Any surface bounded by the same curve in Stokes' theorem

In summary, the difference in the symmetry between Stokes' theorem and Gauss' theorem lies in the unique volume that can be enclosed by a 2D surface in ##\mathbb{R}^3##, whereas a curve in the same space can enclose multiple surfaces. This is due to the fact that in ##\mathbb{R}^3##, a 2D surface can only enclose one unique volume, while in higher dimensions, there can be multiple volumes enclosed by the same surface. The general Stokes formula is not affected by the dimensionality of the space and is symmetric.
  • #1
feynman1
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In Stokes' theorem, the closed line integral of f=the surface integral of curl f on ANY surface bounded by the same curve. But in Gauss' theorem, the surface integral of f on a surface=the volume integral of div f on a unique volume bounded by the surface. A surface can only enclose 1 volume whereas a curve can enclose many surfaces. So why is the asymmetry?
 
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  • #2
it is because in ##\mathbb{R}^3## if a 2D surface bounds some volume then this volume is unique. It is just a feature of ##\mathbb{R}^3##. The general Stokes formula ##\int_{\partial M}\omega=\int_Md\omega## is symmetric. And the manifold ##M## is not obliged to be embedded anywhere
 
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  • #3
wrobel said:
it is because in ##\mathbb{R}^3## if a 2D surface bounds some volume then this volume is unique. It is just a feature of ##\mathbb{R}^3##. The general Stokes formula ##\int_{\partial M}\omega=\int_Md\omega## is symmetric. And the manifold ##M## is not obliged to be embedded anywhere
I'm curious on this property of ##\mathbb R ^3##. Do you mean that its homology is trivial?
 
  • #4
wrobel said:
it is because in ##\mathbb{R}^3## if a 2D surface bounds some volume then this volume is unique. It is just a feature of ##\mathbb{R}^3##. The general Stokes formula ##\int_{\partial M}\omega=\int_Md\omega## is symmetric. And the manifold ##M## is not obliged to be embedded anywhere
Could you please explain why this asymmetry (1D-2D and 2D-3D) is in the language of calculus or on a similar level?
 
  • #5
feynman1 said:
Could you please explain why this asymmetry (1D-2D and 2D-3D) is in the language of calculus or on a similar level?
If you live in 2d world there only one 2d-volume is contained inside a loop of a closed curve. But if you exit in 3d then you see that there are a lot of two dimensional films pulled up on this curve. The same if you come out from ##\mathbb{R}^3## to ##\mathbb{R}^4##. The general Stokes formula does not care in which ##\mathbb{R}^m## you live and which metric you use to consider vectors instead of differential forms. Have a patience it will be explained in more advanced courses later
 
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  • #6
wrobel said:
If you live in 2d world there only one 2d-volume is contained inside a loop of a closed curve. But if you exit in 3d then you see that there are a lot of two dimensional films pulled up on this curve. The same if you come out from ##\mathbb{R}^3## to ##\mathbb{R}^4##. The general Stokes formula does not care in which ##\mathbb{R}^m## you live and which metric you use to consider vectors instead of differential forms. Have a patience it will be explained in more advanced courses later
I can think of only 1 possibility where a 2d surface can enclose multiple 3d volumes: the 3d volume inside or that outside (cavity). Does that count as an analogue of 1d curve enclosing multiple 2d surfaces?
 
  • #7
The question has been answered.
 

1. What is Stokes' theorem?

Stokes' theorem is a fundamental theorem in vector calculus that relates the surface integral of a vector field over a surface to the line integral of the same vector field along the boundary of the surface.

2. What is meant by "any surface bounded by the same curve" in Stokes' theorem?

This phrase refers to the fact that the surface and its boundary curve must have the same orientation for Stokes' theorem to hold. In other words, the surface must be "closed" and have a continuous boundary curve.

3. What is the significance of the curve in Stokes' theorem?

The curve in Stokes' theorem represents the boundary of the surface over which the vector field is being integrated. This curve is often referred to as a "closed curve" or a "closed loop."

4. How is Stokes' theorem used in physics?

Stokes' theorem is used in physics to calculate the work done by a conservative force on an object moving along a closed path. It is also used in fluid mechanics to calculate the circulation of a fluid around a closed loop.

5. Can Stokes' theorem be applied to any surface?

Stokes' theorem can be applied to any smooth surface with a continuous boundary curve, as long as the surface and curve have the same orientation. This includes surfaces such as spheres, cubes, and cylinders.

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