Because Heim worked in seclusion, his theories and calculations are difficult to follow and contradict some mainstream theories.

The extended theory by drocher and hauser is also difficult to follow and is believed to be incomplete at best.

Until recently, the theory has not passed any normal form of peer review or has been verified through experimentation.

But the successes of the theory so far suggest that HQT really has something to contribute to mainstream physics.

And if gravitophoton field propulsion is proven and feasible, then it would be far superior to any other device we have available now or in the near future.