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Tags astronomy , astrophysics , black holes , cosmology , general relativity , physics

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Old 25th March 2018, 11:42 PM   #121
Pixie of key
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Originally Posted by fuelair View Post
You can show anything expanding with 3d animation. So what, it doesn't mean it is reality it is simply something to do with a half-way decent computer and 3-d program for it. You do know, I hope, that because you can model something in a computer program does not in any way show that it happens in real life/reality don't you????????
Thats true, but when somebody making 3 D animation which show how eternal pushing force recycling itself in infinity 3 D space, we can discuss whether this could really be true.

This is important for both. So why can you argue why that can not be? To me because I get those arguments from you.

But when you can not show 3D space animation how space will expand, then I can not even try to criticize its way of expanding.
and you do not even have to try to defend its way of expanding.
It is enough for you to say, later that space is more hokkus pokkus. The same thing when you say, God created world glory. How? So that the universe was born. Is this science?

.
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Old 26th March 2018, 12:07 AM   #122
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Galaxy centre supermassive cincentrations are not big neutronstar.

This supermassive concentrations expanding and emit expanding dark matter which have a nature of expanding protons and expanding neutrons.

Supermassive objects consist of such massive and dense sedimentation as their radiation consists of the nuclei of the dark matter atoms. And they can produce a detectable substance if the external energy / pusher force causes zillions of them to expand at the same time as explosive way. Then new expanding star centre is very big pressure with out pulling force etc.

.
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Old 26th March 2018, 04:10 AM   #123
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Mate, just because you don't know the maths, doesn't mean it's hocus pocus. The universe is under no obligation to simplify itself some more if you slept harder in school. Your being too... mentally unequipped by half to understand some basic maths concepts, doesn't mean the universe has to be at the level of whatever special-school colouring books you're comfortable with.

And again, the idea that something is real because you can make a 3D animation, is two steps beyond stonking stupid. You just need to look at Skyrim and the like for why such a notion is stupid. People have animated dragons, fireballs, flying tentacled monsters, lightsabers, plasma weaponry, and other such impossible stuff. Especially as someone who does some 3D modelling, hell, I animated some of that myself. I CAN animate a lightsaber for example, and did just that a couple of times, but that doesn't make it real. The very notion that being able to animate something is in any form of shape evidence of it being true, is already no longer in the domain of not knowing the language, and straight into the domain of underpants-on-head pencils-up-the-nose stonking stupidity.

Edit: not to mention that even as animating skills go, being proud of showing something grow, is on par with being proud that you can fart. You only need to start Blender and use the scroll wheel to see a cube growing or shrinking. That kind of thing is about as impressive as animation skills go, as shoving pencils up your nose is to writing skills. If you think THAT is what should impress people into believing your silliness... yeah, you might be disappointed.
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Last edited by HansMustermann; 26th March 2018 at 04:22 AM.
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Old 26th March 2018, 04:46 AM   #124
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Originally Posted by HansMustermann View Post
Mate, just because you don't know the maths, doesn't mean it's hocus pocus. The universe is under no obligation to simplify itself some more if you slept harder in school. Your being too... mentally unequipped by half to understand some basic maths concepts, doesn't mean the universe has to be at the level of whatever special-school colouring books you're comfortable with.

And again, the idea that something is real because you can make a 3D animation, is two steps beyond stonking stupid. You just need to look at Skyrim and the like for why such a notion is stupid. People have animated dragons, fireballs, flying tentacled monsters, lightsabers, plasma weaponry, and other such impossible stuff. Especially as someone who does some 3D modelling, hell, I animated some of that myself. I CAN animate a lightsaber for example, and did just that a couple of times, but that doesn't make it real. The very notion that being able to animate something is in any form of shape evidence of it being true, is already no longer in the domain of not knowing the language, and straight into the domain of underpants-on-head pencils-up-the-nose stonking stupidity.

Edit: not to mention that even as animating skills go, being proud of showing something grow, is on par with being proud that you can fart. You only need to start Blender and use the scroll wheel to see a cube growing or shrinking. That kind of thing is about as impressive as animation skills go, as shoving pencils up your nose is to writing skills. If you think THAT is what should impress people into believing your silliness... yeah, you might be disappointed.
who says that the universe must be so complex that its way of acting can not be represented by 3D animation?

I think that universe mode of operation is so simple that it can display 3 D animation. I can be wrong, but I suppose I'm right.

when somebody making 3 D animation which show how eternal pushing force recycling itself in infinity 3 D space, we can discuss whether this could really be true.

This is important for both. So why can you argue why that can not be? To me because I get those arguments from you.

But when you can not show 3D space animation how space will expand, then I can not even try to criticize its way of expanding.
and you do not even have to try to defend its way of expanding.
It is enough for you to say, later that space is more hokkus pokkus. The same thing when you say, God created world glory. How? So that the universe was born. Is this science?

.
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Last edited by Pixie of key; 26th March 2018 at 04:47 AM.
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Old 26th March 2018, 05:29 AM   #125
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Originally Posted by HansMustermann View Post
The very notion that being able to animate something is in any form of shape evidence of it being true, is already no longer in the domain of not knowing the language, and straight into the domain of underpants-on-head pencils-up-the-nose stonking stupidity.
Originally Posted by Pixie of key View Post
I think that universe mode of operation is so simple that it can display 3 D animation. I can be wrong, but I suppose I'm right.
Well, that settles it.


Originally Posted by Pixie of key View Post
Is this science?
What you are doing is not science.

As for what you are doing, HansMustermann described it well.
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Old 26th March 2018, 05:34 AM   #126
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Originally Posted by W.D.Clinger View Post
Well, that settles it.



What you are doing is not science.

As for what you are doing, HansMustermann described it well.
You say well, but i say that he dont get a point what i try to say.

Anyway, expanding space is not even naked empire.

It is god which you cant explain.

.
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Old 26th March 2018, 05:39 AM   #127
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WHO SAYS that the universe must be so complex that its way of acting can not be represented by 3D animation?

Maybe god tell you that?

