Unitary coordinate transformation = rotation?

In summary, a unitary coordinate transformation is a mathematical operation used to change the orientation and position of a coordinate system without altering the shape or size of objects within it. It is closely related to rotation, and can also include translations and reflections. Unitary transformations are a special case of general coordinate transformations and have various applications in physics, engineering, and computer graphics.
  • #1
Pacopag
197
4

Homework Statement


Suppose I define a linear coordinate transformation that I can describe with a matrix U.
If U is unitary. i.e.
[tex]U^{-1}U = UU^{-1}=1[/tex]
does that necessarily imply that the transformation corresponds to a pure rotation (plus maybe a translation), so that I may assume that volumes are invariant?


Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org
  • #2
Yes, volumes are invariant, certainly. The jacobian is 1. There are no translations if the transformation is linear. There could be reflections.
 
  • #3
Thank you.
 

1. What is a unitary coordinate transformation?

A unitary coordinate transformation is a mathematical operation that changes the orientation and position of a coordinate system without changing the shape or size of the objects within that system. It is often used in physics and engineering to simplify complex systems and calculations.

2. How is a unitary coordinate transformation related to rotation?

A unitary coordinate transformation is equivalent to a rotation if the transformation matrix is unitary and has a determinant of 1. This means that the transformation preserves the lengths and angles of vectors, resulting in a pure rotation of the coordinate system.

3. Can unitary coordinate transformations only be used for rotations?

No, unitary coordinate transformations can also include translations and reflections. However, if the transformation matrix is unitary and has a determinant of 1, it will result in a pure rotation.

4. How is a unitary coordinate transformation different from a general coordinate transformation?

A unitary coordinate transformation is a special case of a general coordinate transformation. In a unitary transformation, the transformation matrix is unitary and has a determinant of 1, whereas in a general transformation, the matrix can have any values. Additionally, a unitary transformation preserves lengths and angles, while a general transformation does not necessarily do so.

5. What are some applications of unitary coordinate transformations?

Unitary coordinate transformations have various applications in physics and engineering, such as in quantum mechanics, electromagnetism, and fluid mechanics. They are also used in computer graphics and animation to rotate and transform objects in a virtual space. In addition, unitary transformations are essential in the study of symmetry and conservation laws in physics.

Similar threads

  • Calculus and Beyond Homework Help
Replies
1
Views
774
  • Linear and Abstract Algebra
Replies
20
Views
961
Replies
1
Views
709
  • Special and General Relativity
Replies
5
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
1K
Replies
40
Views
2K
  • Nuclear Engineering
Replies
1
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
961
  • Calculus and Beyond Homework Help
Replies
1
Views
2K
Back
Top