Stephen Hawking

2.1. Family Background

Stephen William Hawking was born on 8 January 1942 in Oxford, England, to Frank and Isobel Eileen Hawking (née Walker). His mother was born into a family of doctors in Glasgow, Scotland. His paternal great-grandfather, from Yorkshire, had over-extended himself buying farmland and went bankrupt during the Great Depression of British Agriculture in the early 20th century. However, his paternal great-grandmother saved the family from financial ruin by opening a school in their home.

Despite their families' financial constraints, both of Hawking's parents attended the University of Oxford, where Frank studied medicine and Isobel studied Philosophy, Politics and Economics. They met shortly after the outbreak of World War II at a medical research institute, where Isobel worked as a secretary and Frank was a medical researcher specializing in tropical diseases. Due to the bombing of London during The Blitz, Isobel moved to Oxford to give birth safely, leading to Stephen's birth there. Stephen had two younger sisters, Philippa and Mary, and an adopted brother, Edward.

In 1950, when Hawking's father became head of the division of parasitology at the National Institute for Medical Research, the family relocated to St Albans, Hertfordshire. In St Albans, the family was known for their high intelligence and somewhat eccentric nature; meals were often spent with each person silently reading a book. They lived a frugal existence in a large, cluttered, and poorly maintained house, and travelled in a converted London taxicab. During one of his father's frequent absences working in Africa, the rest of the family spent four months in Mallorca visiting his mother's friend Beryl and her husband, the poet Robert Graves. Hawking stated that he "modeled himself on" his father, feeling that scientific research was a natural path. He was drawn to physics because it seemed more fundamental and exact than medicine or biology.

2.2. Schooling

Hawking began his schooling at the Byron House School in Highgate, London. He later attributed his initial difficulty in learning to read to the school's "progressive methods." At the age of eight, after the family moved to St Albans, he attended St Albans High School for Girls for a few months, as younger boys were permitted to attend one of the houses there at the time.

He then attended two private schools: first, Radlett School for a year, and from September 1952, St Albans School, Hertfordshire, having passed the eleven-plus examination a year early. Education was highly valued in his family. Hawking's father wished for him to attend Westminster School, but Stephen fell ill on the day of the scholarship examination. As the family could not afford the fees without a scholarship, he remained at St Albans. This had a positive outcome, as Hawking stayed close to a group of friends with whom he enjoyed board games, making fireworks, building model aeroplanes and boats, and engaging in long discussions about Christianity and extrasensory perception. From 1958 onwards, with the help of their mathematics teacher Dikran Tahta, they even constructed a computer using clock parts, an old telephone switchboard, and other recycled components. In 1959, he built a record player from spare parts, which appealed to his father's Yorkshire frugality.

Despite being known as "Einstein" at school, Hawking was not initially outstanding academically. Over time, he began to demonstrate considerable aptitude for scientific subjects. Inspired by Tahta, he decided to pursue mathematics at university. His father, concerned about limited job prospects for mathematics graduates, advised him to study medicine. However, as it was not possible to study mathematics at his father's alma mater, University College, Oxford, Hawking opted for physics and chemistry. Despite his headmaster's recommendation to defer for a year, Hawking successfully took the scholarship examinations in March 1959 and was awarded a scholarship.

2.3. University and Diagnosis

Hawking commenced his university education at University College, Oxford, in October 1959 at the age of 17. For the initial eighteen months, he felt bored and isolated, finding the academic work "ridiculously easy." His physics tutor, Robert Berman, later remarked on Hawking's innate ability, stating that "It was only necessary for him to know that something could be done, and he could do it without looking to see how other people did it."

A notable shift occurred during his second and third years. According to Berman, Hawking made a greater effort to socialize and integrate, evolving into a popular, lively, and witty member of the college. He developed interests in classical music and science fiction. Part of this transformation stemmed from his decision to join the University College Boat Club, where he served as a cox. The rowing coach observed that Hawking cultivated a daredevil image, steering his crew on risky courses that sometimes resulted in damaged boats.

Hawking estimated that he studied approximately 1,000 hours during his three years at Oxford. These unimpressive study habits made his final examinations challenging. He strategically decided to answer only theoretical physics questions, avoiding those that required factual recall. A first-class degree was a prerequisite for his planned graduate studies in cosmology at the University of Cambridge. Anxious, he slept poorly the night before the examinations, and his result was on the borderline between first- and second-class honours, necessitating an oral examination (viva) with the Oxford examiners.

During the viva, when asked about his future plans, Hawking, concerned about being perceived as a lazy and difficult student, confidently stated, "If you award me a First, I will go to Cambridge. If I receive a Second, I shall stay in Oxford, so I expect you will give me a First." He was, in fact, held in higher regard than he realized; Berman noted that the examiners "were intelligent enough to realise they were talking to someone far cleverer than most of themselves." After receiving a first-class BA degree in physics and completing a trip to Iran with a friend, he began his graduate work at Trinity Hall, Cambridge, in October 1962.

It was during his final year at Oxford that Hawking experienced increasing clumsiness, including a fall on some stairs and difficulties with rowing. These problems worsened, and his speech became slightly slurred. His family noticed the changes when he returned home for Christmas, prompting medical investigations. In 1963, at the age of 21, Hawking received the life-altering diagnosis of an early-onset, slow-progressing form of motor neurone disease (MND), also known as amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease. At the time, doctors gave him a life expectancy of only two years.

2.4. Graduate Studies and Early Research

Hawking's first year as a doctoral student at Cambridge proved difficult. He was initially disappointed to be assigned Dennis William Sciama, one of the founders of modern cosmology, as his supervisor, rather than the renowned astronomer Fred Hoyle, whom he had preferred. He also found his training in mathematics insufficient for the rigorous demands of research in general relativity and cosmology.

Following his diagnosis with motor neurone disease, Hawking fell into a deep depression. Despite his doctors' advice to continue his studies, he initially felt there was little purpose. However, his disease progressed more slowly than doctors had predicted, and an initial diagnosis of only two years to live proved unfounded. With Sciama's encouragement, he gradually returned to his work. Hawking began to develop a reputation for both brilliance and brashness, notably when he publicly challenged the work of Fred Hoyle and his student Jayant Narlikar at a lecture in June 1964. Reflecting on this period, Hawking later stated, "Before I got motor neuron disease, I was bored with life. But the prospect of an early death made me realize life was really worth living."

When Hawking commenced his doctoral studies, the physics community was engaged in a significant debate between the prevailing Big Bang and Steady State theories regarding the creation of the universe. Inspired by Roger Penrose's theorem concerning a spacetime singularity at the center of black holes, Hawking applied similar reasoning to the entire universe. Throughout 1965, he dedicated his thesis to this topic. His PhD thesis, titled "Properties of Expanding Universes," was approved in 1966. This period brought other positive developments: Hawking received a research fellowship at Gonville and Caius College at Cambridge, and his essay "Singularities and the Geometry of Space-Time" shared top honors with one by Penrose, winning that year's prestigious Adams Prize.

