Re: expansion

On Jan 29, 12:05 pm, john280109 <vega...@xxxxxxxxxxxxx> wrote:
On Jan 29, 9:27 am, PD <TheDraperFam...@xxxxxxxxx> wrote:

On Jan 29, 8:58 am, john280109 <vega...@xxxxxxxxxxxxx> wrote:

On Jan 29, 8:07 am, PD <TheDraperFam...@xxxxxxxxx> wrote:

On Jan 29, 7:43 am, john280109 <vega...@xxxxxxxxxxxxx> wrote:

On Jan 29, 1:35 am, Sam Wormley <sworml...@xxxxxxxxx> wrote:

john280109 wrote:
On Jan 28, 4:35 pm, Sam Wormley <sworml...@xxxxxxxxx> wrote:
Michael Moroney wrote:
john280109 <vega...@xxxxxxxxxxxxx> writes:
For there to be expansion where all points are
accelerating away from each other, there has to be
a center. Otherwise you got stuff going all directions.
Therefore if you subscribe to 'expanding universe',
you subscribe to 'we are the center'.
Where is the center of the surface of an inflating balloon, on which all
points are receding from each other?
   All points on the surface of that balloon are equally the center.

Well, it's pretty trivial that a perfect sphere has
a surface that's identical in all directions.
This is not true of a balloon. There's the
little matter of the nozzle. Now, if you paint spots
on your sphere's surface and then expand the
sphere, all the spots *do not* distance themselves equally;
spots directly opposite each other, i.e. the two
axes, will go at the rate of growth of the diameter-
points closer than half circumference will separate
faster.
Oh, now you want to imagine the
balloon's surface to be flat as well?

OK, wait, in order to explain the greater
universe, which we assume to be real, you want to
equate it with something having no center, and also you want
it to have no edge- neither of which conditions has been seen
in anything real to my knowledge.
Plus, you say there's no edge, but you say it's expanding-
expanding with relation to what? Is the whole universe expanding?
And if not, then what?

Gobbledegook- good going physics 2009. Yikes.

john

   <laughing> Interesting how you chose the balloon analogy, implying
   it valid and then tearing it apart. The Universe is flat, homogeneous
   and isotropic on the cosmic scale. And the expansion has no center.

   No Center
     http://www.astro.ucla.edu/~wright/nocenter.html
     http://www.astro.ucla.edu/~wright/infpoint.html

   You must have been tired, John.

+
Tired of bull***, Sam.
"The universe is like an expanding balloon's surface."
Ri..i..g..g..h..h..t!
If the universe's expansion has no center,
then it's the only one. Look up the definition
of expansion. Or is that a 'physics' word?
Like 'spin' where it doesn't
really mean spin 'cause nothing in your model
spins?
'Expansion' that doesn't really mean expansion?

Well, yes, John, this is unfortunately true. The problem is that in
physics we run into things we've never run into before. So when we
describe them, we have a choice: We can invent a new word that means
nothing to anybody but physicists, or we can borrow a familiar word
because the new thing is reminiscent of the old word though not quite
the same, at the risk of confusing lay people who think the old
definition should apply completely. An example is quark "color".
Quarks do not have color in the sense of paint or dye or
characteristic wavelength. But we use the word "color" for this
completely new and foreign property because *some aspects* of this
foreign property are vaguely reminiscent of the way familiar colors
behave. Another example is spin. Now you may think this is unfair and
misleading to lay people. What would you recommend as a policy for how
to describe a totally new and unfamiliar property?

Trust me- your model is physically
impossible. And the universe obeys physical
laws. Every expansion has an edge.

That's simply not true, John. "Every expansion has an edge" is in no
way a physical law. It is YOUR extrapolation from your body of the
familiar. It's not a good idea to call every desirous extrapolation
from the familiar a physical law. You run into obvious mistakes that
way.

It comes from the definition of the word 'expansion'.

The dictionary definition, yes. The word whose definition sprang from
usage that is centuries old, yes. The word that has been *borrowed* by
physicists to describe something that is *not completely like* what is
captured in that centuries-old usage. This happens. Think of it like
slang. People start using "hot" to mean something that has nothing to
do with temperature or any other definition that appears in the
dictionary. Other people get confused because the definition they know
doesn't have anything to do with the conversation that's going on.
Physicists have to do the same thing. They use an old word and attach
it to a new phenomenon, with a meaning that is NOT the same as the way
the word has been used for centuries.

