In 1897 Henri Poincare suggested the possibility of mass observer invariance coming within the realms of special relativity in his paper The Relativity of Space:

 

Suppose that in one night all the dimensions of the universe became a thousand times larger. The world will remain similar to itself. . . . Only, what was formerly a metre long will now measure a kilometre, and what was a millimetre long will become a metre. The bed in which I went to sleep and my body itself will have grown in the same proportion. When I awake in the morning, what will be my feeling in face of such an astonishing transformation? Well, I shall not notice anything at all. The most exact measures will be incapable of revealing anything of this tremendous change, since the yard-measures I shall use will have varied in exactly the same proportions as the objects I shall attempt to measure. In reality, the change exists for only those who argue as if space were absolute. If I have argued for a moment as they do, it was only in order to make it clearer that their view implies a contradiction. In reality it would be better to say that space is relative. (p.1).

 

            Over a century ago, Poincaré used an example of a one-night change in dimensional size a thousand-fold (with symmetry maintained) to demonstrate an extremely important expanded concept in special relativity. Though he does not at all mention  “acceleration” (which special relativity did not deal with) to achieve this new size, he did open the door to the possibility that size, like distance, is also non-absolute and that the three-dimensional universe as we know it does not have to be static under the laws of relativity. In addition to this, Poincaré indicates that this “change of size” phenomenon would be completely invisible and immeasurable to all observers because of observer invariance.

 

But Einstein had full understanding that a body that was accelerating was also increasing in size.

 

One of the well known properties of acceleration is that:

- accelerating bodies increase in size.

 

 

The late Professor Paul Marmet indicated how observer invariance can play a role in the inflation of matter:

 

Since the moving observer uses his local moving standard units, he might believe that the length does not increase when his own velocity increases. He does not realize that his train is physically longer, but this is not measurable, because his local standard meter has increased in the same proportion. (Paul Marmet, The GPS and the Constant Velocity of Light)

So no new material need be created if material itself is the creation of, and exists because of, an accelerated inflation of all matter in the universe at the particle level.