Astrophysicist, cosmologist, lecturer, media star, author, parent, grandparent -- Stephen Hawking wears many hats in life. But there's even more to one of the world's most famous cheerleaders of science.
Maybe you've heard of his theories on black hole radiation and the origins of the universe, or perhaps you're a fan of his dry sense of humor or speculation about the existence of aliens and God. With his 1988 book "A Brief History of Time" selling more than 9 million copies worldwide, you may think Hawking's ability to become a household name stems from his talent for piquing the imaginations of the masses [source: Radford]. Either way, Hawking has brought us along for the ride in his intellectual explorations to the edge of the universe and beyond.
Hawking's attitude and value for life arguably give his work a philosophical feel. After surpassing doctors' expectations of living a couple of years, he has thrived for nearly five decades with amyotrophic lateral sclerosis (ALS), a motor neuron disease that eventually restricted him to a wheelchair and limited his ability to speak without the aid of technology.
But Hawking's need to make sense of the universe we occupy is equally engrossing.
When asked about the meaning of life in a 2011 interview with The Guardian newspaper, Hawking replied, "We should seek the greatest value of our action." Despite physical limitations, he says his mind is freer than ever -- a duality some say propelled him to function at the level of genius.
In this article, we'll look at what makes Hawking tick, as well as where his work fits in the larger realm of science. On top of it all, we'll explore his appearance as a larger-than-life scientist in light of his challenges managing an increasing physical disability.
Before we delve into the mechanics of black holes and Hawking's views of the universe, let's visit where his life started: amid World War II in Oxford, England.
Birth of an Icon: Hawking's Boyhood
Stephen Hawking was born in Oxford, England, on Jan. 8, 1942, on the 300-year anniversary of the death of Galileo. The family moved from Oxford to St. Albans, a town north of London, when Hawking was 8 years old. His father's routine research trips to Africa and his mother's left-leaning thinking made for a rather interesting upbringing. The fact that Hawking's parents used a former London taxi as the family car certainly drew attention, too.
Although Hawking's interest in math became apparent to him by his 14th birthday, it wasn't until college that he would delve into physics [source: White & Gribbin]. Hawking has famously admitted that he was a less-than-stellar student during his early years. His father, who excelled in medicine, wanted him to follow in his footsteps while Hawking attended University College, Oxford. But Hawking's interests would lead him elsewhere -- to the edge of the universe, you could say.
While studying physics at University College, he lived the life of most students, partaking in the university's rowing team and parties. Friends and colleagues recall his outgoing sense of humor and popularity during his youth [source: Ferguson].
But things would soon change after receiving his first degree and venturing to Cambridge for his doctorate.
First, Hawking's path crossed with that of Jane Wilde at a campus party in 1963, where the couple hit it off. They married in 1965. Second, the then 21-year-old was diagnosed with amyotrophic lateral sclerosis (ALS), the condition also known as Lou Gehrig's disease that damages nerve cells and negatively affects a person's ability to move. Even more shocking was Hawking's prognosis: At the time, his doctors told him he had roughly two years to live.
Suddenly, Hawking had a new outlook on life. He found a burst of vigor in pursuing his doctorate in cosmology at Cambridge University. This is where his contributions to physics really took root. With time, his work earned him 12 honorary degrees and the Lucasian professorship at Cambridge -- an honor once held by the likes of Isaac Newton and Charles Babbage.
Hawking and his first wife had three children before they divorced in 1991. He later married one of his caregivers, Elaine Mason, in 1995. The couple divorced in 2006, with lingering allegations of Mason abusing Hawking -- a situation he denied and refused to talk about to police [sources: Ferguson; The New York Times].
Friend and biographer Kitty Ferguson said Hawking carefully guards his personal life. Because he needs a voice synthesizer to communicate, Hawking is selective with what he says about certain topics. Concerning his first wife's decision to become romantically involved with another person, he said, "It was fine, as long as she went on loving him [Hawking]" [source: Ferguson].
Although Hawking has chosen to protect some of his personal life, he certainly doesn't skimp on voicing his ideas to the scientific community and media. Next, we'll get to the essence of his theories.
Black Hole Science
To begin to understand Hawking's contributions, we must look at the tiny, subatomic particles that comprise everything in our universe. For instance, particle pairs are constantly appearing and disappearing together. In every pair, there's a particle and an antiparticle with the opposite properties, like a proton and its corresponding antiparticle, the antiproton. Without being interrupted, these particles simultaneously appear, cancel each other out and disappear as fast as they arrived.
But Hawking wondered what would happen to these particles if they were face-to-face with a black hole. In the 1970s, Hawking put forth the idea that a black hole likely sucks in one particle -- usually the antiparticle -- while allowing the other particle to escape. According to Hawking's theory, it's this leftover particle at the entrance of a black hole that ends up being emitted as a type of radiation called Hawking radiation.
