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Patrick Elliott <sel### [at] npgcable com> wrote:
> guy that
> concluded that black holes *would* give off some radiation, and was
> proven right
I don't think that's correct.
"However, the existence of Hawking radiation has never been observed."
"Under experimentally achievable conditions for gravitational systems
this effect is too small to be observed."
http://en.wikipedia.org/wiki/Hawking_radiation
> How do
> you get denser than that, even if you reduce the particles to
> sub-particles, like quarks and muons?
Matter degenerates under that much gravity. They are not "particles"
anymore.
Besides, it doesn't really matter what happens to them. You would have
to prove that there exists a phenomenon or force in physics which makes
matter overcome the gravity and stops it from collapsing into a singularity
inside a black hole. I don't think any such phenomenon or force has been
observed or even plausibly conjectured.
> But, its still a question to physicists. There has to be a finite size
> for distance *period*, as with time. If you don't have those, time
> couldn't pass, and distance could never be crossed.
What does "finite size for distance, as with time" even mean?
> But, we can't
> observe the result, to see if that is true, so there *may* be a finite
> "density", beyond which you can't get any more compact, no matter how
> much gravity you throw at it.
You would need to explain what stops the matter from collapsing into a
singularity. It certainly cannot be a physical force.
--
- Warp
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Jim Henderson <nos### [at] nospamcom> wrote:
> On Wed, 21 Jul 2010 21:10:04 -0400, John VanSickle wrote:
> >> Another curious things is that many creationists seem to think that
> >> they
> >> know what "evolution" is better than evolutionists themselves.
> >
> > Which is the flip side of atheists who claim to know more about
> > theological topics than believers do.
> Well, not really; a fair number of the creationists reject scientific
> principles. Atheists tend to know a lot more about theistic religions
> than those who practice them, IME, because they've often been raised in
> one and then decided it's pants after years of careful study and
> questioning - questioning that *often* is answered with "don't ask those
> kinds of questions!"
There are certainly tons of atheists (a term which I'm using in a very
broad sense here) who have all kinds of misconceptions about the Bible and
the christian dogma, and which are quite easy to prove wrong, and which,
basically, make themselves as foolish with their misconceptions as many
creationists with their misconceptions about science.
On the other hand, there *are* many atheists who do know the Bible better
than most christians do, who do know which arguments against the Bible are
invalid (because they stem from prejudice and misinterpretation of the text
by ignoring its context), and they also know which parts of the Bible (which
many creationists interpret literally) truly don't stand too much scrutiny
in the face of scientific evidence. Of course these are the minority, in
my experience.
--
- Warp
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On Thu, 22 Jul 2010 12:18:05 -0400, Warp wrote:
> Patrick Elliott <sel### [at] npgcablecom> wrote:
>> guy that
>> concluded that black holes *would* give off some radiation, and was
>> proven right
>
> I don't think that's correct.
>
> "However, the existence of Hawking radiation has never been observed."
>
> "Under experimentally achievable conditions for gravitational systems
> this effect is too small to be observed."
>
> http://en.wikipedia.org/wiki/Hawking_radiation
http://arxivblog.com/?p=300
Essentially, this is a simulated observation that demonstrates the theory
of Hawking radiation is sound.
Jim
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On 7/22/2010 9:18 AM, Warp wrote:
> Patrick Elliott<sel### [at] npgcablecom> wrote:
>> guy that
>> concluded that black holes *would* give off some radiation, and was
>> proven right
>
> I don't think that's correct.
>
> "However, the existence of Hawking radiation has never been observed."
>
> "Under experimentally achievable conditions for gravitational systems
> this effect is too small to be observed."
>
> http://en.wikipedia.org/wiki/Hawking_radiation
>
Actually, this is only partly correct. There has been no "direct"
observation of it, but there has been indirect. But, technically, since
its so damn small, this would be correct. Mind, if you don't have it,
then you have to come up with something else to explain radiation from a
block hole, where there shouldn't be any, and that *has* been seen.
>> How do
>> you get denser than that, even if you reduce the particles to
>> sub-particles, like quarks and muons?
>
> Matter degenerates under that much gravity. They are not "particles"
> anymore.
>
> Besides, it doesn't really matter what happens to them. You would have
> to prove that there exists a phenomenon or force in physics which makes
> matter overcome the gravity and stops it from collapsing into a singularity
> inside a black hole. I don't think any such phenomenon or force has been
> observed or even plausibly conjectured.
>
>> But, its still a question to physicists. There has to be a finite size
>> for distance *period*, as with time. If you don't have those, time
>> couldn't pass, and distance could never be crossed.
>
> What does "finite size for distance, as with time" even mean?
>
>> But, we can't
>> observe the result, to see if that is true, so there *may* be a finite
>> "density", beyond which you can't get any more compact, no matter how
>> much gravity you throw at it.
>
> You would need to explain what stops the matter from collapsing into a
> singularity. It certainly cannot be a physical force.
>
If its not particles, then what? Energy? Oh, wait, energy is still some
sort of particle, as near as we can come up with. Mind, it might not be,
if you go all the way down to String Theory, but that is just pure math,
it has yet to come up with math that correctly matches the observed
universe, and at best, *may* describe a near infinite list of "possible"
universes, of which ours is just one in gazzillions (which makes finding
the right math to match it, never mind verify that String Theory is
right, worse odds than winning the lotto).
In any case, no, the problem here is that you have to present a
plausible thing to "be" there, if you don't have particles, given that
even breaking up something like an electron gives you... more particles.
Again, its presupposing what is there, based on what needs to be, for
the math to come out right. It doesn't prove that the math *is* right,
in those conditions, or there is some basic limit, just like with
distance and travel, over time. There is simply the assumption that
there isn't one.
But, like I said, until he publishes, all we have is the assertion that
its not happening, combined with the embarrassing fact that certain
observations are not explained, by other means, without the prior
Hawking's Radition.
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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On Thu, 22 Jul 2010 12:32:50 -0400, Warp wrote:
> Jim Henderson <nos### [at] nospamcom> wrote:
>> On Wed, 21 Jul 2010 21:10:04 -0400, John VanSickle wrote:
>
>> >> Another curious things is that many creationists seem to think
>> >> that they
>> >> know what "evolution" is better than evolutionists themselves.
>> >
>> > Which is the flip side of atheists who claim to know more about
>> > theological topics than believers do.
>
>> Well, not really; a fair number of the creationists reject scientific
>> principles. Atheists tend to know a lot more about theistic religions
>> than those who practice them, IME, because they've often been raised in
>> one and then decided it's pants after years of careful study and
>> questioning - questioning that *often* is answered with "don't ask
>> those kinds of questions!"
>
> There are certainly tons of atheists (a term which I'm using in a very
> broad sense here) who have all kinds of misconceptions about the Bible
> and the christian dogma, and which are quite easy to prove wrong, and
> which, basically, make themselves as foolish with their misconceptions
> as many creationists with their misconceptions about science.
Oh, sure - those who are *active* atheists, though (as compared to those
who just "don't care" - which is more agnosticism than atheism IIRC) do
tend to have studied a lot more than the average practitioner of a
theistic religion.
