If  you change coordinate systems the vectors and tensors transform in such a way that the physics is unchanged.  That's the defining property of vectors and tensors and why they are not just the arrays used to represent them.

Brent


On 9/4/2024 10:42 PM, Alan Grayson wrote:
How is the foregoing consistent with the statement that tensors are independent of coordinate systems? TY, AG

On Wednesday, September 4, 2024 at 10:39:33 PM UTC-6 Alan Grayson wrote:

    No; you never posted any page numbers in your reference. Had you
    done that, I would have immediately studied your specific
    reference. But I was about to post something like what you wrote;
    namely, that *solving* for the metric tensor *MEANS* solving for
    the 16 components defining its function, given a stress-energy
    tensor and a coordinate system. The form of the components must
    depend on the coordinates. And given a coordinate system, the
    components will vary depending on location in spacetime, and this
    is what's meant by the "metric tensor field". I thought the
    "field" refers to a *unique* *real numbe*r at each point in
    spacetime, but it must refer to the components of the matrix
    representing the tensor.  Wiki's definition seems misleading since
    it states that the metric tensor is a bilinear function of two
    vectors on the tangent plane. Those vectors are its arguments, but
    sort-of misleading. Is there anything in the foregoing that I got
    wrong? AG
    On Wednesday, September 4, 2024 at 8:09:07 PM UTC-6 Brent Meeker
    wrote:

        The metric field is the set of metric tensors, one at each
        point.  It's not some vector lengths.

        When are you gonna read "Relativity DeMystifie".  I told you
        the page numbers and you can look up more in the index.

        Brent



        On 9/4/2024 5:59 PM, Alan Grayson wrote:
        But my point is therefore that the metric tensor field is
        ambiguous !

        On Wednesday, September 4, 2024 at 6:40:38 PM UTC-6 Brent
        Meeker wrote:

            It explains this "...and yields *different *real values
            for most different pairs."

            Brent



            On 9/4/2024 1:03 PM, Alan Grayson wrote:
            and yields *different *real values for most different pairs.

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