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Old 26th March 2018, 05:49 AM   #128
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Sure, the people who tell you to study the mathematics of what's actually going on are the blind believers, and the person who claims something is real because he can imagine it and draw a cute little picture is the scientist...
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Old 26th March 2018, 07:36 AM   #129
HansMustermann
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Originally Posted by Pixie of key View Post
WHO SAYS that the universe must be so complex that its way of acting can not be represented by 3D animation?
Who said that that's relevant in any form or shape? Your entitlement delusions?
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Old 26th March 2018, 11:34 AM   #130
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Originally Posted by Reality Check View Post
...
The science that there is no real singularity in Schwarzschild's solution at the event horizon. That is a coordinate singularity that can be removed by choosing a different frame.
...
Hm you probably meant "The science says that there is no real singularity in Schwarzschild's solution at the event horizon."

Wikipedia says, in its article on "Redshift" (https://en.wikipedia.org/wiki/Redshift ):
Quote:
1 + z = femitted/fobserved
= (1 - 2GM/r)-1/2
(in units for which c=1, see middle of the page; I hope you understand the mathematical notation I have used, x-1/2 = 1/[x1/2]).

Now, what do you think happens when the radius r becomes equal to the Schwarzschild radius (https://en.wikipedia.org/wiki/Schwarzschild_radius ) rs=2GM ?
Answer: 1+z is singular at that point, and "blows up" as r → rs.
This is confirmed by the "Redshift" wiki page, which states:
Quote:
... as an object approaches the event horizon the red shift becomes infinite. ...
So, general relativity is a singular theory for what really matters, namely the observable redshift, and is ruled out by the broad (and not very clear) basic principle which says that no fundamental physical theory should have singularities.

Now, many extremely compact objects have been discovered in the universe (neutron stars and black hole candidates). Has any astronomer discovered an object with a large gravitational redshift z, of the order of say, z=2 ? (such values are common for cosmological redshifts). No, I don't think so, the largest gravitational redshift ever observed for a star seems to be z = 89/300000 = 3.0 x 10-4 only (https://en.wikipedia.org/wiki/Gravit...te_dwarf_stars , http://www.einstein-online.info/spot...html#section-2 ), for Sirius B, a white dwarf.

Another of the problems with general relativity is that its energy density is not positive-definite (unlike the energy density of the electromagnetic field
u=(E2+B2)/2). This usually leads to bad divergences in numerical simulations (fields becoming infinite).
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Old 26th March 2018, 11:59 AM   #131
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Originally Posted by Michel H View Post
So, general relativity is a singular theory for what really matters, namely the observable redshift
You have not made any case for why this is the thing that "really matters".

Quote:
and is ruled out by the broad (and not very clear) basic principle which says that no fundamental physical theory should have singularities.
Yeah, no. That "principle" does not constitute any form of proof. Furthermore, there's a rather glaring problem with your application of it. Namely, why is femitted/fobserved what we should be looking at? Why not look instead at fobserved/femitted? That quantity doesn't explode, it just goes to zero, and there's no problem with quantities going to zero.

And it's not like this is unique either. If you look at the thermodynamics of paramagnets, you'll find that temperature diverges to infinity for the unmagnetized state in a magnetic field. Energy doesn't diverge, only temperature. But inverse temperature has no singularity. Thermodynamics is a very, VERY well established fundamental theory. The singularity in one quantity isn't a problem. Or do you think it is? Do you have a problem with standard thermodynamics as well?

Quote:
Now, many extremely compact objects have been discovered in the universe (neutron stars and black hole candidates). Has any astronomer discovered an object with a large gravitational redshift z, of the order of say, z=2 ? (such values are common for cosmological redshifts). No, I don't think so, the largest gravitational redshift ever observed for a star seems to be z = 89/300000 = 3.0 x 10-4 only (https://en.wikipedia.org/wiki/Gravit...te_dwarf_stars , http://www.einstein-online.info/spot...html#section-2 ), for Sirius B, a white dwarf.
You seem to be confused about the nature of astronomical observations. Light coming from a black hole will not come from near the surface of the black hole. It will come mostly from the accretion disk, the inner edge of which is actually far outside the event horizon, because that's where almost all the matter available to radiate will be. That matter will be traveling at close to the speed of light in orbit around the black hole. It will be red-shifted due to relativistic velocity effects, and further doppler shifted either blue or red if the orbit is approaching or receding from us. The distances involved mean that we almost certainly won't be able to get the necessary angular resolution to distinguish the approaching from the receding side, blurring it all together. You won't be able to extract a gravitational redshift out of all those even larger effects.

Which means that, as a practical matter, the measurement you want cannot be done. So the fact that we haven't done it isn't in any way a strike against the theory. We shouldn't expect to be able to do it.
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Old 26th March 2018, 12:07 PM   #132
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Originally Posted by Pixie of key View Post
Thats true, but when somebody making 3 D animation which show how eternal pushing force recycling itself in infinity 3 D space, we can discuss whether this could really be true.

This is important for both. So why can you argue why that can not be? To me because I get those arguments from you.

But when you can not show 3D space animation how space will expand, then I can not even try to criticize its way of expanding.
and you do not even have to try to defend its way of expanding.
It is enough for you to say, later that space is more hokkus pokkus. The same thing when you say, God created world glory. How? So that the universe was born. Is this science?

.
You clearly are unaware of my posts even here, I do not have the remotest belief in a god or any creator. No evidence in the slightest of one. The best thinkers have come up with a model that is supported by all the science and the appropriate math that we currently have on the topics. Those only do I trust.

However, if further data proves the current version wrong scientifically then I shall adapt to that theory. That is how we do and follow science.
Religion just helps those who control/made it up gain power they should never be allowed to have or use.
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Old 26th March 2018, 12:15 PM   #133
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Originally Posted by Pixie of key View Post
Galaxy centre supermassive cincentrations are not big neutronstar.

This supermassive concentrations expanding and emit expanding dark matter which have a nature of expanding protons and expanding neutrons.

Supermassive objects consist of such massive and dense sedimentation as their radiation consists of the nuclei of the dark matter atoms. And they can produce a detectable substance if the external energy / pusher force causes zillions of them to expand at the same time as explosive way. Then new expanding star centre is very big pressure with out pulling force etc.

.
Wherefrom are you pulling what you are claiming re dark matter (as well as dark energy). At this point we have no functional idea of what it is - only possible indications of it's existence. Nevermind what I was writing in this sentence, it is much more rational to just say we have no idea what or how dark energy and dark matter work just that their existence is probable. the external force thing is functionally meaningless as you have described it!!!
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Old 26th March 2018, 12:17 PM   #134
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Originally Posted by HansMustermann View Post
Mate, just because you don't know the maths, doesn't mean it's hocus pocus. The universe is under no obligation to simplify itself some more if you slept harder in school. Your being too... mentally unequipped by half to understand some basic maths concepts, doesn't mean the universe has to be at the level of whatever special-school colouring books you're comfortable with.