> On the other hand, there *are* many atheists who do know the Bible
> better
> than most christians do, who do know which arguments against the Bible
> are invalid (because they stem from prejudice and misinterpretation of
> the text by ignoring its context), and they also know which parts of the
> Bible (which many creationists interpret literally) truly don't stand
> too much scrutiny in the face of scientific evidence. Of course these
> are the minority, in my experience.
If you count everyone who's just inactive in a religion as an atheist,
then you're correct. When I talk about atheists in this context, though,
I'm talking about those who are *actively* atheistic - and not the people
who just haven't been to church in a while or who perhaps have doubts.
Jim
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Warp wrote:
> Matter degenerates under that much gravity. They are not "particles"
> anymore.
Err, what are they, then?
> Besides, it doesn't really matter what happens to them. You would have
> to prove that there exists a phenomenon or force in physics which makes
> matter overcome the gravity and stops it from collapsing into a singularity
> inside a black hole. I don't think any such phenomenon or force has been
> observed or even plausibly conjectured.
I would think Pauli exclusion would be a possibility. Or something like the
quantumness of spacetime. Can you actually fit multiple particles into one
plank-length of space?
> You would need to explain what stops the matter from collapsing into a
> singularity. It certainly cannot be a physical force.
I think first you have to define what you mean by a "singularity", then by a
"force", given that gravity isn't a force per se.
I think once you wander outside the area where the math actually is known to
work, you need some actual experimental evidence to base conclusions on. I
don't know that it's valid to say "that must behave *this* way, because
otherwise we'd divide by zero" (or "because we divide by zero"). The math
only summarizes what we know of physics. It doesn't define how physics works.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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On 7/21/2010 6:10 PM, John VanSickle wrote:
> Warp wrote:
>> Warp <war### [at] tagpovrayorg> wrote:
>>> Why do creationists (with which I'm referring to certain specific dogmas
>>> rather than "christians" or "believers" in general) continuously confuse
>>> two completely different and separate fields of science, namely
>>> astronomy
>>> and biology?
>>
>> Another curious things is that many creationists seem to think that they
>> know what "evolution" is better than evolutionists themselves.
>
> Which is the flip side of atheists who claim to know more about
> theological topics than believers do.
>
> It is certainly true that there are lots of people in both camps who
> believe and know only what their accepted authorities have told them
> about either topic.
>
The funny thing on that is, the average "believer" I know has maybe read
20% of the Bible, almost **nothing** on the history tied to the time
periods described in it (with possible exception of texts designed to
ignore things that don't fit in with the "official" dogma), where as
most atheists have read more than half of it, or the entire thing, more
than once, and at least 1-2 books on the history of some of the periods,
*and* more than a few books on other religions. The other thing is, like
95% of atheists used to be believers, probably 20% of them where
Evangelical, before concluding it was all gibberish, and another 2% or
so where ***actually priests*** at one point in time.
By contrast, with the exception of a few that, when you examine their
claims, are obviously lying, or didn't understand what they read in the
first place, or where **already** looking for a different answer, so
didn't *ever* accept the scientific evidence, there is maybe 1 biologist
*ever* that has converted from atheist to some form of deism, that I
know of, and he was medically ill, being pestered by "helpful"
Evangelicals at the time, and suffering mid-stage dementia.
Hell yes, a lot of atheists have a better idea than the believers what
their "theology" says...
>> A very typical argument between a (young-earth) creationist and an
>> evolutionist goes like: "Can you give me even one single example of
>> evolution having been observed?" "Yes, there's for example xyz."
>> "That's not evolution."
>>
>> Wait, now creationists define what "evolution" means and are, basically,
>> claiming that evolutionists don't even know what it really means?
>
> Differing definitions of evolution at work. In the broadest sense, it
> refers to any change over time in the variety of life, which is
> observable. Creationists use the term to refer to something more
> specific, such as the gradual change of one form of life into a
> significantly different form (such as the transition from insectivores
> into carnivores).
>
> Regards,
> John
Or, they completely jump the shark, and start babbling about dogs giving
birth to cats, in one single generation. I.e., miracles being a
necessity for evolution to work... lol
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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On 7/22/2010 9:32 AM, Warp wrote:
> Jim Henderson<nos### [at] nospamcom> wrote:
>> On Wed, 21 Jul 2010 21:10:04 -0400, John VanSickle wrote:
>
>>>> Another curious things is that many creationists seem to think that
>>>> they
>>>> know what "evolution" is better than evolutionists themselves.
>>>
>>> Which is the flip side of atheists who claim to know more about
>>> theological topics than believers do.
>
>> Well, not really; a fair number of the creationists reject scientific
>> principles. Atheists tend to know a lot more about theistic religions
>> than those who practice them, IME, because they've often been raised in
>> one and then decided it's pants after years of careful study and
>> questioning - questioning that *often* is answered with "don't ask those
>> kinds of questions!"
>
> There are certainly tons of atheists (a term which I'm using in a very
> broad sense here) who have all kinds of misconceptions about the Bible and
> the christian dogma, and which are quite easy to prove wrong, and which,
> basically, make themselves as foolish with their misconceptions as many
> creationists with their misconceptions about science.
>
Willing to bet that most of those "misconceptions" are nothing of the
sort, but rather preconceptions, arising out of their own experience
with believers, including those they grew up with, who actually
***did*** think those things where in the Bible. Oh, and then there is
all the stuff that is correct vis a vie the Bible, if you read it "in
context", or "literally", or "in terms of the time period and beliefs
common then", but bare no resemblance **at all** to the cherry picked,
ultra-liberal (but don't dare say that in some circles), white washed
version that many modern Christians "think" their Bible has in it, on
the basis of sermons that, if they are lucky, contain less than 10% of
the total contents, while the other 90% is quietly classed as, "Not
relevant to anything I ever preach about", and swept under the nearest
alter cloth.
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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3D Content, and 3D Software at DAZ3D!</A>
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On 7/22/2010 10:07 AM, Darren New wrote:
> Warp wrote:
>> Matter degenerates under that much gravity. They are not "particles"
>> anymore.
>
> Err, what are they, then?
>
>> Besides, it doesn't really matter what happens to them. You would have
>> to prove that there exists a phenomenon or force in physics which makes
>> matter overcome the gravity and stops it from collapsing into a
>> singularity
>> inside a black hole. I don't think any such phenomenon or force has been
>> observed or even plausibly conjectured.
>
> I would think Pauli exclusion would be a possibility. Or something like
> the quantumness of spacetime. Can you actually fit multiple particles
> into one plank-length of space?
>
>> You would need to explain what stops the matter from collapsing into a
>> singularity. It certainly cannot be a physical force.
>
> I think first you have to define what you mean by a "singularity", then
> by a "force", given that gravity isn't a force per se.
>
> I think once you wander outside the area where the math actually is
> known to work, you need some actual experimental evidence to base
> conclusions on. I don't know that it's valid to say "that must behave
> *this* way, because otherwise we'd divide by zero" (or "because we
> divide by zero"). The math only summarizes what we know of physics. It
> doesn't define how physics works.
