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"In Search of the Big Bang" (brief review)



 
 
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  #61  
Old June 1st 05, 11:49 AM
abrasive
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EL wrote:
[Too Many Kooks Spoil the Brothel wrote]:
Unky Alby inscribeth:
Too Many Kooks Spoil the Brothel wrote:

Aren't we all!

Look in any direction - all 4(pi) steradians. Direct exactly in-line
at the end of your gaze is the Big Bang. Idiot.


Methinks you missed the subtlety, Groucho.

[EL]
AL is a genius, of course, because when the probability is infinite
then anywhere should do.
The problem is in the cause that for no reason decided to be once and
for all!
As if a God is making an experiment in her own pace.
Let there be ****.
Let **** burn and emit light.
Or perhaps:
"Let there be all, but where is there if there is nowhere for all to
be."
And God said: "What the heck, let a bang decide for itself to be
anywhere".
And so it was, and God found that the Bang was Big, and God found that
Big is good. :-)
And God said, "Let us make mankind as small as us to see that the bang
was big."
Then God said, "Lat mankind fornicate and produce physicists with very
tiny brains to discover our Bang that was Big and argue not the
ridiculousness of idea."
And so it was, as God said, and earth was filled with clowns.
Then God said, "Let there be an internet and Usenet news-groups to
debate and make fun of us so that we are never bored again." :-)

Hahahahaha

EheheL


no no, that is much simpler, the people didnt yet realised thet the
probability is not mathematics

  #62  
Old June 1st 05, 11:53 AM
Too Many Kooks Spoil the Brothel
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EL wrote:
[Too Many Kooks Spoil the Brothel wrote]:
Unky Alby inscribeth:
Too Many Kooks Spoil the Brothel wrote:

Aren't we all!

Look in any direction - all 4(pi) steradians. Direct exactly in-line
at the end of your gaze is the Big Bang. Idiot.


Methinks you missed the subtlety, Groucho.

[EL]
AL is a genius, of course, because when the probability is infinite
then anywhere should do.
The problem is in the cause that for no reason decided to be once and
for all!
As if a God is making an experiment in her own pace.
Let there be ****.
Let **** burn and emit light.
Or perhaps:
"Let there be all, but where is there if there is nowhere for all to
be."
And God said: "What the heck, let a bang decide for itself to be
anywhere".
And so it was, and God found that the Bang was Big, and God found that
Big is good. :-)
And God said, "Let us make mankind as small as us to see that the bang
was big."
Then God said, "Lat mankind fornicate and produce physicists with very
tiny brains to discover our Bang that was Big and argue not the
ridiculousness of idea."
And so it was, as God said, and earth was filled with clowns.
Then God said, "Let there be an internet and Usenet news-groups to
debate and make fun of us so that we are never bored again." :-)

Hahahahaha

EheheL



Dear Sir/Madam (eek!),

I shall build a monument to your bardic genius (on Planet Gremlin, of
course), and it shall be inscribed with your poetry.

  #63  
Old June 1st 05, 01:13 PM
Dishman
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N:dlzc D:aol T:com (dlzc) wrote:
Dear George Dishman:


Hello David,

"George Dishman" wrote in message
...

Greg, you and David both seem to be discussing
the discrepancy in the change of radius of the
orbit as a possible direct consequence of the
Hubble flow. I don't quite follow that. If there
was a slight radial expansion, surely it wouldn't
be progressive.


I don't understand the choice of word "progressive" here George?


Simply that the radius increases year by year
rather than being at a fixed value which is
larger than anticipated.

Imagine the Moon is moving perpendicularly to the
Earth-Moon line but at a speed which is marginally
too slow to maintain the orbit. In a short time,
it would move closer to the Earth. If you then add
expansion, that could just balance the inwards
motion thus what we would see would be a stable
circular orbit but at a speed fractionally slower
than would be expected for the radius.


I would think that this would obtain an elliptical orbit over the
two+ billions of years that we have records for the orbit of the
Moon. The "necessary deficit" would be variable over the entire
range of orbits...


Yes, I originally started by considering a
circular orbit to simplify the explanation but
lost that part in the edting somehwere :-(
Sorry for the confusion.

In reality, the discrepancy would probably be less
than the accuracy of the measurement of GM for the
Earth but in principle, I don't see why you both
think there would be a resulting secular increase
of the radius.


I don't think he was trying to defend this. I think he was
simply trying ot have a modifier added to my claim that
"expansion was observed"... something like "perhaps", or "it
would appear that". (Sorry if I've caused you grief, Greg.)


