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From: Ste on 4 Mar 2010 05:41
On 4 Mar, 02:14, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au>
wrote:
> "Ste" <ste_ro...(a)hotmail.com> wrote in message
>
> >> > If you had,
> >> > you'd also have found out that *creationists* (who you've oddly chosen
> >> > to commandeer in your support) also make this argument, and yet Popper
> >> > later recanted this criticism. In fact I seem to remember that the
> >> > page I linked to on talk.origins also mentioned this. And yet you
> >> > claim to know all about evolution and all about the arguments of
> >> > creationists.
>
> >> Let me get this straight. You seem to think that you had some evidence
> >> which
> >> was linked to page published on anewsgroup I don't subscribe to ...
>
> > I gave you the bloody link the other day Peter. And I've given it
> > again at the top of this post.
>
> It does not address the tests of falsifiability of evolution that I gave.
> And the link you provided is not to Lakatos, its just some random person.

This is the only point worth responding to. The link was not to
Lakatos. It was a link to a page which talked about Popper's criticism
of Darwin. You complained that you didn't believe me and didn't have
access to the newsgroup, and I pointed out that the page was not on a
newsgroup, it was a web page, the link to which I've repeatedly posted.
From: Peter Webb on 4 Mar 2010 05:50

SR specifically predicts that if one twin travels away at high speed and
returns, they will have aged less than the stay at home twin.

This prediction of SR is completely independent of any subsequent
predictions of GR concerning time dilation due to acceleration, which in any
event is even more negligible.

It is a direct consequence of time dilation.

You said you believed SR.

Do you believe that as a result of the time dilation predicted by SR that if
one twin traveled away from earth at 0.9c for a year, bounced of some disant
trampoline and returned to the earth for another year, the twin on the
rocket will have aged less due to the time dilation predicted by SR?

If you do not, then you do not believe SR.

If you do, explain how the fact that one twin is older is due to
"propogation delays".

Do you even know what you believe?

*Inability to learn*




From: Ste on 4 Mar 2010 05:54
On 4 Mar, 09:39, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au>
wrote:
> "Ste" <ste_ro...(a)hotmail.com> wrote in message
>
> news:8984b4b4-92e9-466a-ad51-20e6b4e815bc(a)u9g2000yqb.googlegroups.com...
> On 3 Mar, 22:23, "Inertial" <relativ...(a)rest.com> wrote:
>
>
>
>
>
> > "Ste" <ste_ro...(a)hotmail.com> wrote in message
>
> >news:64d02f70-01e4-44a5-a5ab-41429bf37f71(a)q15g2000yqj.googlegroups.com...
>
> > > I'm sure I said something about the ludicrous assertions that some
> > > people here have made about the conceptual basis of SR. That is,
> > > assertions that verge on meaningless, like "rotation into time" as an
> > > explanation for length contraction. Or even observed time dilation (in
> > > SR) being "real" as opposed to merely a function of propagation
> > > delays. But none of this fundamentally challenges SR.
>
> > Time dilation isn't anything to do with propagation delays .. they do NOT
> > cause time dilation. It IS real in that it has been measured
> > experimentally.
>
> > Your denial of reality is another trademark of a crackpot.
>
> I'm not denying it. I'm saying experiments that involve acceleration
> are the realm of GR (as I understand it), and that acceleration is the
> cause of "real" time dilation. We're talking about SR, and therefore
> we cannot be talking about any experiment that involves acceleration.
>
> ________________________________
> It is true that you cannot devise an experiment whereby two clocks are
> together and then separated without at least one of them experiencing
> acceleration at some point; that unfortunately is a mathematical fact, not a
> physical one.

No, it is a physical fact.



> However, you can make the contribution of acceleration "vanishingly small",
> by designing thought experiments where the accelerations are very low and
> slow. Sending a rocket to another star is one such example.

Not really, because if the total acceleration is small, then so is the
speed.



> You now appear to be claiming that you *don't* believe the twins will be
> different ages due to simple time dilation in SR, which means you *don't*
> agree that SR is correct.
>
> So, yet again, like the uber-crank you are, you have completely changed your
> story.
>
> Yesterday you believed in the predictions of SR. Now you say you don't.
>
> Its called *inability to learn*.

<yawn>
From: Jerry on 4 Mar 2010 07:15
On Mar 4, 2:12 am, Ste <ste_ro...(a)hotmail.com> wrote:

> I pay attention. It's just that I've been asking for weeks for an
> explanation for this assertion that time slows down in SR above and
> beyond the "apparent" effect due to propagation delays, and all I keep
> getting in return is a bald assertion that this is the case, even
> though I've made it quite clear that I do not find this bald assertion
> believable.

