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Posted
How so? A photon's wavelength does not change in transit, rather the Hubble redshift is due to our recession velocity from the photon's source.

Yes that is the redshift effect, but photons from the CMB for example started of at at wavelength corresponding to 3000K and cooled down to 2.73K due to expansion of space,primarily at least.

Posted

An expansion will increase entropy. While an increase in entropy can occur if it can absorb energy. For example, if we expand a gas, the gas will get colder because the increase in entropy absorbs energy. I can see the CMB and loss of energy from 3000K being the fuel for higher entropy, with the entropy increase causing the red shift as it absorbs energy value from this energy. One can do this in the lab, using IR and a canister of gas, causing a red shift in the IR, as the canister cools and entropy absorbs heat.

 

Because the energy remaining in the CMB is close to absolute zero, there is less energy for entropy from that source. So there needs to be other sources of energy to account for the entropy of further expansion. One possible source is nuclear fusion and the loss of entropy due to galaxy formation. That could explain the entropy increase of the universe, relative to the galaxies but not within the galaxies. While simply increasing the number of fusing stars and the order and superorder within galaxies over time, could explain the energy source for the increasing entropy of an accelerated expansion.

 

This does not preclude dark matter or dark energy. If dark matter is forming matter it has to lower entropy to merge into something less elusive and more tangible. This would also give off energy for additional entropy but for elsewhere. We can also toss in the CMB for energy, with that level of energy, only useful for subtle entropy, such as rotating and vibrating water molecules.

 

Expanding space-time, via GR, is just a special case of entropy increasing but not the whole story, since it doesn't take into account all the entropy details with any frame of reference. If we form a star from gas cloud, and contract space-time, the entropy lowers as the pressure of the contraction reduces the space between matter. It is not just space-time contracting with everything maintaining relative distances, but the actual distances between things are lowering with system entropy decreasing.

 

With SR everything does not fuse, like a star, due to actual distance changes, but rather relative distances are maintained in the reference. The entropy within SR is connected to velocity and the entropy created relative to the observer. If it is heading toward us, the entropy is lowering for the observer-source system, giving off energy, for a blue shift. If it is moving away, it is increasing entropy for the observer-source system and will absorb energy and red shift. The universe is working in terms of net effects, with entropy increasing, absorbing energy.

 

If we started with a singularity, it has zero entropy or minimum entropy. It has to absorb energy to increase entropy to become something other than a singularity. This creates an interesting question. Does entropy have a push of its own absorbing energy, or does energy push entropy? If entropy walks to the beat of its own drum, there needs to be a potential to create disorder, so it can absorb energy. This sort of implies empty space outside the singularity. As space fills and the energy lowers we will need other sources to meet the entropy demand for energy. If energy is pushing entropy, it doesn't matter what the space around is, it can be contracted, as long as energy is pushing it.

Posted

G'day from the land of ozzzzz

 

We see by observations, matter going towards the cenre of a galaxy and we observe the ejection of matter via jets that are able to reform and feedack matter in the process of galactic evolution.

 

This paper is quite interesting along those lines.

 

[0906.1789] Non-singular cosmology in a model of non-relativistic gravity

Non-singular cosmology in a model of non-relativistic gravity

 

Authors: Yi-Fu Cai, Emmanuel N. Saridakis

(Submitted on 9 Jun 2009)

 

Abstract: We present a model of non-relativistic gravitational theory which is power-counting renormalizable in 3+1 dimensional spacetime. When applied to cosmology, the relativity-violation terms lead to a dark radiation component, which can give rise to a bounce if dark radiation possesses negative energy density. Additionally, we investigate a cyclic extension of the non-singular cosmology in which the universe undergoes contractions and expansions periodically. In both scenarios the background theory is well defined at the quantum level.
Posted

Pluto:

If by definition the universe is all.

 

Where does space expand into?

 

How can space without matter expand?

 

What does the expansion?

 

I can not imagine what an end or boundary to space might be or what then would lie beyond such a boundary. If anyone here can clarify this I would very much appreciate it. And certainly we must distinguish between the "stuff in space" and whatever we want to call the volume which "it all" exists *in.*

 

So you are saying that space does not expand.

 

Matter expands in space.

 

That's what I have always said/challenged... until everyone was tired of hearing it. What is it exactly that is supposed to be expanding besides the increasing distances between objects moving in outward trajectory from the "Bang" and apart from each other?

Michael

Posted

G'day Michael

 

The BBT states that it Banged everywhere from so called singularity points at the same time. So you would see expansion from those points.

 

Thats the evidence that I'm trying to find.

 

But! they tell us that everything is moving away from us.

 

Us being Earth.

 

Thats the funny thing. Why Earth?