I think he was pointing out that there was
a difference between observing a discrepancy
and showing it matches the perturbation
predicted by some hypothesis. In fact that
could also be the same as my question.

I had a look at the paper David mentioned and it is
only cited by one other:

http://lanl.arxiv.org/abs/gr-qc/0306091

Although much of it is beyond me, equation (63)
seems to be relevant to the discussion.

Hoping you can clue me in ...


I wondered if the local parameters might not be a function of our
position wrt the center of the Milky Way, and the "dynamo" that
powers it. I see the same issues with my fantasy, as I do with
his third paragraph after this formula, starting "We want to
suggest that each scale of this hierarchy of structures could
have its own Cosmology, so to speak,". Namely, "how do it know
how to behave"? The parameters very much "define the metric", so
how can the metric be relied upon to convey the "local" values of
these parameters?

I was simply believing that H0 was the same everywhere, as the
least "ad hoc" solution.


I am not disputing that it is reasonable to
assume that the local value of H_0 would be
similar to, though not necessarily exactly
the same as, the large scale average. What
I am querying is the assumption that it
would produce a secular increase of the
orbital radius.

Taking eqn (63) as a possible alternative,
I might expect that if, in the absence of
expansion, the mean radius was R, then the
inclusion of expansion would increase the
mean radius to R + H_0 * R^2 / c but this
would be constant (other than the known
tidal influence of course).

Does that make the question clearer?

best regards
George

  #64  
Old June 1st 05, 03:39 PM
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Greg Hennessy wrote:
In article D5Rme.1537$Pp.1442@fed1read01,
N:dlzc D:aol T:com \(dlzc\) N: dlzc1 D:cox wrote:
Good point. LLR is usually in the range of +/- 0.10 cm/year or
less. And is *compensated* to be a center-to-center measurement,
not surface to surface as some have surmised.


I acutally had in mind the errors in the predicted value, not the
measured value, which I'm pretty sure will be much larger.

Pardon me, but wasn't the *difference* between tidally driven
increase (evident in the period) and a *possible* "hubble flow"
increase distinguishing enough?


No, since there is no way to distinguish between them.

If you want to claim that the paper showed a *possible* hubble flow,
I'll not object much, but to claim it *observed* it is a while
different matter.

What other candidates do we have to choose from, that
are not captured in the Moon's increasing period?


The burden does not lie upon me to come up with other possible
explanations, if the author of the paper wants to claim he observed an
effect it is up to him to list all the other possible reasons, and the
reasons for excluding them.


Go out on a clear night- observe the incoming matter
(asteroids/meteors).
The earth and moon are both gaining mass; the period of course will
alter correspondingly.
No BB is required to explain any possible change in the orbits in the
solar system............end of story

Jim G
c'=c+v

  #65  
Old June 1st 05, 07:48 PM
T Wake
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"Nick" wrote in message
oups.com...


T Wake wrote:
"Nick" wrote in message
oups.com...
Wrong Twake. Einstein says energy curves space.
That is his GR.

Show me where I am wrong


It says gravity curves spacetime.

Now its your turn Nick.


So. Energy curves space-time.
Is that all you can say moron?
Time curves too.
Curved time is slower time.
Einstein says the overall curvature of energy is half
space and the other half time.
Show me where I am wrong.


Energy is not "gravity."



  #66  
Old June 1st 05, 09:41 PM
Nick
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But gravity is a consequence of it.

  #67  
Old June 1st 05, 11:49 PM
George Dishman
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"EL" wrote in message
oups.com...
[George Dishman wrote]
What is inside then is "The Past"
which of course is always increasing.
[EL]
That is a very wonderful idea, George.


Not mine, De Sitter's perhaps?

[EL]
It was and it still is the fashion.
Now we have a complete century full of sophistry pretending to be a
fantabulous vision.
While the past was said to be inside, the future outside and now is at
the door, your height is yesterday, your volume is now and your shoe
size is tomorrow. :-)
The 4D spacetime misconception has devastated a whole century and
turned us into celebrity clowns rather science professors. Since when
was "time" perpendicular to any preferred tangent to a surface!
I know the business very well, concerning the progression of motion
where each spatial coordinate checked corresponds to an event
associated with a temporal coordination within any arbitrated system,
and de Sitter, respectfully, explained that the surface of an expanding
sphere marks a temporal incident, thus the radius may represent a time
line as well. But what you are missing is that motion is not a time
concept exclusively and we should include the spatial concept unless we
were begging for laughter and applause from our circus audience.

