After death, the body becomes hard and becomes soft after chanting Buddha. Why? What is the scientific basis?

This is an inevitable process after death. In general, a corpse will harden within 30 minutes -2 hours after death, become completely stiff within 9 hours-12 hours, soften after 30 hours, and return to its original state after 70 hours.

In forensic medicine, this is a sign to judge the time of death.