🚀 go-pugleaf

Could you please help me with what is wrong with these formulas and the way
 they are being used?
 I am not into mathematics and, unfortunately, everytime I see a formula, my
 eyes glaze over.
 I know the argument the person is expressing is wrong, but I cannot argue
 with is formulas although
 I suspect they are being either misapplied or mistated.

 I am especially interested in his claim that:
 "Simple Proof that Nothing Can Move in Spacetime
 Why is motion in spacetime impossible? It has to do with the definitions of
 space and time and the equation of velocity v = dx/dt. What the equation is
 saying is that, if an object moves over any distance x, there is an elapsed
 time t. Since time is defined in physics as a parameter for denoting change
 (evolution), the equation for velocity along the time axis must be given as
 v = dt/dt which is self-referential. The self-reference comes from having
to
 divide dt by itself. dt/dt always equals 1 because the units cancel out.
This is of course meaningless as far as velocity is concerned."

 Please reply to:  rbennet9@tampabay.rr.com.

 Thanks in advance for your help.

 --------------------


 One Sentence Proof #1
 Moving in spacetime is impossible because it requires motion in time and
 motion in time is self-referential.

 One Sentence Proof #2
 Moving in spacetime is impossible because an evolution parameter (time)
 cannot be its own evolution parameter.


 Simple Proof that Nothing Can Move in Spacetime
 Why is motion in spacetime impossible? It has to do with the definitions of
 space and time and the equation of velocity v = dx/dt. What the equation is
 saying is that, if an object moves over any distance x, there is an elapsed
 time t. Since time is defined in physics as a parameter for denoting change
 (evolution), the equation for velocity along the time axis must be given as
 v = dt/dt which is self-referential. The self-reference comes from having
to
 divide dt by itself. dt/dt always equals 1 because the units cancel out.
 This is of course meaningless as far as velocity is concerned.

To emphasize, it is logically  impossible for the t coordinate of an object
to change because such a change is self-referential. Et voil�! It is that
simple. No time travel, no motion in spacetime, no spacetime and no time
dimension. They are all abstract mathematical constructs without any
counterpart in nature.



 [You may skip this part if you want to. It does not add to the proof
against
 motion in spacetime. I just use a little math notation for those who are so
 inclined.]

 The above explanation can be rephrased using simple 4-D spacetime manifold
 math. If the world-line (a path in spacetime) of a moving particle is
 parameterized thus:

  (t,x(t),y(t),z(t))

 we can obtain the "4-velocity" of the particle:

 (1,dx/dt,dy/dt,dz/dt)

The t-axis or time-axis velocity component is 1, a dimensionless number.
Now
there are relativists who will insist that it is perfectly acceptable to
express velocity in time with a dimensionless number but the rest of us
with
our head on our shoulders, know that it is not true. We know that a
dimensionless number such as 1 has absolutely no meaning in as far as
expressing velocity or any sort of change. Velocity must be given in units
of velocity such as meters per second or whatever standard units are being
used. For this reason, there is no motion in spacetime.

[I receive emails from people who insist that there is nothing wrong with
saying that motion in time occurs at the rate of 1 second per second. First
of all, dt/dt does not equal 1 second per second. The units cancel out.
Second, dt/dt is always the same (1) regardless of the actual rate of
velocity.]

Note that I put 4-velocity in quotes above. This is because it is not a
velocity at all since nothing can move in spacetime. There is only
3-velocity in 3-D space: (dx/dt,dy/dt,dz/dt), t being a mere evolution
parameter. True 4-velocity (dw/dt,dx/dt,dy/dt,dz/dt) would require a 4-D
manifold having 4 spatial dimensions and no time dimension. Now that is an
interesting idea, four spatial dimensions, an idea I certainly would not
object to. But time travel? Absolutely not!

One of the amazing things about this time travel business is that a position
in spacetime is usually represented by (ct,x,y,z). What this means, is that
every second a body moves exactly 299792458 meters, or a light-second in the
fourth dimension. (This tool is convenient in explaining what is called a
particle's light cone because it allows the sides of the light cone to slope
at 45 degrees.) However, note that, using this convention, the fourth
dimension is no longer a temporal dimension but a spatial one. Why? because
ct resolves to meters, not seconds. Does this means that time travel is
suddenly allowed? Of course not since c is a constant and t is invariant. It
is just that most relativists cannot bring themselves to the point of
accepting a fourth spatial dimension.

There is an unyielding mental barrier that I am still in the process of
identifying. I wonder if it is just intellectual inertia or a vestige of the
historical origin of relativity, kind of like the way an atom is not really
an atom in the literal sense of the word. Still, it is no excuse to conjure
up all sorts of voodoo nonsense and retard progress in our understanding of
gravity for close to a century.

Note: the representation of a position in spacetime is conventionally given
by (ict, x, y, z) where i is the square root of -1, an imaginary number.
However, this is a mere detail, one which does not take away from the
changeless nature of spacetime.