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Dan Bloomquist · Guest

Dan Bloomquist wrote:
[quote]Jerason Banes wrote:
The current evidence in physics, is that the Universe will not
contract and continue to expand forever.

I>m curious about this evidence.
[/quote]
Serendipity. I listen to NPR. Scowl down to:
' Scientists Grapple with 'Dark Energy' Theory '
http://www.npr.org/rundowns/rundown.php?prgDate=31-Dec-2003&prgId=3

Best, Dan.

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Jerason Banes · Guest

[quote]In fact, that>s basic high school physics. As they teach, "There is a
finite amount of energy and matter in the Universe. No matter or
energy may be created or destroyed, but they may be converted." This
seems like a reasonable assumption to make for this discussion. :-)

Yes, but it is not only finite, it is an invariant.
[/quote]
I>m not sure what you mean. Matter can become energy, energy can
become matter, and a few other conversions I won>t dicuss at the
moment. Or are you referring to something else?

[quote]The current evidence in physics, is that the Universe will not
contract and continue to expand forever.

I>m curious about this evidence.

Serendipity. I listen to NPR. Scowl down to:
' Scientists Grapple with 'Dark Energy' Theory '
http://www.npr.org/rundowns/rundown.php?prgDate=31-Dec-2003&prgId=3
[/quote]
Yes, I>ve heard this before. I>m not really sure I buy it. The problem
with the "dark" theories is that they are created for lack of
evidence. i.e. They can>t show a tangible force through either
experimentation or observation, but they can see unexplainable
effects. Therefore, there must be a "dark" something we can>t see.

That>s all well and good, but to then make claims like "it>s going to
run out of steam" is a bit rediculous. The physicists probably needed
to make a splash so they could get more funding.

Personally, I find the theories of inter-universe communication to be
much more appealing. Instead of some "dark" matter or energy producing
gravitational effects, certain forces of our universe trancend our
4ish dimensions of existance. As humans (i.e. products and inhabitants
of our universe alone), we obviously lack the sensory equipment to
look across to another universe. These theories could also explain why
gravity is such a weak force in comparison to the other forces that
propogate through our universe.

As for the expansion/contraction argument, I>m afraid it>s beyond my
resources at the moment to provide a good overview of the different
arguments. However, NASA>s public relations may be of more use to you:

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980114c.html

Overall, the argument against is two-fold. Number one, there isn>t
enough matter to trigger a giant collapse (i.e. the expansive force is
greater than the gravitional forces). The second problem is with the
big bang theory itself. Very simply, we have no models showing how it
could work in the first place. We have a hard enough time trying to
mathimatically define a black hole>s singularity, much less the entire
universe on the head of a pin. We just haven>t been able to work out
the math.

Amusingly enough, a constant cycling universe would violate the second
law of thermodymanics. If the collapse theory were true, then the
entire universe itself is a perpetual motion machine. (oops)

[quote]I am ignorant of super string. But one catch is whether we will ever
make a super-string observation. So, for now, it is philosophical.
[/quote]
Currently, the whole blasted string theory is not provable. How do you
prove a theory that offers nothing other than to find unification in
two highly accurate theories (Quantum Physics and Relativity)? I>m
hopeful that the odd qualities of gravity will perhaps give a foothold
to providing proof, for or against.

[quote]I purposefully left 'time' out when I posted. I have no idea how to four
vector entropy. Just as I left the E=mc^2 stuff alone because space-time
requires tossing a lot of preconceived notions about space-time.

See above on string-theory. If we use the existing laws, there is no
producing matter and energy. The primordial hyper expansion is a theory
to get use beyond the unknown we would have to deal with, without it.
[/quote]
Actually, the space-time curvature is well documented by the theory of
relativity (specifically, the General Theory). Still, we can certainly
leave that out of the discussion without much harm. :-)

[quote]And I>ll put my foot in my mouth on a regular basis, as I>m just a
novice. :) But what the hell, this is as good a place as any to learn.
[/quote]
Nobody ever did anything worthwhile by not making any mistakes. It>s
much more interesting to get a dialog going and help correct one
another. :-)

