Actor Eddie Redmayne is to give a reading at the funeral of renowned theoretical physicist Prof Stephen Hawking.
The Oscar winner will be one of several speakers at the service in Cambridge.
Prof Hawking, who had motor neurone disease, died on 14 March, aged 76, at his home in the city.
His eldest son Robert, former student Prof Fay Dowker, and Astronomer Royal Martin Rees will also deliver addresses to the congregation.
Up to 500 invited family, friends and colleagues have been invited to the private service being held at the university church, Great St Mary’s, from 14:00 BST.
As the funeral cortege arrived at the church, the bells rang out 76 times – once for each year of Prof Hawking’s life.
The hundreds of people gathered outside clapped as the hearse pulled up.
An arrangement of white lilies, to represent the universe, and another of white roses representing the polar star was placed on top of his coffin.
It was carried into the church by six porters from Gonville and Caius College, where Prof Hawking was a fellow for more than 50 years.
The porters, who often assisted him when he visited the college for formal dinners, were asked to be pallbearers by the his family.
Among those inside the church was Eddie Redmayne, who played the role of the professor in the 2014 biographical drama The Theory of Everything.
He is due to read Ecclesiastes 3.1-11, while eulogies will be delivered by Robert Hawking and Prof Dowker.
The service will be officiated by the Reverend Dr Cally Hammond, Dean of Gonville and Caius College, where Prof Hawking was a fellow for more than 50 years.
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The funeral will be followed by a private reception at Trinity College.
Professor Hawking’s ashes will be interred next to the grave of Sir Isaac Newton at Westminster Abbey in June.
A condolence book, which was opened on the morning of Prof Hawking’s death, will be available to members of the public in the porters’ lodge of Gonville and Caius College.
A service of thanksgiving for his life will take place at Westminster Abbey in London on 15 June during which time the professor’s ashes will be interred next to the grave of Sir Isaac Newton who was buried there in 1727, and close to that of Charles Darwin, who was buried in 1882.
The Dean of Westminster, the Very Reverend Dr John Hall, said it was “entirely fitting” the professor’s final resting place should be “near those of distinguished fellow scientists”.