Known physics defeated by simple puzzle?
in [Relativity]
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From: Inertial on 4 Apr 2010 20:38 "Ste" <ste_rose0(a)hotmail.com> wrote in message news:64863a88-92a3-4fdc-bd9b-a17d0ec55602(a)30g2000yqi.googlegroups.com... > On 4 Apr, 23:41, "Inertial" <relativ...(a)rest.com> wrote: >> "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >> > or whether the relativistic speeds cause a sort of >> >> > lensing effect (i.e. like putting a prism in front of one's eyes, >> >> > the >> >> > "contraction" affects only the person with the prism in front of >> >> > their >> >> > eyes) that makes everything *appear* contracted, but there is >> >> > actually >> >> > no measurable change at all in the rest of the universe. >> >> >> No, its not an optical illusion, for the 8 billionth time. >> >> >> The travelling twin really is younger. >> >> > We agreed last time that if the two twins both go into space, in >> > opposite directions, and then return, then they remain the same age as >> > each other (technically, they both end up younger by the same amount, >> > than a person who stayed on Earth). >> >> Irrelevant to the 'twins paradox'. > > It isn't, Glad you agree it isn't relevant > because what I'm showing is that the time dilation in SR is > due to acceleration, More precisely, due to change in rest inertial frame > which is not relative. Noone is claiming that it is. > Incidentally, this book (which was a link from Wikipedia) confirms my > statement that GR is how the paradox was apparently resolved (at least > by Einstein and a few others): > http://books.google.com/books?id=vuTXBPvswOwC&pg=PA165#v=onepage&q=&f=false You CAN use GR .. which is a superset of SR. But SR 'solves' it as well >> > This is due to acceleration, >> >> Well. to change in rest inertial frame > > Never mind, for now. There can be a difference. So you probably should mind. >> > but >> > as I understand it, you need GR to account for acceleration (in other >> > words, it's outside the scope of this discussion). >> >> Wrong .. you've had that told to you many times. SR handles acceleration >> just fine > > As I say, the information I have suggests that GR is necessary to > account for the (absolute) acceleration, That is wrong > whereas SR treats > acceleration merely as a change of relative velocity It is a change in velocity > (which may or may > not involve "real" acceleration - the kind that would be registered on > an accelerometer). If it is acceleration, it would register on an accelerometer You are making distinctions where there are none >> >> The ladder really does fit inside the barn. >> >> > But then it must fit inside the barn from *all* frames, >> >> Why? > > Because "fitting" and "not fitting" are two mutually exclusive states. You haven't answered the question >> It doesn't have the same speed in all frames. It doesn't have the >> same momentum in all frames. It doesn't have the same kinetic energy in >> all >> frames. Why must it have the same length? > > Because the notion of "speed", "energy" and "momentum" are all > inherently relative concepts. As are length and duration > If I hit someone over the head with a > hammer, then the force applied to the skull depends on the relative > speed of the hammer and the skull. But all observers agree about the > force of the impact between the hammer and the skull - in other words, > I do not crack his skull wide open according to some observers, and > merely daze him according to others. And that is the same in SR .. either something happens or it doesn't > The same is true of this ladder problem. If the ladder contracts, then > it will fit in the barn, and if it doesn't contract then it won't fit > - but it cannot contract at the same time as not contracting, or fit > at the same time as not fitting. Wrong > However, it can *appear* to do so by careful timing of the doors and > careful placement of the observer, and so naturally I'm saying to > myself "this must be what you mean". No .. it really fits. You really need to understand the scenario before drawing conclusions from it >> > including the >> > rest frame of the ladder. And I know that is not what SR predicts. >> >> But you are insisting that only things that are frame independent are >> real >> (which rules out a large amount of what we measure and work with in >> physics). > > No, I'm insisting that observations/changes can have a "real" basis, > or an "apparent" basis, at least for the purposes of this argument . So velocity, momentum etc do not have a real basis, according to your logic > And indeed, a lot of the things you may be working with and measuring > in physics are "apparent" and not "real". And I will state the > definition of "apparent": "appearing as such but not necessarily so". So velocity, momentum etc do not have a real basis, according to your logic > So when we talk of "clocks slowing down", we need to be clear about > whether we're talking about the clock *appearing* to slow down (but > continuing to tick at the normal rate), or whether it is *really* > slowed down. (More on this below.) Depends on what you mean by 'real'. Your usage is problematic, as you are excluding a wealth of things that are considered 'real' by reasonable people and physics >> So if you stand on the the highway and a car travelling at 100km/h runs >> into >> you, you don't need to worry, because it isn't really travelling fast >> (velocity isn't real by your standard), and doesn't really have a large >> amount of momentum and kinetic energy (momentum and kinetic energy isn't >> real by your standard) that it imparts into you and your death isn't >> real. > > But I will be apparently dead. ;) So you die from apparent causes and not real ones. > Seriously though, I didn't say velocity was "not real", Yes .. you did .. when you said something is only real if it is the same for all observers > but it is a > relative concept (that is, it is an interaction of two objects, not a > property of one object; and it is still invariant across all frames, > in that the car hits the person with the same force, and the same > effect, no matter where you look at it from). Just like a pole fitting in a barn .. that is an interaction of two objects > Also, I'd be interested to return to a discussion I'm sure you would, as your current postition on 'real' has been shown as rather silly. > about my "speaking > clock" - I had previously said that it ticked loudly, but let's make > it even more easy to imagine by saying that it consists of just black > box with an audio speaker, and it "speaks" the time out loud every > second. Do you not accept that the faster you move away from the > speaking clock, the slower the clock appears to go? That's an audio illusion (or optical if you are reading the time) due to delays in signal. That is NOT what happens in SR when we say clocks are measured as running slow. You really need to understand what SR actually says before making conclusions about it.
From: Sue... on 4 Apr 2010 21:31 On Apr 4, 8:26 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Sue..." <suzysewns...(a)yahoo.com.au> wrote in message > > news:8185f44e-a0bb-4c3d-906e-117c1616aaf6(a)q15g2000yqj.googlegroups.com... > On Apr 4, 10:28 am, "Peter Webb" > > > > or whether the relativistic speeds cause a sort of > > > lensing effect (i.e. like putting a prism in front of one's eyes, the > > > "contraction" affects only the person with the prism in front of their > > > eyes) that makes everything *appear* contracted, but there is actually > > > no measurable change at all in the rest of the universe. > > ================== > > > > > No, its not an optical illusion, for the 8 billionth time. > > > The travelling twin really is younger. > > > The ladder really does fit inside the barn. > > In spite of recent cautions not to appeal to authority, > I think you will find some important contributors > to Einstein's relativity are diametrically opposed > to you view. > > ________________________________________ > OK, name one physicist who believes that the travelling twin would not > return younger. Nearly all and you just snipped the reason why. > No, its not an optical illusion, for the 8 billionth time. > The travelling twin really is younger. > The ladder really does fit inside the barn. In spite of recent cautions not to appeal to authority, I think you will find some important contributors to Einstein's relativity are diametrically opposed to you view. << Application of Noether's theorem allows physicists to gain powerful insights into any general theory in physics, by just analyzing the various transformations that would make the form of the laws involved invariant. For example: * the invariance of physical systems with respect to spatial translation (in other words, that the laws of physics do not vary with locations in space) gives the law of conservation of linear momentum; * invariance with respect to rotation gives the law of conservation of angular momentum; * invariance with respect to time translation gives the well-known law of conservation of energy >> http://en.wikipedia.org/wiki/Noether%27s_theorem#Applications Nina Byers (1998) "E. Noether's Discovery of the Deep Connection Between Symmetries and Conservation Laws." http://arxiv.org/abs/physics/9807044 Sue...