>
This is one reason why singularity is a problem. You throw out every
equation you "do" have about how things work, because, "They don't work
there.", only.. then you have to ask why, given things like the
"multiple particles in a Plank Length" issue, which the same math says
shouldn't happen, even *in* a black hole. If you conclude that, like a
lot of math, there is a point where it just won't apply, then you only
have to deal with "one" equation being wrong at that level of mass, not
***every*** equation in physics, except the one telling you a
singularity formed. Which seems more absurd, or just less complicated?
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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Jim Henderson wrote:
> Essentially, this is a simulated observation that demonstrates the theory
> of Hawking radiation is sound.
So, what you're saying is, Hawking used math to predict hairy black holes.
Carusotto took the same math applied to a Bose condensate, and predicted
you'd see the same sort of effect from it, without actually creating a Bose
condensate in the laboratory.
And this shows that black holes emit radiation?
Hey, my math says I can build a Wells-type time machine. And look, they even
made a movie of it, so that proves it would work!
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Patrick Elliott wrote:
> If its not particles, then what? Energy? Oh, wait, energy is still some
> sort of particle, as near as we can come up with.
Well, that's sort of what the LHC is looking for, so I'm pretty sure the
jury is still out on that one.
> combined with the embarrassing fact that certain
> observations are not explained, by other means, without the prior
> Hawking's Radition.
Like what, out of curiousity. I wasn't aware we'd managed to find a black
hole small enough that the hawking radiation effect would work.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Patrick Elliott wrote:
> This is one reason why singularity is a problem.
I'm sorry, but your writing is so bad, I can't even figure out what you're
trying to say.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Patrick Elliott <sel### [at] npgcablecom> wrote:
> If its not particles, then what? Energy? Oh, wait, energy is still some
> sort of particle, as near as we can come up with.
Energy is quantized in normal circumstances. However, at a singularity,
if they exist, all physics break up. There's nothing to say that energy
is still quantized at a singularity. (The *amount* of energy in a singularity
might be a multiple of an energy quantum, but that doesn't mean that the
energy is subdivided into quantized parts in there.)
> In any case, no, the problem here is that you have to present a
> plausible thing to "be" there, if you don't have particles, given that
> even breaking up something like an electron gives you... more particles.
Matter/energy degenerates under such enormous gravity, forming something
which doesn't happen normally elsewhere. It retains certain properties
(such as mass) because energy cannot be destroyed nor created, but its
physiology may be completely different than normally.
It's the same as what happened in the first moments of the Big Bang.
There were no particles until later.
> Again, its presupposing what is there, based on what needs to be, for
> the math to come out right. It doesn't prove that the math *is* right,
> in those conditions, or there is some basic limit, just like with
> distance and travel, over time. There is simply the assumption that
> there isn't one.
Well, as long as you can't present a plausible alternative, I'd say
the Occam's Razor applies...
--
- Warp
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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > Matter degenerates under that much gravity. They are not "particles"
> > anymore.
> Err, what are they, then?
How should I know? I'm not an astrophysicist.
> > Besides, it doesn't really matter what happens to them. You would have
> > to prove that there exists a phenomenon or force in physics which makes
> > matter overcome the gravity and stops it from collapsing into a singularity
> > inside a black hole. I don't think any such phenomenon or force has been
> > observed or even plausibly conjectured.
> I would think Pauli exclusion would be a possibility.
That kicks in up to a certain point. It's what happens in neutron star
cores, where particles are as close to each other as they can be without
breaking the Pauli exclusion principle.
However, even this exclusion principle doesn't exert an infinite force
on particles, and if the gravity is larger than the critical limit, the
matter just collapses and there's nothing to stop it. (AFAIK according to
the relativistic equations you would need literally an infinitely strong
force to keep matter inside the event horizon from falling into the
singularity. Thus no kind of non-zero-sized shape can be maintained in
there.)
> Or something like the
> quantumness of spacetime. Can you actually fit multiple particles into one
> plank-length of space?
Since there is currently no unifying quantum theory of gravity, nothing
definitive can be said about that, I think.
> > You would need to explain what stops the matter from collapsing into a
> > singularity. It certainly cannot be a physical force.
> I think first you have to define what you mean by a "singularity", then by a
> "force", given that gravity isn't a force per se.
> I think once you wander outside the area where the math actually is known to
> work, you need some actual experimental evidence to base conclusions on. I
> don't know that it's valid to say "that must behave *this* way, because
> otherwise we'd divide by zero" (or "because we divide by zero"). The math
> only summarizes what we know of physics. It doesn't define how physics works.
The math seems to work everywhere else, so without evidence of the
contrary the simpler assumption is that it works everywhere.
--
- Warp
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Patrick Elliott <sel### [at] npgcablecom> wrote:
> The funny thing on that is, the average "believer" I know has maybe read
> 20% of the Bible, almost **nothing** on the history tied to the time
> periods described in it (with possible exception of texts designed to
> ignore things that don't fit in with the "official" dogma), where as
> most atheists have read more than half of it, or the entire thing, more
> than once, and at least 1-2 books on the history of some of the periods,
> *and* more than a few books on other religions. The other thing is, like
> 95% of atheists used to be believers, probably 20% of them where
> Evangelical, before concluding it was all gibberish, and another 2% or
> so where ***actually priests*** at one point in time.
I'm wondering if you are talking about Americans there.
Here the majority of people are atheists, and from them, the vast majority
have always been. And only a very, very small percentage have ever even
opened the Bible. (Yes, while in the US people are by default christians,
atheism being the rare exception, here people are by default secular,
religion being the exception. It might be hard for an American to fathom,
but it is really a bit surprising if someone claims being a believer, as
the assumed status quo is being secular. I suppose some American atheists
could call this a paradise of sorts.)
--
- Warp
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>> Matter degenerates under that much gravity. They are not "particles"
>>> anymore.
>
>> Err, what are they, then?
>
> How should I know? I'm not an astrophysicist.
Why do you think they aren't particles, then?
> However, even this exclusion principle doesn't exert an infinite force
> on particles,
I'm not sure that's true - the probability in the math that two
(appropriate) particles occupy the same location is indeed zero. Now, what
happens when there isn't any space for them not to be apart, I'm not sure.
> and if the gravity is larger than the critical limit, the
> matter just collapses and there's nothing to stop it. (AFAIK according to
> the relativistic equations you would need literally an infinitely strong
> force to keep matter inside the event horizon from falling into the
> singularity. Thus no kind of non-zero-sized shape can be maintained in
> there.)
Yeah. I'm not arguing that any one thing happens or doesn't. I'm just trying
to figure out why people seem to be asserting that we know what happens in
the middle of a singularity (where the math doesn't apply or conflicts with
other theories that have just as much or more evidence in their favor).
>> Or something like the
>> quantumness of spacetime. Can you actually fit multiple particles into one
>> plank-length of space?
>
> Since there is currently no unifying quantum theory of gravity, nothing
> definitive can be said about that, I think.
Right. So applying relativity where we already know it doesn't apply doesn't
seem to be supportable, scientifically speaking.
> The math seems to work everywhere else, so without evidence of the
> contrary the simpler assumption is that it works everywhere.
Well, no, it doesn't work everywhere else.
