Ned Wright's TBBNH Page (C)

Joseph Lazio wrote in message
...
"g" == greywolf42 writes:
[regarding what was known from astronomical measurements regarding the
mass of the (electron) neutrino about 1990]

g First, here is yet another 'value' of the upper limit -- 15 eV.
g Obviously, there was only one event, and there was only one set of
g data to be analysed -- in 1987. If you pick and choose your
g analyses to find the largest number, you can come up with an upper
g limit that barely makes up 'enough' neutrino mass to make up the
g 'missing mass.' So far in this thread, we've seen contemporary
g references of 23 and 15 -- and Ned Wright's estimate of 5 eV. All
g from the same data. And all marginal, at best.

For other readers of the newsgroup, it might be worth pointing out two
facts. First, the Standard Model of particle physics (at the time)
expected that the mass of the electron neutrino (and the other two
neutrino species) would be 0 eV, so any value is significant (though
perhaps not cosmologically).

Yep. And as no value had been measured, so there was no reason to 'expect'
it to be non-zero. Certainly not in the 5 eV range.

Second, one must understand that many measurements in astronomy are
not made to the 50th decimal point, as in some branches of
experimental astronomy. As an initial measurement (or upper bound) on
the electron neutrino mass 5 eV ~ 15 eV ~ 23 eV. These various
estimates are all within a factor of 4 of each other, not so bad for
an initial measurement given the uncertainties and the fact that we
don't control the supernova explosion.

But none of them were in any way measurements of mass. All were simply the
maximum that could not be ruled out -- even when ignoring the physical
nature of the supernova.

greywolf42
ubi dubium ibi libertas

greywolf42 wrote:

Bjoern Feuerbacher wrote in message
...
greywolf42 wrote:

Bjoern Feuerbacher wrote in message
...

I thought I had hit 'save' instead of 'send', but an earlier
draft of mine
went into my files as sent. But it hasn't shown up on the
newsgroups. My
error, apparently. My apologies if this becomes a
semi-duplicate.

I'm trying to tie up the various dangling threads with Bjoern.
Most of the
details apply to the "references" post provided by Bjoern. Since
that's the
most concrete of the three parallel posts in this thread. Almost
everything
contained in the other two are repeats of arguments made herein.

{snip higher levels}

First:
G.G.Raffelt, What have We Learned from SN 1987A?, Modern
Physics Letters
A, vol.5, no.31, 20 Dec. 1990 p.2581-92.
(notice that this is a review article; what is told in it
wasn't known
only at the end of 1990, but already earlier - e.g., a
reference is
given to a paper by Loredo and Lamb from 1989).

References don't always share conclusions.

Err, this reference was given explicitly for the value of the
neutrino mass reported in this paper.

Then why didn't you say so? "A reference is given to a paper..."
does not tell me what the reference is used for.

1) I thought that was clear from the context.
2) I expected you to look the paper up for yourself, then you would have
seen this.


This paper wouldn't have
been accepted for publication, if there weren't at least
something new.

Right, probably there was something new; however, the bound for
the
neutrino mass reported therein was known already before (the
paper by Loreda and Lamb, and several others).

Again, your statement did not indicate this, your reference
wasn't listed in ADS, and I haven't gotten to the library to
check it out. How was I to know? (Try not to skip interim steps
when you write.)

Why didn't you go to the library in order to look at this paper *before*
answering my post?


This article gives the limit of the mass of the *electron*
neutrino
obtained from the observation of the supernova (eq. 9):
m_{\nu_e} 23 eV (at 95% confidence level).

What neutrino pulsewidth did this paper use? (The paper is
not in NASA ADS)

Try going to the nearest university library. The journal
"Modern Physics Letters" should be available there".

I said I would, what's your problem?

My problem is that you ask me questions instead of first going to the
library and looking up these things for yourself!


Unfortunately, as far as I can see, the neutrino pulse width
isn't given in this paper.

There are very little actual calculations in
it; as I already mentioned, it's a review article - and
therefore mainly
gives results. The reference given for the value of 23 eV/c^2
for the
bound on the electron neutrino mass is:
T.J.Loredo and D.Q.Lamb, Ann. N. Y. Acad. Sci. 571 (1989) 601.

Even more unfortunately, that journal isn't available at the
university library here...

Let me provide another contemporary reference. The standard
text, "The
Stars: their structure and evolution," R.J. Tayler, 2nd ed, 1994,
p 303.

1994? Didn't you insist that we talk about the knowledge of 1991?


"Although only about twenty neutrinos were detected, a
considerable amount
of useful information was obtained. ... (T)his observation places
an upper
limit to the mass of the electron neutrino. If a neutrino has a
very small
mass its velocity is not quite equal to c and the velocity
depends on the
energy of the neutrino. The spread of neutrino arrival times at
Earth can
arise from three sources: spread of times of emission, differing
travel
time from different points in the pre-supernova and variation in
neutrino
energy. If the whole spread of travel times is attributed to
neutrino mass,
which cannot be correct, an upper limit to the neutrino mass of
order 15 eV/c^2 is obtained. ..."

First, here is yet another 'value' of the upper limit -- 15 eV.

Does he provide a reference for this number? Apparently not. I would
rather rely on a review article for such data than on a book.


Obviously,
there was only one event, and there was only one set of data to
beanalysed -- in 1987. If you pick and choose your analyses to
find the largest number,

I didn't do this. I simply looked for a review article which summarizes
what was known about the neutrino mass from the SN measurements in 1991
(and even already in 1990).


you can come up with an upper limit that barely makes up
'enough' neutrino mass to make up the 'missing mass.' So far in
this thread, we've seen contemporary references of 23 and 15

Well, the number my review article gives comes from a paper which was
published *before* Lerner's book; your number comes from a book which
was published afterward. Hence if we want to discuss the available
knowledge in 1991, your reference is rather irrelevant.



-- and Ned Wright's
estimate of 5 eV. All from the same data.

Ned's estimate isn't from the data. He uses the data to demonstrate that
a neutrino mass of 5 eV could not have been detected, but he doesn't
place an upper bound on the mass which could have been not detected.


And all marginal, at best.

Why do you consider these to be marginal?


Second you only get your "upper bound" by ignoring the rest of
the physics -- by assuming an instantaneous collapse to a
mathematical point,
with neutrinos emitted only at a mathematical point.

I don't recall that the review article I cited uses this rather
unphysical model. Are you sure about this?


Which Tayler
explicitly notes "cannot be correct." This is why I asked about
the neutrino pulse width in your reference. You missed the
significance of the question.

No, I know that the pulse width is significant - even Wright uses it in
his calculation!


Which indicates that you never really thought about
what was contained in that 'upper bound' you were pushing.

Wrong. I know quite well what is contained in that upper bound - the
review article I cited explains in some detail how the bound was
established (unfortunately without giving explicit numbers or formula;
the review article states that these can be found in the article by Lamb
and Loredo).


