APOD: The CMB Cold Spot (2011 Mar 21)

Comments and questions about the APOD on the main view screen.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Indigo_Sunrise » Tue Mar 22, 2011 3:08 pm

bystander wrote:If ir·regard·less were a word, it probably wouldn't mean what you want it to mean. The suffix ·less means without. So regard·less means, literally, without regard. The prefix ir· means not. So ir·regard·less means not without regard, or, removing the double negative, with regard. Probably quite the opposite of the meaning you were trying to convey.

What is an axium? :?

^^^THIS^^^


A ton of thanks, bystander!

And I'm wondering what an 'axium' is, too........ :?
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by owlice » Tue Mar 22, 2011 3:26 pm

NoelC wrote:(the much more difficult to say word)
lol!! Oh, thanks for that!

And for the word, too. My teenager doesn't use "za," and I suspect he wouldn't even consider using it in Scrabble (wha-ha-ha-ha!). Neither would it have occurred to me.... until now! :mrgreen: (Too bad his spring break is over and he's already back at school!)
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by owlice » Tue Mar 22, 2011 3:30 pm

Indigo_Sunrise wrote:And I'm wondering what an 'axium' is, too........ :?
14 points if you can get away with it and you can't take advantage of any of the premium squares.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Indigo_Sunrise » Tue Mar 22, 2011 4:33 pm

Hmmmmmmmmm.....


*diggingoutthescrabbleboard*



:lol:
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by BMAONE23 » Tue Mar 22, 2011 4:49 pm

Indigo_Sunrise wrote:
bystander wrote:If ir·regard·less were a word, it probably wouldn't mean what you want it to mean. The suffix ·less means without. So regard·less means, literally, without regard. The prefix ir· means not. So ir·regard·less means not without regard, or, removing the double negative, with regard. Probably quite the opposite of the meaning you were trying to convey.

What is an axium? :?

^^^THIS^^^


A ton of thanks, bystander!

And I'm wondering what an 'axium' is, too........ :?
I thought Axium was what you did when you had a quession

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by rstevenson » Tue Mar 22, 2011 5:17 pm

NoelC wrote:RIP
Surely you mean R.I.P.? :mrgreen:

Rob

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Beyond » Tue Mar 22, 2011 5:25 pm

Whats a few ...'s amongst friends :?:
To find the Truth, you must go Beyond.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by NoelC » Wed Mar 23, 2011 5:13 am

rstevenson wrote:
NoelC wrote:RIP
Surely you mean R.I.P.? :mrgreen:
From http://dictionary.reference.com/browse/RIP (emphasis mine):
R.I.P. 
  1. may he or she rest in peace. Origin:
    < Latin requiēscat in pāce
  2. may they rest in peace. Origin:
    < Latin requiēscant in pāce
Also, RIP
Sometimes I do make mistakes though... Why, just the other day I thought I was wrong about something, but it turned out I was mistaken! :P

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Omphaloskepsis

Post by neufer » Wed Mar 23, 2011 8:34 pm

DonQHoti wrote:
Maybe the Cold Spot is the omphalus.
http://en.wikipedia.org/wiki/Omphalos wrote: <<An omphalos is an ancient religious stone artifact, or baetylus. In Greek, the word omphalos means "navel" (compare the name of Queen Omphale). According to the ancient Greeks, Zeus sent out two eagles to fly across the world to meet at its center, the "navel" of the world. Omphalos stones used to denote this point were erected in several areas surrounding the Mediterranean Sea; the most famous of those was at the oracle in Delphi. The plant genus Omphalodes in the family Boraginaceae is commonly called navelwort. It is also the name of the stone given to Cronus in Zeus' place in Greek mythology.

Most accounts locate the Omphalos in the temple adyton near the Pythia. The stone itself (which may have been a copy) has a carving of a knotted net covering its surface, and has a hollow centre, which widens towards its base (illustrated, to the right).

Omphalos stones were said to allow direct communication with the gods. Leicester Holland (1933) has suggested that the stone was hollow to channel intoxicating vapours breathed by the Oracle. Erwin Rohde wrote that the Python at Delphi was an earth spirit, who was conquered by Apollo, and buried under the Omphalos, and that it is a case of one god setting up his temple on the grave of another.

Christian destruction of the site in the fourth century at the order of Emperors Theodosius I and Arcadius makes all suggestions about its use tentative.