That's how we know QED and GR aren't compatible and why we need to find a
quantum theory of gravity. GR does *not* work at quantum scales. It assumes
space is continuous, and QED only works if you assume space is
discontinuous. (Or, rather, QED gives nonsensical answers if you calculate
it assuming that indefinitely small distances in space are possible.)
It's also the case that when you get down to zero size, if you mash
everything into a single point, then you start violating the duality
principle (if I understand correctly) as well as a whole bunch of symmetry
laws, which is why there's now all kinds of talk about holographic
information on the surface of black holes and such.
It's like saying "Well, arctangent works for every other angle. Why wouldn't
we assume it works for 90 degrees?" Well, that's why it's called a
"singularity". There's a point in the math where the math does *not* work,
precisely because you wind up with equations with zeros in the denominator.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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On Thu, 22 Jul 2010 10:37:06 -0700, Darren New wrote:
> Jim Henderson wrote:
>> Essentially, this is a simulated observation that demonstrates the
>> theory of Hawking radiation is sound.
>
> So, what you're saying is, Hawking used math to predict hairy black
> holes. Carusotto took the same math applied to a Bose condensate, and
> predicted you'd see the same sort of effect from it, without actually
> creating a Bose condensate in the laboratory.
>
> And this shows that black holes emit radiation?
>
> Hey, my math says I can build a Wells-type time machine. And look, they
> even made a movie of it, so that proves it would work!
<shrug> I just remembered hearing that it was beyond mere theory.
Jim
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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > Darren New <dne### [at] sanrrcom> wrote:
> >> Warp wrote:
> >>> Matter degenerates under that much gravity. They are not "particles"
> >>> anymore.
> >
> >> Err, what are they, then?
> >
> > How should I know? I'm not an astrophysicist.
> Why do you think they aren't particles, then?
Because you can't have a huge bunch of particles in a space of zero
volume. Hence if all the mass is in a singularity, it cannot be in the
form of particles, but something else completely (basically something
that cannot be described with current knowledge of physics).
(Of course I'm assuming here that singularities do exist. It's possible
that reality is different and they don't.)
> > and if the gravity is larger than the critical limit, the
> > matter just collapses and there's nothing to stop it. (AFAIK according to
> > the relativistic equations you would need literally an infinitely strong
> > force to keep matter inside the event horizon from falling into the
> > singularity. Thus no kind of non-zero-sized shape can be maintained in
> > there.)
> Yeah. I'm not arguing that any one thing happens or doesn't. I'm just trying
> to figure out why people seem to be asserting that we know what happens in
> the middle of a singularity (where the math doesn't apply or conflicts with
> other theories that have just as much or more evidence in their favor).
People don't claim to know what happens in the singularity. They claim that
the equations say something about what happens *outside* the singularity
(and that "something" is, basically, "there can't be anything inside the
event horizon and outside the singularity, hence the only possible place
where everything must be is in the singularity, because that's where all
the space-time geodesics are pointing to").
> >> Or something like the
> >> quantumness of spacetime. Can you actually fit multiple particles into one
> >> plank-length of space?
> >
> > Since there is currently no unifying quantum theory of gravity, nothing
> > definitive can be said about that, I think.
> Right. So applying relativity where we already know it doesn't apply doesn't
> seem to be supportable, scientifically speaking.
Relativity cannot be applied to the singularity itself, but it can be
applied to the space between the event horizon and the singularity. (It's
all really weird there, and greatly complicated by things like rotation
and electric charge, but calculable.)
> It's also the case that when you get down to zero size, if you mash
> everything into a single point, then you start violating the duality
> principle (if I understand correctly) as well as a whole bunch of symmetry
> laws, which is why there's now all kinds of talk about holographic
> information on the surface of black holes and such.
If GR breaks at the singularity, who is to say that QM doesn't?
Maybe information *is* destroyed at the singularity? After all, it's
pretty weird in there (being of zero size and all).
--
- Warp
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Jim Henderson wrote:
> <shrug> I just remembered hearing that it was beyond mere theory.
Not according to *that* paper. :-)
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Warp wrote:
> Because you can't have a huge bunch of particles in a space of zero
> volume.
The math for QM doesn't work out (so I've heard) if you assume particles
aren't points.
> Hence if all the mass is in a singularity, it cannot be in the
> form of particles, but something else completely (basically something
> that cannot be described with current knowledge of physics).
That's fair. But I would more say "we don't know if they're still particles
or something else" than I would say "we know they can't be particles because
the math says there's zero space at the bottom of the well."
> (Of course I'm assuming here that singularities do exist. It's possible
> that reality is different and they don't.)
Yeah, that's really the only assumption I'm challenging. Lots of folks on
this thread are making assertions about what actually happens in places
where, by definition, you cannot observe what actually happens. :-)
> People don't claim to know what happens in the singularity. They claim that
> the equations say something about what happens *outside* the singularity
> (and that "something" is, basically, "there can't be anything inside the
> event horizon and outside the singularity, hence the only possible place
> where everything must be is in the singularity, because that's where all
> the space-time geodesics are pointing to").
Sure. Except it's a singularity. There's a discontinuity in the mathematics
there. That's why it has that name. And the theories of gravity don't work
if space isn't continuous, and the theories of really small stuff don't work
if the space isn't discontinuous. So ... I think it's safe to say "we don't
know."
And, actually, the whole thing with the "holographic universe" bit is that
stuff really doesn't necessarily disappear when it goes into the black hole.
> Relativity cannot be applied to the singularity itself, but it can be
> applied to the space between the event horizon and the singularity. (It's
> all really weird there, and greatly complicated by things like rotation
> and electric charge, but calculable.)
*Assuming* that space is continuous. But if there's a lower limit on "the
shortest distance" that isn't zero, then GR breaks down. And QED seems to
suggest there is such a limit, because QED breaks down when you assume the
shortest distance *is* zero.
> If GR breaks at the singularity, who is to say that QM doesn't?
We know it does, *if* you assume GR. That's exactly why people are looking
for a quantum version of GR. Because if you assume gravity can compress
things down arbitrarily small, then QED gives infinite energies for every
interaction, including those outside the event horizon.
> Maybe information *is* destroyed at the singularity? After all, it's
> pretty weird in there (being of zero size and all).
That would violate all sorts of symmetry laws. That's why they think it
doesn't happen. You lose all kinds of things like conservation of charge, as
well as (if I recall right) conservation of some properties that GR assumes
in its formulation, like conservation of momentum.
Of course, obviously something is wrong with the theories. We already know
that. That's why people are looking at string theory and other GUTs. It's
exactly these border conditions (infinite gravity, zero size) where the
theories break down. So I'm not convinced anyone can confidently assert what
*actually* happens, vs what the math implies should happen if the math is
still isomorphic with reality under those circumstances.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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On Thu, 22 Jul 2010 15:18:50 -0400, Warp wrote:
> Because you can't have a huge bunch of particles in a space of zero
> volume.
I'm not a physicist (though I know a few people who are), but ISTR
reading/hearing that a 'singularity' isn't defined as a space with zero
volume. It's a very densely packed collection of matter, but not with
zero volume.
Jim
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On Thu, 22 Jul 2010 12:37:02 -0700, Darren New wrote:
> Jim Henderson wrote:
>> <shrug> I just remembered hearing that it was beyond mere theory.
