Another 'far out' cosmology

[owl]

The below was my last post in a 'hijacked' thread about the 'end of space.' In review, I decided to share it on the least respectable section of this forum, "speculations" (and "pseudoscience.")

 

Note: Speculative cosmology is not empirical science. Large scale cosmology beyond our vision (and "before the Bang" speculation) is not verifiable. Not all possible cosmologies are presently empirically observable/verifiable. Yet they may be possible.

 

Replay:

.... I do think the supernova remnant model would be an improvement over the balloon model, though... not like a perfectly spherical shell of a perfectly uniform thickness. And it is an actual explosion of material out into empty space, which is still in the face of the doctrine to the contrary... that that does not happen. (Rather that "space itself expands."... the last word here on what is true and real they say.) Ontologically, what is "space" as such a malleable medium? Who cares?

I refer the forum to my post on that on the last page, post 255. Also a summary yesterday in post 260.

 

One last outrageous possibility, I'd like to share before we are cast to the outer darkness:

I also "like" a multiple bangs/multiple crunches model... that there is "incoming material" that we can't see yet on the way in to "crunch" even as what we see is "outgoing" ... at an accelerating rate of expansion even!

So then we could dump "dark energy" as the anti-gravity factor pushing us ever faster outward... since no one has a clue what "it" might be anyway. The 'stuff further out' from a previous bang would then just be pulling our 'shell' ever faster outward via gravity as we know it. The Cosmic Juggling Act model!

Very speculative, of course... and still without an apology!

[Spyman]

According to Newton's law of universal gravitation your hypothesis of an outer shell pulling us outward via gravity is impossible, the net gravitational forces acting on any body, at any location on the inside, from the bodies surrounding it in an outer shell cancel out.

 

"In classical mechanics, the shell theorem gives gravitational simplifications that can be applied to objects inside or outside a spherically symmetrical body. This theorem has particular application to astronomy.

 

Isaac Newton proved the shell theorem saying that:

 

1. A spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its centre.
   
2. If the body is a spherically symmetric shell (i.e. a hollow ball), no gravitational force is exerted by the shell on any object inside, regardless of the object's location within the shell.
   
3. Inside a solid sphere of constant density the gravitational force varies linearly with distance from the centre, becoming zero at the centre of mass.
   

These results were important to Newton's analysis of planetary motion; they are not immediately obvious, but they can be proven with calculus."

http://en.wikipedia.org/wiki/Shell_theorem

[owl]

What if the multiple bangs sent out matter more like a supernova explosion, i.e., not necessarily into spherical shells per se but more randomly scattered like supernova remnants... kind of a combination of the two cosmologies above?

Then the scattered masses beyond our cosmic event horizon (as far as we can see) might be pulling on what we can see without the spherical gravitational interactions (one sphere inside another), which, I see, would not work.

Then the closer "incoming" mass gets to our visible cosmos, the faster our expansion would accelerate. Of course it could take untold cosmic ages, so we should not expect visible changes anytime soon. Also I would expect to see differences in rate of acceleration in different parts of our sphere of visibility as random clumps of in-coming matter get closer to parts of our cosmos we can see.

 

Thanks for the info. Very interesting.

[Spyman]

No it still won't work because even though individual parts might seem randomly dispersed, momentum is still conserved for the whole explosion making it symmetric in each dimension.

 

"Momentum has the special property that, in a closed system, it is always conserved, even in collisions and separations caused by explosive forces."

http://en.wikipedia.org/wiki/Momentum#Conservation_of_linear_momentum

[owl]

No it still won't work because even though individual parts might seem randomly dispersed, momentum is still conserved for the whole explosion making it symmetric in each dimension.

 

"Momentum has the special property that, in a closed system, it is always conserved, even in collisions and separations caused by explosive forces."

http://en.wikipedia.org/wiki/Momentum#Conservation_of_linear_momentum

Thanks again. But I still have further need of clarification if you have the patience for it.

I understand, I think, what you have presented about the gravitational dynamics of a spherically symmetrical body.

But you seem to have applied single sphere dynamics to multiple (nesting, in my case) shells.