And again, the idea that something is real because you can make a 3D animation, is two steps beyond stonking stupid. You just need to look at Skyrim and the like for why such a notion is stupid. People have animated dragons, fireballs, flying tentacled monsters, lightsabers, plasma weaponry, and other such impossible stuff. Especially as someone who does some 3D modelling, hell, I animated some of that myself. I CAN animate a lightsaber for example, and did just that a couple of times, but that doesn't make it real. The very notion that being able to animate something is in any form of shape evidence of it being true, is already no longer in the domain of not knowing the language, and straight into the domain of underpants-on-head pencils-up-the-nose stonking stupidity.

Edit: not to mention that even as animating skills go, being proud of showing something grow, is on par with being proud that you can fart. You only need to start Blender and use the scroll wheel to see a cube growing or shrinking. That kind of thing is about as impressive as animation skills go, as shoving pencils up your nose is to writing skills. If you think THAT is what should impress people into believing your silliness... yeah, you might be disappointed.
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Old 26th March 2018, 12:24 PM   #135
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Originally Posted by Pixie of key View Post
who says that the universe must be so complex that its way of acting can not be represented by 3D animation?

I think that universe mode of operation is so simple that it can display 3 D animation. I can be wrong, but I suppose I'm right.

when somebody making 3 D animation which show how eternal pushing force recycling itself in infinity 3 D space, we can discuss whether this could really be true.

This is important for both. So why can you argue why that can not be? To me because I get those arguments from you.

But when you can not show 3D space animation how space will expand, then I can not even try to criticize its way of expanding.
and you do not even have to try to defend its way of expanding.
It is enough for you to say, later that space is more hokkus pokkus. The same thing when you say, God created world glory. How? So that the universe was born. Is this science?

.
Yes, you can imagine you are correct. Unfortunately our group here has a number of persons who know you are wrong. To start with do you actually believe the expansion will have no anomalies of any kind in it. Because you have to find a way around that to even model the move from the earlier space to the current space. and many of the anomalies do not leave any signs by this time of what may have happened in the Very Long Past. And without those you just can't predict future changes.
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Old 26th March 2018, 12:29 PM   #136
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Originally Posted by Pixie of key View Post
You say well, but i say that he dont get a point what i try to say.

Anyway, expanding space is not even naked empire.

It is god which you cant explain.

.
Prove god (you cannot and never will).
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Old 26th March 2018, 12:34 PM   #137
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Originally Posted by Pixie of key View Post
WHO SAYS that the universe must be so complex that its way of acting can not be represented by 3D animation?

Maybe god tell you that?

.
No offense, but you really should not try bringing a fictional character into your arguments. It really does not help you. At all!

Claiming god means you are trying to prove that science is all wrong because magic guy with no brain is working randomly just for the hell of it!!!
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Old 26th March 2018, 12:40 PM   #138
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Originally Posted by Ziggurat View Post
You have not made any case for why this is the thing that "really matters".



Yeah, no. That "principle" does not constitute any form of proof. Furthermore, there's a rather glaring problem with your application of it. Namely, why is femitted/fobserved what we should be looking at? Why not look instead at fobserved/femitted? That quantity doesn't explode, it just goes to zero, and there's no problem with quantities going to zero.

And it's not like this is unique either. If you look at the thermodynamics of paramagnets, you'll find that temperature diverges to infinity for the unmagnetized state in a magnetic field. Energy doesn't diverge, only temperature. But inverse temperature has no singularity. Thermodynamics is a very, VERY well established fundamental theory. The singularity in one quantity isn't a problem. Or do you think it is? Do you have a problem with standard thermodynamics as well?



You seem to be confused about the nature of astronomical observations. Light coming from a black hole will not come from near the surface of the black hole. It will come mostly from the accretion disk, the inner edge of which is actually far outside the event horizon, because that's where almost all the matter available to radiate will be. That matter will be traveling at close to the speed of light in orbit around the black hole. It will be red-shifted due to relativistic velocity effects, and further doppler shifted either blue or red if the orbit is approaching or receding from us. The distances involved mean that we almost certainly won't be able to get the necessary angular resolution to distinguish the approaching from the receding side, blurring it all together. You won't be able to extract a gravitational redshift out of all those even larger effects.

Which means that, as a practical matter, the measurement you want cannot be done. So the fact that we haven't done it isn't in any way a strike against the theory. We shouldn't expect to be able to do it.
This sounds like dubious excuses to me. You have a theory (GR) which makes this extraordinary claim that clocks "freeze" on the event horizon (infinite gravitational time dilation), and that the observable redshift becomes infinite. Extraordinary claims require extraordinary evidence, but where is the evidence? There is zero evidence (for strong fields). If we can theoretically have redshifts z=20 for example, perhaps z≃1.5 only would be observable for some reason (accretion disk or other). But even that cannot be seen apparently. I don't think general relativity should be exempt from the requirement that extraordinary claims require extraordinary evidence. Remember also that this is a theory which assumes the equivalence of all reference frames (whether accelerated or inertial), even though we know that accelerated charges (or masses) radiate, and not those moving with constant velocities.

Last edited by Michel H; 26th March 2018 at 12:57 PM.
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Old 26th March 2018, 12:50 PM   #139
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Originally Posted by Michel H View Post
This sounds like dubious excuses to me. You have a theory (GR) which makes this extraordinary claim that clocks "freeze" on the event horizon (infinite gravitational time dilation),
No, it emphatically does NOT say that. Once again, clocks do not stay at the event horizon. They cannot. Light coming from clocks is not the clock itself.

Quote:
Extraordinary claims require extraordinary evidence, but where is the evidence? There is zero evidence (for strong fields).
Again, this is wrong. Gravitational wave observations is very strong evidence for strong fields.

Quote:
I don't think GR relativity should be exempt from the requirement that extraordinary claims require extraordinary evidence.
It's not. But you are wrong about both what the claims are and what the evidence is.

