View Full Version : Big Bang really necessary?
employee #416
Aug9-04, 02:48 AM
Hey, everyone, this is my first thread on this site.
I was thinking about the big bang. The big bang is noted as an explosion from a primeval atom. When this atom exploded, matter and energy scattered everywhere. From this explsion, space-time itself was created.
I find it hard to accept this theory. If this atom was said to give offspring to space-time, how could the singularity exist? What came before this singularity? How was it's existance brought up?
Gravity is an issue that blurs this concept. Gravitational forces get stronger as density increases. The singularity was a non-volumetric point that contained all of the matter (visible and not visible) in our universe today. This gave it finite density. Finite density would lead catastrophic gravitational effects. How could this singularity explode outwards, when the gravitational pull towards it were so great? One might counter this by saying the big bang gave offspring to the four fundamental fources which includes gravity, so there was no gravitational pull towards this singularity. If you counter with that, how was this atom held together, if gravity did not exist.
These are just a couple of questions I had. If you can answer, I'd be happy. I'm also trying to make a physics site, so your answers would help me out greatly.
I appreciate your help.
-employee #416
I happen to think what would be surrounding the singularity prior to the big bang? It would have to be Nothing (colorless, spaceless, timeless)... Infinite, time, space, color, all laws of physics would not exist until after the expansion..What about Multiverses did they have big bangs too? Then where did space come from for these singularities to dwell?
employee #416
Aug9-04, 04:12 AM
How can there be nothing? Space is not nothing; space is something. Multiverses are not really proven to exist. Oh, how could this big bang be seated in nothing? There had to have been something to harness it.
employee #416
Aug9-04, 04:14 AM
I just need help on this topic, so I can put it on my website. I don't want to put it on there and not fully comprehend it.
The Big Bang theory is a religion. Its adherents defend it as such. I have had papers that question the big bang theory rejected by reviewers citing that the papers were too dangerous to publish. An idea can only be dangerous to a faith.
I presently favor the Photon Theory (http://photontheory.com/) of matter, and the rules of that theory would not permit there to be singularities, and certainly no Big Bang.
da_willem
Aug9-04, 06:19 AM
The big bang is noted as an explosion from a primeval atom
what do you mean by a primeval atom (you cannot mean a normal atom)?
The singularity was a non-volumetric point that contained all of the matter (visible and not visible) in our universe today. This gave it finite density.
If you put a finite amount of mass in a infinitesimal point you get an infinite density.
russ_watters
Aug9-04, 08:18 AM
If the universe is expanding, then at some time in the past, all matter was at the same point. The universe appears to be expanding. Pretty simple, really.
i think as well that IF there are black holes in the center of our galaxy then why would not the big bang represent a huge blackhole that never exploded,since gravity would be enormous,how does the primordial mass release it's self?
and apparently 15 billion years is not enough time for the universe to organize it's self into galaxies and superclusters.
just some of the arguments i have come across against the big bang theory.
If the universe is expanding, then at some time in the past, all matter was at the same point. The universe appears to be expanding. Pretty simple, really.
Then where would this point be? And where are we in relationship to it? It would perhaps seem a pretty simple calculation.
Then where would this point be? And where are we in relationship to it? It would perhaps seem a pretty simple calculation.
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there is no way to tell,thats why there is no definitive calculation done by now.the theory(big bang) is used to explain the universe more out of tradition than being truly a good theory.
Gravity causes a red shift in the wavelength of light; I wonder what percentage of the observed red shift in the light from distant galaxies is due to gravity taking also into account dark-matter gravity.
Keep on chuggin !!
Vern
Gravity causes a red shift in the wavelength of light; I wonder what percentage of the observed red shift in the light from distant galaxies is due to gravity taking also into account dark-matter gravity.
Keep on chuggin !!
Vern
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according to Halton Arp red shift is the production of matter and that the older, the lesser the red shift,just a perspective!!
da_willem
Aug9-04, 01:31 PM
Then where would this point be? And where are we in relationship to it? It would perhaps seem a pretty simple calculation.
Space itself expanded (and still does!). So the point itself expanded to become our universe. So that point is everywhere!
Space itself expanded (and still does!). So the point itself expanded to become our universe. So that point is everywhere!
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so why does not this point cancel it's self? if looking from one point,at the extreme optical range(far)from extreme closeness(us). and thus create a situation of non-expansion.?
the bride
Aug9-04, 02:14 PM
i think the universe is infinite. i wanted to know if anyone else thinks like me.. this is my first post and i'm so EXCITED!!! also.. i don't believe black holes exist.. and i think the whole theory of the big bang is wrong... what does anyone else think???
russ_watters
Aug9-04, 02:26 PM
Then where would this point be? And where are we in relationship to it? It would perhaps seem a pretty simple calculation. If the universe itself is expanding (as opposed to the galaxies moving apart from an explosion), then there is no central point. The Big Bang happened everywhere at once. This is what our observations suggest. i think the universe is infinite. i wanted to know if anyone else thinks like me.. It very well may be infinite. i don't believe black holes exist. 15 years ago, it may have been a matter of belief (or rather, prediction), but today it isn't: several have been found.
the bride
Aug9-04, 02:34 PM
maybe those aren't really black holes... perhaps those "black holes" are just neutron stars spinning really fast. astronomers can't actually "see" what is going on around the vicinity of a suspected "black hole", so who knows what is it they are classifying as a black hole. have they found black holes in between galaxies? i know there are intergalactic stars, so shouldn't there be intergalactic black holes?
i think the universe is infinite. i wanted to know if anyone else thinks like me.. this is my first post and i'm so EXCITED!!! also.. i don't believe black holes exist.. and i think the whole theory of the big bang is wrong... what does anyone else think???
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no doubt, the big bang is wrong,there are just to many arguments against,there are many theories and problems that question its validity. i suggest being open to other therories,right or wrong but by piecing together one therory to another i'm sure a better theory will come forth.
There's the point, that isn't explained.
The nothing that preceeded it, that isn't explained.
The nothing it's in, that isn't explained.
The point and the space expanding into what, that isn't explained.
The big bang theory, explains less than nothing.
An infinite universe, both in time and space, means it's always existed and it isn't contained within anything... except time and space.
But time and space are relative concepts.
Time needs to start... and space is a lack of something.
Neither one can exist before something else exists.
The point... which we can't seem to explain.
[QUOTE=russ_watters]If the universe itself is expanding (as opposed to the galaxies moving apart from an explosion), then there is no central point. The Big Bang happened everywhere at once.
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so why the clumps of galaxies,superclusters?
and why the small time line? does this make sense? if so why?
There's the point, that isn't explained.
The nothing that preceeded it, that isn't explained.
The nothing it's in, that isn't explained.
The point and the space expanding into what, that isn't explained.
The big bang theory, explains less than nothing.
An infinite universe, both in time and space, means it's always existed and it isn't contained within anything... except time and space.
But time and space are relative concepts.
Time needs to start... and space is a lack of something.
Neither one can exist before something else exists.
The point... which we can't seem to explain.
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exactly, the problem!!
several have been found!? i which direction is the blackhole revolving(Canada or Australia perspective,since there is no observable difference between either) interesting isn't it?
russ_watters
Aug9-04, 03:34 PM
maybe those aren't really black holes... perhaps those "black holes" are just neutron stars spinning really fast. astronomers can't actually "see" what is going on around the vicinity of a suspected "black hole", so who knows what is it they are classifying as a black hole.[emphasis added] That's precisely the point: If they were neutron stars, or anything other than a black hole, they would be easily identifiable as such. Since they behave precisely as predicted, they are almost by definition, black holes.
Imagine scientists predicted the existence of an animal with a flat bill, feathers, and webbed feet that made a quacking sound - and then found one. Are you really going to tell me it could be an elephant? have they found black holes in between galaxies? i know there are intergalactic stars, so shouldn't there be intergalactic black holes? Since black holes can only be detected through their effects on surrounding objects, its unsurprising we haven't found any anywhere else but near other objects. i suggest being open to other therories I suggest being open to all theories - including existing ones. so why the clumps of galaxies,superclusters? Tiny perturbations can create such things: computer modeling/simulation has produced models remarkably similar to the way the universe looks today. and why the small time line? does this make sense? if so why? What is your issue with the timeline? And what does it making sense have to do with anything? The universe need not conform itself to your idea of what makes sense. i which direction is the blackhole revolving(Canada or Australia perspective,since there is no observable difference between either) interesting isn't it? Could you rephrase? That's not a sentence. There's the point, that isn't explained..... Rather unsatisfying, isn't it. To paraphrase an old saying - its the worst theory, except for all the others. Perhaps the answers you are looking for could better be found in other aspects of human knowledge. Science isn't "it."An infinite universe, both in time and space, means it's always existed and it isn't contained within anything... except time and space. Not necessarily - a ray, for example has an origin - a beginning, but no end.