 

Tells me there is a common error in data. Asking for a better understanding.

 

To look at it in perpective, see this link

 

Planet and Star Size Comparison (music Yann Tiersen) http://video.google.com/videoplay?docid=-4495546151448213121

Posted

Pluto,

If you look at my model in "Bang/Crunch Revisited" you will see a model of galaxies all expanding away from each other (as we see), isotropic in all directions (as we see) and a metaphor of galaxies being molecules of rubber (and stars as atoms, I would add) within the rubber membrane of a mega-cosmos... which we can not see... as our cosmic event horizon is buried deep within the thickness of the expanding (and thinning) rubber.

The elasticity of the rubber balloon is analogous to the force of gravity, as all masses pull on all other masses eventually to overcome and reverse the outward force of the "bang"... whatever its dynamic and scale... Cyclical cosmi as micro-spheres within the macro-cosmic balloon rubber... to the whole balloon finally ceasing to expand and then 'deflating' back into a primordial mass of "Rubber" ... which then "goes bang" again.

 

This makes way more sense to me than the popular M-theory cosmology... which has, I think, much more imaginative fantasy in it than the above.

 

I'm glad you are here.

(Please send me a PM on how you got to be a "notorious" bad boy like me on this site... and who does the judgmental labels, if you know.)

Michael

Posted
The BBT states that it Banged everywhere from so called singularity points at the same time. So you would see expansion from those points.

 

BBT says no such thing.

 

You've read that the big bang didn't happen at one place in space, but happened 'everywhere'. You've incorrectly interpreted this as "singularity points" everywhere in space all exploding stuff simultaneously. This is not what big bang theory claims, as people have previously indicated to you.

 

There was only one 'singularity' just as there's only one universe. Nothing left the singularity. Nothing exploded out of a singularity. The singularity was the universe and it expanded. We are still in it—still expanding. "Expanding" means that astronomical objects over large cosmic distances are all moving away from everything else.

The Big Bang is not an explosion of matter moving outward to fill an empty universe. Instead, space itself expands with time everywhere and increases the physical distance between two comoving points.

 

 

Do you have a source backing up your claim characterizing multiple singularity points throughout space?

 

~modest

Posted

G'day from the land of ozzzzzzz

 

Modest your opinion is wrong or your right and NASA is wrong.

 

To begin with I do not agree with the BIG Bang.

 

Regardless here are some papers on the Big Bang Theory

 

Evidence for the Big Bang

Evidence for the Big Bang

 

 

1) What is the Big Bang theory?

a) Common misconceptions about the Big Bang

In most popularized science sources, BBT is often described with something like "The universe came into being due to the explosion of a point in which all matter was concentrated." Not surprisingly, this is probably the standard impression which most people have of the theory. Occasionally, one even hears "In the beginning, there was nothing, which exploded."

 

There are several misconceptions hidden in these statements:

 

•The BBT is not about the origin of the universe. Rather, its primary focus is the development of the universe over time.

•BBT does not imply that the universe was ever point-like.

•The origin of the universe was not an explosion of matter into already existing space.

The famous cosmologist P. J. E. Peebles stated this succinctly in the January 2001 edition of Scientific American (the whole issue was about cosmology and is worth reading!): "That the universe is expanding and cooling is the essence of the big bang theory. You will notice I have said nothing about an 'explosion' - the big bang theory describes how our universe is evolving, not how it began." (p. 44). The March 2005 issue also contained an excellent article pointing out and correcting many of the usual misconceptions about BBT.

 

Another cosmologist, the German Rudolf Kippenhahn, wrote the following in his book "Kosmologie fuer die Westentasche" ("cosmology for the pocket"): "There is also the widespread mistaken belief that, according to Hubble's law, the Big Bang began at one certain point in space. For example: At one point, an explosion happened, and from that an explosion cloud travelled into empty space, like an explosion on earth, and the matter in it thins out into greater areas of space more and more. No, Hubble's law only says that matter was more dense everywhere at an earlier time, and that it thins out over time because everything flows away from each other." In a footnote, he added: "In popular science presentations, often early phases of the universe are mentioned as 'at the time when the universe was as big as an apple' or 'as a pea'. What is meant there is in general the epoch in which not the whole, but only the part of the universe which is observable today had these sizes." (pp. 46, 47; FAQ author's translation, all emphasizes in original)

 

Finally, the webpage describing the ekpyrotic universe (a model for the early universe involving concepts from string theory) contains a good recounting of the standard misconceptions. Read the first paragraph, "What is the Big Bang model?".

