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cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.Ok, indeed. My point was to stress the notion of parallel and FW transport: assign a curve C, a point P on it and a vector V at P (i.e... -
cianfa72 reacted to PAllen's post in the thread Undergrad Physical Interpretation of Frame Field with
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So, FW transport along any curve will preserve all of these properties. Parallel transport will only preserve them along a geodesic. For... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.Yes, of course. I'm not asking about specific properties of frame field. I'm asking about the simple case of FW transport of a set of... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.No. Given any curve C, a point P on it and a vector V at P one can solve the first-order differential equation for the parallel... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.Ah ok, maybe I wasn't very clear in post #22. In the general case (not geodesic curve) for both parallel and FW transport we need to... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.I think the same is true for parallel transport since it is defined for any curve including non-geodesic ones. However I never said... -
cianfa72 reacted to PAllen's post in the thread Undergrad Physical Interpretation of Frame Field with
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But that operation is typically called the exponential map (and is a completely rigorous construct)... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.Ok yes. Yes, however the curve C is known (it is the observer's worldline) hence the tangent vector ##\mathbf u## along the curve... -
cianfa72 replied to the thread Undergrad Physical Interpretation of Frame Field.I'm not sure whether the following argument applies to FW transport as well. Take the parallel transport equation along a curve C from... -
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Yes. That's the only orthogonality condition we've discussed. -
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A set of points forming a one-dimensional curve. But that's because you specified the orthogonality condition. If you don't specify the... -
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Note that this "exponentiation" operation isn't really well-defined, rigorously speaking, because it treats tangent vectors as... -
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As long as it's a sufficiently small length compared with the scale of the spacetime curvature. -
cianfa72 posted the thread Undergrad Physical Interpretation of Frame Field in Special and General Relativity.Moderator's note: Spin-off from another thread due to topic change. In the second link referenced, there is a claim about a physical... -
cianfa72 reacted to lavinia's post in the thread Undergrad 2-sphere intrinsic definition by gluing disks' boundaries with
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In the category of topological spaces and homeomorphisms, one can define those manifolds which are made from gluing two disks along...