I did find a different paper with the same date and author:
"Core mass
at the helium flash from observations and a new bound on
neutrino
electromagnetic properties" ApJ, Part 1, vol. 365, Dec. 20,
1990,
p. 559-568. But nothing on SN1987a or neutrino mass.

So what? Do you want to pretend now that the paper I cited
above doesn't exist, or what?

No aspersions were being cast upon yourself. However, I have had
bogus references provided to me in this newsgroup before.

Well, that's a pity. Nevertheless, the article I quoted *does* exist.


I thought it possible
that you might have made an error when citing the reference (we
all make mistakes).

Well, I used the very reference I gave you later again to find the
article again in order to look up some more details, hence the citation
I gave you should be correct.


Since the paper you cited doesn't show up in ADS, but there is
another paper with the same author and same date. The concurrent
publishing of two different papers by the same author on the same
calendar date is improbable -- especially when one is in ADS and
the other isn't. Which is not to say it didn't happen.

Well, the paper exists, hence it did happen.

It does show up in the INSPEC database; do you know that database? The
paper you mention above, "Core mass...", does show up there, too.


Second:
E.W.Kolb, M.S.Turner, The early universe, Frontiers in
Physics,
Addison-Wesley (1990). This is a well-known book on
cosmology by two
famous cosmologists; it summarizes what was known on
cosmology back then
and hence includes lots of things which were already long
known at that
time. Equation (5.33) is the interesting one in that book:
\Omega_{\nu} h^2 = m_{\nu}/91.5 eV
(hey, the 92 eV which I remembered where quite accurate!).

Excellent.

I don't know exactly what value of h was available back
then, but let's
use the (quite high and therefore favourable for you!)
value of h = 0.8.

According to Peebles' "Principles of Cosmology," 1993,
equation 3.18, the values of h were between 0.5 and 0.85.

Well, then the value 0.8 *is* indeed rather high.

It's not 'high' at all. It's within the 'expected' range.

It's a high value within the expected range. Sorry, I don't see any
contradiction here.


But just for fun, I'll do it again with 0.85:
\Omega_{\nu} = m_{\nu}/66.11 eV,
which, when inserting the bound mentioned above, gives
\Omega_{\nu} 0.35
- which is still a very significant number.

A moot point, however, because Lerner never mentioned
'significant.'

Well, 0.35 * 3 (three neutrino flavours) = 1.05, hence "filling up the
universe" (which *were* Lerner's words) still isn't excluded.


Then we get:
\Omega_{\nu} = m_{\nu}/58.56 eV.


Putting these two things together

Is there a reference where these two *were* put together,
prior to 12/1990?

I don't know, but this would be absolutely obvious to do! This
*is* the
way to determine if the neutrino mass is cosmologically
significant or
not - hence if Lerner claims that the SN observations showed
that the
neutrinos don't have such a mass, then he *must* have used this
formula.

Lerner never discussed 'cosmological significance.'

Well, he discussed if they are able to "fill up the universe". That's
the same formula. If one wants to determine what contribution to the
mass of the universe the neutrinos make, one *has* to use this formula.
It's the standard one.


And we don't know what formula he used.

If he used any other formula, he didn't use the Big Bang Theory - and
thus he couldn't claim that the SN measurements ruled out the
possibility that the neutrinos could make up the missing mass in the
BBT.


He may have had a different constant than you provided.

What constant? The 91.5eV? This constant follows from straightforward
calculations; and, as I explained elsewhere, this formula was very
well-known in 1990 (it was proposed first in 1966!).


We don't know what value for neutrino mass that he used (or
referenced).

Well, if I would make such pronouncements, I would use an accepted value
for the neutrino mass bounds - in other words, I would use a mass from a
review article. If Lerner didn't do this, that's just incompetence on
his side.



We don't know what equation he used (or referenced).

See above.


So there's no *must* about it.

He *must* have used this - because otherwise, his whole claim makes
little sense. Using non-established values or formulas in order to claim
that some measurements are a problem for the BBT wouldn't make much
sense.


(which both were known *BEFORE* 1991,
when Lerner published his book!),

My apologies for the confusion on publication date (the
copyright
is given as 1991). The month of the year did not matter,
prior to your proffering of a
December 1990 paper and a book published in 1990.

According to the preface of TBBNH, the first edition was
published in "late
1990," a "year and a half" before the completion of the
preface (written for a
different publisher) in "May, 1992." So the first paper was
undoubtedly published AFTER TBBNH was printed.

Well, the paper of Loredo and Lamb mentioned above, from which
the this
review article took the value of 23 eV, was published in 1989.

Now a moot point. But I still would like to know the month in
1990 when the Kolb book was published? Did it also come up in
December (i.e. post-TBBNH)?

The book itself gives only the publication year, but there is a
stamp in it which says that the library here bought it in February of
1990; hence it must have been published very early in 1990.


we get:
\Omega_{\nu} 0.39.
Obviously, a value of 0.39 *IS* quite significant
cosmologically!

And using Ned's value of 5 (calculated in 2000), we get a
value of .39 (5/23) = .08.

Which still would be significant.

Now a moot point.

Right, Wright's numbers aren't demolishing to Lerner's claims. However,
the numbers in the review article *are* (because 0.35*3 1).



Hence, contrary to Lerner's claims, the supernova
observations did *not*
rule out a mass for the neutrino which would have been
cosmologically
relevant. Lerner is wrong there, live with it.

And now we return to what Lerner actually claimed in TBBNH.
Lerner did not make any claims about neutrino mass that was
'cosmologically interesting' or 'cosmologially relevant.'

{You made an 'invisible' snip. Can I guess why?}

What do you mean by "invisible"? That I didn't mark it? If yes, then
sorry; I always try to mark my snips and often even remark *why* I
snipped these things. Apparently, I forgot this here, sorry.


I repeat the quotes you gave from Lerner's book here (with
slight spelling corrections, and some added comments):

And I will bypass commenting on your individual comments until
you are through.

"Cosmologists weren't perturbed, though, because particle
theorists had
provided an entire zoo of particles to make up the missing
mass."

Lerner insinuates here that these particles were all made up
only
because of the problem of missing mass, which is quite wrong.
Lots of
these particles were theoretical predictions which weren't in
the least
based on the fact that there was apparently missing mass in the
universe.

"First came heavy neutrinos."

I very much doubt that these came first. IIRC, they were one of
several parallel proposals.

"Neutrinos are real particles, observed in laboratory
experiments, but
they are quite hard to detect because they interact so little
with
matter. They appear to travel at the speed of light, so must
have no mass."

Jumping to conclusions. From "appear to travel at the speed of
light"
does not follow "must have no mass" - only "must have at most a
mass of
x eV/c^2", where x is a number which can be calculated from the
sensitivity of the velocity measurements.

"However, particle theorists postulated that neutrinos do have
mass,"

Well, that postulate wasn't a big deal. Yes, the Standard Model
at that
time treated the neutrinos as massless - but there was no
theoretical
reason at all why they really should be massless; the SM mainly
treated
them as massless because it was already known that their masses
must be
very low and hence are negligible for most effects.

