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Patrick Elliott <sel### [at] npgcable com> wrote:
> In fact, this may be more correct than one might think. There is at
> least one alternative theory about "black holes", which Hawkings is the
> one suggesting, which suggests that the concept of singularity is itself
> flawed.
I assume that the opposition some astrophysicist have against singularities
stems from the fact that the equations of relativity fail there (in simple
terms, you get a division by zero, which thus tells you nothing). In other
words, the theory of relativity predicts the existence of a phenomenon which
it cannot formulate. Something else would then be needed to formulate the
physics of a singularity.
That something might not even exist. Some physicists hence conjecture
that perhaps it's the singularities which do not exist, even though the
relativistic equations predict them. Maybe the known laws of physics change
somehow when space bends enough.
> Basically, you can't form one, you can only get increasingly
> larger, hotter, objects, which, due to their gravitation, merely "look
> like" a singularity.
There would have to be an unknown phenomenon of physics which would stop
matter and energy from collapsing into a singularity. No such phenomenon
has been observed nor probably even plausibly conjectured.
> Worst thing about this problem is that, even the fact that it took us
> until now to see that far means that things that are beyond a certain
> distance are not lost in the wash of the speed barrier, which would have
> been visible a few thousand years ago, and more lost to it from tens of
> thousands, and more from millions, etc. We can never, from our position,
> short of finding a way past the limit of the speed of light, ever *see*
> any of those things, and given long enough, assuming the sun somehow
> survived that long, or our species did, by moving around elsewhere,
> those descendants would look up and go, "Obviously all that stuff about
> constellations they once wrote is nonsense, nothing is visible past this
> single galaxy."
Constellations have nothing to do with other galaxies.
And my guess is that the Sun will explode way before the universe has
expanded so much that we can't see any other galaxies anymore.
--
- Warp
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Warp wrote:
> cosmogony. There are many conjectures (one example being that the universe
> is actually cyclic, expanding and then collapsing back to a singularity,
Yep. Another is the whole "two branes slapping together" kind of thing.
Presumedly if the branes are doing something, there's some equivalent of
time and space and causality in which to do them. Maybe not exactly like the
sort of run-down left over time we get in these parts, but still...
--
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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andrel wrote:
> Sigh, again: Big Bang theory says that the universe started with the big
> Bang, so time did. End of story.
From Wikipedia:
"Without any evidence associated with the earliest instant of the expansion,
the Big Bang theory cannot and does not provide any explanation for such an
initial condition; rather, it describes and explains the general evolution
of the Universe since that instant."
Do you have some cite that would contradict this? I haven't heard of any
such thing.
--
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 5:33 AM, Warp wrote:
> Patrick Elliott<sel### [at] npgcablecom> wrote:
>> In fact, this may be more correct than one might think. There is at
>> least one alternative theory about "black holes", which Hawkings is the
>> one suggesting, which suggests that the concept of singularity is itself
>> flawed.
>
> I assume that the opposition some astrophysicist have against singularities
> stems from the fact that the equations of relativity fail there (in simple
> terms, you get a division by zero, which thus tells you nothing). In other
> words, the theory of relativity predicts the existence of a phenomenon which
> it cannot formulate. Something else would then be needed to formulate the
> physics of a singularity.
>
> That something might not even exist. Some physicists hence conjecture
> that perhaps it's the singularities which do not exist, even though the
> relativistic equations predict them. Maybe the known laws of physics change
> somehow when space bends enough.
>
>> Basically, you can't form one, you can only get increasingly
>> larger, hotter, objects, which, due to their gravitation, merely "look
>> like" a singularity.
>
> There would have to be an unknown phenomenon of physics which would stop
> matter and energy from collapsing into a singularity. No such phenomenon
> has been observed nor probably even plausibly conjectured.
>
It might be noted that singularities where hypothesized "before" we knew
some things in QM that we do now, and other things as well. Not sure
what the specifics are, but I would seem to think that the guy that
concluded that black holes *would* give off some radiation, and was
proven right, also saying that singularities may be wrong, has at least
*some* odds of having a reason to say so. lol
But, seems to me to be reasonable anyway. The closest you can get in a
Bouse Einstein Condensate, by cooling things down, and that is about as
close as particles can get to each other, since at that point they "stop
moving", there being no space left for them to do so, presumably. How do
you get denser than that, even if you reduce the particles to
sub-particles, like quarks and muons? In some ways, singularity is a bit
like the Zeno's Paradox concept. The math may say that it is possible,
but no one knows *if* that is possible, they just assume so, because the
math says so. Well. Zeno has a similar problem, and if taken to its
logical conclusion, Zeno would be right. Since he isn't, we take the
opposite view from singularity, and assume there *must be* some finite
"size" for an event, such that you can stack events together, thereby
actually reaching a destination. In point of fact, one of the recent
experiments has shown that time, at least as far as QM is concerned,
*does* have a finite "slice" size, and seemingly instant events actually
take that tiny, minuscule, time to happen, such that you can interrupt
the result, and get a different one, even when the state "should have"
become fixed, and thus irrecoverable.
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. Observation says so,
even though the math says Zeno should have been right. That the math for
singularity is the same. Its "assumed" that singularities happen,
because the math says they are the logical conclusion. 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.