If the universe is infinite, then all of its parts are infinite. Perhaps it is, but if multiverses do exist then this universe is finite, or perhaps I'm thinking of it wrong. If space and time are infinite, then something is wrong with the decaying process. You would have to assume that space and time are transposable. Perhaps Space is boundless, like Einstein stated. Like Earth, you can go in any direction and return to where you began. Neither Space or Time have to be finite (have a beginning), though it would make a lot of sense. Everything else we know has a beginning. Then again, everything else we know had a beginning before its beginning. So perhaps the universe is infinite in the actions caused to create the universe (big bang, and prior to). If we do not know why Existence is, then we cannot argue we know any truth. I am not speaking of religion, just how the human brain perceives the universe, and our system of mathematics, etc.
the bride
Aug9-04, 04:17 PM
russ, what if astronomers are confusing pulsars, weird star explosions, etc. with black holes?? don't astronomers look for x-ray jets as a way to identify black holes? and the question still remains: are there intergalactic black holes?? another thing.. russ do you view an explosion and a ray as the same thing? when i think of an explosion, even in space, it can continue on forever, but it still has an "end" (place where the explosion hasn't reached yet). wouldn't the universe be the same? then this really gets interesting because there is supposed to be nothing outside the universe. i also find it interesting that something as chaotic as an explosion can produce things that are so organized like galaxies and solar systems... i dunno i just think that's a little weird..
That's precisely the point: If they were neutron stars, or anything other than a black hole, they would be easily identifiable as such. Since they behave precisely as predicted, they are almost by definition, black holes.
I do believe in black holes, but I have to say there is no irrefutable evidence of there existence. What we see are disks of matter falling into a massive object, we have yet to see the "black" center. There are theories that predict equally massive (not black holes) that could easily create swirls of gas around them and look just as these disks do. Take for examplet Yilmaz variant of General Relativity which predicts that black holes do not exist. I don't necsisarily agree with any of those theories, I'm just saying it is still under debate.
the bride
Aug9-04, 04:33 PM
Gravity is an issue that blurs this concept. Gravitational forces get stronger as density increases. The singularity was a non-volumetric point that contained all of the matter (visible and not visible) in our universe today. This gave it finite density. Finite density would lead catastrophic gravitational effects. How could this singularity explode outwards, when the gravitational pull towards it were so great? One might counter this by saying the big bang gave offspring to the four fundamental fources which includes gravity, so there was no gravitational pull towards this singularity. If you counter with that, how was this atom held together, if gravity did not exist.
oh neato!! this is a really good point. maybe there was a gravitational force, but not like one we imagine. i know what einstein says about space-time curvature and gravity, so what was going on in that singularity? did space-time exist in it? or was space-time produced by the explosion??
the bride
Aug9-04, 04:36 PM
There are theories that predict equally massive (not black holes) that could easily create swirls of gas around them and look just as these disks do.
neutron stars and white dwarfs supposedly form accretion disks around them... and i know that white dwarfs aren't that massive, neutron stars are like 2 solar masses, but i know they are really dense. i think density has a lot to do with gravity.
russ_watters
Aug9-04, 04:41 PM
russ, what if astronomers are confusing pulsars, weird star explosions, etc. with black holes?? Pulsars and black holes are different and look different. They can't be confused with each other. don't astronomers look for x-ray jets as a way to identify black holes? Yes, among other things, such as gravitational influence. and the question still remains: are there intergalactic black holes?? Intergalactic black holes might help with the dark matter issue, but they aren't pertinent to the question of whether black holes exist.
another thing.. russ do you view an explosion and a ray as the same thing? when i think of an explosion, even in space, it can continue on forever, but it still has an "end" (place where the explosion hasn't reached yet). wouldn't the universe be the same? An particle in an explosion in space would travel in a ray, but that was just an example - the Big Bang was not an explosion. That's a common misconception. There are theories that predict equally massive (not black holes) that could easily create swirls of gas around them and look just as these disks do. Take for examplet Yilmaz variant of General Relativity which predicts that black holes do not exist. I don't necsisarily agree with any of those theories, I'm just saying it is still under debate. Is there really much consideration of these ideas within the scientific community? It was my perception that no alternates are really considered to be viable by consensus.
neutron stars and white dwarfs supposedly form accretion disks around them... and i know that white dwarfs aren't that massive, neutron stars are like 2 solar masses, but i know they are really dense. i think density has a lot to do with gravity.
Unlikely, if so much mass was falling into a neutron star then by current relativity it would collapse into a black hole quite soon.
Singularities only exist mathematically. There is no observational evidence black holes, or the big bang singularity, are infinitely dense. Theorists are currently leaning toward finite density. The Planck density is an attractive alternative to infinite density.
employee #416
Aug9-04, 08:36 PM
what do you mean by a primeval atom (you cannot mean a normal atom)?
Primeval atom simply means the first atom. The big bang was theorized to be the explosion of the first atom to ever exist.
Space itself expanded (and still does!). So the point itself expanded to become our universe. So that point is everywhere!
There is no concrete evidence that space is expanding.
russ_watters, your ponits are being countered with great arguements. I'm leaning towards the side of them not existing now.
Since black holes can only be detected through their effects on surrounding objects, its unsurprising we haven't found any anywhere else but near other objects.
I think that is the point that bride is trying to make.
Pulsars and black holes are different and look different.
So, what visible characteristics of black holes make them differ from the visible characteristics of pulsars? I thought black holes were not visible, so how can they "look different" than pulsars. Unless, of course, you are referring to the outer region of the two.
There is no concrete evidence that space is expanding.That assertion is false.
russ_watters, your ponits are being countered with great arguements. I'm leaning towards the side of them not existing now. There is overwhelming evidence his points are correct.
what visible characteristics of black holes make them differ from the visible characteristics of pulsars? They are far more massive than a neutron star can possibly be.
I thought black holes were not visible, so how can they "look different" than pulsars. Unless, of course, you are referring to the outer region of the two. In a number of ways.
employee #416
Aug9-04, 11:56 PM
That assertion is false.
Vern explained that the universe could very well not be expanding. The evidence they have so far are not concrete. If so, can you provide me a link to where they are 100% sure the universe is expanding and provide valid evidence to back this claim up?
More massive objects do not mean they are visibly different. Black holes are very small. How are they visibly different just by being more massive? Black holes have not be observed directly. Only through indirect observations. So to say they are visually different from pulsars is inaccurate. Maybe they look the same, but they are much more compact?
What we see around black holes is what is happening through interactions at the event horizon. This is not the black hole itself.
Thanks to everyone for your replies. When I get done with my site, I'll provide link. I'll have a number of quotes from you...if thats ok?
Chronos
Aug10-04, 12:35 AM
Vern explained that the universe could very well not be expanding. The evidence they have so far are not concrete. If so, can you provide me a link to where they are 100% sure the universe is expanding and provide valid evidence to back this claim up?
No one is 100% sure of anything. Most rational people fall back to the preponderance of evidence. Start here for the 'preponderance of evidence' that the universe is expanding.
http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/ExpandUni.html
employee #416
Aug10-04, 04:25 AM
Chronos, that site attempts to explain how the universe is expanding. In another section of the site, it explains how gravity is able to cause light to shift frequencies. This seems to tie into what Vern said.
One arguement is just as plausible as the other. One just takes a more logical approach.
Thanks for your input.
-employee #416
russ_watters
Aug10-04, 07:20 AM
Chronos, that site attempts to explain how the universe is expanding. In another section of the site, it explains how gravity is able to cause light to shift frequencies. This seems to tie into what Vern said.
