Re: Why

In message <slrnd4m7ih.btn.dubious@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, Bilge <dubious@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> writes 
John Kennaugh:
>Bilge writes

>>  Actually, I know a good bit about both, although I know more about
>>physics than mathematics.
>
>You do not seem to understand the difference.

 Sure I do. Math is any physics that you don't understand.
Your handicap is not my handicap.

>I have a computer program which predicts the height of the tide. It is
>an accurate mathematical model.

 There's no such thing as an accurate model of a physical
system that doesn't contain physical input.

>It accurately predicts physical things
>but being able to use it does not mean I understand the physics.

 I'm sure that you don't. But I'm not you. If I don't understand
how a program models something, I don't use it until I do understand
it.

>For that one has to understand the causality. The water does not go up and
>down because the maths says so.

 Nice of you to discover what physicists have known all along
and have employed in developing physical theories like relativity
and relativistic quantum field theory. That begs the question of
why you are telling me this, unless you just had to announce your
discovery to the world.

>As the program works one might assume
>that whoever wrote it had a proper understanding of the physics although
>there is a remote possibility that he had a misunderstanding and still
>ended up with something which works.

 And if someone sat down with nothing but a pile of transistors resistors,
inductors, capacitors, some solder and a soldering iron, he might solder
them together and have a working tv set without understanding what he is
doing. But, by employing a bit of common sense, I can also guess the
chances of that happening.

>To take a classically familiar example, in times past the motion of the
>planets across the night sky could be described to any desired degree of
>accuracy on the basis of the Earth being the dynamic centre of the
>universe. A better understanding came by questioning the underlying
>assumptions and simplification achieved by means of a Sun-centred
>theory. This surely demonstrated the importance of being able to
>recognising and being able to question the underlying assumptions of any
>theory.

 Unfortunately, you have no idea what the physical importance was,
since that pointed the way to relativity.

>Relativity is a principle theory - a mathematical model.

Bzzzzt. Bull*** detected. Slogans aren't arguments. 

It isn't a slogan I was quoting Einstein.

"We can distinguish various kinds of theories in physics. Most of them are constructive. They attempt to build up a picture of the more
complex phenomena out of the materials of a relatively simple formal scheme from which they start out.... When we say that we have
succeeded in understanding a group of natural processes we invariably mean that a constructive theory has been found which covers the
processes in question. Along with this most important class of
theories there exists a second, which I will call "principle-theories." These employ the analytic, not the synthetic, method. The elements
which form their bases and starting-point are not hypothetically constructed but empirically discovered ones, general characteristics of
natural processes, principles that give rise to mathematically formulated criteria which these separate processes or the theoretical
representations of them have to satisfy. The advantages of the constructive theory are completeness, adaptability, and clearness,
those of the principle theory are logical perfection and security of the foundations. The theory of relativity belongs to the latter class."
Einstein, Ideas and Opinions, Three Rivers Press, p. 228-9.

For that reason,
the rest is ignored.


Invalid reason for ignoring it then.

You may note that Einstein states that "The elements which form their [principle theories] bases and starting-point are not hypothetically constructed but empirically discovered ones." However there was no empirical basis for relativity because there was no empirical evidence for source independence. That was simply a belief based on a belief in the ether. No other causality has been suggested. You try and claim that the maths which has evolved from that assumed causality is actually the cause and you expect me to take you seriously.

The original ether theory failed to predict the result of MMX. Lorentz came up with a fix - interaction between matter and the ether - The Lorentz transforms - which you still use and swear by. Lorentz's theory said that light travelled in the ether (so was source independent) at c but because of the transforms it appeared to every observer that he is stationary w.r.t the ether.

Einstein's starting point was unashamedly Lorentz's theory. That is why he assumed source independence. His aim was not to get rid of the ether but to achieve symmetry. He in effect assumed that every observer's relationship with the ether is the same. That it not only appeared to every observer that he is stationary w.r.t the ether but that he IS stationary w.r.t the ether. That is what is implied by the second postulate. That works mathematically but cannot be interpreted in terms of physical causality. Mathematically you assume each observer has his own ether which he is stationary w.r.t - which you call his FoR. Light propagates everywhere in his ether/FoR at c because he is stationary w.r.t it. It is independent of the speed of the source because it is propagating in his ether/FoR.

All your answers may be summed up as "the maths say.......". Where is the physical causality? I am not talking about predicting physical results. My computer program will predict physical tides. The causality for my tide program is the motion of the earth, the moon and the sun and a mysterious, but demonstrable force we call gravity acting upon the ocean which in turn acts upon the land mass.

A FoR is a mathematical abstraction the only physical thing defining it is the observer who's FoR it is. The physical space it defines is according to you devoid of ether. i.e. has no physical substance which can have a causal effect on the light so you are left with the absurdity that the only physical thing which can cause light speed to be constant w.r.t the observer is the observer himself.

It is important to be able to recognise and to be able to question the underlying assumptions of any theory. Einstein's assumptions were that light propagated IN something so its speed is source independent and that the universe is naturally symmetrical i.e. the PoR. Your underlying assumption is that universe complies with the maths which evolved from Einstein's assumptions while rejecting his key assumption.

--
John Kennaugh
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