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Author: heiwosheiwos Date: May 2, 2008 04:30
I've come across a blog post that attempts to show that general
relativity (GR) contradicts itself about black holes. No, I didn't
write it so please don't lambaste me. I just want to know what's wrong
with it. I hope this isn't yet another group where not even an
imagined problem with mainstream physics can be discussed. I hope the
charter isn't a cruel trick.
There's been some discussion about the blog (note I didn't start it)
in another forum. You can find both the blog (called "On Cosmology")
and the discussion thread (at scienceforums) by googling for "No Black
Holes (General Relativity Contradicts Itself)" (put within double
quotes). I'd put the links here but Google Groups doesn't allow that
for some reason.
The best problem about the blog they've come up with in the thread is
that it lacks math. I don't see that as a major problem. The way I see
it, the blog post is a paradox, just like the twin paradox or Bell's
spaceship paradox, both of which are described in words, without math.
I'm confident there's a simple solution, also describable in words,
that shows a problem with the blog. The blog uses only a few widely
published predictions of GR.
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Author: Oh NoOh No Date: May 2, 2008 06:44
Thus spake heiwos gmail.com>>I've come across a blog post that attempts to show that general
>relativity (GR) contradicts itself about black holes. No, I didn't
>write it so please don't lambaste me. I just want to know what's wrong
>with it. I hope this isn't yet another group where not even an
>imagined problem with mainstream physics can be discussed. I hope the
>charter isn't a cruel trick.
>
>There's been some discussion about the blog (note I didn't start it)
>in another forum. You can find both the blog (called "On Cosmology")
>and the discussion thread (at scienceforums) by googling for "No Black
>Holes (General Relativity Contradicts Itself)" (put within double
>quotes). I'd put the links here but Google Groups doesn't allow that
>for some reason.
>
>The best problem about the blog they've come up with in the thread is
>that it lacks math. I don't see that as a major problem. The way I see
>it, the blog post is a paradox, just like the twin paradox or Bell's
>spaceship paradox, both of which are described in words, without math.
>I'm confident there's a simple solution, also describable in words, ...
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Author: heiwosheiwos Date: May 2, 2008 14:10
On May 2, 7:30Â am, Oh No charlesfrancis.wanadoo.co.uk> wrote:> Thus spake heiwos gmail.com>
>
>
>>>I've come across a blog post that attempts to show that general
>>relativity (GR) contradicts itself about black holes. No, I didn't
>>write it so please don't lambaste me. I just want to know what's wrong
>>with it. I hope this isn't yet another group where not even an
>>imagined problem with mainstream physics can be discussed. I hope the
>>charter isn't a cruel trick.
>
>>There's been some discussion about the blog (note I didn't start it)
>>in another forum. You can find both the blog (called "On Cosmology")
>>and the discussion thread (at scienceforums) by googling for "No Black
>>Holes (General Relativity Contradicts Itself)" (put within double
>>quotes). I'd put the links here but Google Groups doesn't allow that
>>for some reason.
>
>>The best problem about the blog they've come up with in the thread is ...
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Author: Oh NoOh No Date: May 2, 2008 21:10
Thus spake heiwos gmail.com>>On May 2, 7:30Â am, Oh No charlesfrancis.wanadoo.co.uk> wrote:>> Thus spake heiwos gmail.com>
>>
>> - Show quoted text ->
>I don't see the problem you're seeing. Y is given to be an
>"infinitesimally small (in spacetime) freely falling frame that is
>falling through the horizon of a black hole". It is not given that the...
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Author: heiwosheiwos Date: May 3, 2008 14:10
On May 2, 10:05 pm, Oh No charlesfrancis.wanadoo.co.uk> wrote:> Thus spake heiwos gmail.com>
>>>On May 2, 7:30 am, Oh No charlesfrancis.wanadoo.co.uk> wrote:>>> Thus spake heiwos gmail.com>>
>>> - Show quoted text -
>
> [deleted link so I could post]
>
>
>
>>I don't see the problem you're seeing. Y is given to be an
>>"infinitesimally small (in spacetime) freely falling frame that is
>>falling through the horizon of a black hole". It is not given that the
>>tidal force in Y is measurable, so that's not an issue. Yes, the
>>escaping particle must move with respect to Y, but the paradox doesn't
>>claim otherwise. The point of the paradox is that the particle must
>>move relative the *ball*, or any other body in Y that is below the
>>horizon (in whole or partly), and that's a law of physics that doesn't ...
