A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Inertial on 7 Mar 2010 21:48 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:1c6a2640-39f5-4ea4-9c85-127e71f4e6a2(a)33g2000yqj.googlegroups.com... > On Mar 7, 6:58 pm, "Inertial" <relativ...(a)rest.com> wrote: >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message >> >> news:4b943853$0$11336$afc38c87(a)news.optusnet.com.au... >> >> >> >> >> >> >> >> > "Inertial" <relativ...(a)rest.com> wrote in message >> >news:4b942bcf$0$27789$c3e8da3(a)news.astraweb.com... >> >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message >> >>news:4b93bf73$0$28464$afc38c87(a)news.optusnet.com.au... >> >> >>>>> 1) your statement: "For clarity, both effects are purely >> >>>>> observational - SR presumes (ideal) clock mechanisms are completely >> >>>>> unaffected by a clock's motion." -- I agree the physical mechanism >> >>>>> of >> >>>>> the clock is unaffected, but this is a really misleading statement, >> >>>>> since the amount of proper time that the clock consumes is affected >> >>>>> by >> >>>>> its motion. Are you trying to say >> >> >>>> I was "trying to say" exactly what I did say. If you didn't find it >> >>>> clear enough, try this: relative slow-downs/speed-ups observed in >> >>>> the >> >>>> readings of SR's ideal clocks aren't due to changes in the tick >> >>>> mechanisms of those clocks. >> >> >>> I still don't find it clear, as it begs the question - it says what >> >>> doesn't cause the change, not what does cause the change. >> >> >>> The standard SR answer is much more direct - the clocks slow down due >> >>> to >> >>> relativistic time dilatation from them being in different reference >> >>> frames. >> >> >>> Is that standard position of SR also your position? Or is your >> >>> somehow >> >>> different? >> >> >> SR says that the difference in clock sync (clock settings) cause the >> >> measurement of length to be contracted and measurement of clock >> >> ticking >> >> rates to be dilated. >> >> > More or less. >> >> That's what it is :) >> >> > But I asked you about *your* position, not SR's position. >> >> My position is SR's position >> >> > Do you agree that that the clocks slow down due to relativistic time >> > dilation, as predicted by SR, or not? >> >> They are measured as slower, just as a rod is measured as shorter. This >> is >> due to the difference in simultaneity. They don't slow down because a >> moving observer is looking at them any more than a rod shrinks because a >> relatively moving observer is looking at it. >> >> Here's a little example you might follow .. with time differences >> exagerated >> for clarity >> >> Here are six clocks, in tow rows (S and S'), all ticking at the correct >> rate, but set with different times... >> >> S' 10:30 11:00=A 11:30 <--v >> S 11:30=C 11:00=B 10:30 -->v >> >> Clocks B sees the A is synchronized with it. >> >> Now .. the clocks are moving in opposite directions so after an hour we >> have >> >> S' 11:30 12:00=A 12:30 >> S 12:30=C 12:00=B 11:30 >> >> Clock A has moved away from clock B .. but another clock (C) in S can see >> the time on it. Clock C sees that clock A is half an hour slow (A shows >> 12:00 when C shows 12:30). So according to the clocks in S, clock A is >> ticking slower. We also note that clock B now sees a *different* S' >> clock >> next to it as being fast (it shows 12:30 when B shows 12:00) >> >> If you look at the same scenario but from the point of view of the other >> row >> of clocks, you get symmetric results. >> >> This is how clock synch affects measured ticking rates for moving clocks >> in >> SR. Even though the clocks themselves do NOT change their intrinsic >> ticking >> rates.- Hide quoted text - > > Looks good, but let's take it one step further. The observer with > clock A jumps to frame S" which is traveling in the same direction as > S relative to S' but at twice the velocity. > > S" 1:00 12:00=A 11:00 -->2v > S' 11:30 12:00=A 12:30 <--v > S 12:30=C 12:00=B 11:30 -->v > > Clocks A and B continue to tick at there same intrinsic ticking rate > and an hour later A has overtaken B. > > S" 2:00 1:00=A 12:00 -->2v > S' 12:30 1:00=A 1:30 <--v > S 1:30=C 1:00=B 12:30 -->v > > The above provides the same situation as the twins paradox. Clock A > left clock B and returned. So why doesn't clock A show less time > elapsed than B? (Note the clocks in S" are further out of sync than > those in S due to the higher velocity.) The three clock situation cannot be so easily drawn .. bit like trying to drawing a three dimensional figure in 2d :) This sort of diagram only really works for a single pair of clocks looking from a third frame in which they move with the same speed. Things are trickier when there is frame jumping going on :):)
From: Peter Webb on 7 Mar 2010 21:52 > > LET is as possibly valid as SR .. Neither is refuted experimentally. I > just don't think it is the correct physical explanation. LET is not > compatible AFAIK with GR .. so is a bit of a dead end .. and has the > assumption of an undetectable aether with properties that don't make > sense. > The experimental support for a fixed ether in SR is comparable to the experimental support for unicorns in zoology. Lots of luck proving either exists.
From: Inertial on 7 Mar 2010 22:00 "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message news:4b946681$0$24251$afc38c87(a)news.optusnet.com.au... >> >> LET is as possibly valid as SR .. Neither is refuted experimentally. I >> just don't think it is the correct physical explanation. LET is not >> compatible AFAIK with GR .. so is a bit of a dead end .. and has the >> assumption of an undetectable aether with properties that don't make >> sense. >> > > The experimental support for a fixed ether in SR is comparable to the > experimental support for unicorns in zoology. Lots of luck proving either > exists. I agree .. the existence of an aether is not falsifiable. Unless perhaps some GR predictions (say)would be incompatible with an aether (but compatible with SR). I'm certainly not aware of any test that would allow one to test for its presence or not. If that is the case, then we cannot scientifically prove or refute that aether exists. Occam's razor wipes out aether as being required for physics. If it exists, it makes no difference to how we measure reality.
From: Paul Stowe on 7 Mar 2010 22:04 On Mar 7, 6:52 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > LET is as possibly valid as SR .. Neither is refuted experimentally. I > > just don't think it is the correct physical explanation. LET is not > > compatible AFAIK with GR .. so is a bit of a dead end .. and has the > > assumption of an undetectableaetherwith properties that don't make > > sense. > > The experimental support for a fixed ether in SR is comparable to the > experimental support for unicorns in zoology. Lots of luck proving either > exists. What is a 'fixed ether'? Paul Stowe
From: Paul Stowe on 7 Mar 2010 22:07
On Mar 7, 7:04 pm, Paul Stowe <theaether...(a)gmail.com> wrote: > On Mar 7, 6:52 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > wrote: > > > > LET is as possibly valid as SR .. Neither is refuted experimentally. I > > > just don't think it is the correct physical explanation. LET is not > > > compatible AFAIK with GR .. so is a bit of a dead end .. and has the > > > assumption of an undetectableaetherwith properties that don't make > > > sense. > > > The experimental support for a fixed ether in SR is comparable to the > > experimental support for unicorns in zoology. Lots of luck proving either > > exists. > > What is a 'fixed ether'? > > Paul Stowe Oh, and BTW, please derive the physical basis of the LTE within the framework of SR. Thanks, |