Quote:
Remember also that this is a theory which assumes the equivalence of all reference frames (whether accelerated or inertial), even though we know that accelerated charges (or masses) radiate, and not those moving with constant velocities.
You have fundamentally misunderstood what GR is saying. You can have multiple reference frames for the same physical event. And you can describe that physical event in any of those reference frames. This is the sense in which reference frames are "equivalent". But you aren't actually comparing the same event in different reference frames. You're actually comparing different physical events.
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Old 26th March 2018, 01:27 PM   #140
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Originally Posted by fuelair View Post
Yes, you can imagine you are correct. Unfortunately our group here has a number of persons who know you are wrong. To start with do you actually believe the expansion will have no anomalies of any kind in it. Because you have to find a way around that to even model the move from the earlier space to the current space. and many of the anomalies do not leave any signs by this time of what may have happened in the Very Long Past. And without those you just can't predict future changes.
You forget that there is old light which is expanding cosmologys way because all expanding lights interactive with each other.

And quess what?

You can not manipulate yours magic curving space or expanding space!!!

I can try manipulate light moving direction with old expanding light.

Long wall in space, lets put other end telescope. Just look faraway galaxy which place we know and i predict it is look to be different place where we know it really are.

So, my model is something what we can explain with words and visually way!!!

AND ALSO WE CAN PROOF MY IDEA WITH SCIENCE EXPERIEMENT!!!

YOU HAVE NOTHING AT ALL!!!

Yours expanding space is not science!!!

It is just like god is.

You can only believe there is god which name is expanding space!!!

.
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Old 26th March 2018, 01:51 PM   #141
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@Michael H
1. There are some attempts to come up with something that doesn't have a coordinate singularity. E.g., I mentioned gravastar a few times already. Might want to google it, if you're looking for a non-crazy alternative to black holes. Mind you, AFAIK there's no evidence for them yet, but at least the maths is sane.


2. Neutron stars, however aren't even a contender. Now I feel bad that I threw away the post where I was doing the maths, so let's do it again for the black hole that was linked to a bit above.

A solar mass black hole has a radius of about 3km. (I'll round everything brutally.) This thing is 3 million solar masses, and since luckily for me the Schwarzschild radius is simply proportional to mass. It would have a radius of about 10 million km, or 1010m. That means a volume of about 4*1030 cubic metres. By way of comparison the sun's volume is about 1.4*1027 cubic metres.

So it's about 3,000 times or so bigger in volume, and 3,000,000 times heavier, which is awesome for doing maths on the back of the napkin. My sacrifices to the maths gods have paid off

So it's about 1000 times denser than the sun, which puts its weight somewhere around 1.4 million kg per cubic metre.

Which sounds like a lot, but here's the thing: a neutron star's density starts a bit over around 3*10[sup]17[sup] kg/m3. (Well, ok, closer to 4 but let's be generous.) Our thing is over 200 BILLION times less dense than that.

If there's a hard surface at or outside the event horizon, what is holding it from collapsing into something smaller than the event horizon? Never mind that it's over a million times the mass that neutron degeneracy could hold up anyway, but neutron degeneracy hasn't even started to happen at that density. We're 200 billion times less dense than where we'd have neutronium there to hold that surface.

So what's holding it?


3. In fact, what we have there as a density, about 1.4*106 kg/m3 is only around the point where you start getting electron degeneracy.

However, if electron degeneracy were able to support that kind of mass, then none of the neutron stars we've observed would have been possible. Because if electron degeneracy could support some 3,000,000 solar masses worth of star remnant, there's no way that 2 solar masses would collapse into a neutron star.

That's an ad absurdum right there, so we can rule out the electron degeneracy there.


4. The size of a black hole whose Hawking radiation (after red shift) is the wavelength of the cosmic background radiation is the size of the moon. For reference, that corresponds to a black body spectrum temperature of about 2.7 Kelvin.

Now.. the black body temperature of Hawking radiation is inversely proportional to the mass. So when by the time we even get an actual black hole of, say, about 3 solar masses or so, the black body temperature you're seeing for those redshifted photons is measured in NANO-Kelvins or so.

So, while Ziggurat was correct in pointing out you can't separate that from the accretion disk emissions, it's even more perverse than that. How do you separate a signal that weak even from the cosmic microwave background? Once you also look at what Messrs Stefan–Boltzmann say about energy vs temperature, namely that it's proportional to the FOURTH power, a nearly 3K emission will absolutely DROWN any nano-Kelvin range signal. The galactic background noise alone is literally billions of billions of billions of billions times stronger than the emissions from a very small black hole.

So WHAT emission data do you have, to support the idea that the red shift doesn't match?
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Old 26th March 2018, 01:53 PM   #142
HansMustermann
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@Pixie of key
Light doesn't interact with light, other than by a very slight (*TA-DA*) warping the space-time. If you don't have space curvature in that model, then old light doesn't do anything at all to any old, new, slightly used, or recently renovated light.

Short version: when you come up to that kind of ideas, go to sleep. You're drunk
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Old 26th March 2018, 02:22 PM   #143
Michel H
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Originally Posted by HansMustermann View Post
@Michael H
1. There are some attempts to come up with something that doesn't have a coordinate singularity. E.g., I mentioned gravastar a few times already. Might want to google it, if you're looking for a non-crazy alternative to black holes. Mind you, AFAIK there's no evidence for them yet, but at least the maths is sane.


2. Neutron stars, however aren't even a contender. Now I feel bad that I threw away the post where I was doing the maths, so let's do it again for the black hole that was linked to a bit above.

A solar mass black hole has a radius of about 3km. (I'll round everything brutally.) This thing is 3 million solar masses, and since luckily for me the Schwarzschild radius is simply proportional to mass. It would have a radius of about 10 million km, or 1010m. That means a volume of about 4*1030 cubic metres. By way of comparison the sun's volume is about 1.4*1027 cubic metres.

So it's about 3,000 times or so bigger in volume, and 3,000,000 times heavier, which is awesome for doing maths on the back of the napkin. My sacrifices to the maths gods have paid off

So it's about 1000 times denser than the sun, which puts its weight somewhere around 1.4 million kg per cubic metre.

Which sounds like a lot, but here's the thing: a neutron star's density starts a bit over around 3*10[sup]17[sup] kg/m3. (Well, ok, closer to 4 but let's be generous.) Our thing is over 200 BILLION times less dense than that.

If there's a hard surface at or outside the event horizon, what is holding it from collapsing into something smaller than the event horizon? Never mind that it's over a million times the mass that neutron degeneracy could hold up anyway, but neutron degeneracy hasn't even started to happen at that density. We're 200 billion times less dense than where we'd have neutronium there to hold that surface.

