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#11
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Looking into the past with a telescope
cantseeboo wrote:
Starboard (Errol) e-mailed me the following replies. Said that the board would not accept his post for some reason.. I'm posting for him... cantseeboo........................................ .................................................. . I guess that's the same as asking where's the universe's center of gravity.... The Universe has no true center. The frames of reference we are used to on the earth are only illusions. In the universe at large no two observers (people) can be expected to keep the same time much less agree where to measure everything from. When the universe came into being, it began expanding into, what I first heard referred to by Prof. Hawking, nothingness. But suppose someone viewed said expanse from that area of nothingness. Could he say "I saw the universe expand away from some point in the universe's interior."? Would it be the same as asking "if there were a big crunch, to what point in the universe would all matter crunch to?" No. That's a nonsensical question. There can be no observer outside watching. So there can be no answer. That's like asking, "Assuming the earth is flat, how deep is the dirt you are standing on?" The invalid assumption invalidates the question. Imagine that you live on the earth but think it is flat. The flatness of the earth is an illusion. For a person who sees the earth in terms of this illusion, where then is the center of the earth? Where is the center? Seems obvious, but don't you think difficulties arise when one states that the flatness expanded from a single point in the past? I don't see your point. Mixing my metaphor back into the real picture isn't useful. In a very real sense the position of each observer is the center of the universe. Relativity teaches us that everything is relative--which means there are no absolutes. Agreed that relativity does teach us that there is no preferred place from which to take a measurement, however, isn't it also reasonable to assume that the universe did expand away from some point in the universe's interior in the distant past? No, not according the current cosmology (which is the only one that adequately describes the bulk of the available observational evidence). In my opinion, astronomers do the world an injustice by describing the Big Bang as something that happened long ago. The universe *is* the big bang, expanding all around us; they are one in the same. And no, you don't need a center in order for there to be an expansion, nor do you need something (even nothingness) to expand into. Again, this is earth-centered 3-dimensional thinking (see my flat earth analogy). In the three-dimensional world that we perceive there is no center and there never was one. The flat earth analogy isn't perfect--an improvement is to imagine a two-dimensional creature who cannot observe the third dimension at all (in this case the third dimension is "up and down"; the creature can only know north/south and east/west). It's not just ignorance that would keep such a creature from "seeing" the center of the earth. To observe the center of the round earth would require "seeing" in a dimension beyond their direct reality, something they could only weakly imagine--or describe using mathematics. It is important to recall that these weak analogies are only important as a means of explaining the mathematics to those who do not "speak" the language of mathematics. It is in the mathematics that cosmology truly lies. Greg -- Greg Crinklaw Astronomical Software Developer Cloudcroft, New Mexico, USA (33N, 106W, 2700m) SkyTools: http://www.skyhound.com/cs.html Observing: http://www.skyhound.com/sh/skyhound.html Comets: http://www.skyhound.com/sh/comets.html To reply take out your eye |
#12
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Looking into the past with a telescope
You are getting replies from people who look out on the celestial
arena like this - http://www.opencourse.info/astronomy...ion_stars_sun/ celestial_sphere_anim.gif Ask them to locate an external galaxy and they will cheerfully give you a constellational reference borrowed from the cartoon framework above. What you do is start with basic centers of rotation.The daily cycle determines that you are on a rotating Earth and has the most immediate impact on your existence. The next center of rotation is to appreciate your orbital motion around the Sun.This you can do by looking at the following time lapse footage of the faster Earth overtaking the slower forward moving outer planets - http://antwrp.gsfc.nasa.gov/apod/ima...2000_tezel.gif The next center of rotation is the motion of the Earth along with the entire solar system around the central galactic axis.As this great sweeping motion is so inperceptible,except in principle,what you should see is that the local forground stars would move against the position of the external galaxies. There may be greater centers of rotation beyond this but that would be for a different era.In this era they cannot even express the basic rotation of the Earth on its axis