Scientists and disability advocates in Ottawa are mourning the loss of Stephen Hawking, long considered a visionary and one of the greatest physicists of all time.

Hawking died Wednesday at the age of 76 in Cambridge, U.K. The theoretical physicist revolutionized people's understanding of black holes, including the now-widely held understanding that they emit radiation.

"[Hawking] showed us that they actually radiate through mechanisms that nobody had thought about," said David Sinclair, a research professor at Carleton University who met Hawking in the early 2000s while serving as the director of the Sudbury Neutrino Observatory.

Those emissions now bear his name and are called Hawking radiation.

"He just made a huge impact on the field," Sinclair said.

Ben Hansson, a third-year astrophysics student, said he was shocked to hear about the death of a man who'd inspired countless physicists and cosmologists.

Hansson read Hawking's A Brief History of Time in middle school and credited it with fueling his drive to study physics.

"I understood maybe a quarter of it, and I thought to myself, 'Wow, I'd like to understand the whole thing someday,"" he said.

'Singular in what he achieved'

Hawking was known around the world, not only for his brilliance but also for living decades longer than the average person diagnosed with the motor neuron disease ALS.

"He had every barrier that you could think of, and yet he was singular in what he achieved in his discipline in physics and astrophysics. He really was astonishing. There's no one who compares to him," said Larry McCloskey, director of the Paul Menton Centre for Students with Disabilities at Carleton University.

"In a way, we thought that he would go on forever. And in part it's because of the astonishing sense of permanency you get from his mind, where he contemplates the origin and the existence and breadth of the universe."

World-renowned physicist Stephen Hawking shares some insights on life and the universe in an interview with CBC-TV. 13:46

Raised profile of ALS

Tammy Moore, CEO of ALS Canada, said Hawking was both an anomaly and an inspiration for others living with the degenerative disease.

"He was able to contribute in such a meaningful way to the world as a whole, in spite of the disabilities that came as a result of ALS," she said.

Hawking's experience was very different from many other people with ALS, Moore said, because the typical lifespan after diagnosis is two to five years.

She said he brought a visibility to the disease and showed what was possible for someone who has access to assistive and communications devices.

Hawking's death was also noted by some for falling on the birthday of another renowned theoretical physicist, Albert Einstein, and Pi Day, celebrating the mathematical constant equal to 3.14.

Hawking was also known for his sense of humour and became a cultural icon, appearing on TV shows like The Big Bang Theory, The Simpsons and Star Trek: The Next Generation.

His life was also the inspiration for the film The Theory of Everything.

New Stephen Hawking biopic is 'a little too romantic' but worth the Oscar buzz, says CBC's film critic 4:28

Many people also took to social media to express their shock and sadness about his death.

Hawking did so much to normalize AAC and AAC voices. Can anyone name another internationally known individual who used a computer to speak? Probably not! But he made people listen by the value of what he said, and that helps all of us other AAC users to be heard. :) <a href="https://t.co/TOfnkVZIhk">https://t.co/TOfnkVZIhk</a> —@derekthebard

In addition to an amazing mind, he was an amazing example of “it is what it is - next!” He squeezed in 55 years of living fully into the 2 years he was given to live with ALS at age 21. We have no excuses. Live well, love always and laugh out loud every day. RIP Stephen Hawking. —@number1brian

I had the privilege of seeing Stephen Hawking <a href="https://twitter.com/Perimeter?ref_src=twsrc%5Etfw">@Perimeter</a> in 2010. It was pretty sublime to be in the same room with this incredible thinker whose books inspired my young mind and helped to shape my worldview. Still inspired by him today, and sad to see him go. <a href="https://twitter.com/hashtag/RIPStevenHawking?src=hash&ref_src=twsrc%5Etfw">#RIPStevenHawking</a> —@carajmarshall

The first time I read A Brief History of Time was 20 years ago. It changed the way I looked at the world around me, and my own life. RIP Stephen Hawking —@_adunn

"I want to know why the universe exists, why there is something greater than nothing." Thank you, Stephen Hawking, for pushing each and every one of us to be curious and to discover. —@KirstyDuncanMP