Facts against BB Theory

On Friday, May 16, 2014 3:13:12 AM UTC-4, Robert L. Oldershaw wrote:
On Thursday, May 15, 2014 2:02:19 AM UTC-4, wlandsman wrote:

same 1966 prescription of Peebles works with zero adjustment or tweaks
but only updated nuclear physics (and better computers). This is one
of the great predictions of modern science -- that the observed
primordial light element abundances can be derived from calculations
of a cooling nuclear plasma in an expanding universe. --Wayne

But an important question is whether these
were true definitive predictions or
whether they should be more accurately
called retrodictions?


They were true definitive predictions.

Were the approximate abundances of various
nuclei already well known? In the cases
of H and He, I think they were known fairly
well from stellar spectra and other data BEFORE
1966.

The deuterium abundance was completely unknown. Peebles (1966) quotes
the solar helium abundance as 25-30 % but notes that an unknown amount
of this helium might be produced by prior stellar generations. By
comparison, the current BBN prediction for Y is 24.85+/-0.02% compared
to the observed Y = 24.65 +/- 0.97 (http://arxiv.org/abs/1309.0047 )


I think Peebles knew the answers he was aiming for.
In that case, you do not have a prediction at all.

Peebles provided an algorithm for computing the light element
abundances. He had no way of knowing that the neutron lifetime would
be adjusted by 2 orders of magnitude in future experiments, or that a
new neutrino would be discovered in 1974.


Also, there have also been problems with He and Li
that have cropped up over the decades, but
it has been relatively easy for model-builders
to offer multiple solutions for 'saving the
phenomenon'.

This is completely false. (You are welcome to provide a reference if
you disagree.) There have been many papers written giving solutions if
there was a disagreement between BBN and observed abundances. But none
of these have ever been needed -- the same 1966 prescription of
Peebles works with zero adjustment or tweaks but only updated nuclear
physics (and better computers). The Peebles paper is one of the great
predictions in modern science.

On 5/15/14, 1:02 AM, wlandsman wrote:
Sometimes a "prediction" can be numerically wrong but still provide a
triumph for a theory. For example, Peebles (1966
http://adsabs.harvard.edu/abs/1966ApJ...146..542P) predicted the
primordial helium and deuterium abundances. His values (Yp =
0.26-0.28) disagree with modern values (Yp = 0.246) for reasons that
are now clear: his assumed lifetime of the free neutron was wildly
wrong, he did not know about the tau neutrino, many nuclear
cross-section had not yet been measured.

In the 48 years since this paper, there has sometimes been tension
between BBN models and observations of primordial abundances. There
must be over 100 papers proposing modifications to BBN such as
inhomogenous nucleosynthesis or exotic neutrinos to provide better
agreement. However these modifications have not been needed, and the
same 1966 prescription of Peebles works with zero adjustment or tweaks
but only updated nuclear physics (and better computers). This is one
of the great predictions of modern science -- that the observed
primordial light element abundances can be derived from calculations
of a cooling nuclear plasma in an expanding universe. --Wayne

Numerical solution of equations 31-36 looks straight forward.
Has anyone done this on Mathematica for public use?

Richard D Saam

On Thursday, May 15, 2014 2:53:24 PM UTC-4, Phillip Helbig---undress to reply wrote:

Do you doubt [inflation's initial conditions] and if so, why?

---------------------------------------------

If there is no resolution of the 60 to 120
orders of magnitude disparity between the
vacuum energy density predicted by field
theories of particle physics and the vacuum
energy density determined empirically in the
cosmological context, can we have much faith,
and faith is the right word, in the theoretical
constructs that particle physicists have tacked on
to the Big Bang model?

In 1988 I commented in the American Journal of
physics and/or a LTTE of Nature that: "the marriage
of cosmology and particle physics seems like an
incestuous affair with a high probability of
yielding unsound progeny."

A separate field for every fundamental particle!!!???

A 10^120 disparity for the VED!!!

A Planck mass of 10^-5 GRAMS and a horrendous
hierarchy problem!!!

Key particles have lifetimes too short to be observed
directly!!

Other key particles reliably No-Shows!!

I stand by my 1988 comment.

In article , "Robert L.
Oldershaw" writes:
If there is no resolution of the 60 to 120
orders of magnitude disparity between the
vacuum energy density predicted by field
theories of particle physics and the vacuum
energy density determined empirically in the
cosmological context, can we have much faith,
and faith is the right word, in the theoretical
constructs that particle physicists have tacked on
to the Big Bang model?