Easy, if the analogy models time as the radial
distance from the centre,

[EL]
Indeed, and I apologise for my mockery, which I could not resist.


Understood, I'll treat the above comments as
more of the same.

Yet that model would be nonsense if that time was not associated with
motion (expansion).
Here expansion is also nonsense when it is meant to be the expansion of
time alone.


It isn't, it represents expansion of space (the
surface of the balloon) as a function of cosmic
age (the radius).

a surface of given cosmic age is one of given radius,
hence it is a sphere.
Your cube may seem a witty riposte but it is irrelevant.

[EL]
I am not witty at all, and it was accidental.
I hate taking credit when I do not deserve one.
What I am saying is that the analogy is "lobotomised".


Everyone knows that, it is of very limited use.

I accept integrating space and time into spacetime but I strongly
refuse replacing a spatial distance by the time representation LESS the
concept of associated motion that drags the identity of space along.
When motion takes the relative value of a zero (arbitrated
significance), time keeps increasing but is nonsensical without the
coordinates of the identity that marked the stationary state of motion.
Therefore, THAT radius does not ONLY represent time but ALSO represents
space, which the analogy severs without any logical justification.
How can we calculate the curvature of the surface of the expanding
universe? ;-)
*Warning: This is a very tricky question, so be careful when you answer
it.*
I am trying to be a "nice" person for a change. :-)


Sorry to dissapoint but my maths isn't good
enough to answer properly, but the analogy
isn't a model so your question doesn't
relate to the balloon at all.

I never saw any proposed unified dimension for space and time.


You should get out more ;-)

[EL]
Could you recommend the entertainment facility in which I could find
what I seek? :-)


The only logical concept that can have a geometrical
centre anywhere is infinity.


Any point on the surface of a sphere can also
be considered equally central with any other
point yet it is finite ;-)

[EL]
The surface Area is finite, and the curvature at any event is finite,
and the radius must consequently be spatially finite.


The radius is perpendicular to all the spatial
axes so is not spatial at all.

Therefore we are
inquiring about the centre from which that radius is being measured and
not a centre on the surface because that would be clownish.


Of course.

And it is
clownish sophistry to befuddle the laymen only.
I insist to inquire about the centre from which the "time-radius" is
being measured and not a point on the surface at all.


The beginning of time of course.

Since the centre is in the past, you have to run
time back and see which point in space was at the
centre at t=0. Since cosmological age is represented
by the radius of the balloon, your question becomes
which point on the surface is at the centre when the
radius is zero. The answer of course is all of them
or "everywhere".
[EL]
True but silly when we seek the centre of today's universe.


You might be, I'm not. Why would we be so silly
as to look for something that doesn't exist?

[EL]
I did not say that you were silly; seeking a centre of infinity is
silly.
It is silly because we already know that there is no preferred
coordinate that can be the centre of infinity.


That's right, that's why nobody is looking for it.
Did you read Wright's pages?

However, I am disputing the model that projects a finite and unbounded
universe, which never admitted that the universe was infinite, which I
am certain to be infinite, hence the silliness.


Silliness is being certain without evidence. Anyway,
the Big Bang model also says it is infinite so what
is your point?

Now, with a finite and unbounded universe, which expands like a
balloon's contiguous surface, one expects consistency of the model, and
expects a Gaussian curvature of such a finite surface of that finite
universe.
The curvature demands a spatial radius and not a temporal one.


Why?

If that
surface of the universe was physical rather than simple clownish
sophistry, then constructing a normal line to the surface at multiple
points of tangency, the lines should intersect at that hypothetical
centre.


No, they converge at the beginning of time since
all are time-like lines.

However, I already know that the analogy and the whole model is
nothing more than clownish sophistry and I am not expecting any
conclusive answers to my sarcastic inquiery.


Good.

We cannot test an assumption's validity if you follow the consequences
of the assumption assuming its validity.
My question is that assuming that the Big Bang model was correct then
that past starting point is logically evolving as a reference to
whatever is accelerating away from that point ALL THE TIME and not just
at the instant of the bang. This implies that if there is any proposed
assumption that the universe is STILL expanding, then it must be still
expanding away from that still existing centre, WHICH IS ANY OBSERVER
ON EARTH.
Does that make sense!


