Re: SR consistency is crap.

From: Eric Baird (eric_baird_at_compuserve.com)
Date: 11/29/04 

Date: Mon, 29 Nov 2004 01:52:05 +0000 (UTC)

On 24 Nov 2004 11:40:22 -0800, troubled6man@yahoo.com (J.E.) wrote, in
message <39d6e584.0411241140.e731620@posting.google.com>:

>eleatis@yahoo.gr (Mike) wrote in message news:<9c1b39be.0411240316.7f0b7da7@posting.google.com>...
>> troubled6man@yahoo.com (J.E.) wrote in message news:<39d6e584.0411231204.5010b537@posting.google.com>...
>>
>> [snip]
>> >
>> > I disagree. SR is about a proposed symmetry of nature.
>>
>> Explain the twin paradox then. By the way, introducing accelerations
>> or boosts is a departure from SR and a move into the Dynamics domain.
>
>I'd be happy to explain the twin paradox. Start with the "financial
>twin paradox" that I just explained to eleaticus. And I disagree
>about accelerations and boosts being outside SR, altough I understand
>why people ignore it. SR is a theory about how the symmetries of
>spacetime are similar to the symmetries of Minkowksi geometry. That's
>why the "financial twin paradox" using an indefinite quadratic form to
>determine the rate at which money is sucked out our your pocket and
>sent to someone else.
>
>> > > You got a problem right from the start. SR came to
>> > > challenge the Copernican view of the world (see Hans Reichenbach, The
>> > > Philosophy of Space and Time) the cornerstone of Newton's dynamics.
>> > > Ptolemaic and Copernican systems are kinematically equivalent
>> > > according to Relativity. Yet, while admitting SR, the educational
>> > > status quo refuses to drop Newtonian dynamics, claiming there is ample
>> > > emprirical evidence to support it. Actually, sicne Newton's laws are
>> > > mere tautologies, in non-relativistic limits they will always conform
>> > > to experiment.
>> >
>> > Newtonian dynamics are not dropped. They are derived locally, you
>> > already conceded that below that they are local tautologies. A
>> > dynamic isn't much without a law about elementary forces.
>> >
>> > > I took Physics 101 and Modern Phycsi 101 together during the same
>> > > semester as soon as I started undergraduate. The mentor protested and
>> > > argued I should take Modern Physics (Relativity) after I take
>> > > Classical Mechanics, because that was a prerequisite. I protested, I
>> > > argued it must be my choice not theirs. I won. I got a A- in Classical
>> > > and an A+ in Modern.
>> >
>> > Good for you. I didn't even realize I liked physics until Modern
>> > Physics (which for us covered QM, solid state, Stat mech, etc. too) I
>> > just took it as "an easy class" since I was good at math.
>>
>> Yesy, interesting to see that while it is an easy subject for some
>> people it is beyond comprehension for others.
>
>I think it's bad teaching. If I had a "good background" to easily
>understand a fixed way of teaching the subject, that doesn't make "the
>subject" inherently hard for others or easy for me, in means by
>background and the teaching lined up well.

Funnily enough, I found that it was actually very easy to explain GR
principles to complete physics newbies, with a suitable choice of
words.

You just say things like, "increasing the strength of gravity in a
region seems to make makes space seem more dense and time more
rarefied, so that clocks there tick more slowly ... so if we want to
create a map of the light-distances in a slice through the region, so
that the distances in the map correspond to the distances in the
region, we have to extrude the map in order ot be able to cram in the
extra space (produce diagram of gravity-well, with a flourish).

People seem to "get" that. You might get an occasional "Gravity makes
local time appear to go by slower? Really?" "Yup!" "Oh, Okay then"

But try to explain SR time dilation to the same person, and they'll
usually get upset and insist that the thing is rubbish.

So untrained people seem to be intuitively happier with supposedly
"advanced" ideas like spacetime curvature than "simple" ones like SR's
Minkowski metric (I found). They seem to find most of the GR-ey
principles easier to visualise and accept, "stars bend light" or
"gravity slows time" or "rotating stars pull stuff around with them"
seem to be easier concepts to take onboard than "moving astronauts age
slower than each other".

