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From: Han de Bruijn on 11 Sep 2006 03:15 Aluminium Holocene Holodeck Zoroaster wrote: > questioning one's own formulations at least is sufficent > for not being a crank, although the necessity of it might > not be apparent with some prodigies. > >>Is the perpetual doubt about the correctness of your own mathematical >>formulas a necessary and sufficient condition for not being a crank? > > thus: > didn't Newton post a bunch of calculations viz hollow spheres etc., > suchlike?... is it indeed thought that galaxies rotate, as if > they were solid disks, or is it more complicated?... > I actually had no definite idea as to the raison d'etre > de stuffus darkus, other than *some* rotational anamoly > of galaxies, however it was observed. _Do_ all galaxies rotate as if they were solid disks? And is it indeed the _only_ reason to assume the existence of dark matter? Han de Bruijn
From: Lester Zick on 11 Sep 2006 11:53 On Mon, 11 Sep 2006 09:15:56 +0200, Han de Bruijn <Han.deBruijn(a)DTO.TUDelft.NL> wrote: >Aluminium Holocene Holodeck Zoroaster wrote: > >> questioning one's own formulations at least is sufficent >> for not being a crank, although the necessity of it might >> not be apparent with some prodigies. >> >>>Is the perpetual doubt about the correctness of your own mathematical >>>formulas a necessary and sufficient condition for not being a crank? >> >> thus: >> didn't Newton post a bunch of calculations viz hollow spheres etc., >> suchlike?... is it indeed thought that galaxies rotate, as if >> they were solid disks, or is it more complicated?... >> I actually had no definite idea as to the raison d'etre >> de stuffus darkus, other than *some* rotational anamoly >> of galaxies, however it was observed. > >_Do_ all galaxies rotate as if they were solid disks? And is it indeed >the _only_ reason to assume the existence of dark matter? These are good questions. The documentary on dark matter that I watched gave the impression that the study of rotational velocities in Andromeda gave what is considered the first direct evidence of a rationale for dark matter in the constant distribution of velocities regardless of r by the woman who analyzed them. I believe the anomaly is that matter at varying radii rotate at a constant velocity which would mean the galaxy as a whole would not rotate as a solid disk because matter at greater r would fall behind matter at lesser r in angular terms. This is in contrast to the distribution of velocities in the solar system which fall as the inverse square of distance in proportion to the strength of gravitational attraction. And whether this is the only rationale for dark matter or not I cannot say. In any event there is a separate thread "Physicists Howl at Dark Matter" devoted to the subject where the balance of my comments appear from a couple days ago. The substance of those comments is that a disk of uniform density inverse square gravitationally attractive matter should rotate at constant velocity because the inverse square nature of the force should be more or less exactly offset by the square dependence of the amount of gravitationally attractive matter as a function of r and I'm really kind of interested in finding out what exactly the problem is. ~v~~
From: Lester Zick on 26 Sep 2006 18:31 On 26 Sep 2006 12:56:47 -0700, "Aluminium Holocene Holodeck Zoroaster" <QncyMI(a)netscape.net> wrote: >as an aside, I recently realized why it is that >British authors tend to eschew punctuation <a-hem>, >probably a matter for *philologie*. but, thanks for summarizing >from that ridiculously verbose catfight in that other item! Well I've streamlined my use of punctuation,,,, especially commas,,,, considerably in the interests of concisity. >anyway, I was referring by "proof" to the axiomatic assumption >that a galaxy is a "solid" disk, and nothing else, because Well the difficulty is that I don't adhere to axiomatic assumptions nor do I maintain that galaxies are solid disks. Solid disks are merely ideal initial assumptions to which divergences are applied. >I just don't follow your armwaving; although >it'd be nice to use Kepler's orbital constraint on the periods >of rotation "due to" gravity -- not Kepler's line o'thought -- >the reasons may lie outside of the Department of Einsteinmania, >The Musical: Considering Only Gravity! Well I rather expect we can get to the bottom of it all without the benefit of clergy and other dark matter. >> >_Do_ all galaxies rotate as if they were solid disks? And is it indeed >> >the _only_ reason to assume the existence of dark matter? >> >> These are good questions. The documentary on dark matter that I >> watched gave the impression that the study of rotational velocities in >> Andromeda gave what is considered the first direct evidence of a >> rationale for dark matter in the constant distribution of