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Looking into the past with a telescope



 
 
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  #51  
Old January 29th 07, 11:52 PM posted to sci.astro.amateur
Ioannis
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Default Looking into the past with a telescope

"Chris L Peterson" wrote in message
...

On Mon, 29 Jan 2007 23:39:30 +0200, "Ioannis"
wrote:

To me, it looks as though "the edge" of the universe around any individual
observer is simply a theoretical sphere of radius c*t where t is the age of
the observer and c is the speed of light.


You need to distinguish between the edge of the Universe, and the edge
of the observable Universe. They aren't the same thing. You are
describing the latter.


Sorry, I fail to understand any such difference. FOR ME, the universe IS my
observable universe. The same applies to any other observer. As such, any
other universe (different from one's /observable/ universe) looks more like of
a mental construct than reality, at least to me.

I suspect that by what you call "the Universe", you may mean that vast (r~=13
billion ly) mental construct which sits there independent of human perception.
I do not recognise the existence of any such construct separated from human
perception/consciousness.

[snip]

Chris L Peterson

--
I.N. Galidakis
http://ioannis.virtualcomposer2000.com/

  #52  
Old January 29th 07, 11:53 PM posted to sci.astro.amateur
Starlord
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Posts: 1,908
Default Looking into the past with a telescope

Hell all it takes for the CFH is a screw driver now!


--
There are those who believe that life here, began out there, far across the
universe, with tribes of humans, who may have been the forefathers of the
Egyptians, or the Toltecs, or the Mayans. Some believe that they may yet be
brothers of man, who even now fight to survive, somewhere beyond the
heavens.


The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html


"Iordani" wrote in message
...
Chris L Peterson wrote:


(I remember an original Outer Limits episode about a being that could
"turn" in the fourth dimension, allowing it to appear and disappear
anywhere in the 3D world as if by magic.)


Indeed, my reading glasses and car keys perform this trick all the
time...

Very interesting thread BTW.



  #53  
Old January 29th 07, 11:59 PM posted to sci.astro.amateur
Starlord
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Posts: 1,908
Default Looking into the past with a telescope

Ofcourse there is only one true way to see what is at the very edge of
universe, and it's in the mind of every human, only some of them lack the
powers to be able to use that section of their mind, and Sci-Fi writters
have used it to the Nth dregree some say.

and when you combine a true Sci-Fi man with an Astronomer Man and you get
the being known as "Starlord". ;}


--
There are those who believe that life here, began out there, far across the
universe, with tribes of humans, who may have been the forefathers of the
Egyptians, or the Toltecs, or the Mayans. Some believe that they may yet be
brothers of man, who even now fight to survive, somewhere beyond the
heavens.


The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html


"Michael McCulloch" wrote in message
...
On Mon, 29 Jan 2007 15:31:04 -0500, I wrote:

On Sun, 28 Jan 2007 15:28:41 -0500, Davoud wrote:

The problem is the edge.


Why? If you were close to the edge you would never even sense it in
any way since you only exist in our space-time, and any edge is by
definition outside of your existence.

Any edge is beyond our intuitive powers to comprehend.


Well, on second thought I will backtrack on this and say the actual
properties of any edge would be beyond our powers to imagine, however
we can use analogies to assist our comprehension.

Some theories even suggest the edge of the Universe is only a
sub-atomic distance from you at this very minute!


To expand on this in the context of "balloon world" just for fun:

Imagine that you are a transcendent being that lives in 3D space (God
of the balloon world if you will :-). You observe the inhabitants on
the surface of balloon world and see the boundary or edge of their
Universe. It doesn't appear mysterious or anything, just that the
inhabitants of balloon world only move around on the surface of the
balloon.

So the balloon world appears dimensionless for all practical purposes
in the 3rd dimension to you as God. For sake of argument though, let's
say maybe balloon world's surface does have a dimension, but it is
sub-atomic in scale. So the balloon world inhabitants do not sense it
at their macro scale (but their scientists have guessed that perhaps
this is the case).

In the course of scientific progress, the balloon world inhabitants
somehow come up with a theory that postulates a 3rd spatial dimension
beyond the two dimensions in which they exist. However, they cannot
visualize or observe the actual "edge" of their Universe. But, they
come up with an analogy: they think of "line world". The inhabitants
of line world only exist in one dimension, the balloon world
inhabitants would be Gods for them, and the balloon world scientists
use the analogy to comprehend dimensions beyond their own.

Furthermore, what if there are many balloon worlds consisting of
concentric balloon surfaces that never intersect but are only
sub-atomic distances from each other. As God I could see all of the
balloon worlds, but the inhabitants of each never sense the existence
of all the other balloon worlds even though they are only at
sub-atomic distances.

So as an astronaut in balloon world, I could fly my spaceship for
eternity and never find the edge of my balloon. What a waste, since
all that time the edge was just a sub-atomic distance away!

Many of you will recognize this as M-Theory. :-) Of course, most
books present it in the context of 'branes', whereby the analogy
becomes multiple Universes that exist on infinite sheets that are
parallel in a higher dimension. I prefer that form of the analogy in
some ways since it illustrates how our Universe could be flat (which
is what the current data suggests) and appear infinite in extent.