Also, *every* expansion I have ever seen has an edge.
Is that better?

That's no good, John. It's an extrapolation from YOUR common
experience. People who are familiar with mammals in the Americas are
going to want to make the claim that *every* mammal they've ever seen
gives live birth to its young. And then someone holds up an echidna.

Can you point me to an expansion that doesn't
have an edge?

Yes, I gave you an example of one in another thread where you raised
the same concern. Do you remember that?

Very well, I remember it.
You gave me two examples- the expanding
circle with the marks
 where you only measure along the circle between the marks-
similar to the expanding ballon argument where you consider
the surface of the ballon to be flat. Problem is, this is a
fictitious thing *plus* the further out you go the faster
the expansion has to be happening- what happens when
 it hits lightspeed? Does it all just keep going that fast
and pile up in a shell?

And you didn't seem to remember what I told you that c is not a limit
for faraway objects, so no, they do not pile up. This is why I
directed you to that Scientific American article that specifically
dispels the notion that there is a problem with faraway objects piling
up.

The other example has the same problem.
A ruler with no ends. There ain't no such thing,
I'm sorry to say, PD.

Not in your experience, that may be true. But remember the echidna.
I'm sure there were many fellas who leapt to their feet to say, "An
egg-laying mammal? There ain't no such thing! Every mammal I've ever
heard of gives live birth to its young!"


Point me to a *real* expansion that has no edge.



Your points about physics needing to
'borrow' words to describe undescribable things
and using the word differently- why use 'expansion',
then?

Because the alternative is to invent a wholly new word with a special
definition, and then no one but physicists will know what that means.
(This has been done in the past, by the way. Newton used the quantity
called momentum, but he didn't have the word "momentum". So he used
the term "quantity of motion", which is of course easily confused with
a whole bunch of other meanings that he did not intend. So a special
word was invented.)

Would you prefer that a special word be invented, like
"continuogenesis" so that you won't be confused?

You see, PD, if you can discount the edge,
then the whole thing can just be getting more dilute.

Yes, that's true.

And of course, there's no center. But if there's no
edge, then what is it expanding relative to?

It's like I described to you earlier. If the marks on a line are all
receding from each other, there is NO NEED to ask what the edges are
doing. You do not need to have the additional information from the
edges to know that the expansion is happening. It is extraneous
baggage.

As I said before; the further out you go,
the faster the stuff has to be going. You very quickly get
to lightspeed. Then what?

It's not a limit. Please read the Scientific American article.


It's exactly as if every galaxy and bit of matter is
shrinking steadily.

Yes, alternatively so. But we have a mathematically sound physical
model that says precisely that it *should* expand. We don't have a
mathematically sound physical model that says that every galaxy and
bit of matter is shrinking steadily. This is an important distinction,
even if at the 90,000 ft level the two look equivalent. They are not
equivalent.

Except the mathematically sound model is built
on the presumption of an initial Big Bang?

No, it's NOT built on the presumption of the Big Bang. General
relativity was developed before there was ever a hint of the Big Bang.
When general relativity was developed, physicists and astronomers all
thought the universe was static and eternal. And yet general
relativity predicted that the universe would expand. This was viewed
as a *problem* with general relativity, and Einstein even took
measures to try to *fix* the theory so that it wouldn't make that
prediction. And then, lo and behold, almost 15 years LATER, it was
discovered that the universe gave evidence of expanding. This was one
of those "son of a gun" things that made people believe that
relativity might be right after all.

Another fictitious thing.

 How about this?
 The universe is a note. The note
 is constantly creating resonating notes,
 each in the shape of 3D fractals based on
 shapes like galaxies being made from other
 shapes like galaxies. As soon as each of these
 resonating notes is born, it starts shrinking and
 continues to do so until it gets taken over by
 the background hum, like all notes do.
 So, to each of these notes, everything else would
 be steadily receding.

 We'll call it, The Shrinking Note Theory  or SNOT

 john

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