>
> Not according to *that* paper. :-)
It was the first hit that I ran across, and it sounded vaguely familiar,
but probably was something else. ;-)
Jim
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Am 22.07.2010 21:46, schrieb Darren New:
>> Hence if all the mass is in a singularity, it cannot be in the
>> form of particles, but something else completely (basically something
>> that cannot be described with current knowledge of physics).
>
> That's fair. But I would more say "we don't know if they're still
> particles or something else" than I would say "we know they can't be
> particles because the math says there's zero space at the bottom of the
> well."
An interesting thought in this context is that the mass will never
actually reach the singularity state anyway as long as the universe
exists, due to the extreme warping of space-time.
>> People don't claim to know what happens in the singularity. They claim
>> that
>> the equations say something about what happens *outside* the singularity
>> (and that "something" is, basically, "there can't be anything inside the
>> event horizon and outside the singularity, hence the only possible place
>> where everything must be is in the singularity, because that's where all
>> the space-time geodesics are pointing to").
I think there's a flaw in here, too: The event horizon itself is subject
to relativity as well. An observer approaching the black hole in free
fall will witness the event horizon to "dent in" in front of him, even
when he himself has already passed the event horizon as witnessed from a
far-away observer.
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Jim Henderson <nos### [at] nospamcom> wrote:
> I'm not a physicist (though I know a few people who are), but ISTR
> reading/hearing that a 'singularity' isn't defined as a space with zero
> volume. It's a very densely packed collection of matter, but not with
> zero volume.
According to GR you would need an infinite amount of energy to maintain
a shape with non-zero volume. Obviously there isn't an infinite amount of
energy inside a black hole.
--
- Warp
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Kevin Wampler <wam### [at] uwashingtonedu> wrote:
> I'm not sure I see anything in this quote which implies that the big
> bang is part of evolution. The most natural interpretation seems to be
> that "evolutionist" is used as a blanket term which can be used as a
> label for one who holds a set of related viewpoints of which evolution
> need only be a part.
Btw, here's a more concrete example of "evolution" (literally "evolution",
not "evolutionists") being equated to abiogenesis:
http://www.youtube.com/watch?v=FZFG5PKw504
"Evolution teaches that energy, such as lightning or heat, plus matter
can, occassionally, create new life."
Nope. Evolution teaches no such thing.
(The rest of the video is quite hilarious. Basically they are disproving
what science itself disproved in the 17th century...)
--
- Warp
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Darren New wrote:
> Yeah, that's really the only assumption I'm challenging.
Interestingly, I just stumbled across this, without even looking for it.
http://www.dailygalaxy.com/my_weblog/2010/07/did-time-exist-before-the-big-bang.html
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Am 22.07.2010 22:17, schrieb Jim Henderson:
> On Thu, 22 Jul 2010 15:18:50 -0400, Warp wrote:
>
>> Because you can't have a huge bunch of particles in a space of zero
>> volume.
>
> I'm not a physicist (though I know a few people who are), but ISTR
> reading/hearing that a 'singularity' isn't defined as a space with zero
> volume. It's a very densely packed collection of matter, but not with
> zero volume.
Actually, AFAIK a "singularity" is defined as any condition in which the
formulae of a theory don't give any meaningful answer.
In GR, you can pack matter arbitrarily dense in any non-zero volume
without the formulae breaking down, so no - I guess you're wrong.
However, you may be not so far off the mark regarding black holes:
AFAIK, those indeed typically have a non-zero (though ever shrinking)
volume, as in order to form a true singularity you'd need a neatly
symmetric collapse.
Thus, the problem with black holes is probably not the singularity /per
se/: To me it looks like that's a purely academic issue because there
bloody likely aren't any such beasts out there in reality. Instead, the
problem with black holes is that ever-shrinking thing, which doesn't go
along well with QED's prediction of a lower bound on distances.
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Warp wrote:
> According to GR you would need an infinite amount of energy to maintain
> a shape with non-zero volume. Obviously there isn't an infinite amount of
> energy inside a black hole.
Interestingly, according to QM, you need an infinite amount of energy if two
particles can be zero distance from each other. And that is *exactly* the
problem.
http://en.wikipedia.org/wiki/Renormalization
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Jim Henderson <nos### [at] nospamcom> writes:
> Well, not really; a fair number of the creationists reject scientific
> principles. Atheists tend to know a lot more about theistic religions
> than those who practice them, IME, because they've often been raised in
> one and then decided it's pants after years of careful study and
> questioning - questioning that *often* is answered with "don't ask those
> kinds of questions!"
My experience is quite the opposite: The self-proclaimed atheists I've
interacted with often betray their lack of understanding of
religion. They sound far more like people who read books that are, for
lack of a better term, anti-religion, than from observation of the
world, or study of a religion.
They also had a terrible tendency to generalize: They see something
silly in one sect in one religion, and they generalize like
crazy.
Their rhetoric isn't helpful. They often ask religious people to defend
principles that those religious people don't always believe in, for
example. They didn't bother establishing whether the person they're
speaking to fits their mental model of a religious person. He merely
does, because he's religious.
No doubt, there are exceptions. As a few milder atheists are at pains to
point out: "Just as their are all kinds of religious folks, atheists are
not as monolithic as they seem. The vocal set just happen to be assholes."
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Jim Henderson <nos### [at] nospamcom> writes:
>> There are certainly tons of atheists (a term which I'm using in a very
>> broad sense here) who have all kinds of misconceptions about the Bible
>> and the christian dogma, and which are quite easy to prove wrong, and
>> which, basically, make themselves as foolish with their misconceptions
>> as many creationists with their misconceptions about science.
>
> Oh, sure - those who are *active* atheists, though (as compared to those
> who just "don't care" - which is more agnosticism than atheism IIRC) do
> tend to have studied a lot more than the average practitioner of a
> theistic religion.
Again, I disagree - perhaps you phrased it carelessly. The ones I spoke
of in my message are very much atheists, not agnostics.
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On Thu, 22 Jul 2010 19:59:44 -0700, Neeum Zawan wrote:
> Jim Henderson <nos### [at] nospamcom> writes:
>
>>> There are certainly tons of atheists (a term which I'm using in a
>>> very
>>> broad sense here) who have all kinds of misconceptions about the Bible
>>> and the christian dogma, and which are quite easy to prove wrong, and
>>> which, basically, make themselves as foolish with their misconceptions
>>> as many creationists with their misconceptions about science.
>>
>> Oh, sure - those who are *active* atheists, though (as compared to
>> those who just "don't care" - which is more agnosticism than atheism
>> IIRC) do tend to have studied a lot more than the average practitioner
>> of a theistic religion.
>
> Again, I disagree - perhaps you phrased it carelessly. The ones I spoke
> of in my message are very much atheists, not agnostics.
I think rather I didn't phrase it 'carelessly' but rather based on my own
experiences. What would YOU do?
Jim
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On 7/22/2010 11:02 AM, Warp wrote:
>> In any case, no, the problem here is that you have to present a
>> plausible thing to "be" there, if you don't have particles, given that
>> even breaking up something like an electron gives you... more particles.