velocities >> regardless of r by the woman who analyzed them. I believe the anomaly >> is that matter at varying radii rotate at a constant velocity which >> would mean the galaxy as a whole would not rotate as a solid disk >> because matter at greater r would fall behind matter at lesser r in >> angular terms. This is in contrast to the distribution of velocities >> in the solar system which fall as the inverse square of distance in >> proportion to the strength of gravitational attraction. And whether >> this is the only rationale for dark matter or not I cannot say. >> >> In any event there is a separate thread "Physicists Howl at Dark >> Matter" devoted to the subject where the balance of my comments appear >> from a couple days ago. The substance of those comments is that a disk >> of uniform density inverse square gravitationally attractive matter >> should rotate at constant velocity because the inverse square nature >> of the force should be more or less exactly offset by the square >> dependence of the amount of gravitationally attractive matter as a >> function of r and I'm really kind of interested in finding out what >> exactly the problem is. > >thus: >monsuier Drell, >you should learn a tiny bit of physics, before >you go all-out in an effort to pile onto stringtheory >with your Team Hemingway. > >reviews of reviews of epistolary crtitiques of theoretical physics, >are just a new level of stuff that Alan Sokal didn't think of, and >could not possibly have. > >(actually, I don't know what "epistolary" means, but >I was trying to convey "dueling banjos" .-) "Epistolary" loosely translated from the English means "letter-written". You may perhaps mean "epistemological". >> The Trouble With String TheoryIt's claptrap, a new book argues. > >thus: >how about "strucurally unsound" in simple sense, >of there being no way to *balance* it, such as >in the example you give, wherein the imbalance >is quite symmetrically deployed, and arrayed >amongst many directions ... well, eight of them; >I never noticed such a configuration >on a drive wheel, though, although usually "dished." > >thus quoth: >Why is it "fatal" to have different number of spokes on each side of >the hub? Some real bicycle wheels are made this way to accomodate the >offset of the hub flanges from the center of the rim (clearance for >rear sprockets / cogs)...and to equalize spoke tension between the two >sides of the wheel. Typical is 8 spokes on the left side and 16 on the >right, many other combinations have also been done. > >thus: >so, Waht?... Earth isn't an oblate ellipsoid; isn't it "pearshaped," >and was either even a consideration of the OP? >> > I thought that transverse mercator was simply done >> > along arbitrary axis, not just the rotational one; so, >> > rhumblines should also be straightlines on one. >> On a sphere, but not on an ellipsoid. > >thus: >oops, I'd put the wrong URL in my sig, because >of the "W05" in two of them (well, >the other article is good, two). I want to quote >from the PDF -- I will!... >I discovered this construction while contemplating >a fragment from Diophantus' lost work "On Polygonal >Numbers," which describes a proposition >by the classical Greek geometer Hypsicles: > "There has also been proved what was stated >by Hypsicles in a definition, namely, that 'if >there be as many numbers as we please beginning >from 1 and increasing by the same common difference ...'" > >--it takes some to jitterbug! ~v~~
From: David R Tribble on 26 Sep 2006 18:50 Lester Zick wrote: >> Because [mathematicians] don't and probably can't demonstrate their trivial >> assumptions of truth. > David R Tribble wrote: >> Here's the first Peano axiom: >> 1. 0 is a natural number. >> >> Is it (trivially) true or false? > Lester Zick wrote: > Assumptions are always trivial. So the only question is whether the > assumption is true or false. Zero is not a natural number. If it were > it would have been discovered long before it was. Interesting proof you've got there: Since zero was not discovered until after the other natural numbers (ca. AD 1000), it cannot be a natural.
From: Lester Zick on 27 Sep 2006 12:54
On 26 Sep 2006 15:50:16 -0700, "David R Tribble" <david(a)tribble.com> wrote: >Lester Zick wrote: >>> Because [mathematicians] don't and probably can't demonstrate their trivial >>> assumptions of truth. >> > >David R Tribble wrote: >>> Here's the first Peano axiom: >>> 1. 0 is a natural number. >>> >>> Is it (trivially) true or false? >> > >Lester Zick wrote: >> Assumptions are always trivial. So the only question is whether the >> assumption is true or false. Zero is not a natural number. If it were >> it would have been discovered long before it was. > >Interesting proof you've got there: > Since zero was not discovered until after the other natural > numbers (ca. AD 1000), it cannot be a natural. There you go. My point exactly. ~v~~ |