 

There are a number of reasons that these misconceptions persist in the public mind. First and foremost, the term "Big Bang" was originally coined in 1950 by Sir Fred Hoyle, a staunch opponent of the theory. He was a proponent of the competing "Steady State" model and had a very low opinion of the idea of an expanding universe. Another source of confusion is the oft repeated expression "primeval atom". This was used by Lemaitre (one of the theory's early developers) in 1927 to explain the concept to a lay audience, albeit one that would not be familiar with the idea of nuclear bombs for a few decades to come. With these and other misleading descriptions endlessly propagated by otherwise well-meaning (and not so well-meaning) media figures, it is not surprising that many people have wildly distorted ideas about what BBT says. Likewise, the fact that many in the public think the theory is rather ridiculous is to be expected, given their inaccurate understanding of the theory and the data behind it.

 

 

 

But!!

 

 

THE BIG BANG:

THE BIG BANG

 

About 15 billion years ago a tremendous explosion started the expansion of the universe. This explosion is known as the Big Bang. At the point of this event all of the matter and energy of space was contained at one point. What exisisted prior to this event is completely unknown and is a matter of pure speculation. This occurance was not a conventional explosion but rather an event filling all of space with all of the particles of the embryonic universe rushing away from each other. The Big Bang actually consisted of an explosion of space within itself unlike an explosion of a bomb were fragments are thrown outward. The galaxies were not all clumped together, but rather the Big Bang lay the foundations for the universe.

 

The origin of the Big Bang theory can be credited to Edwin Hubble. Hubble made the observation that the universe is continuously expanding. He discovered that a galaxys velocity is proportional to its distance. Galaxies that are twice as far from us move twice as fast. Another consequence is that the universe is expanding in every direction. This observation means that it has taken every galaxy the same amount of time to move from a common starting position to its current position. Just as the Big Bang provided for the foundation of the universe, Hubbles observations provided for the foundation of the Big Bang theory.

 

Since the Big Bang, the universe has been continuously expanding and, thus, there has been more and more distance between clusters of galaxies. This phenomenon of galaxies moving farther away from each other is known as the red shift. As light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched.

 

 

and yet from NASA

 

WMAP Big Bang Concepts

 

Please keep in mind the following important points to avoid misconceptions about the Big Bang and expansion:

 

The Big Bang did not occur at a single point in space as an "explosion." It is better thought of as the simultaneous appearance of space everywhere in the universe. That region of space that is within our present horizon was indeed no bigger than a point in the past. Nevertheless, if all of space both inside and outside our horizon is infinite now, it was born infinite. If it is closed and finite, then it was born with zero volume and grew from that. In neither case is there a "center of expansion" - a point from which the universe is expanding away from. In the ball analogy, the radius of the ball grows as the universe expands, but all points on the surface of the ball (the universe) recede from each other in an identical fashion. The interior of the ball should not be regarded as part of the universe in this analogy.

By definition, the universe encompasses all of space and time as we know it, so it is beyond the realm of the Big Bang model to postulate what the universe is expanding into. In either the open or closed universe, the only "edge" to space-time occurs at the Big Bang (and perhaps its counterpart the Big Crunch), so it is not logically necessary (or sensible) to consider this question.

It is beyond the realm of the Big Bang Model to say what gave rise to the Big Bang. There are a number of speculative theories about this topic, but none of them make realistically testable predictions as of yet.

To this point, the only assumption we have made about the universe is that its matter is distributed homogeneously and isotropically on large scales. There are a number of free parameters in this family of Big Bang models that must be fixed by observations of our universe. The most important ones are: the geometry of the universe (open, flat or closed); the present expansion rate (the Hubble constant); the overall course of expansion, past and future, which is determined by the fractional density of the different types of matter in the universe. Note that the present age of the universe follows from the expansion history and present expansion rate.

 

As noted above, the geometry and evolution of the universe are determined by the fractional contribution of various types of matter. Since both energy density and pressure contribute to the strength of gravity in General Relativity, cosmologists classify types of matter by its "equation of state" the relationship between its pressure and energy density. The basic classification scheme is:

 

Radiation: composed of massless or nearly massless particles that move at the speed of light. Known examples include photons (light) and neutrinos. This form of matter is characterized by having a large positive pressure.

Baryonic matter: this is "ordinary matter" composed primarily of protons, neutrons and electrons. This form of matter has essentially no pressure of cosmological importance.

Dark matter: this generally refers to "exotic" non-baryonic matter that interacts only weakly with ordinary matter. While no such matter has ever been directly observed in the laboratory, its existence has long been suspected for reasons discussed in a subsequent page. This form of matter also has no cosmologically significant pressure.

Dark energy: this is a truly bizarre form of matter, or perhaps a property of the vacuum itself, that is characterized by a large, negative pressure. This is the only form of matter that can cause the expansion of the universe to accelerate, or speed up.