>
> Matter/energy degenerates under such enormous gravity, forming something
> which doesn't happen normally elsewhere. It retains certain properties
> (such as mass) because energy cannot be destroyed nor created, but its
> physiology may be completely different than normally.
>
> It's the same as what happened in the first moments of the Big Bang.
> There were no particles until later.
>
Based on what? Observation? At best you can't say one is more plausible
than the other, and at worst, having to make up a whole set of
assumptions about how all the laws of physics differ in black holes *is*
a violation of Occam's Razor itself, imo. One extra rule, which fits
with known math involving non-black holes, or a whole different set,
which only matter after you get past the "edge", where you can't observe
if they are true or not anyway. Those seem to be the options, and there
is nothing that the later ones provide, in the way of useful
experiments, or even utility wise, which is "necessary" to explain
anything that can't be explained with standard physics, as long as you
allow for one equation having a special case, again, instead of dozens
of others.
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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On 7/22/2010 12:18 PM, Warp wrote:
> Darren New<dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>> Darren New<dne### [at] sanrrcom> wrote:
>>>> Warp wrote:
>>>>> Matter degenerates under that much gravity. They are not "particles"
>>>>> anymore.
>>>
>>>> Err, what are they, then?
>>>
>>> How should I know? I'm not an astrophysicist.
>
>> Why do you think they aren't particles, then?
>
> Because you can't have a huge bunch of particles in a space of zero
> volume. Hence if all the mass is in a singularity, it cannot be in the
> form of particles, but something else completely (basically something
> that cannot be described with current knowledge of physics).
>
> (Of course I'm assuming here that singularities do exist. It's possible
> that reality is different and they don't.)
>
Special pleading. That is all I have to say on that. If you don't get
them, you don't have to make up some *unknown*, and *undefined* thing
for matter to "be" when its in one.
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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On 7/22/2010 7:58 PM, Neeum Zawan wrote:
> They also had a terrible tendency to generalize: They see something
> silly in one sect in one religion, and they generalize like
> crazy.
>
> Their rhetoric isn't helpful. They often ask religious people to defend
> principles that those religious people don't always believe in, for
> example. They didn't bother establishing whether the person they're
> speaking to fits their mental model of a religious person. He merely
> does, because he's religious.
>
Problem with this is, while true, there is a fairly consistent "media"
trend on what kind of stuff people believe, and that 99% of believers
may not believe it doesn't help, if what they do believe is just as silly.
In any case, you cannot address a position you are not aware of, so you
address the ones you *are* aware of, which tend to be that presented by
the loudest, most annoying, incoherent, but visible, people.
But, even among the so called "worst", the basic position is that
religion has two forms. The first is, "I collect stamps, and I would
love to meet other people that collect stamps", variety, which you can
usually ignore, as long as some situation doesn't come up, in which
their stamps are threatened. The second is, "You MUST collect STAMPS,
anyone that DOESN'T is a horrible person, and everyone that says stamp
COLLECTING isn't interesting, NEVER MIND that its useless, or nuts, is
out to DESTROY our entire way of LIFE!!!" Sorry, but I know some of you
can't get html, so I can't add in the random colors and Comic Sans. ;)
In any case, its not possible to take on an issue, without doing "some"
level of generalizing. And, yeah, we do have some idiots on our side
that do it a bit too often.
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
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On 7/22/2010 11:23 AM, Warp wrote:
> Patrick Elliott<sel### [at] npgcablecom> wrote:
>> The funny thing on that is, the average "believer" I know has maybe read
>> 20% of the Bible, almost **nothing** on the history tied to the time
>> periods described in it (with possible exception of texts designed to
>> ignore things that don't fit in with the "official" dogma), where as
>> most atheists have read more than half of it, or the entire thing, more
>> than once, and at least 1-2 books on the history of some of the periods,
>> *and* more than a few books on other religions. The other thing is, like
>> 95% of atheists used to be believers, probably 20% of them where
>> Evangelical, before concluding it was all gibberish, and another 2% or
>> so where ***actually priests*** at one point in time.
>
> I'm wondering if you are talking about Americans there.
>
Bingo.
> Here the majority of people are atheists, and from them, the vast majority
> have always been. And only a very, very small percentage have ever even
> opened the Bible. (Yes, while in the US people are by default christians,
> atheism being the rare exception, here people are by default secular,
> religion being the exception. It might be hard for an American to fathom,
> but it is really a bit surprising if someone claims being a believer, as
> the assumed status quo is being secular. I suppose some American atheists
> could call this a paradise of sorts.)
>
Yes, well.. Doesn't stop Europeans and others from getting the same
class of wackos, often US funded, trying to push the same BS too.
Scarily, it seems to work in some places, to a degree. But, no. Probably
most Americans are fed up with it, and just as, generally, secular as
Europeans. What we have is a whole mass of false national pride, a near
total refusal to deal with anything that involves religion, an a larger
than acceptable percentage of people who ignore the fact that 99% of the
world, think they are nuts, in favor of crying "persecution", every time
someone tells them they can't demand people do something, in the name of
God, and have everyone cry, "Hallelujah!"
To these people, merely having a slightly different opinion about
Christianity is blasphemy and grounds for possible deportation (and they
have babbled so, once or twice, to Faux News), never mind actually doing
something serious, like telling them that the Bible belongs in, maybe, a
history course, or literature, not science, math, or even their
distorted and badly warped, revisionist, version of civics.
BTW. Good humor at the latest "Fred Phelp" protest. He had 4 people, the
Comic Con people have like 30, ranging from a guy with a blank sign, to
one saying, "Is this thing on", to a guy in a Bender costume, holding a,
"Kill all humans", sign, and even a shout of, "What do we want? Gay Sex!
When do we want it? Now!". Would love to see some of the, "Making fun of
these people is hurting the cause!", types explain why this isn't a
proper ration to hate mongering.
If everyone was the confused, semi-nice, cherry pick for the cause of
spreading a peace the Bible sort of only has in the later bit, (as long
as you ignore the, "I am going to show up and kill you all anyway, even
if you try to be nice to each other.", bits in the NT...), types, no one
would care, for the most part, including atheist. Well, no more so than
I care that some people hate Star Wars, or Star Trek, badly enough that
both sides would throw things at me, if I showed up at a convention, in
the wrong costume. lol Otherwise, who gives a frack?
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models,
3D Content, and 3D Software at DAZ3D!</A>
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Patrick Elliott <sel### [at] npgcablecom> writes:
> On 7/22/2010 7:58 PM, Neeum Zawan wrote:
>> Their rhetoric isn't helpful. They often ask religious people to defend
>> principles that those religious people don't always believe in, for
>> example. They didn't bother establishing whether the person they're
>> speaking to fits their mental model of a religious person. He merely
>> does, because he's religious.
>>
> Problem with this is, while true, there is a fairly consistent "media"
> trend on what kind of stuff people believe, and that 99% of believers
> may not believe it doesn't help, if what they do believe is just as
> silly.
>
> In any case, you cannot address a position you are not aware of, so you
> address the ones you *are* aware of, which tend to be that presented by
> the loudest, most annoying, incoherent, but visible, people.
Which is my point: They (at least the loud atheists) tend not to know
much about religion.
