The moving system is not an inertial frame in 1905 Relativity
in [Relativity]
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From: valls on 2 Jul 2010 07:07 On 1 jul, 10:25, PD <thedraperfam...(a)gmail.com> wrote: > On Jun 30, 3:31 pm, va...(a)icmf.inf.cu wrote: > > > > > > > On 30 jun, 15:13, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > > > > va...(a)icmf.inf.cu says... > > > > >In a recent thread we established that > > > > Centre of mass inertial frames are the unique ones in 1905 > > > >Relativity > > > > There is nothing in the development of relativity that in any > > > way depends on a frame being defined by a center of mass. That's > > > completely barking up the wrong tree. > > > > -- > > > Daryl McCullough > > > Ithaca, NY > > > I will answer you with the same initial post of the referred thread: > > [Let be any body set with a material point modelling each one. If we > > want to describe the movements of the bodies in an inertial frame, we > > have a unique alternative: to use the centre of mass inertial frame > > corresponding to that body set. Once the Newtons absolute frame is > > rejected by 1905 Einstein (and then rejected also all the others > > moving with any uniform velocity with respect to it), remain only the > > bodies themselves to determine inertial frames.] > > Explain to us how can you determine an inertial frame once the > > absolute Newtonian one is rejected by 1905 Einstein(and with it all > > the others imaginary derived ones with all possible uniform velocities > > with respect to it). > > > RVHG (Rafael Valls Hidalgo-Gato) > > Inertial frames are *defined* by the fact that the laws of dynamics > retain their form in such frames. The center of mass frame of a system > of mutually interacting bodies is such an inertial frame (provided > that there is no measurably significant interaction with bodies > external to this system), but it is also true that ANY OTHER FRAME > moving at constant velocity with respect to the center of mass frame > also satisfies this requirement. > If you have TWO inertial frames (real massive ones, not the imaginary massless ones rejected by 1905 Einstein), then they can't be never moving at a uniform velocity one with respect to the other (at least some gravitational attraction must be present always). As a result, you must consider the centre of mass inertial frame corresponding to all the bodies involved. For ANY body set, you have always a UNIQUE centre of mass inertial frame. I accepted the definition of inertial frame that you refer. Physics laws must be always the same in all inertial frames. But I don't accept that and entity moving at a uniform velocity with respect to some inertial frame is also an inertial frame (at least not a real existing one). Only a non-massive entity can fulfil that requirement, being then one of the imaginary inertial frames already rejected by 1905 Einstein. RVHG (Rafael Valls Hidalgo-Gato)
From: valls on 2 Jul 2010 07:22 On 1 jul, 20:44, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > va...(a)icmf.inf.cu says... > > >On 1 jul, 06:58, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > >You don't consider a rigid body a massive one? > >The essential contribution of 1905 Einstein is precisely the rejection of all > >Newtonian non-massive inertial frames > > You are confused. In the respect of what is involved in an inertial > frame, there is no difference between Special Relativity and Newtonian > physics. In both cases, an inertial frame is a set of comoving unaccelerated > comoving points such that any of the points has zero relative velocity. > > -- > Daryl McCullough > Ithaca, NY I am considering in this thread only 1905 Relativity. Refer the 1905 text defining an inertial frame in the way you do. For 1905 Einstein a stationary system is one in which the equations of Newtonian mechanics hold good. In the example at the end of paragraph 4 in the 30Jun1905 paper, the rotating Earth is the stationary system (corresponding to what today is denoted GPS ECI). The ECI is a centre of mass inertial system, the unique ones in 1905 Relativity once the absolute frame (and derived ones moving with all possible uniform velocities with respect to it) is rejected by 1905 Einstein. RVHG (Rafael Valls Hidalgo-Gato)
From: Daryl McCullough on 2 Jul 2010 07:29 valls(a)icmf.inf.cu says... > >On 1 jul, 20:44, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: >> You are confused. In the respect of what is involved in an inertial >> frame, there is no difference between Special Relativity and Newtonian >> physics. In both cases, an inertial frame is a set of comoving unaccelerated >> comoving points such that any of the points has zero relative velocity. >I am considering in this thread only 1905 Relativity. You would be much better off trying to understand relativity, instead of treating it like a sacred text. Don't use Einstein's paper, use a more modern treatment. The rotating Earth is *not* an inertial frame for the purposes of Special Relativity. -- Daryl McCullough Ithaca, NY
From: Daryl McCullough on 2 Jul 2010 07:33 valls(a)icmf.inf.cu says... >Then, following you, the clock at the equator with a gravitational >centripetal acceleration in a circular path is an inertial system. No, it's not. >More probably you will remain silent about it. And don't forget >that 1905 Relativity has a huge experimental evidence with today GPS, >putting out of any doubt that 1905 Relativity formulas apply to >non-inertial frames like the clock at the equator. GPS systems use General Relativity, not Special Relativity. The Earth is *not* an inertial system (although for some experiments, it might be close enough). -- Daryl McCullough Ithaca, NY
From: Inertial on 2 Jul 2010 09:29
wrote in message news:e0108dc3-f605-4c43-a120-135314d0b976(a)b29g2000vbl.googlegroups.com... > >On 1 jul, 18:24, "whoever" <whoe...(a)whereever.com> wrote: >> wrote in >> messagenews:de60355e-94d5-4c19-aafc-35ab61249fc7(a)y4g2000yqy.googlegroups.com... >> >> >On 1 jul, 08:21, artful <artful...(a)hotmail.com> wrote: >> >> No .. know all that .. point particles are pretty basic. At least >> >> you've >> >> said something that makes grammatical sense >> >> >Don't confuse point particle with material point. Our whole Solar >> >System is modelled by a material point to describe its movement in the >> >Galaxy. The Earth-Moon system is modelled by a material point to >> >describe the ecliptic. >> >> Difference without distinction .. a piont particle is a mathematical >> abstraction where an object is able to be represented by a single point >> when >> modelling it .. that point may or may not correspond to some material (eg >> a >> system of two objects orbitting each other could be represented in a >> larger >> system by the point about which they orbit, and that point doesn't >> correspond to any material object. How is that different from a >> 'material' >> point .. and how is 'material' point in any way a better notion? >> >> --- news://freenews.netfront.net/ - complaints: n...(a)netfront.net --- > >Pluto an Charon centre of mass as a material point is modelling both >bodies as a unique entity. An the trajectory of this material point >around the Sun is the historical Pluto orbit. Is that sufficient to >you? You did not answer my questions at all so it is nowhere near sufficient for me. Try again |