One arguement is just as plausible as the other. Actually, one argument isn't more plausible than the other. You are mixing two completely separate issues. There would have to be an absolutely enormous amount of intergalactic mass to account for the observed redshift - iirc, the intergalactic medium would need to be more dense than the average galaxy. Unless you are suggesting there are lots of black holes out there...So, what visible characteristics of black holes make them differ from the visible characteristics of pulsars? I thought black holes were not visible, so how can they "look different" than pulsars. Chronos already addressed this, but don't you see that you answered your own question? If they aren't directly visible (ie, they don't give off their own radiation), then they certainly look different than objects that do give off their own radiation.What we see around black holes is what is happening through interactions at the event horizon. This is not the black hole itself. Right, black holes have event horizons (and an enormous amount of mass) and thats how we know they are black holes - so what's the problem? Or are you suggesting that an object with an event horizon (the distinguishing characteristic of a black hole) could be something else? A flat bill, webbed feet, and feathers - ehhh, still could be an elephant, right (just a type we've never seen before)? Don't you see how absurd that is?More massive objects do not mean they are visibly different. Black holes are very small. How are they visibly different just by being more massive? Au contraire - since all stars are virtually entirely hydrogen, mass is the primary determining factor in the properties of stars. For starters, massive ones are hotter.Black holes have not be observed directly. Only through indirect observations. So what? There are lots of things in nature that can't be seen directly, yet we know exist (ever hear of an elecron?) If an unseen object with enormous mass is sucking matter from a nearby star, it can't be anything else but a black hole - there is no other viable explanation. So to say they are visually different from pulsars is inaccurate. Maybe they look the same, but they are much more compact? You can't think of any observable physical characteristics that might be different? We've already discussed several...
according to Halton Arp red shift is the production of matter and that the older, the lesser the red shift,just a perspective!!
I haven't seen that paper of Halton Arp but I do remember some of his comments about problems with the Big Bang. If what Arp says in the quote above is true it may provide a way to test the red shift. Red shift due to doppler should have all frequencies shifted the same. Red shift due to Arp's assertion should be shifted less in the red frequencies than in the blue.
Does that sound right ?
Vern
How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest? (Do not assume we are the centre of the universe). The actual space between the two points is expanding. Twice as much space between two points = twice as much separation over time, appears as twice the speed to us.
Also, there's no reason to rule out the existance of black holes simply because YOU can't comprehend what it physically means. A black hole is simply matter sufficiently dense that its' escape velocity is greater than the speed of light and hence is not able to emit radiation. This does make it very difficult to observe directly, but does not mean it should be ruled out as an unreasonable proposition. It is logical to assume that such an object could exist provided an environment or process leading to the creation of such dense material exists in our universe. When we observe accretion discs in binary systems, the evidence suggests that the compact object involved may well be a small black hole in some cases. X-rays are a particularly effective method of exploring these systems as the compact object causes the matter in the accretion disc to reach enormous speeds and the resulting radiation emitted on impact is often in the X-ray band. The amount of energy being seen in some of these cases could only be explained by the presence of a black hole.
Other evidence for black holes includes (radio)active galaxies, do some reading.
There are several explanations for why we assume the universe to have finite age. If the universe is infinitely old, you would have to assume some radiation has been travelling for an infinite distance, why then do we see a limit on the the redshift values of radiation we detect. You could also read up on some explanations of Olber's Paradox; one conceivable explanation is that the age of the universe is finite. I know I've read some other better explanations to do with the Hubble constant and Euclidean n-space but the details escape me at the moment, I'm sure you could find some information on it through google.com if you were sufficiently interested.
How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest?
This suggests to me that the wave length of the light in increasing. We can assume that is due to the doppler effect, which you are doing. This assumption is by no means a certainty.
The bigbang theory was founded by a Catholic Priest who worked for Hubble as a mule driver. Hubble never really accepted the theory.
Keep on chuggin !!
Vern
I should go on to state that Abbe Georges Lemaitre went on to become a well known physicist in his own right. His "The Primeval Atom" was the orign of the big bang theory.
Vern
This is a very interesting thread.
Ive always said to myself that the origin of the universe would be the first question I would ask if I were to meet an intelligent extra terrestrial life form. To hear what they theorize.
Some other thoughts. If the universe has always existed wouldn’t the light emitted from every star/galaxy etc.. make our night sky full bright? If the universe is expanding, what is it expanding into? Is it creating space/time as its expanding? If you could travel past the point of the expansion what would that look like or what would that be?
If the theory that our universe is also going to collapse on itself is also true, could that point be traveled past if its no longer expanding? What happens to light if at its boundary if space is collapsing back on itself? If the expanding and collapsing of the universe is true, how many times has this process occurred? How many times will it last?
Its kinda like my perpetual motion idea. But as someone said before in my thread about needing to work hard for energy output e=mc ². So each time the universe has expanded and collapsed on itself it must be losing something as it surely cant last forever. So there must be an end point to this all. Understanding all the possible ends, if there is one may also help us understand the possible beginning, if there was one.
An infinite universe wouldn't necessarily result in brightness everywhere. We observe in space that the wavelength of light increases with distance. This we know is true even though we may never be absolutely certain of the cause. This increase would damp out the brightness, just as we see that it does.
Keep on chuggin !!
Vern
Entropy
Aug10-04, 02:11 PM
How do we know the universe is expanding? On average, a point twice the distance from us is moving away from us at twice the speed, what does this suggest?
I don't really believe in an expanding universe, or atleast one that is accelerating outward and will continue to do for eternity.
It is possible that the red-shift isn't cause only (or maybe even at all) by the Doopler effect. There are other ways red-shifts can occur, such as gravitational red-shift.
Personally I think any serious speculations on the what the universe was like in near the begining or will be like near the end is very bold. We know so little about what is happening in the cosmos that it would be stupid at this point in time to devote your life souly (or even a good portion of time) trying to proving a theory describing the begining and end of the universe. With our current knowledge, making a hardcore theory about the universe would be like determaining the ultimate fate of all mankind after studying one person's life for one minute.
With our current knowledge, making a hardcore theory about the universe would be like determaining the ultimate fate of all mankind after studying one person's life for one minute.
Thats great!
Locrian
Aug10-04, 02:49 PM
Gravitational red-shift as a source of the red shift was already examined in this thread. Do the math. It requires insane amounts of matter to cause the kind of red shift we observe. Suggesting that is the cause would mean we'd have to find vast amounts of matter.
Look for yourself. It simply isn't there.
What studies have you done to determine the amount of mass in the universe? What studies have you done on the redshift? Why, when matter is so clumped together, do the redshifts all reflect distances so smoothly? Do the math on how light will be shifted if traveling through a medium evenly dispersed with matter. Why doesen't it match what we observe? The idea that red-shifting is caused by gravity is a terrible, terrible, terrible predictor of observables. Why stick with it?
Do the math, do the experiments. You will see the idea is absurd.
Gravity is just one of the things that contribute to a red shift in aging light. There are many other things including that light might simply loose energy as it ages.
Humason's original data showed the universe's age was about 2 billion years. That didn't work for very long so they changed the Hubble constant to make it fit the 4 or 5 billion years needed to account for the age of the earth. Then that didn't work when better telescopes came along so they added an expansion period with arbitrary rules made up to fit the observations. It is about time now for another change to account for the 20 billion year old things we're beginning to observe.
They lost me when they changed Humason's original stuff.
Vern
Locrian
Aug10-04, 04:13 PM
They lost me when they changed Humason's original stuff.
Vern
That's a shame, since distance measuring methods were absolutely atrocious at the time. Hubble's own work shows error in the area of a factor of 10 - I know, I've done experiments to determine Hubbles Constant. Have you?
Astrophysics had hardly any tools going for it in 1929. It is no wonder things have changed.
Chronos
Aug10-04, 04:21 PM
That's science for you. The predicted size of the universe has been getting bigger and bigger since the ancient Egyptians [I think they were the ones] made the first official guess. As more and better data comes in, science changes. This is not the sole domain of cosmology, it is true in all fields of science. Now that the WMAP data has been crunched, the error factor in our calculations of when the universe became observable [transparent to light] has been greatly reduced. Furthermore, the fact that remote parts of the universe look greatly different than our neighborhood certainly implies some kind of evolutionary process has gone on over time, just like the fossil record on earth shows life many millions of years ago was much different than life today. You would think an ageless, eternal universe would look much the same everywhere at all times. It does not. Most of us therefore conclude it probably had an initial state and that initial state was vastly different than what has followed.
Footnote: If redshift is a highly unreliable distance indicator, it is hard to explain why entire classes of really exotic things we see in the universe [e.g., quasars] have huge redshifts.
