Does This Infinitesimal Mapping Transformation Look Correct?

Click For Summary
SUMMARY

The forum discussion centers on the correctness of an infinitesimal mapping transformation involving new variables. The original mapping is defined as x^u → x^u + ξ^u(x) with u = 1,2,3,4. The user questions whether the transformation should be expressed as ξ^{'u}(x^{'}) = ∂ξ^{u}(x)/∂x^p x^{'p}(x) or as ξ^{'u}(x^{'}) = ∂x^{'u}/∂x^u ξ^{u}(x). The conclusion drawn is that the latter representation is correct, as it aligns with the linear nature of the infinitesimal transformation, which can be modeled as a matrix operation.

PREREQUISITES
  • Understanding of infinitesimal calculus
  • Familiarity with Jacobian transformations
  • Knowledge of linear algebra concepts
  • Experience with matrix operations
NEXT STEPS
  • Study the properties of Jacobian matrices in transformations
  • Learn about linear transformations in vector spaces
  • Explore applications of infinitesimal calculus in physics
  • Investigate advanced topics in differential geometry
USEFUL FOR

Mathematicians, physicists, and students studying advanced calculus or differential geometry who are interested in infinitesimal transformations and their applications.

jason12345
Messages
108
Reaction score
0
For an infinitesimal mapping with u = 1,2,3,4:

x ^u \rightarrow x^u + \xi^u(x)

Now suppose we introduce a new set of variables:

x^{'u} = x^{'u}(x)

I would have thought the infinitesimal mapping in terms of the new variables should be written as:

\xi^{'u}(x^{'}) = \frac{\partial \xi^{u}(x)}{\partial x^p} x^{'p} (x)

However, it is written as:

\xi^{'u}(x^{'}) = \frac{\partial x^{'u}}{\partial x^u} \xi^{u} (x)

Does this look correct to you?
 
Physics news on Phys.org
Hi jason12345! :smile:

The infinitesimal transformation is linear, and is essentially a matrix:

y = (I + Z)x
y' = (I + Z')x'

The coordinates of Z transform as Z' = (Jacobian)Z :wink:
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 36 ·
2
Replies
36
Views
6K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 9 ·
Replies
9
Views
5K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 30 ·
2
Replies
30
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K