Stephen Hawking

Stephen Hawking
Born	Stephen William Hawking 8 January 1942
Birthplace	Oxford, England
Died	14 March 2018 Cambridge, England
Nationality	British
Occupation	Theoretical physicist, cosmologist, author
Title	Director of Research, Centre for Theoretical Cosmology
Employer	University of Cambridge
Known for	Hawking radiation, Penrose–Hawking singularity theorems, A Brief History of Time
Education	PhD, University of Cambridge (1966)
Spouse(s)	Jane Wilde (m. 1965; div. 1995), Elaine Mason (m. 1995; div. 2006)
Children	3
Awards	Presidential Medal of Freedom, Fellow of the Royal Society, Lucasian Professor of Mathematics

Stephen William Hawking (8 January 1942 – 14 March 2018) was an English theoretical physicist, cosmologist, and author whose work reshaped the scientific understanding of black holes, the origins of the universe, and the relationship between general relativity and quantum mechanics. Born in Oxford during the Second World War, Hawking spent the majority of his academic career at the University of Cambridge, where he served as the Lucasian Professor of Mathematics from 1979 to 2009 and later as director of research at the Centre for Theoretical Cosmology. His scientific contributions included the theoretical prediction that black holes emit radiation—a phenomenon that came to bear his name—and collaborative work with Roger Penrose on gravitational singularity theorems within the framework of general relativity. Diagnosed with motor neurone disease at the age of 21, Hawking defied medical expectations by living and working for more than five decades after his diagnosis, producing groundbreaking research even as his physical condition progressively deteriorated. He achieved a rare level of public recognition for a scientist, in large part through his bestselling book A Brief History of Time, which remained on the Sunday Times bestseller list for a record-breaking 237 weeks. Hawking was a Fellow of the Royal Society, a lifetime member of the Pontifical Academy of Sciences, and a recipient of the Presidential Medal of Freedom. He died on 14 March 2018 at the age of 76 and was interred at Westminster Abbey.

Early Life

Stephen William Hawking was born on 8 January 1942 in Oxford, England, into a family with a medical background. His birth date fell precisely 300 years after the death of Galileo Galilei, a coincidence Hawking later noted with amusement. His parents were Frank Hawking, a medical researcher who specialised in tropical diseases, and Isobel Hawking (née Walker). The family had moved from London to Oxford during the war, as the city was considered safer from German bombing raids.

Hawking grew up primarily in St Albans, Hertfordshire, where the family relocated after the war. He attended St Albans School, where he was recognised by teachers and peers as intellectually gifted, though not always at the top of his class in terms of grades. From an early age he demonstrated an interest in mathematics and the sciences, and he was known among his schoolmates for his curiosity about the workings of the universe.

Despite his father's wish that he study medicine, Hawking was drawn to mathematics and physics. The young Hawking was influenced by a small group of friends who shared his intellectual interests, and together they built a rudimentary computer from recycled parts. His academic tutor at St Albans, Robert Berman, later recalled that Hawking's abilities were evident even at a young age and supported his application to university.

Education

In 1959, at the age of 17, Hawking entered University College, Oxford, to read natural science with a focus on physics. By his own later admission, he found the work at Oxford unchallenging and estimated that he spent approximately one hour per day on his studies during his time as an undergraduate. Despite this, his natural ability was recognised, and he graduated in 1962 with a first-class Bachelor of Arts degree in physics.

Following his undergraduate studies, Hawking moved to Trinity Hall, Cambridge, for his graduate work in applied mathematics and theoretical physics. He initially wished to study under the cosmologist Fred Hoyle, but was instead assigned to Dennis Sciama, who proved to be a formative influence on his scientific development. Hawking's doctoral thesis, completed in 1966, was titled Properties of Expanding Universes. The thesis applied the mathematics of general relativity to the study of the large-scale structure of the universe and laid the groundwork for his subsequent research on singularities and cosmological models.

Career

Early Research and Singularity Theorems

Hawking's career as a theoretical physicist began during his doctoral studies at Cambridge in the early 1960s. Working within the framework of general relativity, he became interested in the mathematical conditions under which spacetime singularities—points of infinite density—must arise. This line of inquiry led to a productive collaboration with Roger Penrose, then at Birkbeck College, London. Together, Hawking and Penrose developed a series of singularity theorems demonstrating that singularities are a general feature of general relativity under physically reasonable conditions, rather than artefacts of the simplifying assumptions used in earlier models.

The Penrose–Hawking singularity theorems, published between 1965 and 1970, established that the universe, under the conditions described by general relativity, must have originated from a singularity—a conclusion with profound implications for the Big Bang theory. The theorems also applied to the gravitational collapse of massive stars, providing a mathematical underpinning for the formation of black holes. This body of work brought Hawking to the attention of the broader physics community and established him as one of the foremost young researchers in gravitational physics.

