ueb wrote:


So ? Do you mean that seriously and honestly ?
Please tell me what you mean with "sound on empirical grounds" ?
How do you take a theory that meets all observations (up to now),
and additionally lets see known particle numbers ?

There has to be some indicative evidence that the theory might be true.
A new theory should be able to predict any valid prediction given by an
older theory.

To the best of my knowledge all new theories have been proposed to
either account for a phenomenon not adequately handled by older theories
(for example quantum mechanics) or to clean up a lack of symmetry in
existing theories (special theory of relativity which made mechanics and
electrodynamics live together in harmony).



I know that physicists are enraged if an engineer dares to propose
such theory (even worse: supply with evidence), but would like to
hear _your_ opinion.

If someone has a theory that explains phenomena currently not accounted
for, has experimental support and is not yet falsified, I am all ears.

Bob Kolker

"robert j. kolker" wrote in message ...
Paul Draper wrote:


Alternative-theory flamers: the onus is on you to point accurately to the
failing of the theory.

The burden of proof of a theory lies squarely on the one proposing it.

Bob Kolker


This is true, which I also attested to in my post. But it's not that
simple. Science is, by nature, a community process. Every theory must
be checked against independent experimental confirmation. Most
experimental results must be repeated by an independent measurement
before becoming completely accepted. Consequently, the critique of new
physics needs to abide by some solid sociological rules, as well. It's
just as important that criticism of a new theory point correctly and
cleanly to the SCIENTIFIC flaw.

Part of the reason for this is that the temptation to dismiss a new
model because it conflicts with prevailing wisdom is exactly what will
make the critic a poor scientist him/herself. For whatever barriers
you impose on others you will impose on your own mind, and if those
barriers are misplaced, you may miss something crucial.

PD

"robert j. kolker" wrote in message
...


Bill Hobba wrote:


Does it have to consistent?

Yes. Ex falsi quodlibet. From an inconsistent set of postulates any well
formed statement can be inferred.

It is not that simple Bob. Theories with obvious inconstenticies would not
be proposed by competent people in the first place. But what about more
subtle ones? -such as my often quoted example of the Dirac delta function.
Under Lebesque integration is it an inconsistent function yet was used for
yonks by applied mathematicians no problemo. Exactly what was going on was
eventually sorted out - but up until that point should we have dismissed the
results thus obtained? No. What we should have done is exactly what did
occur - we continue with the theory and see if the blemish can be fixed up -
which it was. But what decides if an inconsistancy is merely a blemish that
can be fixed up or something much more serious - all I can suggest is it
need to be looked at on a case by case basis. But I suspect that most often
it will be found to be of the blemish type and we can continue using until
it is fixed up.

Thanks
Bill


Bob Kolker

Ian Stirling wrote:

In sci.physics Uncle Al wrote:
snip
Religion and politics are based upon absolutes and faith. They will
always fail - bloodily dragging their adherents down with them.

Religious theries are not inherently less testable than physical ones,
as long as there is some divergance of religeous theory and the
predictions made by science.
If you hold that in 2020, there will be an anomolous ratio of
hydrogen/duterium/tritium evaporating from comet X as it hits periapsis,
and I hold that in 2020, the world will be painted a subtle shade of purple
by God, both are equally testable.

Something that's been missed is that the person doing the testing
has to be able to report back.

Belief in the afterlife is hard to prove - unless it turns out that
ghosts have just been awaiting the development of suitably sensitive
etevos balances to communicate through.

We lock and load the fist hemiparity Eotvos experiment next week. If
I were Einstein's shade I'd be sweating it - Uncle Al played the
violin.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf

On Thu, 30 Sep 2004 18:16:47 -0400, robert j. kolker wrote:

Maleki wrote:

Tell me, in USA, are Chicanos better scientists or your ilk?
How come they're successfully and firmly moving on to erase
your asses off this planet then.

Because our cowardly traitorous politicians are letting it happen in the
name of Democracy and Diversity. If the Smart People of this country do
not take power we are in for a wide world of Pain.

Bob Kolker

Believe me, the politicians don't have a better choice. It
is too late! It was too late a long time ago. One must just
start to respect others, that's all there's left to do. A
lot of smart and intelligent people are thinking this out
and nobody has a solution.