3.1. Early Work on Singularities and Black Holes

In his early work, often in collaboration with Roger Penrose, Hawking significantly extended the concepts of singularity theorems that he had initially explored in his doctoral thesis. This research not only confirmed the existence of singularities but also proposed the profound theory that the universe itself might have originated from a singularity. Their joint essay was recognized as the runner-up in the 1968 Gravity Research Foundation competition. In 1970, they published a pivotal proof demonstrating that if the universe adheres to general relativity and aligns with any of the models of physical cosmology developed by Alexander Friedmann, then it must have begun as a singularity. In 1969, Hawking accepted a specially created "Fellowship for Distinction in Science" to remain at Caius College.

In 1970, Hawking postulated what became known as the second law of black hole dynamics, which states that the event horizon of a black hole can never decrease in size. Collaborating with James M. Bardeen and Brandon Carter, he proposed the four laws of black hole mechanics, drawing a compelling analogy with thermodynamics. To Hawking's initial irritation, Jacob Bekenstein, a graduate student of John Archibald Wheeler, went further-and ultimately correctly-to apply thermodynamic concepts literally to black holes.

In the early 1970s, Hawking's work with Carter, Werner Israel, and David C. Robinson provided strong support for Wheeler's no-hair theorem. This theorem posits that a black hole, regardless of the original material from which it is formed, can be completely described by only three properties: its mass, electrical charge, and rotation. His essay titled "Black Holes" earned him the Gravity Research Foundation Award in January 1971. Hawking's first book, The Large Scale Structure of Space-Time, co-authored with George Ellis, was published in 1973.

3.2. Hawking Radiation and Thermodynamics

Beginning in 1973, Stephen Hawking shifted his research focus towards the intricate fields of quantum gravity and quantum mechanics. His work in this area was significantly influenced by a visit to Moscow and subsequent discussions with Yakov Borisovich Zel'dovich and Alexei Starobinsky. Their research suggested that, according to the uncertainty principle, rotating black holes might emit particles. To Hawking's initial annoyance, his meticulously checked calculations yielded findings that contradicted his own second law of black hole dynamics, which stated that black holes could never get smaller. Instead, his new calculations supported Bekenstein's reasoning about black hole entropy.

His groundbreaking results, which Hawking presented starting in 1974, demonstrated that black holes emit radiation, now famously known as Hawking radiation. This radiation, a quantum effect, implies that black holes are not entirely black but slowly lose mass and energy, potentially continuing until they exhaust their energy and evaporate. Initially, the concept of Hawking radiation was controversial within the scientific community. However, by the late 1970s, following the publication of further research and theoretical advancements, this discovery gained widespread acceptance as a significant breakthrough in theoretical physics. In recognition of his pioneering work, Hawking was elected a Fellow of the Royal Society (FRS) in 1974, just a few weeks after the announcement of Hawking radiation. At the time, he was one of the youngest scientists to receive this prestigious fellowship.

In 1974, Hawking was appointed to the Sherman Fairchild Distinguished Visiting Professorship at the California Institute of Technology (Caltech). During his time there, he collaborated with his friend and faculty member, Kip Thorne. Their interaction led to a notable scientific wager regarding whether the X-ray source Cygnus X-1 was indeed a black hole. This wager served as an "insurance policy" for Hawking against the possibility that black holes did not exist. Hawking publicly conceded losing this bet in 1990, marking the first of several such wagers he would make with Thorne and other colleagues throughout his career. Hawking maintained strong ties to Caltech, spending approximately a month there almost every year since his initial visit.

3.3. Cosmology and Quantum Gravity

Hawking returned to Cambridge in 1975, assuming a more academically senior post as a reader in gravitational physics. The mid-to-late 1970s saw a surge in public interest surrounding black holes and the physicists who studied them, leading to Hawking being regularly interviewed for both print and television media. Concurrently, his work garnered increasing academic recognition. In 1975, he was honored with both the Eddington Medal and the Pius XI Gold Medal. The following year, he received the Dannie Heineman Prize, the Maxwell Medal and Prize, and the Hughes Medal. In 1977, he was appointed a professor with a chair in gravitational physics. The subsequent year brought him the Albert Einstein Medal and an honorary doctorate from the University of Oxford.

In 1979, Hawking was elected Lucasian Professor of Mathematics at the University of Cambridge, a position previously held by Isaac Newton and Paul Dirac. His inaugural lecture in this esteemed role was titled "Is the End in Sight for Theoretical Physics?" In it, he proposed N = 8 supergravity as the leading theory capable of resolving many of the outstanding problems theoretical physicists were grappling with. This period also coincided with a health crisis that compelled him, albeit reluctantly, to accept home nursing services. Simultaneously, he began to transition his approach to physics, favoring a more intuitive and speculative style over strict mathematical proofs. He famously told Kip Thorne, "I would rather be right than rigorous." In 1981, he put forth the controversial idea that information in a black hole is irretrievably lost when the black hole evaporates. This information paradox directly challenged a fundamental tenet of quantum mechanics and ignited years of intense debate, including the notable "the Black Hole War" with Leonard Susskind and Gerard 't Hooft.

The theory of cosmological inflation, which posits that the universe underwent an incredibly rapid expansion immediately after the Big Bang before settling into a slower expansion, was initially proposed by Alan Guth and further developed by Andrei Linde. Following a conference in Moscow in October 1981, Hawking and Gary Gibbons organized a three-week Nuffield Workshop in the summer of 1982 at Cambridge University titled "The Very Early Universe," which primarily focused on inflation theory. Hawking also embarked on a new line of quantum-theory research concerning the origin of the universe. In 1981, at a Vatican conference, he presented work suggesting that the universe might possess no boundary-neither a beginning nor an ending.

Hawking subsequently developed this research in collaboration with Jim Hartle. In 1983, they published a model known as the Hartle-Hawking state. This proposal suggested that prior to the Planck epoch, the universe had no boundary in space-time; consequently, before the Big Bang, time itself did not exist, rendering the concept of a "beginning" of the universe meaningless. The initial singularity characteristic of classical Big Bang models was replaced by a region analogous to the North Pole. Just as one cannot travel north of the North Pole because it is simply the point where all north-running lines converge and end, there is no boundary beyond this conceptual "North Pole" of the universe. Initially, the no-boundary proposal predicted a closed universe, which carried implications regarding the existence of God. As Hawking explained, "If the universe has no boundaries but is self-contained... then God would not have had any freedom to choose how the universe began."

