Renowned physicist Professor Stephen Hawking died early Wednesday at the age of 76, his family said in a statement, adding that the professor died peacefully in his sleep at his home in Cambridge.
"We are deeply saddened that our beloved father passed away today. He was a great scientist and an extraordinary man whose work and legacy will live on for many years," his children Lucy, Robert and Tim said.
"His courage and persistence with his brilliance and humour inspired people across the world. He once said, 'It would not be much of a universe if it wasn't home to the people you love.' We will miss him forever."
The eminent physicist was struck down at the age of 21 with amyotrophic lateral sclerosis, the most common form of motor neuron disease, never permitted the illness which ravaged his body to impair his constant search for answers to the fundamental questions of human existence.
Given only two years to live by his doctors at the time of his diagnosis, Hawking, who died at the age of 76 on Wednesday, became one of the world's longest surviving sufferers of the muscle-wasting disease.
Severely and progressively disabled, and speaking through a computer-operated voice synthesizer, Hawking came "to personify the idea of pure, disembodied intellect," the Times once wrote.
Born into an intellectual family on January 8, 1942, Hawking always knew that he wanted to be a scientist. "I have a simple aim. I want to find out where the universe comes from, how and why it began and how it will end," he said.
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He had never been very well coordinated physically as a child: "I was not good at ball games, and my handwriting was the despair of my teachers." His classmates nicknamed him "Einstein" nonetheless.
In 1959, he won a scholarship to Oxford University, and three years later switched to rival Cambridge to conduct research on cosmology - it was just after his move there that he was diagnosed.
At the age of 32, Hawking was made a Fellow of the Royal Society, Britain's most prestigious academic institution. In 1979, he was appointed Lucasian Professor of Mathematics at Cambridge University - the same post once held by Isaac Newton.
He became one of the world's greatest experts on gravity and black holes - places where matter is compressed to the point where the normal laws of space and time break down.
He linked gravity and quantum theory and made the startling discovery that, under certain conditions, black holes can emit sub-atomic particles.
Until that point, it had been assumed that absolutely nothing, not even light, could escape from a black hole. The particles emitted by an evaporating black hole became known as Hawking Radiation
"Although my discovery explains why black holes have to give off thermal radiation, it came as a complete surprise at the time: at first, I thought I must have made a mistake," Hawking wrote.
A sympathizer with the Palestinian plight, Hawking boycotted a 2013 conference in Israel.The cancellation was "his independent decision to respect the boycott, based upon his knowledge of Palestine, and on the unanimous advice of his own academic contacts there," activist group BRICUP said at the time.
Hawking said that when he wrote "A Brief History of Time" in the late 1980s - the book that became a sensation and has sold more than 10 million copies - he believed that mankind would "one day know the mind of God."
In his 2010 book "The Grand Design," Hawking asserted that there was no need for a creator to explain the existence of the universe.
"I regard the brain as a computer which will stop working when its components fail. There is no heaven or afterlife for broken down computers; that is a fairy story for people afraid of the dark," he said on its publication.
One of few scientists to achieve global celebrity, Hawking made appearances as himself in television series "Star Trek" and "The Big Bang Theory," as well as in cartoon form in "The Simpsons" and "Futurama."
He was played by Eddie Redmayne in the 2014 film about his life "A Theory of Everything."
He also received countless honours, including an OBE (Order of the British Empire) award from Queen Elizabeth II in 1982, but never won the coveted Nobel Prize.
In 1965, and already a sick man, Hawking married his first wife, Jane Wilde, with whom he had three children.
In his autobiography, Hawking, who habitually avoided talking about his private life, revealed how Jane became depressed due to the stress of caring for him and the fear that he was going to die.
With his tacit approval she began an affair with a musician in the late 1980s, while Hawkings fell in love with one of his nurses, Elaine Mason.
After 25 years of marriage the couple split and Hawking married Elaine in 1995. That relationship also ended in divorce after 12 years, though only after a police investigation into accusations that Elaine had physically abused her husband.
Hawking also campaigned tirelessly for the disabled. That, he said, was one of his motives behind his life-long ambition to experience weightlessness on a space flight.
"Space, here I come!" he exclaimed after a roller-coaster flight in G-Force One, a Boeing 727 especially adapted to simulate zero gravity, in April, 2007.
But his next goal, to "go into space" on a sub-orbital flight with Richard Branson's Virgin Galactic venture, was not to be realized.
His health steadily worsened, and for the last few years of his life Hawking was permanently on a ventilator.
Too ill to attend his 70th birthday celebrations at Cambridge University, he still managed to move the distinguished guests to tears when a pre-recorded version of his lecture was read out.
"Be curious. And however difficult life may seem, there is always something you can do," he said. "It matters that you don't give up."