?" and "If not, and light exists, what medium does it move through? How does this influence its speed? How can space/time be measured at this point? If light is the fastest known speed, does the universe expand at the speed of light, can light leave the universe, or is light bound within it regardless of speed?" To this last question, I would argue that the universe is defined by the presence of light/electromagnetism, and space/time does not exist until illuminated. Simply, light travels faster than matter, and nothingness does not become vacuum until it is part of the universe. This means that the size of the universe could be calculated as a sphere with a radius of C times the age of the universe. This also means we could never leave the universe by travelling less than the speed of light, unless there's a back door to bypass space/time.
This is a bit off topic, but it leads me to wonder about the speed [and general nature] of electromagnetism outside of the normal vacuum of space, in environments such as singularities or black holes. | |
|
| Black holes...help!
Posted: 4/20/2007 12:01:34 PM | This is a bit off topic, but it leads me to wonder about the speed [and general nature] of electromagnetism outside of the normal vacuum of space, in environments such as singularities or black holes.
Thats ON topic, This thread is about black holes, so anything related to it is also ok.
Much like more light in a room makes it brighter, more gravity on an object imparts a greater velocity. The rate of accelleration is just as unrelated to the speed at which gravit moves as the brightness of a room is unrelated to the speed at which light moves.
Can you maybe briefly explain that because I'm not sure I'm getting your drift here. You did mention that light speed is constant ....right?. But with gravity , we have to take into account that there is an acceleration that must take place for something to move faster.
Also even at it's fastest, one user suggested that gravity would STILL not be able to have an object fall at the speed of light , she suggested that after a certain speed the acceleration of an object falling would not go any faster, but yet light from beginning to end always travels the same speed.
Here is what that other user said about this "Terminal Velocity"
we might do the same to you for not grasping Terminal Velocity. That is the maxium speed at wich an object will fall, period. It does take some time to reach that speed and he wont reach it by falling off a chair, but there IS a max speed at wich something will fall... and its a LOT less than the speed of light.
| |
|
| Black holes...help!
Posted: 4/20/2007 12:35:22 PM | To address the last two posts:
In the very early universe, there was no light. The photons were "locked up" by what would later become atoms.
And think about the difference between the speed of gravity and its pull like this:
Imagine, say, a baseball floating in an area of otherwise empty space. Now (not that this would happen) let's say suddenly a star pops into existence one light year away from the baseball. The gravitational influence of the star would begin spreading at the speed of light. The baseball would not be pulled towards the star until the star had been there for a year, at which point it would begin to accelerate at a rate determined by mass of the star, but the baseball would never reach the speed of light. The star's area of influence expands at the speed of light, it does not cause matter within that area of influence to move at the speed of light. | |
|
| Black holes...help!
Posted: 4/20/2007 12:41:56 PM | | ^^So really gravity and the speed of light are to different things afterall. | |
|
Home
login 