Hawking did not, however, rule out the existence of a Creator. In A Brief History of Time, he famously asked, "Is the unified theory so compelling that it brings about its own existence?" and stated, "If we discover a complete theory, it would be the ultimate triumph of human reason-for then we should know the mind of God." In his early work, Hawking often spoke of God in a metaphorical sense. While he suggested in the same book that the existence of God was not necessary to explain the origin of the universe, later discussions with Neil Turok led him to realize that the existence of God was also compatible with an open universe. He articulated this by saying, "All my work has shown is that you don't have to say that the way the Universe began was the personal whim of God. But you still have the question, 'Why does the Universe bother to exist?' If you like, you can define God as the answer to that question."

Further work by Hawking in the area of arrows of time led to the 1985 publication of a paper theorizing that if the no-boundary proposition were correct, then when the universe eventually stopped expanding and collapsed, time would run backwards. However, a paper by Don Page and independent calculations by Raymond Laflamme led Hawking to withdraw this concept.

3.4. Later Research and Theoretical Physics

Hawking continued to receive numerous honors during this period. In 1981, he was awarded the American Franklin Medal, and in the 1982 New Year Honours, he was appointed a Commander of the Order of the British Empire (CBE). These accolades, however, did not significantly alter Hawking's financial situation. Motivated by the need to fund his children's education and cover household expenses, he decided in 1982 to write a popular science book about the universe that would be accessible to the general public. Rather than publishing with an academic press, he signed a contract with Bantam Books, a mass-market publisher, and received a substantial advance for his book. The first draft of this book, which would become A Brief History of Time, was completed in 1984.

By 2003, a growing consensus among physicists suggested that Hawking's earlier stance on the irreversible loss of information in a black hole was incorrect. In a 2004 lecture in Dublin, he publicly conceded his 1997 bet with John Preskill, acknowledging his error. However, he also presented his own, somewhat controversial, solution to the information paradox problem, which involved the possibility that black holes might possess more than one topology. In a 2005 paper on the subject, he argued that the information paradox could be explained by examining all the alternative histories of universes, where information loss in those with black holes would be cancelled out by those without such loss. In January 2014, he famously referred to the alleged loss of information in black holes as his "biggest blunder."

As part of another longstanding scientific dispute, Hawking had emphatically argued, and bet, that the Higgs boson would never be found. The existence of this particle was proposed as part of the Higgs field theory by Peter Higgs in 1964. Hawking and Higgs engaged in a heated and public debate over the matter in 2002 and again in 2008. Higgs criticized Hawking's work, complaining that Hawking's "celebrity status gives him instant credibility that others do not have." The Higgs boson was eventually discovered in July 2012 at CERN, following the construction of the Large Hadron Collider. Hawking quickly conceded that he had lost his bet and stated that Higgs deserved the Nobel Prize in Physics, which he indeed received in 2013.

Hawking's final paper, titled A smooth exit from eternal inflation?, was posthumously published in the Journal of High Energy Physics on 27 April 2018. This work explored new ideas about the origin of the universe. Another of his final research studies, Black Hole Entropy and Soft Hair, published in October 2018, delved into the enduring mystery of what happens to information held by objects once they disappear into a black hole. In October 2018, his last book, Brief Answers to the Big Questions, a popular science book presenting his final comments on the most important questions facing humankind, was published.

3.5. Popular Science Communication

One of the first messages Hawking produced with his newly acquired speech-generating device was a request for his assistant to help him finish writing A Brief History of Time. Peter Guzzardi, his editor at Bantam Books, rigorously pushed him to explain his complex ideas in clear, non-technical language, a process that required numerous revisions and occasionally irritated Hawking. The book was finally published in April 1988 in the US and in June in the UK, becoming an extraordinary success. It quickly rose to the top of bestseller lists in both countries and remained there for months, eventually selling an estimated 9 million copies by 2009 and being translated into many languages.

The media attention surrounding its success was intense, with a Newsweek magazine cover and a television special both describing him as "Master of the Universe." This success brought significant financial rewards but also the challenges of celebrity status. Hawking traveled extensively to promote his work and enjoyed late-night social events. However, his difficulty in refusing invitations and visitors left him with limited time for his research and students. Some colleagues expressed resentment over the attention Hawking received, feeling it was disproportionately due to his disability.

He continued to receive further academic recognition, including five more honorary degrees, the Gold Medal of the Royal Astronomical Society (1985), the Paul Dirac Medal (1987), and, jointly with Penrose, the prestigious Wolf Prize (1988). In the 1989 Birthday Honours, he was appointed a Member of the Order of the Companions of Honour (CH). He reportedly declined a knighthood in the late 1990s, in part due to his objection to the UK's science funding policy.

Hawking continued his prolific writing for a popular audience, publishing The Universe in a Nutshell in 2001. In 2005, he co-authored A Briefer History of Time with Leonard Mlodinow, aiming to update his earlier works and make them even more accessible to a broader readership. In 2006, he released God Created the Integers. Alongside Thomas Hertog at CERN and Jim Hartle, from 2006 onwards, Hawking developed a theory of top-down cosmology. This theory posits that the universe did not originate from a single, unique initial state but rather from a superposition of many different possible histories. Consequently, it suggests that formulating a theory to predict the universe's current configuration from one specific initial state is inappropriate. Top-down cosmology proposes that the present "selects" the past from this superposition of many possible histories, offering a potential resolution to the fine-tuning question.

In 2007, Hawking and his daughter Lucy published George's Secret Key to the Universe, a children's book designed to explain complex theoretical physics in an accessible manner, featuring characters reminiscent of the Hawking family. This book was followed by several sequels, including George's Cosmic Treasure Hunt (2009), George and the Big Bang (2011), George and the Unbreakable Code (2014), and George and the Blue Moon (2016).

4.1. Marriages and Family

Hawking met his future wife, Jane Wilde, at a party in 1962. The following year, Hawking was diagnosed with motor neurone disease. In October 1964, the couple became engaged, fully aware of the potential challenges that lay ahead due to Hawking's shortened life expectancy and escalating physical limitations. Hawking later remarked that the engagement provided him with "something to live for." The couple married on 14 July 1965 in their shared hometown of St Albans.

The couple established their residence in Cambridge, within walking distance of Hawking's workplace, the Department of Applied Mathematics and Theoretical Physics (DAMTP). During their initial years of marriage, Jane commuted to London during the week to complete her degree at Westfield College. They also traveled to the United States several times for conferences and physics-related visits. Jane later began a PhD program through Westfield College in medieval Spanish poetry, which she completed in 1981. The couple had three children: Robert, born in May 1967; Lucy, born in November 1970; and Timothy, born in April 1979.