Maybe schools should teach the principles of general relativity first,
and leave SR to the more "advanced" students. ;)

  
>> > > I think this is the way to go. Teach students everything together as
>> > > competing theories and not relativity as an advance extension to
>> > > Newtonian Dynamics.
>> >
>> > I'd rather teach QM from the start, and get special relativity as a
>> > limiting case of that, and then Newtonian dynamics as a special case
>> > of that.
>>
>> Well, you are talking 1000 years from now when we will understand
>> better how quantum uncertainty gives rise to macrocosmic certainty.
>> For now, such approach can result only in confusion.
>
>You seem to have strong opinions about things you obviously don't
>know. Bohm did a good job of explaining maro-certaintanty as a
>statistical effect from a large number of quantum particles. And that
>was decades ago. Teaching is always behind the cutting edge.

I was taught at school that Newton's prism experiment proved that
light was composed of seven colours, and we were made to memorise the
seven colours and conduct the experiment ourselves and "see" the seven
colours ourselves.

Then we were given coloured filters to play with and were taught that
white light was actually composed of three distinct colours, and we
were shown how to conduct expeirments to prove /that/.

No wonder the poor kids were a bit bewildered.

I survived those classes by being arrogant enough to assume that if
something sounded wrong it was probably bull***.
Hopefully anyone going through that syllabus with a real talent for
physcs woudl have realised that thge problem was not with them but
with the teaching, but I do sometimes wonder how many "adepts" leave
physcs because they think,wrongly, that their misgivings about certain
subjects are becuase they arenlt good at the subject.

If the people taking up the subject are predominantly people who are
more prepared to suspend disbelief than the norm, then that might not
be good for the subject. I suppose the people who already have a
grounding in physcs before they take the class (eg family background),
or those who are pig-headed enough to believe that they are right and
the system is wrong, may still get through.

I do notice that a strangely high percentage of physics people seem to
have physicists or teachers as parents or as elder siblings etc,
Perhaps a support network makes it easier for one to survive
introductory physics classes without having one's brain scrambled.

 
>> > > But remember, you still have a problem. SR+GR are
>> > > axiomatic systems. No different from Euclidean geometry in that
>> > > respect. You gain understanding of the theories early on but also you
>> > > raise the doubt in their foundations.
>> >
>> > Huh? You want to avoid doubt? Science has doubt, predictions are
>> > made, the predictions can be compared to data, they might pass or
>> > fail.
>> >
>> > > Eventually, someone will lose.
>> >
>> > Only theories can lose, not people, please explain more what you mean.
>>
>> I meant that popularization of SR, GR will turn out more questioning
>> and eventually abandoment. This is the fate of every theory that
>> becomes pupolarized.
>
>I seriously doubt that. I think that when the correct SR theory is
>finally popularized the "incorrect alleged SR theories" will FINALLY
>be adandoned, and not a moment too soon, yeak!

I think that perhaps part of why SR is such a bad "subject" is that
there are probably a lot of pro-SR people strenuously insisting that
what they were taught is right, even when it isn't.

I think the Penrose/Terrell case illustrates this nicely, we had a
situation where professional physcists had supposedly been pushing a
"wrong" result for decades, even though it disagreed with the math,
because they had been /taught/ that moving objects are seen to be
contracted under SR.
Social conditionaing overrode mathematics and geometry.

Penrose was a mathematician who snuck his result out as a
non-peer-revirewed letter in an obscure local journal, Terrell was an
undergraduate who struggled for years to get his paper through peer
review.
So the matter was eventually tackled by a newbie and a mathematican,
not by mature "physics" people.

For some reason, these things always seem to end up being corrected by
outsiders, the highly-trained mainstream don't seem to be willing or
able to do it themselves.

 
 
>> > > Those that are afraid of ending up with a loser keep SR+GR as advance
>> > > subjects.
>> >
>> > I'd love to have GR and SR as grade-school subjects, does that mean
>> > I'm not afraid of losing? I don't know what you mean by "afraid of
>> > losing" or "lose", I do hope my predictions match the data, that's
>> > because if it's easy to be wrong, so why bother learning a theory if
>> > it makes wrong predictions?
>> >
>> > > Remember what happened to Euclidean geometry?
>> >
>> > What happened? It's still around!
>> >
>> > > As soos as
>> > > they started teaching it, thousands attempted to disprove the Playfair
>> > > axiom (parallel lines never meet). The result was a
>> > > relative-consistency with spherical and hypoerbolic geometries.
>> >
>> > Elemetary euclidean geometry was proved consistent, you can drop
>> > "relative-consistency" and just say "consistent" if what you mean is
>> > that elementary hyperbolic geometry is as consistent as elementary
>> > Euclidean geometry. And if you mean something other than elementary,
>> > then that useally means bringing in sets and once you've done that
>> > then all become equiconsistent with set theory.
>>
>> I agree. But I hope you recall that the consistency of Euclidean
>> geometry was under question for some time.
>
>Well, the same grounding to elementary euclidean geometry applies to
>elementary hyperbolic geometry, and I can do SR predictions with
>ELEMENTARY hyperbolic geometry. If you want not instantaneous
>accelerations, then I need FULL hyperbolic geometry, which is as
>consistent as FULL euclidean geometry.