 

According to Newton's law of universal gravitation your hypothesis of an outer shell pulling us outward via gravity is impossible, the net gravitational forces acting on any body, at any location on the inside, from the bodies surrounding it in an outer shell cancel out.

 

Since inner and outer shells must be mutually pulling on each other (as per the universal law of gravitation), what about matter shells from earlier bangs, further out than we can see, (whether or not matter has coalesced into clumps) pulling what we can see ever faster outward?

I'm still struggling with the possibility of mass beyond our vision pulling on mass we can see. Since all mass mutually attracts all other mass, why can't mass beyond our vision be attracting mass we can see on macrocosmic scale. With multiple spherically symmetrical and concentric shells, like a cosmic onion with spaces in between layers, why can't outer shells attract inner shells, as a different case than the dynamics of a single shell as in the info you cited?

I don't yet understand what the "canceling out" of gravitational forces means in this case of multiple shells.

If we focus in just one direction for instance (to simplify it), beyond the farthest galaxies (matter) we can see in a deep probe view, why can't galaxies (matter) beyond that attract visible stuff, pulling it outward faster?

[owl]

I was just reviewing replies and gave second thought to this one from prowler:

Prowler wrote:

Isaac Newton proved the shell theorem saying that:

A spherically symmetric body (effects) external objects gravitationally as though all of its mass were concentrated at a point at its centre.

If a body is a spherically symmetrically shell (i.e., a hollow ball), no gravitational force is exerted by the shell on any object inside, regardless of the object's location within the shell.

Inside a solid sphere of constant density the gravitational force varies linearly with the distance from the centre, becoming zero at the centre of the mass.

The first sentence makes good sense if the spherical body has homogeneous matter density as well as symmetry in its shell. (Not a "given" in the model of an exploding supernova which has a more random distribution of remnants because of differences in original matter density in the explosion... I've studied supernovae as an amateur interest.)

 

The next statement needs revision to make sense. Given a "hollow ball" there are no "objects inside." But I suppose this is to say that gravity is neutral for any object within such a (mostly hollow) shell. Fine. I understand what Spyman cited... for a single 'shell' of matter.

 

No argument with the last statement, a well proven "fact."

 

My argument is that the above does not address the multiple bangs, multiple concentric spheres/shells of matter (of various "thickness".)

Outer shells and inner shells must, as I see it, exert mutual "pull" on each other. This could be the cause or our observable accelerating rate of cosmic expansion.

 

(But I am getting ahead of Spyman's anticipated reply to my last post.) Oh well... I had some extra "time on my hands" for a change. (Not for long!.. a lot of "busy" on the way... not that personal comments are relevant.)

Edited April 14, 2011 by owl

[Spyman]

First off - my name here is "Spyman" and "Prowler" is only my user title, while I think I am alone using it, there are lots of other titles like the "Meson" you have that is used by several persons, so to avoid misunderstandings I think it's best to stick to peoples choosen names.

 

 

Secondly, it was not me saying that, I clearly quoted Wikipedia and gave a link to the source of the quote. You are expressing it as I am the one making that claim as if you want to downplay its credibility but the shell theorem in my quote is well proven beyond doubt in classical mechanics.

 

 

Lastly, my reply to your two presented arguments regarding multiple shells and a simplified view in one direction:

 

It doesn't matter how many shells there are, you can still make an arbitrary choice between any two adjacent shells and from that layer declare all inner shells as one "center point" and all other shells as one "hollow ball". According to Newton's law of gravity the "center point" would be gravitationally pulling in on the surrounding walls of the "hollow ball" but the walls themselves is unable to affect any bodies on their inside.

 

When the shells are gravitationally symmetric, in roughly spherical shapes and with distinct borders where the inside boundary of larger shells completely encapsules all smaller shells, there is no net gravitational force exerted from any of the outer shells on any of the inner shells.

 

Adding more smaller shells on the inside doesn't change anything else than increasing mass at the center point.

 

Adding more larger shells on the outside doesn't change anything at all, since they will all be unable to affect anything on their own inside.

 

 

The shell theorem shows that a simplified view in one direction does not work in a full three dimensional reality.

 

If you want to model a world with three spatial dimensions then you need to fully account for all of them.

Edited April 15, 2011 by Spyman

[owl]

Sorry about the name and quote mix up. Obvious in retrospect.