Hawking rarely discussed his illness and physical challenges, even with Jane, a precedent set during their courtship. His increasing disabilities meant that the significant responsibilities of home and family largely fell upon his wife's shoulders, inadvertently allowing him more time to focus on physics. Upon his appointment in 1974 to a year-long visiting professorship at the California Institute of Technology (Caltech) in Pasadena, California, Jane suggested that a graduate or post-doctoral student live with them to assist with his care. Hawking agreed, and Bernard Carr became the first of many students to fulfill this role, traveling with them to Pasadena. The family generally experienced a happy and stimulating year in Pasadena.

Hawking returned to Cambridge in 1975 to a new home and a new academic position as a reader. Don Page, with whom Hawking had developed a close friendship at Caltech, arrived to serve as the live-in graduate student assistant. With Page's help, and later that of a secretary, Jane's responsibilities were reduced, allowing her to resume work on her doctoral thesis and pursue her new interest in singing. Around December 1977, Jane met organist Jonathan Hellyer Jones while singing in a church choir. Hellyer Jones became close to the Hawking family, and by the mid-1980s, he and Jane had developed romantic feelings for each other. According to Jane, her husband was accepting of the situation, stating "he would not object so long as I continued to love him." Jane and Hellyer Jones were determined not to break up the family, and their relationship remained platonic for a long period.

By the 1980s, Hawking's marriage had been under strain for many years. Jane felt overwhelmed by the intrusion of necessary nurses and assistants into their family life. The impact of Hawking's celebrity status was challenging for both colleagues and family members, and the prospect of living up to a worldwide fairytale image proved daunting for the couple. Furthermore, Hawking's views on religion sharply contrasted with Jane's strong Christian faith, leading to significant tension. After undergoing a tracheotomy in 1985, Hawking required round-the-clock nursing care, necessitating three shifts of nurses daily. In the late 1980s, Hawking grew close to one of his nurses, Elaine Mason, to the dismay of some colleagues, caregivers, and family members, who were disturbed by her strong personality and protectiveness. In February 1990, Hawking informed Jane that he was leaving her for Mason and departed the family home. After his divorce from Jane in 1995, Hawking married Mason in September, declaring, "It's wonderful-I have married the woman I love."

In 1999, Jane Hawking published a memoir, Music to Move the Stars, which detailed her marriage to Hawking and its eventual breakdown. Its revelations caused a sensation in the media, but consistent with his usual practice regarding his personal life, Hawking made no public comment, stating only that he did not read biographies about himself. Following his second marriage, Hawking's family felt excluded and marginalized from his life. For a period of about five years in the early 2000s, his family and staff became increasingly worried that he was being physically abused. Police investigations were conducted, but they were ultimately closed as Hawking refused to make a formal complaint.

In 2006, Hawking and Mason quietly divorced, and Hawking subsequently resumed closer relationships with Jane, his children, and his grandchildren. Reflecting on this happier period, a revised version of Jane's book, re-titled Travelling to Infinity: My Life with Stephen, was published in 2007. This memoir was later adapted into the critically acclaimed film, The Theory of Everything, released in 2014.

4.2. Living with ALS

Stephen Hawking lived with a rare, early-onset, slow-progressing form of motor neurone disease (MND), also known as amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease. This fatal neurodegenerative condition affects the motor neurones in the brain and spinal cord, gradually paralyzing the individual over decades.

Hawking first experienced increasing clumsiness during his final year at Oxford, including a fall on some stairs and difficulties with rowing. These problems worsened, and his speech became slightly slurred. His family noticed the changes when he returned home for Christmas, prompting the initiation of medical investigations. The MND diagnosis came when Hawking was 21, in 1963. At the time, doctors gave him a life expectancy of only two years.

By the late 1960s, Hawking's physical abilities had significantly declined; he began to use crutches and could no longer deliver lectures regularly. As he slowly lost the ability to write, he developed compensatory visual methods, including the remarkable ability to conceptualize equations in terms of geometry. The physicist Werner Israel later compared this achievement to Mozart composing an entire symphony in his head. Hawking was fiercely independent and often unwilling to accept help or make concessions for his disabilities. He preferred to be regarded as "a scientist first, popular science writer second, and, in all the ways that matter, a normal human being with the same desires, drives, dreams, and ambitions as the next person." His first wife, Jane, later noted: "Some people would call it determination, some obstinacy. I've called it both at one time or another." He required much persuasion to accept the use of a wheelchair at the end of the 1960s, but he ultimately became notorious for the wildness of his wheelchair driving. While he was a popular and witty colleague, his illness, coupled with his reputation for brashness, sometimes created distance from others.

When Hawking first began using a wheelchair, he utilized standard motorized models. The earliest surviving example of these chairs, made by BEC Mobility, was sold by Christie's in November 2018 for 296.75 K GBP. Hawking continued to use this type of chair until the early 1990s, when his ability to use his hands to drive a wheelchair deteriorated. From that point, he used a variety of different chairs, including a DragonMobility Dragon elevating powerchair from 2007, a Permobil C350 from 2014, and a Permobil F3 from 2016.

Hawking's speech progressively deteriorated, and by the late 1970s, he could only be understood by his immediate family and closest friends. To communicate with others, someone who knew him well would interpret his speech into intelligible sentences. Prompted by a dispute with the university over who would bear the cost of a ramp needed for him to access his workplace, Hawking and his wife campaigned for improved access and support for individuals with disabilities in Cambridge, including adapted student housing at the university. However, Hawking held ambivalent feelings about his role as a disability rights champion; while he wished to help others, he also sought to detach himself from his illness and its challenges. His perceived lack of engagement in this area sometimes led to criticism.

During a visit to CERN on the border of France and Switzerland in mid-1985, Hawking contracted pneumonia, which, given his condition, was life-threatening. He became so critically ill that Jane was asked if life support should be terminated. She refused, but the consequence was a tracheotomy, which necessitated round-the-clock nursing care and resulted in the complete loss of his remaining speech. The National Health Service was prepared to fund a nursing home, but Jane was determined that he would live at home. The cost of this extensive home care was ultimately funded by an American foundation. Nurses were hired for the three shifts required to provide the continuous support he needed. One of these nurses was Elaine Mason, who would later become Hawking's second wife.

For his communication after the tracheotomy, Hawking initially used his eyebrows to select letters on a spelling card. However, in 1986, he received a computer program called the "Equalizer" from Walter Woltosz, CEO of Words Plus, who had developed an earlier version of the software for his mother-in-law, who also had ALS and had lost her ability to speak and write. Using a method he would employ for the rest of his life, Hawking could now simply press a switch to select phrases, words, or letters from a bank of approximately 2,500-3,000 items that were scanned on a screen. The program was originally run on a desktop computer. Elaine Mason's husband at the time, David, a computer engineer, adapted a small computer and attached it to Hawking's wheelchair.

