Holes in Big Bang

[Michael Mozina]

But Big Bang doesn't fail if any inflationary model fails.

The BB model wasn't founded on inflation.

The reasons for the BB model haven't changed. They're still out there.

If we discover that an explanatory model within that framework fails, it doesn't bring down the framework unless it also exposes fatal problems with the framework itself.

Take evolution, for example. We now have the modern synthesis rather than original Darwinian theory, but nothing that was dropped from the original theory was fatal to the overall Natural Selection framework.

I think that's an important point by the way. Inflation is a relatively 'Johnny come lately' to BB theory (early 80's), as is "dark energy"(late 90's). BB theory could easily outlive both of these ideas.

 

[Michael Mozina]

Not really the answer that I was looking, because in a still homogeneous universe, where would there be concentrations of antimatter?

It could be located outside the visible universe, or even inside our own galaxy.

http://news.softpedia.com/news/Large-Antimatter-Cloud-Discovered-in-Galactic-Core-75831.shtml

 

[Monketi Ghost]

It's not that i can't in practice. It's just that i don't hold any. I have well over 100 scientific papers. All of them are dedicated to quantum physics, and not one of them wholey on cosmology. But is this any surprise? I am not a cosmologist.

Papers, please, published where? Curious.

 

[Dancing David]

My assertion based on scientific fact. Besides, someone else showed i was correct, Micheal, so your question has been answered.

Excuse me, why don't you cite a source. Michael does not demonstrate your point, show where the BBE theory says that hole is too large.

How likely is such a large underdense region in a concordance cosmology? Suppose there
is only one such large underdense region in the whole volume up to z=1. The corresponding
void frequency is then the ratio of the comoving volume of the void to the comoving
volume of the Universe to z=1, which is roughly 3 × 10−5. Is this consistent with CDM?
Void statistics have been done for a number of optical galaxy surveys, as well as numerical
structure formation simulations. Taking the most optimistic void statistics (filled dots in
Fig. 9 of Hoyle & Vogeley, 2004) which can be approximated by log P = −(r/Mpc)/15, a
– 8 –
140 Mpc void would occur with a probability of 5 × 10−10, considerably more rare than our
estimate for our Universe (3×10−5) based on the existence of the cold spot. One must keep
in mind, however, that observational and numerical void probability studies are limited to
rc  30 Mpc; it is not yet clear how these should be extrapolated to rc > 100 Mpc.

Hmmm?

 

[DeiRenDopa]

Thanks for the clarification.

What is "quantum cosmology"? How is it related to "the big bang theory"? What is the relationship between quantum cosmology and inflation (as you understand inflation)? What phenomenology is there concerning "the planck time"?

Which paper - published in relevant, peer-reviewed journals - may an interested reader refer to to compare your answers to the above questions to the common views found in the cosmology community?

Quantum cosmology is when one deals with the universe when its very very small, when its not too far off planck scales are taken into consideration. The idea is to treat the universe like a particle, understanding ground and excited states, relativity applied to time, and how planck time is taken into consideration, which has a value of around [latex]5.3(10^{-44})[/latex] which is the smallest known time some kind of action can be performed. It's very important in particle physics, and gives the specific amount of time in which a universe is allowed to prevail from the nothingness at t=1, the very first instant of the big bang, which was the billionth part of the billionth part of the billionth part of the billionth part of the billionth part of one second.

I read this yesterday, several times.

It made essentially no sense to me, so I decided to sleep on it.

I've read it today, also several times.

I'm sorry to say that it still makes essentially no sense.

In fact, it reads like someone who's skimmed a few popsci articles, maybe a chapter or three of a book or four, and strung snippets together.

Let's take a few parts, shall we? "when one deals with the universe when its very very small" ... perhaps you meant to write "the observable universe"; otherwise why do you consider only a finite universe?

"relativity applied to time" - huh?

Also, you said nothing about any connection between inflation and quantum cosmology.

Too, you left out General Relativity (it seems); why?

New question: does quantum cosmology produce any observables, that differ from any other approach to cosmology?

I'll need to look for papers another time.

It might be a good idea to raise the priority on this; I for one find your posts only poorly connected to the world of real science.

 

[Dancing David]

Abstract that the alleged fig 9 is taken from
http://simbad3.u-strasbg.fr/cgi-bin/cdsbib?2004ApJ...607..751H

There is good agreement between the VPFs of the Center for Astrophysics survey and the 2dFGRS. Comparison of VPFs measured for the 2dFGRS with the distribution of simulated dark matter halos of similar number density indicates that voids in the matter distribution in ΛCDM simulations are not empty enough. However, semianalytic models of galaxy formation that include feedback effects yield VPFs that show excellent agreement with the data.