--

alAje vAghe'e pish az voghu' bAyad kard
darigh sud nadArad cho raft kAr az dast

"Paul Draper" wrote in message
om...
| "robert j. kolker" wrote in message
...
| Paul Draper wrote:
|
|
| Alternative-theory flamers: the onus is on you to point accurately to
the
| failing of the theory.
|
| The burden of proof of a theory lies squarely on the one proposing it.
|
| Bob Kolker
|
|
| This is true, which I also attested to in my post. But it's not that
| simple. Science is, by nature, a community process. Every theory must
| be checked against independent experimental confirmation. Most
| experimental results must be repeated by an independent measurement
| before becoming completely accepted. Consequently, the critique of new
| physics needs to abide by some solid sociological rules, as well. It's
| just as important that criticism of a new theory point correctly and
| cleanly to the SCIENTIFIC flaw.
|
| Part of the reason for this is that the temptation to dismiss a new
| model because it conflicts with prevailing wisdom is exactly what will
| make the critic a poor scientist him/herself. For whatever barriers
| you impose on others you will impose on your own mind, and if those
| barriers are misplaced, you may miss something crucial.
|
| PD
Kolker has the remarkable ability to say all the right things but does not
follow his own advice. The only appropriate word to describe this
phenomenon is "hypocrisy".
Androcles

"robert j. kolker" wrote in message ...
Bill Hobba wrote:


Does it have to consistent?

Yes. Ex falsi quodlibet. From an inconsistent set of postulates any well
formed statement can be inferred.

Since not everyone may be familiar with this, first a digression on logic to
show why this is so.

Let p and q be True/False propositions. What T/F proposition is equivalent
p = q ? Well, when p = q is true, it can't be the case that p is true and
q isn't. This motivates:

(p = q) = ~(p and ~q)
= (~p) or q

Now suppose we have a formal axiom system that is inconsistent, i.e, there is
a proposition b such that both b and ~b are true in the system. Consequenrly,
(b and ~b) is also a true proposition. Let c by any proposition in the system,
and consider

[(b and ~b) = c] = ~(b and ~b) or c
= (~b or b) or c

But (~b or b) always true gives [(~b or b) or c] always true, which in turn
gives [(b and ~b) = c] always true. Now (modus ponens) [(b and ~b) true gives
c true.

c was arbitrary, so any well-formed statement can be inferred in an
inconsistent system!

However, I have never seen any physical theory laid out as a formal axiom
system. And if a physical theory were laid as out as a formal system it surely
would be sufficiently complicated as to include Peano's axioms for the natural
numbers. Thus, by Goedel's second incompleteness theorem, it would not be
possible to demonstrate the logical consistency of the physical theory.

Also, I think physicists use the term "consistent" to mean something different
than do logicians. I'd like to see people in the group take stabs at defining
(losely) what it means for a physical theory to be consistent.

Take quantum electrodynamics (QED) as an example. Many physical results in QED
are calculated using what are thought to be divergent (even after
renormalization) asymptotic series.

1) Is QED a good theory?

2) Is QED a consistent physical theory?

I think most mainstream people would answer "Yes." to 1), but the answers to
2) might include phrases like "domain of applicability."

Regards,
George

"robert j. kolker" wrote in message ...
RP wrote:


IOW, he should provide a test of the theory, one that distinguishes it
from existing theory.
Suppose, however, that the differences in predictions are much smaller
than the available experimental precision?
The onus is once again on the opposition.

Not at all. If the theory cannot be tested, it should be put away in a
drawer until it can. Of course if someone falsifies the theory in the
mean time, the matter is settled.

In general, theories that cannot be tested are worthless. By that I mean
if a theory does not produce a testable quantitative asertion it is
vapor. It has no standing.

Bob Kolker

In a sense, this is right. The trick is finding the point when it
should be put away in a drawer. A number of theories (M-branes, spin
network TOEs, supersymmetry come to mind) show enough *theoretical*
promise that folks want to work on it a while until they can get to
the point where an experimental prediction can be calculated. Usually
the problem is that 1st-order effects may be out of range of
experiment, but 2nd- or 3rd-order effects (which are only understood
once the 1st-order effects are calculated) might be more accessible.

Again, it is tricky to dismiss a theory out of hand, without risking
prejudicial blindness.

PD

"richard miller" wrote in message ...
In general, theories that cannot be tested are worthless. By that I mean
if a theory does not produce a testable quantitative asertion it is
vapor. It has no standing.

Bob Kolker


This is a key point.

I have had to sit at parties, gunned down by ghost believers, god squaders,
everyone with a belief - they all believe scientists are closed minds who
cannot see it. So I say to them "yes you can believe, you can have a theory
but you must produce something predicatable, something everybody can say yes
this theory does indeed reproduce, time and time again, events, results that
were once thought bizarre, but now completely explained". Of course they
never can. 'My brother once saw this', 'my Aunt is convinced', 'my Uncle has
a perpetual motion machine that generates all his energy needs' - but will
never show you this device or reconcile that with his monthly energy
payments!

