Miscellaneous
- Nepal Time, the time zone of UTC +5:45, used in the Federal Democratic Republic of Nepal in the Himalayas
- Nocturnal Penile Tumescence, a nighttime erection of the penis, an established accompaniment of Rapid Eye Movement sleep
- Nuclear Non-Proliferation Treaty, an international treaty, opened for signature on July 1, 1968 to limit the spread of nuclear weapons
- No-Plane Theory, the theory that no airplanes flew into the World Trade Center on September 11, 2001
- NPT ensemble, a name for the isothermal–isobaric ensemble where the number of particles (N), pressure (P), and temperature (T) of the system are in equilibrium
Read more about this topic: NPT