Your assumption here is that the cosmological constant has something to
do with quantum-mechanical vacuum energy. That is not completely clear.

On Wednesday, May 21, 2014 8:47:57 AM UTC-4, Phillip Helbig---undress to reply wrote:

Your assumption here is that the cosmological constant has something to

do with quantum-mechanical vacuum energy. That is not completely clear.
------------------------------------

That seems like a very odd and evasive response.

There are many discussions of this fundamental
problem by particle physicists and astrophysicists.
Every such discussion I can remember explicitly
includes the idea that the two VEDs should be the
same.

Here is Nobelist Frank Wilczek on the VED crisis.

"We do not understand the disparity. In my opinion,
it is the biggest and most profound gap in our
current understanding of the physical world. ...
[The solution to the problem] might require inventing
entirely new ideas, and abandoning old ones we thought
to be well-established. ... Since vacuum energy density
is central to both fundamental physics and cosmology,
and yet poorly understood, experimental research into
its nature must be regarded as a top priority for
physical science."

That seems pretty "clear" to me. How about to you?

In article , "Robert L.
Oldershaw" writes:

Your assumption here is that the cosmological constant has something to
do with quantum-mechanical vacuum energy. That is not completely clear.
------------------------------------

That seems like a very odd and evasive response.

There are many discussions of this fundamental
problem by particle physicists and astrophysicists.
Every such discussion I can remember explicitly
includes the idea that the two VEDs should be the
same.

This is certainly not true of every discussion. Perhaps of every one
you can remember explicitly; I don't know.

Here is Nobelist Frank Wilczek on the VED crisis.

"We do not understand the disparity. In my opinion,
it is the biggest and most profound gap in our
current understanding of the physical world. ...
[The solution to the problem] might require inventing
entirely new ideas, and abandoning old ones we thought
to be well-established. ... Since vacuum energy density
is central to both fundamental physics and cosmology,
and yet poorly understood, experimental research into
its nature must be regarded as a top priority for
physical science."

That seems pretty "clear" to me. How about to you?

In this quote, he does not say that they are "the same"; rather, he says
that both are poorly understood.

I think we agree that both are, or at least vacuum energy in particle
physics is, poorly understood. Thus, it seems quite a leap to equate
them.

Of course, I could come up with a quote supporting the view that they
are not necessarily related.

Le 02/05/2014 22:31, Dan Riley a écrit :

But let's review what they are doing. Sutter et al. want to compare
observations to models. The observations are taken with a particular
instrument, at a particular location, covering a particular region of
the sky. To compare the models with the observations, they want to
replicate the effects of observing their simulated data in the same
way the real observations are taken. This is the function of the
"survey mask", which accounts for the geometrical and other effects of
the actual observations.

Thanks for yur answer, it was very informative about the paper and...
about me!

The mask is necessary to account for the observational parameters, as
they say. I would agree with that of course, and I am not competent to
doubt their derivation of their mask. I just assume it is right.

True, I misunderstood the paper in that part I cited, since I was lost
in the different models they use. Apparently in the other model their
model really fits the data, once the mask is applied.

Why did I misunderstand the paper?

It would be wrong to assume anything else than my reluctance to accept
this big bang hypothesis.

Does this bias make me any less scientific than I should be?

Probably. There is a high probability that I see with less enthusiasm
evidence for a theory that tells me that the universe is 13.7 Billion
years old. I am biased.

Somehow I just can't swallow that time scale. Our planet, an
infinitesimal part of this universe, has 4.7 billion years of age. The
life expectancy of the sun (a normal star like other trillions) is 10 GY
and small stars (that are even more abundant than the sun) have a life
expectancy bigger than the age of the universe.

I just can't accept that timescale.

My argument concerned the voids, and at the speeds that galaxies travel
(300-400 Km/sec even 600 Km sec) it would take QUITE a long time for a
galaxy to get out of the void. The time scale to evacuate those voids is
much longer than 13.7 GY.

There was nothing about my original question in that paper.

Like geologists looking at the sediments in the XIX century and
wondering if all that could be done in only 6500 years.

To evacuate the voids you need a much longer timetable.

It is possible to calculate the time a galaxy X needs to cross 250
Million light years. Supposing an incredibly high speed for a galaxy of
1000 Km/Sec, still it is only 1/300 of the speed of the light, i.e. you
need a factor of 300, or around 250 x 300 = 75 GY.

