Members of the public have been invited to apply for tickets to attend a celebration of Professor Stephen Hawking's life at a memorial service in Westminster Abbey on June 15, with visitors from the future welcome to apply.
Applicants need to fill in a form online and state their date of birth. The application allows people born more than 20 years into the future to come.
Up to now, over 10,000 people from more than 50 countries have applied for tickets.
Hawking once held a "time traveler party" back in 2009, to see if any would turn up if he posted the invite after the party, but no one turned up at that time.
A legendary figure in the modern history of physics, Hawking, who died on March 14 this year, is known for his work with black holes and relativity.
He broke new ground on the basic laws which govern the universe, including the revelation that black holes have a temperature and produce radiation, now known as Hawking radiation.