"We chose this song because it talks about hope, peace and promise," said Sonam Bhutia, tourism secretary of Darjeeling and one of the festival organisers.
"The song is so inspiring. It talks about a universe without any boundaries," Bhutia said of the 1971 Lennon track.
"The tribute was a gesture on our part to show that we are with the victim's family in their hour of unimaginable sorrow."
The savage attack on the woman has triggered countrywide protests with calls for better safety and an overhaul of laws governing crimes against women.