Freed from the need for an interpreter, Hawking commented that he could "communicate better now than before I lost my voice." The voice he used, which had an TAmerican accent, is no longer produced. Despite the later availability of other voices, Hawking chose to retain this original voice, stating that he preferred it and identified with it. Initially, Hawking activated the switch using his hand and could produce up to 15 words per minute. Lectures were prepared in advance and sent to the speech synthesiser in short sections for delivery.

Hawking gradually lost the use of his hand, and by 2005, he began to control his communication device with movements of his cheek muscles, reducing his typing speed to about one word per minute. With this decline, there was a risk of him developing locked-in syndrome. To address this, Hawking collaborated with Intel Corporation researchers on systems that could translate his brain patterns or facial expressions into switch activations. After several prototypes that did not perform as planned, they settled on an adaptive word predictor developed by the London-based startup SwiftKey. This system, similar to his original technology, was further developed by inputting large amounts of Hawking's papers and other written materials, utilizing predictive software akin to modern smartphone keyboards.

By 2009, he could no longer drive his wheelchair independently. The same team that developed his new typing mechanics also worked on a method to control his chair using chin movements. This proved challenging, as Hawking could not move his neck, and trials showed that while he could indeed drive the chair, the movement was sporadic and jumpy. Near the end of his life, Hawking experienced increased breathing difficulties, often requiring the use of a ventilator, and was regularly hospitalized.

4.3. Disability Advocacy and Social Engagement

Starting in the 1990s, Stephen Hawking embraced his role as a public figure and accepted the mantle of a role model for disabled people. He actively engaged in lecturing and participating in fundraising activities to support disability causes. At the turn of the century, he and eleven other humanitarians signed the Charter for the Third Millennium on Disability, a significant document that called upon governments worldwide to implement policies aimed at preventing disability and safeguarding the rights of disabled individuals. In 1999, Hawking was awarded the Julius Edgar Lilienfeld Prize of the American Physical Society.

Hawking, however, held ambivalent feelings about his role as a disability rights champion. While he genuinely desired to help others and improve accessibility, he also sought to detach himself from his illness and its associated challenges, preferring to be seen primarily as a scientist. This nuanced stance sometimes led to criticism regarding his level of engagement in disability advocacy.

In August 2012, Hawking narrated the "Enlightenment" segment of the 2012 Summer Paralympics opening ceremony in London, a powerful moment that highlighted his inspirational status. In 2013, the biographical documentary film Hawking, which featured Hawking himself, was released, offering further insight into his life and struggles. In September 2013, he publicly expressed support for the legalisation of assisted suicide for the terminally ill, arguing that "we don't let animals suffer." In August 2014, Hawking accepted the Ice Bucket Challenge to promote ALS/MND awareness and raise contributions for research. As he had suffered from pneumonia in 2013, he was advised not to have ice poured over him, but his children volunteered to accept the challenge on his behalf.

In late 2006, Hawking revealed in a BBC interview that one of his greatest unfulfilled desires was to travel to space. Upon hearing this, Richard Branson offered him a free flight into space with Virgin Galactic, which Hawking immediately accepted. Beyond personal ambition, he was motivated by the desire to increase public interest in spaceflight and to demonstrate the potential of people with disabilities. On 26 April 2007, Hawking flew aboard a specially-modified Boeing 727-200 jet operated by Zero-G Corp off the coast of Florida to experience weightlessness. Initial fears that the maneuvers would cause him undue discomfort proved incorrect, and the flight was extended to eight parabolic arcs. It was described as a successful test to determine if he could withstand the g-forces involved in space flight. At the time, Hawking's trip to space was projected to occur as early as 2009, but commercial flights to space did not commence before his death.

5.1. Philosophy and Religion

At Google's Zeitgeist Conference in 2011, Stephen Hawking controversially declared that "philosophy is dead." He believed that philosophers "have not kept up with modern developments in science" and "have not taken science sufficiently seriously," concluding that "Philosophy is no longer relevant to knowledge claims" and "their art is dead." He asserted that scientists "have become the bearers of the torch of discovery in our quest for knowledge" and that philosophical problems can now be answered by science, particularly new scientific theories which "lead us to a new and very different picture of the universe and our place in it." This view garnered both praise and criticism. Despite his scientific focus, he acknowledged the distinct domains of human experience, stating, "Love, faith and morality belong to a different category to physics. You cannot deduce how one should behave from the laws of physics. But one could hope that the logical thought that physics and mathematics involves would guide one also in one's moral behavior."

Hawking did not rule out the existence of a Creator in his early work. In A Brief History of Time, he famously asked, "Is the unified theory so compelling that it brings about its own existence?" and stated, "If we discover a complete theory, it would be the ultimate triumph of human reason-for then we should know the mind of God." In this context, he often spoke of God in a metaphorical sense. While he suggested in the same book that the existence of God was not necessary to explain the origin of the universe, later discussions with Neil Turok led him to realize that the existence of God was also compatible with an open universe. He articulated this by saying, "All my work has shown is that you don't have to say that the way the Universe began was the personal whim of God. But you still have the question, 'Why does the Universe bother to exist?' If you like, you can define God as the answer to that question."

However, Hawking was an outspoken atheist. In an interview published in The Guardian, he regarded "the brain as a computer which will stop working when its components fail," and dismissed the concept of an afterlife as a "fairy story for people afraid of the dark." In 2011, narrating the first episode of the American television series Curiosity on the Discovery Channel, Hawking declared: "We are each free to believe what we want and it is my view that the simplest explanation is there is no God. No one created the universe and no one directs our fate. This leads me to a profound realisation. There is probably no heaven, and no afterlife either. We have this one life to appreciate the grand design of the universe, and for that, I am extremely grateful."

Hawking's association with atheism and freethinking was evident from his university years onwards, when he was a member of Oxford University's humanist group. He was later scheduled to appear as the keynote speaker at a 2017 Humanists UK conference. In an interview with El Mundo, he elaborated on his atheistic stance: "Before we understand science, it is natural to believe that God created the universe. But now science offers a more convincing explanation. What I meant by 'we would know the mind of God' is, we would know everything that God would know, if there were a God, which there isn't. I'm an atheist." He further stated, "If you like, you can call the laws of science 'God', but it wouldn't be a personal God that you would meet and put questions to."

5.2. Future of Humanity

In 2006, Stephen Hawking posed an open question on the Internet: "In a world that is in chaos politically, socially and environmentally, how can the human race sustain another 100 years?" He later clarified that he did not know the answer but asked the question "to get people to think about it, and to be aware of the dangers we now face."