Not if you are talking of the Big Bang model that
everyone else discusses. It is homogenous and
isotropic so has no cent

[EL]
I dispute the lack of consistency, when the universe is modelled as
finite as I explained above.


The inconsistency is because you said the time axis
has to be spatial. What do you expect.

The logical consequences of a finite surface is a finite volume and a
finite radius and a finite centre for the topology of expansion
mediating the volume and not the surface area.
Did Einstein admit that the universe, in his model, had a finite
surface and an infinite volume!
He did NOT.


That's right. The balloon analogy only applies if the
mean density is above critical and that has never
been the view. It is hypothetical only.

Therefore, the model is inconsistent with basic topological concepts.
I have no problem with 4D hyper-models of temporally evolving
geometries.
The fact that you were a child one day in the past and the fact that
that child does not exist anymore as he was defined back then, does not
exclude the fact that you are that child who evolved into an adult and
that you do have coordinates NOW. My sarcastic inquiry is meant to
expose the inconsistency of the model because I demand to know the
whereabouts of that point in the past after it had evolved into an
"adult" coordinate NOW by means of surface topological identities. The
failure to complete the analogy and truncating the logical
consequences, is enough proof of the fallacy and the poverty of the
model.


My life would look like a spring with the axis
roughly perpendicular to the surface. The part
inside was mychildhood, that outside is my
future and where they intersect is 'now'. Why
a spring? Because the Earth orbits the Sun.

Witty remarks about cubes instead of spheres won't
debunk anything either.

[EL]
How about a dumbbell? ;-)
How about a double shelled double vortex, spiralling and compounding
magnanimous-periods of time.


I agree. Perhaps you should read about the
Big Bang model instead.
George

[EL]
Implying that I need to read about the BB, implies that you accuse me
of ignorance.


You seem to think the balloon analogy represents
current thinking. It isn't and was probably never
more than an unproven possibility.

Well, I certainly hope to be found ignorant rather than not, when I am
confronted by loads of ridiculous assertions and inconsistent
analogies.


The analogy is limited but not inconsistent. Of
course if you try to take it too far then it will
fail, but that is what separates an analogy from a
useable model.

George


  #68  
Old June 2nd 05, 02:04 AM
N:dlzc D:aol T:com \(dlzc\)
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Dear Dishman:

"Dishman" wrote in message
ups.com...

N:dlzc D:aol T:com (dlzc) wrote:
Dear George Dishman:


Hello David,


Hi. I hope I am not increasing your "crank response
bandwidth"... ;)

"George Dishman" wrote in message
...

Greg, you and David both seem to be discussing
the discrepancy in the change of radius of the
orbit as a possible direct consequence of the
Hubble flow. I don't quite follow that. If there
was a slight radial expansion, surely it wouldn't
be progressive.


I don't understand the choice of word "progressive"
here George?


Simply that the radius increases year by year
rather than being at a fixed value which is
larger than anticipated.


Couldn't it be both? A proportional "error", proportional to
distance?

Imagine the Moon is moving perpendicularly to the
Earth-Moon line but at a speed which is marginally
too slow to maintain the orbit. In a short time,
it would move closer to the Earth. If you then add
expansion, that could just balance the inwards
motion thus what we would see would be a stable
circular orbit but at a speed fractionally slower
than would be expected for the radius.


I would think that this would obtain an elliptical orbit
over the two+ billions of years that we have records
for the orbit of the Moon. The "necessary deficit"
would be variable over the entire range of orbits...


Yes, I originally started by considering a
circular orbit to simplify the explanation but
lost that part in the edting somehwere :-(
Sorry for the confusion.


Light shined everywhere is not unwelcome.

In reality, the discrepancy would probably be less
than the accuracy of the measurement of GM for the
Earth but in principle, I don't see why you both
think there would be a resulting secular increase
of the radius.


I don't think he was trying to defend this. I think
he was simply trying ot have a modifier added to
my claim that "expansion was observed"...
something like "perhaps", or "it would appear
that". (Sorry if I've caused you grief, Greg.)


I think he was pointing out that there was
a difference between observing a discrepancy
and showing it matches the perturbation
predicted by some hypothesis. In fact that
could also be the same as my question.


OK.

I had a look at the paper David mentioned
and it is only cited by one other:

http://lanl.arxiv.org/abs/gr-qc/0306091

Although much of it is beyond me, equation (63)
seems to be relevant to the discussion.

Hoping you can clue me in ...