 

Seems to violate the universal law of gravitation to claim that stuff further out than we can see is not pulling outward on stuff we can see... since all matter attracts all other matter, the closer the more attractive force...

Must be that the pull of the closer stuff is balanced my the way more mass of the farther stuff in the rest of the total mass of all shells.

 

Thanks anyway. I'll leave it.

[md65536]

Seems to violate the universal law of gravitation to claim that stuff further out than we can see is not pulling outward on stuff we can see... since all matter attracts all other matter, the closer the more attractive force...

Must be that the pull of the closer stuff is balanced my the way more mass of the farther stuff in the rest of the total mass of all shells.

Well not really...

 

The stuff that is "farther than we can see" is so not because it's too dim or anything, but because of causality: Light, gravity etc from this potential stuff can't reach us in time for us to know that it's there. No information about this stuff reaches us.

 

If there is stuff "in between" what we can see and what we can't see, AND if that stuff can be affected by things that we can't see, that means that observations that can't reach us in time, can reach the in-between stuff and affect it. BUT, if we can make observations of this in-between stuff, that means that light from it has time to reach us.

 

So if this "in between" stuff is pulled by gravity due to something unknown, and we make an observation of that in-between stuff being pulled by gravity, it is only due to our being able to observe the in-between stuff, which means light has had time to get here from there. But then, light, gravity etc from the unknown stuff would also have the time to make it here (since an observation of it would arrive at the same time as an observation of the "stuff" being affected by it).

 

Stuff that's too far away to affect us causally, is too far away to affect causally anything that we can observe being affected.

 

 

 

 

Or in other words... if we couldn't see the far unknown junk due to causality, but some in-between stuff was being pulled by its gravity, we wouldn't know that it was being pulled until at least the time that the unknown junk became causally observable. We could not see evidence of the unknown stuff, until it is observable.

Edited April 15, 2011 by md65536

[owl]

md65536,

Huh? What "in between stuff?" As far as we can see (present tense) is our cosmic event horizon. Beyond that is anybody's guess. I was guessing that stuff which is further out than we can see could be pulling outward on our visible cosmos, as we observe its expanding at an accelerating rate, and nobody knows why. Positing some sort of anti-gravity mystery matter or "dark energy" is not an answer, just making up words for "some mysterious unknown force." Spyman tells me that the pull of "far out" stuff can not account for this visible expansion.

Seems like you are playing in a different ballpark.

[md65536]

md65536,

Huh? What "in between stuff?" As far as we can see (present tense) is our cosmic event horizon. Beyond that is anybody's guess. I was guessing that stuff which is further out than we can see could be pulling outward on our visible cosmos, as we observe its expanding at an accelerating rate, and nobody knows why. Positing some sort of anti-gravity mystery matter or "dark energy" is not an answer, just making up words for "some mysterious unknown force." Spyman tells me that the pull of "far out" stuff can not account for this visible expansion.

Seems like you are playing in a different ballpark.

I might be talking about something else, but I think it applies here. The "in between stuff" would be "stuff that is visible to us" that might be pulled by farther away stuff that is beyond our "cosmic event horizon." I explained it poorly, but I'll try to say it again hopefully simpler to see if it adds anything useful:

 

We cannot observe anything within our cosmic event horizon being affected by anything outside of our cosmic event horizon, because the time that it takes for such observations to reach us, would allow the effects of that "outside" thing to reach us. If we have any evidence of its effects, then it is within our cosmic event horizon.

 

If we see something at the edge of the universe being pulled "outward" by a gravitational force, then we should also be affected (to a much smaller degree due to the huge increase in distance) by the same gravitational force.

 

 

 

Seems to violate the universal law of gravitation to claim that stuff further out than we can see is not pulling outward on stuff we can see... since all matter attracts all other matter, the closer the more attractive force...

This is where we're clashing. There is no such law, because it contradicts the law of causality. According to causality, if you separate 2 things by some great distance (say by inflation), they cannot begin to gravitationally attract each other sooner than it takes light (in a vacuum) to travel the distance between them. Universal gravitation would be restricted by the theoretical speed of gravity waves, which is c.