So what's holding it?


3. In fact, what we have there as a density, about 1.4*106 kg/m3 is only around the point where you start getting electron degeneracy.

However, if electron degeneracy were able to support that kind of mass, then none of the neutron stars we've observed would have been possible. Because if electron degeneracy could support some 3,000,000 solar masses worth of star remnant, there's no way that 2 solar masses would collapse into a neutron star.

That's an ad absurdum right there, so we can rule out the electron degeneracy there.


4. The size of a black hole whose Hawking radiation (after red shift) is the wavelength of the cosmic background radiation is the size of the moon. For reference, that corresponds to a black body spectrum temperature of about 2.7 Kelvin.

Now.. the black body temperature of Hawking radiation is inversely proportional to the mass. So when by the time we even get an actual black hole of, say, about 3 solar masses or so, the black body temperature you're seeing for those redshifted photons is measured in NANO-Kelvins or so.

So, while Ziggurat was correct in pointing out you can't separate that from the accretion disk emissions, it's even more perverse than that. How do you separate a signal that weak even from the cosmic microwave background? Once you also look at what Messrs Stefan–Boltzmann say about energy vs temperature, namely that it's proportional to the FOURTH power, a nearly 3K emission will absolutely DROWN any nano-Kelvin range signal. The galactic background noise alone is literally billions of billions of billions of billions times stronger than the emissions from a very small black hole.

So WHAT emission data do you have, to support the idea that the red shift doesn't match?
I was not thinking about Hawking radiation (quantum field theory would also need major changes by the way, in my opinion). I noted that general relativity predicts extreme redshifts and extreme slowing down of clocks near the event horizon and, after a century of GR, such phenomena have never been observed. Einstein wrote in 1939:
Quote:
The essential result of this investigation is a clear understanding as to why the "Schwarzschild singularities" do not exist in physical reality. ...
This investigation arose out of discussions the author conducted with Professor H. P. Robertson and with Drs. V. Bargmann and P. Bergmann on the mathematical and physical significance of the Schwarzschild singularity. The problem quite naturally leads to the question, answered by this paper in the negative, as to whether physical models are capable of exhibiting such a singularity
http://www.cscamm.umd.edu/people/fac...warzschild.pdf
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Old 26th March 2018, 02:25 PM   #144
Olof
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Originally Posted by Pixie of key View Post
You forget that there is old light which is expanding cosmologys way because all expanding lights interactive with each other.

And quess what?

You can not manipulate yours magic curving space or expanding space!!!

I can try manipulate light moving direction with old expanding light.

Long wall in space, lets put other end telescope. Just look faraway galaxy which place we know and i predict it is look to be different place where we know it really are.

So, my model is something what we can explain with words and visually way!!!

AND ALSO WE CAN PROOF MY IDEA WITH SCIENCE EXPERIEMENT!!!

YOU HAVE NOTHING AT ALL!!!

Yours expanding space is not science!!!

It is just like god is.

You can only believe there is god which name is expanding space!!!

.
Pixie of key is really a crackpot. He has disturbed the Finnish science forums almost for 20 years. I think he has mental health problems.
The best way is to ignore his senseless messages. Let him talk to himself!

He preaches his senseless jargon and makes somersaults and cartwheels on marketplace in his home town and distributes the "One Simple Principle" leaflets to people.

He has also been "barked" almost all Finnish scientists, "because they don't understand his excellent Insights".
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Old 26th March 2018, 03:02 PM   #145
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Originally Posted by Michel H View Post
I was not thinking about Hawking radiation (quantum field theory would also need major changes by the way, in my opinion). I noted that general relativity predicts extreme redshifts and extreme slowing down of clocks near the event horizon and, after a century of GR, such phenomena have never been observed.
Since we would not expect to be ABLE to observe that, why is that an impediment? We observe other things which ARE consistent with the predictions of black holes, and which no competing theory can explain.

Quote:
Einstein wrote in 1939:
General Relativity is hard. It's so hard, in fact, that even its inventor failed to fully understand its implications. But the fact that he invented it doesn't mean that nobody can go any further with it than he did. And we have. A lot of progress has been made since 1939. This quote doesn't prove black holes are wrong, it proves that Einstein was fallible. The objections he raised have long since been answered.
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Old 26th March 2018, 03:34 PM   #146
HansMustermann
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Originally Posted by Michel H View Post
I was not thinking about Hawking radiation (quantum field theory would also need major changes by the way, in my opinion). I noted that general relativity predicts extreme redshifts and extreme slowing down of clocks near the event horizon and, after a century of GR, such phenomena have never been observed.
Actually, I'm mentioning the Hawking radiation BECAUSE it is an example of exactly that extreme red-shift. The centre of that black body spectrum should actually correspond to a very high temperature, BUT by the time it got reasonably out of the extremely curved space, it had been redshifted into the nano-kelvins range.

In fact what I'm saying is just exactly how truly extreme that red-shift is.

But I'm also illustrating the problem with trying to either verify or disprove that kind of truly extreme red shift. ANY signal ends up drowned even by the CMB, much less the signal from the accretion disk.

So how would you even go about either proving or disproving it?
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Old 26th March 2018, 03:37 PM   #147
HansMustermann
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Originally Posted by Olof View Post
Pixie of key is really a crackpot. He has disturbed the Finnish science forums almost for 20 years. I think he has mental health problems.
The best way is to ignore his senseless messages. Let him talk to himself!

He preaches his senseless jargon and makes somersaults and cartwheels on marketplace in his home town and distributes the "One Simple Principle" leaflets to people.

He has also been "barked" almost all Finnish scientists, "because they don't understand his excellent Insights".
Well, I'm starting to get that idea. I assumed that I could just give him some basic information, if I phrased it just simple enough and stuff. But I guess I was just wrong.
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Old 26th March 2018, 04:29 PM   #148
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Originally Posted by Pixie of key View Post
You forget that there is old light which is expanding cosmologys way because all expanding lights interactive with each other.

And quess what?

You can not manipulate yours magic curving space or expanding space!!!

I can try manipulate light moving direction with old expanding light.

Long wall in space, lets put other end telescope. Just look faraway galaxy which place we know and i predict it is look to be different place where we know it really are.

So, my model is something what we can explain with words and visually way!!!

AND ALSO WE CAN PROOF MY IDEA WITH SCIENCE EXPERIEMENT!!!