In the Church of the Holy Sepulchre in Jerusalem there is also an omphalos. The existence of this stone is based upon the medieval cosmology which saw Jerusalem as the spiritual if not geographical center of the world (see T and O map). This tradition is likely based on an ancient Jewish tradition that saw Jerusalem as the navel of the world.[1] In the Jewish tradition, the Ark in the Temple in Jerusalem, through which God revealed himself to His people, rested on the Foundation stone marking the "navel of world". (This Jewish tradition is known to have begun in Hellenistic times, when Jews were already quite familiar with Greek culture - and thus, might be a deliberate emulation of and competition with the above tradition regarding Delphi).

In chapter 1 of James Joyce's Ulysses Buck Mulligan describes his home in a Martello tower as an omphalos:
  • Billy Pitt had them built, Buck Mulligan said, when the French were on the sea. But ours is the OMPHALOS.
In chapter 14, Mulligan proposes:
  • ... to set up there a national fertilising farm to be named OMPHALOS with an obelisk hewn and erected after the fashion of Egypt and to offer his dutiful yeoman services for the fecundation of any female of what grade of life soever who should there direct to him with the desire of fulfilling the functions of her natural.
The word also appears in chapter 3, amongst complex imagery of religion, creation and death:
  • One of her sisterhood lugged me squealing into life. Creation from nothing. What has she in the bag? A misbirth with a trailing navelcord, hushed in ruddy wool. The cords of all link back, strandentwining cable of all flesh. That is why mystic monks. Will you be as gods? Gaze in your omphalos.
The first of the Indiana Jones books, Indiana Jones and the Peril at Delphi, features the Omphalos as the MacGuffin. In the novel, the omphalos is described as a small smooth black cone with a knotted net covering its surface. The netting is described as being petrified rather than carved as it is on the actual omphalos at Delphi. When one holds the omphalos they can see into the near and distant future. Whereas in the novel "Dead Sky Black Sun" by Graham McNeill, set in the fantasy world of Warhammer 40,000, the Omphalos Daemonium is a daemon trapped in Chaos armour who captures the heroic Ultramarine Captain, Uriel Ventris, after he becomes caught up in a parallel universe.>>
http://en.wikipedia.org/wiki/Omphaloskepsis wrote:
Omphaloskepsis is the self-absorbed pursuit as an aid to meditation.

From the Greek: omphalos (navel) + skepsis (act of looking, examination), it refers to excessive introspection, self-absorption, or concentration on a single issue. The word has several other forms, such as omphalism used to describe the spiritual practice; omphaloskeptic or omphaloskeptical, for someone who engages in navel-gazing; and omphalocentric meaning to be in a self-absorbed state. Phrases such as "navel-gazers" are common jocular terms for egotism and self-absorbed pursuits. This criticism is also often leveled at professions which are interested in themselves.>>
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by James Wescott » Sat Jan 28, 2012 5:23 am

It takes a lot of energy to make dry ice. Absolute zero is much colder than dry ice. What kind of energy can sustain the massive deep dark invisible cold of the universe?

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Sat Jan 28, 2012 3:03 pm

James Wescott wrote:It takes a lot of energy to make dry ice. Absolute zero is much colder than dry ice. What kind of energy can sustain the massive deep dark invisible cold of the universe?
From a physical sense, it doesn't take energy to make something cold- cold implies the absence of energy. When you make ice, you are expending energy to actively pump heat out of something. That isn't the only way to make ice- no energy is used to sustain Earth's ice caps, for instance- that ice formed because there isn't enough energy available to heat those regions above the freezing point of water. Likewise for the Universe as a whole: most of its volume is cold because there isn't enough energy to warm it.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by neufer » Sat Jan 28, 2012 3:38 pm

Chris Peterson wrote:
Likewise for the Universe as a whole: most of its volume is cold because there isn't enough energy to warm it.
Most of its volume is cold because of expansion caused by:
  • 1) the big bang
    2) inflation
    3) dark energy.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Sat Jan 28, 2012 3:42 pm

neufer wrote:
Chris Peterson wrote:
Likewise for the Universe as a whole: most of its volume is cold because there isn't enough energy to warm it.
Most of its volume is cold because of expansion caused by:
  • 1) the big bang
    2) inflation
    3) dark energy.
Exactly. There isn't enough energy to warm it. <g>
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by neufer » Sat Jan 28, 2012 3:44 pm

Chris Peterson wrote:
neufer wrote:
Chris Peterson wrote:
Likewise for the Universe as a whole: most of its volume is cold because there isn't enough energy to warm it.
Most of its volume is cold because of expansion caused by:
  • 1) the big bang
    2) inflation
    3) dark energy.
Exactly. There isn't enough energy to warm it. <g>
MMMMMmmmm....
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by ErnieM » Wed Aug 22, 2012 3:18 pm

