- #1
bres gres
- 18
- 1
- TL;DR Summary
- https://www.youtube.com/watch?v=oQZTYt_Pxcc&list=PLJHszsWbB6hpk5h8lSfBkVrpjsqvUGTCx&index=28
i found there is one problem in the derivation of this volume form in 18:10.
In this derivation,i am not sure why the second derivative of the vector ## S_j '' ## is equal to ## R^{u_j}{}_{xyz} s^y_j v^z y^x##
could anyone explain this bit to me
thank you
it seems ## S_j '' ## is just the "ordinary derivative" part but it is not actually equal to ## R^{u_j}{}_{xyz} s^y_j v^z y^x##
for example: ## d^2(y^i e_i )/dx^2## is not equal to ##d^2(y^i)/dx^2 e^i##
here ## S_j '' ## is just "d(S_j)^2/ dx^2 "" (which is the change of the vector component)without considering the change of the basis vector /connection tensor.
the ##S_j'' ## here is only part of ## R^{u_j}{}_{xyz} s^y_j v^z y^x## ??
The convariant derivative of an input is equal to the normal-type ordinary derivative in scalar function only ,however in the "second covariant derivative" of a vector they are not equal
the scalar s is just the component of the vector s which is the "part of the story"
i can't see why the left side is equal to the right side since they ignore the basis vector
could anyone explain to me
thank you
could anyone explain this bit to me
thank you
it seems ## S_j '' ## is just the "ordinary derivative" part but it is not actually equal to ## R^{u_j}{}_{xyz} s^y_j v^z y^x##
for example: ## d^2(y^i e_i )/dx^2## is not equal to ##d^2(y^i)/dx^2 e^i##
here ## S_j '' ## is just "d(S_j)^2/ dx^2 "" (which is the change of the vector component)without considering the change of the basis vector /connection tensor.
the ##S_j'' ## here is only part of ## R^{u_j}{}_{xyz} s^y_j v^z y^x## ??
The convariant derivative of an input is equal to the normal-type ordinary derivative in scalar function only ,however in the "second covariant derivative" of a vector they are not equal
the scalar s is just the component of the vector s which is the "part of the story"
i can't see why the left side is equal to the right side since they ignore the basis vector
could anyone explain to me
thank you
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