He hypothesizes that since the other particle falls into the black hole, it helps reduce the mass of the black hole by that incremental amount. Over time, black holes decrease in mass and collapse, resulting in a huge explosion that spits out matter throughout space. In a sense, Hawking's work suggests there's a lot more going on in black holes and the areas around them.
Since researchers have to measure the presence of black holes indirectly, it's been difficult to confirm or counter Hawking's theory. One group created a miniature black hole of sorts in a lab and observed that Hawking radiation could be real [source: Shiga]. Still, others think the theory can only be confirmed by evidence from a real black hole.
Then followed the information paradox -- the debate surrounding what happened to qualities of matter once inside a black hole.
Hawking wasn't afraid to be bold in drawing conclusions. In 1997, he made a bet with colleague John Preskill, arguing that information is permanently lost once it falls into a black hole [source: Hogan]. But in 2004, Hawking admitted that information isn't lost or channeled into another universe, but rather it seeps back into the existing universe in distorted form.
Hawking publicly admitting defeat confirms his attitude toward science as a field that's constantly adding to and correcting itself. His work on black holes might not seem particularly groundbreaking at first glance, but it spurred conversation that might not have taken place otherwise
What does Hawking think about the origins of the universe? Find out on the next page.
The No-Boundary Proposal
Stephen Hawking's ideas also took him to the edge of the universe and back to where it all started. Along with scientist James Hartle, Hawking put forth an idea of what happened before the big bang.
Because the universe is constantly expanding, scientists have suggested that the origins of the universe can be traced by thinking about the process in reverse. While backtracking, Hawking and Hartle realized the universe becomes smaller until you reach the extremely dense and high-energy ball necessary for the big bang to violently set the beginnings of the universe in place. Yet as you get smaller and smaller, you start seeing the origins of the universe at the subatomic level.
Here's where things get a bit complicated. The duo theorized that once you get to such a tiny, detailed level -- where particles spontaneously pop up and disappear, space becomes separated from time. In essence, time loses the meaning we traditionally assign to it. As a result, it's impossible to measure events before the big bang because time -- as we know it -- doesn't exist.
Hawking and Hartle said the universe doesn't have a boundary, much like the Earth's rounded surface lacks an edge. Hawking likens his no-boundary proposal (aka Hawking-Hartle state) for the universe to traveling southward until you reach the South Pole. When you reach the South Pole, the term "south" loses its meaning. The same idea is applied to time before the big bang -- once you trace back the universe to its beginning, the concept of time (as we define it, at least) becomes obsolete.
Biographer and science writer Kitty Ferguson said the no-boundary proposal is less accepted than Hawking radiation. "To this day there are many people in physics who don't accept it as something in physics that can be used as part of other theories -- you can't use it as a starting off point to go somewhere else," Ferguson said.
In more recent years, Hawking has doubted the possibility of a "theory of everything" existing, an all-encompassing theory of theoretical physics that would explain pretty much everything [source: Sample]. He's also a skeptic on finding the Higgs boson, an elusive particle thought to give subatomic particles mass.
Read on to learn about Hawking's more speculative theories.
God, Aliens -- and Hawking
"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," Hawking famously said in a 2011 interview with The Guardian.
At the root of the physicist's beliefs lies the idea that the universe did not need a creator to begin. This is because he thinks the conditions in which the universe began could have spontaneously happened elsewhere. Some label his thoughts as atheistic, but those close to Hawking say he's never used that term to describe himself [source: Ferguson].
Instead, Hawking views God as the embodiment of the laws of physics.
"It's not a personal God in which you have a personal relationship with, or a God that interferes in life -- in our lives or in the universe in general," said Kitty Ferguson, Hawking's friend and biographer. "He does think his no-boundary proposal wipes out the need for God as a creator."
Hawking's comments about God have usually been communicated directly through media outlets, leading some people to wonder whether he carefully crafts statements to get more publicity [source: Fahy].
The well-known scientist has also become more speculative about the existence of aliens in the universe, too. He thinks it's probable that other life forms exist and compares a possible alien visit to Earth to Columbus' trip to the Americas. Extraterrestrials likely have more advanced technology and the potential need to conquer the planet for power or resources, which would lead humans to potentially be wiped out from war or disease [source: Huessner].
Lastly, we'll examine how Hawking has adapted to some of the challenges of ALS.
Mind Over Body
After Hawking was diagnosed with amyotrophic lateral sclerosis (ALS) at 21 years of age, he was forced to balance the stresses of academic life with physical illness. The disease negatively affects brain and spinal neurons, making patients lose control of voluntary motor function and movement.
During the first few years, his condition worsened rapidly. Soon he relied on a wheelchair. By 1974, Hawking was unable to feed himself. Fortunately, the progression of the disease slowed a bit, eventually becoming more gradual over the years. With time, however, he still began losing the use of his voluntary muscles, hands and certain facial expressions.