Thanks,
Jerason

Jerason Banes · Guest

[quote]Mmm, this appeals to me after a few tokes. Are you claiming that 'energy'
is, in effect a 'derivative' in the calculus sense (i.e. 'differential'), of
the expansion of the universe?
[/quote]
You>ll have to forgive me, but I never took calculus. But if I
understand you correctly, you are basically correct. The only thing
I>d point out is that this is true of both matter *and* energy. It>s a
little hard to convey without a good visualization, but I>m thinking
of the universe like a wound up spring that is unwinding. (Not *too*
bad of an analogy from a "big bang"/curvature type of perspective.)
The universal "event" of unwinding happens in both a spacial dimension
(a wound spring goes from thin to thick as it unwinds) and an "applied
force" (i.e. energy) dimension.

In this sense, matter and energy are really attributes of the spring
unwinding and are separate from the event itself. Does that make
sense?

[quote]Thus energy is the universe winding down.

So, according to your hypothesis, as the universe winds down, there will be
increasingly less energy available (since the rate of expansion of the
universe is on the decrease)?
[/quote]
That would be correct.

[quote]Mmm, but entropy has been typically associated with cycles of universal (in
the sense of 'the universe') expansion and contraction.
[/quote]
Entropy says that the Universe winds down, period. In order to support
a cyclic universe, scientists have to make the statement that "entropy
must be reset". So far that claim is nothing more than a hypothesis
based on a difficulty in a theory.

[quote]Work is attempts to unbalance that energy in order to make something
useful happen.

No, work is simply local exergy exchange.
[/quote]
Umm... the only definition of exergy I have is that it refers to the
continual reduction in the quality of energy in the universe. i.e.
Energy once used is less useful than it was before. Here>s a page on
it:

http://www.holon.se/folke/kurs/Distans/Ekofys/fysbas/exergy/exergybasics.shtml

Thanks,
Jerason

Fred B. McGalliard · Guest

"Don Lancaster" <don@tinaja.com> wrote in message
news:3FEA19D6.ABD27AC8@tinaja.com...
[quote]"Ivar S. Ertesvåg" wrote:

Energy is the potential for doing work.

A statement doesn>t become more true just by repeating it.

But the FACT that it is in virtually EVERY physics test DOES make it a
lot MORE true.
[/quote]
Don understates the strength of his case. (I think he meant text not
"test".) "virtually" and "a lot MORE" make it sound like a simple consensus
rather than the beginning of a very carefully crafted physics. Think of it
more like the foundation stone of a vast structure, more like an inverted
pyramid resting on this heart stone.

Fred B. McGalliard · Guest

"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FEA1B85.9038933B@mtf.ntnu.no...
[quote]The 2nd law was formulated in the early 1850s: Some energy can not
be used for doing work. Which tests contradict this?
cf. my questions to your former posting.
[/quote]
Not precisely true. Permitted expansion to a vacuum and cooling to 0K, all
energy is extractable. The essential one wayedness of conversions from
mechanical energy to heat do not change the idea. You are just confusing
things here because of a lack of familiarity.

Fred B. McGalliard · Guest

"Roland Paterson-Jones" <roland@rolandpj.com> wrote in message
news:bsie9u$ing$1@ctb-nnrp2.saix.net...
[quote]...
You>re all wrong. Energy and work are interchangeable. Much of modern
physics depends upon energy balance.
[/quote]
But you should understand that heat energy is not available work within the
problem boundary (that is the hot and cold reservoirs we are using to make
our heat engine work). Remember the adjournment, a solution should be as
simple as possible but no simpler.

Ivar S. Ertesvåg · Guest

"Fred B. McGalliard" wrote:
[quote]
"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FEA1B85.9038933B@mtf.ntnu.no...
The 2nd law was formulated in the early 1850s: Some energy can not
be used for doing work. Which tests contradict this?
cf. my questions to your former posting.

Not precisely true. Permitted expansion to a vacuum and cooling to 0K, all
energy is extractable. The essential one wayedness of conversions from
mechanical energy to heat do not change the idea. You are just confusing
things here because of a lack of familiarity.
[/quote]
How do you expand something to vacuum (=nothing)?
For producing work (which was the question here): How do you drain the
vacuum? (cf. the condenser in a Rankine cycle).