YOU HAVE NOTHING AT ALL!!!

Yours expanding space is not science!!!

It is just like god is.

You can only believe there is god which name is expanding space!!!

.
You are aware, I trust, that you are still not making understandable English sentences just because you are stringing English words together. Seriously, like most languages there is an accepted structure for English sentences, just as there is an accepted structure for whatever language you are used to speaking.

You will have no chance of making points here or having attention made/paid (except where your science is way off/very misleading) if you do not get some experience/assistance from someone familiar with proper English sentences. You are neither the first or the last I will likely have to mention that point to.
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Old 26th March 2018, 04:37 PM   #149
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http://old.post-gazette.com/healthsc...oles0616p4.asp

gravistar ^^^^^^^^^^^^^^^^^^^


https://en.wikipedia.org/wiki/Gravastar


gravastar^^^^^^^^
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Old 26th March 2018, 05:26 PM   #150
W.D.Clinger
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Originally Posted by Michel H View Post
Now, what do you think happens when the radius r becomes equal to the Schwarzschild radius (https://en.wikipedia.org/wiki/Schwarzschild_radius ) rs=2GM ?
The r coordinate of Schwarzschild coordinates is analogous to the latitude coordinate of a Mercator projection. If you consult an atlas of the world, you will find that Mercator projections centered on the equator never show the north or south pole. That's because the Mercator projection has a coordinate singularity at those poles.

The fact that "south" is not well-defined at the north pole is another example of a coordinate singularity. Those coordinate singularities do not imply dragons or an edge of the earth or anything at all spectacular. What they do imply is that you need to switch to another page of your atlas in order to visualize the territory surrounding the north pole.

The well-known Schwarzschild coordinate singularity at the so-called Schwarzschild radius is no more of a real singularity than the ambiguity of the word "south" at the north pole. It means you need to switch to a different chart in your atlas if you want to visualize what's going on at the event horizon.

I'm not kidding about "chart" and "atlas". Those words are part of the standard definition of a differentiable manifold. Some authors prefer to say "map" or "coordinate patch" instead of "chart", but almost all mathematicians speak of an atlas of charts/maps/patches.

Differentiable manifolds are what differential geometry is about, and differential geometry is the mathematical prerequisite for having an informed opinion about the technical aspects of general relativity.

There are no shortcuts. Sorry.

Originally Posted by Michel H View Post
So, general relativity is a singular theory for what really matters, namely the observable redshift, and is ruled out by the broad (and not very clear) basic principle which says that no fundamental physical theory should have singularities.
Although you mistake coordinate singularities for real singularities, general relativity does imply real singularities such as a big bang or the singularity at the center (not the event horizon) of a black hole. Almost all mathematicians and physicists agree that those singularities signify a breakdown of the theory. Most physicists believe a successful reconciliation between general relativity and quantum mechanics will eventually eliminate those singularities.

For the moment, however, those real singularities do indicate something is definitely wrong with general relativity at the farthest extremes of physics.

You, however, are mistaking coordinate singularities for real singularities.

Originally Posted by Michel H View Post
This sounds like dubious excuses to me. You have a theory (GR) which makes this extraordinary claim that clocks "freeze" on the event horizon (infinite gravitational time dilation),
General relativity does not make that claim. You are the person who is making that claim.

General relativity says an observer "at infinity" who prefers to use a chart in which he/she/it is at rest will see clocks slow down as they approach the event horizon of a black hole and never advance past the time at which those clocks actually pass through the event horizon. That is one consequence of the coordinate singularity discussed above. General relativity also says there are infinitely many equally valid charts that don't have that coordinate singularity. In the equally valid charts that are likely to be preferred by an observer moving with clocks that are free-falling into a black hole, the clocks don't slow down at all.

If that's confusing you, then you don't understand why the theory of relativity is called the theory of relativity.

Originally Posted by Michel H View Post
There is zero evidence (for strong fields).
Untrue. Evidence for strong fields has been cited throughout this thread, including the recent observations of gravitational waves as predicted by general relativity for the collision of black holes.

Originally Posted by Michel H View Post
Remember also that this is a theory which assumes the equivalence of all reference frames (whether accelerated or inertial), even though we know that accelerated charges (or masses) radiate, and not those moving with constant velocities.
The problem you're having is that you do not understand the mathematics of relativity. (There's no shame in that. Few people do. The mathematics is accessible only to highly motivated individuals who have been studying the prerequisite mathematics for years.)

All coordinate systems agree on which charges are accelerated and which are moving along geodesics. Your "reference frames" and "constant velocities" terminology comes from special relativity. In general relativity, you use the geodesic equation to distinguish accelerated from geodesic world lines.

Originally Posted by Michel H View Post
I noted that general relativity predicts extreme redshifts and extreme slowing down of clocks near the event horizon and, after a century of GR, such phenomena have never been observed.
As is often noted here, both the time dilation of special relativity and the apparent (because relativistic) slowing of clocks predicted by general relativity have been observed and are compensated for by a GPS system used by millions of people every day.

As for black holes, we have observed gravitational waves whose form was calculated using the same equations that predict black holes and redshifts and slowing of clocks. It would be hard to imagine a more spectacular confirmation of those predictions than we have observed (although I suppose one could make a case for the Hubble expansion, cosmic microwave background, and gravitational lensing).

Originally Posted by Michel H View Post
In the early years of general relativity, Einstein and many other physicists had a hard time distinguishing coordinate singularities from real singularities, primarily because they were accustomed to doing all of their calculations within a single chart (aka map or coordinate patch). Although Einstein was aware that his choice of chart was arbitrary, he and most other physicists of the time often forgot (or perhaps never realized) that most of the interesting spacetime manifolds cannot be covered by a single chart. They were therefore inclined to make the mistake of regarding the limitations and singularities of their preferred chart as a physical limitation or singularity.

We now recognize that as a mistake. Einstein and other pioneers can be excused. Science and mathematics take time and effort, even when developed by geniuses.

Nowadays, however, mistaking coordinate singularities for real singularities is recognized as a common rookie mistake, and rightly so.

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Old 26th March 2018, 06:00 PM   #151
Ziggurat
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Originally Posted by W.D.Clinger View Post
We now recognize that as a mistake. Einstein and other pioneers can be excused. Science and mathematics take time and effort, even when developed by geniuses.

