Editing DarkMatter/VeraRubin (section)

==IAU Symposium No. 100 (1982)==

An astronomical symposium sanctioned by the International Astronomical Union (IAU) titled, ''Internal Kinematics and Dynamics of Galaxies,'' was held in Besan&ccedil;on, France, August 9 - 13, 1982.  This is the professional conference at which I presented a short "poster paper" titled, [http://adsabs.harvard.edu/abs/1983IAUS..100..205T "Stabilizing a Cold Disk with a 1/r Force Law."]. It appears as a two-page article that begins on p. 105 of the published symposium proceedings.

Dr. Rubin was (again!) the lead-off speaker for this five-day symposium; accordingly, the paper that she prepared for the symposium &#8212; titled, ''Systematics of HII Rotation Curves'' &#8212; appears as the first article (pp. 3 - 8) in the proceedings. Two pages of text (pp. 9 - 10) that immediately follow her article record six questions that were  asked of Dr. Rubin at the end of her presentation, along with her six responses.  The sixth question was from me; here is the published record:
<table border="0" align="center" width="60%"><tr><td align="left">
<font color="maroon">
TOHLINE: &nbsp; I would like to emphasize at the opening of this symposium that the often quoted ratio M/L is in fact the ratio V<sup>2</sup>r/L of the directly measurable quantities V, r and L.  This ratio V<sup>2</sup>r/L can only be interpreted as an indicator of mass to light ratio if we assume that Newton's law of gravitational attraction is correct on the scale of galaxies.  Since Keplerian behavior is essentially never seen in extra-galactic systems, I might be so bold as to suggest that the validity of Newton's law should now be seriously questioned.  I hope that observers who have definitive evidence that Keplerian behavior has been observed in any system will emphasize that evidence at this meeting.
</font>
</td></tr>
<tr><td align="left">
<font color="purple">
RUBIN: &nbsp; While we have observed that most Sa, Sb and Sc, galaxies have flat or slightly rising rotation curves, a few have slightly falling curves.  However, I know of no isolated galaxy with rotation velocities decreasing as rapidly as <math>V \propto r^{-1 / 2}</math>.  The point you raise is worth keeping in mind although I believe most of us would rather alter Newtonian gravitational theory only as a last resort.
</font>
</td></tr></table>