Hawking previously used his finger to control a computer and voice synthesizer. But once he lost use of his hands, he started depending on twitching a cheek muscle to communicate. Most computers designed for him rely on running lists of words. Whenever the cursor reaches a word or phrase he wishes to use, Hawking will twitch his cheek muscle to select it. Then he'll go on to the next word until he creates a sentence. In the 1990s, by selecting words with his finger, he could pick 10 to 15 words per minute. But with the difficulty of twitching a cheek muscle, he can select about one word per minute [source: Ferguson].
Because of this, most of Stephen Hawking's speeches and interviews are done in advance to save time.
Despite being too ill to attend his 70th birthday celebration, Hawking has remained incredibly active. In fact, some see his dismissive attitude of his condition as a refusal to let it get in the way of life.
For more information about Stephen Hawking and his work, check out the next page.
More Great Links
- BBC News. "Hawking Takes Zero-Gravity Flight." April 27, 2007. (Jan. 20, 2012) http://news.bbc.co.uk/2/hi/6594821.stm
- Cartwright, John. "Information Paradox Simplified." PhysicsWorld.com. Aug. 15, 2011. (Jan. 26, 2012) http://physicsworld.com/cws/article/news/46848
- "Exploring Stephen Hawking's Unfettered Mind." NPR's Fresh Air. Jan. 3, 2012. (Jan 12, 2012) http://www.npr.org/2012/01/03/144312546/stephen-hawking-exploring-an-unfettered-mind
- Fahy, Declan. "Media Made Hawking Famous." Columbia Journalism Review. Jan. 11, 2012. (Jan. 12, 2012) http://www.cjr.org/the_observatory/media_made_hawking_famous.php?page=all
- Ferguson, Kitty. "Stephen Hawking: An Unfettered Mind." Palgrave MacMillian. New York City. 2012.
- Ferguson, Kitty. "How Stephen Hawking Works." Personal Interview. Jan. 17, 2012.
- Hogan, Jenny. "Hawking Concedes Black Hole Bet." New Scientist. July 21, 2004. (Jan. 20, 2012) http://www.newscientist.com/article/dn6193-hawking-concedes-black-hole-bet.html
- Huessner, Ki Mae. "Stephen Hawking on Religion: 'Science Will Win.'" ABC News. June 7, 2010. (Jan. 20, 2012) http://abcnews.go.com/WN/Technology/stephen-hawking-religion-science-win/story?id=10830164#.Txw8N6XOWHc
- Miller, Laura. "Stephen Hawking: An Unfettered Mind": Portrait of a Genius. Salon.com. Jan. 8, 2012. (Jan. 12, 2012) http://www.salon.com/2012/01/09/stephen_hawking_an_unfettered_mind_portrait_of_a_genius/singleton/
- Radford, Tim. "How God Propelled Stephen Hawking into the Bestsellers Lists." The Guardian. July 30, 2009. (Jan. 20, 2012) http://www.guardian.co.uk/science/2009/jul/30/stephen-hawking-brief-history-time
- Sample, Ian. "Stephen Hawking: There is No Heaven; It's a Fairy Story." The Guardian. May 15, 2011. (Jan. 20. 2012) http://www.guardian.co.uk/science/2011/may/15/stephen-hawking-interview-there-is-no-heaven
- Sample, Ian. "What Has Stephen Hawking Done for Science?" The Guardian. Jan. 8, 2012. (Jan. 12, 2012) http://www.guardian.co.uk/science/2012/jan/08/stephen-hawking-science-greatest-hits?intcmp=239
- Sapsted, David. "Hawking and Second Wife Agree to Divorce." The Telegraph. Oct. 20, 2006. (Jan. 12, 2012) http://www.telegraph.co.uk/news/uknews/1531891/Hawking-and-second-wife-agree-to-divorce.html
- Shiga, David. "Hawking Radiation Glimpsed in Artificial Black Hole." New Scientist. Sept. 28, 2010. (Jan. 26, 2011) http://www.newscientist.com/article/dn19508-hawking-radiation-glimpsed-in-artificial-black-hole.html
- StephenHawking.org.uk. "Brief Biography." (Jan. 12, 2012) http://www.hawking.org.uk/about-stephen.html
- The New York Times. "Stephen Hawking Denies Reports That He is a Victim of Abuse." Jan. 24, 2004. (Jan. 20, 2012) http://www.nytimes.com/2004/01/24/world/stephen-hawking-denies-reports-that-he-is-a-victim-of-abuse.html
- U.S. National Library of Medicine. "Amyotrophic Lateral Sclerosis." PubMed Health. Aug. 27, 2010. (Jan. 12, 2012) http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001708/
- White, Michael & Gribbin, John. "Stephen Hawking: A Life in Science." Joseph Henry Press. Washington D.C. 2002.