---
Michael McCulloch



  #54  
Old January 30th 07, 12:13 AM posted to sci.astro.amateur
Brian Tung[_1_]
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Posts: 755
Default Looking into the past with a telescope

Ioannis wrote:
Sorry, I fail to understand any such difference. FOR ME, the universe
IS my observable universe. The same applies to any other observer. As
such, any other universe (different from one's /observable/ universe)
looks more like of a mental construct than reality, at least to me.


Again, let us drop down one dimension, and suppose that the universe is
a simple sphere. Suppose this universe has age T, and radius R cT;
that is, its diameter is increasing at much faster than the speed of
light. (This is not a violation of the principles of relativity.)

In that case, any individual within the universe cannot see the entire
universe; all he can see is a disc centered on him with radius cT. The
edge of this disc is a logical (i.e., non-physical boundary) edge, and
this is the one you're talking about.

The "edge" that Chris (and earlier Davoud) were talking about is a
different one. I don't think "edge" is the right term, for one should
not think of the *interior* of this spherical universe as being part of
it. The universe proper contains only the surface of the sphere. But
inasmuch as you think of the universe as a kind of inflating balloon,
this edge is the surface of the balloon, not a boundary drawn logically
on the surface.

I suspect that by what you call "the Universe", you may mean that vast
(r~=13 billion ly) mental construct which sits there independent of
human perception. I do not recognise the existence of any such
construct separated from human perception/consciousness.


If I understand you correctly, that is an odd perspective. You mean
that you do not recognize the existence of that which you cannot detect?
I doubt that you mean that--could you clarify?

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
  #55  
Old January 30th 07, 12:53 AM posted to sci.astro.amateur
Ioannis
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Posts: 216
Default Looking into the past with a telescope

"Brian Tung" wrote in message
...
[snip]

I suspect that by what you call "the Universe", you may mean that vast
(r~=13 billion ly) mental construct which sits there independent of
human perception. I do not recognise the existence of any such
construct separated from human perception/consciousness.


If I understand you correctly, that is an odd perspective. You mean
that you do not recognize the existence of that which you cannot detect?


That's right. Your "detect", above, is my "seeing with my own eyes".
Information from an object outside my observable universe (r=c*t) hasn't
reached me yet, therefore it's as good as non-existent (for me).

I doubt that you mean that--could you clarify?


You understood correctly. I don't know what "universe" means to you and Chris,
but to me it is THAT, parts of which I can see NOW. Never mind the fact that
what I see may be light from the construct's past.

--
Brian Tung

--
I.N. Galidakis
http://ioannis.virtualcomposer2000.com/

  #56  
Old January 30th 07, 12:55 AM posted to sci.astro.amateur
Chris L Peterson
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Posts: 10,007
Default Looking into the past with a telescope

On Tue, 30 Jan 2007 00:52:59 +0200, "Ioannis"
wrote:

Sorry, I fail to understand any such difference. FOR ME, the universe IS my
observable universe. The same applies to any other observer. As such, any
other universe (different from one's /observable/ universe) looks more like of
a mental construct than reality, at least to me.


Hmmm... when you are at home with the curtains drawn, does the rest of
the world cease to exist for you? g


I suspect that by what you call "the Universe", you may mean that vast (r~=13
billion ly) mental construct which sits there independent of human perception.
I do not recognise the existence of any such construct separated from human
perception/consciousness.


The Universe is almost certainly much bigger than 13 billion ly in
"diameter" (I use that term loosely, because I don't think the Universe
is a 3D construct). The part of the Universe that is beyond our horizon
isn't another universe, it's just a part we can't see (there are
theories that posit other universes entirely). But what we _can_ see
allows us to make reasonable inferences about what we can't. I don't
think it's reasonable to ignore the existence of majority of the
Universe.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
  #57  
Old January 30th 07, 01:20 AM posted to sci.astro.amateur
Ioannis
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Posts: 216
Default Looking into the past with a telescope

"Chris L Peterson" wrote in message
...

On Tue, 30 Jan 2007 00:52:59 +0200, "Ioannis"
wrote:

Sorry, I fail to understand any such difference. FOR ME, the universe IS my
observable universe. The same applies to any other observer. As such, any
other universe (different from one's /observable/ universe) looks more like

of
a mental construct than reality, at least to me.


Hmmm... when you are at home with the curtains drawn, does the rest of
the world cease to exist for you? g


I don't know WHAT it does. For all I know, the entire universe may fall into
some sort of suspended animation while I sleep and then reappear when I wake
up. Since there is no way to know, your question doesn't make much sense :-)

[snip]

The Universe is almost certainly much bigger than 13 billion ly in
"diameter" (I use that term loosely, because I don't think the Universe
is a 3D construct).


There we go again... Your "Universe" is a mental construct in your mind.
Sorry, but we disagree on what is "existent" and what is not. I repeat: I do
not recognise your "Universe" except as a mental construct, to which you have
arbitrarily given the property to be independent of consciousness and
perception. I don't agree!

