Lucy Hawking held back tears as she heard her father’s robotic voice, almost as if he was speaking from the grave.

Stephen Hawking had recorded the message before his death in March.

It was played during the launch of the cosmologist’s final book, Brief Answers to the Big Questions, in London last month.

“I have found it quite hard to adjust to this idea that he is gone because in so many ways it feels like he is still here,” Lucy Hawking told 7.30 after the event.

“We miss him so much I almost can’t bear to think that Christmas is coming.”

Stephen Hawking and daughter Lucy at the EE British Academy Film Awards in London in February 2015. Photo: FilmMagic

In the recorded message of excerpts from his book, the late Stephen Hawking warned of cultural isolation and pointed to the UK’s exit from the European Union and the leadership of Donald Trump as a threats to education.

“With Brexit and Trump now exerting new forces in relation to immigration and the development of education, we are witnessing the global revolt against experts which includes scientists,” he said.

In the only interview with Australian media after the book launch, his daughter said her father was concerned about fractured public discourse.

“I think one thing that really concerned him is the nature of the challenges that the world faces now are global and we are busy dividing ourselves, are ever more fractured, ever more divisive, ever more angry,” she said.

Growing up with a genius

Growing up with Stephen Hawking was anything but conventional, as he meets Nelson Mandela in 2008. Photo: Getty

Lucy is one of three children, along with brothers Robert and Tim, that Stephen Hawking had with his first wife, Jane Wilde.

She said it didn’t dawn on her that he father was a genius until later in life.

“As a teenager I thought I knew everything and that he really knew nothing,” she said.

“I would tell him that quite regularly, which is kind of embarrassing, really.

“He was Dad and I would say things like, ‘Well, what would you know anyway?’

“And then when I became a grown-up, I had to admit he did actually know quite a lot.”

It wasn’t just his intellect that set Hawking apart, he also lived with motor neurone disease for 50 years.

“I understood that our family was different,” Lucy said.

“It was very unusual in the 1970s to have a disabled parent.

“That was really outstanding because you just didn’t see people with disabilities out and about, and they certainly didn’t engage in life in the way my father did.”

‘Each mind needs a spark to achieve its full potential’

The late theoretical physicist Professor Stephen Hawking is not optimistic about the future. Photo: Getty

In his final audio recording, Hawking speaks of the importance of teachers, recalling how he was slow to learn to read and write before a teacher showed him how to use his energy.

“For each mind to achieve full potential it needs a spark, a spark of inquiry and wonder, often that spark comes from a teacher,” Hawking said.

Stephen Hawking’s final book is launched at the Science Museum in London on October 15. Photo: AFP/Getty

Lucy Hawking said he father was a teacher to all of his children but she never felt a pressure to live up to his genius.

“It took me a while to come to terms with the fact that I would never do anything as far-reaching as my father had and I’m OK with that,” she said.

“I’m a very proud advocate for his ideas.”

In the book, Hawking declares there to be no God or afterlife, and that it is time to explore other solar systems because, “Spreading out may be the only thing that saves us from ourselves”.

He predicts computers will overtake humans in intelligence at some point in the next 100 years.

He also writes about climate change, time travel and the future.

“The Earth is under threat from so many areas that it is difficult for me to be positive,” he said.

“The threats are too big and too numerous.”

–ABC