I say to them, believe in what you want, but if you cannot predict anything
with it, it is worthless. Absolutely worthless. They never can, it is all
one-off anecdotes.

Incidentally, they never explain why ghosts go through walls, but don't fall
through the floor. I guess Ghosts don't feel the gravitational force.

'God moves in mysterious ways'.

In other words, we haven't a bloody clue - but we do have this golden waiver
card (get-out clause), if we can't explain it, we just wheel out this old
tosh.

To re-quote Dr/Prof/Mr/Kolker

if a theory does not produce a testable quantitative asertion it is
vapor. It has no standing.


Richard Miller

Let's be careful here. It could be that folks are just citing
*observations* that have no current basis for explanation. You don't
have to resort to ghosts or miracles to find those. Why are there
three generations of quarks? Why don't photons couple to the Higgs and
gain mass? What is the source of CP violation? What is the source of
the cosmological constant? There are zillions of things that we don't
understand.

"Ghosts" as such are not an explanation -- they are a recognition of
phenomena outside our understanding. As such, they should be relished
and pursued, just as much as the hundreds of millions of Euros
invested in finding the Higgs.

PD

"Bill Hobba" wrote in message ...
"Paul Draper" wrote in message
om...
I'm writing this just to set a line in the sand for both alternate-theory
posters and to those who respond to those posters. All too often,
pyrotechnic rhetoric gets in the way of a very simple evaluation.

1. A good theory has to refer to well-defined terms and concepts. It does
no
good to exploit the softness of common language to fuzz the boundaries of
words. If you say "waves" and you don't mean everything that is included
in
the definition of a wave as physicists define it, then provide a careful
and
complete definition of your own, being sure to explicitly exclude the
conventional connotations that don't apply. It's not necessary to adopt
the
same language and concepts from historically accepted physics terminology.
If it were so, we would have not come to understand "rest mass",
"invariant
interval", "branes", "black holes", or "quarks". But it IS important to
define carefully what you mean.

Sure.


But this isn't enough.

2. A good theory has to be self-consistent. That is, it can't predict
something that is counter to another prediction, or can't predict
something
that is counter to one of its assumptions. It is not necessary that it be
consistent with assumptions and predictions of other theories. If it were
so, we would not have accepted the relativity of simultaneity. But it IS
important to check that the theory is coherent.

Hmmmmm. It is not so simple. For exmaple use of the Dirac delta function
was inconsistent before they developed distribution theory. Like so many
things in science hard and fast rules are difficult to come by. Again
linearised gravity has at least one inconsistency and yet accounts for quite
a few phenomomena.

Fair point. The same could be said for gauge theories before their
infinities could be calculated away in renormalization schemes. A good
theoretician will point out those dust bunnies and confess where there
are potential problems that could doom the theory. If they get worked
out, great. If they don't, flush.



But this isn't enough. All too often, theorists come up with a model that
is
pleasing to the eye and self-consistent and think that those virtues alone
make it appealing.

3. A good theory has to *qualitatively* account for all existing
observations and experimental results that pertain to its domain. A theory
that is patently inconsistent with a known result MUST be summarily
discarded, no matter how well 1 and 2 are satisfied. It is not necessary
that the underlying explanation agree with pre-existing theoretical
explanations. If it were so, we would would have dismissed special
relativity. But special relativity did not violate any hitherto observed
behavior at low velocity, and there were therefore no good reasons to
dismiss it on those grounds.

I would agree with that.


But this isn't enough. A plausible explanation does not substitute for a
real calculation. And this, unfortunately, is where most of our amateur
theorists with alternate theories come to a grinding halt.

Too true.


4. A good theory has to *quantitatively* account for all existing
observations and experimental results that pertain to its domain. This is
where mathematical underpinnings start to become required. You can't make
a
quantitative calculation of a behavior that can be measured without the
mathematical representation of the theory. It is not important that the
model agree with the form of the equations and formulas of other theories.
If it were so, then the Copernican model of the solar system would not
have
supplanted the earth-centric epicycle model. But if the Copernican model
had
not been able to CALCULATE the position of the planets in the sky as well
as, or better than, the epicycle model, then it would not have mattered
how
well 1 and 2 and 3 were satisfied.

Sure.


But this isn't enough. There may be dozens of completely equivalent models
that adequately describe the same known phenomena, both qualitatively and
quantitatively. If this is all a theory does -- match evenly against an
existing model -- then it is no good. Here again is where many
"alternative
interpretations" fall flat.

5. A good theory has to *quantitatively predict* an observable behavior
that
has not yet been measured, and preferably a behavior that is at odds with
the predicted behavior of other proposed theories. If it fails to predict
anything new, then it must be dismissed as a theory, no matter how well 1,
2, 3, and 4 are satisfied.