Edited April 16, 2011 by md65536

[Iggy]

md65536,

Huh? What "in between stuff?" As far as we can see (present tense) is our cosmic event horizon. Beyond that is anybody's guess. I was guessing that stuff which is further out than we can see could be pulling outward on our visible cosmos, as we observe its expanding at an accelerating rate, and nobody knows why. Positing some sort of anti-gravity mystery matter or "dark energy" is not an answer, just making up words for "some mysterious unknown force." Spyman tells me that the pull of "far out" stuff can not account for this visible expansion.

Seems like you are playing in a different ballpark.

 

I might be talking about something else, but I think it applies here. The "in between stuff" would be "stuff that is visible to us" that might be pulled by farther away stuff that is beyond our "cosmic event horizon." I explained it poorly, but I'll try to say it again hopefully simpler to see if it adds anything useful:

 

We cannot observe anything within our cosmic event horizon being affected by anything outside of our cosmic event horizon, because the time that it takes for such observations to reach us, would allow the effects of that "outside" thing to reach us.

 

That makes sense to me. If it is outside our past light cone then we won't see its effects.

 

I also agree with Spyman about Newton's shell theorem. As massive as the universe out there is, it doesn't pull stuff up off of planet earth. Gravity doesn't work that way. Outer shells don't pull inner shells up.

 

Also, Owl's explanation would have earth be at the center of the universe -- that the universe be like an onion with earth at its center. Not likely.

[Spyman]

Must be that the pull of the closer stuff is balanced my the way more mass of the farther stuff in the rest of the total mass of all shells.

Yes, thats is correct. Individual objects in a surrounding shell does of course interact gravitationally with objects on the inside. What Newton proved is that if the shell is symmetric then when considering the whole shell, the sum of forces from all objects it consists of cancel out for inside objects. When the inside object moves closer towards the shell, it will also get less of the shell ahead and more of the shell behind it.

Edited April 16, 2011 by Spyman

[michel123456]

Well not really...

 

The stuff that is "farther than we can see" is so not because it's too dim or anything, but because of causality: Light, gravity etc from this potential stuff can't reach us in time for us to know that it's there. No information about this stuff reaches us.

 

If there is stuff "in between" what we can see and what we can't see, AND if that stuff can be affected by things that we can't see, that means that observations that can't reach us in time, can reach the in-between stuff and affect it. BUT, if we can make observations of this in-between stuff, that means that light from it has time to reach us.

 

So if this "in between" stuff is pulled by gravity due to something unknown, and we make an observation of that in-between stuff being pulled by gravity, it is only due to our being able to observe the in-between stuff, which means light has had time to get here from there. But then, light, gravity etc from the unknown stuff would also have the time to make it here (since an observation of it would arrive at the same time as an observation of the "stuff" being affected by it).

 

Stuff that's too far away to affect us causally, is too far away to affect causally anything that we can observe being affected.

 

 

 

 

Or in other words... if we couldn't see the far unknown junk due to causality, but some in-between stuff was being pulled by its gravity, we wouldn't know that it was being pulled until at least the time that the unknown junk became causally observable. We could not see evidence of the unknown stuff, until it is observable.

 

I think you are driving conclusions too quickly.

Put all that in a diagram.

Edited April 16, 2011 by michel123456

[Spyman]

We cannot observe anything within our cosmic event horizon being affected by anything outside of our cosmic event horizon, because the time that it takes for such observations to reach us, would allow the effects of that "outside" thing to reach us. If we have any evidence of its effects, then it is within our cosmic event horizon.

You might find it interesting to know that there might have been something huge and very dense inside our past light cone in early times, while it is now outside so we are unable to observe it, we are still able to observe its effects on our surroundings.

 

The discovery of a Dark Flow is still highly controversial and could likely turn out to be false but can also end up getting confirmed.

 

My understanding is that before the Recombination the Universe was to "foggy" to let light traverse, but since gravity is not limited by such restrictions our part of the Universe could have been affected by a surrounding neighborhood that moved beyond our cosmic horizon before the Recombination. As such we are not able to view this neighborhood but we can observe the imprint its gravity left behind.

 

Mysterious New 'Dark Flow' Discovered in Space

As if the mysteries of dark matter and dark energy weren't vexing enough, another baffling cosmic puzzle has been discovered.

