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On 07/08/2024 01:57 AM, J. J. Lodder wrote:Ross Finlayson <ross.a.finlayson@gmail.com> wrote:
>On 07/07/2024 03:39 AM, J. J. Lodder wrote:[unrelated stuff]Ross Finlayson <ross.a.finlayson@gmail.com> wrote:
>On 07/06/2024 12:56 PM, J. J. Lodder wrote:Ross Finlayson <ross.a.finlayson@gmail.com> wrote:>
>On 07/05/2024 12:00 PM, J. J. Lodder wrote:>Ross Finlayson <ross.a.finlayson@gmail.com> wrote:
>On 07/04/2024 12:29 PM, J. J. Lodder wrote:>Ross Finlayson <ross.a.finlayson@gmail.com> wrote:>
>On 06/26/2024 12:24 AM, J. J. Lodder wrote:>Ross Finlayson <ross.a.finlayson@gmail.com> wrote:>
>On 06/24/2024 11:49 PM, Thomas Heger wrote:>Am Dienstag000025, 25.06.2024 um 05:57 schrieb Tom Roberts:>
>>>Nope. YOU have imposed specific units onto the>
formula/equation. The equation itself does not impose any
particular units on its variables and constants [@], it
merely requires that they be self-consistent.
>
[@] There are many systems of units in common
use. You seem to think there is only one.
A forteriori, any result that depends on any particular
choice of units (or dimensions) is unphysical.
Yes, of course. Good point. Similarly, any result that
depends on choice of coordinates is unphysical.
>
Not quite...
>
Because velocity is 'relative' (relative in respect to what you
regard as 'stationary'), kinetic energy is frame dependent.
>
Since the used coordinate system defines 'stationary', you
need a coordinate system for kinetic energy and that for
practically everything else.
>
TH
When I hear "unphysical" I think it means "in the mathematical
representation and having no attachment to the physical
representation, in the system of units of the dimensional
analysis in the geometric setting".
>
The dimensional analysis and attachment to geometry and
arithmetic usually is about the only "physical" there is.
Dimensional analysis has nothing to do with physics. Dimensions
are man-made conventions. Nothing would change if the whole
concept had never been invented.
>(Geometry and arithmetic and the objects of analysis and so on.)>
>
Things like "negative time" and "anti-deSitter space" are
unphysical, as are the non-real parts of complex analysis,
usually, though for example if you consider the Cartanian as
essentially different from the Gaussian-Eulerian, complex
analysis, then the Majorana spinor makes an example of a
detectable observable, though, one might aver that that's its
real part, in the hypercomplex.
Well, yes, but that is another meaning of 'unphysical,
>
Jan
>
Yet, "conservation", i.e. "neither the destruction or creation",
of quantities, is exactly as according to the quantity its units.
Conservation laws do no depend on units and dimensions in any way.
>The, "dimensionless", when a usual sort of "dimensional analysis">
is the Buckingham-Pi approach, is a detachment of sorts from
the "dimensional analysis".
Yes, standard dimensional analysis,
>
Jan
>
>
Oh, here that's called 'dimensionless analysis'.
That's either an error or a silly neologism,
>
Jan
>
[Higgs irrelevancies]
>Quantities, and their derivations, have implicit units,>
about them.
'Implicit unit' is not a physical concept,
>
Jan
>[snip yet another completely unrelated article]>Also "Nessie's hump".>
>
>
So, implicits, definitely do have a physical concept attached,
and force, is a function of time.
Word salad: Yes.
Clarity about 'Implied units': No,
>
Jan
>
>
From an article the other day:
>Now I excuse me while I consider a belittling>
condescension then refrain.
And still not a word about what 'implied units' might be,
>
Jan
>
"What can't you reaD? This has been all about it."
Hmm..., not very helpful.
Force: is parameterized by time,
force is a function of time.
In Einstein's theory, "Relativity",
"Relativity" has that the Space-Time
is an differential-system of inertial-systems,
parameterized by a "the time".
So, it's implicit, and the implicits here reflect
paramterizations of functions who symbolic representations
represent algebraic quantities, and "implicit" has
its usual meaning from differential analysis.
Then, implicits like "the infinitely-many implicit
quantitiers in front of each variable in a logical
expression", gets into quantification, and, quantification.
The "usual" meaning(s).
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