Entropy
Aug10-04, 04:42 PM
Gravitational red-shift as a source of the red shift was already examined in this thread. Do the math. It requires insane amounts of matter to cause the kind of red shift we observe. Suggesting that is the cause would mean we'd have to find vast amounts of matter.
What the hell are you talking about? It hasn't been brought up in this thread until now. Show me the math/source that has calculated this result.
What studies have you done to determine the amount of mass in the universe? What studies have you done on the redshift?
Exactly, we don't know how much mass there is, so measuring the amount of gravitational red-shift is difficult. So we don't know if we can count out gravitational red-shift or not.
Why, when matter is so clumped together, do the redshifts all reflect distances so smoothly?
I'm pretty sure gravity doesn't reflect light.
employee #416
Aug10-04, 04:44 PM
Humason's original data showed the universe's age was about 2 billion years. That didn't work for very long so they changed the Hubble constant to make it fit the 4 or 5 billion years needed to account for the age of the earth. Then that didn't work when better telescopes came along so they added an expansion period with arbitrary rules made up to fit the observations. It is about time now for another change to account for the 20 billion year old things we're beginning to observe.
Never knew science had to "change" stuff to fit their observations. Magnificent, Vern!.
Chronos already addressed this, but don't you see that you answered your own question? If they aren't directly visible (ie, they don't give off their own radiation), then they certainly look different than objects that do give off their own radiation.
You're missing the whole point. They CANNOT look different. Their is no visual observations of black holes directly. Their is no visual comparison of a black hole to other objects. You can say interactions with a black hole an dother objects are different, but you can not say a black hole is visually different than any other object.
Lesuth, thanks for the reiteration.
Right, black holes have event horizons (and an enormous amount of mass) and thats how we know they are black holes - so what's the problem?
You took my complete thought, turned it into a fragment, and then asked a question about the fragment. That's the problem. A collapsed neutron star is a black hole. They have the same mass. A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape?
Your counter statement: A neutron star cannot be that massive, it's own gravity will cause it to condense into a black hole. Density is what differs a neutron star from a black hole, though they are the same exact objects.
Your platypus and elephant joke is getting old. Try a new one. It wasn't funny the first time.
Locrian
Aug10-04, 05:12 PM
I'm pretty sure gravity doesn't reflect light.
You misread my post. Reflect. As in show, or suggest. If we see an even and symmetric red shift that relates to distance, and you are proposing that mass is causing this then clearly matter must be spread out evenly. It isn't.
Exactly, we don't know how much mass there is...
When I asked you what studies you had done, I wasn't being rhetorical. We can judge about how much matter is out there because it exerts a force on things around it. I've taken data concerning this; what data have you taken? What experiments have you done? I was asking to see how much work you had done on the problem.
Light leaving a gravitational field has it's light reduced in frequency. However, if you are suggesting an even distribution of matter (which you must) then you need to take into account the fact that the light is falling towards matter between us and the emitter. This would raise it's frequency. Since you are suggesting a net decrease in frequency, then when you integrate over the distribution of matter between us and the object, the only way to create this red shift is to suggest a gradient of matter that would be easily detectable.
Unfortunately it isn't there. Galaxies far away do not contain significantly more matter than ones close... and they would have to. But then, do you even believe in galaxies, thinking as you do that matter is spread evenly throughout the universe? Don't think for a second dark matter will make up for the difference, because most dark matter is located around galaxies.
This is a terrible theory that is not based in any mathmatics and leads to contradictory conclusions at every turn.
Chronos
Aug10-04, 05:46 PM
Never knew science had to "change" stuff to fit their observations. Magnificent, Vern!.Happens all the time. Observation is how theory is validated. When observation contradicts theory, the theory must be modified or discarded. Note, however, that observation is not immune to fallability. Observational results must be confirmed before accepted as fact.... you can not say a black hole is visually different than any other object.Sure you can. A black hole does not emit any detectable radiation. A neutron star, like any other star, does....A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape?A neutron star must have a mass between about 1.4 and 2 solar masses. If less than that, it does not have enough gravity to overcome the electron degeneracy limit and can only collapse enough to form a white dwarf [a much different critter]. If more massive than that, but less massive than the neutron degeneracy limit [~2 solar masses], it cannot collapse enough to form a black hole, only down to a neutron star - which is not dense enough to prevent light from escaping.
But because of the low surface brightness of galaxies there were severe technical difficulties. Humason developed the technique and made most of the exposures and plate measurements. The velocities of 620 galaxies were measured, and the results, published 1956, still represent the majority of known values of radial velocities for normal galaxies.
Result of Google search.
According to these folks we're still using much of Humason's data.
Keep on chuggin !!
Vern
Entropy
Aug10-04, 08:24 PM
When I asked you what studies you had done, I wasn't being rhetorical. We can judge about how much matter is out there because it exerts a force on things around it. I've taken data concerning this; what data have you taken? What experiments have you done? I was asking to see how much work you had done on the problem.
Yeah, you already said that, show me some calculations, sources or something to back up you're claim. I just proposed a possiblity, you are looking to completely disprove a theory and you can't do that by just saying "you're wrong."
Light leaving a gravitational field has it's light reduced in frequency. However, if you are suggesting an even distribution of matter (which you must) then you need to take into account the fact that the light is falling towards matter between us and the emitter.
Don't forget that when light is emited from a star it has to work through a star's gravity well egro being red-shifted, and when we observe the light it is only blue-shifted by Earth's gravity, that is if you think the gravity of our and the other galaxies is negligible. Although it probably wouldn't be noticable for small or medium stars.
Unfortunately it isn't there. Galaxies far away do not contain significantly more matter than ones close... and they would have to. But then, do you even believe in galaxies, thinking as you do that matter is spread evenly throughout the universe? Don't think for a second dark matter will make up for the difference, because most dark matter is located around galaxies.
I don't think gravity would have to be evenly distributed, it just has to be near the source of the light.
Chronos
Aug11-04, 01:45 AM
Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.
Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.
True as usual; Chronos, but I'm thinking of the gravitational bending of the path as light propagates space. I don't think that would add to zero because the bend direction remains.
Vern
russ_watters
Aug11-04, 08:02 AM
Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.Damn, how did I miss that one? Good post.
Locrian
Aug11-04, 10:09 AM
Yeah, you already said that, show me some calculations, sources or something to back up you're claim. I just proposed a possiblity, you are looking to completely disprove a theory and you can't do that by just saying "you're wrong."
On the contrary, the burden of proof is on you. I'll humor you this time.
You are either suggesting that it is only the object playing the part, and therefore objects farther away are always heavier dependant upon the distance, or you are saying there is a matter gradient evenly distributed throughout the universe.
In the first case you'll be at a loss to explain the state of stars far away. There are visible galaxies very far away which, under your theory, should have huge amounts of extra mass. Yet they contain stars who are burning rather weakly. On top of that, their rotational inertia doesen't allow for the huge amount of mass you are trying to give them. If all stars in a galaxy are redshifted, then they must all be heavier. Significantly.
As you know the redshift due to gravity with an observer away from the source is
f' = f(1/(1 + P_e/c^2)) where P_e is the gravitational potential energy.
The gravitational potential energy involved will be the the integral of the gravitational field produced by the body from the point the light is emmitted to the point it is recieved.
\int GM/r^2 dr from R_1 to R_2. We'll take R_2 to be at infinity to give you the greatest benefit of the doubt. Once you integrate and take the limit your formula will be:
f' = f(1/(1 + GM/Rc^2))
Now let's take a star whose lyman alpha line has been shifted from a frequency of 25x10^12 to 8.3x10^12 (both in units of inverse seconds), which is far from the greatest shift to be seen, though it is sizable. Use a standard Sun type star that there are plenty of in the universe for your radius and you'll find that to create this red shift
M = 4x10^35, which is 100,000 times as heavy as our sun. :eek:
So in other words, to make this case that gravity is causing red shift, you are going to have to explain how everything half way to the edge of our vision is 100,000 times as heavy as everything near to us, and yet are visibly the same types of stars and do not show 100,000 times as much angular momentum.