"and some cosmologists decided that these massive neutrinos
could be the missing mass."

Right, some, not all. Others made other proposals. Sounds a bit
contradictory to "Cosmologists weren't perturbed, though,
because
particle theorists had provided an entire zoo of particles to
make up
the missing mass. First came heavy neutrinos.", IMO.

"A supernova blew away this idea."

Lerner is partly right: the supernova blew away the idea that
the
*electron* neutrinos could provide *all* of the missing mass.
Nevertheless, he conveniently never mentions that the SN
measurements
were not able to place constraints on the *other* neutrino
masses - and
that the SN therefore did *not* blew away the idea that *all*
of the
neutrinos could perhaps provide *all* of the missing mass.

"Supernovas produce large quantities of neutrinos when they
explode. In
1987, when a supernova occurred in the
Large Magellanic Cloud, a satellite galaxy of our own Milky
Way,
scientists were able to detect the neutrinos released, using
the same
arrays that had been patiently waiting for a decaying proton.
The
neutrinos all arrived in a single bunch, showing that they all
travel at the speed of light"

Again, jumping to conclusions.

"and have
either no mass or so little that they couldn't fill up the
universe."

Well, the measurements showed that the *electron* neutrinos
couldn't
"fill up" more than about 0.39 of the universe (very strange
wording
here!). They didn't show anything about the other neutrinos.
Lerner conveniently doesn't mention this.

And my apologies for allowing myself to get sucked into Ned
Wright's diversionary strawman definition of 'interesting
mass.'

I think the greater problem here is that Lerner pretends that
looking at
measurements of the mass of the electron neutrinos is enough to
rule *all* of the neutrinos out as being able to "fill up the
universe".

So, you prefer dishonesty to imprecision?

No. But in contrast to you, I consider Lerner's wording to be dishonest,
and Wright's comments to be imprecise, not the other way round.


If Ned thought there was a problem with focusing on "electron
neutrinos", he could have said so.

Err, he did. Quote (from your original post, where you quoted what
Wright wrote):
"Lerner claims that the neutrinos from SN 1987A in the LMC rule out an
interesting neutrino mass, but the light water detectors used can
essentially only detect electron antineutrinos, so the mu and
tau neutrinos can have plenty of mass."


There then would have been no need to distort Lerner's
statement.

Wright did both things: He mentioned that there is a problem with
Lerner's argument, because they only concern electron neutrinos, and
then he did make a calculation, where he unfortunately distorted
Lerner's view a bit. (come on, "cosmologically significant" and "filling
up the universe" are not sooo much different!)


So I conclude that your own, personal view about the possible
role of mu and tau neutrinos was not shared by Ned Wright.

Wrong. See the quote above. Which you yourself provided in your original
post.


And that he knew
5 eV was insufficient to 'fill up' the universe to omega = 1.0.
So he distorted Lerner's claim, to make it attackable.

I would rather think that he tried to clarify what he was talking about.
Contrary to what Lerner claims, even low masses for the neutrinos aren't
so much of a problem, because there are lots of other theoretical
proposals for dark matter (which weren't all only made up because the
BBT "needs" dark matter, BTW). Hence it is sufficient to discuss if the
SN measurements were able to detect a "cosmologically interesting" value
of the electron mass; it isn't necessary to discuss if the electron
neutrinos alone could "fill up the universe".

Yes, Wright's argument doesn't attack Lerner's argument directly, and
somehow distorts it - but I don't think that this is much of a problem,
if one views these arguments in their context!


What Lerner actually *wrote* begins on p 157 of TBBNH. He is
discussing the genesis of the 'inflationary' Big Bang model
--
and the cosmologists' desire for a value of omega of 1.0.

Well, this value was measured, hence speaking of a "desire"
makes little sense.

ROTFLMAO!! Omega = 1.0 has NEVER been measured!!!!

Well, that depends on how you define "measured". This value obviously
wasn't measured *directly*; it was determined from fits of theoretical
models to the measured data - as in most of physics.
Do you have a problem with such methods?

What is crucial here is that several independet set of data lead to fits
with Omega parameters which agree with each other (within there error
bounds). *I* would call this "Omega = 1.0" was (approximately,
obviously, no measurement is ever exact) measured.


That's what the whole issue of "dark matter" is about!!!!

No, it isn't.


Look at the reference (Peebles) given by Ned Wright! Table 20.1.

I know quite well what "Dark Matter" is about, thank you. I took several
courses here at the university about cosmology, and I've looked at
current research articles, for examples the ones listed at
http://map.gsfc.nasa.gov/m_mm/pub_papers/firstyear.html.


Lerner uses the term "missing mass":

"... Cosmologists knew that an opmega of 1 would solve at
least
the flatness problem and probably the problem of anisotropy."

IIRC, this wasn't the reason to introduce the concept of
"missing mass".
The reason was more that Omega was *measured* to be close to
1.0.

LOL!!! Too rich. Read the reference.

Which? The one to Peebles above? Thank you, I've already read lots about
dark matter.


You just shot any faith I had in your
historical memory. You seem to remember numbers, but not where
they came from.

Well, you appear to have read mainly popular science books. I've had
university courses about this and have read several original scientific
articles about this, in well-established scientific journals - decidedly
not pop-science. So, I doubt that you are qualified to judge my
"historical memory".


And what "problem of anisotropy" does he talk about here?

Read the book and find out.

Nice. Couldn't you give me a small hint first?


"Yet all the
known matter added up to a few percent of that density --
there
just wasn't enough. If the Big Bang was to be saved, there
had to be far
more than we can see, so cosmologists decided that most of
the universe was dark, or "missing. ..."

That's a strong misrepresentation of what actually happened.
Already at
that time, it was known from 1) theoretical predictions

Uh, bubby, that's what Lerner SAID. Theoretical predictions were
the problem. Because the "predicted matter" wasn't observed.

I didn't talk about theoretical predictions of the BBT. I talked about
theoretical predictions from particle physics. And it's no wonder that
the predicted particles weren't observed - it was *predicted* that they
would be very hard to observe! And, again, these were predictions from
theoretical particle physics - these particles weren't just made up in
order to solve the "Dark matter" problem of the BBT!


and 2)
measurements of the rotation curves of galaxies that there
indeed exists
"dark matter". It wasn't made up simply to "rescue" the BBT.

But the theoretical ad-hoc *assumption* of 'galactic' dark matter

Yes, it was an assumption. But calling it "ad hoc" is simply wrong.
Again, as I already mentioned, particle physics had already predicted
the existence of dark matter at that time. And if one detects that the
rotation curves of galaxies don't match the calculated ones, which were
calculated based simply on Newton's law of gravity and the observed
matter, then it's a quite natural assumption that there is dark matter.
I don't see your problem with this.


only got one to omega = 0.1.

Yes, that was the number one got back then, approximately, right. I
think more modern numbers are around 0.3. So what? The measurements were
in its infancy back then, no one could say how much dark matter could
"lurk" out there.


