I was questioning myself this month how to prove/disprove the general, specific, special Relativity law concerning the relation between gravity and time distortion. Then I saw on the web this question above coming up a couple years ago on this site but could not answer it anymore (discussion was closed with no clear answer). I think that using the new ultracentrifuges (2 millions Gs), it can be done. Putting a solution of Iodine 135 isotope in the centrifuge (half life 6,59 hours) and a reference Iodine 135 sample for the same origin outside the centrifuge and spinning it for one week, there should be a very significant difference. As you can see I am not a Physicist and not following all your discussions, I am a genome scientist working a lot in early years with ultracentrifugation for DNA isolation and now retired and interested in the relation between time and gravity.
The question here is a simple experiment where the decay of Iodine 135 that has been spun for one week at 2 millions Gs is compared to the decay of a reference sample that has been left on the table. My intuition is that there will be a difference between the two samples. It is a simple experiment (may not be at 2 millions Gs) with a simple measurement. Any one interested in doing it?
The possibility of slowing time artificially will have many applications.