Re: Two Studies (was in Sizing Up the Universe)

From: Bjoern Feuerbacher (feuerbac_at_thphys.uni-heidelberg.de)
Date: 06/25/04 

Date: Fri, 25 Jun 2004 13:09:11 +0200

greywolf42 wrote:
> Bjoern Feuerbacher <feuerbac@thphys.uni-heidelberg.de> wrote in message
> news:cbbnf3$l30$1@news.urz.uni-heidelberg.de...
>
>>greywolf42 wrote:
>>
>>>Bjoern Feuerbacher <feuerbac@thphys.uni-heidelberg.de> wrote in message
>>>news:cb91e1$rup$1@news.urz.uni-heidelberg.de...
>>>
>>>
>>>>greywolf42 wrote:
>>>>
>>>>
>>>>>Bjoern Feuerbacher <feuerbac@thphys.uni-heidelberg.de> wrote in message
>>>>>news:cb706a$s6b$1@news.urz.uni-heidelberg.de...
>>>>>
>>>>>
>>>>>
>>>>>>greywolf42 wrote:
>>>>>
>>>{snip Bjoern's attempt to focus on his silly allegory about a murder}
>>
>>This was a minor part of my reply, not the "focus", and *you*
>>essentially started that by saying:
>>"After I had dealt with a series of chuckles from Bjoern in the above
>>thread,..."
>>
>>So, as usual, you misrepresent what actually happened.
>
>
> The 'murder' was the one issue out of the *prior* thread that you chose to
> focus on from the prior thread.

Well, since that was the one which caused *me* the most chuckles about you.

> Instead of the following physics topics
> that you could have chosen:
>
> "We CAN see back to within 300,000 years of the Big Bang."
> Extinction.
> Direct measures of distance.
> Indirect measures of distance.
> Transmission speed of light.
> Assumption that redshift always equates to distance.
> Linear vs. nonlinear equation of redshift vs. distance.
> Hubble vs. Wirtz' priority for the redshift / distance relation.
> Cepheids.
> Hubble's data scatter.
> The units of redshift.
> Halton Arp and his banishment for finding 'inconvenient' data.
> When to do statistical studies, and when to assume it's merely
> 'coincidence.'
> The BB's historical problem with failing to predict later observations.
> Cepheid use for the Hubble calibration.
> The lack of theoretical basis of the Tully-Fischer relation.
> Any argument used by a 'creationist' must be invalid, a priori.
> Globular cluster ages, and/or the age of the universe.
> The scientific method vs. the Ptolemaic method.
> The difference between observation and theory.
> The substance of Ptolemaic theory (as understood by historians).
> CMBR spectrum and power spectrum.

I don't think that discussing such advanced stuff with someone who says
that we can't know that a murder has happened if there are no
eyewitnesses makes much sense.

> I'll quit here. I was only about 1/2 way down.
>
> And allegorical murder was the best thing you could find in the post?

Yes, because this showed that on a very basic level, you don't
understand science.

>>>>>>What I meant was observing several
>>>>>>points, and calculating the distance from those observations by using
>>>>>>essentially a triangle. Similar to parallax methods, but in these
>>>>>>cases, the triangle points in the other direction (the base line of
>>>>>>the triangle is "out there").
>>>>>
>>>>>In the case of triangulation (of which parallax is a special case) the
>>>>>baseline is a known quantity. In the case of 'reverse' geometrical
>>>>>methods, the distance between the 'two points' is not known (only
>>>>>the angular distances on the celestial sphere are known).
>>>>
>>>>Yes, obviously.
>>>
>>>It apparently wasn't obvious to you before.
>>
>>It was. Why on earth do you think otherwise?????
>
>
> Because you not only claimed that parallax was not triangulation, but were
> rudely assertive about it.

I only said that parallax and triangulation are not *equivalent* terms.
I never said that parallax is not triangulation!!!

Would you *please* stop misrepresenting what I actually say?

>>>(You snipped your earlier
>>>insistence that the latter was 'triangulation.'
>>
>>If one can determine the base line based on some other observations,
>>the method *is* triangulation.
>
>
> No. If one can determine the baseline from first principles, it is
> triangulation.

Please tell me what these nice "first principles" are, and who judges that.

>>>>>Which makes these methods
>>>>>dependent upon some *other*, theoretical distance calculation.
>>>>
>>>>And you see a problem with that?
>>>
>>>Not at all. It simply isn't triangulation or a pure geometric distance
>>>determination.
>>
>>As soon as the distance has been determined, it *is* triangulation.
>
>
> Ummm, no.

Sorry for the misstatement. What I meant to say was "as soon as the
*baseline* has been determined, it *is* triangulation".

> The distance must be determined *by* triangulation to *be*
> triangulation. The baseline must be determined by some primary method.

Right, I agree with that. Sorry for the error above.

> (See immediately below.)
>
>
>>>>>We can't *know* the size of the baseline "out there."
>>>>
>>>>Why do you feel the need to distinguish between "know" and "accurately
>>>>determine by observations"?
>>>
>>>One is fundamental obervation. The other is theoretical calculation.
>>
>>Err, no. The baseline is *also* determined based on *observations*.
>>One doesn't see it *directly*, but the calculations are *based on
>>observations*.
>
>
> If the observations are not fundamental (as is the case in Herrnstein, et
> al),

Please tell me when an observation is "fundamental" and when it isn't,
and who judges that.