 

[Michael Mozina]

Excuse me, why don't you cite a source. Michael does not demonstrate your point, show where the BBE theory says that hole is too large.

What, you don't like the first reference?

http://arxiv.org/PS_cache/astro-ph/pdf/0405/0405341v2.pdf

From the conclusion:

The probability of having such spot for a Gaussian model is of only (approximately) 0.2%, which implies that, if intrinsic, The Spot has not been originated by primary anisotropies in the standard scenario of structure formation since standard inflation predicts Gaussian fluctuations in the matter energy density and therefore in the CMB temperature fluctuations. When this spot is not considered in the analysis the rest of the data seem to be consistent with Gaussianity.

 

[DeiRenDopa]

Perhaps we can make this discussion more productive by offering thoughts on some of the alternatives presented, so far. For example:

Does anyone know why or why wouldn't either the Ekpyrotic model or the PC/EU theory make a good replacement for inflation and/or Big Bang?!

Let's try to discuss the "competing arguments", not the people making the arguments, please!

Much has already been written on this, but maybe a few new points ...

First, there is no such thing as "EU theory", in any scientific sense (so it cannot, by definition, make any sort of scientific replacement, for anything).

Second, "PC theory", as defined by Lerner (and thanks to Z for bringing this definition to our attention) is also non-science. Why? Because it declares General Relativity (GR) to be not applicable to the study of the universe. And why does it do that? Perhaps it references voluminous research showing GR to be inconsistent with observations on Mpc (and above) scales? No, it makes a simple declaration. Given that there is a very great deal of observational evidence to suggest that GR's domain of applicability extends to the largest observable scales (and essentially none to the contrary), I don't see how this arbitrary assumption could be considered scientifically valid.

Third, "PC theory", as defined by Alfvén, has been shown to be inconsistent with a wide range of high quality observations, so it is no longer a serious cosmological model (and hasn't been for several decades).

 

[Monketi Ghost]

Isn't it amazing how someone can hold themselves up as an authority on a given subject, mystify experts with confusing statements that are not even self-consistent, and yet insist they are correct?

I don't think this post can be edited out of the thread, though, since there's no way to determine which expert or authority I might be referencing.

 

[DeiRenDopa]

And no. Show me were i am wrong in th logic?

OK ...

Here's what you wrote: "The big bang and inflation are arguably components of the same thing, and since the big bang encompasses everything, then inflation is truely everything as well".

In terms of the logic, we can replace "inflation" with anything at all (I'll get onto the first part of the sentence later), "my pet lizard" say: "since the big bang encompasses everything, then my pet lizard is truely everything as well". I.e. nonsense.

Now for the first part. Let's assume it is OK, in terms of the physics, and look at the logic. "Electrons and cold dark matter are arguably components of the same thing" (i.e. the observable universe) is a logically equivalent statement, which illustrates a logical flaw: the union of two subsets is not necessarily equivalent to (or equal to) the original set.

Now add the "since the big bang encompasses everything": we have the big bang being a component of itself, which is a little cumbersome but not illogical, and inflation being a subset of the big bang.

Questions?

 

[DeiRenDopa]

I don't think you have this quite clear. Comparing the models:

Ekpyrotic theory:
The collision of two branes gives us a dense, hot, super-horizon-equilibrated universe with scale-invariant density fluctuations.
This hot Universe begins a Hubble expansion
The universe cools through the GUT (?) SUSY (?) and electroweak symmetry breakings
Big Bang nucleosynthesis leaves us with a H/D/He/Li plasma
The density fluctuations seed acoustic reverberations
The universe cools below 6000K and photons (later to be the CMB) escape, carrying information about the density fluctuations
The remaining overdensities grow nonlinearly into galaxy clusters and voids


Standard inflation theory:
Inflaton-driven expansion gets us from an unknown initial state to a dense, hot, super-horizon-equilibrated universe with scale-invariant density fluctuations.
This hot Universe begins a Hubble expansion
The universe cools through the GUT (?) SUSY (?) and electroweak symmetry breakings
Big Bang nucleosynthesis leaves us with a H/D/He/Li plasma
The density fluctuations seed acoustic reverberations
The universe cools below 6000K and photons (later to be the CMB) escape, carrying information about the density fluctuations
The remaining overdensities grow nonlinearly into galaxy clusters and voids

They're exactly the same except for the very first step. Even the fluctuations have to be the same, since they're observed at least twice, in the CMB and later in the large-scale structure. If something about the large-scale structure were to invalidate the Big Bang, it invalidates both inflation and the ekpyrotic alternative.

(Note: there may be gravity-wave observables which distinguish these different pre-Hubble-expansion theories.)

No ben, i wasn't talking about Ekyportic here. Stop mixing this up.

(bold added)

Huh?