Which was insufficient for the BB. That is, it was
assumed -- it was not *known.*

The value of (approx.) 1.0 for Omega wasn't determined from direct
measurements of the available mass - it was determined indirectly from
other measurements and fits to a model. Again, do you have a problem
with that? If yes, care to suggest another model, which also gives
consistent fits with the data?


The specific statements about SN1987a in TBBNH are on p.160:

[snip - see above]

So, we see that Lerner was describing the "filling up" of the
universe to the desired 1.0 value of omega, from the observed
value of between
.02 to .03. Thus, a value of even .39 is a factor of 3 too
small to "fill up the universe."

Hint: there are three neutrino flavours. 3 * 0.39 = 1.17.

According to Ned, it was only 3 * .08 = .24.

Yes, Wright's numbers don't do it, right. So what? He made an
*estimate*, he didn't use the actual numbers which were published back
then! His main point was to demonstrate that the SN measurements
couldn't have ruled out a neutrino mass of a few eV. And his calculation
demonstrated exactly that.


According to Tayler, it was at
most 3 * .15 = .45

Where do you get the .15 from? You said that Tayler gives a value of 15
eV/c^2 - with h = 0.85, I then get 0.227, not 0.15. 3 * 0.227 = 0.68.
This isn't enough to "fill up the universe", right - but nevertheless,
it makes a very substantial contribution. Taking account that lots of
other "dark matter" candidates existed back then (again, which weren't
invented simply because of problems with the BBT, but which were
predicted independently by particle physics!), this still doesn't rule
out that "dark matter fills up the universe".



-- and that value was 'known to be too high" on it's
face.

In 1994. Weren't we talking about 1990/91?


The paper *you* used (published after TBBNH)

The paper which was quoted therein (Lamb and Loredo) was published
*before* TBBNH.


assumed an instantaneous (i.e. unphysical) supernova.

Did you read the paper in the meantime? Or how do you know?


Thank you for providing calculational support for Lerner's
statements in TBBNH. The main problem was another of Ned's
mischaracterization of Lerner's statements.

You are right, Wright apparently misrepresented Lerner a bit
here.

A BIT????

Is "filling up the universe" and "cosmologically significant" really so
much of a difference for you? Especially in the light of all the
comments I added above?


Here????

Well, I don't know about other instances; I only commented on this short
excerpt.


Wright misrepresented damn near EVERY statement of Lerner's to
which he referred.

I don't know about this, I haven't read Lerner's book. I only wanted to
comment on the specific quotes you gave in your original post.


But what you won't ever admit, apparently, is that Lerner
misrepresented lots of things, too.

Name one.

See my comments way above, which I inserted in the quotes from Lerner's
book. You said you wanted to comment on these later?


What you claim above, is that Lerner was insufficiently detailed.
That is not the same as misrepresenting an argument!

Saying that the SN measurements ruled out the neutrinos as candidates
for filling up the universe *is* a misrepresentation of the actual data.
Saying that these measurements "proved" that neutrinos can have no mass
*is* a misrepresentation of the actual data. That's not merely
"insufficient detail" - it's just plain wrong.


[snip another argument about "cosmologically interesting" and other
repetitions]


But it's even funnier, because you fully believe that
neutrino masses are a factor of 10,000 times lower.

A few years ago, when little data was available (only the LSND
measurements, which were very questionable), I believed that
neutrinos
have no mass. Then came the Superkamiokande measurements, the
SNO
measurements, and some others. This changed my opinion - now I
don't believe any more that neutrinos have no mass. I *know*
that they have a
mass of about 10^(-3) eV/c^2. This has nothing to do with
"belief" - this is based on *experimental evidence*.

OK, I'll reword to remove the word 'belief':

But it's even funnier, because you fully accept that neutrino
masses are a factor of 10,000 times lower.

I don't see what's so funny about this. That we know today that the
neutrino masses are insufficient to explain Dark Matter doesn't change
my argument in the least: Lerner's claim that the SN measurements ruled
out the neutrinos as a candidate to "fill up the universe" is simply
wrong. Based on a review article from 1990, which used data from 1989.
Published before Lerner's book. Your data from 1994 is simply not
relevant for my argument.


Which is not cosmologically significant, let alone capable of
'filling up' the universe to an omega of 1.0.

Right. So what? Weren't you the one who insisted to concentrate
on the knowledge of 1991? Moving the goalposts again?

My point was to concentrate on the statements actually made in
TBBNH (late
1990), and Ned Wright's unprofessional webpage attack on same
(2000). You've
admitted that Ned misrepresented the statements in TBBNH -- by
bringing in a
strawman 'argument by definition.'
*You* -- in 2003, using a reference
published after TBBNH

How often do I have to point out that the relevant article (Lamb and
Loredo) was published already in 1989?


-- have been able to 'just barely fit' an upper bound

1.17 is "just barely fit"? Even 1.05 I wouldn't call "just barely fit".


to declare "it can't be ruled out"

Well, that's obviously right. If the most pessimistic estimate for h
(using 0.85, the upper bound) and the accepted mass bound for the
electron neutrino (23 eV, from the review article, which took this value
from an article from 1989) gives Omega_{mu} 1 (and 1.05 is obviously
1), then stating that the SN measurements ruled this out is just plain
wrong.


-- even though you know the estimate was
fundamentally incorrect

I don't know this. Have you studied Lamb's and Loredo's model?


-- and even though you know that the 'real' value is
at least 10,000 times lower.

Which is absolutely irrelevant for the question in discussion, and you
know that.


But the "truth" remains that the 'massive neutrino' solution for
the Big
Bang *was* generally abandoned during the late 1980s.

The only quote you presented for this so far where from a text which
obviously discusses only electron neutrinos, and from a book from 1994.
Not very convincing, IMO.


And Ned's
misrepresentation of Lerner's argument was NOT the argument you
bring to his defense.

Huh? Sorry, I don't understand this.


The essence of TBBNH (at least that section) is that
'heavy neutrinos' cannot solve the Big Bang's problems.

I never claimed that they are able to solve any (perceived)
problems in the BBT. So what's the problem?

The whole point of the argument in TBBNH is that massive
neutrinos were
postulated to comprise the 'missing mass'

That's one of Lerner's misrepresentations. They were postulated to be
*one possible source* of missing mass. I don't think that anyone ever
thought them to be the *only* component of missing mass!


-- and failed 'round about 1987.

Using the numbers I gave you, you can see that this claim of failure is
wrong.


And Ned Wright and you are busting Lerner's chops for so stating.

Well, because this claim is wrong.


You want
to say -- well yes, Lerner was right about the abandonment of the
theory -- but not JUST because of the reason he mentioned.

Huh? What are you talking about?

[snip a bit]


Contrary to your claim, the other book (Lindley) was not
limited to electron neutrinos.