> the baseline is determined *based on* other theoretical distance
> assumptions and calculations. Yes, there *are* observations involved -- but
> these are the old Hubble terms.

Please present evidence for this assertion.

[snip repetition]

>>>Using the theological term 'know'
>>>is not useful. (Then again your theological approach probably helps you
>>>in your academic career.)
>>
>>"know" has little do to with theology.
>
>
> I consider it theological. However, I'll accept metaphysical. It is not
> part of the scientific method.

As usual, you play silly word games, I see.

>>>>>>>Geometry is claimed from "direct measurement of orbital motions in a
>>>>>>>disk of gas surrounding the nucleus of this galaxy." How many people
>>>>>>>remember a similar claim about the detection of actual motion in the
>>>>>>>Andromeda galaxy, years ago?
>>>>>>
>>>>>>a hint for you: they compare the distance measured in this way with
>>>>>>our determinations of that distance. The different results agree.
>>>>>
>>>>>I'm not a bit surprised. But how does that address the historical
>>>>>situation, above? Which also 'agreed' with (some) expected distance
>>>>>determinations.
>>>>
>>>>References, please.
>>>
>>>Do you admit to ignorance about the publication of observation of proper
>>>motions in the Andromeda galaxy?
>>
>>Yes, I admit my ignorance about this.
>
>
> Fair enough. I'll dig around and find it. (It was in the '20s, if I
> remember rightly).

Thanks.

I'll hope you will not find again an excuse for not keeping this
promise, as in the case of Beckmann's book...

>>>Or are you disputing this? Or are you simply trying to weasel?
>>
>>No. Now, why don't you simply give the references, instead of
>>again engaging in mud slinging?
>
>
> Because it will take some digging. It is a well-known historical issue in
> astronomy. Have you ever taken an astronomy course?

Yes. Astronomy was even one of the topics in my master exam (nuclear
astronomy, to be precise). But I don't remember having heard
anytime about "proper motions in the Andromeda galaxy". The only thing
about that galaxy I remember about in the moment is that it seems to
have two cores.

>>>>>>>Of course, the primary problem is that the jet angle cannot be known
>>>>>>
>>>>>>>from direct observation.
>>>>>>
>>>>>>But can be deduced from the observations in many cases.
>>>>>
>>>>>Not yet. They're still hoping to find some way to do this.
>>>>>But no one's figured out how to do this yet -- despite 30 years
>>>>>of hoping.
>>>>
>>>>Err, this directly contradicts what you quoted above:
>>>>"We have presented several techniques for measuring or usefully
>>>>constraining these parameters." "these parameters" include the jet
>>>
>>>angle.
>>>
>>>Not the 'usefully constrained' part.
>>
>>Why did you ignore the "measuring" part?
>
>
> Because they can't measure the jet angle yet.

How do you know?

[snip]

>>>>>In fact, I couldn't.
>>>>>Because there *are* no results.
>>>>
>>>>Oh, the other method of you: ignore the results.
>>>
>>>Hmmm. Must have missed them.
>>
>>They are there, in the stuff you quoted themselves.
>>
>>
>>>Could you quote the precise distances from the paper? (He said
>>>sweetly.)
>>
>>Err, we were talking about "results" here in general, not about
>>*PRECISE* distances. As usual, you simply shift the goalposts...
>
>
> LOL! Results *MUST* be specific.

"specific" and "precise" is by no means equivalent. Could you please
stop shifting the goal posts?

> The fuzzy, spin-doctor quotes about
> 'constrained' parameters is a laugher on it's own.

Oh, yes, all those scientists are totally silly and incompetent, right?

[snip repetitions]

>>>>>That always concludes with the need for more funding.
>>>>
>>>>Which in this case led to a result.
>>>
>>>The result was the call for more funds, because they still can't
>>>determine the jet angle.
>>
>>Ever heard the term "preliminary result"?
>
>
> In requests for more funding, of course.

No, not only there.

>>>>>Why did you focus on the request for more money, and ignore the (lack
>>>>>of) physics in the reference you provided?
>>>>
>>>>Pardon??? Which lack of physics are you talking about???
>>>
>>>The fact that they still can't determine jet angle.
>>
>>Why is that a lack of physics?
>
>
> Because without it they *have* no method of measuring anything substantive.

They have a method for *constraining* the distance. Why is that not physics?

[snip repetition]

>>>And without the jet angle, they are DITW.
>>
>>They are what?
>
>
> Sorry. Obviously the acronym was too arcane, or too American.

I suspect the second.

> "Dead In The Water." Extracted from naval battles. A ship that was 'dead
> in the water' was damaged so badly that the engines could not move the ship.
> It was going nowhere, and could be easily torpedoed, shelled or otherwise
> sunk. Sometimes scuttled simply because it was a liability and would put
> the other ships at risk, if they tried to tow or fix it.

Thanks for the explanation.

However, I still don't see your problem. They are at least able
to *constrain* the distance. That doesn't count as anything for you?

Bye,
Bjoern

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