From Wikipedia:
The Wilkinson Microwave Anisotropy Probe (WMAP) – also known as the Microwave Anisotropy Probe (MAP), and Explorer 80 – is a spacecraft which measures differences in the temperature of the Big Bang's remnant radiant heat – the Cosmic Microwave Background Radiation – across the full sky.
I like to get a clarification on the phrase "across the full sky" and how this is accomplished. Is the telescope spinning in parallel to its orbit? How large is the spin, a full spin of 360 degrees or half a spin of 180 degrees? Does this composite reflects a 180 degree or 360 degree orbital image? I am simply trying to reconcile this image with a flat map of the earth split into two side by side ovals pictures.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Wed Aug 22, 2012 3:25 pm

ErnieM wrote:I like to get a clarification on the phrase "across the full sky" and how this is accomplished. Is the telescope spinning in parallel to its orbit? How large is the spin, a full spin of 360 degrees or half a spin of 180 degrees? Does this composite reflects a 180 degree or 360 degree orbital image? I am simply trying to reconcile this image with a flat map of the earth split into two side by side ovals pictures.
WMAP Scan Strategy.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by ErnieM » Fri Aug 24, 2012 11:43 pm

Thank you Chris. Reading this, I now imagine a spherical CMB and we are inside the sphere looking in all directions, hence "all sky map". Then when I clicked at the Pixelization heading, it shows a model of the Earth topography and the CMB radiation temperature anisotropy as surfaces of spheres. If this model is a true representation and that we are looking at the "surface" of a spherical CMB image, does this mean we are seeing the edge of the very young universe?
Conversely, if we are inside the "observable" fast expanding spherical CMB, one must assume the "event horizon or t=0" of the BB is also somewhere inside the CMB and so would Time, when expressed as the radius of the expanding spherical universe.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by bystander » Fri Aug 24, 2012 11:57 pm

ErnieM wrote:Thank you Chris. Reading this, I now imagine a spherical CMB and we are inside the sphere looking in all directions, hence "all sky map". Then when I clicked at the Pixelization heading, it shows a model of the Earth topography and the CMB radiation temperature anisotropy as surfaces of spheres. If this model is a true representation and that we are looking at the "surface" of a spherical CMB image, does this mean we are seeing the edge of the very young universe?
Conversely, if we are inside the "observable" fast expanding spherical CMB, one must assume the "event horizon or t=0" of the BB is also somewhere inside the CMB and so would Time, when expressed as the radius of the expanding spherical universe.
Yes, we are inside the sphere looking out at the edge of our observable universe, but t=0 lies outside that sphere, in all directions.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by ErnieM » Sat Aug 25, 2012 3:03 pm

bystander wrote:
Yes, we are inside the sphere looking out at the edge of our observable universe, but t=0 lies outside that sphere, in all directions.
Are we also to infer that the source of CMBR lies outside the sphere in all directions? How is this possible?

Where is this going to take us? Perhaps to small spheres ("bubbles") joining together forming bigger and "expanding" sphere.

Now this is really a stretch of my imagination to think our expanding universe is the result of and will in the future continue to be joining of smaller Big Bang universes.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Sat Aug 25, 2012 3:29 pm

ErnieM wrote:bystander wrote:
Yes, we are inside the sphere looking out at the edge of our observable universe, but t=0 lies outside that sphere, in all directions.
Are we also to infer that the source of CMBR lies outside the sphere in all directions? How is this possible?
Actually, it is more accurate to consider the surface of the observable universe to be t=0. The moment of the Big Bang does not lie outside the observable Universe, only outside that part which we can observe with electromagnetic radiation. The CMBR is the surface of that sphere, which is slightly smaller than the observable universe. We will be able to see beyond the CMBR, to an even earlier state of the Universe, using gravity waves rather than EM.
Where is this going to take us? Perhaps to small spheres ("bubbles") joining together forming bigger and "expanding" sphere.
There are no bubbles. Every point in the Universe simply has its own observable universe. There's nothing special about any of them... in fact, they don't even have any physical reality. Imagine a bunch of people standing around in a big field at night with lanterns. Each of them has his own observable world, but this has no physical meaning to the entire field at all.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by ErnieM » Sun Aug 26, 2012 10:49 am

Chris wrote:
Actually, it is more accurate to consider the surface of the observable universe to be t=0. The moment of the Big Bang does not lie outside the observable Universe, only outside that part which we can observe with electromagnetic radiation. The CMBR is the surface of that sphere, which is slightly smaller than the observable universe. We will be able to see beyond the CMBR, to an even earlier state of the Universe, using gravity waves rather than EM.

