On an Observation of M. Riesz
On a recent visit to Toronto, Professor Riesz made an interesting remark on the invariance of a certain cross-ratio, I wish to present a simple proof of his result.Let x = ( x1, x2, x3, x4), … denote homogeneous coordinates in real projective three-space; x(t), … are differentiable curves in that space.
Keyword(s):
Keyword(s):
1984 ◽
Vol 18
(1)
◽
pp. 26-26
◽
2013 ◽
Vol 36
(1-2)
◽
pp. 165-170
◽
Keyword(s):