let a(t) be a regular curve which lies on the unit sphere in R^3(adsbygoogle = window.adsbygoogle || []).push({});

a(t) . a(t) = 1 for all t

i want to show that the geodesic torsion Tg(t) vanishes for such a curve.

i can use the fact that a(t) can be interpreted as a unit normal N(t) to the surface along he curve.

can anyone help me with this question? thanks

my solution:

i couldnt understand how Tg(t) torsion is related to this question. I didnt know how to relate it to it

but i was thinking if a(t) is a regular curve then its Xu x Xv /= 0. and unit normal would be Xu x Xv / ||Xu x Xv|| , bot i cant understand how i would relate this to geodesic torsion?

any help?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Geodesic torsion

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**