Wrong. It was. It doesn't say "electron neutrino" explicitly,
right - but it says the following things:

"There was a moment in the early 1980s when it seemed possible
that this
dark matter had been identified. A few experiments around the
world
came up with some evidence that the neutrino, in standard
physics
strictly a massless particle, might actually have a small
mass."

These "few experiments" he mentions here measured only the mass
of the
electron neutrino - hence obviously everything that follows can
refer only to the electron neutrino, too.

Nope. See the *rest* of the quote (which you removed).

*sigh* I *read* the rest of the quote. I *still* think that the text
only refers to electron neutrinos. Yes, he states at the end that
neutrinos have been ruled out as dark matter - but I think he either
only means electron neutrinos there, or that he has some other data
available which rule the mu and tau neutrinos out. Nevertheless, he
doesn't mention anywhere the SN measurements, and therefore the whole
text is *ENTIRELY IRRELEVANT* to the discussion, because (*AGAIN*!!!!!)
my argument is about the claim that the SN measurements were able to
rule out the neutrinos as a candidate for "filling up the universe".


About the
'theoretical' failings -- which AREN'T limited to electron
neutrino experiments.

Which have nothing to do with the question if the SN measurements were
able to rule out neutrinos as a candidate for "filling up the universe"
and are therefore *ENTIRELY IRRELEVANT* to the point in discussion.

I don't want to dispute that neutrinos were ruled out as a candidate for
"filling up the universe". I *ONLY* want to debate if the SN
measurements ruled this out!!! How often do I need to repeat this simple
point until you finally understand it?


See my post of Sept. 10, the content of
which you have snipped.

I explained why I snipped it - I didn't consider it to be of
much
relevance to the question in discussion (if the SN measurements
rule out
an "interesting" mass or not - or, if you prefer, if they rule
out the
possibility of neutrinos "filling up the universe" or not). The
SN
wasn't mentioned in the text, hence I didn't consider it to be
relevant
to this question. What's so hard to understand here?

If anyone expresses the slightest doubt of the BB, you see
nothing wrong
with distortions made to smear the heretic (i.e. Ned Wright
smearing Lerner)?

This question is absolutely ridiculous and has nothing to do with my
comments and explanations above.


And if anyone (i.e. me) dares to point out the arguments are
based
on distortions, *you* go to extreme lengths to support the smear
-- when you
already understand that the point you are pushing is wrong by at
least a factor of 10,000?

Again, this has nothing to do with the comments I made above, with my
arguments or with the original point of the discussion. Don't you have
any arguments left? Do you need to resort to such ad hominems nows? (and
please spare me a comment that these aren't ad hominems!)


I must admit, that I'm not surpised. Only disappointed that such
is the norm here in a "sci." newsgroup.

Typical reaction of a crackpot. As soon as he is proven wrong, he
resorts to personal attacks and pretends that the BBT is something like
a "sacred cow" and defenders of it are so misguided that they
have to resort to exactly the sort of cheap arguments the crackpot
himself is using.


Let's take a look at what you'd like Lerner to have 'more
properly' stated in TBBNH:

In 1987, a "supernova completely blew away the idea that electron
neutrinos could provide all of the missing mass."

Yes, that would have been accurate.


If you ignored the physical time it
takes to make a supernova, and ignored the size of the supernova,
and assumed all of the difference was in travel times, you could
-- just barely -- make up enough mass to fill up the universe.

If you ignore that lots of other candidates were around back then (and
are still around) for dark matter, you can pretend that this rules out
the BBT.


It was not
*absolutely* ruled out that mu and tau neutrinos might be
significantly 'heavier'

Well, most people back then (and still today) assumed that the mu and
tau neutrinos are significantly heavier than the electron neutrino -
simply because the mu and tau are significantly heavier than the
electron. Ever heard of particle "generations" or "families"?


(there being no significant experimental evidence on either) and
make up the 'missing mass.' However, there were also serious
theoretical problems with the 'heavy neutrino' theory, and the
theory was abandoned.
Even though it was not yet 100% disproved by experiment.

Again moving the goalposts. I never talked about the theoretical
problems. My whole concern was always the SN argument.

And what do you mean by "heavy neutrino theory"? The same as "massive
neutrino theory"? If yes, then you are wrong - that theory wasn't
abandoned.


The above paragraph meets the arguments of both you and Ned.

No. Lots of arguments are still missing. Lerner's insinuation that the
SN measurements (or any other measurements about neutrino masses)
disproved the BBT somehow are simply wrong (because, as I already
mentioned, there were several other possible candidates around already
at that time).


Yet the
essence of the information communicated is unchanged.

Wrong, it is changed. Lerner's text, as it stands, implies that the SN
measurements ruled out completely the possibility that neutrinos could
"fill up the universe" and perhaps even the existence of dark matter -
and therefore disproved the BBT. And that is simply wrong.


Since it is now
'accepted' by you that neutrino masses are 10,000 times smaller
than the
'upper bound' estimates that we knew "could not be correct" at
the time.
Why the heck are you trying to bust Lerner's chops?

I explained this several times. Apparentely you are totally unable to
understand what I write.


Hello? Heavy neutrinos filling the universe to omega = 1.0 WERE
abandoned around 1987.

You still haven't provided a reference for this claim.


I'm sure SN1987a played some part in that.

You are sure? Interesting. Any evidence?


Yet both you and Ned Wright fight on!

Well, because Lerner's claim is wrong - BASED ON PUBLISHED NUMBERS.
PUBLISHED BEFORE LERNER'S BOOK.


As if 'heavy neutrinos' were still a valid and ongoing
effort in 1990. And Lerner's description of the abandoning of
the theory
(which is a historical fact) was not SOLELY due to SN1987a, and
it was not
absolutely, positively impossible that 'heavy neutrinos' existed.

*sigh* You really won't ever get the point, will you?


Bye,
Bjoern

greywolf42 wrote:

Joseph Lazio wrote in message
...
"g" == greywolf42 writes:
[regarding what was known from astronomical measurements regarding the
mass of the (electron) neutrino about 1990]

g First, here is yet another 'value' of the upper limit -- 15 eV.
g Obviously, there was only one event, and there was only one set of
g data to be analysed -- in 1987. If you pick and choose your
g analyses to find the largest number, you can come up with an upper
g limit that barely makes up 'enough' neutrino mass to make up the
g 'missing mass.' So far in this thread, we've seen contemporary
g references of 23 and 15 -- and Ned Wright's estimate of 5 eV. All
g from the same data. And all marginal, at best.

For other readers of the newsgroup, it might be worth pointing out two
facts. First, the Standard Model of particle physics (at the time)
expected that the mass of the electron neutrino (and the other two
neutrino species) would be 0 eV, so any value is significant (though
perhaps not cosmologically).

Yep. And as no value had been measured, so there was no reason to 'expect'
it to be non-zero. Certainly not in the 5 eV range.

Err, the reason to suspect that neutrino have mass is that all of the
other elementary fermions have mass - why should the neutrinos be an
exception? That would be rather unnatural.


