Final answer:
The statement about general relativity predicting antiparticles is incorrect, as antiparticles are predicted by quantum physics, not general relativity.
Step-by-step explanation:
Of the statements about general relativity provided, the only one which is not true is that general relativity predicts that there are antiparticles. The theory of general relativity primarily describes gravity as the curvature of spacetime, predicts that time slows down near massive bodies (time dilation), explains the bending of light near massive objects, and anticipates the existence of gravitational waves. Antiparticles, on the other hand, are a prediction of quantum physics, particularly quantum field theory. This distinction is crucial because general relativity is a classical theory focusing on gravitational effects in the large-scale structure of spacetime, while the existence and properties of antiparticles are part of the quantum domain, which deals with particle physics and small scales.