**4 - Vector Analysis for Bodies or Particles of Matter**

**"**The whole of science is nothing more than a refinement of everyday thinking**"** - Albert Einstein ( 1879 - 1955 )

**"**Whence arises all that order and beauty we see in the world?**"** - Issac Newton, Opticks ( 1643 - 1727 )

**"**The only thing that interferes with my learning is my education**"** - Albert Einstein ( 1879 - 1955 )

**The Problem**

It's an accepted á priori postulate of all types of physics ( Galileo, Newton, Einstein's Special and General relativity ) that the form of all of these mathematical physics laws maintain the same invariant form in all reference frames, whether inertial ( non - accelerating ) as in Special Relativity or the more generalized non - inertial frames ( accelerating ) as in General Relativity.

So it was earlier stated in regards to Special Relativity, the following:

** The Principle of Special Relativity** - All the laws of physics in their simplest reduced form are Lorentz - transformable and hence form - invariant as between an infinite number of moving reference systems, each one of which is moving uniformly and rectilinearly with respect to any other system and where no one system is privileged or preferred over any other inertial reference system when measurements of length or time are taken.

However as Einstein proceeded into his General Theory wherein he was dealing with accelerating ( non - inertial ) frames of reference in addition to those of his previous Special Theory, it became necessary for him to propound his __General Covariance Principle of Relativity__ or simply __The General Principle of Relativity__:

** The General Covariance Principle of Relativity** - All the laws of physics whether manifested in inertial ( special relativity ) or non - inertial ( general relativity accelerating ) frames, are form - invariant as regards the Lorentz transformation equations expressed as valid covariant tensors where in the presence of bodies of matter possessing mass the geometry of spacetime becomes geodetic or curved, otherwise identified as

**"**The laws of physics must be of such a nature that they apply to systems of reference in any kind of motion**"**

- The Foundation of the General Theory of Relativity, 1916, by A. Einstein

So the problem is that in the case of ordinary - space coordinates for time and velocities, nothing really is Lorentz form - invariant especially as regards time and velocity, all of which will be overcome by enlisting proper time first and foremost in all future special and general relativity equations regarding time, velocity, energy, momentum and acceleration for the motion of bodies of matter possessing mass along world timelines in four - dimensional space and time.

**Analysis**

**§ Define:**

**§ Lorentz transformations in - space:**

However in - space where the invariant properties of space - time are invoked under Lorentz transformation equations, we get

Namely that in Euclidean - space, nothing is Lorentz time - invariant and hence in violation of the Principle of Relativity for form - invariance of the equations of special and general relativity physics!

**§ Normalization with The Lorentz ( Correction ) Factor:**

That is, with the extra help from the Lorentz ( correction ) Factor, the Euclidean - space can be brought into - space compliance under invariant Lorentz transformations by simply utilizing proper time instead of spacial or coordinate time!

**§ The Light Sphere and Invariant Proper Time :**

Of course all of the pseudo - Euclidean, Minkowski special relativity equations ultimately derive from the *form - invariant light sphere equation* under Lorentz transfomation:

where

for which

See chapter: **"**Minkowski's Space - Time Light Cone**"**

**The Solution**

But all of the above - and - space inconsistencies are brought into invariant Lorentz transformation compliance simply by invoking the Lorentz form - invariant proper time where

**The 4 - Velocity Vector**

**§ Defining World Timeline Coordinates:**

**§ Velocity over a world timeline path:**

**§ Defining the 4 - Velocity Vector:**

and for which is the 4 - velocity vector tangent to the World Timeline path of the body or particle of matter in motion possessing mass, thereby satisfying the Lorentz transformation equations for invariance ( of proper time and invariant distance intervals on the surface of an ever expanding light sphere ) between relatively moving , systems:

**§ Corollary:**

__Case 1__: material body of matter possessing mass:

__Case 2__: zero rest mass, wave - like particle ( photon or graviton ), where :

This is a __null 4 - velocity vector__ which is also __invariant__ with respect to proper time .

That is, in Case 2 we can now identify the null 4 - velocity vector for light photons comprising a sphere of light such that

where the invariant space - time distance separating light photons on the surface of an ever expanding sphere of light has *zero length* !

**The 4 - Momentum Vector**

**Massless Photons**

**To the point:** * only light and gravity are pure energy* !!

**The 4 - Acceleration Vector**

Please note: for the 4 - Acceleration Vector mathematical analysis it's necessary to gain some expertise of the General Relativity parts of this relativity mathematical science essay.

**The 4 - Force Vector**

Again please note: for the 4 - Force Vector mathematical analysis it's necessary to gain some expertise of the General Relativity parts of this relativity mathematical science essay.