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Author: heiwosheiwos Date: May 3, 2008 17:11
On May 2, 10:05Â pm, Oh No charlesfrancis.wanadoo.co.uk> wrote:> Â Thus spake heiwos gmail.com>
>>>On May 2, 7:30Â am, Oh No charlesfrancis.wanadoo.co.uk> wrote:>>> Thus spake heiwos gmail.com>>
>>> - Show quoted text -
>
> re[link deleted so I can post]
>
>
>
>>I don't see the problem you're seeing. Y is given to be an
>>"infinitesimally small (in spacetime) freely falling frame that is
>>falling through the horizon of a black hole". It is not given that the
>>tidal force in Y is measurable, so that's not an issue. Yes, the
>>escaping particle must move with respect to Y, but the paradox doesn't
>>claim otherwise. The point of the paradox is that the particle must
>>move relative the *ball*, or any other body in Y that is below the
>>horizon (in whole or partly), and that's a law of physics that doesn't ...
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Author: Oh NoOh No Date: May 4, 2008 01:42
Thus spake heiwos gmail.com>>On May 2, 10:05Â pm, Oh No charlesfrancis.wanadoo.co.uk> wrote:>> Â Thus spake heiwos gmail.com>
>>>>>On May 2, 7:30Â am, Oh No charlesfrancis.wanadoo.co.uk> wrote:>>>> Thus spake heiwos gmail.com>>>
>>>> - Show quoted text -
>>
>> re[link deleted so I can post]
>>
>>
>>
>>>I don't see the problem you're seeing. Y is given to be an
>>>"infinitesimally small (in spacetime) freely falling frame that is
>>>falling through the horizon of a black hole". It is not given that the
>>>tidal force in Y is measurable, so that's not an issue. Yes, the
>>>escaping particle must move with respect to Y, but the paradox doesn't
>>>claim otherwise. The point of the paradox is that the particle must
>>>move relative the *ball*, or any other body in Y that is below the ...
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Author: Oh NoOh No Date: May 4, 2008 02:30
Thus spake heiwos gmail.com>>> To address the paradox specifically, the link states
>>
>> According to GR, all objects below a horizon inexorably fall until they
>> reach the black hole’s singularity.
>>
>> But this is not true. GR only says this about objects which have fallen
>> in to the event horizon.
>>
>> The paradox confuses the description of what happens in Schwarzschild
>> coordinates, from the point of view of a distant observer outside the
>> hole, with what happens in inertial coordinates in the vicinity of the
>> hole. Objects cannot escape the hole from the point of view of the
>> distant observer, but this does not mean that there are no geodesic
>> paths coming out of the hole.
>>
>> Indeed, GR tells us that for a freely falling observer, there is nothing
>> particularly unusual in the region where he crosses the event horizon.
>> For a large enough hole, tidal forces are not even particularly extreme.
>> For an inertial frame straddling the horizon, particles can in principle ...
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Author: heiwosheiwos Date: May 4, 2008 08:50
On May 4, 3:26 am, Oh No charlesfrancis.wanadoo.co.uk> wrote:> Thus spake heiwos gmail.com>
>
>
>
>
>>>> To address the paradox specifically, the link states
>
>>> According to GR, all objects below a horizon inexorably fall until they
>>> reach the black hole’s singularity.
>
>>> But this is not true. GR only says this about objects which have fallen
>>> in to the event horizon.
>
>>> The paradox confuses the description of what happens in Schwarzschild
>>> coordinates, from the point of view of a distant observer outside the
>>> hole, with what happens in inertial coordinates in the vicinity of the
>>> hole. Objects cannot escape the hole from the point of view of the
>>> distant observer, but this does not mean that there are no geodesic ...
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