Hobba's misconceptions

here you go:

http://groups.google.com/group/sci.physics/msg/1694d44358577f35

and I quote his gem (another one):

"Newton's First Law contains implications about the fundamental
symmetry of
the universe in that a state of motion in a straight line must be just
as
"natural" as being at rest. If an object is at rest in one frame of
reference, it will appear to be moving in a straight line to an
observer in
a reference frame which is moving by the object. There is no way to say

which reference frame is "special", so all constant velocity reference
frames must be equivalent.'

Thus, contrary to your irrational assertions that classical mechanics
requiring an absolute frame, Newton's first law in fact asserts the
opposite. What classical mechanics has is the notion of absolute time.
"

end quote

Now, Hobba seems to have never understood Newtonian mechanics (amybe he
never took a course). In fact, Newton's famous backet experiment was
about showing that there is an absolute frame of reference. Hobba does
not understand that when curvilinear motion comes into play, his silly
argument breaks down. Consider the following REAL experiment, not the
type of though experiments he has been brainwashed with:

On a rotaing disk there is a spring attached to its center and a steel
ball attached to its other end, resting on the disk. When we start
rotate the disk uniformly, the spring extends by a small distance
delat(x). The ball now is at rest in its own frame of reference.
According to Hobba:

"If an object is at rest in one frame of reference, it will appear to
be moving in a straight line to an observer in a reference frame which
is moving by the object. There is no way to say
which reference frame is "special", so all constant velocity reference
frames must be equivalent.'

Well, I will tell you which frame is special. For a stationary observer
in the room the disk is located, the for e registered by the spring is
equal to the centripetal force that keeps the ball in circular motion.
But in the disk frame, it is at rest although there is a force measured
by the spring. This means, contrary to the knowledge you have acquired
by various web pages, that the laws of motion (which you do not
understand) must be applied in the right frame. And this was exactly
Newton's point. In order to explain how come the ball is at rest in its
own frame while there is a force on it, a ficticious centrifugal force
must be considred. Newton said: "Ficticious forces arise because of the
applications of the laws of motion in the wrong reference frame". What
is the correct reference frame? It is absolute space. Now, everybody
knows this, but you do not. This is because, all your knowledge comes
from the web.

Thus, kinematically (that is probably the only introductory course
Hobba took) all constant velocity frames are equivalent. But when
forces come into play, in Newtonian Mechanics the second can be applied
only wrt an absolute frame of reference.

The conclusion is that Hobba is a very confused fellow who plays
relativity expert but he does not understand that from the first law of
Newton, which does not require a special frame, he cannot claim the
same when forces come into play. Actually, LEX PRIMA (first law) is
about the fact that relativity of motion applies only in kinematics but
when forces come into play as in LEX SECUNDA (second law), relativity
breaks down and the notion of an abslute space comes in. This is
exactly what Mach tried to challenge and Einstein failed to incorporate
his views in GR and as a result, GR HAS AN ABSOLUTE SPACE-TIME wrt
which deviations from geodesic paths must be referenced.

Mike

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