 

Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can't be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon "dark flow."

 

The stuff that's pulling this matter must be outside the observable universe, researchers conclude.

http://www.space.com/5878-mysterious-dark-flow-discovered-space.html

 

 

Dark flow is a term from astrophysics describing a peculiar velocity of galaxy clusters. The actual measured velocity is the sum of the velocity predicted by Hubble's Law plus a small and unexplained (or dark) velocity flowing in a common direction.

 

According to standard cosmological models, the motion of galaxy clusters with respect to the cosmic microwave background should be randomly distributed in all directions. However, analyzing the three-year WMAP data using the kinematic Sunyaev-Zel'dovich effect, the authors of the study found evidence of a "surprisingly coherent" 600–1000 km/s flow of clusters toward a 20-degree patch of sky between the constellations of Centaurus and Vela.

 

The authors (Alexander Kashlinsky, F. Atrio-Barandela, D. Kocevski, and H. Ebeling) suggest that the motion may be a remnant of the influence of no-longer-visible regions of the universe prior to inflation. Telescopes cannot see events earlier than about 380,000 years after the big bang, when the universe became transparent (the Cosmic Microwave Background); this corresponds to the particle horizon at a distance of about 46 billion (4.6×10¹⁰) light years. Since the matter causing the net motion in this proposal is outside this range, it would in a certain sense be outside our visible universe; however, it would still be in our past light cone.

http://en.wikipedia.org/wiki/Dark_flow

[md65536]

You might find it interesting to know that there might have been something huge and very dense inside our past light cone in early times, while it is now outside so we are unable to observe it, we are still able to observe its effects on our surroundings.

Yes, that's interesting and I hadn't thought of it. This is now certainly beyond my knowledge.

 

 

However I think I'm still technically right...

 

If something was previously inside our light cone but was moved out (or otherwise disappeared), we may still observe that object but only as it was while it was inside our light cone.

If we observe another object being affected by it, we observe it being affected by it only as it was while it was still inside our light cone.

 

Once an object is moved outside our light cone, we cannot make any observation of that object in a state after it was moved outside, nor of any effect of that object in a state after it was moved, that was made on our surroundings (whether near or distant).

 

 

I guess it depends on whether you equate "something" with "the same thing in a past state."

 

It's true that no effect of the past state of something can be observed if its past state is outside our light cone.

It's true that no effect of the current state of something can be observed if it is currently outside our light cone.

It's NOT true (as you pointed out) that no effect of the past state of something can be observed if it is currently outside our light cone.

 

We cannot observe anything within our cosmic event horizon being affected by anything outside of our cosmic event horizon,

 

I think that's still correct because if we see an effect of something, we're talking about that something as it was while it was inside our light cone, not about an effect of that something as it was later (when it may have been moved outside the light cone).

Edited April 16, 2011 by md65536

[Spyman]

However I think I'm still technically right...

Yes, sorry, maybe I should have mentioned that, I never meant to argue, only thought you would find Dark Flow interesting in the context.

[michel123456]

You might find it interesting to know that there might have been something huge and very dense inside our past light cone in early times, while it is now outside so we are unable to observe it, we are still able to observe its effects on our surroundings.

 

 

 

 

I am glad that you say that.

 

You must know that I am a supporter of that principle.

Not to mention that IMHO this "something huge and very dense inside our past light cone" can still be there, if one can say that talking about the past. i have had turbulent discussions on this Forum about the interpretation of a spacetime diagram. I am still convinced that there is plenty of room for unobservable matter in our past cone.

 

The discovery of a Dark Flow is still highly controversial and could likely turn out to be false but can also end up getting confirmed.

 

The Dark Flow is very interesting, but very speculative too.

Edited April 16, 2011 by michel123456

[owl]

Iggy:

That makes sense to me. If it is outside our past light cone then we won't see its effects.

 

Even without introducing time as a thing (search "presentism") as in the light cone example , we can stay on the same page by just stating the obvious: We can't see what is beyond our sphere of visibility, which of course is limited by lightspeed of far away images (very old light) and the speed of those light sources in outward cosmic expansion.

(I wonder how special relativity deals with this trade off. Just an aside.)