One of the central challenges in cosmology today is to determine the relative and total densities (energy per unit volume) in each of these forms of matter, since this is essential to understanding the evolution and ultimate fate of our universe.

Posted
G'day from the land of ozzzzzz

 

So you are saying that spcae doe not expand.

 

Matter expands in space.

Hi Pluto,

 

I think the idea* could be perceived as a "contraction" of matter/energy's wavelengths compared to the total amount of space, but that isn't exactly the idea I was trying to describe, and may have implications that would be disastrous for the validity of the idea itself (especially if the idea of matter/energy contracting becomes a central feature of the idea).

 

*That larger size of space compared to the size of matter/energy (or matter/energy's wavelength compared to size of space) influences the interaction of matter/energy with space.

Posted
Yes that is the redshift effect, but photons from the CMB for example started of at at wavelength corresponding to 3000K and cooled down to 2.73K due to expansion of space,primarily at least.

Yes, due to the recession velocity of our galaxy (which is due to the expansion of space) from where they were emitted some ~13 billion years ago.

Posted

G'day from the land of ozzzz

 

 

Kharakov said

 

 

I think the idea* could be perceived as a "contraction" of matter/energy's wavelengths compared to the total amount of space, but that isn't exactly the idea I was trying to describe, and may have implications that would be disastrous for the validity of the idea itself (especially if the idea of matter/energy contracting becomes a central feature of the idea).

 

 

In my opinion I would not worry about space, but I think your on track with contraction of matter and all its phases.

 

You may find these papers interesting.

 

I'm not trying to prove a point, just sharing the reading.

 

[0903.4938] Thermal Fluctuations and Bouncing Cosmologies

Thermal Fluctuations and Bouncing Cosmologies

 

Authors: Yi-Fu Cai, Wei Xue, Robert Brandenberger, Xinmin Zhang

(Submitted on 28 Mar 2009)

 

Abstract: We study the conditions under which thermal fluctuations generated in the contracting phase of a non-singular bouncing cosmology can lead to a scale-invariant spectrum of cosmological fluctuations at late times in the expanding phase. We consider point particle gases, holographic gases and string gases. In the models thus identified, we also study the thermal non-Gaussianities of the resulting distribution of inhomogeneities. For regular point particle radiation, we find that the background must have an equation of state $w = 7/3$ in order to obtain a scale-invariant spectrum, and that the non-Gaussianities are suppressed on scales larger than the thermal wavelength. For Gibbons-Hawking radiation, we find that a matter-dominated background yields scale-invariance, and that the non-Gaussianities are large. String gases are also briefly considered.

 

 

and

 

Penrose model and how to analyze alternatives to the conventional big bang

00/2008

 

Penrose model and how to analyze alternatives to the conventional big bang

 

We present the Penrose model of a big bang, with black holes collecting matter far in the future and re cycling the collected matter/ radiation via a conformal mapping to a new big bang, as well as present an alternative to this Penrose scheme which may have some merit. This is compared to Smoot's table of results with computational bits for cosmological evolutionary complexity, as well as presenting how a 5 dimensional instanton may factor in for transfer of energy/ matter from a prior to the present universe along the lines of instaton physics presented in Wesson's reference on modern Kalusa-Klein theory
Posted
Do you have a source backing up your claim characterizing multiple singularity points throughout space?

 

Regardless here are some papers on the Big Bang Theory

 

Evidence for the Big Bang

Evidence for the Big Bang

 

But!!

 

THE BIG BANG:

THE BIG BANG

 

and yet from NASA

 

WMAP Big Bang Concepts

 

The reason you cannot find a reference to multiple singularity points throughout space is because it is a misunderstanding of the theory.

 

Hypography Rule 4: "Do not post links to other sites as proof of your claims without commenting what the relevant sites say and why they are important to the current discussion." Stop doing it.

 

~modest

Posted

G'day Modest

 

The posts on the Big Bang were not posts in providing evidence they were opinions from others.

 

I totally disagree with the BIG Bang and the formation of singularities that only exist in theory.

 

I said

 

I'm not trying to prove a point, just sharing the reading.

 

Modest it seems you make statements yourself without supporting evidence.

 

Am I to understand that you think that the universe originated from one singularity?

 

as your words state that its only a theory.

Posted
The posts on the Big Bang were not posts in providing evidence they were opinions from others.

 

I totally disagree with the BIG Bang and the formation of singularities that only exist in theory.

Please stay on topic. This thread is *not* about the big bang or the singularity. Please reread the original post of this thread and keep discussion aligned with that original idea. If you would like to discuss the big bang, use an appropriate thread. Thanks.

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