Hawking frequently expressed concerns that life on Earth is at significant risk from various threats, including a sudden nuclear war, a genetically engineered virus, global warming, an asteroid collision, or other unforeseen dangers. He stated, "I regard it as almost inevitable that either a nuclear confrontation or environmental catastrophe will cripple the Earth at some point in the next 1,000 years." He believed that such a planet-wide disaster need not result in human extinction if the human race were to establish colonies on additional planets before the disaster. Consequently, Hawking viewed spaceflight and the colonisation of space as crucial and necessary for the long-term future of humanity.

Hawking also stated that, given the immense vastness of the universe, aliens likely exist, but he warned that contact with them should be avoided. He suggested that aliens might pillage Earth for its resources. In 2010, he famously said, "If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans."

Hawking was a prominent voice warning about the potential dangers of superintelligent artificial intelligence (AI). He stated that "the potential benefits are huge... Success in creating AI would be the biggest event in human history. It might also be the last, unless we learn how to avoid the risks." He feared that "an extremely intelligent future AI will probably develop a drive to survive and acquire more resources as a step toward accomplishing whatever goal it has," and that "The real risk with AI isn't malice but competence. A super-intelligent AI will be extremely good at accomplishing its goals, and if those goals aren't aligned with ours, we're in trouble." He also considered that the enormous wealth generated by machines would need to be redistributed to prevent exacerbated economic inequality.

Hawking was concerned about the future emergence of a race of "superhumans" who would be able to design their own evolution. He also argued that computer viruses in today's world should be considered a new form of life, stating that "maybe it says something about human nature, that the only form of life we have created so far is purely destructive. Talk about creating life in our own image." In July 2015, Hawking helped launch Breakthrough Initiatives, a comprehensive effort to search for extraterrestrial life. He also created Stephen Hawking: Expedition New Earth, a documentary on space colonization, which aired as a 2017 episode of Tomorrow's World. In August 2015, Hawking proposed that not all information is lost when something enters a black hole and that there might be a possibility to retrieve information from a black hole according to his theory.

5.3. Politics and Social Issues

Stephen Hawking was a longstanding supporter of the Labour Party in the United Kingdom. He recorded a tribute for the 2000 Democratic presidential candidate Al Gore, and he controversially called the 2003 invasion of Iraq a "war crime." He consistently campaigned for nuclear disarmament and supported stem cell research. He was also a vocal advocate for universal health care and decisive action to prevent climate change. In August 2014, Hawking was among 200 public figures who signed a letter to The Guardian expressing their hope that Scotland would vote to remain part of the United Kingdom in the September referendum on that issue.

Hawking believed that a United Kingdom withdrawal from the European Union (Brexit) would significantly harm the UK's contribution to science, as modern research necessitates international collaboration and the free movement of people across Europe fosters the spread of ideas. He famously quipped to then-Prime Minister Theresa May, "I deal with tough mathematical questions every day, but please don't ask me to help with Brexit." He expressed disappointment over Brexit and warned against the dangers of envy and isolationism.

Hawking was deeply concerned about healthcare, maintaining that he would not have survived into his 70s without the UK's National Health Service (NHS). He particularly feared privatization, stating, "The more profit is extracted from the system, the more private monopolies grow and the more expensive healthcare becomes. The NHS must be preserved from commercial interests and protected from those who want to privatise it." He openly blamed the Conservatives for cutting funding to the NHS, weakening it through privatization, lowering staff morale by holding back pay, and reducing social care. He accused Jeremy Hunt of cherry picking evidence, which Hawking believed debased science. Hawking further asserted, "There is overwhelming evidence that NHS funding and the numbers of doctors and nurses are inadequate, and it is getting worse." In June 2017, Hawking endorsed the Labour Party in the 2017 UK general election, specifically citing the Conservatives' proposed cuts to the NHS, though he also expressed skepticism about Labour leader Jeremy Corbyn's ability to win a general election.

Hawking feared that Donald Trump's policies on global warming could endanger the planet and make global warming irreversible. He stated, "Climate change is one of the great dangers we face, and it's one we can prevent if we act now. By denying the evidence for climate change, and pulling out of the Paris Agreement, Donald Trump will cause avoidable environmental damage to our beautiful planet, endangering the natural world, for us and our children." Hawking further warned that this could lead Earth "to become like Venus, with a temperature of 482 °F ^{(250 °C)}, and raining sulphuric acid." Hawking was also a supporter of a universal basic income. He was critical of the Israeli government's position on the Israeli-Palestinian conflict, stating that their policy "is likely to lead to disaster."

6.1. Media Appearances

In 1988, Hawking, Arthur C. Clarke, and Carl Sagan were interviewed in God, the Universe and Everything Else, where they discussed topics such as the Big Bang theory, the concept of God, and the possibility of extraterrestrial life.

At the release party for the home video version of A Brief History of Time, Leonard Nimoy, who famously played Spock on Star Trek, learned of Hawking's interest in appearing on the show. Nimoy facilitated the contact, and Hawking subsequently played a holographic simulation of himself in an episode of Star Trek: The Next Generation in 1993. The same year, his synthesizer voice was recorded for the Pink Floyd song "Keep Talking", and in 1999, for an appearance on The Simpsons. Hawking appeared in documentaries such as The Real Stephen Hawking (2001), Stephen Hawking: Profile (2002), and Hawking (2013), as well as the documentary series Stephen Hawking, Master of the Universe (2008). He also guest-starred in Futurama and had a recurring role in The Big Bang Theory.

Hawking famously allowed the use of his copyrighted voice in the biographical 2014 film The Theory of Everything, in which he was portrayed by Eddie Redmayne in an Academy Award-winning role. He was featured at the Monty Python Live (Mostly) show in 2014, where a pre-recorded video showed him singing an extended version of the "Galaxy Song" after humorously running over Brian Cox with his wheelchair.

Hawking utilized his fame to advertise various products, including a wheelchair, National Savings, British Telecom, Specsavers, Egg Banking, and Go Compare. In 2015, he applied to trademark his name.

Broadcast in March 2018, just a week or two before his death, Hawking was the voice of The Book Mark II on The Hitchhiker's Guide to the Galaxy radio series, and he was the guest of Neil deGrasse Tyson on StarTalk. The 2021 animated sitcom The Freak Brothers features a recurring character, Mayor Pimco, who is apparently modeled after Stephen Hawking. On 8 January 2022, Google featured Hawking in a Google Doodle on the occasion of his 80th birthday. On Desert Island Discs, Hawking chose a diverse selection of music, including Francis Poulenc's Gloria, Brahms's Violin Concerto, Beethoven's String Quartet No. 15, Wagner's Die Walküre, Act 1, The Beatles's "Please Please Me", Mozart's Requiem, Puccini's "O Principe, che a lunghe carovane", and Edith Piaf's "Non, je ne regrette rien" ("That just about sums up my life."). For his book, he chose George Eliot's Middlemarch, remarking, "I think someone, maybe it was Virginia Woolf, said it was a book for adults. I'm not sure I'm grownup yet, but I will give it a try."