Iggy, cont'd:

I also agree with Spyman about Newton's shell theorem. As massive as the universe out there is, it doesn't pull stuff up off of planet earth. Gravity doesn't work that way. Outer shells don't pull inner shells up.

 

Yet, stuff, say in clumps, maybe having coalesced from a previous bang, could still be the gravitational cause of some areas of the visible cosmos "speeding up" relative to the general rate of expansion as in Spyman's cited anomaly.*

Iggy:

Also, Owl's explanation would have earth be at the center of the universe -- that the universe be like an onion with earth at its center. Not likely.

 

One would be a stupid fool to believe the earth to be the center of the universe, as I explained in detail in the cosmology discussion as it was still in the old thread about the end of space. I will find my piece on the above if you want. You either didn't read it or just enjoy casting me as above. I had earth and our visible cosmos deep in the membrane thickness of a way larger scale "balloon" model in that context.

 

* To Spyman's piece as above:

Mysterious New 'Dark Flow' Discovered in Space

As if the mysteries of dark matter and dark energy weren't vexing enough, another baffling cosmic puzzle has been discovered.

 

Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can't be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon "dark flow."

 

The stuff that's pulling this matter must be outside the observable universe, researchers conclude.

http://www.space.com...ered-space.html

 

So, back to possible clumps of matter (say combined supermassive black holes) beyond our vision attracting these "patches" faster than their surroundings. My supernovae model was an intentional departure from symmetrical shells of homogeneous density and thickness. (Not a homogenous distribution of denser matter, gasses, dust, etc.) As a small scale model, given multiple bangs, not just one big one, why could that model not still be viable? The symmetry of the explosion may be an arguable point, requiring adjustment of the model. But if there has been a series of bangs, that could account for whatever "far out" stuff we can't see and a lack of symmetry as "incoming" and "out going" mix it up as an overall dynamic. Very speculative, of course... which is why it is presented in this section.

 

BTW: Who says that gravity is not a constant force ever since the bang or bangs, just diminished in force with more distance (the square of the distance, as I understand it) ad infinitum. There is no waiting while "gravity waves" reach us, as argued above. For example, the gravitational pull between earth (and other planets) and the sun is steady. No delays waiting for it to reach us just because it travels at light speed, if it does...which seems well established.

Edited April 16, 2011 by owl

[Spyman]

So, back to possible clumps of matter (say combined supermassive black holes) beyond our vision attracting these "patches" faster than their surroundings. My supernovae model was an intentional departure from symmetrical shells of homogeneous density and thickness. (Not a homogenous distribution of denser matter, gasses, dust, etc.) As a small scale model, given multiple bangs, not just one big one, why could that model not still be viable? The symmetry of the explosion may be an arguable point, requiring adjustment of the model. But if there has been a series of bangs, that could account for whatever "far out" stuff we can't see and a lack of symmetry as "incoming" and "out going" mix it up as an overall dynamic. Very speculative, of course... which is why it is presented in this section.

If you are abandoning the symmetrical shell that normally would be the remnant of an explosion in vacuum then I think your model need to explain how that is possible and how the remnant is shaped.

 

For a supernova explosion the outer shell is closely spherical and gravitationally symmetric, which therefore means it is not able to by gravity affect anything inside it.

 

More dense areas inside our membrane could be able to pull us sideways and if the outer shell is "incoming" such that it already have collided with our shell and have certain parts already inside our membrane, then those could also interact gravitationally and pull us sideways.

 

But as already proved: explosions are gravitationally symmetrical and outer shells are not able to pull us outward.

 

Thus your model is not able to explain the observed acceleration of expansion.

 

You need to accknowledge this before we can continue and look at other problems with your model.

 

 

BTW: Who says that gravity is not a constant force ever since the bang or bangs, just diminished in force with more distance (the square of the distance, as I understand it) ad infinitum. There is no waiting while "gravity waves" reach us, as argued above. For example, the gravitational pull between earth (and other planets) and the sun is steady. No delays waiting for it to reach us just because it travels at light speed, if it does...which seems well established.

Gravity is predicted by Relativity to propegate with lightspeed but AFAIK not yet directly confirmed by measurements.