Mmmm, but the GR experience has hopefully taught everyone that
mathematical consistency is not necessarily enough -- in physics, a
structure also has to be "appropriate".

If basic Euclidean geometry is consistent, it doesn't neccessarily
mean that it is appropriate or sufficient for describing lightbeam
geometry in the presence of gravitational fields or accelerating
masses (until you start adding dimensions), or even relativiely moving
masses.

So a theory or model can be completely consistent in its own
(artificial) context, but physcally wrong when it comes to attempts to
use it to model the behaviour of the real world.
Mathematical theorems can appear to be rock-solid, but still be
hopelessly wrong (or misunderstood) in the context of attempts to
construct physical theory.
Nuances of language can be incredibly important.

 
>> > > The
>> > > same will happen to SR+GR as soon as they became a target of the
>> > > masses.
>> >
>> > What will happen to SR+GR (which is GR, unless you meant "the same
>> > will happen to SR and the same will happen to GR as soon as each
>> > becomes a target of the masses)? And what masses are currently kept
>> > away from it?
>> >
>>
>> The majority of people fails math and you should know that. The
>> majority works using a common sense basis. Anything as advanced as GR
>
>People fail at math because of math is taught badly. Did you know
>that you can multiply vectors? Life is easier with that, and hard
>without it.

I was a math whizz as a pre-adolescent.
I nearly failed my "eleven plus" test because it contained a set of
letter-number substitution problems, and I couldn't crack the rolling
encryption model they were using. Without having any math background I
spent that test filling sheets of paper running through the different
conceivable encryption systems that they might have been using
(fractional number bases, etc) until I finally came up with the idea
of using prime number sequences as a key, and I spent a quarter of the
test period working on the problem of how to arbitrarily quantise a
range of coordinate-free number surfaces representing different forms
of number system before realising that it was going to take me at
least another half hour and there were only ten minutes left.
So I cheated with the first example (CAT=XXX, DOG=XXX, COG=???), by
just doing a dumb substitution, and then realised that every other
example worked the same way.
I distinctly remember feeling panicky and inadequate, looking around
at a hall filled with other elevenyearolds scratching away, and
thinking I was the only one there who didn't know how to crack the
output of a a prime number encoding system.

Anyhow, I only mention this because after starting secondary school
and spending years laboriously practicing cross-multiplication day
after day (and being accused of cheating when I didn't include
"working out", which was an alien concept to me at the time), the math
part of my brain shrivelled up until I eventually had such a strong
mental block to do with anything mathy that I had to drop out of
school because I could no longer even add and subtract reliably.
My brain was just stalling on me.
I had used to go through science subjects just writing down the first
number that came into my head and getting the answers right. Then the
magic stopped working.

The power of aversion therapy I guess. :(

(I still can't do math any more, but I have some dim memories of what
it was lke when I could, and I remember being distinctly unimpressed
with what was inthe textbooks).

> will create a reaction and eventually will be dropped, creating more
>> problems than the intended solution. Another solution recently
>> proposed is to make physics a subject for selected few.
>
>I will concede that fixing math eduation is paramount to fixing
>physics education, there isn't a strong reason not to do both by
>fixing the education of geometry to be incorporated "the cutting edge"
>from the 19th century, which frankly we have yet to do and that's just
>sad sad sad.
>
>> > > The current approach is to keep the theory for the few and
>> > > feed the supposed prediction to the masses via the media. Silly but
>> > > works due to hype.
>> > >
>> > > Mike
>> >
>> > I actively try to teach physics at as early a stage as possible, and
>> > books on relatively are freely sold in stores, there is no conspiracy
>> > going on. Anyone can learn. Heck, I'm on Usenet because I want to
>> > help people learn SR, among other reasons, this is a public forum
>> > where anyone can read it.
>>
>> You are wasting your time. If 95% of your student can remember all
>> three Newton's laws 2 years after graduation from any level exept grad
>> school then you have accomplished your task. You probably aiming for a
>> small % while frustrating the rest of the class and ending up with the
>> opposite that what you aim, i.e. making people dislike physics.
>
>Physics education should start out with modeling in general, and
>comparing models to data, with computers you can bury most of the math
>until a "later epistological phase" that COULD be reserved for the few
>that care, where the class discusses the foundations of the models
>used earlier. If someone isn't going to remember the basics of how to
>make or test a model, then you shouldn't BOTHER teaching science at
>all, just drill "job skills" instead.

