Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: nospam@de-ster.demon.nl (J. J. Lodder) Newsgroups: sci.physics.relativity Subject: Re: Scalar waves Date: Tue, 7 May 2024 18:42:30 +0200 Organization: De Ster Lines: 67 Message-ID: <1qt6ogf.1dzq6e9ud2kq8N%nospam@de-ster.demon.nl> References: <1qsvg5a.x7fj8618ybjpgN%nospam@de-ster.demon.nl> <8P-dna9th8kfy6v7nZ2dnZfqnPGdnZ2d@giganews.com> <1qt2y1v.1uss53m11sqhkeN%nospam@de-ster.demon.nl> <1qt4uwn.7e3e5216d5hn3N%nospam@de-ster.demon.nl> <1qt51do.9cz4pq16pvb7lN%nospam@de-ster.demon.nl> Reply-To: jjlax32@xs4all.nl (J. J. Lodder) Injection-Date: Tue, 07 May 2024 18:42:30 +0200 (CEST) Injection-Info: dont-email.me; posting-host="6e619ac58faa8905374328075b55a662"; logging-data="3538987"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+wOaLUrm3hzGlNY7esY8xBrWCRmIiBw1k=" User-Agent: MacSOUP/2.8.5 (ea919cf118) (Mac OS 10.12.6) Cancel-Lock: sha1:Ji9AOGpA1Qgiv7uL83sYjaSfwXQ= Bytes: 3940 Thomas Heger wrote: > Am Montag000006, 06.05.2024 um 13:52 schrieb J. J. Lodder: > > Mikko wrote: > > > >> On 2024-05-06 09:36:27 +0000, J. J. Lodder said: > >> > >>> A measurement is not a measurement unless it can be traced > >>> to a primary standard. > >>> So your multimeter measures 204.5 mA when it says so > >>> because the manufacturer of it says so. > >>> Your manufacturer can guarantee that, > >>> because he has calibrated the thing > >>> against his standard ampere meter. > >>> He knows that his standard meter measures amps > >>> because he takes it to his national standards lab, > >>> where they calibrate it for him. > >>> And ultimately (if you live in a small country) > >>> your national lab takes their standards to NIST, or BIPM, > >>> where they do have a primary standard. > >> > >> Possibly. Or the manufacturer or certifier or the national > >> laboratory may have a reference that they compare directly > >> to the definition. > > > > Certainly. Whatever, > > the point is and remains that a measurement isn't a measurement > > unless it can be traced to an SI standard. > > In many cases this is even required by law. > > Whatever is doing the calibrating must be a state-approved agency. > > Well, no! > > You can use any other consistent system of units, if you don't like > SI-units. Certainly, and you can use any other system of dimensions than the one that is conventionally associated with the SI. > But actually I was talking about dimensions and how those are defined. > > That term refers to WHAT is measured, while units define the quantities > of the measurement results. Sure, you can invent your own definitions, but that is not how the term 'dimension' is used in physics. > Simple example: > > you have a distance of roughly 1 meter and want to measure that. > > you could use inch, yards, forlongs, lightseconds, Angstroem, mm and the > size of the emperors feet. > > The choice of a unit would only influence the numerical value, but not > the measured distance. You forget the only length unit that is still in everyday use, the second, up to an unconvenient conversion factor. Do I really need to remind you again that the meter has been abolished as a primary standard, and that all length measurements must (by the definition of the meter) be calibrated in seconds? And yes, that includes your tape rule, Jan