Is it as garbage as it looks?
No this is most likely a falsehood, there is no mathematics that is presented and the idea appears speculative without mathematical and physical reasoning.
This is what I felt too, altough I am not a physicist (just a freshman).
Is it something like M-Theory (an interesting but unproven theory) or is it a complete nonsense?
I would agree with the latter.
This is complete garbage, even worse than the EM=gravity stuff.
Just consider quarks vs electrons. They have different masses, but the same closed volume (???). It doesn't make any sense.
In fact, I think it would've been enough to stop reading after this
The Spacetime Model was also published on November
30th , 2006, on 31 different web sites. It is also referenced on many
sites like Google and Google Books, Yahoo, DMOZ... More than
100 000 internet Users have read it."
Or maybe just after reading he has a patent on it??
From his website it's clear that his misconception that "volume creates curvature" originates from the popular science illustration of how a rubber membrane (with networks of line on it) bends in the presence of a mass. The problem is that he took this analogy too literally, and invented his own theory about it...
I think the scientists who use inappropriate handwaving analogies in popular science books are the real culprits. I believe every such graph showing some inappropriate analogy should be accompanied by a text, "Warning: this is almost a swindle. Don't take it seriously. If you want to really understand it, study the math behind it."
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