During this period, Hawking also worked on the properties of black holes, demonstrating that the surface area of a black hole's event horizon can never decrease—a result that drew a striking analogy to the second law of thermodynamics and contributed to what became known as black hole thermodynamics. This insight would prove pivotal to his most celebrated discovery.

Hawking Radiation

In 1974, Hawking published what is considered his most significant scientific contribution: the theoretical prediction that black holes are not entirely black but instead emit thermal radiation due to quantum mechanical effects near the event horizon. This phenomenon, which came to be known as Hawking radiation, was initially met with scepticism and controversy within the physics community, as it appeared to contradict the then-prevailing understanding that nothing could escape from a black hole.

Hawking's argument drew on quantum field theory in curved spacetime. He showed that the intense gravitational field near a black hole's event horizon causes the spontaneous creation of particle–antiparticle pairs from the quantum vacuum. In certain configurations, one particle falls into the black hole while the other escapes, resulting in a net emission of radiation. Over cosmological timescales, this process would cause a black hole to lose mass and eventually evaporate entirely—a prediction that raised the so-called black hole information paradox, which remains one of the central unsolved problems in theoretical physics.

By the late 1970s, following the publication of further research and the work of other physicists who extended and corroborated Hawking's calculations, Hawking radiation was accepted as a major breakthrough in theoretical physics. The prediction united elements of quantum mechanics, general relativity, and thermodynamics in a way that had not previously been achieved, and it stimulated decades of subsequent research into quantum gravity.

Hawking also introduced the concept of micro black holes—hypothetical black holes of very small mass that might have been created in the extreme conditions of the early universe. If such objects existed, Hawking radiation predicted that they would evaporate rapidly, potentially producing detectable bursts of radiation. The search for evidence of micro black holes became a topic of interest in both astrophysics and particle physics.

Lucasian Professorship and Quantum Cosmology

In 1979, Hawking was appointed to the Lucasian Professorship of Mathematics at the University of Cambridge, a position once held by Isaac Newton and Paul Dirac. He held the post for 30 years, until 2009. The appointment confirmed Hawking's status as one of the leading theoretical physicists in the world.

During the 1980s and 1990s, Hawking turned his attention to quantum cosmology—the application of quantum mechanics to the universe as a whole. Working with James Hartle, he proposed the Hartle–Hawking state, a model of the initial conditions of the universe that dispenses with the need for a boundary or edge to spacetime. In this "no-boundary proposal," the universe has no initial singularity or point of creation in the conventional sense; instead, time behaves like a spatial dimension near the Big Bang, and the universe simply exists without a beginning in the way that the surface of a sphere has no edge. This was the first theory of cosmology to be explained by a union of general relativity and quantum mechanics.

Hawking was also a supporter of the many-worlds interpretation of quantum mechanics, which posits that all possible outcomes of quantum measurements are physically realised in an ever-branching multiverse of parallel realities.

After stepping down from the Lucasian Professorship, Hawking continued as director of research at the Centre for Theoretical Cosmology at Cambridge until his death.

Popular Science Writing

In 1988, Hawking published A Brief History of Time: From the Big Bang to Black Holes, a work of popular science that aimed to make cosmology and theoretical physics accessible to non-specialist readers. The book was a remarkable commercial success, appearing on the Sunday Times bestseller list for 237 weeks—a record at the time. It was translated into dozens of languages and sold millions of copies worldwide, making Hawking one of the most recognisable scientists in the world.

Hawking followed A Brief History of Time with several additional works of popular science. These included Black Holes and Baby Universes and Other Essays (1993), a collection of essays and lectures addressing topics ranging from the nature of time to Hawking's own experiences with disability. He later published The Universe in a Nutshell (2001), A Briefer History of Time (2005, co-authored with Leonard Mlodinow), and The Grand Design (2010, also with Mlodinow).

In addition to his solo and co-authored works, Hawking collaborated with his daughter Lucy Hawking on a series of children's science fiction novels, beginning with George's Secret Key to the Universe (2007), designed to introduce young readers to concepts in physics and cosmology.

Media Appearances and Public Profile

Hawking's public profile extended well beyond his published works. In 1992, filmmaker Errol Morris directed the documentary film A Brief History of Time, which explored both Hawking's scientific ideas and his personal life. Hawking also appeared in numerous television programmes, including a series for the Discovery Channel titled Stephen Hawking's Universe.

He made guest appearances on popular entertainment programmes, including multiple appearances on the animated series The Simpsons and the sitcom The Big Bang Theory, as well as a cameo on Star Trek: The Next Generation in which he played himself in a poker game alongside holographic depictions of Isaac Newton and Albert Einstein. These appearances contributed to his status as a cultural icon and helped bridge the gap between academic science and the general public.