6.2. Awards and Honours

Stephen Hawking received numerous awards and honours throughout his distinguished career, recognizing his profound contributions to science and his inspirational impact. In 1974, he was elected a Fellow of the Royal Society (FRS), a significant early recognition. His nomination citation highlighted his "major contributions to the field of general relativity," stemming from "a deep understanding of what is relevant to physics and astronomy, and especially from a mastery of wholly new mathematical techniques." It further noted his work with Penrose on singularity theorems, establishing that "all realistic cosmological models must possess singularities," and his proofs on the laws governing black holes, including that "the total surface area of the event horizons must increase." The citation also acknowledged his co-authorship of Space-time in the Large with G. Ellis, and his work on cosmological observations and gravitational wave detectors.

Hawking was also a member of several other prestigious academic bodies, including the American Academy of Arts and Sciences (elected 1984), the American Philosophical Society (elected 1984), and the United States National Academy of Sciences (elected 1992).

In 2015, he received the BBVA Foundation Frontiers of Knowledge Award in Basic Sciences, shared with Viatcheslav Mukhanov, for their discovery that galaxies were formed from quantum fluctuations in the early Universe. At the 2016 Pride of Britain Awards, Hawking was honored with the lifetime achievement award "for his contribution to science and British culture." Upon receiving the award from Prime Minister Theresa May, Hawking humorously requested that she not seek his help with Brexit. In July 2017, Hawking was awarded an Honorary Doctorate from Imperial College London.

In 2017, the Cambridge Union Society, in conjunction with Hawking, established the Professor Stephen Hawking Fellowship. This fellowship is awarded annually to an individual who has made an exceptional contribution to the STEM fields and social discourse, with a particular focus on impacts affecting younger generations. Each fellow delivers a lecture on a topic of their choosing, known as the 'Hawking Lecture'. Hawking himself accepted the inaugural fellowship and delivered the first Hawking Lecture in what would be his last public appearance before his death.

Hawking was a member of the advisory board of the Starmus Festival and played a major role in acknowledging and promoting science communication. The Stephen Hawking Medal for Science Communication is an annual award initiated in 2016 to honor members of the arts community for their contributions that help build awareness of science. Recipients receive a medal bearing a portrait of Hawking by Alexei Leonov, with the reverse side depicting Leonov performing the first spacewalk alongside an image of the "Red Special", the guitar of Queen musician and astrophysicist Brian May, reflecting music as another major component of the Starmus Festival. The Starmus III Festival in 2016 was a tribute to Stephen Hawking, and the book of all Starmus III lectures, "Beyond the Horizon", was also dedicated to him. The first recipients of the medals, personally chosen by Hawking, were composer Hans Zimmer, physicist Jim Al-Khalili, and the science documentary Particle Fever.

Other notable awards and honors received by Hawking include:

• Adams Prize (1966)
• Eddington Medal (1975)
• Pius XI Gold Medal (1975)
• Hughes Medal of the Royal Society (1976)
• Dannie Heineman Prize (1976)
• Maxwell Medal and Prize (1976)
• Albert Einstein Medal (1979)
• Franklin Medal (1981)
• Gold Medal of the Royal Astronomical Society (1985)
• Lifetime Member of the Pontifical Academy of Sciences (1986)
• Paul Dirac Medal (1987)
• Wolf Prize in Physics (jointly with Roger Penrose) (1988)
• Prince of Asturias Awards in Concord (1989)
• Julius Edgar Lilienfeld Prize of the American Physical Society (1999)
• Copley Medal from the Royal Society (2006)
• Fonseca Prize (2008)
• Presidential Medal of Freedom (2009)
• Russian Special Fundamental Physics Prize (2013)

Several buildings and institutions have been named in his honor, including the Stephen W. Hawking Science Museum in San Salvador, El-Salvador, the Stephen Hawking Building in Cambridge, and the Stephen Hawking Centre at the Perimeter Institute in Canada. Appropriately, given Hawking's association with time, he unveiled the mechanical "Chronophage" (or time-eating) Corpus Clock at Corpus Christi College, Cambridge in September 2008. During his career, Hawking supervised 39 successful PhD students. As required by Cambridge University policy, Hawking retired as Lucasian Professor of Mathematics in 2009. Despite suggestions that he might leave the United Kingdom as a protest against public funding cuts to basic scientific research, Hawking continued to work as director of research at the Cambridge University Department of Applied Mathematics and Theoretical Physics.

7.1. Death and Funeral

Stephen Hawking died at his home in Cambridge on 14 March 2018, at the age of 76. His family released a statement confirming that he "died peacefully." Tributes poured in from prominent figures across science, entertainment, politics, and other fields worldwide. The flag at Gonville and Caius College flew at half-mast, and a book of condolences was signed by students and visitors. A tribute to Hawking was also made in the closing speech by IPC President Andrew Parsons at the closing ceremony of the 2018 Winter Paralympics in Pyeongchang, South Korea.

His private funeral took place on 31 March 2018, at Great St Mary's Church, Cambridge. Guests at the funeral included The Theory of Everything actors Eddie Redmayne and Felicity Jones, Queen guitarist and astrophysicist Brian May, and model Lily Cole. Additionally, actor Benedict Cumberbatch, who played Stephen Hawking in the 2004 film Hawking, astronaut Tim Peake, Astronomer Royal Martin Rees, and physicist Kip Thorne provided readings at the service. Although Hawking was an atheist, the funeral proceeded with a traditional Anglican service.

Following the cremation, a service of thanksgiving was held at Westminster Abbey on 15 June 2018. His ashes were subsequently interred in the Abbey's nave, positioned between the graves of Sir Isaac Newton and Charles Darwin, a testament to his monumental scientific stature.



Inscribed on his memorial stone are the words "Here lies what was mortal of Stephen Hawking 1942-2018" and his most famed equation, the Bekenstein-Hawking entropy equation. Hawking had directed, at least fifteen years before his death, that this equation be his epitaph. This equation, which describes the temperature and entropy of a black hole, is given by:
:T = ħc³ / (8πGMk)
where T is black hole temperature, ħ is the reduced Planck constant, c is the speed of light, G is the Newtonian constant of gravitation, M is the mass of the black hole, and k is the Boltzmann constant. This relationship between concepts from the disparate fields of general relativity, quantum mechanics, and thermodynamics implies deep connections between them and may foreshadow their unification. The equation's most fundamental implication is the proportionality between black hole entropy and its event horizon area:
:S_BH = k c³ A / (4 ħG)
where S_BH is the Bekenstein-Hawking entropy and A is the surface area of the black hole. This can be more simply expressed as a proportionality between two dimensionless ratios:
:S_BH / k = (1/4) A / l_P²
where l_P is the Planck length. Jacob Bekenstein had conjectured this proportionality, and Hawking confirmed it, establishing the constant of proportionality at 1/4. Calculations based on string theory, first carried out in 1995, have been found to yield the same result. This relationship is conjectured to be valid not just for black holes, but also (since entropy is proportional to information) as an upper bound on the amount of information that can be contained in any volume of space, which has in turn spawned deeper reflections on the possible nature of reality.