We will have to see what Hawkings eventually publishes on the subject
though, and he has only put out some preliminary things about the
subject, so far.
--
void main () {
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 7/21/2010 5:33 AM, Warp wrote:
>
> Constellations have nothing to do with other galaxies.
>
> And my guess is that the Sun will explode way before the universe has
> expanded so much that we can't see any other galaxies anymore.
>
Probably true, but irrelevant, the point isn't if "we" will be around to
see it, but that if anyone/thing *is* they won't see anything when they
look.
--
void main () {
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 7/20/2010 8:07 PM, Kevin Wampler wrote:
> Patrick Elliott wrote:
>> On 7/20/2010 12:47 PM, Kevin Wampler wrote:
>>> By the way, these questions are getting beyond the point where I feel
>>> comfortable speculating how an actual young-earth creationist would
>>> respond, so if you're actually interested in knowing the answers you'll
>>> probably have to actually find a young-earth creationist who is also
>>> scientifically minded and ask them.
>>
>> Actually, its real easy to work out how they might answer. Its called
>> Poe. Nothing you can possible think of would *ever* prove to be
>> crazier, less rational, or inconsistent with reality, than what some
>> creationist, someplace, somewhere, just posted to a blog (or
>> Conservapedia).
>>
>
> That's why I used the phrase "a young-earth creationist who is also
> scientifically minded", indicating that he should try to find a someone
> who has thought and read a fair bit about how to best fit science into
> that sort of world view. Such people do actually exist, and I imagine
> will have a much less varied set of responses than the set of all
> young-earth creationists.
Don't know.. Maybe, but as near as I can see, their responses tend to
contain *way* more cognitive dissonance, and severe confusion over what
their actual position on things are. I.e., X is true for A, because that
doesn't contradict my position, but its wrong for B, C, D, and J->Q,
because it does, even though there is no logical reason why it shouldn't
apply there as well.
--
void main () {
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 20-7-2010 23:41, Darren New wrote:
> andrel wrote:
>> I am talking about both time and space. You know, that 4 dimensional
>> thing.
>
> I think the point that Warp is making (and I agree with) is that space
> and time is only a four-dimensional thing in our current universe with
> our current physical laws. If those laws didn't hold before the big
> bang, there's no reason to believe there couldn't be space without time
> or time without space or that the speed of light has anything to do with
> anything in whatever universe was around before the big bang.
yikes, my mind boggles again as it does everytime when someone uses the
phrase "before the big bang". I know it is counter intuitive* for many
people that time does not run infinitely backwards**, (and if I didn't
know it, this thread would have been proof) but that phrase does not
make sense. Really, it doesn't. I can not remember if I had the same
problem when I first encountered it, that is quite possible, in which
case it is a classical example of "trivial" ;)
>> below 0K and time before the Big Bang are both completely nonsensical
>> and for exactly the same reason.
>
> So you know about the physics of the universe before the big bang,
> enough to know that there couldn't be time of any sort before the big
> bang? How about light? How about gravity? Are those incompatible with
> "before the big bang"?
There is no before, because there was neither space nor time for
anything to happen.
>> Sigh, again: Big Bang theory says that the universe started with the
>> big Bang, so time did. End of story.
>
> The theory says *this* universe started with the big bang. But that
> doesn't mean there was neither time nor space before the big bang,
> right?
no it does.
> Or has science actually changed "we can't tell what happened
> before the big bang" to "we have actual scientific evidence that there
> was no existence of anything before the big bang"?
see above. I am sorry, but I can not explain it any other way. Perhaps
somebody else may help.
*) in modern physics things being counter intuitive seems to be quite
common.
**) my own model to cope with this concept is assuming that time is not
linear but slows down if you come closer to the origin. That way there
would be an infinite time going backwards, yet that would asymptotically
approach t=0 in the now fashionable linear time. But that is just for me
to cope with it, not an accepted theory. BTW There is also a problem
that you don't have anything to measure time with if you get too close
to the BB. If that is only a practical problem or something more
fundamental I don't know either.
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andrel wrote:
> yikes, my mind boggles again as it does everytime when someone uses the
> phrase "before the big bang".
I know that *our* time started with the big bang. But you're giving no
indication that there wasn't something out there for the "big bang" to have
come from.
> There is no before, because there was neither space nor time for
> anything to happen.
How do you know, if your physics doesn't cover or explain the event?
*That* is what we're asking. You have a singularity. You're assuming
there's nothing on the other side of the singularity. Why is that?
In other words, why are you so convinced that
http://en.wikipedia.org/wiki/Big_Bounce
is actually necessarily incorrect?
I'm sure this guy publishing letters in Nature's Physics journal is simply
confused by the counter-intuitive nature of physics, right?
http://www.nature.com/nphys/journal/v3/n8/abs/nphys654.html
I'm quite comfortable with the concept that time started with the big bang.
I just don't know that there's actually *evidence* for that beyond the fact
that the math we use *breaks down* at the big bang. In order for you to
definitely assert that there was no time or space before then, you actually
have to explain how you know, instead of just handwaving that because you're
right, I'm mistaken to ask how you know you're right.
--
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:
> 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.
> 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
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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!"
Jim
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