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Warp <war### [at] tag povrayorg> wrote:
> nemesis <nam### [at] gmailcom> wrote:
> > Try sci.astro and have old wolves devour your idea.
>
> I'm reading some of the latest posts there. Over half of the posts are
> spam (*sigh*, I still remember the time in the mid-90's when there was
> virtually *no* spam in usenet, as incredible as that might sound today)
> and most of the rest seems to consist of pseudoscientists writing miles-long
> essays on their newest fads and denigrating established theories and known
> scientists.
>
> I'm guessing that if I posted there, nobody would actually answer my
> question and instead I would get a few totally useless "the Big Bang
> theory is BS" replies.
yes, lots of loonies (and spam) there. Still, those are rapidly torn apart by
actual astrophysicists or wannabes with quite some knowledge. Some interesting
discussions follow from time to time...
sci.astro is much better than alt.astronomy BTW. ;)
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Warp wrote:
> "In systems that are gravitationally bound, such as galaxies or our
> planetary system, the expansion of space is a much weaker effect than
> the attractive force of gravity."
Yeah, I was interpreting that kind of statement as "gravity holds things
together in spite of the expansion of space trying to pull them apart." On
the other hand, it could be that the "dark energy" (i.e. vacuum energy) or
expansion of space or whatever is actually suppressed (in some sense) by the
presence of normal energy or the presence of curved space. I don't know at
this point any more.
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > "In systems that are gravitationally bound, such as galaxies or our
> > planetary system, the expansion of space is a much weaker effect than
> > the attractive force of gravity."
> Yeah, I was interpreting that kind of statement as "gravity holds things
> together in spite of the expansion of space trying to pull them apart." On
> the other hand, it could be that the "dark energy" (i.e. vacuum energy) or
> expansion of space or whatever is actually suppressed (in some sense) by the
> presence of normal energy or the presence of curved space. I don't know at
> this point any more.
Has it even been hypothesized *why* the expansion of the universe
happens? Or is it just another one of those "it just happens, we don't
really know why" things?
--
- Warp
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Warp wrote:
> Has it even been hypothesized *why* the expansion of the universe
> happens?
Dark Energy! ;-)
Seriously, I think they think it has something to do with zero-point energy,
i.e., the fact that virtual particles will spontaneously come into existence
and then annihilate each other again. I can't really say I understand it
beyond "it's something about quantum" (as Terry Pratchett would say)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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Darren New <dne### [at] sanrrcom> wrote:
> Seriously, I think they think it has something to do with zero-point energy,
> i.e., the fact that virtual particles will spontaneously come into existence
> and then annihilate each other again. I can't really say I understand it
> beyond "it's something about quantum" (as Terry Pratchett would say)
Even if that explains the current expansions, would it explain the
initial rapid inflation?
Seemingly not, as there appears to be a hypothesis for a different particle
that caused the cosmic inflation: http://en.wikipedia.org/wiki/Inflaton
I don't understand, however, how a particle would explain inflation
(or just the "normal" expansion of the universe), because such a particle
should be bound to the maximum speed limit of c, as any other particle.
How can it cause the universe to expand faster than c?
--
- Warp
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Seriously, I think they think it has something to do with zero-point energy,
>> i.e., the fact that virtual particles will spontaneously come into existence
>> and then annihilate each other again. I can't really say I understand it
>> beyond "it's something about quantum" (as Terry Pratchett would say)
>
> Even if that explains the current expansions, would it explain the
> initial rapid inflation?
I don't think so, no. Certainly not if the whole quantum mess didn't even
start until after inflation. (I hadn't realized that "inflation" actually
happened that early and quickly until this conversation.)
> Seemingly not, as there appears to be a hypothesis for a different particle
> that caused the cosmic inflation: http://en.wikipedia.org/wiki/Inflaton
Damn. Inflation ended when the universe was only one meter across? Yow.
> How can it cause the universe to expand faster than c?
Only if the actual energy turned into space, or something? I have nothing
buy BS guesses for that. :-)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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Darren New <dne### [at] sanrrcom> wrote:
> > Seemingly not, as there appears to be a hypothesis for a different particle
> > that caused the cosmic inflation: http://en.wikipedia.org/wiki/Inflaton
> Damn. Inflation ended when the universe was only one meter across? Yow.
I'm not sure it says that. It says how long it took for the universe
to become 1 meter accross, not that the inflation ended there. (Also this
seems to completely lack a reference, so it could be some editor's BS.)
--
- Warp
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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>>> Seemingly not, as there appears to be a hypothesis for a different particle
>>> that caused the cosmic inflation: http://en.wikipedia.org/wiki/Inflaton
>
>> Damn. Inflation ended when the universe was only one meter across? Yow.
>
> I'm not sure it says that. It says how long it took for the universe
> to become 1 meter accross, not that the inflation ended there. (Also this
> seems to completely lack a reference, so it could be some editor's BS.)
>
Good point. http://en.wikipedia.org/wiki/Early_universe#Inflationary_epoch
implies it ended somewhere around 10^-32
http://en.wikipedia.org/wiki/Inflationary_epoch
And of course, they say "then the universe filled up with energy that came
from potential energy." I don't know how you store potential energy in a
"field", so it's either way over my head, or BS. :-)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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http://io9.com/5694701/does-cosmic-background-radiation-reveal-the-universe-before-the-big-bang
Actually, I think it's clear nobody really has a clue. :-)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
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Am 21.11.2010 04:12, schrieb Darren New:
>
>
http://io9.com/5694701/does-cosmic-background-radiation-reveal-the-universe-before-the-big-bang
>
>
> Actually, I think it's clear nobody really has a clue. :-)
And AC said, "LET THERE BE LIGHT!"
And there was light--
Isaac Asimov, "The Last Question"
(http://www.multivax.com/last_question.html)
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