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Patrick Elliott <sel### [at] npgcablecom> wrote:
> On 7/22/2010 11:02 AM, Warp wrote:
> >> In any case, no, the problem here is that you have to present a
> >> plausible thing to "be" there, if you don't have particles, given that
> >> even breaking up something like an electron gives you... more particles.
> >
> > Matter/energy degenerates under such enormous gravity, forming something
> > which doesn't happen normally elsewhere. It retains certain properties
> > (such as mass) because energy cannot be destroyed nor created, but its
> > physiology may be completely different than normally.
> >
> > It's the same as what happened in the first moments of the Big Bang.
> > There were no particles until later.
> >
> Based on what? Observation?
Pretty much, yes. Observation in the sense that GR has hold up pretty
well in a very large amount of different experiments (including things
like gravitation lensing and orbital measurements of the Moon).
To say that singularities can't exist you would have to demonstrate
somehow that GR stops working when matter density goes high enough (but
is still finite). AFAIK no such observation has been made, so the *simpler*
explanation at this moment is to assume that GR does hold even with
extremely high densities because it doesn't require any additional, yet
unknown, physical models.
One known physical model is simpler than one known plus one unknown
(especially when there's no experimental observation of where the latter
becomes more prominent than the former, so drawing the line between the
two is pretty much impossible).
I have always wondered why it seems that quantum mechanics is somehow
considered "holier" than general relativity. If some physical phenomenon
is predicted which seems to contradict either one or the other, or both,
then it must be GR which breaks, never the "holy" QM, which never breaks
and is always in effect no matter what the circumstances.
--
- Warp
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Darren New <dne### [at] sanrrcom> wrote:
> http://www.dailygalaxy.com/my_weblog/2010/07/did-time-exist-before-the-big-bang.html
Unrelated to the point itself, but I couldn't help but notice how the
article uses the word "theory" with the *colloquial* meaning rather than
the *scientific* one (the more scientific term would have been "hypothesis"
or perhaps even "conjecture").
If even scientific publications confuse the colloquial and scientific
meanings of the word "theory", is it any surprise that laymen do that too
(and hence all the arguments of why the theory of evolution is "only a
theory")?
--
- Warp
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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > According to GR you would need an infinite amount of energy to maintain
> > a shape with non-zero volume. Obviously there isn't an infinite amount of
> > energy inside a black hole.
> Interestingly, according to QM, you need an infinite amount of energy if two
> particles can be zero distance from each other. And that is *exactly* the
> problem.
I suppose the apparent contradiction won't be solved until a unified
theory is discovered.
--
- Warp
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clipka <ano### [at] anonymousorg> wrote:
> However, you may be not so far off the mark regarding black holes:
> AFAIK, those indeed typically have a non-zero (though ever shrinking)
> volume, as in order to form a true singularity you'd need a neatly
> symmetric collapse.
I think you are confusing singularities which are not points (which is
what happens in rotating black holes, AFAIK). Just because the singularity
is not a point (but eg. a ring) doesn't mean it doesn't have zero volume.
A torus can have zero volume if the minor radius is zero (and that, IIRC,
is precisely what the GR equations tell about a rotating black hole).
http://en.wikipedia.org/wiki/Ring_singularity
> Thus, the problem with black holes is probably not the singularity /per
> se/: To me it looks like that's a purely academic issue because there
> bloody likely aren't any such beasts out there in reality. Instead, the
> problem with black holes is that ever-shrinking thing, which doesn't go
> along well with QED's prediction of a lower bound on distances.
I'm not sure what you mean by "ever-shrinking".
--
- Warp
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Patrick Elliott <sel### [at] npgcablecom> wrote:
> Special pleading. That is all I have to say on that. If you don't get
> them, you don't have to make up some *unknown*, and *undefined* thing
> for matter to "be" when its in one.
But assuming the opposite would require an *unknown* and *undefined*
phenomenon of physics which stops matter from collapsing into a singularity.
--
- Warp
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clipka <ano### [at] anonymousorg> wrote:
> I think there's a flaw in here, too: The event horizon itself is subject
> to relativity as well. An observer approaching the black hole in free
> fall will witness the event horizon to "dent in" in front of him, even
> when he himself has already passed the event horizon as witnessed from a
> far-away observer.
I think you have got it completely reversed.
An external observer will never see a falling object crossing the event
horizon. This is because from the external observer's point of view the
time of the falling object slows down as it approaches the event horizon.
The time of the falling object completely stops (from the external
observer's point of view) when it reaches the event horizon (which, in
fact, never happens, as the speed of time approaches zero asymptotically).
So from the external observer's point of view the falling object flattens
into a disc and its time practically stops as it approaches the event
horizon, and it "never" crosses it.
(Of course this is purely under the theoretical assumption that the
external observer could observe the falling object for eternity. This
isn't so in practice because the falling object also red-shifts to black
(again, from the point of view of the external observer) as it approaches
the event horizon, and at some point becomes completely impossible to
observe from the outside.)
The falling object itself experiences no such slowing of time. From its
*own* point of view time continues just normally. It's the time of the rest
of the universe which seems to go haywire.
What the falling object sees as it approaches the event horizon is that
it looks as if the event horizon engulfs the falling object (due to how
light bends near to the event horizon). As the falling object approaches
the event horizon it looks as if the black hole increases in size more
rapidly than the falling speed would dictate. At some altitude (but still
outside of the event horizon) it looks as if the event horizon is a
completely flat plane that takes half of the entire universe (the visible
part of the universe having been "squeezed" to the other half). As it
continues to approach the event horizon, it looks as if the event horizon
bends up, "compressing" the visible universe into an ever-shrinking circle.
Just as the falling object touches the event horizon the circle-shaped
"viewport" of the universe closes and the event horizon seems to completely
surround everything. Then the object passes the event horizon and is now
inside it.
After that it's all weird.
--
- Warp
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Warp <war### [at] tagpovrayorg> wrote:
> I have always wondered why it seems that quantum mechanics is somehow
> considered "holier" than general relativity. If some physical phenomenon
> is predicted which seems to contradict either one or the other, or both,
> then it must be GR which breaks, never the "holy" QM, which never breaks
> and is always in effect no matter what the circumstances.
I came up with a humorous explanation for that.
Quantum physicists don't really like gravity. After all, it's such an
insignificant force at quantum scales that it can be completely left out
of equations and it doesn't change anything. It's way, way weaker than
even the second weakest interaction of the four, and plays no significant
role at all at quantum levels. Thus those puny astrophysicist can keep
their gravity, it doesn't affect us.
But then astrophysicist say that hey, GR actually predicts this phenomenon
where gravity actually becomes a significant force. Not only that, it
actually becomes so significant that it completely overwhelms all the
other forces, including strong interaction. Take that, you quantum physicists.
Your move.
Quantum physicists take this as an invasion of privacy. Those puny
astrophysicists are invading their realm! They could have the *entire
universe* with all the stars and planets and everything, but no, they
can't be content with that, they have to invade our world too with their
annoying theories and equations. But we won't go out without a fight!
Quants cannot lose the battle to gravity!
--
- Warp
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>> According to GR you would need an infinite amount of energy to maintain
>>> a shape with non-zero volume. Obviously there isn't an infinite amount of
>>> energy inside a black hole.