OK, OK. The void was smaller when the universe was smaller, space has
been expanding, there is a factor to subtract.

But 75 GY is quite far away from 13.7.

jacob

P.S. Voids are fascinating.

Are voids void?

Or do they have invisible matter in form of neutral hydrogen gas at 2.75
K :-) or whatever?

How do we know for sure that they are void?

On Thursday, May 22, 2014 3:31:12 PM UTC-4, jacob navia wrote:
Somehow I just can't swallow that time scale. Our planet, an
infinitesimal part of this universe, has 4.7 billion years of age. The
life expectancy of the sun (a normal star like other trillions) is 10 GY
and small stars (that are even more abundant than the sun) have a life
expectancy bigger than the age of the universe.

Sorry, but our Galaxy is a plutocracy -- only the 1% most massive
stars are of much importance. The massive (10 solar masses) stars are
needed to produce and disperse the heavy elements in supernovae, to
create the massive winds to trigger additional star formation, to
produce the ultraviolet radiation for ionization. The observed heavy
element abundances in our Galaxy shows that there must have been a few
generations of massive stars (since no heavy elements were created in
the Big Bang.) Fortunately, the 5-50 Myr lifetime of massive stars
means that there could be many generations within the 13.7 billion
year age of the universe.

The stellar wind and ultraviolet radiation of our Sun are completely
negligible, though in about 6.5 billion years the Sun will return 0.4
solar masses of mildly nuclear processed material back to the
interstellar medium. But it best to think of massive stars as the
engines that drive galaxy evolution, and the Sun and lower-mass stars
are just long-lived tracer particles along for the ride.

My argument concerned the voids, and at the speeds that galaxies travel
(300-400 Km/sec even 600 Km sec) it would take QUITE a long time for a
galaxy to get out of the void. The time scale to evacuate those voids is
much longer than 13.7 GY.

The voids are not created by evacuating galaxies. Galaxies are born at
the edges of large voids created by cold dark matter. In fact your
argument shows that the universe cannot be too old because otherwise
random motions of the galaxies would disperse them into the voids.

There was nothing about my original question in that paper.

The Sutter et al. paper shows that in standard cold dark matter
cosmology, galaxies will be created at the edges of large voids, in a
very similar pattern to what is observed.

To evacuate the voids you need a much longer timetable.

The voids are not created by evacuation of galaxies.

--Wayne

[Mod. note: reformatted -- mjh]

In article , jacob navia
writes:

Somehow I just can't swallow that time scale. Our planet, an
infinitesimal part of this universe, has 4.7 billion years of age. The
life expectancy of the sun (a normal star like other trillions) is 10 GY
and small stars (that are even more abundant than the sun) have a life
expectancy bigger than the age of the universe.

How do you know these numbers? Because of science.

I just can't accept that timescale.

So why can't you accept science when it tells you the age of the
universe? Actually, this number is probably better known than the age
of the Earth or the life expectancies of stars.

Of course small stars have a life expectancy much longer than the
current age of the universe. There is no problem here, since this
applies mostly to the future. Suppose I buy some land and build a house
on it, a robust house of stone. A year later someone walks by and
says "This house will probably last a few centuries, at least; I can't
believe it's just a year old." Make sense? No.

Le 23/05/2014 09:51, wlandsman a écrit :
The voids are not created by evacuating galaxies. Galaxies are born at
the edges of large voids created by cold dark matter

The paper of Sutter et al doesn't give any explanation for the
appearence of voids. It just doesn't address the subject limiting itself
to void detection, establishing of the mask, and correlating the
observations to some models.

Those models are "lambda cold dark matter" models whatever that is.
Arguing that "cold dark matter" explains anything is impossible since
nobody knows what dark matter *is* (physically, I mean) so anything
derived from an unknown "state of matter" is just wild speculation.

If I take your sentence at face value, voids were already existing at
the early universe what contradicts the BB cosmology of an homogeneous
universe.

you say:

The voids are not created by evacuating galaxies. Galaxies are born at
the edges of large voids created by cold dark matter. In fact your
argument shows that the universe cannot be too old because otherwise
random motions of the galaxies would disperse them into the voids.

1: Voids are negative attractors since anything living in a void feels
the pull of other objects in the universe, repealing from the center of
the void.

2: Galaxies would therefore NOT enter the voids because of gravity and
they would stick together. This fact contradicts your affirmation that
"random motion of galaxies would fill the voids".

Basically then, you just say:

This "dark matter" that nobody knows nothing about explains everything.

Great