in correct geometric terms.Every- point-is -the-center-of-an -expanding-universe indeed !,do you ever listen to yourselves.It is so anti-astronomy in denying cyclical motions and at its core is the silly 17th century maneuver that paved the way for its emergence - "... our clocks kept so good a correspondence with the Heavens that I doubt it not but they would prove the revolutions of the Earth to be isochronical... " Flamsteed using Sirius as a celestial sphere gauge Those who are perfectly happy to bypass all the centers of rotation from which the great astronomers operated, to make a ridiculous sweeping gesture about the rest of the universe simply have little sense of how dumb their statements actually are .The great Copernican insight which uses the observed motion of the other planets to extract the concept that the Earth has an orbital motion turns into a nonsensical principle in their hands. http://en.wikipedia.org/wiki/Copernican_principle Personally I On Jan 26, 8:39 pm, "cantseeboo" wrote: Starboard (Errol) e-mailed me the following replies. Said that the board would not accept his post for some reason.. I'm posting for him... cantseeboo........................................ ..........................*....................... ... I guess that's the same as asking where's the universe's center of gravity.... The Universe has no true center. The frames of reference we are used to on the earth are only illusions. In the universe at large no two observers (people) can be expected to keep the same time much less agree where to measure everything from.When the universe came into being, it began expanding into, what I first heard referred to by Prof. Hawking, nothingness. But suppose someone viewed said expanse from that area of nothingness. Could he say "I saw the universe expand away from some point in the universe's interior."? Would it be the same as asking "if there were a big crunch, to what point in the universe would all matter crunch to?" Imagine that you live on the earth but think it is flat. The flatness of the earth is an illusion. For a person who sees the earth in terms of this illusion, where then is the center of the earth? Where is the center?Seems obvious, but don't you think difficulties arise when one states that the flatness expanded from a single point in the past? In a very real sense the position of each observer is the center of the universe. Relativity teaches us that everything is relative--which means there are no absolutes.Agreed that relativity does teach us that there is no preferred place from which to take a measurement, however, isn't it also reasonable to assume that the universe did expand away from some point in the universe's interior in the distant past? Errol pasnola |
#13
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Looking into the past with a telescope
Starboard wrote: Would you like to be the first to answer this question correctly. You know that our solar system is moving with the rest of the local stars around the Milky Way axis. If you look at an external galaxy,say the Whirlpool galaxy,what would you expect to happen after 1 million years ?.Remember the foreground stars of the Milky Way are orbiting the galactic axis therefore we are moving like a system on a giant carousel. That seems true for indicating the direction to intergalaxy objects with respect to intragalaxy objects, but is that true for indicating direction of intergalaxy objects with respect to other intergalaxy objects? The motion of the local forground Milky Way stars ,including the motion of our system,will cause the the position of the external galaxies to change just as you would see external objects to change their position against other objects on a carousel. Of course you use constellational geometry to describe the position of the external galaxies - http://www.opencourse.info/astronomy...ion_stars_sun/ celestial_sphere_anim.gif Where there should be an exciting astronomical attempt to show how the foreground stars change by using the external positions of the galaxies there is nothing.There are plent of guys looking for 'dark' things and all the other kitch of celestial sphere concepts but none given towards using actual celestial objects and their known motions. There is an added complication based on supernova data and how the effect Ole Romer noticed at the heliocentric level becomes enormous at the level of galactic orbital motion and the position of the external galaxies.Considering I have yet to receive an affirmation of how we see our own heliocentric motion in a forum which cheerfully promotes any recognition of astronomical centers,well.... Don't listen to me, I'm tired as old hell from staying up late putting together the NEW XT-12 Intelliscope.... Yeee doggie! Errol pasnola Errol pasnola |
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Looking into the past with a telescope
