This is a very interesting documentary on DMT. It is a research study where they took volunteers ranging from scientists to doctors and administered them DMT in a hospital setting. The results were all very similar as they all reported travelling to new dimensions and communication with similar entities... Every volunteer believed they travelled outside of the body at light speed to different realms... and they all believe they had died as they lost touch on who they were and believed they were in the afterlife. Even after extensive sessions with psychologists, none of them were able to shake off their belief that their experience was real.
One interesting case was that a volunteer thought he has been gone for decades to hundreds of years when in fact he was out for only 15 minutes.
The conclusion of the study was that based on the findings there was substantial evidence to support that DMT is a portal to other dimensions.