Nowadays, however, mistaking coordinate singularities for real singularities is recognized as a common rookie mistake, and rightly so.
Note also that Einstein was, of necessity, a rookie at General Relativity. He had no one to teach him. It's remarkable that he didn't make even more mistakes than he did, given the complexity of the subject.
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Old 26th March 2018, 06:53 PM   #152
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@Michael H
I would also add (and someone please correct me if I'm wrong) is that when you throw QM into it, any distance smaller than a Planck length is unobservable and meaningless in physics.

Why is that important?

Because from the frame of reference of a distant observer in which he/she/it is at rest -- i.e., where you get the stopping clocks problem -- you're never going to observe anything happening closer than 1 Planck length from the black hole. When whatever is falling in gets asymptotically closer (again, in your frame of reference) to the event horizon than 1 Planck length, nothing more changes beyond that.

You never get to see it divide by zero even in your frame of reference. You don't get to actually see the clock stop.

Basically the red-shift of the Hawking radiation is as much red-shift as you can possibly observe from a black hole. Anything more than that, you fundamentally can't observe in your frame of reference, by any imaginable experiment.

So basically I wouldn't get too hung up upon the fact that something hasn't been observed, that nobody is ABLE to observe.

In fact, if someone managed to observe that, now THAT would mean that either QM or GR are broken.
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Old 26th March 2018, 06:55 PM   #153
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Originally Posted by fuelair View Post
Yeah, it's gravAstar. But when you get a magazine journalist, and not from a physics journal at that, to write about it, well, actually I'd say it's nowhere near as big a mistake as I would have expected. Usually they make a more complete hash of that kind of topics
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Old 26th March 2018, 07:06 PM   #154
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@W.D.Clinger and Ziggurat
Well, that brings me back to my old question, though. (Hey, I AM a rookie, so I'm allowed to make rookie mistakes :P)

Basically: from the point of view (ok, chart) of someone on S1, which orbits around Sagittarius A*, are they orbiting an actual black hole, or a bunch of matter which never finished falling beyond the event horizon? Seems to me like it should be the latter, since in that chart, all the mass of the black hole is just outside the event horizon, innit?

Which brings me to: when we observe events like the the giant black hole sucking a red dwarf dry, like mentioned in this thread, or the merger of black holes, or other such events, is there actually a way for that to confirm that there is an event horizon there? Because it seems to me like from OUR chart, we're just seeing the matter get stuck on the outside of the event horizon.

I keep hearing that it shows there is no hard surface, but essentially in our chart it can't look like anything else than a surface anyway.


Standard disclaimer: some people expect me to lead into some crackpot theory when I ask about GR, but I'm still too lazy to come up with a good one. I might get to it one day, but for now I'm really just asking if I understood the real thing right. Since if I judge myself what I understood, see Dunning-Kruger.
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Old 26th March 2018, 07:50 PM   #155
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Originally Posted by HansMustermann View Post
I keep hearing that it shows there is no hard surface, but essentially in our chart it can't look like anything else than a surface anyway.
It doesn't behave like a surface, though. The only light coming from an object falling into a black hole is whatever light the object naturally gives off, but extremely red-shifted. If that object hit a surface just outside the putative event horizon, the impact energy would be tremendous. If would create an incredible amount of light, a brilliant flash which, even accounting for the red shift, would be monumentally brighter than the light given off by something that falls through an event horizon.

In order to be indistinguishable from an event horizon, the surface would have to be such that all impacts were soft, and all the energy from the impact was absorbed internally. But the existence of some hypothetical form of matter behaving that way is a far more extraordinary claim than black holes existing.
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Old 26th March 2018, 08:30 PM   #156
W.D.Clinger
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Originally Posted by HansMustermann View Post
Basically: from the point of view (ok, chart) of someone on S1, which orbits around Sagittarius A*, are they orbiting an actual black hole, or a bunch of matter which never finished falling beyond the event horizon? Seems to me like it should be the latter, since in that chart, all the mass of the black hole is just outside the event horizon, innit?
Before answering, let me address several assumptions that appear to be implicit within your questions.

The first implicit assumption is that there's some kind of one-to-one correspondence between observers and charts (or points of view). No, any observer can use any chart or charts that deal with the portion of spacetime that's of interest. (The idea that an observer's situation determines a chart comes from special relativity, where Einstein's original expositions tended to assume each observer uses an orthonormal inertial frame of reference in which the observer is at rest. Even then, however, there were infinitely many inertial frames of reference for each observer, because you still get to choose which direction to call x and which to call y, at which point I guess the z and t directions are determined.)

It sounds as though you are also assuming the orbiting observer's chart would use Schwarzschild coordinates. An observer at rest with respect to Schwarzschild coordinates must be at an infinite distance from the black hole. In practice, observers sufficiently far from the black hole are sufficiently at rest with respect to the coordinates for the "observer at rest with respect to the coordinates" idea to be an excellent approximation.

If an observer is orbiting the black hole, however, then the observer must be too close to be "at rest" with respect to Schwarzschild coordinates. In fact, an observer in orbit is in "free fall". If you (or that observer) want to use a chart in which the observer's spatial coordinates don't change, then you can do so, but that chart will not use Schwarzschild coordinates.

The observer will have infinitely many charts from which to choose. The observer might prefer coordinate systems in which the observer is at rest with respect to the coordinates, while the black hole rotates. That might not be too confusing provided there is nothing else in the universe, but an observer using that kind of chart might suffer a migraine if there are stars and galaxies and galactic clusters rotating around the black hole as well. The observer might therefore prefer a coordinate system in which the observer's spatial coordinates are changing as you might expect for an object in orbit around a planet or star or black hole; for an observer in orbit around a black hole at a sufficiently safe distance, that coordinate chart won't be greatly different (in the vicinity of the observer) from the coordinates we use when considering the orbit of the moon around earth or the earth around the sun.

In particular, the orbit will be the same regardless of whether the black hole's mass lies at the center of the black hole, or is distributed throughout some kind of shell surrounding the black hole, or is distributed throughout some normal star that has the same total mass as the black hole, or is indeed a normal star that hasn't yet collapsed into a black hole. In that sense, it doesn't matter whether the mass of the black hole lies inside or outside the event horizon.

An observer who understands general relativity will realize that clocks falling into the black hole don't actually slow down or stop as they approach the event horizon, even though they will appear to do so because light and other signals from those clocks won't be able to reach the observer once the clocks have passed through the event horizon.

