Papers Published
Author's Comments:
This is a short expository paper discussing the different
notions
of equivalence, such as simple equivalence, contact
equivalence, and divergence
equivalence for variational problems with one
independent variable. I show
that the group of symmetries under one notion of
equivalence can be distinct
from the group of symmetries under another notion. I
discuss how one can
set up the equivalence problem to compute these
different groups of symmetries,
but do not enter into any actual equivalence
calculations.
Please note: This paper was typeset directly from my handwritten manuscript (nearly the last handwritten one I ever produced) and I did not get to proofread the result before it appeared. Consequently, there are many typos, particularly in the matrices on the last pages.