It was you, Sing, who introduced the Ekpyrotic theory into this thread (in post#24)!

What's going on here? And why did you write "Ekyportic"?

 

[DeiRenDopa]

Then it requires more followers. Some say it is confirmed, others not. One of the latter guys was a friend of mine who even went to the observatory upon hearing the news.

(bold added)

So, science by "because my friend, who is an astronomer, said so"?

You know Sing you'd get a better reception if you had actually done your homework.

As RC showed, the paper which announced the (tentative, provisional) discovery of the giant void was very easy to find ... and it's equally easy to discover that it has been cited 53 times already! True, not all the citations are papers, and not all the papers have to do with whether the observations support a conclusion of the existence of a giant void.

Oh, and some of the papers directly address the question of whether such a large void (if there is, indeed, such a thing) can be accommodated within standard LCDM+inflation cosmological models! Would you care to guess what they conclude?

 

[Badly Shaved Monkey]

Papers, please, published where? Curious.

When he said this;

"Originally Posted by Singularitarian
It's not that i can't in practice. It's just that i don't hold any. I have well over 100 scientific papers. All of them are dedicated to quantum physics, and not one of them wholey on cosmology. But is this any surprise? I am not a cosmologist."

I think he meant that he possesses over 100 papers not that he has published them.

But, that was going to lead me to ask;

Sing, what do you mean when you say you "have" over 100 papers? It's been over 15years since I was an academic and had hundreds of photocopied papers. I thought everyone used online subscriptions now.

 

[sol invictus]

There are so many basic misconceptions here it's hard to know where to even start....

1) The big bang is really not a theory at all. It's a large set of empirical observations (redshift/distance, CMB, etc.) taken over the last century that tell us that the universe is expanding. Combined with some very minimal theory - essentially just general relativity and standard particle physics - that implies that the universe 13.7 billion years ago was very hot and very dense. What happened before that isn't known.

2) Do very large voids challenge this picture? Quite the contrary - one of the biggest mysteries of the big bang (which is resolved by inflation) is the relative lack of such features. Matter clumps under the influence of gravity, creating structures like galaxies and galaxies clusters, and leaving voids between them.

3) The void referred to in the OP probably does not exist. See http://arxiv.org/abs/0805.2751

4) The cold spot in the CMB is mysterious only if inflation lasted a "long" time - more than long enough to solve the isotropy and homogeneity problems of the big bang. If inflation was relatively short, such features are to be expected. On top of that, it's not really not all that unlikely even if inflation was long: .5% sounds small, but you have to realize that if you make 200 observations, you should expect one to be unlikely at that level, and there are many, many, many observations.

 

[sol invictus]

I read this yesterday, several times.

It made essentially no sense to me, so I decided to sleep on it.

I've read it today, also several times.

I'm sorry to say that it still makes essentially no sense.

Nothing Sing says makes any sense. He gets just about 100% of everything wrong, from big picture down to the silliest details:

ps. CBM, Cosmic Background Microwaves

It's actually useful for anyone reading these threads - you can be very confident that if he says anything you manage to make sense of, it's wrong.

 

[Wowbagger]

But those "dark flows" demonstrate that inflation is not particularly 'precise' at making any specific predictions.

But, it has been precise in other areas, such as CMB analysis.

The "dark flows" might be large enough to not have been predicted by the model, but it is legitimate to adjust the model.

If someone comes in with a better model, to replace it, we will use that one, instead.

We don't toss out Newton's gravity, just because Einstein made corrections to it.

As for your EU/PC pet theory, perhaps you can respond to DeiRenDopa's points:

(I bolded that last key phrase, which I think you should especially address.)

First, there is no such thing as "EU theory", in any scientific sense (so it cannot, by definition, make any sort of scientific replacement, for anything).

Second, "PC theory", as defined by Lerner (and thanks to Z for bringing this definition to our attention) is also non-science. Why? Because it declares General Relativity (GR) to be not applicable to the study of the universe. And why does it do that? Perhaps it references voluminous research showing GR to be inconsistent with observations on Mpc (and above) scales? No, it makes a simple declaration. Given that there is a very great deal of observational evidence to suggest that GR's domain of applicability extends to the largest observable scales (and essentially none to the contrary), I don't see how this arbitrary assumption could be considered scientifically valid.

Third, "PC theory", as defined by Alfvén, has been shown to be inconsistent with a wide range of high quality observations, so it is no longer a serious cosmological model (and hasn't been for several decades).

DeiRenDopa, perhaps you could contribute a few examples of these inconsistencies, if it is not too much trouble?

 

[sol invictus]

Coming late to this...