(Altought there is indirect observational evidence for gravitational waves.)

 

IMHO derailing the thread into Relativity or arguments concerning the speed of gravity will likely ruin the discussion of your model.

Edited April 18, 2011 by Spyman

[Iggy]

You might find it interesting to know that there might have been something huge and very dense inside our past light cone in early times, while it is now outside so we are unable to observe it, we are still able to observe its effects on our surroundings.

 

The discovery of a Dark Flow is still highly controversial and could likely turn out to be false but can also end up getting confirmed.

 

My understanding is that before the Recombination the Universe was to "foggy" to let light traverse, but since gravity is not limited by such restrictions our part of the Universe could have been affected by a surrounding neighborhood that moved beyond our cosmic horizon before the Recombination. As such we are not able to view this neighborhood but we can observe the imprint its gravity left behind.

 

That is my understanding as well. As a remnant of inflation, the universe was opaque when it crossed our past light cone which puts it inside our past light cone but outside our "visible universe" (the visible universe stopping at the cosmic microwave background).

 

One would be a stupid fool to believe the earth to be the center of the universe, as I explained in detail in the cosmology discussion as it was still in the old thread about the end of space. I will find my piece on the above if you want. You either didn't read it or just enjoy casting me as above. I had earth and our visible cosmos deep in the membrane thickness of a way larger scale "balloon" model in that context.

 

Do you think expansion is accelerating in just one direction of the sky, or in every direction equally?

The increased density that you are dreaming up, do you think it is in just one direction of the sky, or in every direction equally?

 

If the answer to both questions is "every direction equally" then earth is by extension at the center.

[owl]

If you are abandoning the symmetrical shell that normally would be the remnant of an explosion in vacuum then I think your model need to explain how that is possible and how the remnant is shaped.

 

For a supernova explosion the outer shell is closely spherical and gravitationally symmetric, which therefore means it is not able to by gravity affect anything inside it.

 

More dense areas inside our membrane could be able to pull us sideways and if the outer shell is "incoming" such that it already have collided with our shell and have certain parts already inside our membrane, then those could also interact gravitationally and pull us sideways.

 

But as already proved: explosions are gravitationally symmetrical and outer shells are not able to pull us outward.

 

Thus your model is not able to explain the observed acceleration of expansion.

 

My multiple bangs and crunches model has matter of multiple bangs out beyond our sphere of visibility, not necessarily still in spherical symmetrical shells (as originally from the bang/bangs) but having coalesced into clumps or combined supermassive black holes... some possibly still expanding outward, some possibly having reversed and now imploding and perhaps interacting with our visible cosmos, like those speeding up anomalous patches you cited above (just in spots closest to incoming clumps of matter.)

So the overall shape would be the cosmos as we see it expanding in all directions outward with possible scattered clumps beyond or cosmic horizon pulling parts of what we see outward faster than surrounding areas. (Maybe repetitive, but hopefully a clarification.) I'm not clear on how randomly distributed such "clumps" must be to be no longer considered a symmetrical outer shell or shells and still have a pulling-outward effect on what we can see (no longer as symmetrical shells within shells.)

You need to acknowledge this before we can continue and look at other problems with your model.

 

Maybe the above gets around the gravitational zero sum situation/limitation of nesting spheres.

 

 

Gravity is predicted by Relativity to propegate with lightspeed but AFAIK not yet directly confirmed by measurements.

(Altought there is indirect observational evidence for gravitational waves.)

 

IMHO derailing the thread into Relativity or arguments concerning the speed of gravity will likely ruin the discussion of your model.

 

My comments about gravity being a steady pull on all matter since the bang(s) was an argument against the above posts positing limitations on gravity's range and a precluding lime lag before its visible effects from "beyond" could reach and effect what we can see. Obviously there are no gaps in gravitational force between sun and earth (it is steady) even though it would take eight minutes for earth to start flying off tangent to its orbit if the sun ceased to exist.

Hope this clarifies the finer points of this (again) very speculative cosmology.

 

Iggy:

Do you think expansion is accelerating in just one direction of the sky, or in every direction equally?

The increased density that you are dreaming up, do you think it is in just one direction of the sky, or in every direction equally?

 

If the answer to both questions is "every direction equally" then earth is by extension at the center.

