the beautiful explanations in sciences?bypasses the experiments..

Hi all!

Arstotle's stated that two different bodies having different weight
dropped from the same height will do not reach the earth at the same
time but heavier body will reach first.
Probably Aristotle had experimented with taking a feather like body
which doesn't break the air resistance and another heavier body and
hence could had wrongly stated.

But I am more fascinated with the Galileo's explaination to "why any
two bodies dropped from the same height reach the earth at the same
time irrespective of their weight" .(I am putting it in my own words)
"suppost two canon balls having weight 6kg and 3kg (all figures are
mine)dropped from the same height then according the Aristotle their
velocity to reach the earth and hence the time will dependent of the
weight of the balls.The 6kg ball will take half of the time to 3kg
ball.
Suppose 3 kg ball take 30 seconds to reach the earth and hence the 6
kg ball will take 15 seconds.

Now suppost the two balls are tied together and dropped from the
previous height then what will happen.
The 3 kg weight will resist to reach the earth in less than 30 seconds
and the 6 kg will try to reach in 15 seconds .So the two balls'
assembly will reach in (30+15)/2 = 22.5 seconds.
but the assembly has an overall weight of 9 kg and hence it should
reach in 10 seconds(This is all if we take Aristotle's statement to be
correct.)
So the two answer shows a paradox and hence Aristotle's statement is
definitely wrong."

The most interesting part to me in above (of course refering to
Galileo's original explaination) explanaition is it hardly requires
any experiment.
since the mathematical and logical deductions are so intelligent and
complete in themselves that one can get convinced by merely reading
it.
It hardly requires any experiment.

Now I want to know , are their any such beatiful and intelligent
explanaitions in physics which totally eliminates the necessity of an
experiment for their proof?(i.e the explanaitions are complete in
themselves.?)

(I feel that Einstein's explanaition about "why light's speed is
absolute?" is totally a masterpiece of logical analysis. )

Thanking you,


Regards,
arj

Dear ashok:

"ashok" <[Only registered users see links. ]> wrote in message
news:[Only registered users see links. ] m...
....

You are *assuming* proportional action. It could have any relationship to
satisfy Aristotle's criterion, as long as the 6kg landed first.

....

The beauty is in making a prediction, and then *verifying* it with
experiment.

David A. Smith

Now I am confusd ..I was always tought that the balls would hit the ground
at the same time???? we used to be shown this with a feather and a glass
ball in a tube with all the air removed ( Vacuum ) at school both hit the
bottom of the tube at the same time...it is nothing to do with the weight as
it is clearly obvious that the glass ball is much heavier than the feather.

"N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:[Only registered users see links. ]> wrote in message news:<Kp83d.196732$4o.139746@fed1read01>...

Yes..I assumed certain values.


That's true.
But my point was , there are some explaination that are so intelligent
they totally eliminate the need for an experiment.

[Only registered users see links. ] (ashok) wrote in message news:<1dc813f.0409182030.79f99838@posting.google.c om>...

It requires lots of experiments. Since Galileo
not only dropped balls from a tower. He measured
how fast they drop. Otherwise his theory of gravity
would be no different than Aristotles:

Comparative Philosophy (in Italy rather than Greece).









Yes. Euclidean Geometry has no proofs.
All it has is axioms.

"ashok" <[Only registered users see links. ]> wrote in message
news:[Only registered users see links. ] m...

<snip>


Shortest answer: No

Short answer: No, because physics doesn't work that way. The failure of
Aristotelian physics is part of the reason that the scientific method was
developed. The ability of perfectly good logic to lead to a perfectly bad
answer (often because of a perfectly understandable omission) demonstrated
(another *empiricists* word) that natural philosophy needed a more reliable
means of establishing the validity (for practical purposes) of any
statements about the nature of the external world.

Long answer:
A proof that relies on elegant logic is the province of mathematics. Logic
also allows for the possibility that statements can be true, but not
*provable.* See Goedel's Incompleteness theorem.