Second, one must understand that many measurements in astronomy are
not made to the 50th decimal point, as in some branches of
experimental astronomy. As an initial measurement (or upper bound) on
the electron neutrino mass 5 eV ~ 15 eV ~ 23 eV. These various
estimates are all within a factor of 4 of each other, not so bad for
an initial measurement given the uncertainties and the fact that we
don't control the supernova explosion.

But none of them were in any way measurements of mass. All were simply the
maximum that could not be ruled out -- even when ignoring the physical
nature of the supernova.

Giving an upper bound on the mass *is* a measurement of mass.


Bye,
Bjoern

Bjoern Feuerbacher wrote in message
...
greywolf42 wrote:

Bjoern Feuerbacher wrote in message
...
greywolf42 wrote:

Bjoern Feuerbacher wrote in
message
...


{snip higher levels}

Err, this reference was given explicitly for the value of the
neutrino mass reported in this paper.

Then why didn't you say so? "A reference is given to a paper..."
does not tell me what the reference is used for.

1) I thought that was clear from the context.

It wasn't. That's what I was explaining.

2) I expected you to look the paper up for yourself, then you would have
seen this.

Irrelvant.

{snip higher levels}

Again, your statement did not indicate this, your reference
wasn't listed in ADS, and I haven't gotten to the library to
check it out. How was I to know? (Try not to skip interim steps
when you write.)

Why didn't you go to the library in order to look at this paper *before*
answering my post?

Because the library is 100 miles away. And -- as we've seen -- the paper
content was a moot point.

{snip higher levels}

What neutrino pulsewidth did this paper use? (The paper is
not in NASA ADS)

Try going to the nearest university library. The journal
"Modern Physics Letters" should be available there".

I said I would, what's your problem?

My problem is that you ask me questions instead of first going to the
library and looking up these things for yourself!

If you present a reference, supposedly you have read it.

Unfortunately, as far as I can see, the neutrino pulse width
isn't given in this paper.

There are very little actual calculations in
it; as I already mentioned, it's a review article - and
therefore mainly
gives results. The reference given for the value of 23 eV/c^2
for the
bound on the electron neutrino mass is:
T.J.Loredo and D.Q.Lamb, Ann. N. Y. Acad. Sci. 571 (1989) 601.

Even more unfortunately, that journal isn't available at the
university library here...

Let me provide another contemporary reference. The standard
text, "The
Stars: their structure and evolution," R.J. Tayler, 2nd ed, 1994,
p 303.

1994? Didn't you insist that we talk about the knowledge of 1991?

I insisted that you not bust Lerner's chops for not knowing references after
his book was published in 1990.

In this case, the subject is the neutrino pulse width given in a paper you
claimed existed (though the journal isn't in your library). You didn't seem
to think the pulse width was important. My reference is to show you what it
means.

"Although only about twenty neutrinos were detected, a
considerable amount
of useful information was obtained. ... (T)his observation places
an upper
limit to the mass of the electron neutrino. If a neutrino has a
very small
mass its velocity is not quite equal to c and the velocity
depends on the
energy of the neutrino.

(A)

The spread of neutrino arrival times at
Earth can
arise from three sources: spread of times of emission, differing
travel
time from different points in the pre-supernova and variation in
neutrino
energy. If the whole spread of travel times is attributed to
neutrino mass,
which cannot be correct, an upper limit to the neutrino mass of
order 15 eV/c^2 is obtained. ..."

First, here is yet another 'value' of the upper limit -- 15 eV.

Does he provide a reference for this number? Apparently not. I would
rather rely on a review article for such data than on a book.

Then Ned Wright's value of 5 eV is of no value, either?

Obviously,
there was only one event, and there was only one set of data to
beanalysed -- in 1987. If you pick and choose your analyses to
find the largest number,

I didn't do this. I simply looked for a review article which summarizes
what was known about the neutrino mass from the SN measurements in 1991
(and even already in 1990).

And completely ignored the information about the width of the neutrino pulse
GENERATED by the supernova.

you can come up with an upper limit that barely makes up
'enough' neutrino mass to make up the 'missing mass.' So far in
this thread, we've seen contemporary references of 23 and 15

Well, the number my review article gives comes from a paper which was
published *before* Lerner's book; your number comes from a book which
was published afterward. Hence if we want to discuss the available
knowledge in 1991, your reference is rather irrelevant.

The question is not whether you were able to find one (or more) articles
that could (barely) 'fill the universe.' The point is that the DATA was all
the same -- SN1987a. And several different articles come up with several
different values -- including Ned Wright. We still don't know what articles
Lerner was looking at.


-- and Ned Wright's
estimate of 5 eV. All from the same data.

Ned's estimate isn't from the data. He uses the data to demonstrate that
a neutrino mass of 5 eV could not have been detected, but he doesn't
place an upper bound on the mass which could have been not detected.

Ned's claim was that 5 eV was 'cosmologically interesting.' Which was -- as
you have already admitted -- a misrepresentation of Lerner's position. It's
even worse if he 'made up" the value, as well.

And all marginal, at best.

Why do you consider these to be marginal?

Because it leaves no room for the neutrino pulse width -- and because you
reach omega=1.0 only in some papers and not others -- and only by making
additional assumptions.

Second you only get your "upper bound" by ignoring the rest of
the physics -- by assuming an instantaneous collapse to a
mathematical point,
with neutrinos emitted only at a mathematical point.

I don't recall that the review article I cited uses this rather
unphysical model. Are you sure about this?

You said it doesn't mention neutrino pulse width. Thus, the 'upper bound'
mass that it provides is the result of an unphysical model.


Which Tayler
explicitly notes "cannot be correct." This is why I asked about
the neutrino pulse width in your reference. You missed the
significance of the question.

No, I know that the pulse width is significant - even Wright uses it in
his calculation!

Not the pulse at the detector (which Wright uses) -- the pulse at the
supernova. As indicated in the excerpt at (A), above. Try reading it
again. You are assuming "the whole spread of travel times is attributed to
neutrino mass." That is unphysical.

Which indicates that you never really thought about
what was contained in that 'upper bound' you were pushing.

Wrong. I know quite well what is contained in that upper bound - the
review article I cited explains in some detail how the bound was
established (unfortunately without giving explicit numbers or formula;
the review article states that these can be found in the article by Lamb
and Loredo).

Detail? Without explicit numbers? Without formula? Without mentioning
the initial pulse width of the supernova?

I did find a different paper with the same date and author:
"Core mass
at the helium flash from observations and a new bound on
neutrino
electromagnetic properties" ApJ, Part 1, vol. 365, Dec. 20,
1990,
p. 559-568. But nothing on SN1987a or neutrino mass.

So what? Do you want to pretend now that the paper I cited
above doesn't exist, or what?

No aspersions were being cast upon yourself. However, I have had
bogus references provided to me in this newsgroup before.

Well, that's a pity. Nevertheless, the article I quoted *does* exist.

Good.