From Singu's first link;

" As photons of light fall into the gravity well of a massive object like a galactic cluster, they gain energy and are blue-shifted.* On emerging from the gravity well, such photons would lose the energy gained, except that, due to the accelerated expansion effect of the large quantity of dark energy in the universe, there is a net repulsion acting and it is a bit easier to get out of the gravity well, so that not all of the gained energy is removed.* The net result is that CMP photons that pass through regions containing significant mass arrive at our detectors with a bit more energy on the average than those passing through regions of the universe that are relatively empty.* Therefore, the CMB radiation should appear cooler along a line of sight passing through a large “empty” region."

Can someone explain why this generates a cold spot not a hot spot given that the described mechanism suggests that the photons arrive with more not less energy.

What that says is that overdensities make hot spots. Ergo, voids make cold spots. It's called the late time integrated Sachs-Wolfe effect, if you want to read more about it.

 

[Monketi Ghost]

I think he meant that he possess over 100 papers not that he has published them.

I thought so too, just want to know whom he cites and where I can read them, so I can try to figure out what he thinks supports his statements aside from his own ideas.

 

[sol invictus]

I thought so too, just want to know whom he cites and where I can read them, so I can try to figure out what he thinks supports his statements aside from his own ideas.

Except that whenever he does provide a "reference" for a claim he's making, it's just something he found on the web containing a few of the same key words. Then he claims it proves him right, because (to take a recent example) he said something that include the phrase "720 degrees" and so does his source.

 

[Michael Mozina]

But, it has been precise in other areas, such as CMB analysis.

Technically, unless I'm missing something inflation is not required to explain that feature. I've read a number of articles now as to why starlight cannot explain these features, but I can't tell if any of these methods were applied to 'expanding" stars, or whether it's applied to just a static universe model. I would think any type of 'bang' with surface of last scattering would suffice and that inflation is optional, but feel free to correct me if I am mistaken on that point.

The "dark flows" might be large enough to not have been predicted by the model, but it is legitimate to adjust the model.

Not IMO. IMO you're simply "fudging the numbers" with more ad hoc property assignments. You seem to be refusing to even consider the idea that inflation is falsified. If there are no ways to falsify the theory, then how is it any different from religion?

If someone comes in with a better model, to replace it, we will use that one, instead.

Well, if we apply this logic, then anything and everything that would ordinarily falsify inflation can eventually be accommodated in some "new and improved" brand of inflation. Since none of these new "properties" can be "tested" or falsified, how is this not a religion?

We don't toss out Newton's gravity, just because Einstein made corrections to it.

Yes, but gravity shows up in the lab and has definite properties that can in fact be 'tested' in an ordinary manner.

As for your EU/PC pet theory, perhaps you can respond to DeiRenDopa's points:

If I did, it would be for your benefit, not hers. I believe she (he) has me on ignore at this point. DRD is wrong on almost every count. Birkeland made actual "predictions" that came from real "empirical experiments". These were things that he "learned" from his physical experimentation process, not things he simply "postdicted" based on observation. That is real "prediction". What's done with inflation is 'postdiction". Guth 'postdicted" the homogeneous "property' of inflation not from a real physical experiment, but based upon his 'belief' (at the time) that the universe was homogeneously distributed. All the "properties" he assigned to inflation were "ad hoc fabrications", not something he learned about during active empirical experimentation in controlled conditions like Birkeland. Inflation has always been "postdicted" to "make it fit' and there has never been a single inflation "prediction" that was accurate the first time.

EU theory is a "solar system applicable" theory. Unlike inflation, dark energy and dark matter, 'electrical current' does in fact show up here on Earth and inside our solar system, like we see in solar flare activity. These are in fact true 'predictions' of EU theory. Birkeland actually created and filmed coronal loops in his experiments. He created 'jets' in his experiments. He created aurora in his experiments. He literally 'predicted' these things from empirical experiments and he was surprised by these features. That is what real 'prediction' is all about. EU Theory isn't really a "big picture' theory in the same sense of creationist theories. It doesn't "assume' a creation event took place. One may have occurred of course, but that isn't a direct "prediction" of EU theory. Alfven's 'big bang' theory for instance was more of a cyclical event that required the existence of preexisting matter/antimatter galaxies and stars in order to occur. There is no particular 'need' for a creation event in EU theory. Comparing these two theories is therefore difficult at best, and it's a lot like comparing apples to oranges. Whereas inflation theory was intended to 'explain' a creation event, EU theory was created to explain features and phenomenon inside our own solar system and it works *OUTWARD* from there. These theories are therefore difficult to compare in one to one terms. That does not mean that EU theory isn't a valid cosmology theory. It simply attempts to 'explain' different cosmology features, specifically features that can be 'empirically tested'. In fact Birkeland's whole purpose in creating his lab experiments was to 'explain' aurora, not some "distant event".