Good luck :biggrin:
I won't bother with the matter gradient since you don't seem to feel matter is distributed evenly... and it's obviously just as invalid a hypothesis.
russ_watters
Aug11-04, 12:40 PM
You're missing the whole point. They CANNOT look different. Their is no visual observations of black holes directly. Their is no visual comparison of a black hole to other objects. You can say interactions with a black hole an dother objects are different, but you can not say a black hole is visually different than any other object. We're going around in circles, but it really is quite simple: if you have a light bulb suspended from the ceiling in an otherwise dark room, you can't see it if its turned off. But if you bump your head on it, you know its there, even though you can't see it. Now turn the light bulb on. Visually, what is the difference?
You make it sound like the failure to see that a black hole is actually a pulsar is a failure in our ability to observe it. It isn't: we don't observe emissions because there are none to observe. I think you may be confusing the absence of data with actual data showing no emissions. There is a difference. 0 is different from 10 - zero does not imply the absence of data or the possibility that if you could find some data it would be 10. A collapsed neutron star is a black hole. They have the same mass. A super-massive neutron star that has not collapsed yet can be classified as a black hole. It may have an escape velocity of that greater than light. It may have a nice hefty volume, but this neutron star is considered a black hole just because light can not escape? Maybe you could do some math to prove that an uncollapsed neutron star could have an event horizon. Hawking calculated that a neutron star of any mass does not have sufficient density to have an event horizon.
Now its sounding to me like you just don't understand what a black hole is.
Entropy
Aug11-04, 01:16 PM
On the contrary, the burden of proof is on you. I'll humor you this time.
I'm not trying to prove it, I just claimed it might be possible.
You are either suggesting that it is only the object playing the part, and therefore objects farther away are always heavier dependant upon the distance, or you are saying there is a matter gradient evenly distributed throughout the universe.
In the first case you'll be at a loss to explain the state of stars far away. There are visible galaxies very far away which, under your theory, should have huge amounts of extra mass. Yet they contain stars who are burning rather weakly. On top of that, their rotational inertia doesen't allow for the huge amount of mass you are trying to give them. If all stars in a galaxy are redshifted, then they must all be heavier. Significantly.
As you know the redshift due to gravity with an observer away from the source is
where P_e is the gravitational potential energy.
The gravitational potential energy involved will be the the integral of the gravitational field produced by the body from the point the light is emmitted to the point it is recieved.
dr from to . We'll take to be at infinity to give you the greatest benefit of the doubt. Once you integrate and take the limit your formula will be:
Now let's take a star whose lyman alpha line has been shifted from a frequency of 25x10^12 to 8.3x10^12 (both in units of inverse seconds), which is far from the greatest shift to be seen, though it is sizable. Use a standard Sun type star that there are plenty of in the universe for your radius and you'll find that to create this red shift
M = 4x10^35, which is 100,000 times as heavy as our sun.
So in other words, to make this case that gravity is causing red shift, you are going to have to explain how everything half way to the edge of our vision is 100,000 times as heavy as everything near to us, and yet are visibly the same types of stars and do not show 100,000 times as much angular momentum.
Good luck
I won't bother with the matter gradient since you don't seem to feel matter is distributed evenly... and it's obviously just as invalid a hypothesis.
I was thinking of similar equations to the ones you have there today at school. As a small first step I planned on calculating how much red-shift a photon would experience traveling from the sun's surface to Earth. Just to get an idea of how much light is effected by a "normal" star's gravity. Unfortunately, I didn't have my physics book with me today so I wasn't able to look up the radius of the sun or the sun's mass. But I did manage to form some rough equations that would describe the lose in momentum of a photon over a distance with a decreasing gravitational pull as it travels away.
I'm only use to calculating marcoscopic objects with mass so dealing with the gravitational effects on light is new to me. But from what I've deduced so far from my equations is that the evidence seems to be tilting in your favor. :tongue2:
But, I'm not going to rule out that gravity couldn't in some way be effecting the way we see light. Gravity can do some strange things sometimes and with so many sources and such a vast universe there are bound to be unseen variables.
Antonio Lao
Aug11-04, 01:45 PM
For our sake, the Big Bang is necessary. Although we can talk without any certainty about its real meaning and purpose which experts such as Hawking and Penrose remain silent and theories only reached up to the Planck time, it's a point of departure for all of us. A creationist view of reality.
On the other hand, if there was never a primeval explosion then the universe was always here and always will be here and there forever in a continuum of process without change and movement and indefinite uniformity. A steady state universe that is necessarily infinite in time and space with no change of any kind like the eternal true vacuum itself.
In actuality, the explosion can be just a change in energy density and not a change in enegy and mass by themselves for the density can change with mass and energy remain constant while the volume changes.
The change of energy density gives us pressure and this pressure is equal to 2/3 of the energy density for non-relativistic velocity and is equal to 1/3 of energy density for relativistic velocity.
Hi.
I'm sorry but I haven't manege to read the whole text yet so I might say somethings allredy told. I would just like to give a few thoughts set on the original question.
There has been qouit some talk about what was before the Big bang. But as much as I know (not much :smile: ) that is more a question of religion then of physics. So there is no need to talk about it.
But by the way I personaly don't belive in the Big bang theory. I find a therey of a nonconstent speed of light and a ever expending universe with an endles number of Big bang much easyer to belive alldo it is qouit new and not yet wiedly accepted.
employee #416
Aug12-04, 04:59 AM
Wow, forgot about my post. :redface:
Ok, Chronos, black holes do not have a distinct visible characteristic that makes it different from any other object. How hard is that to grasp? Visible characteristics of the black hole itself are unknown. We do not know how the object inside the black hole that causes the disturbance in space-time visually looks like. How can we note this unseen-visible characterstic to be different than a visual characteristic of another object? We can only distinguish the outer region of a black hole from an outer region of a similar object.
Take a room that has a width of 50m, a height of 10m and a depth of 50m. Place two light bulbs in the room at opposite ends of the width. One light bulb is a regular house-light bulb, while the other is a standard bulb you would find in an office building (those long ones). This room is made of clear glass. It is surrounded by a bigger room that is made of material that does not let light get through. You turn one of the lights on. Lets say the common house light. You allow an observer to observe this. You tell the observer he can go to any edge of the room as long as he does not pass half the width. You tell the observer that there is another light in the room that is off. You ask him to identify how do they visually differ. He responsds "One emitts light, the other doesnt." Is that really what you want? No, you know the observer is wrong. The other bulb can emitt light if it were turned on. He did not describe the visual characteristics. I.E. the shape of the bulbs. You know that one bult is rod shaped, while the other is a bulb shape.
russ_watters, I know what a black hole is. I understand the concept. You just miscomprehend what I'm asking.
For our sake, the Big Bang is necessary.
Well, not necessarily.
russ_watters
Aug12-04, 07:24 AM
russ_watters, I know what a black hole is. I understand the concept. You just miscomprehend what I'm asking. Sorry, but you don't. Your analogy shows this quite clearly: You ask him to identify how do they visually differ. He responsds "One emitts light, the other doesnt." Is that really what you want? No, you know the observer is wrong. The other bulb can emitt light if it were turned on. How do you know the other bulb can emit light? Maybe its burned out? Maybe its not connected to the switch? Indeed, in this case, the only thing the guy knows is that one emits light and one doesn't. This is exactly the issue with a black hole vs a star at the same mass. A black hole doesn't emit light and can't. You make the assumption that there is more information that could be collected that would show them to have the same characteristics. In the case of a black hole, there isn't (in the case of your light bulb, it might, but you have assumed it without evidence). Continuing: He did not describe the visual characteristics. I.E. the shape of the bulbs. You know that one bult is rod shaped, while the other is a bulb shape. One thing for sure - a black hole is smaller than a neutron star. Other than that, we don't know - it could be a singularity, or it might not be. But you are assuming structure that may not exist. You can't do that. At the moment, iirc, there are only 3 known basic properties of black holes: mass, spin, and charge (density is high but unknown). But that doesn't matter - we can still distinguish it from the neutron star.
So let me ask you this: if a black hole and neutron star of identical mass had identical structure (as you appear to be implying), why would one have an event horizon and one not?
I haven't seen that paper of Halton Arp but I do remember some of his comments about problems with the Big Bang. If what Arp says in the quote above is true it may provide a way to test the red shift. Red shift due to doppler should have all frequencies shifted the same. Red shift due to Arp's assertion should be shifted less in the red frequencies than in the blue.
Does that sound right ?