{snip more about the reference existing}

Second:
E.W.Kolb, M.S.Turner, The early universe, Frontiers in
Physics,
Addison-Wesley (1990). This is a well-known book on
cosmology by two
famous cosmologists; it summarizes what was known on
cosmology back then
and hence includes lots of things which were already long
known at that
time. Equation (5.33) is the interesting one in that book:
\Omega_{\nu} h^2 = m_{\nu}/91.5 eV
(hey, the 92 eV which I remembered where quite accurate!).

Excellent.

I don't know exactly what value of h was available back
then, but let's
use the (quite high and therefore favourable for you!)
value of h = 0.8.

According to Peebles' "Principles of Cosmology," 1993,
equation 3.18, the values of h were between 0.5 and 0.85.

Well, then the value 0.8 *is* indeed rather high.

It's not 'high' at all. It's within the 'expected' range.

It's a high value within the expected range. Sorry, I don't see any
contradiction here.

Specious.

But just for fun, I'll do it again with 0.85:
\Omega_{\nu} = m_{\nu}/66.11 eV,
which, when inserting the bound mentioned above, gives
\Omega_{\nu} 0.35
- which is still a very significant number.

A moot point, however, because Lerner never mentioned
'significant.'

Well, 0.35 * 3 (three neutrino flavours) = 1.05, hence "filling up the
universe" (which *were* Lerner's words) still isn't excluded.

Only by ignoring reality -- the source pulse width.

Then we get:
\Omega_{\nu} = m_{\nu}/58.56 eV.


Putting these two things together

Is there a reference where these two *were* put together,
prior to 12/1990?

I don't know, but this would be absolutely obvious to do! This
*is* the
way to determine if the neutrino mass is cosmologically
significant or
not - hence if Lerner claims that the SN observations showed
that the
neutrinos don't have such a mass, then he *must* have used this
formula.

Lerner never discussed 'cosmological significance.'

Well, he discussed if they are able to "fill up the universe". That's
the same formula.

No, it's not.

If one wants to determine what contribution to the
mass of the universe the neutrinos make, one *has* to use this formula.
It's the standard one.

Maybe he used a "non-standard" one. It's still a moot point.

And we don't know what formula he used.

If he used any other formula, he didn't use the Big Bang Theory - and
thus he couldn't claim that the SN measurements ruled out the
possibility that the neutrinos could make up the missing mass in the
BBT.

Horsefeathers.

He may have had a different constant than you provided.

What constant? The 91.5eV? This constant follows from straightforward
calculations; and, as I explained elsewhere, this formula was very
well-known in 1990 (it was proposed first in 1966!).

And other constants show from other calculations. What's your point?

We don't know what value for neutrino mass that he used (or
referenced).

Well, if I would make such pronouncements, I would use an accepted value
for the neutrino mass bounds - in other words, I would use a mass from a
review article. If Lerner didn't do this, that's just incompetence on
his side.

LOL! Just like Ned Turner's incompetence for 5eV?

We don't know what equation he used (or referenced).

See above.


So there's no *must* about it.

He *must* have used this - because otherwise, his whole claim makes
little sense. Using non-established values or formulas in order to claim
that some measurements are a problem for the BBT wouldn't make much
sense.

Lerner's claim is fine. Ned Wright misrepresented Lerner's claim -- as you
have admitted. Ned Wright did not use the argument you've used -- 13 years
after TBBNH was written.


(which both were known *BEFORE* 1991,
when Lerner published his book!),

My apologies for the confusion on publication date (the
copyright
is given as 1991). The month of the year did not matter,
prior to your proffering of a
December 1990 paper and a book published in 1990.

According to the preface of TBBNH, the first edition was
published in "late
1990," a "year and a half" before the completion of the
preface (written for a
different publisher) in "May, 1992." So the first paper was
undoubtedly published AFTER TBBNH was printed.

Well, the paper of Loredo and Lamb mentioned above, from which
the this
review article took the value of 23 eV, was published in 1989.

Now a moot point. But I still would like to know the month in
1990 when the Kolb book was published? Did it also come up in
December (i.e. post-TBBNH)?

The book itself gives only the publication year, but there is a
stamp in it which says that the library here bought it in February of
1990; hence it must have been published very early in 1990.

Thanks. Now it would be nice to find a 1990 or earlier book that performed
the calculation that you claim is "necessary."

we get:
\Omega_{\nu} 0.39.
Obviously, a value of 0.39 *IS* quite significant
cosmologically!

And using Ned's value of 5 (calculated in 2000), we get a
value of .39 (5/23) = .08.

Which still would be significant.

Now a moot point.

Right, Wright's numbers aren't demolishing to Lerner's claims. However,
the numbers in the review article *are* (because 0.35*3 1).

Ned Wright misrepresented Lerner's arugments. That's the point of
discussion.

The "* 3" exists in none of those references.

Hence, contrary to Lerner's claims, the supernova
observations did *not*
rule out a mass for the neutrino which would have been
cosmologically
relevant. Lerner is wrong there, live with it.

And now we return to what Lerner actually claimed in TBBNH.
Lerner did not make any claims about neutrino mass that was
'cosmologically interesting' or 'cosmologially relevant.'

I repeat the quotes you gave from Lerner's book here (with
slight spelling corrections, and some added comments):

And I will bypass commenting on your individual comments until
you are through.

"Cosmologists weren't perturbed, though, because particle
theorists had
provided an entire zoo of particles to make up the missing
mass."

Lerner insinuates here that these particles were all made up
only
because of the problem of missing mass, which is quite wrong.
Lots of
these particles were theoretical predictions which weren't in
the least
based on the fact that there was apparently missing mass in the
universe.

"First came heavy neutrinos."

I very much doubt that these came first. IIRC, they were one of
several parallel proposals.

"Neutrinos are real particles, observed in laboratory
experiments, but
they are quite hard to detect because they interact so little
with
matter. They appear to travel at the speed of light, so must
have no mass."

Jumping to conclusions. From "appear to travel at the speed of
light"
does not follow "must have no mass" - only "must have at most a
mass of
x eV/c^2", where x is a number which can be calculated from the
sensitivity of the velocity measurements.

"However, particle theorists postulated that neutrinos do have
mass,"

Well, that postulate wasn't a big deal. Yes, the Standard Model
at that
time treated the neutrinos as massless - but there was no
theoretical
reason at all why they really should be massless; the SM mainly
treated
them as massless because it was already known that their masses
must be
very low and hence are negligible for most effects.

"and some cosmologists decided that these massive neutrinos
could be the missing mass."

Right, some, not all. Others made other proposals. Sounds a bit
contradictory to "Cosmologists weren't perturbed, though,
because
particle theorists had provided an entire zoo of particles to
make up
the missing mass. First came heavy neutrinos.", IMO.

"A supernova blew away this idea."

Lerner is partly right: the supernova blew away the idea that
the
*electron* neutrinos could provide *all* of the missing mass.
Nevertheless, he conveniently never mentions that the SN
measurements
were not able to place constraints on the *other* neutrino
masses - and
that the SN therefore did *not* blew away the idea that *all*
of the
neutrinos could perhaps provide *all* of the missing mass.

