What is the difference between zero-rank tensor $x$ (scalar) and vector $[x]$ in 1D?
As far as I understand tensor is anything which can be measured and different measures can be transformed into each other. That is, there are different basises for looking at one object.
Is lengthlength a scalar scalar (zero rank tensor) or is it a 1D vector (rank 1 tensor)? I think
In books it is notsaid that temperature, pressure and other "numbers" are 0rank tensors, they are invariant under transformations and posess no "direction" (that is there is no basis for them). ex But I'm cofused about units... I thinks of units as somekind of basis.
ex.:
- physical parameter: writing pen's length
- tensor: $l$
- length in inches"inches basis": $[5.511811023622]$
- length in centimeters"centimeters basis": $[14]$
- transformation law: 1cm = 2.54inch
so $l$ is a scalar (0rank), but on the other hand it's a tensor of rank 1 since "physical parameter of length is invariant, only it's measuresvector (in different units1rank) are".
The same examplelogic can be made withapplied to mutate classical exampleexamples of 0rank tensors: pressure, temperature (which is used as a primer of zero rank tensor most in any book) in C and K units. I'm confused.