Vern
___________________________________________
no,its just there is a different reason for the shift and if you are interested in the book, with enormous amount of his evidence is "SEEING RED" can be purchased at (isbn #0-9683689-0-5) at infinite-energy.com or <http:// metaresearch.org>.perhaps even a book store,not sure, very good read, although very tech. if anything it gives a different perspective of the understanding of whats going on,which to me is important so we don't get stuck in certain way of thinking,which seems to be happening.but be critical of his book, that is also important.
I don't really believe in an expanding universe, or atleast one that is accelerating outward and will continue to do for eternity.
It is possible that the red-shift isn't cause only (or maybe even at all) by the Doopler effect. There are other ways red-shifts can occur, such as gravitational red-shift.
Personally I think any serious speculations on the what the universe was like in near the begining or will be like near the end is very bold. We know so little about what is happening in the cosmos that it would be stupid at this point in time to devote your life souly (or even a good portion of time) trying to proving a theory describing the begining and end of the universe. With our current knowledge, making a hardcore theory about the universe would be like determaining the ultimate fate of all mankind after studying one person's life for one minute.
___________________________________________
couldn't agree more,but that is exactly whats going on. thats why to me looking at other theories is important,there are many out there and it can be confusing but if you give yourself time,you'll sort it out at least to yourself,flexibility of mind is important but always criticize.
Chronos,
Gravitational redshift is only relevant to the emission source. Light passing through a gravity field would first be blue shifted [incoming], then red shifted [outgoing]. The net effect is zero.
Why do gravitational fields serve as magnifying lenses for distant light sources? What would be the lensing effect on the lightwaves?
One of the primary alternative theories for redshift was tired light, that it was simply encountering friction. As the light wasn't scattered, this idea was rejected. Frankly, I don't think it made much sense to begin with. Obviously proceeding waves would encounter more friction than succeeding ones, so the logical result would be blueshift.
What about energized light; That as amplitude decreases, frequency expands, much like a cracking whip. This would explain why light only travels so far before it fades out.
The first time I questioned the Big Bang theory was reading Stephen Hawking's A Brief History of Time and he made the point that for the universe to be as stable as it is, "Omega =1". In other words, the gravitational collapse of space must be in inverse proportion to the expansion of the universe. It struck me that a cyclical equilibrium between these two actions would be far more logical than the convenient coincidence of Big Bang Theory. Tests of the CMBR have since proven that this balance does exist and that ultimately space is flat.
Einstein proposed that the gravitational collapse of mass causes space to collapse. The fact is that this process releases tremendous amounts of radiation. Why doesn't this radiation result in the expansion of space? This is a point that I've heard raised by others.
An interesting article;
http://www.economist.com/science/displayStory.cfm?story_id=2404626
What if space does expand, but the universe doesn't? This would result in additional pressure on gravitational collapse. Exactly the effect currently assigned to dark matter.
It is a given that light passing through gravitational fields is magnified by a lensing effect and this is how we observe some of the most distant sources. What if this results in a blue shift? When you consider the distribution of galaxies across the universe, the further light travels, the more residual gravity fields it will cross. The resulting blueshift would reduce the overall redshift of distant sources, so the closer sources would have a greater average redshift. This creates the impression that the rate of expansion is increasing. Which would explain the effect assigned to dark energy.
Much is made of the CMBR as being predicted by BBT, but could there be other reasons for it. One of the problems it posed for BBT was that it was so smooth that information would have to travel at twice the speed of light for opposite sides of the universe to be similar.
Well, we have expanding energy/radiation and collapsing mass. Where is the connection? Could it be that empty space can only hold a minor amount of radiation in solution before it starts to condense out? Say this phase transition level is 2.7k(much like 32f is the freezing point of water) After this it starts to condense out as hydrogen.
What is the other side of the cycle? Gravitational vortexes of collapsing matter and radiating energy. Rather then black holes being some infinitely dense mass, or some hole into another dimension, what if they are essentially the eye of the storm, with most of the activity being what we see, much like a hurricane swirling around its center? Some energy does fall in, but this could be the source of the jets of protons shooting out the poles. So the matter is turned back into energy.
Of course, the experts say the universe and time and space, began in an instant, some 15 billion years ago, necessarily expanded faster then the speed of light to a size far greater than the visible universe and is ninety six percent invisible to everything but the math.
I suppose so, but I'm not going to hire any cosmologists as my accountants, just to be on the safe side.
Chronos
Aug13-04, 12:34 AM
Gravitational lensing bends light, it does not red, or blue, shift it. It works pretty much the same as an optical lense.
Chronos
Aug13-04, 01:03 AM
Wow, forgot about my post. :redface:
Ok, Chronos, black holes do not have a distinct visible characteristic that makes it different from any other object. How hard is that to grasp?They have characteristics that are not visible. That is the part that cannot be explained by any other explanation than they are black holes.Visible characteristics of the black hole itself are unknown.Agreed, a black hole has no visible characteristics. That is why we suspect they exist. We do not know how the object inside the black hole that causes the disturbance in space-time visually looks like.Agreed. How can we note this unseen-visible characterstic to be different than a visual characteristic of another object? We can only distinguish the outer region of a black hole from an outer region of a similar object.Any other object would have observable characteristics.Take a room that has a width of 50m, a height of 10m and a depth of 50m. Place two light bulbs in the room at opposite ends of the width. One light bulb is a regular house-light bulb, while the other is a standard bulb you would find in an office building (those long ones). This room is made of clear glass. It is surrounded by a bigger room that is made of material that does not let light get through. You turn one of the lights on. Lets say the common house light. You allow an observer to observe this. You tell the observer he can go to any edge of the room as long as he does not pass half the width. You tell the observer that there is another light in the room that is off. You ask him to identify how do they visually differ. He responsds "One emitts light, the other doesnt." Is that really what you want? No, you know the observer is wrong.The observer is correct.The other bulb can emitt light if it were turned on. He did not describe the visual characteristics. I.E. the shape of the bulbs. You know that one bult is rod shaped, while the other is a bulb shape.Irrelevant.russ_watters, I know what a black hole is. I understand the concept. You just miscomprehend what I'm asking.Russ is correct, you are incorrect. Do the math and you will see Russ is correct. Do not trust your intuition. Relativity does not obey it. Seriously, look at the math. Relativity is very hard conceptually. As Eddington said years ago.. 'Who is the third person who understands it?'
I haven't seen where the graviton, if it exists, is imune to gravity itselt. No other thing in the universe is imune to gratitational effects, how did the gravaton manage?
If the graviton is not imune to gravity, you could never have a complete black hole, just almost, almost, almost, like continously getting half way there.
Vern
C. Michael Turner
Aug13-04, 08:47 AM
Here is your answer. All matter is Bound gravitation. e=mc2 is really stating that free gravity, the wave, = Bound gravity, mass times the speed of the wave, light; squared.
All matter is a mass to energy transfer from a point of origin in wave form. This creates three actions. Time, space, and Gravitational wave sychronization. It also explains how time and space are relative and it explains why since the big bang matter is accelerating.F=ma If force is constant and mass is decreasing as it decays creating space then acceleration increases. Hope this helps! go to www.photontheory.com and click on papers- Dr. Turner's Universe for the long version.
C. Michael Turner
Aug13-04, 08:56 AM
Black hole evaporation and gravitons: Black holes are colasped matter decaying into gravitational waves which are like a monopole magnet. Some of the waves are so dense that they reform matter- see Stephen Hawking's latest press release and the rest is given off as microwave radiation and gravity waves( Monopolar gravitons) Mass is brought together be sychronization of waves throught the path of least resistance- therefore gravitons would never effect themselves except when they form matter under extreme heat and pressure.
Chronos,
Gravitational lensing bends light, it does not red, or blue, shift it. It works pretty much the same as an optical lense.
Yes, it bends it. That's why there are Eisteinian rings, etc., but it also magnifies it. That is why some of the most distant objects are able to be seen.
(I wish I kept the track of the article, it was about a year ago and it said that logically you are right, but in fact the effect I mention does happen, they just haven't explained it fully. I realize this needs backing, but I don't have enough time to keep track of what I need too...)
Chronos,
After googling this up one side and down the other, I have to give you this one...for the moment.
employee #416
Aug15-04, 02:18 PM
russ_watters, my point with that analogy was to point out that you are unable to visualize a black hole just as you are not able to visualize a light bulb that is not emitting light. You can not give characteristics of the light bulb that is not lit and the light bulb that is lit. You can not differentiate the two based on physical characterstics.
But you are assuming structure that may not exist.
I'm the only person who assumes things that do not exist?