>
>> Interestingly, according to QM, you need an infinite amount of energy if two
>> particles can be zero distance from each other. And that is *exactly* the
>> problem.
>
> I suppose the apparent contradiction won't be solved until a unified
> theory is discovered.
Or until we figure out how to make a black hole we can actually observe the
behavior of, etc. :-) I think QM is more "holy" than GR because it's very
difficult to observe the actual behavior of GR in the extreme. We have only
theories of what goes on inside a black hole's even horizon, whereas QM has
been expermentally validated to a much greater extent with actual
observations, perhaps?
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Neeum Zawan wrote:
> Which is my point: They (at least the loud atheists) tend not to know
> much about religion.
I think the guys who wrote the books (Hitchens, Dawkins, etc) probably
studied it pretty well.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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Darren New <dne### [at] sanrrcom> wrote:
> I think QM is more "holy" than GR because it's very
> difficult to observe the actual behavior of GR in the extreme. We have only
> theories of what goes on inside a black hole's even horizon, whereas QM has
> been expermentally validated to a much greater extent with actual
> observations, perhaps?
But not in those extreme conditions...
--
- Warp
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On Sat, 24 Jul 2010 08:35:54 -0700, Darren New wrote:
> Neeum Zawan wrote:
>> Which is my point: They (at least the loud atheists) tend not to know
>> much about religion.
>
> I think the guys who wrote the books (Hitchens, Dawkins, etc) probably
> studied it pretty well.
Those are the ones I think of when I think of the "loud" atheists.
Jim
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> I think QM is more "holy" than GR because it's very
>> difficult to observe the actual behavior of GR in the extreme. We have only
>> theories of what goes on inside a black hole's even horizon, whereas QM has
>> been expermentally validated to a much greater extent with actual
>> observations, perhaps?
>
> But not in those extreme conditions...
Agreed, certainly. I just think that's why GR is considered less
well-established. We haven't actually built any gravitic engineering
projects. If we actually had black hole power plants like we have QM
transitors, I think we'd probably have much less tendency to favor QM over GR.
(I once had a sci-fi scenario where the power plants were quantum black
holes into which you could feed any sort of matter you wanted and get out
hot hawking radiation to power your tech. I wonder if that might actually
work. :-)
And we have the ability to build the extreme quantum conditions, like cosmic
rays or the LHC. We don't really have the ability to build extreme gravity
conditions yet.
--
Darren New, San Diego CA, USA (PST)
C# - a language whose greatest drawback
is that its best implementation comes
from a company that doesn't hate Microsoft.
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On 7/23/2010 10:27 PM, Warp wrote:
> Patrick Elliott<sel### [at] npgcablecom> wrote:
>> On 7/22/2010 11:02 AM, Warp wrote:
>>>> In any case, no, the problem here is that you have to present a
>>>> plausible thing to "be" there, if you don't have particles, given that
>>>> even breaking up something like an electron gives you... more particles.
>>>
>>> Matter/energy degenerates under such enormous gravity, forming something
>>> which doesn't happen normally elsewhere. It retains certain properties
>>> (such as mass) because energy cannot be destroyed nor created, but its
>>> physiology may be completely different than normally.
>>>
>>> It's the same as what happened in the first moments of the Big Bang.
>>> There were no particles until later.
>>>
>> Based on what? Observation?
>
> Pretty much, yes. Observation in the sense that GR has hold up pretty
> well in a very large amount of different experiments (including things
> like gravitation lensing and orbital measurements of the Moon).
>
Same argument could have, at one time, been made about Newtonian
physics. The first examples of where that didn't work where people
going, "Yeah, but.. what about in this case?"
> To say that singularities can't exist you would have to demonstrate
> somehow that GR stops working when matter density goes high enough (but
> is still finite). AFAIK no such observation has been made, so the *simpler*
> explanation at this moment is to assume that GR does hold even with
> extremely high densities because it doesn't require any additional, yet
> unknown, physical models.
>
Yes it does, it requires matter and energy (which is generally the same
thing) to achieve some undefined state, it requires violations of other
physical rules, like particles holding the same point in space, and a
whole host of other "unexplained" things. Last I checked they didn't
have even the math to describe what things actually look like past the
event horizon, never mind explain what, if anything, the core ends up
being made of, since it obviously, isn't likely particles. There are
problems with the theory, once you get past the point where you can even
theoretically observe, predict, etc., the outcome. Even the explanations
go something like, "And then once you travel past the horizon you get
torn apart and there is nothing but chaos.", which is a fairly lame way
of saying, "We don't have a damn clue, but something has to happen, and
its the only thing we can think of, if GR applies." That's not even a
description, its a wild guess, with no details at all.
> One known physical model is simpler than one known plus one unknown
> (especially when there's no experimental observation of where the latter
> becomes more prominent than the former, so drawing the line between the
> two is pretty much impossible).
>
But, its **not** known. You yourself admit, mind, as a layman, that you
have no clue what "is" in the core of a black hole. I can say, as
someone that reads a lot about it, that the physicists don't have much
better idea. At best, they can point to some sort of QM, which doesn't
really give them any better idea, or string theory, which many are not
sure even describe a real thing, and can't make predictions, of *any*
sort, etc. They don't know. A chart of a black holes structure might as
well be an ancient map, with the center marks, "Here be dragons."
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models,
3D Content, and 3D Software at DAZ3D!</A>
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On 7/24/2010 8:49 AM, Jim Henderson wrote:
> On Sat, 24 Jul 2010 08:35:54 -0700, Darren New wrote:
>
>> Neeum Zawan wrote:
>>> Which is my point: They (at least the loud atheists) tend not to know
>>> much about religion.
>>
>> I think the guys who wrote the books (Hitchens, Dawkins, etc) probably
>> studied it pretty well.
>
> Those are the ones I think of when I think of the "loud" atheists.
>
> Jim
Well, actually Dawkins never even raises his voice.. lol Seriously
though, I do have to wonder if the word being used in this context
really "is" loud, as in the morons that show up on scienceblogs once in
a while, claiming to be atheists, then proceed to show that they have a
badly distorted understanding of religion, science *and* atheism. But,
yeah, despite the odd fact that most of them would, compared to say
Rush, look like a wall flower, the most common, at least from the
religious, word used for them is "strident".
Thing is, you won't find a *lot* of difference in content, though
perhaps a bit more... aggressiveness, between say, PZ Myers, who *might*
be argued, if you ignore the number of posts, or comments to posts,
where he mentions the number of Bibles, other religious texts, etc., he
has read, along with various appologestics people keep sending him, how
he got to be an atheist, and so on-
http://scienceblogs.com/pharyngula/
and something like The Chaplain, who uses the name because they **used
to actually be a priest**-
http://thechapel.wordpress.com/
Both have said, to critics, more or less, "We are not addressing the
nice ones, or some theology that doesn't *exactly* match what we are
using as an example, we are addressing the sort of idiocy we actually
have to deal with, and the damage it causes to society. If you are not
one of these people, then why are you here complaining?"
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models,
3D Content, and 3D Software at DAZ3D!</A>
Post a reply to this message
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