This has been brought up to you before, but you have -not- paid
attention.

Consider muons traveling at high speed in a circular path, as
for instance in the g-2 experiment. The measured lifespan of
muons in this scenario is much greater than that of stationary
muons. This effect is consistent with relativistic predictions.

Yet the "average" propagation delay that exists between an
observer standing beside the ring and the circulating muons must
be zero.

Jerry
From: Inertial on 4 Mar 2010 07:16

"Ste" <ste_rose0(a)hotmail.com> wrote in message
news:3ba45de3-bdb9-4693-b15a-d58d0f4d929f(a)t23g2000yqt.googlegroups.com...
> On 3 Mar, 22:59, PD <thedraperfam...(a)gmail.com> wrote:
>> On Mar 3, 11:52 am, Ste <ste_ro...(a)hotmail.com> wrote:
>>
>> > On 3 Mar, 12:30, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au>
>> > wrote:
>>
>> > > "Ste" <ste_ro...(a)hotmail.com> wrote in message
>>
>> > > >> You say you are here to learn about SR.
>>
>> > > > I am here to learn more about the *conceptual basis* of SR.
>>
>> > > Minkowksi space time?
>>
>> > No.
>>
>> How about just spacetime, then, for which there is both a conceptual
>> description and a mathematical description?
>
> No. I would go as far as saying I don't want another word said about
> spacetime as a means of answering any of my questions.

Tough .. it is an intergral part of SR. You don't get to decide what is SR
and what isn't

> If an
> explanation falls back on appealing to the truth of even a single
> equation,

Who said anything about equations?

> then the explanation is defective as an answer to my
> questions.

No .. it is YOU who are defective, by refusing to listen to valid
explanations because you refuse to learn enough math to understand them.
You're truly an arrogant ignorant idiot. The worst kind there is.

>> > > >> Do you believe SR is true?
>>
>> > > > I accept it's mathematical form has some obvious truth, yes.
>>
>> > > Do you believe that it correctly predicts the results of every
>> > > experiment
>> > > that it claims to? That clocks run slower,
>>
>> > No. In SR, clocks *appear* to run slower as you are increasing your
>> > distance from the clock. The effect is entirely apparent in SR.
>>
>> That's not the extent of what SR claims. Muons in a circulating ring
>> exhibit time dilation, though they are not receding from the clock at
>> all, for example.
>
> What they exhibit is a longer half-life.

Yes

> But I'm not sure that a
> single variable, time, has been isolated here. Firstly, there is
> constant acceleration if the particle is in a ring (and it seems
> unarguable that acceleration causes some kind of real change in
> behaviour at an atomic level).

Careful there might be some math involved there.

> Secondly, were an observer travelling along with the muon, he may also
> report an increased half-life, as against if he and the muon were
> stationary relative to the ring - possibly because the cause of decay,
> which is assumed to be random, is actually influenced by the fact that
> the environment (as perceived by the muon) is spinning at relativistic
> speeds.
>
> There is certainly a need to account for this behaviour, but I am not
> sure it is accounted for by time dilation as opposed to the physical
> reality that the muon really is decaying slower.

There is other experimental evidence.

>> > > and 80 foot ladders can fit through 40 feet barns,
>>
>> > It remains slightly unclear, but I'm inclined to say no, although it
>> > can certainly be made to appear to happen in certain circumstances.
>>
>> I would be cautious about inclinations. It is pretty easy to make the
>> distinction between "appears to" and "does". For example, if I hold
>> the doors of the barn open to admit the pole, and at a carefully
>> chosen moment, briefly close both barn doors simultaneously and then
>> open them again, in such a way that I can verify that the both ends of
>> the pole had entered the barn before I closed both doors, then I can
>> be pretty sure that the pole was wholly in the barn. I can also then
>> check whether there were any strike marks on the barn doors where the
>> pole would have struck them. If there are none, then this pretty well
>> unambiguously tells you the pole WAS inside the barn, not just
>> appeared to be inside the barn. If you think those events (no marks on
>> the barn doors, both doors closed simultaneously after entry of the
>> pole) can be observed while still maintaining the pole does not fit in
>> the barn, you'll have to explain to me how this is.
>
> This door-marking test is nice in principle, and I agree that the
> results would be conclusive. However I fear it is not a test that is
> implementable in practice with real materials.