So let me ask you this: if a black hole and neutron star of identical mass had identical structure (as you appear to be implying), why would one have an event horizon and one not?
It seems that yet again your miscomprehension has lead to false questioning. When I said identical structures, I meant that a black hole and neutron star could be very similar. The would BOTH have an event horizon. For they would BOTH allow light to fall in and not escape.
event horizon n. - The region, usually described as spherical, marking the outer boundary of a black hole, inside which the gravitational force is strong enough to prevent matter or radiation from escaping.
Please clarify what you mean by an event horizon. Going by that definition everything has an event horizon. An event horizon is dictated by mass OR EM not being *able* to escape.
Gravitational lensing bends light, it does not red, or blue, shift it. It works pretty much the same as an optical lense.
This bending of light causes shift. When light is bent at an angle, it accelerates towards a center. As you know through 1st year physics, when something turns, it has to accelerate towards a center. So, to keep light's velocity constant, it has to shift frequencies.
C. Michael Turner, I like your theory on how gravity works. It's consistent to what I think, but I describe it by different means. Oh well.
russ_watters
Aug15-04, 02:46 PM
russ_watters, my point with that analogy was to point out that you are unable to visualize a black hole just as you are not able to visualize a light bulb that is not emitting light. You can not give characteristics of the light bulb that is not lit and the light bulb that is lit. You can not differentiate the two based on physical characterstics. And clearly, you are wrong: there clearly is a difference between the two light bulbs: one is emitting light and one isn't. One has a higher temperature than the other. One is consuming more energy than the other. I won't assume that the one that isn't lit can't light, but similarly, you cannot assume that it can light. I'm the only person who assumes things that do not exist? Yep. You are assuming that a black hole has properties similar to a neutron star even though they are not observed and vice versa. You are attaching properties to both black holes and neutron stars that you want them to have, but that they do not, and cannot have. It seems that yet again your miscomprehension has lead to false questioning. When I said identical structures, I meant that a black hole and neutron star could be very similar. The would BOTH have an event horizon. For they would BOTH allow light to fall in and not escape. And again, I say, do the math and collect your Nobel prize: current theory says a neutron star is not dense enough to have an event horizon.Please clarify what you mean by an event horizon. Going by that definition everything has an event horizon. An event horizon is dictated by mass OR EM not being *able* to escape. An event horizon is the distance at which the escape velocity is greater than C. If every object were a point mass, then every object would have an event horizon. But you can't use that oversimplification here. Otherwise, you could dig down toward the core of earth and reach a place where the escape velocity is greater than C. But you can't: such a place does not exist. This bending of light causes shift. When light is bent at an angle, it accelerates towards a center. As you know through 1st year physics, when something turns, it has to accelerate towards a center. So, to keep light's velocity constant, it has to shift frequencies. No, in that case, it changes direction. Not frequency.
employee #416
Aug15-04, 03:01 PM
You are unably to visually declare a difference between the two light bulbs. You can not say "one is shaped different". You can not say "one has a greater volume than the other," nor can you say "one weighs more than the other."
Yep. You are assuming that a black hole has properties similar to a neutron star even though they are not observed. You are attaching properties to both black holes and neutron stars that you want them to have, but that they do not, and cannot have.
I'm not the only one. Science, as a whole, assumes things that have yet been proven to exist. My claims of neutron stars and black holes having the same properties is a CASE SCENARIO. For all you know, I could have said those two light bulbs were the exact same ones, but the observer does not know that.
. Otherwise, you could dig down toward the core of earth and reach a place where the escape velocity is greater than C. But you can't: such a place does not exist.
Density is what holds that claim as false. I'll agree with you on that one. If earth were much dense, then finding one point mass at the center could have an escape velocity greater than that of light.
No, in that case, it changes direction. Not frequency.
In order to change direction, you have to apply an acceleration. Your velocity increase. Light has to stay constant, so a shift in frequency must take place. I'm sure you are aware of how centripetal force works. It's just the bending of an objects curved path towards a center. A constant accelerated force is applied to keep that curved path bent.
russ_watters
Aug15-04, 04:27 PM
You can not say "one is shaped different". You can not say "one has a greater volume than the other," nor can you say "one weighs more than the other." Quite right: but you can say that one is hotter than the other. You can say one is brighter than the other. You are unably to visually declare a difference between the two light bulbs. Isn't brightness a property? Isn't temperature a property? I'm not the only one. Science, as a whole, assumes things that have yet been proven to exist. Sorry, that's not how the scientific method works. I guess you're claiming this about black holes, but black holes were predicted through mathematical derivation, then found through observation of the predicted properties. Assumption doesn't play a part here. My claims of neutron stars and black holes having the same properties is a CASE SCENARIO. ??? That doesn't alleviate the need for you to either prove it observationally or derive it mathematically. Density is what holds that claim as false. I'll agree with you on that one. If earth were much dense, then finding one point mass at the center could have an escape velocity greater than that of light. So extend that to neutron stars: are they dense enough at any mass to have an event horizon? In order to change direction, you have to apply an acceleration. Your velocity increase. That's not how velocity works. Velocity is a scalar speed and a vector direction. An acceleration can be either a change in direction or a change in speed. A satellite in orbit, for example, has constant scalar speed even with constant acceleration. If your assertion were correct, satellites would have constantly increasing (or decreasing) energy due to ther acceleration. They don't.
employee #416
Aug16-04, 07:50 PM
Quite right: but you can say that one is hotter than the other. You can say one is brighter than the other.
Not really. For all we know, a black hole can be one of the brightest objects in the universe, but we are not able to dictate that, because no light has been observed coming from a black hole. We can not say one is hotter than the other, but we can say the gases that are being accelerated can have a hot temperature which can account for the X-ray being emitted.
Isn't brightness a property? Isn't temperature a property?
Yes, they are, but we are unable to judge the two by those.
That's not how velocity works. Velocity is a scalar speed and a vector direction. An acceleration can be either a change in direction or a change in speed. A satellite in orbit, for example, has constant scalar speed even with constant acceleration. If your assertion were correct, satellites would have constantly increasing (or decreasing) energy due to ther acceleration. They don't.
When a satelite is in orbit, it is constantly being pulled towards a center of mass. This gives it direction change a and velocity change.
Chronos
Aug16-04, 11:37 PM
Originally Posted by russ_watters...Quite right: but you can say that one is hotter than the other. You can say one is brighter than the other.Not really. For all we know, a black hole can be one of the brightest objects in the universeNot really? The black hole radiates nothing. Matter swirling into a black hole is a separate issue.
Originally Posted by russ_watters
Isn't brightness a property? Isn't temperature a property?.Yes, they are, but we are unable to judge the two by those.
You appear to conveniently ignore observational evidence that refutes your flawed assumptions. Have you actually read past the part where we disagree with you? We give observational evidence and you give excuses.
Posted by russ_watters
That's not how velocity works. Velocity is a scalar speed and a vector direction. An acceleration can be either a change in direction or a change in speed. A satellite in orbit, for example, has constant scalar speed even with constant acceleration. If your assertion were correct, satellites would have constantly increasing (or decreasing) energy due to ther acceleration. They don't.When a satelite is in orbit, it is constantly being pulled towards a center of mass. This gives it direction change a and velocity change.This is a patently transparent attempt to ignore your original, erroneous assertion by pretending we misunderstood what you were trying to say.
Antonio Lao
Aug17-04, 06:46 AM
The black hole radiates nothing.
Aren't you forgetting Hawking radiation?
russ_watters
Aug17-04, 07:32 AM
Not really. For all we know, a black hole can be one of the brightest objects in the universe, but we are not able to dictate that, because no light has been observed coming from a black hole. We can not say one is hotter than the other, I was talking about the light bulb, but in any case, that is an incorrect understanding of how black holes (and light itself) work. Its a logical contradiction to say that something that emits no light can be "bright." ...but we can say the gases that are being accelerated can have a hot temperature which can account for the X-ray being emitted. That's how you calculate mass.Yes, they are, but we are unable to judge the two by those. What? Now you are saying we can measure properties that are different, but these properties aren't important? When a satelite is in orbit, it is constantly being pulled towards a center of mass. This gives it direction change a and velocity change. Yes it does. So complete it: does its velocity increase, decrease or stay the same?
employee #416, before I was seeing misunderstanding. Now I'm seeing what looks like intentional evasion. I think you see the problem you have with countering certain points and thats why you are ignoring some and evading others. And many of the ones you are answering - the things you are saying are just plain absourd. Think about them, please. Especially this question I asked before: ...are they [neutron stars] dense enough at any mass to have an event horizon? Don't throw away a chance to learn in favor of intellectual dishonesty because of pride. Aren't you forgetting Hawking radiation? No, I would say Chronos and I are simplifying. employee #416 is nowhere near ready for that and its different from the radiation we are talking about.
employee #416
Aug17-04, 06:40 PM
Not really? The black hole radiates nothing. Matter swirling into a black hole is a separate issue.