If however it is more elegant and appealing then it might be better. Eg SR
and LET make exactly the same predictions in their domain of applicability.
It is not because of 1, 2, 3 or 4 SR is preferred - it is because it is
based on what physicists have discovered is a very important aspect of
nature - symmetry - see Tom Roberts admittedly ancient post
http://www.google.com/groups?selm=38...D%40lucent.com.

This is a remarkable statement and entirely true, and reflects the
*humanity* of science. In many endeavors in science now, we not only
weigh competitive models by virtue of their underlying simplicity and
elegance, but we also actively and hotly pursue models on the FAITH
(and I am using that term in the broadest, most inclusive sense) that
the underlying truth is even more simple and elegant than what we
currently understand. An example of this is the confrontation with
three generations of quarks and leptons, followed by a scowl and a
completely unfounded assertion that "That can't be it," followed by
serious attempts at a preon model that would account for three
generations. Another example is looking at U(1)xSU(2)xSU(3) symmetry
and chasing a GUT with SU(5) symmetry. This is quite literally
stepping out in faith, a feeling in the gut that there must be
something more, something simpler, something more beautifully made.

This is not to say that elegance and simplicity should be confused
with intuitiveness. Most of the great leaps have been ones that have
favored simplicity and elegance over deep-seated prejudices.
Abandoning space and time for spacetime is an example. Abandoning
gravitational acceleration for motion on a straight line in curved
space is another. The holographic principle is another.


If Einstein had written general relativity, but
he had failed to make the verifiable prediction that the apparent location
of a star would shift so many arc-seconds during an eclipse, then it would
have been a worthless theory.

Not necessarily - it would have been more in line with the experimental
evidence of SR eg Newton's theory predicts instantaneous action of gravity
something verboten in SR - GR does not.

To pick nits, I would argue that this would have confirmed SR, but not
led to acceptance of GR.


In this sense, most of the string models and
spin-network models of the universe are NOT good theories yet, because
they
fail to make a verifiable prediction.

Here is where we get to the rub. If what you say above is true why are they
being pursued and what makes it legitimate science? It has to do with the
attitude of those doing it - they worry about the above. That is the key
thing and what makes it science.

I responded to this in a different post. In a nutshell, it's tricky to
know when to let go of an idea. Sometimes, it does take time to
develop a theory well enough that experimental predictions become
accessible. And this is an interesting sociological event -- a model
in early development is more a team recruitment effort than the
establishment of the validity of the theory. I would argue that, until
a model has been developed to the point where verifiable predictions
start popping out of it, it is a theory-larva, a model, a
work-in-progress, but not yet a theory, if such labels are required.


In this sense, even the Standard Model
with the Higgs boson is not a very good theory yet, because one of its
primary verifiable predictions (the Higgs boson) has not been confirmed
yet.

Not quite true - the standard model includes QED which is the most
accurately experimentally verified theory of all time. One must look a the
theory as a whole to form an opinion.

Again, I look at the Standard Model as an extension of QED that
includes a mechanism for explaining the electron's mass, which QED
does not. QED is fine but has an open and acknowledged hole, and the
proposed hole-filler has not yet been verified.



Alternative-theory-proposers: the onus is on you to make sure your model
satisfies ALL FIVE of the above requirements. If it does not, then the
world
has a complete right to summarily dismiss your conjecture.

I do not agree.


Alternative-theory flamers: the onus is on you to point accurately to the
failing of the theory. Inconsistency with existing, verified *theories* is
not a valid critique. For example, it is improper to discount a theory
because it disagrees with Dirac's equation or because it violates a
postulate of GR.

Not quite true - if that posusulate has experimental support then it is
proper to discount it. But point taken - correspondence with experiment is
the criteria and ability of the theory to make predictions.

I would cite the Newtonian postulate that time is an immutable
dimension independent of space. At the time that SR was proposed,
there was *no* experiment evidence that countermanded this. Albert's
great leap was to discard the Newtonian postulate even though there
didn't seem to be anything wrong with it experimentally, propose
something simpler but conceptually much different, and then say, "If
you look *here*, you will see for the first time that I am right and
Newton was wrong."


It IS proper to point to an experimental observation which
an existing theory gets correct and the proposed model does not (steps 3,
4
and 5 above). It is improper to discount a theory because the proposer has
not calculated your favorite observable. It IS proper to point out that
the
proposed theory either doesn't have the mathematical equipment to
calculate
your favorite observable, or that it does but the calculation results in
something contrary to what's actually seen.

Still a very good post.

Thanks
Bill


PD