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Path: ...!2.eu.feeder.erje.net!feeder.erje.net!proxad.net!feeder1-2.proxad.net!cleanfeed2-b.proxad.net!nnrp1-1.free.fr!not-for-mail Newsgroups: sci.physics.relativity Subject: Re: E = 3/4 mc? or E = mc?? The forgotten Hassenohrl 1905 work. From: nospam@de-ster.demon.nl (J. J. Lodder) Reply-To: jjlxa31@xs4all.nl (J. J. Lodder) Date: Sat, 7 Dec 2024 12:03:24 +0100 References: <309fb33a3a66f01873fdc890e899a968@www.novabbs.com> <674BCF8E.822@ix.netcom.com> <674CCA90.3DD9@ix.netcom.com> <a89d71ab22cb1e3e279a59fe50ab5ebb@www.novabbs.com> <9f1cd556912a273a8946c77614611242@www.novabbs.com> <8a0014e4135992c8ec7bd3f2f1983164@www.novabbs.com> <d906fde3148d43d339b1663f1127216a@www.novabbs.com> <13877dcc9c6a6f2dd8056d8c05f0c661@www.novabbs.com> <a7d26012926823b22e139af8670cbbe7@www.novabbs.com> <df76d88c3e9729de443afca2c0cf99fa@www.novabbs.com> <2c831e6c7e0103c00fcebe8074fec8db@www.novabbs.com> <7d37d6e841cd1936217b21a5847fc507@www.novabbs.com> <7511bb1b9b748c76df265f91eaaa468a@www.novabbs.com> <67503f94$0$12915$426a74cc@news.free.fr> <3c8abe81804e4c5b6ced7aefae766c7d@www.novabbs.com> <6750b8d4$0$29710$426a74cc@news.free.fr> <2Ji4P.2$4s%.1@fx15.ams4> <6751f410$0$518$426a74cc@news.free.fr> <geD4P.802$qW31.662@fx07.ams4> <675357ca$0$28494$426a74cc@news.free.fr> <7dde1f4c26d5621d09432295bd146ac7@www.novabbs.com> Organization: De Ster Mail-Copies-To: nobody User-Agent: MacSOUP/2.8.5 (ea919cf118) (Mac OS 10.12.6) Lines: 57 Message-ID: <67542b7b$0$5218$426a74cc@news.free.fr> NNTP-Posting-Date: 07 Dec 2024 12:03:23 CET NNTP-Posting-Host: 213.10.137.58 X-Trace: 1733569403 news-2.free.fr 5218 213.10.137.58:64171 X-Complaints-To: abuse@proxad.net Bytes: 4076 ProkaryoticCaspaseHomolog <tomyee3@gmail.com> wrote: > On Fri, 6 Dec 2024 20:00:10 +0000, J. J. Lodder wrote: > > > Finaly, you really need to get yourself out of the conceptual knot > > that you have tied yourself in. > > Something is either defined, or it can be measured. > > It can't possibly be both, > > Sure it can, provided that you use a different measurement standard > than the one used in the definition. Sure, you can be inconsistent, if you choose to be. Don't expect meaningful results. > It would not make sense to quantify hypothetical variations in the > speed of light in terms of the post-1983 meter. But they would make > sense in terms pre-1983 meters. Or (assuming some incredible ramp-up > in technology, perhaps introduced by Larry Niven-ish Outsiders) in > terms of a meter defined as the distance massless gluons travel in > 1/299,792,458 of a second. Or gravitons... :-) Completely irrelevant, and it does not get you out of your conceptual error as stated above. Summmary: There must be: 1) a length standard, 2) a frequency standard [1], and 3) c Two of the three must be defined, the third must be measured. Pre-1983 1) and 2) were defined, and 3), c was measured. Post-1983 2) and c are defined, 1) must be measured. So in 1983 we have collectively decided that any future refinement in measurement techniques will result in more accurate meter standards, not in a 'better' value for c. [2] Finally, an excercise for you personally. You quoted a pre-2018 experiment that verified that E=mc^2 to some high accuracy. (using the measured value of Planck's constant) Post-2018, Planck's constant has a defined value, and E=mc^2 is true by definition. (of the Joule and the kilogram) So E=mc^2 can no longer be verified by any possible experiment. Now: Ex1) Does this make the experiment you quoted worthless? Ex2) If not, what does that experiment demonstrate? Jan [1] Or a time standard, which amounts to the same in other words. But defining it as a frequency standard is more 'natural'. [2] Note that all this has nothing whatsoever to do with physics. (like c being 'really' constant in some sense or something like that) It is all about metrology, so about the ways -we agree upon- to have standards in the most stable, accurate, and reproducible way.