As David A. Smith has pointed out, physics is an *empirical* science. It
deals strictly with phenomena that are *measurable* (i.e. subject to
independent, replicable, quantitative observations) and tests statements
through empirical means - either the statement is accurate to within our
current measurement uncertainties, or it is not.

Inaccurate statements are discarded, as are the hypotheses that spawned
them, and often the credibility of those who proposed them.

Accurate statements are *conditionally* accepted, and are preserved as long
as they remain useful predictors of the outcome of measurements.

Newtonian gravitation, for example, was accepted almost immediately because
it easily accommodated the planetary orbits that had spawned so many
generations of epicycles in the effort to adjust the Ptolemaic theory to the
data. It was only when the ability to measure the movement of the
perihelion of Mercury demonstrated an inaccuracy in Newtonian gravitation
that people began to worry about it. General Relativity's first successful
test was to predict a value for the precession rate that was within the
observational error of the data.

Still, Newtonian gravitation is used for most celestial mechanics
calculations (asteroid tracking, interplanetary probes and such) because it
is as accurate as the needs of the problem require and it is computationally
much more convenient than the full SR treatment. IOW, Newtonian gravitation
is *practically* correct.


Tom Davidson
Richmond, VA

ashok wrote:

It is unclear that the Equivalence Principle is true. Einstein
postulated it for General Relativity and metric gravitation (his
elevator Gedakenexperiment), hence spacetime curvature. Weitzenboek
ignored it and got exactly the same predictions qualitatively and
quantitatively in affine gravitation with spacetime torsion inside
wildly different maths. They can't both be correct though the answers
are identical.

All chemical compositions empirically fall identically in vacuum, now
good to one part in five trillion difference/average,

<http://wugrav.wustl.edu/people/CMW/update98.pdf>
<http://www.astro.northwestern.edu/AspenW04/Papers/lorimer1.pdf>
Equivalence Principle testing
<http://www.npl.washington.edu/eotwash/pdf/prl83-3585.pdf>
[Only registered users see links. ]
Nordtvedt Effect
Physics Today 57(7) 40 (2004)
No aether and Lorentz Invariance.

However, all models of gravitation are geometries that never consider
composition. The proper test of spacetime geometry is test mass
geometry. We'll know by Summer 2005 if Einstein is validated or
falsified. The proposal in the pdf below is being run in China. One
if its nasty predictions is that the shape of an object - the
divergence of its three moments of inertia - makes a difference. That
directly contradicts Galileo's reasoning.

Since no parity test masses (of identical chemical composition, too)
have ever been observed, it could go either way. There are no prior
observational constraints at the measurable magnitude of parity
violation at the current minimal level of detection of 10^(-13)
difference/average. Calorimetric constraints make it highly unlikely
for a parity anomaly to be bigger than 100x10^(-13). It's a nice
neighborhood to be visiting.

IT REQUIRES EXPERIMENT.

--
Uncle Al
[Only registered users see links. ]
(Toxic URL! Unsafe for children and most mammals)
[Only registered users see links. ]

ZZBunker wrote:

[snip]

Galileo used inclined planes and pendulums to investigate the
Universality of Free Fall as it was called. The Leaning Tower of Pisa
experiment is possibly apochryphal. In any case, it has serious
deficiencies including what "simultaneous" means when you have no
timing device accurate for the possible differential; air resistance,
etc.

The Equivalence Principle has been a popular topic of study and
commentary,

[Only registered users see links. ]

continuing to this day (Eric Adelberger, Jun Luo, Riley Newman,
Wei-Tou Ni, etc).

--
Uncle Al
[Only registered users see links. ]
(Toxic URL! Unsafe for children and most mammals)
[Only registered users see links. ]

[Only registered users see links. ] (ashok) wrote in message news:<1dc813f.0409182030.79f99838@posting.google.c om>...

Aristotle has the abstract objective form as the
required reading style. You read it in predicate.

The example you use is to prove by absurdity the opposite.