Duke McMullan N5GAX · Guest

"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FF73731.218B2A26@mtf.ntnu.no...
[quote]

"Fred B. McGalliard" wrote:

"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FEA1B85.9038933B@mtf.ntnu.no...
The 2nd law was formulated in the early 1850s: Some energy can not
be used for doing work. Which tests contradict this?
cf. my questions to your former posting.

Not precisely true. Permitted expansion to a vacuum and cooling to 0K,
all
energy is extractable. The essential one wayedness of conversions from
mechanical energy to heat do not change the idea. You are just
confusing
things here because of a lack of familiarity.

How do you expand something to vacuum (=nothing)?
For producing work (which was the question here): How do you drain the
vacuum? (cf. the condenser in a Rankine cycle).
[/quote]

Fred>s speaking of "in principle" thermodynamics. Think of it in terms of
limits. If your working fluid expands into an arbitrarily large volume,
cooling arbitrarily close to absolute zero, you can extract an arbitrarily
large fraction (approaching 1.0) of the available energy.

But it costs too much and takes too long to do anything like it in
practice.

Hence, "in principle" only.

d
--
This saying would be seven words long if it were six words shorter.
Duke McMullan n5gax nss13429rl(fe) (505)255-4642 mtmduke@qwest.net

Ivar S. Ertesvåg · Guest

Duke McMullan N5GAX wrote:
[quote]
"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FF73731.218B2A26@mtf.ntnu.no...

"Fred B. McGalliard" wrote:

"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FEA1B85.9038933B@mtf.ntnu.no...
The 2nd law was formulated in the early 1850s: Some energy can not
be used for doing work. Which tests contradict this?
cf. my questions to your former posting.

Not precisely true. Permitted expansion to a vacuum and cooling to 0K,
all
energy is extractable. The essential one wayedness of conversions from
mechanical energy to heat do not change the idea. You are just
confusing
things here because of a lack of familiarity.

How do you expand something to vacuum (=nothing)?
For producing work (which was the question here): How do you drain the
vacuum? (cf. the condenser in a Rankine cycle).

Fred>s speaking of "in principle" thermodynamics. Think of it in terms of
limits. If your working fluid expands into an arbitrarily large volume,
cooling arbitrarily close to absolute zero, you can extract an arbitrarily
large fraction (approaching 1.0) of the available energy.

But it costs too much and takes too long to do anything like it in
practice.

Hence, "in principle" only.
[/quote]
If this extraction cost more work (exergy) than the work that can be
generated from the extracted energy, this shows that energy is not
equivalent to work (also "in principle").
Cooling something to 0K costs an infinite amount of work, regardless
of how close to 0K you start.

Roland Paterson-Jones · Guest

"Fred B. McGalliard" <frederick.b.mcgalliard@boeing.com> wrote in message
news:Hqvsqq.zC@news.boeing.com...
[quote]
"Roland Paterson-Jones" <roland@rolandpj.com> wrote in message
news:bsie9u$ing$1@ctb-nnrp2.saix.net...
...
You>re all wrong. Energy and work are interchangeable. Much of modern
physics depends upon energy balance.

But you should understand that heat energy is not available work within
the
problem boundary (that is the hot and cold reservoirs we are using to make
our heat engine work). Remember the adjournment, a solution should be as
simple as possible but no simpler.
[/quote]
Whence my definition of 'energy' as the potential to do (mechanical) work in
outer space.

Roland

--
Roland and Lisa Paterson-Jones
Forest Lodge, Stirrup Lane, Hout Bay
http://www.rolandpj.com/forest-lodge
mobile: +27 72 386 8045
e-mail: forest-lodge@rolandpj.com

[quote]
[/quote]

Fred B. McGalliard · Guest

"Ivar S. Ertesvåg" <ivar.s.ertesvag@mtf.ntnu.no> wrote in message
news:3FF7F8DE.6E3E5DC3@mtf.ntnu.no...
....
[quote]If this extraction cost more work (exergy) than the work that can be
generated from the extracted energy, this shows that energy is not
equivalent to work (also "in principle").
Cooling something to 0K costs an infinite amount of work, regardless
of how close to 0K you start.
[/quote]
Expand into free space, that>s a pretty good vacuum. Dump to the 3K
background. That>s pretty cold. Sounds easy in principal, you just have to
push your experiment into space.


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