I wondered if the local parameters might not be
a function of our position wrt the center of the
Milky Way, and the "dynamo" that powers it.
I see the same issues with my fantasy, as I do
with his third paragraph after this formula,
starting "We want to suggest that each scale
of this hierarchy of structures could have its own
Cosmology, so to speak,". Namely, "how do it
know how to behave"? The parameters very
much "define the metric", so how can the metric
be relied upon to convey the "local" values of
these parameters?

I was simply believing that H0 was the same
everywhere, as the least "ad hoc" solution.


I am not disputing that it is reasonable to
assume that the local value of H_0 would be
similar to, though not necessarily exactly
the same as, the large scale average. What
I am querying is the assumption that it
would produce a secular increase of the
orbital radius.

Taking eqn (63) as a possible alternative,
I might expect that if, in the absence of
expansion, the mean radius was R, then the
inclusion of expansion would increase the
mean radius to R + H_0 * R^2 / c but this
would be constant (other than the known
tidal influence of course).

Does that make the question clearer?


Yes, but...
R is not constant, nor is (H_0 * R^2 / c). Since this doesn't
help, then you are asking a question that I cannot help with.
I'll shut up and listen, to see if anyone else "gets it".

I'll see if I can help paint myself into a corner... The Moon's
period supports one value for R. The instantaneously measured
value *may be* a slightly higher value. So if the Moon stays in
orbit, either (M1 + m2) is increasing faster than we think, the
average gas density in the path is increasing, or the average
radius for the "last orbit" is a little smaller than for the
starting point for the "next orbit" (as determined by LLR).

Lets' see if I provided enough rope to hang myself... ;)

David A. Smith


  #69  
Old June 3rd 05, 12:02 PM
Too Many Kooks Spoil the Brothel
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Default



Too Many Kooks Spoil the Brothel wrote:
Aren't we all!


--------------------

I made a serious error in not cross-posting this to alt.sex the first
time round.

  #70  
Old June 3rd 05, 08:07 PM
George Dishman
external usenet poster
 
Posts: n/a
Default

Dear David,

"N:dlzc D:aol T:com (dlzc)" N: dlzc1 D:cox wrote in
message news:iXsne.1807$Pp.587@fed1read01...
Dear Dishman:

"Dishman" wrote in message
ups.com...

N:dlzc D:aol T:com (dlzc) wrote:
Dear George Dishman:


Hello David,


Hi. I hope I am not increasing your "crank response bandwidth"... ;)


I don't even count you towards it other
than addressing me as "Dear Dishman". ;-)

big snip to reduce bandwidth

I was simply believing that H0 was the same
everywhere, as the least "ad hoc" solution.


I am not disputing that it is reasonable to
assume that the local value of H_0 would be
similar to, though not necessarily exactly
the same as, the large scale average. What
I am querying is the assumption that it
would produce a secular increase of the
orbital radius.

Taking eqn (63) as a possible alternative,
I might expect that if, in the absence of
expansion, the mean radius was R, then the
inclusion of expansion would increase the
mean radius to R + H_0 * R^2 / c but this
would be constant (other than the known
tidal influence of course).

Does that make the question clearer?


Yes, but...
R is not constant, nor is (H_0 * R^2 / c).


OK, I said "mean" to try to get round that but
let me be more formal. Consider the case of a
very small test mass in orbit around a large
dense and perfectly spherical mass M with no
other perturbing bodies in the vicinity and
sufficiently far out to be in the weak-field
regime.

Since this doesn't help, then you are asking a question that I cannot help
with. I'll shut up and listen, to see if anyone else "gets it".

I'll see if I can help paint myself into a corner... The Moon's period
supports one value for R. The instantaneously measured value *may be* a
slightly higher value. So if the Moon stays in orbit, either (M1 + m2) is
increasing faster than we think, the average gas density in the path is
increasing, or the average radius for the "last orbit" is a little smaller
than for the starting point for the "next orbit" (as determined by LLR).

Lets' see if I provided enough rope to hang myself... ;)


Nope, I agree with what you said. My question is,
assuming that we see a rate of increase that is
greater than those factors can explain, why do
you think an additional increase would accrue from
the inclusion of the Hubble expansion. My own
(qualitative) thoughts suggest Hubble expansion
would produce a radius which was larger than
predicted but by a constant amount, not an
additional rate of increase.

That is if it would have any effect at all in
fact since another way of looking at it says
only dark energy would contribute.

I've asked this before but perhaps nobody in the
group knows GR well enough to answer.

best regards
George


 




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