IMO most people publishing material on SR testing don't seem to
display much ability when it comes to being able to correctly compare
models. When you see experiment after experiment looking for
transverse redshifts, finding them, and then declaring that this
result is a significant proof of SR
: "... because classical theory does not predict transverse redshifts"
, one is driven to despair.

In the experiments involved, almost every old theory in the books
would have predicted a redshift, they just wouldn't normally have
/called/ a transverse shift
(I think Oliver Lodge referred to the aether theories' "transverse"
effects as something like "false Doppler")

So ... those experimenters needed to be tapped on the shoulder and
quietly told that either the supposedly "null" transverse predictions
for other theories didn't relate to the sorts of experiments that they
were actually carrying out, or, if we used the word "transverse" to
mean "transverse as measured in the lab frame", the only way that the
statement would be correct would be if "classical theory" was defined
as being a very limited range of theories that arguably did not
include the major C19th theories, or even Newtonian mechanics.

Which would make these experiments slightly limited in what they could
tell us about how SR compared to other theories.

People who think linguistically are possibly more prone to making
mistakes when working across different theories with different
understood meaning to words, an equation is not "physics" without that
additional context. The critical legalistic "small print" is usually
not actually written down, it's instead often assumed that the physics
experts already know enough to interpret the "understood" meanings and
usages appropriately without screwing the thing up, and sometimes they
get it wrong.

Consider this logic trap:
-
Theory Proponent:
: "We know that the standard of living is far higher in the US than
: in France, because it is known, as a fact, that car ownership is
: high in the US, but that nobody in France owns or drives a car."

Sceptic:
: "But I have seen photographs of French roads filled with cars!"

Theory Proponent:
: "But those are not really cars! In France, they are more correctly
: referred to as "voitures", or "autos". So I stand by my statement,
: car ownership in France is zero, or at least negligible, and the
: original statement holds."

, and compare that misunderstanding with:

SR Proponent:
: "We know that SR is the right theory, because SR predicts
: transverse redshifts, no other theory predicts transverse
: redshifts, and transverse redshifts have been found
: experimentally."

Sceptic:
: "But almost every older theory would have predicted some sort
: of redshift effect in those SR experiments!"

SR Proponent:
: "Ah, but those would not have been properly referred to as
: /transverse/ redshifts, because according to test theory, in
: order to measure a transverse frequency under those other
: theories, one should point the detector in a different direction.
: So the original statement stands: We conducted our experiment
: according to SR protocols, we found a transverse redshift, and
: since no earlier theory predicts transverse redshifts, our result
: shows that SR is right and earlier theory was wrong."

It's like standing up at a food industry conference and stating that
"The research proves that Italy is the only place in the world where
they make Bolognese sauce for pasta",
and then when someone produces a can of the stuff made by Heinz in the
US, saying, well that's not really bolognese sauce, because in order
to earn that name, it has to be made in Bologna, Italy.

It makes the original statement a bit pointless.

With SR testing this sort of illegal switching of implied definitions
in mid-argument seems to be quite common.

---------

BTW, This is one of the reasons why I'm still an SR sceptic
(even though I count myself as a harcore relativist): apart from the
fact that many or most of the experimental SR proofs seem to have been
badly compromised, and that there still seems to me to be at least one
major theoretical loophole that hasn't yet been dealt with (and which
IMO should have been tackled decades ago), it's the sheer badness of
most of the analysis.

I don't honestly believe that physics people are usually this bad,
without good reason.

If SR was wrong, and the community was heroically struggling along
with a reference theory that didn't work properly, then perhaps those
analyses might be the best that could be achieved without exposing
apparent conflicts with SR, and perhaps then we'd have a logical
reason why the analyses seem to be so consistently compromised.

If SR is /not/ a correct physcal theory, then perhaps these repeated
screwups make some sort of sense and tell a story.
Otherwise, if SR really is correct, I suppose the explanation would
have to be that the whole community is just hopeless at these sorts of
calculations, period.

:(

I prefer the "heroic" interpretation. :)

=Erk= (Eric Baird)
: " Time is money. Time is not money. "
: " Space and time are interchangeable. Space and time are not interchangeable. "
: " Special relativity is true. Special relativity is not true. "

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