There are no bubbles. Every point in the Universe simply has its own observable universe. There's nothing special about any of them... in fact, they don't even have any physical reality. Imagine a bunch of people standing around in a big field at night with lanterns. Each of them has his own observable world, but this has no physical meaning to the entire field at all.
We are contained within this huge spherical CMBR and existing telescopes limit out capability to see beyond. What lies outside the CMBR, as depicted in this image published by NASA, http://map.gsfc.nasa.gov/media/060915/0 ... line75.jpg , is termed "inflation" from "quantum fluctuations". And this single point of quantum fluctuations gave rise to only one "sphere" that grew and still expanding we call our observed universe. This theory is based on the observed even temperature distribution of the CMBR.

Fast forward to t=now. I put 10 soap bubbles inside a closed box. Some bubbles popped, some joined to form a bigger bubble. You opened the box and there is only one big bubble left. Examining the surface of the big bubble, can we tell how many of the original 10 soap bubbles created it?

What I am trying to describe is the possibility that there were more than one instance of quantum fluctuations, each one producing its own "universe" of difference sizes and shapes. Over billions of years, these "variaverses" gravitated and joined together to form larger and expanding structures. What if the CMB cold spots are remnants of this process?

I suppose we just have to wait and see what the gravitational wave telescopes will reveal.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Sun Aug 26, 2012 3:13 pm

ErnieM wrote:We are contained within this huge spherical CMBR and existing telescopes limit out capability to see beyond. What lies outside the CMBR, as depicted in this image published by NASA, http://map.gsfc.nasa.gov/media/060915/0 ... line75.jpg , is termed "inflation" from "quantum fluctuations". And this single point of quantum fluctuations gave rise to only one "sphere" that grew and still expanding we call our observed universe. This theory is based on the observed even temperature distribution of the CMBR.
You misunderstand the theory. First of all, we are not limited by our telescope technology to seeing beyond the CMBR. The limitation to seeing beyond in EM is fundamental: before this time, the Universe was opaque to photons. No optical telescope will ever be created that can see beyond the CMBR because there is no light coming from beyond.

There is no physical thing "the observable universe". It is as I suggested before with my lantern analogy. If the Universe is a big field, each observer's visible universe is simply the area he can see in the circle of light cast by his lantern. These circles were not created by the Universe.

The Universe is not a sphere; it did not expand spherically from the Big Bang. Observable universes are spherical cross sections of the Universe as a whole. They represent nothing more than the parts of the Universe that an observer can see because they were moving at less than c with respect to that observer when they emitted their photons, gravity waves, or anything else that might be carrying information. The Universe is no different on the outside of the observable universe than it is on the inside. It isn't hotter, or colder, or younger, or older. The Universe is the same everywhere. If you could travel to the edge of the observable universe, you would be no closer to t=0, you wouldn't see anything unusual. You'd be in a new observable universe, of course, with its own CMBR- exactly as far from you there as it is from us here.
Fast forward to t=now. I put 10 soap bubbles inside a closed box. Some bubbles popped, some joined to form a bigger bubble. You opened the box and there is only one big bubble left. Examining the surface of the big bubble, can we tell how many of the original 10 soap bubbles created it?
I think you may be conflating a [very hypothetical] multiverse theory, where different universes were created, of which one is ours, with the idea of the observable universe which is not describable as bubbles, and isn't even a real thing.
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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by BMAONE23 » Sun Aug 26, 2012 3:45 pm

Accordingo the Great and Powerful WIKI...Axium
WIKI wrote:Axium was a Missouri-based band once headed by American Idol season 7 winner David Cook. Their sound was described as Alice in Chains meets Tantric.[1]
According to the Great and Pwerful WIKI...Axiom
WIKI wrote:An axiom is a premise or starting point of reasoning. As classically conceived, an axiom is a premise so evident as to be accepted as true without controversy
In this context I believe Axium was an incorrect spelling for Axiom

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by ErnieM » Tue Aug 28, 2012 6:20 am

Chris wrote:Aug 25
Actually, it is more accurate to consider the surface of the observable universe to be t=0. (1)The moment of the Big Bang does not lie outside the observable Universe, only outside that part which we can observe with electromagnetic radiation.
(2)The CMBR is the surface of that sphere, which is slightly smaller than the observable universe. We will be able to see beyond the CMBR, to an even earlier state of the Universe, using gravity waves rather than EM.
There are no bubbles. Every point in the Universe simply has its own observable universe. There's nothing special about any of them... in fact, they don't even have any physical reality. (3)Imagine a bunch of people standing around in a big field at night with lanterns. Each of them has his own observable world, but this has no physical meaning to the entire field at all
.
No argument. But what if, there were were several big adjacent fields, each separated by tall walls but each adjoining doors. The opening and closing of these doors give different meanings to the adjacent fields.