Motor Neurone Disease and Disability

In 1963, at the age of 21, while a doctoral student at Cambridge, Hawking was diagnosed with an early-onset, slow-progressing form of motor neurone disease (amyotrophic lateral sclerosis, or ALS). Doctors initially gave him a life expectancy of approximately two years. The disease progressively weakened his muscles over the following decades, eventually leaving him almost entirely paralysed.

Despite his condition, Hawking continued his research, teaching, and public engagement for more than 50 years after his diagnosis. As his physical abilities declined, he became reliant on a wheelchair and, following a tracheotomy in 1985, lost the ability to speak. He subsequently communicated using a speech-generating device, initially controlling it with a handheld switch and later through the movement of a single cheek muscle, as his other voluntary motor functions deteriorated.

Hawking's ability to continue producing scientific work while living with such severe physical limitations became a subject of public fascination and admiration. He spoke publicly about his condition, noting that his disability had in some respects focused his mind on research by removing the distractions of a more physically active life.

Personal Life

Hawking married Jane Wilde on 14 July 1965, while he was still a doctoral student at Cambridge. The couple had three children, including Lucy Hawking, who later became a journalist and author. The marriage was a central part of Hawking's life during his most productive scientific years, and Jane Hawking served as his primary caregiver for much of their time together. The couple divorced in 1995.

Later in 1995, Hawking married Elaine Mason, one of his nurses. The marriage attracted media attention, and the couple divorced in 2006.

Hawking maintained a public interest in political and social issues. He was vocal in his opposition to the 2003 invasion of Iraq. In his later years, Hawking publicly warned about existential risks facing humanity, including the threats posed by climate change, artificial intelligence, engineered viruses, and the possibility of contact with extraterrestrial civilisations.

Hawking died at his home in Cambridge on 14 March 2018, at the age of 76. His death fell on the date sometimes observed as Pi Day (3/14), and coincided with the 139th anniversary of the birth of Albert Einstein. His ashes were interred at Westminster Abbey on 15 June 2018, between the graves of Isaac Newton and Charles Darwin.

Recognition

Hawking received numerous honours and awards throughout his career. He was elected a Fellow of the Royal Society in 1974, at the age of 32, and remained a Fellow for the rest of his life. He was also a lifetime member of the Pontifical Academy of Sciences.

In 2009, Hawking was awarded the Presidential Medal of Freedom by President Barack Obama, the highest civilian honour in the United States. The medal recognised his contributions to science and his role as a public communicator of physics and cosmology.

Hawking received the Albert Einstein Medal, the Wolf Prize in Physics, the Copley Medal from the Royal Society, and the Fundamental Physics Prize. He was awarded the Julius Edgar Lilienfeld Prize by the American Physical Society.

In 2002, Hawking was ranked number 25 in the BBC's poll of the 100 Greatest Britons, a public vote that placed him alongside historical figures from science, politics, literature, and the arts.

Despite receiving many of the most prestigious awards in physics, Hawking was never awarded the Nobel Prize, as the Nobel Committee generally requires experimental or observational confirmation of theoretical predictions. Hawking radiation has not yet been directly observed, though it is considered theoretically well-established.

Legacy

Hawking's contributions to theoretical physics placed him among the most significant physicists of the twentieth and early twenty-first centuries. His work on singularity theorems, black hole thermodynamics, and quantum cosmology opened new areas of research and influenced generations of physicists. The prediction of Hawking radiation remains one of the key theoretical results linking quantum mechanics and gravity, and the black hole information paradox it raised continues to drive research in string theory, quantum information, and related fields.

As a supervisor at Cambridge, Hawking trained numerous doctoral students who went on to distinguished careers in physics, including Bruce Allen, Raphael Bousso, Bernard Carr, Fay Dowker, Gary Gibbons, Thomas Hertog, Raymond Laflamme, and Don Page, among others.

Beyond his strictly scientific legacy, Hawking's role as a public communicator of science was substantial. A Brief History of Time introduced millions of readers to topics in cosmology and theoretical physics that had previously been accessible only to specialists. His willingness to appear on popular television programmes and to engage with the media helped foster broader public interest in science and demonstrated that complex scientific ideas could be communicated to wide audiences.

Hawking's life with motor neurone disease also had a significant impact on public awareness of disability. His decades-long scientific productivity while living with severe physical impairment challenged assumptions about the limitations imposed by disability and inspired many individuals with similar conditions. His use of assistive technology, particularly his speech-generating device, brought attention to the potential of such technologies to improve the lives of people with disabilities.

His doctoral thesis, Properties of Expanding Universes, was made freely available online by the University of Cambridge Library in 2017 and was downloaded more than two million times in its first week of availability, reflecting the enduring public interest in his work.