Path: ...!news.misty.com!2.eu.feeder.erje.net!feeder.erje.net!fu-berlin.de!uni-berlin.de!news.dfncis.de!not-for-mail From: "Jonathan Thornburg [remove -color to reply]" Newsgroups: sci.physics.research Subject: Re: Experiments on the validity of Relativity Date: 5 Jun 2024 07:10:25 GMT Lines: 28 Approved: hees@itp.uni-frankfurt.de (sci.physics.research) Message-ID: References: X-Trace: news.dfncis.de dpADD0XaDnvk4jJW34Wq/QD+LSWtWwjiRkLXMmC3ENUzwmmCnoP4Avfsjd2/FdTuQi Cancel-Lock: sha1:tXzkzNgfPcB5TMNIEdhnLH0s10Y= sha256:Do1unTULkSG7AbSm8D5kGaBDck1RCCdV0DNNa6o0lME= Bytes: 2179 Luigi Fortunati wrote: > This is what happens to accelerometer 1 in my animation > https://www.geogebra.org/classic/vtvnm8uv where you don't notice the > contraction and stretching of the springs just because the variations > are too small to be visible. > > But just increase the force of gravity to realize that it doesn't show > zero acceleration at all. > > Look what happens to accelerometer 2 which is also in free fall in a > gravitational field: does it seem to show zero acceleration? Your animation shows the accelerometers placed in an ambient gravitational which varies significantly across the dimensions of the accelerometer. We don't expect an accelerometer to work properly in such a situation. The definition of an "ideal" accelerometer includes (among other conditions) measuring acceleration-relative-to-free-fall at a *point*, i.e., it assumes that tidal fields are negligable, i.e., it assumes that the accelerometer is small compared to the scale of variation of any ambient gravitatonal fields. Your accelerometer #2 violates this assumption. -- -- "Jonathan Thornburg [remove -color to reply]" currently on the west coast of Canada "The 'S' in 'IoT' stands for 'Security'." -- commenter on /Ars Technica/, 2024-05-16