Chris wrote:Aug 26
You misunderstand the theory. (4)First of all, we are not limited by our telescope technology to seeing beyond the CMBR. The limitation to seeing beyond in EM is fundamental: before this time, the Universe was opaque to photons. No optical telescope will ever be created that can see beyond the CMBR because there is no light coming from beyond.
Beyond the CMBR, space/time has expanded beyond the limits of any man made instruments. Or are we to assume the concept of space/time does not apply beyond the CMBR? Your statements in (2, Augs 25) and (4, Aug 26) appear to be inconsistent.
There is no physical thing "the observable universe". It is as I suggested before with my lantern analogy. (5)If the Universe is a big field, each observer's visible universe is simply the area he can see in the circle of light cast by his lantern. These circles were not created by the Universe.
Your statement is also true of the CMBR. The Universe did not create the CMBR, but for now the CMBR defines the limit of the "observable universe".
(6)The Universe is not a sphere; it did not expand spherically from the Big Bang. (7)Observable universes are spherical cross sections of the Universe as a whole. They represent nothing more than the parts of the Universe that an observer can see because they were moving at less than c with respect to that observer when they emitted their photons, gravity waves, or anything else that might be carrying information.
This appears to be in contradiction to your previous statement (see # 2).
The Universe is no different on the outside of the observable universe than it is on the inside. It isn't hotter, or colder, or younger, or older. The Universe is the same everywhere. If you could travel to the edge of the observable universe, you would be no closer to t=0, you wouldn't see anything unusual. You'd be in a new observable universe, of course, with its own CMBR- exactly as far from you there as it is from us here.
Let me rephrase my original question. Where is time=0 relative to the CMBR and t=now? Is it at, before or after CMBR? Again, I would to refer to your Aug 25 (marked #1).
I think you may be conflating a [very hypothetical] multiverse theory, where different universes were created, of which one is ours, with the idea of the observable universe which is not describable as bubbles, and isn't even a real thing.
Guilty as charge. Further, I am expanding on it and saying that over time, some of these multiverses may have combined (and may be combining now and in the future) similar to how galaxy structures form.

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Re: APOD: The CMB Cold Spot (2011 Mar 21)

Post by Chris Peterson » Tue Aug 28, 2012 2:35 pm

ErnieM wrote:No argument. But what if, there were were several big adjacent fields, each separated by tall walls but each adjoining doors. The opening and closing of these doors give different meanings to the adjacent fields.
Well, you probably know by now that I don't place much weight on "what if" approaches to science if there isn't some sort of evidence behind the suggestion, or a way of testing it.
Beyond the CMBR, space/time has expanded beyond the limits of any man made instruments. Or are we to assume the concept of space/time does not apply beyond the CMBR?
The CMBR does not represent the point where spacetime has expanded beyond the limits of instrumental detection. It only marks the point where we can no longer see using photons. The edge of the observable universe is what marks the limits of detection, and it lies somewhat further than the CMBR.
Your statement is also true of the CMBR. The Universe did not create the CMBR, but for now the CMBR defines the limit of the "observable universe".
As noted, it does not define the edge of the observable universe, but is actually inside that edge. And from the standpoint of the Universe as a whole, there is no observable universe. Observable universes are merely local phenomena that are an inevitable consequence of the expansion of space.
(6)The Universe is not a sphere; it did not expand spherically from the Big Bang. (7)Observable universes are spherical cross sections of the Universe as a whole. They represent nothing more than the parts of the Universe that an observer can see because they were moving at less than c with respect to that observer when they emitted their photons, gravity waves, or anything else that might be carrying information.
This appears to be in contradiction to your previous statement (see # 2).
I see no contradiction. The Universe is not a sphere; it is described by a four-dimensional manifold. Observable universes are three-dimensional, spherical cross sections of the Universe.
Let me rephrase my original question. Where is time=0 relative to the CMBR and t=now? Is it at, before or after CMBR? Again, I would to refer to your Aug 25 (marked #1).
I think I see the point of confusion. The time of the Big Bang (t=0) does not lie anywhere in the 3D universe... it is in the past. The edge of the observable universe defines the surface where any information that reaches us was produced at t=0. It isn't t=0 there now. That surface lies beyond the surface we associate with the source of CMBR photons. Those photons were produced at t=380,000 years, when the Universe became transparent to photons. To see beyond that would require using something other than photons- with gravity waves being the obvious possibility.

Beyond the edge of our observable universe is simply more universe... it is no different there than here. We just can't see it from here.
Chris

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