Cosmic acceleration rediscovered

Bjoern Feuerbacher wrote in message
...
greywolf42 wrote:
Joseph Lazio wrote in message
...

"g" == greywolf42 writes:

g Joseph Lazio wrote in message
g ...

[snip]

g If you feed such algorithms random noise, the will still provide
g you with an appearance of a signal.

I'm sure some algorithms can fail in that manner. There are many
algorithms in signal processing, though. I can think of some simple
cases where your statement is easily false.

I don't know of any that don't produce false signals. They all are
designed to enchance slight deviations. However, I do know that the
algorithms used in WMAP, for example, are false-signal producers.
In discussing with Ted Bunn, we have found that the algoritms could
produce false signals.

Was this in a thread here in sci.astro?

It was the thread "size of the CMB fluctuations" in sci.astro.research and
sci.physics.research. Note that further responses to Ted's claims from
11/2/02 were blocked by the moderator, on the basis that the moderator
(Kevin Scaldeferri) didn't understand what I was talking about. (Although
Ted had no trouble understanding and discussing this.)

Because you ask, I will post the 'disallowed' post on this newsgroup.

But
since WMAP assumes there *are* signals, then Ted figured it doesn't
matter. Which is called circular logic.

And you simply conveniently ignore that the signals found by
WMAP are nicely consistent with those found by COBE?

There are no such observations.

[snip]

{snip higher levels}

You don't specify the kind of random noise to which you're referring,
but, yes, random noise can have a mean. Perhaps the most basic is the
normal distribution, which is specified completely by its mean and
variance.

So? Without a better specified problem, your objection is somewhat
meaningless.

But I specified the problem. The signals claimed are below the physical
resolution of the detector.

Which is shown to be false by looking at the quote about
COBE.

A quote of someone else's conclusion does not support a physics position.

May I remind you again of the 7 sigma, and of
the 13 +- 4 microK?

Remind away. Now, what is the physical resolution of COBE? 1 part in
10,000. Since the MBR is about 3K, this gives a physical resolution of 300
microK (after conversion). The claim to 4 microK is pure noise.

[snip]

Conversely, if I estimate the mean and its uncertainty, find that it
is not consistent with zero, and conclude that there is a signal, what
have I done wrong?

That would depend upon how you "found" that the mean and uncertainty
were not "consistent with zero."

Err, what's your problem? A mean is non consistent with zero
if it is larger than 3 standard deviations.

Above the physical resolution of the detector.

If -- as in the case under discussion -- you
were claiming a result below the resolution of the detector -- then you
would be wrong.

The results were not below the resolution, no matter how often
you claim that.

Yet you don't mention the physical resolution of COBE. Which is 300 microK.

Bye in this thread, troll.....

{snip}

--
greywolf42
ubi dubium ibi libertas
{remove planet for return e-mail}

greywolf42 wrote:
Bjoern Feuerbacher wrote in message
...

greywolf42 wrote:

Joseph Lazio wrote in message
...


"g" == greywolf42 writes:

g Joseph Lazio wrote in message
g ...

[snip]


g If you feed such algorithms random noise, the will still provide
g you with an appearance of a signal.

I'm sure some algorithms can fail in that manner. There are many
algorithms in signal processing, though. I can think of some simple
cases where your statement is easily false.

I don't know of any that don't produce false signals. They all are
designed to enchance slight deviations. However, I do know that the
algorithms used in WMAP, for example, are false-signal producers.
In discussing with Ted Bunn, we have found that the algoritms could
produce false signals.

Was this in a thread here in sci.astro?


It was the thread "size of the CMB fluctuations" in sci.astro.research and
sci.physics.research.

Thanks, I'll try to look it up.


Note that further responses to Ted's claims from
11/2/02 were blocked by the moderator, on the basis that the moderator
(Kevin Scaldeferri) didn't understand what I was talking about. (Although
Ted had no trouble understanding and discussing this.)

If you did not notice: *many* people in the science newsgroup
often have problems understanding you. Why do you at once
jump to the conclusion that this must the their fault, not
yours?


Because you ask, I will post the 'disallowed' post on this newsgroup.

Thanks.




But
since WMAP assumes there *are* signals, then Ted figured it doesn't
matter. Which is called circular logic.

And you simply conveniently ignore that the signals found by
WMAP are nicely consistent with those found by COBE?


There are no such observations.

Let's ask it in another way: Why do the two pictures
shown for COBE and WMAP here
http://map.gsfc.nasa.gov/m_mm.html
agree so nicely with each other?



*snip*


But I specified the problem. The signals claimed are below the physical
resolution of the detector.

Which is shown to be false by looking at the quote about
COBE.


A quote of someone else's conclusion does not support a physics position.

A quote of an article discussing the analysis of the COBE
data does not support a claim that COBE was able to detect
something? Wow. Strange kind of logic here.



May I remind you again of the 7 sigma, and of
the 13 +- 4 microK?


Remind away. Now, what is the physical resolution of COBE? 1 part in
10,000.

Reference, please.

Also please note what Joseph Lazio pointed out: that if
there is enough data, it is easily possible to measure below
the physical resolution of the detector.


Since the MBR is about 3K, this gives a physical resolution of 300
microK (after conversion). The claim to 4 microK is pure noise.

Do you mean the claim to 13 microK? The 4 microK is the
estimated error.

What did they do wrong in their error analysis, in your opinion?
Have you ever read the paper and tried to find out how they
arrived at the claimed results?

Or did you never bother, because you are so utterly convinced
that it is simply not possible to obtain that data with
such an precision?



*snip repetitions*




Bye in this thread, troll.....

Fifth time.


Bye,
Bjoern