On Jan 26, 9:26 pm, Sam Wormley wrote: cantseeboo wrote: Since the distribution of galaxies on the large scale is isotropic, .... Where do astronomers think the Milky Way is *in the Universe*? Towards the center? Close to the edge? Any idea? Do astronomers know where the universal center is? I guess that's the same as asking where's the universe's center of gravity....Maybe not.... No Center http://www.astro.ucla.edu/~wright/nocenter.html Also see Ned Wright's Cosmology Tutorial http://www.astro.ucla.edu/~wright/cosmolog.htm http://www.astro.ucla.edu/~wright/cosmology_faq.html WMAP: Foundations of the Big Bang theory http://map.gsfc.nasa.gov/m_uni.html WMAP: Tests of Big Bang Cosmology http://map.gsfc.nasa.gov/m_uni/uni_101bbtest.html Thanks for that Sam,every chance I can get to show that the original reason for 'curving' the universe was the lament that light leaving stars would go to waste - " This view is not in harmony with the theory of Newton. The latter theory rather requires that the universe should have a kind of centre in which the density of the stars is a maximum, and that as we proceed outwards from this centre the group-density of the stars should diminish, until finally, at great distances, it is succeeded by an infinite region of emptiness. The stellar universe ought to be a finite island in the infinite ocean of space. This conception is in itself not very satisfactory. It is still less satisfactory because it leads to the result that the light emitted by the stars and also individual stars of the stellar system are perpetually passing out into infinite space, never to return, and without ever again coming into interaction with other objects of nature. Such a finite material universe would be destined to become gradually but systematically impoverished. " http://www.bartleby.com/173/30.html The poor guy was speaking before they discovered these stellar island groups we now know as galaxies,seeing him reject the idea of a stellar center and there are billions of them sure looks funny to 21st century eyes. As for light leaving stars going to waste,people are supposed to laugh themselves silly yet 100 years later the majority are still into 'curved space ' and making huge generalised statements about universal structure.If they first recognised the celestial sphere core at the center of Newton's work they would immediately recognise where this exotic trash is coming from. This is not hugely complicated material,this stuff as easy to handle with familiarity however you can only remain with the exotic celestial sphere symptoms of the last century for a short while.There is too much productive work to do to wastee time on childish notions of the last century. |
#15
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Looking into the past with a telescope
On 26 Jan 2007 12:39:14 -0800, "cantseeboo"
wrote: Agreed that relativity does teach us that there is no preferred place from which to take a measurement, however, isn't it also reasonable to assume that the universe did expand away from some point in the universe's interior in the distant past? You should purge yourself of the mental picture of the Universe expanding from a point. The pretty animations you see in science films of an explosion from a point flying outward in all directions is frankly a terrible illustration. I wish film producers would stop with that... Think of the Universe instead as the expanding surface of a balloon. Anything inside or outside of its surface is nothingness and doesn't exist. So as the balloon expands, where is the center on the surface? This should help you visualize that such a center point doesn't exist, and never existed. In fact, at the moment of birth of the balloon surface when it was infinitely small, every point of the surface was coincident. --- Michael McCulloch |
#16
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Looking into the past with a telescope
In three dimensions, there is no center. Does it have a center in some higher dimension? Errol |
#17
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Looking into the past with a telescope
No. That's a nonsensical question. There can be no observer outside
watching. So there can be no answer. That's like asking, "Assuming the earth is flat, how deep is the dirt you are standing on?" The invalid assumption invalidates the question. I didn't see it as a nonsensical question, but as a continuation of a nonsensical analogy. I guess it's all relative. Imagine that you live on the earth but think it is flat. The flatness of the earth is an illusion. For a person who sees the earth in terms of this illusion, where then is the center of the earth? Where is the center? Seems obvious, but don't you think difficulties arise when one states that the flatness expanded from a single point in the past? I don't see your point. Mixing my metaphor back into the real picture isn't useful. Simple. I'm terms of this discussion, I'm the flat Earth guy and you're telling me that it all came from a single point in the past. You can see how I would have a problem with that. The response was meant to illustrate where I am intellectually with this whole thing. I like to think that things can be expressed in terms of three spatial dimensions and time as a forth. I have a real problem letting go of that. In a very real sense the position of each observer is the center of the universe. Relativity teaches us that everything is relative--which means there are