And that was "r"=13 billion ly's. "Radius". Not diameter :-)

[snip]

Chris L Peterson

--
I.N. Galidakis
http://ioannis.virtualcomposer2000.com/

  #58  
Old January 30th 07, 01:21 AM posted to sci.astro.amateur
Brian Tung[_1_]
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Posts: 755
Default Looking into the past with a telescope

Ioannis wrote:
That's right. Your "detect", above, is my "seeing with my own eyes".
Information from an object outside my observable universe (r=c*t) hasn't
reached me yet, therefore it's as good as non-existent (for me).


By that reasoning, parts of the universe flicker into existence at the
precise moment that you detect them. How is it that the objects there
emitted the photons that allowed you to detect them? How did the
photons traverse space that did not exist at the time?

I'm not trying to put you on the spot; I'm just having trouble seeing
the benefit of equating "detected" (*not* "detectable") with "existent."
It's something you're apparently aware of, so I assume you are OK with
this schema. Suppose you have a brick in front of you, which you cannot
actually touch. Does the interior of the brick not exist for you? For
that matter, does the brick exist, or just the photons that reach your
eye, reflected from the (putative) brick?

You understood correctly. I don't know what "universe" means to you and
Chris, but to me it is THAT, parts of which I can see NOW. Never mind
the fact that what I see may be light from the construct's past.


That seems like a heck of a thing to "never mind." At the least, it
would have prevented the current level of understanding of the Big Bang.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
  #59  
Old January 30th 07, 01:24 AM posted to sci.astro.amateur
Brian Tung[_1_]
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Posts: 755
Default Looking into the past with a telescope

Chris L Peterson wrote:
The Universe is almost certainly much bigger than 13 billion ly in
"diameter" (I use that term loosely, because I don't think the Universe
is a 3D construct).


You don't need the universe to be three-dimensional to use "diameter"
rigorously. It just has to have a consistent metric; the diameter is
then simply the greatest distance between any two points.

Admittedly, consistency is a problem, since you don't measure simply
between two spatial points; you have to measure between events. But
three-dimensionality is surely not the problem.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
  #60  
Old January 30th 07, 01:46 AM posted to sci.astro.amateur
Ioannis
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Posts: 216
Default Looking into the past with a telescope

"Brian Tung" wrote in message
...

Ioannis wrote:
That's right. Your "detect", above, is my "seeing with my own eyes".
Information from an object outside my observable universe (r=c*t) hasn't
reached me yet, therefore it's as good as non-existent (for me).


By that reasoning, parts of the universe flicker into existence at the
precise moment that you detect them.


Sort of. An object "comes" into existence when its photons reach the observer.
Alternatively, you could imagine the observer surveying "reality" at the speed
of c. (d(ct)/dt). Once an object is "detected", consciousness makes it
permanent via memory. In a sense, reality's "consistency" is the result of our
collective consciousness' "memory". More on that later.

How is it that the objects there
emitted the photons that allowed you to detect them? How did the
photons traverse space that did not exist at the time?


I believe that for any observer there's somebody(something) beyond him
who(which) acts as a sustainer reality. For example, I was not born into the
void. I was born inside my mother's reality. In a sense, this reality acted as
a sustainer for my consciousness, and gave the seeds of the "space" which
later MY consciousness started surveying. Think of it sort of like the shells
of an onion.

I'm not trying to put you on the spot; I'm just having trouble seeing
the benefit of equating "detected" (*not* "detectable") with "existent."
It's something you're apparently aware of, so I assume you are OK with
this schema. Suppose you have a brick in front of you, which you cannot
actually touch. Does the interior of the brick not exist for you?


No, unless I break the brick apart and look at its exact contents. Here memory
helps. It "reconstructs" the interior of the brick, based on my past
experience with other similar bricks. If I see a brick for the first time, I
sure as heck won't know what's inside, but somebody else may well do. Your
question would be more interesting if you asked, "what if /nobody/ has/d
dissected a brick? Does THEN the interior of the brick exist?"

For
that matter, does the brick exist, or just the photons that reach your
eye, reflected from the (putative) brick?


See above, re memory.

You understood correctly. I don't know what "universe" means to you and
Chris, but to me it is THAT, parts of which I can see NOW. Never mind
the fact that what I see may be light from the construct's past.


That seems like a heck of a thing to "never mind." At the least, it
would have prevented the current level of understanding of the Big Bang.


As far as I am concerned, the big bang was my birth. Nothing prior to my birth
date can be verified directly by me or my consciousness, so the question of
the big bang which YOU mean, for me doesn't make much sense. The entire
history of humankind prior to anyone's birth, is taken by that observer
entirely on faith.

Anyway, let's stop this discussion, because we are going into metaphysics,
which is OT. I am working on all this as we speak. When I finish the article,
you are welcome to take a look at my website.

--
Brian Tung

--
I.N. Galidakis
http://ioannis.virtualcomposer2000.com/

 




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