It is impractical. But a 'real' contraction (not just some illusion) is
what SR predicts.

I'd explain how, but you don't want to know


>> > > and that the speed of light is measured the same in
>> > > every intertial frame of reference and this speed is independent of
>> > > the
>> > > speed of the emitter, receiver, and underlying medium of
>> > > transmission?
>>
>> > Yes. I think I've been able to reconcile this partially, but only
>> > vaguely and within a definitely non-standard conceptual framework, and
>> > it is forced to completely dispense with any corpuscular form of
>> > matter, and instead relies wholly on fields. Unfortunately it's
>> > probably the sort of thing that physicists spend their lives thinking
>> > about and never quite put their finger on.
>>
>> Aha. I hope you did not sprain your wrist while hand-waving.
>
> Lol.
>
>
>
>> > > If you believe all of those things, then you are saying more than "SR
>> > > has
>> > > some obvious truths in its mathematical form" you are saying it is an
>> > > accurate portrayal of reality - ie, what happens when you conduct
>> > > those
>> > > experiments, what physically and actually happens, is exactly as
>> > > predicted
>> > > by Relativity.
>>
>> > I think we all agree that SR portrays reality, but none of us seem to
>> > be able to agree on what kind of reality it portrays.
>>
>> Do you believe there is more than one kind of reality? Namely, do you
>> believe there is a reality that matches your expectations for the
>> orderliness of that reality, and another reality that does not
>> necessarily meet those expectations?
>
> I'm a materialist (i.e. realist). You can't be a materialist and
> believe in more than one kind of reality.

You are deliberately ignorant.

>> > > If, on the other hand, you do not believe in the twin "paradox"
>> > > actually
>> > > happening, you don't believe in SR.
>>
>> > We resolved the twins paradox months ago. The astronaut twin undergoes
>> > asymmetrical acceleration, and that is why he returns younger.
>>
>> Yes, but that is still very much the prediction of SR.
>
> I didn't realise SR could cope with acceleration. I thought that was
> what GR was required for?

There is a lot you do not know and do not realize. And it will stay that
way.

>> > > If you do believe the predictions of SR
>> > > that one twin is older, then you believe that time dilation is more
>> > > than
>> > > some mathematical fiction, its what actually happens in the real
>> > > world.
>>
>> > On the contrary. The involvement of acceleration, which is the domain
>> > of GR, makes me wonder why this is held to be a paradox in SR at all.
>>
>> This is incorrect. SR can handle acceleration just fine. What matters
>> here, and what marks the difference between the twins, is the
>> straightness of the path (a special term called "worldline" in
>> physics) in spacetime. Straighter paths consume longer "proper
>> time" (another specialized term in physics).
>
> Yes, and off we go into la-la land again.
>
> (I know exactly what you're describing, but it is the most obtuse way
> of describing the essential physical reality.)

You wouldn't know .. you are deliberately ignorant.

>> > And yes, the acceleration causes real effects for the astronaut twin.
>>
>> Yes indeed, and it is remarkable that the effects are precisely in the
>> quantity that is predicted by SR.
>
> I need some clarification Paul. My understanding is that SR does not
> deal with acceleration

You've been corrected several times already .. how many times do you need to
be told before it sinks into your thick skull

>- one must "reanchor" the frame of reference
> each time velocity changes. Now is that correct or not?
>
>
>
>
>> > > You seem to agree they are "mathematical truths". Do you also agree
>> > > those
>> > > equations correctly predict the outcomes of real world experiments,
>> > > which
>> > > means they are far more than simply "mathematical truths"?
>>
>> > The question is of interpreting the mathematical predictions. As I say
>> > above, there is a difference between what is real and what is merely
>> > apparent.
>>
>> See above regarding the pole and the barn. In terms of the
>> observations given, you'll have to explain to me how the pole would
>> have really NOT fit into the barn (but only apparently) and been
>> consistent with the observations noted.
>
> Ok. We have an observer standing by a door of the barn. We call this
> the near door. The other door is the distant door. Now, we close the
> distant door, and then reopen it. Then we send the ladder in (at
> relativistic speeds). The observer watches the ladder go in. Then we
> close the near door behind the ladder. The propagation delays from the
> distant door mean that, according to the observer standing by the near
> door, the doors are closing simultaneously, but in fact the distant
> door had closed and reopened before the ladder had even entered the
> barn. Hence the ladder fits apparently, but not really.

Nope. That's not what happens at all. Again . you are deliberately
ignorant. Or a liar.


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