Metric Tensor in Spherical Coordinates

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The discussion centers on the derivation of a metric tensor in spherical polar coordinates in 3-D, with specific components outlined by the user. The user expresses difficulty in finding confirmation of their derived tensor online, which includes components like g11, g12, and g33. They detail their methodology, including the differentiation of a vector and the calculation of tangential basis vectors. Upon reflection, the user acknowledges a potential mistake in their derivation process. The conversation highlights the challenges of verifying complex mathematical results in the context of spherical coordinates.
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I recently derived a matrix which I believe to be the metric tensor in spherical polar coordinates in 3-D. Here were the components of the tensor that I derived. I will show my work afterwards:

g11 = sin2(ø) + cos2(θ)

g12 = -rsin(θ)cos(θ)

g13 = rsin(ø)cos(ø)

g21 = -rsin(θ)cos(θ)

g22 = r2sin2(ø) + r2sin2(θ)

g23 = 0

g31 = rsin(ø)cos(ø)

g32 = 0

g33 = r2cos2(ø)

The above is what I derived, but when I tried to verify to see if my answer was correct by checking various websites, I did not see any site have what I derived.

Here is my work:

The axes were:

x1 = r

x2 = θ

x3 = ø

The vector that I differentiated was:

<rcos(θ)sin(ø) , rsin(θ)sin(ø) , rcos(θ)>

I then differentiated the vector with respect to the various axes in order to derive my tangential basis vectors.

Here were my basis vectors:

er = <cos(θ)sin(ø) , sin(θ)sin(ø), cos(θ)>

eθ = <-rsin(θ)sin(ø), rcos(θ)sin(ø) , -rsin(θ)>

eø = <rcos(θ)cos(ø), rsin(θ)cos(ø) , 0>

Finally, I did the dot product with these basis vectors to derive the components of my metric tensor.

That is how I got what I derived, but I don't see any confirmation of this online.

Can anyone please either verify if I am right with this metric tensor or tell me where I went wrong?
 
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space-time said:
The vector that I differentiated was:

<rcos(θ)sin(ø) , rsin(θ)sin(ø) , rcos(θ)>

The transformation to spherical polar coordinates is

x = r sin(θ) cos(ø)
y = r sin(θ) sin(ø)
z = r cos(θ)

r = <r sin(θ) cos(ø), r sin(θ) sin(ø), r cos(θ)>
 
Bill_K said:
The transformation to spherical polar coordinates is

x = r sin(θ) cos(ø)
y = r sin(θ) sin(ø)
z = r cos(θ)

r = <r sin(θ) cos(ø), r sin(θ) sin(ø), r cos(θ)>

So I made a careless mistake it seems. Thank you Bill K.
 
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