See Spyman's anomaly above where some patches are accelerating outward faster than the norm. Everything is moving away from everything else at an accelerating rate of expansion, and it all looks isotropic and homogeneous from here. This does not, of course, demand that earth is the center of the expanding cosmos... the cosmic equivalent of the pre-Copernican view of sun orbiting earth and earth being the center of the universe.

Edited April 18, 2011 by owl

[Iggy]

Iggy:

Do you think expansion is accelerating in just one direction of the sky, or in every direction equally?

The increased density that you are dreaming up, do you think it is in just one direction of the sky, or in every direction equally?

 

If the answer to both questions is "every direction equally" then earth is by extension at the center.

See Spyman's anomaly above where some patches are accelerating outward faster than the norm. Everything is moving away from everything else at an accelerating rate of expansion, and it all looks isotropic and homogeneous from here. This does not, of course, demand that earth is the center of the expanding cosmos... the cosmic equivalent of the pre-Copernican view of sun orbiting earth and earth being the center of the universe.

 

It might be helpful to mention... rather than putting

around a quote of someone's post, or part of their post --you can hit "reply" under their post and use the opening quote tag that will be there. It looks like

so that instead of using

you would use something that looks like

. That would help other people because it puts a link on the quote block that takes people to the post that is being quoted and the date and time it was written.

 

Your response answered my first question, but not my second. But, I won't push it. It would be too difficult to explain why your postulates, as flawed as they are, do not imply the conclusion that you assume they imply unless earth were at the center of the shell.

 

I apparently can't even explain why a sphere representing the visible universe embedded in the rubber skin of a balloon never expands with isotropy no matter what size the sphere is relative to the skin of the balloon, yet the visible universe does expand with isotropy so it is a failed model.

 

If the words don't make sense to you, then they don't make sense.

[owl]

Iggy:

... It would be too difficult to explain why your postulates, as flawed as they are, do not imply the conclusion that you assume they imply unless earth were at the center of the shell.

 

Translation: 'You are wrong as usual, but it is just too much trouble to explain why.'

The big mystery to me is, after our history of near perfect miscommunication, why do you continue to reply to my posts?

Iggy:

I apparently can't even explain why a sphere representing the visible universe embedded in the rubber skin of a balloon never expands with isotropy no matter what size the sphere is relative to the skin of the balloon, yet the visible universe does expand with isotropy so it is a failed model.

 

What you never understood about that model was the scale of the whole expanding balloon with a thick skin and buried deep within that skin is the "atom" of our solar system (part of a molecule/ galaxy of "rubber".)

Also you missed the hologram reference... that the "minutia" of each little sphere of visibility within the membrane is expanding on very small scale relative to the whole balloon, which is also expanding. (As with the minutia, so with the whole.)

But now I am presenting a multiple bangs scenario, which you also fail to grasp. Stuff that was "launched" way earlier than the "present bang" could easily have had time to coalesce into clumps, pulling each other out of their original symmetry, i.e., no longer a nice symmetrical sphere containing our visible sphere. My last post was an attempt to clarify that and ask how "clumpy" the far out stuff must be to no longer be considered a symmetrical sphere 'containing' our visible sphere.

 

I no case is the earth the center of the cosmos... quite obviously.

 

My sense is that all of the above makes no sense to you, so you "fail" my models (in last thread and here) without understanding them. I gave up hope of communication with you long ago, and that has not changed.

[Iggy]

The big mystery to me is, after our history of near perfect miscommunication, why do you continue to reply to my posts?

 

If you find my first post in this thread you'll see I wasn't responding to you or talking to you.

 

What you never understood about that model was the scale of the whole expanding balloon with a thick skin and buried deep within that skin is the "atom" of our solar system (part of a molecule/ galaxy of "rubber".)

 

What you don't understand is that the scale is irrelevant.

 

At no scale or size does a 3D sphere drawn inside the skin of a balloon expand in an isotropic way when the balloon is inflated. It is either so small, like an atom, that it doesn't expand at all or it is large enough that it expands in one direction and constricts in the other. In neither case does the sphere represent the expanding visible universe which does expand in an isotropic way.

 

The analogy is flawed at the most basic level.