From: Inertial on 4 Apr 2010 21:55 "Sue..." <suzysewnshow(a)yahoo.com.au> wrote in message news:b0d31ce6-409d-4e59-9940-e3b780c70a95(a)k19g2000yqn.googlegroups.com... > On Apr 4, 8:26 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > wrote: >> "Sue..." <suzysewns...(a)yahoo.com.au> wrote in message >> >> news:8185f44e-a0bb-4c3d-906e-117c1616aaf6(a)q15g2000yqj.googlegroups.com... >> On Apr 4, 10:28 am, "Peter Webb" >> >> > > or whether the relativistic speeds cause a sort of >> > > lensing effect (i.e. like putting a prism in front of one's eyes, the >> > > "contraction" affects only the person with the prism in front of >> > > their >> > > eyes) that makes everything *appear* contracted, but there is >> > > actually >> > > no measurable change at all in the rest of the universe. >> >> ================== >> >> >> >> > No, its not an optical illusion, for the 8 billionth time. >> >> > The travelling twin really is younger. >> >> > The ladder really does fit inside the barn. >> >> In spite of recent cautions not to appeal to authority, >> I think you will find some important contributors >> to Einstein's relativity are diametrically opposed >> to you view. >> >> ________________________________________ >> OK, name one physicist who believes that the travelling twin would not >> return younger. > > Nearly all and you just snipped the reason why. You seem to confuse 'nearly all' with 'none' >> No, its not an optical illusion, for the 8 billionth time. > >> The travelling twin really is younger. > >> The ladder really does fit inside the barn. > > In spite of recent cautions not to appeal to authority, > I think you will find some important contributors > to Einstein's relativity are diametrically opposed > to you view. > > << Application of Noether's theorem allows physicists to > gain powerful insights into any general theory in physics, > by just analyzing the various transformations that would > make the form of the laws involved invariant. For example: > > * the invariance of physical systems with respect > to spatial translation (in other words, that the laws > of physics do not vary with locations in space) gives > the law of conservation of linear momentum; > * invariance with respect to rotation gives the law > of conservation of angular momentum; > * invariance with respect to time translation gives > the well-known law of conservation of energy >> > http://en.wikipedia.org/wiki/Noether%27s_theorem#Applications > > Nina Byers (1998) > "E. Noether's Discovery of the Deep > Connection Between Symmetries and Conservation Laws." > http://arxiv.org/abs/physics/9807044 Which does not have anything to do with what you claim.
From: Sue... on 4 Apr 2010 22:54 On Apr 4, 8:26 pm, "Peter Webb" ============= > OK, name one physicist who believes that the travelling twin would not > return younger. Most physicist realise that free time is free energy and "there ain't no free lunch" << * invariance with respect to time translation gives the well-known law of conservation of energy >> http://en.wikipedia.org/wiki/Noether%27s_theorem#Applications Here is something to ponder. It is widely held that a torsion pendulum or Mossbauer oscillator will slow with proximity to planet and would slow more near Jupiter compared to Earth. http://en.wikipedia.org/wiki/Pound%E2%80%93Rebka_experiment Do you really think the extra ~200 pounds you would have to carry on Jupiter would extend your life? The few physicists that give any credence at all to the slowly aging twin, will fold up their tent when you point out that the experiments used to support the myth are with charged particles subject to the Lorentz force and therefore not moving inertially. Besides... It doesnt take a lot of brains to figure out that some kind of ether or absolute frame is necessary to make one twin accurately experience motion dependent forces different from the other twin. There are still some proponents of that among us and some even wear tin foil hats so aliens won't send them messages to change their minds. :-)) Maybe you should read about them so you don't emullate them. So far you have me fooled. http://en.wikipedia.org/wiki/Lorentz_ether_theory#Later_activity_and_Current_Status Sue...
From: Peter Webb on 5 Apr 2010 01:19
"Sue..." <suzysewnshow(a)yahoo.com.au> wrote in message news:b0d31ce6-409d-4e59-9940-e3b780c70a95(a)k19g2000yqn.googlegroups.com... On Apr 4, 8:26 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Sue..." <suzysewns...(a)yahoo.com.au> wrote in message > > news:8185f44e-a0bb-4c3d-906e-117c1616aaf6(a)q15g2000yqj.googlegroups.com... > On Apr 4, 10:28 am, "Peter Webb" > > > > or whether the relativistic speeds cause a sort of > > > lensing effect (i.e. like putting a prism in front of one's eyes, the > > > "contraction" affects only the person with the prism in front of their > > > eyes) that makes everything *appear* contracted, but there is actually > > > no measurable change at all in the rest of the universe. > > ================== > > > > > No, its not an optical illusion, for the 8 billionth time. > > > The travelling twin really is younger. > > > The ladder really does fit inside the barn. > > In spite of recent cautions not to appeal to authority, > I think you will find some important contributors > to Einstein's relativity are diametrically opposed > to you view. > > ________________________________________ > OK, name one physicist who believes that the travelling twin would not > return younger. Nearly all and you just snipped the reason why. _____________________________________ Name one. |