In June 2018, it was announced that Hawking's words, set to music by Greek composer Vangelis, would be beamed into space from a European space agency satellite dish in Spain, with the aim of reaching the nearest black hole, 1A 0620-00. Hawking's final broadcast interview, concerning the detection of gravitational waves resulting from the collision of two neutron stars, occurred in October 2017. His final words to the world appeared posthumously in April 2018, in a Smithsonian TV Channel documentary titled, Leaving Earth: Or How to Colonize a Planet. One of his final research studies, entitled A smooth exit from eternal inflation?, about the origin of the universe, was published in the Journal of High Energy Physics in May 2018. Later, in October 2018, another of his final research studies, entitled Black Hole Entropy and Soft Hair, was published, addressing the "mystery of what happens to the information held by objects once they disappear into a black hole." Also in October 2018, Hawking's last book, Brief Answers to the Big Questions, a popular science book presenting his final comments on the most important questions facing humankind, was published.

On 8 November 2018, an auction of 22 personal possessions of Hawking, including his doctoral thesis (Properties of Expanding Universes, PhD thesis, Cambridge University, 1965) and wheelchair, took place, fetching approximately 1.80 M GBP. Proceeds from the auction sale of the wheelchair went to two charities, the Motor Neurone Disease Association and the Stephen Hawking Foundation, while proceeds from the other items went to his estate. In March 2019, the Royal Mint announced it would issue a commemorative 50p coin, available as a commemorative edition, in honor of Hawking, featuring a black hole design. The same month, Hawking's nurse, Patricia Dowdy, was struck off the nursing register for "failures over his care and financial misconduct." In May 2021, an Acceptance-in-Lieu agreement between HMRC, the Department for Culture, Media and Sport, Cambridge University Library, Science Museum Group, and the Hawking Estate, ensured that around 10,000 pages of Hawking's scientific and other papers would remain in Cambridge, while objects including his wheelchairs, speech synthesizers, and personal memorabilia from his former Cambridge office would be housed at the Science Museum. In February 2022, the "Stephen Hawking at Work" display opened at the Science Museum, London, as the start of a two-year nationwide tour.

7.2. Scientific and Cultural Legacy

Stephen Hawking's scientific legacy is profound, characterized by his groundbreaking work on black holes and the origins of the universe. His collaboration with Roger Penrose on singularity theorems provided fundamental insights into the nature of spacetime. His theoretical prediction of Hawking radiation revolutionized the understanding of black holes, demonstrating their connection to quantum mechanics and thermodynamics. His efforts to unify general relativity and quantum mechanics through concepts like the no-boundary proposal significantly advanced the field of cosmology. His later work on the information paradox and top-down cosmology continued to push the boundaries of theoretical physics, even if some of his specific proposals sparked ongoing debate.

Beyond his direct scientific contributions, Hawking's cultural legacy is equally immense. He became a global icon, symbolizing the triumph of the human spirit and intellect over extreme adversity. His best-selling popular science books, particularly A Brief History of Time, made complex scientific concepts accessible to millions worldwide, inspiring a new generation of scientists and fostering a broader public interest in cosmology and theoretical physics. His numerous media appearances, from television shows to films, further cemented his status as a science communicator and a beloved public figure. Hawking's unwavering determination, sharp wit, and ability to articulate profound ideas despite his severe disability made him an enduring source of inspiration, demonstrating that intellectual pursuit knows no physical bounds. His life served as a powerful testament to human resilience and the boundless potential of the mind.

8.1. Popular Science Books

• A Brief History of Time (1988)
• Black Holes and Baby Universes and Other Essays (1993)
• The Universe in a Nutshell (2001)
• On the Shoulders of Giants (2002)
• God Created the Integers: The Mathematical Breakthroughs That Changed History (2005)
• The Dreams That Stuff Is Made of: The Most Astounding Papers of Quantum Physics and How They Shook the Scientific World (2011)
• My Brief History (2013) - Hawking's memoir.
• Brief Answers to the Big Questions (2018)

8.2. Co-authored Popular Books

• The Nature of Space and Time (with Roger Penrose) (1996)
• The Large, the Small and the Human Mind (with Roger Penrose, Abner Shimony, and Nancy Cartwright) (1997)
• The Future of Spacetime (with Kip Thorne, Igor Novikov, Timothy Ferris, and introduction by Alan Lightman, Richard H. Price) (2002)
• A Briefer History of Time (with Leonard Mlodinow) (2005)
• The Grand Design (with Leonard Mlodinow) (2010)

8.3. Forewords to Other Books

• Black Holes & Time Warps: Einstein's Outrageous Legacy by Kip Thorne, with introduction by Frederick Seitz (1994)
• The Physics of Star Trek by Lawrence Krauss (1995)

8.4. Children's Books

Co-written with his daughter Lucy.

• George's Secret Key to the Universe (2007)
• George's Cosmic Treasure Hunt (2009)
• George and the Big Bang (2011)
• George and the Unbreakable Code (2014)
• George and the Blue Moon (2016)

8.5. Films and Series

• A Brief History of Time (1992)
• Stephen Hawking's Universe (1997)
• Hawking - BBC television film (2004) starring Benedict Cumberbatch
• Horizon: The Hawking Paradox (2005)
• Masters of Science Fiction (2007)
• Stephen Hawking and the Theory of Everything (2007)
• Stephen Hawking: Master of the Universe (2008)
• Into the Universe with Stephen Hawking (2010)
• Brave New World with Stephen Hawking (2011)
• Stephen Hawking's Grand Design (2012)
• The Big Bang Theory (2012, 2014-2015, 2017)
• Stephen Hawking: A Brief History of Mine (2013)
• The Theory of Everything - Feature film (2014) starring Eddie Redmayne
• Genius by Stephen Hawking (2016)

8.6. Selected Academic Works

• "The Singularities of Gravitational Collapse and Cosmology" (with R. Penrose) (1970)
• "Gravitational Radiation from Colliding Black Holes" (1971)
• "Black holes in general relativity" (1972)
• "Black hole explosions?" (1974)
• "The development of irregularities in a single bubble inflationary universe" (1982)
• "Wave function of the Universe" (with J. Hartle) (1983)
• "Information loss in black holes" (2005)
• A smooth exit from eternal inflation? (posthumously, 2018)
• Black Hole Entropy and Soft Hair (posthumously, 2018)