Continuing the conversation with
Ken G, in particular:
Intro (
Nereid comes late to the party)
kitchen sink fishing nets (KG's ideas briefly expounded)
my confusion (request for explanation through examples)
KG's clarification#1 (complete and completed simulations; simulations in the observation process vs the guts of simulations to explain observations)
me groping towards understanding, request for a specific example (clarification re simulation in observation)
part2, my playback for confirmation (and some tidying up)
KG's specific example (M-L relationship in stars; also some tidying up).
So, second playback, to see if I've got it better ...
* the intricacies etc of what observers do are not part of what makes KG go home unsatisfied from various (AAS?) meetings
* neither is stuff where the physics is not really known, or not really understood; for example much (most?) of cosmology, work on CDM, AGNs (SMBH, accretion disks, jets, etc).
But now I'm stuck, again.
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Originally Posted by Ken G (on my SMBH example)
Quote:
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Originally Posted by Nereid
Perhaps simulations of the SgrA* SMBH and its accretion disk? or of SMBH accretion disks in general?
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Yes, that's more what I have in mind.
Quote:
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If so, then I doubt anyone would say that the simulations are complete, or completed ... the results serve mainly to show how little is actually understood and as pointers to which of the myriad things not yet considered needs to be worked on next.
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But the problem is the "completeness" of the simulation invariable rests on whether or not it agrees with the observations, rather than on how much we have learned from it. This is my point. I have seen many examples of the types of simulations that say, in effect, "here's what we got that agrees with observations, and here's the part that shows some discrepancies. We're working of finding modifications to the physics that will bring the discrepancies into line as well." As if the work was needed in the area of the discrepancies! I would instead say the more immediate need for work is in the area of the agreement-- for there we actually have the potential to make theoretical progress in understanding what we are looking at.
But this is not what you usually find, generally the observers and theorists seem to simply crave some level of reassurance that theory can recover the observations, and simply substitute the cartoons when anyone asks them why. Then they move on to the next problem! I see a huge hole there, around the question, "what is really going on there, and how can we understand it in a better-than-cartoon way without simply referring to the full simulation?" To me, stopping short of that is like saying, "I don't know but my computer does, so that's good enough".
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I'm sure that some of this can be applied to the combined work being done on SMBH+accretion disks+jets+feeding mechanisms+..., but I feel your description simply does not fit most work here.
Is this an area you are sufficiently familiar with that you could comment on it? If so, how do you think it differs (if at all) from the M-L relationship in stars example you gave?
(you guessed right: I couldn't relate closely enough to your stellar models example to make much more than superficial comments).
On the M-L example, though, here's one superficial comment: to what extent are you saying that the theoretical models (kitchen sink and all) are weak because a bunch of 'sanity checks' or 'existence proofs' are missing (or wrong)?