"Supernovas produce large quantities of neutrinos when they
explode. In
1987, when a supernova occurred in the
Large Magellanic Cloud, a satellite galaxy of our own Milky
Way,
scientists were able to detect the neutrinos released, using
the same
arrays that had been patiently waiting for a decaying proton.
The
neutrinos all arrived in a single bunch, showing that they all
travel at the speed of light"

Again, jumping to conclusions.

"and have
either no mass or so little that they couldn't fill up the
universe."

Well, the measurements showed that the *electron* neutrinos
couldn't
"fill up" more than about 0.39 of the universe (very strange
wording
here!). They didn't show anything about the other neutrinos.
Lerner conveniently doesn't mention this.

And my apologies for allowing myself to get sucked into Ned
Wright's diversionary strawman definition of 'interesting
mass.'

I think the greater problem here is that Lerner pretends that
looking at
measurements of the mass of the electron neutrinos is enough to
rule *all* of the neutrinos out as being able to "fill up the
universe".

So, you prefer dishonesty to imprecision?

No. But in contrast to you, I consider Lerner's wording to be dishonest,
and Wright's comments to be imprecise, not the other way round.

On that we disagree. Wright explicitly reworded Lerner's point -- solely to
make it easier to attack. But that's only "imprecise". Lerner mentioned
one of several reasons the theory was discarded -- as you admit. But that's
"dishonest", to you, because there were other reasons, too.

If Ned thought there was a problem with focusing on "electron
neutrinos", he could have said so.

Err, he did. Quote (from your original post, where you quoted what
Wright wrote):
"Lerner claims that the neutrinos from SN 1987A in the LMC rule out an
interesting neutrino mass, but the light water detectors used can
essentially only detect electron antineutrinos, so the mu and
tau neutrinos can have plenty of mass."

Ah, you are correct. But he provided no mathematical detail.

There then would have been no need to distort Lerner's
statement.

Wright did both things: He mentioned that there is a problem with
Lerner's argument, because they only concern electron neutrinos, and
then he did make a calculation, where he unfortunately distorted
Lerner's view a bit. (come on, "cosmologically significant" and "filling
up the universe" are not sooo much different!)

Sure they are. They are the difference between a few percent and 100
percent. One to two orders of magnitude.

So I conclude that your own, personal view about the possible
role of mu and tau neutrinos was not shared by Ned Wright.

Wrong. See the quote above. Which you yourself provided in your original
post.

Yep. Still no support for Wright's claim that Lerner's "Math" was in error.

And that he knew
5 eV was insufficient to 'fill up' the universe to omega = 1.0.
So he distorted Lerner's claim, to make it attackable.

I would rather think that he tried to clarify what he was talking about.
Contrary to what Lerner claims, even low masses for the neutrinos aren't
so much of a problem, because there are lots of other theoretical
proposals for dark matter (which weren't all only made up because the
BBT "needs" dark matter, BTW).

Hello? That was Lerner's point. That neutrinos were only the first in a
long line of attempts to fill the universe. That's another reason that
Wright's savaging of Lerner was silly.

Hence it is sufficient to discuss if the
SN measurements were able to detect a "cosmologically interesting" value
of the electron mass; it isn't necessary to discuss if the electron
neutrinos alone could "fill up the universe".

LOL!

Yes, Wright's argument doesn't attack Lerner's argument directly, and
somehow distorts it - but I don't think that this is much of a problem,
if one views these arguments in their context!

The context is that the CDM universe was dead. SN 1987a was one of the
things that killed it. Neutrinos were "too light" and remain too light.

What Lerner actually *wrote* begins on p 157 of TBBNH. He is
discussing the genesis of the 'inflationary' Big Bang model
--
and the cosmologists' desire for a value of omega of 1.0.

Well, this value was measured, hence speaking of a "desire"
makes little sense.

ROTFLMAO!! Omega = 1.0 has NEVER been measured!!!!

Well, that depends on how you define "measured". This value obviously
wasn't measured *directly*; it was determined from fits of theoretical
models to the measured data - as in most of physics.
Do you have a problem with such methods?

LOL!

What is crucial here is that several independet set of data lead to fits
with Omega parameters which agree with each other (within there error
bounds). *I* would call this "Omega = 1.0" was (approximately,
obviously, no measurement is ever exact) measured.

That's what the whole issue of "dark matter" is about!!!!

No, it isn't.

Look at the reference (Peebles) given by Ned Wright! Table 20.1.

I know quite well what "Dark Matter" is about, thank you. I took several
courses here at the university about cosmology, and I've looked at
current research articles, for examples the ones listed at
http://map.gsfc.nasa.gov/m_mm/pub_papers/firstyear.html.

LOL! I'm sorry. But this post is terribly long as it is. And I can't
continue when dealing with such obvious bias.

{snip the rest}

greywolf42
ubi dubium ibi libertas

Bjoern Feuerbacher wrote in
message ...
greywolf42 wrote:

Joseph Lazio wrote in message
...
"g" == greywolf42 writes:
[regarding what was known from astronomical measurements regarding the
mass of the (electron) neutrino about 1990]

g First, here is yet another 'value' of the upper limit -- 15 eV.
g Obviously, there was only one event, and there was only one set of
g data to be analysed -- in 1987. If you pick and choose your
g analyses to find the largest number, you can come up with an upper
g limit that barely makes up 'enough' neutrino mass to make up the
g 'missing mass.' So far in this thread, we've seen contemporary
g references of 23 and 15 -- and Ned Wright's estimate of 5 eV. All
g from the same data. And all marginal, at best.

For other readers of the newsgroup, it might be worth pointing out two
facts. First, the Standard Model of particle physics (at the time)
expected that the mass of the electron neutrino (and the other two
neutrino species) would be 0 eV, so any value is significant (though
perhaps not cosmologically).

Yep. And as no value had been measured, so there was no reason to
'expect'
it to be non-zero. Certainly not in the 5 eV range.

Err, the reason to suspect that neutrino have mass is that all of the
other elementary fermions have mass - why should the neutrinos be an
exception? That would be rather unnatural.

Probably because it was first postulated long before the SM was developed.

Second, one must understand that many measurements in astronomy are
not made to the 50th decimal point, as in some branches of
experimental astronomy. As an initial measurement (or upper bound) on
the electron neutrino mass 5 eV ~ 15 eV ~ 23 eV. These various
estimates are all within a factor of 4 of each other, not so bad for
an initial measurement given the uncertainties and the fact that we
don't control the supernova explosion.

But none of them were in any way measurements of mass. All were simply
the
maximum that could not be ruled out -- even when ignoring the physical
nature of the supernova.

Giving an upper bound on the mass *is* a measurement of mass.

No, it is not. Especially since you have to ignore the emission pulse width
to get to it.

greywolf42
ubi dubium ibi libertas