no absolutes. Agreed that relativity does teach us that there is no preferred place from which to take a measurement, however, isn't it also reasonable to assume that the universe did expand away from some point in the universe's interior in the distant past? No, not according the current cosmology (which is the only one that adequately describes the bulk of the available observational evidence). And that's fine. It's what the cosmologist should be doing - pursuing a model that describes what they observe empirically. As far as Relativity preventing there from being a universal center, I don't see it. I only see that Relativity prevents us from finding it using yard sticks and stopwatches. In my opinion, astronomers do the world an injustice by describing the Big Bang as something that happened long ago. The universe *is* the big bang, expanding all around us; they are one in the same. And no, you don't need a center in order for there to be an expansion, nor do you need something (even nothingness) to expand into. Again, this is earth-centered 3-dimensional thinking (see my flat earth analogy). In the three-dimensional world that we perceive there is no center and there never was one. Fair enough. But in what dimension does the universe have a center? The flat earth analogy isn't perfect--an improvement is to imagine a two-dimensional creature who cannot observe the third dimension at all (in this case the third dimension is "up and down"; the creature can only know north/south and east/west). It's not just ignorance that would keep such a creature from "seeing" the center of the earth. To observe the center of the round earth would require "seeing" in a dimension beyond their direct reality, something they could only weakly imagine--or describe using mathematics. It is important to recall that these weak analogies are only important as a means of explaining the mathematics to those who do not "speak" the language of mathematics. It is in the mathematics that cosmology truly lies. Great, as long as what is observed coincides with the math model. I'm worried that portions of the scientific community will begin to propose/accept theories based mostly on mathematical models. Like the non-falsify-able string theory. This mess is so far over my head; my background is electrical. I only got interested in astronomy a little over a year ago. Just trying to get a slightly better understanding of the cosmos. Thanks for all your feedback. Errol |
#18
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Looking into the past with a telescope
On Jan 28, 5:34 am, Michael McCulloch wrote: On 26 Jan 2007 12:39:14 -0800, "cantseeboo" wrote: Agreed that relativity does teach us that there is no preferred place from which to take a measurement, however, isn't it also reasonable to assume that the universe did expand away from some point in the universe's interior in the distant past?You should purge yourself of the mental picture of the Universe expanding from a point. The pretty animations you see in science films of an explosion from a point flying outward in all directions is frankly a terrible illustration. I wish film producers would stop with that... After telling the hapless reader of the terrible mental picture you then forward this ..... Think of the Universe instead as the expanding surface of a balloon. Anything inside or outside of its surface is nothingness and doesn't exist. Funny,funny,funny, something like this - http://www.opencourse.info/astronomy...ion_stars_sun/ celestial_sphere_anim.gif So as the balloon expands, where is the center on the surface? This should help you visualize that such a center point doesn't exist, and never existed. In fact, at the moment of birth of the balloon surface when it was infinitely small, every point of the surface was coincident. --- Michael McCulloch To believe something like this you have to be a very 'special' person,anyone else would be looking to find out what went wrong and how astronomy descended into a celestial sphere bubble.The thing is that nobody objects,nay,they promote this most ridiculous copncept of the majesty of the celestial arena as if it is were the most profound concept possible. Is there nobody ashamed enough to burst this particular celestial sphere balloon ?. |
#19
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Looking into the past with a telescope
Starboard wrote:
Does it have a center in some higher dimension? It might, but not necessarily. The universe need not exhibit radial symmetry. -- 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 |
#20
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Looking into the past with a telescope
On Sun, 28 Jan 2007 08:57:16 -0800 (PST), (Brian Tung)
wrote: It might, but not necessarily. The universe need not exhibit radial symmetry. Is radial symmetry a condition of having a center? I would think the Universe must have a center in some higher dimension, regardless of its shape and topology (even if that center isn't a simple point). _________________________________________________ Chris L Peterson Cloudbait Observatory http://www.cloudbait.com |
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