I think you missed the reasoning behind my response.
You appear to conveniently ignore observational evidence that refutes your flawed assumptions. Have you actually read past the part where we disagree with you? We give observational evidence and you give excuses.
Temperature and brightness are not observational evidences of the black hole itself. They are just measures of the outer region (event horizon). Observational evidence of the actually singularity (string if you are into the M-theory) has not been observed. So, don't give me this crap about observational evidence.
This is a patently transparent attempt to ignore your original, erroneous assertion by pretending we misunderstood what you were trying to say.
Eh? Not all orbits are complete circulars. Most are elliptical. When the object is orbiting and is going towards the farthest point it has to deccelerate and accelerate in a new direction. This involves velocity change.
I was talking about the light bulb, but in any case, that is an incorrect understanding of how black holes (and light itself) work. Its a logical contradiction to say that something that emits no light can be "bright."
Not really a contradiction as you say. We do not know what's going on past the event horizon as far as light. We have never observed inside of a black hole. Light enters the black hole, but does not escape. The light that is inside could very well give the black hole color, but we are unsure of that.
What? Now you are saying we can measure properties that are different, but these properties aren't important?
No, I'm saying that temperature and brightness are unknown for a black hole, ergo you are unable to use those two properties to differentiate from a black hole and another object.
...are they [neutron stars] dense enough at any mass to have an event horizon?
Ok, I'm not sure if I've said this, but here it is again: Neutron stars and black holes are the SAME thing. One is just more dense than the other. To answer you question: Yes, they are dense enough at any mass to have an event horizon. Neutron stars and black holes have the same mass upon collapsing. Black hole is just another way of saying "a neutron star that is dense enough to not allow light to escape."
employee #416
Aug17-04, 06:42 PM
Aren't you forgetting Hawking radiation?
Hawkings radiation is not what I'm explaining. Black holes do not emit anything. The Hawking's radiation is just the particle/anti-particle pairing at the event horizon, where one of the two will fall in, while the other doesn't. That is not the black hole emitting anything.
russ_watters
Aug17-04, 11:29 PM
Observational evidence of the actually singularity (string if you are into the M-theory) has not been observed. So, don't give me this crap about observational evidence. Indeed, scientists aren't convinced there even is a singularity. But that doesn't change the fact that there is an event horizon and by definition, a black hole. Anyway, if you can prove that the singularity doesn't exist, please do - and then go pick up your Nobel prize: Hawking will be jealous.
Eh? Not all orbits are complete circulars. Most are elliptical. When the object is orbiting and is going towards the farthest point it has to deccelerate and accelerate in a new direction. This involves velocity change. That's also a transparent evasion: in a circular orbit, there is a constant acceleration - as you said before. Now you're changing the argument because you have no answer to my question from the last post: is the velocity of an object in a circular orbit increasing or decreasing? Not really a contradiction as you say. We do not know what's going on past the event horizon as far as light. We have never observed inside of a black hole. Light enters the black hole, but does not escape. The light that is inside could very well give the black hole color, but we are unsure of that. This implies that what goes on inside a black hole could be relatively "normal," and that the event horizon is some sort of opaque barrier: its a clear indication you don't understand how a black hole works: namely, what gravitational redshift does in/just outside of a black hole.No, I'm saying that temperature and brightness are unknown for a black hole, ergo you are unable to use those two properties to differentiate from a black hole and another object. Another misunderstanding of what black holes are: brightness has a value: ZERO. Temperature quite simply doesn't exist.
Ok, I'm not sure if I've said this, but here it is again: Neutron stars and black holes are the SAME thing. One is just more dense than the other. They are the same except where they are different? Thats a contradiction: If they were the same, they'd be the same [density]. That's like saying a red giant and white dwarf are the same thing, just different density. Red and blue are the same color, just different. Rough is the same as smooth, just rougher. Apparently you don't understand what a neutron star is either - though your assertion is so absurd I have a hard time accepting you don't see it. In any case, you can't just assert it. Like I've said now a good half dozen times you must prove it.
To answer you question: Yes, they are dense enough at any mass to have an event horizon. Neutron stars and black holes have the same mass upon collapsing. Black hole is just another way of saying "a neutron star that is dense enough to not allow light to escape." That's another contradiction: if a neutron star collapses into a black hole its not a neutron star anymore. Neutron stars have specific densities based on the force that holds the nucleus of an atom together. What I am asking is can a neutron star - a star with that specific structure - ever acquire enough mass to get an event horizon while still retaining its structure? If you believe it can, prove it.
Also, I shouldn't need to say this again, but a black hole is, by definition, "An area of space-time with a gravitational field so intense that its escape velocity is equal to or exceeds the speed of light." (dictionary.com) Even if it had some unknown internal structure of any kind, it would still, by definition, be a black hole. That said, one internal structure it could not have is the structure of a neutron star: neutron stars are not dense enough to have event horizons.
employee #416
Aug18-04, 04:56 AM
Indeed, scientists aren't convinced there even is a singularity. But that doesn't change the fact that there is an event horizon and by definition, a black hole. Anyway, if you can prove that the singularity doesn't exist, please do - and then go pick up your Nobel prize: Hawking will be jealous.
I was not saying that singularities do not exists. You are good at twisting stuff around. I was simply using that to tell you that observational evidences don't mean anything.
That's also a transparent evasion: in a circular orbit, there is a constant acceleration - as you said before. Now you're changing the argument because you have no answer to my question from the last post: is the velocity of an object in a circular orbit increasing or decreasing?
To tell you the truth, I'm quite unsure of how to answer that. I'm thinking the velocity itself is constant, which would make acceleration 0. Most orbits are eccentric though, giving them the property of varying acceleration.
This implies that what goes on inside a black hole could be relatively "normal," and that the event horizon is some sort of opaque barrier: its a clear indication you don't understand how a black hole works: namely, what gravitational redshift does in/just outside of a black hole.
Gravitational redshift outside of a black hole? Gravitational shift inside a black hole? How can those be observed? I know what gravitational redshift is. With the gravity as intense as it is around a black hole, redshift can not be observed.
Another misunderstanding of what black holes are: brightness has a value: ZERO. Temperature quite simply doesn't exist.
Give me a source that states inside a black hole, there is no brightness. I'll be happy. So, now, you are saying temperature isn't a property of a black hole? Earlier you were saying it was, well, you were asking me if it was.
They are the same except where they are different? Thats a contradiction: If they were the same, they'd be the same [density]. That's like saying a red giant and white dwarf are the same thing, just different density. Red and blue are the same color, just different. Rough is the same as smooth, just rougher.
Well, what do you know. I actually agree with you on everything that was stated in that quote. Everything that seems to be different is actually the same. We just need different names to account for some differences between the two. You can make a red giant a white dwarf; you can make red look like blue; you can make rough smooth. You can make a black hole a neutron star and vice versa.
What I am asking is can a neutron star - a star with that specific structure - ever acquire enough mass to get an event horizon while still retaining its structure?
May I ask you a question to verify something, before answering?
I know that you think my knowledge on black holes is fairly limited. I assure I have read sites that are very good at describing black holes. I'm talking #1 search on google. Not only that, but I've read books on black holes, so please, do not think I'm limited in knowledge. I'm just thinking outside of the box.
russ_watters
Aug18-04, 12:19 PM
I'm amazed (and a little disappointed) this thread survived the purge. But I'm finished with it anyway.
employee #416, you stated in another thread you disagree with the definition of a black hole. Your arbitrary discomfort does not constitute a scientific argument and not accepting a definition means you won't ever accept the concept that the definition is describing. Therefore, discussion is utterly pointless.
Add to this your continued evasion of the orbit/velocity issue and I feel you are not debating honestly or making an honest effort to learn.
This board exists to help teach people (including the moderators) science. Take a step back and consider why you are here.
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