An observer who mistakes the Schwarzschild coordinate singularity for a real singularity might think the clocks actually slow down as they approach the event horizon and come to a complete stop as they reach it.

It turns out that all correct calculations describe the same physics regardless of whether the observer understands general relativity or mistakes the Schwarzschild coordinate singularity for a real singularity, so long as both observers are only considering physics outside the event horizon. The observer who understands general relativity will be able to calculate what happens to objects that pass through the event horizon, however, while an observer who doesn't understand general relativity is likely to become confused and think something truly weird is happening at the event horizon.

Originally Posted by HansMustermann View Post
Which brings me to: when we observe events like the the giant black hole sucking a red dwarf dry, like mentioned in this thread, or the merger of black holes, or other such events, is there actually a way for that to confirm that there is an event horizon there? Because it seems to me like from OUR chart, we're just seeing the matter get stuck on the outside of the event horizon.
We might notice the complete absence of signals emanating from within the event horizon. In other words, we might notice that the event horizon and its interior is completely black.

On the other hand, we might also notice the extreme red shift of signals coming from objects that approach the event horizon. If we understand general relativity, we can compare the observed red shift (and related phenomena) to what is predicted by general relativity, and then we might conclude that what's going on at and inside the event horizon is probably consistent with general relativity as well.

If we don't understand general relativity, we'll probably just remain confused. We can remove our confusion by diminishing our orbital speed so we fall out of orbit and into the black hole, which will give us an opportunity to observe first-hand what happens at and inside the black hole. According to general relativity, nothing special happens except---well, let's just hope we wrote our last letters home before we crossed the event horizon, because any email we send from inside the event horizon is going to remain inside the event horizon forever.

So we can observe what happens first hand, but we won't ever be able to publish our findings in a journal based on earth (or anywhere else that lies outside the black hole's event horizon).

Last edited by W.D.Clinger; 26th March 2018 at 08:33 PM. Reason: added last two words (in gray)
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Old 26th March 2018, 09:40 PM   #157
HansMustermann
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Well, I'm _assuming_ this: that we're getting the data from something like a radio-telescope on or around Earth observing the events. And that any photons reaching such such a device _necessarily_ are red-shifted and all according to a point of reference where said device not only is at rest, but is basically the origin of its coordinate system.

I'm also assuming that if we're collecting the data from 27,000 light years from Sagittarius A*, yeah, the difference between that and actually being at infinite distance is lost in the decimals. Whatever further red shift happens between here and infinity, is not going to be very significant. So I'm ignoring it, which I think is the standard modus operandi in physics.

I'm also assuming that the fact that we are accelerating around it -- albeit not quite in free fall just from its mass, because it's not the only mass within that 27,000 ly radius sphere -- is not going to distort the data very significantly. The acceleration is rather small compared to the kind of data we're measuring. I assume.

I do understand that you can do the maths and everything according to a clock falling into the black hole and all, but until such time as we can actually drop a clock into it, we're not going to get any data collected from that clock's frame of reference.

Basically it seems to me like while the above assumptions are not 100% correct, they are fairly reasonable as approximations go. Please correct me if I'm wrong.

I am also familiar with Birkhoff's theorem, so yes, I'm aware that the orbit would be the same. I wasn't proposing to distinguish the existence of an event horizon by orbit.

But generally, well, that's the kind of reason why I put that disclaimer there. Everyone seems to assume that I have some deeper idea there, when, really, I don't. I guess I don't know how to ask right, or something. I definitely wasn't questioning whether the GR maths still works when you approach an event horizon, for example. I was just asking whether we can actually measure anything that would actually confirm that anything passed through the event horizon.

And the "measure" part is the only reason I'm hung up on a chart centered on me, so to speak. Because while I can do the maths for an instrument falling into the black hole, I can't actually drop one into it. I'll have to do with one that's sitting somewhere around here, and the photons that it measures in its own frame of reference.
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Old 26th March 2018, 09:50 PM   #158
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Originally Posted by HansMustermann View Post
@Pixie of key
Light doesn't interact with light, other than by a very slight (*TA-DA*) warping the space-time. If you don't have space curvature in that model, then old light doesn't do anything at all to any old, new, slightly used, or recently renovated light.

Short version: when you come up to that kind of ideas, go to sleep. You're drunk
When i say, light expanding and get other lights expanding faster, it is science.

It is science because we can make science experiement with light.

We can try check out if light expanding and get other lights expanding faster.

When you say that space expanding, it is not science. It is religion.

You cant manipulate space. You cant make science experiemet for space.

You can only believe.

.
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Old 26th March 2018, 09:51 PM   #159
HansMustermann
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That said...

Originally Posted by W.D.Clinger View Post
We might notice the complete absence of signals emanating from within the event horizon. In other words, we might notice that the event horizon and its interior is completely black.
Wouldn't such signals have to be incredibly strong to be measurable even theoretically, though? I mean, the way I understand it, the Hawking radiation itself is a quite strong signal where it starts, but ends up red-shifted to a point where even the CMB drowns it. And if any signal came from inside (and I'm not saying it can), could we even detect it?
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Old 26th March 2018, 09:57 PM   #160
HansMustermann
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Originally Posted by Pixie of key View Post
When i say, light expanding and get other lights expanding faster, it is science.

It is science because we can make science experiement with light.
Precisely, my lad. We can actually do experiments with light, and we can see that light does NOT push other light away, nor get any other light to expand faster.

And see, THAT is science: actually measuring stuff.

What you're doing is the polar opposite of science. You're just MAKING UP uninformed stuff about what you think light does. You're just pulling delusional bullcrap out of your own imagination. That's NOT science.

So basically before presuming to lecture anyone about what science is, do have the basic human decency of learning WTH you're talking about. Because it's not just stupid, but rather presumptuous too, to lecture anyone about what science is when so far you've amply proven that you don't know Jack Squat about what the scientific method even is, much less how it works.

Make actual predictions -- that is MATHEMATICAL ones -- and test them against reality. THAT is science. The moment you even start with the standard crackpot idiocy that oh, you just know how things work, someone else can do the maths, you just told everyone right there that you do NOT do science. You don't even know what science is, my dear delusional person.


Edit: basically Star Wars isn't a documentary. Just because there lightsabers push each others away, doesn't mean that actual light does that. That's the PROBLEM with the mentally challenged idea that seeing a funky CGI animation is somehow proof of how reality works.
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