Early Life and Education:
Born on January 8, 1942, in Oxford, during World War II. Parents chose Oxford for safety, as the Germans had agreed not to bomb the city. Lived in a Victorian house in Highgate, London, which survived a nearby V-2 rocket strike. Attended Byron House School, a progressive school where he learned to read at the age of eight. His sister Philippa, who was taught by conventional methods, could read by the age of four.

Family and Social Life:
His father worked at the National Institute for Medical Research in Mill Hill, and the family moved to St. Albans. Considered eccentric in St. Albans due to his father’s unconventional behavior. Had a close group of school friends with whom he engaged in discussions and debates on various topics.

Contemplations on the Universe:
Intrigued by the idea of the universe’s origin and whether it required divine intervention. Questioned the red shift of light from distant galaxies as evidence of the expanding universe. Considered alternative explanations for the red shift, such as light becoming tired and more red during its journey.

Oxford Education and Attitude:
Hawking attended Oxford University, where the prevailing attitude discouraged hard work and emphasized natural brilliance or acceptance of limitations. Hawking admits to his lack of effort, working only about an hour a day during his time in Oxford, which he shares with many fellow students.

Illness and Life Perspective:
Hawking’s diagnosis with a life-threatening illness changed his perspective on life, making him realize its worth and the importance of pursuing goals.

Final Exams and Interview:
Hawking’s lack of preparation for his final exams led to a nervous night before the exam, resulting in a borderline performance. During an interview to determine his degree, Hawking expressed his desire to do research and study at Cambridge if he received a first-class degree.

Travel Grant to Iran:
To increase his chances of receiving a travel grant, Hawking proposed traveling to Iran, the furthest destination offered. Hawking journeyed with fellow student John Elder, visiting various historical sites, including Isfahan, Shiraz, Persepolis, and Mashhad. Along the way, Hawking and his travel companion survived the Bounsara earthquake while unaware of its magnitude due to illness and language barriers.

Introduction:
Stephen Hawking’s early journey in Cambridge was marked by both obstacles and achievements. From his time at DAMP to his diagnosis with a debilitating condition, Hawking’s pursuit of knowledge and his resilience in the face of adversity shaped his life.

Challenges Faced:
Hawking initially sought to work with renowned astronomer Fred Hoyle, but instead was assigned to Dennis Sharma due to Hoyle’s lack of availability. Hawking faced limited mathematical preparation from his Oxford education, leading to Sharma’s suggestion to focus on astrophysics. After being diagnosed with a severe medical condition, Hawking experienced depression and uncertainty about his future, including the pursuit of his PhD.

Resilience and Achievements:
Despite the challenges, Hawking remained determined to pursue cosmology, diligently studying old textbooks and attending relativity lectures. He persevered through his PhD research, focusing on the question of the universe’s beginning or a bouncing, cyclic universe. Hawking found solace and motivation in his relationship with Jane, who he met at a party and eventually married. He actively contributed to the scientific community, challenging the steady-state theory and exploring the implications of the background microwave radiation.

Conclusion:
Stephen Hawking’s early career was marked by a combination of challenges and triumphs. His resilience and determination, coupled with his intellectual curiosity, paved the way for his groundbreaking work in cosmology and his remarkable legacy as a renowned physicist.

Black Holes and Singularities:
Roger Penrose’s approach to general relativity showed that dying stars inevitably form singularities where spacetime ends. Hawking applied similar arguments to the universe’s expansion, proving that it had a beginning, contradicting Lifshitz and Kaladnikov’s theories.

Hawking’s Eureka Moment:
In 1970, Hawking realized the area theorem: the event horizon’s surface area always increases with additional matter or radiation entering a black hole. The area theorem and no-hair theorems were confirmed by LIGO’s gravitational wave detections of black hole mergers.

Testing the Area and No-Hair Theorems:
Gravitational waves from black hole mergers can be used to test the Kerr solution and the no-hair theorem by comparing the final black hole’s area and synangular momenta with the initial black holes.

The Golden Age of Black Hole Theory:
Before observational evidence, Hawking and others made significant progress in black hole theory, leading to the publication of “The Large-Scale Structure of Spacetime” with George Ellis in 1973.

Bridging General Relativity and Quantum Theory:
Hawking’s next goal was to combine general relativity with quantum theory, but the singularity problem seemed insurmountable. As a warm-up, he investigated particle and field behavior near black holes, leading to his discovery of Hawking radiation.

Hawking Radiation and Black Hole Entropy:
Hawking’s calculations surprisingly showed that black holes emitted radiation, with the emission rate proportional to the horizon’s area. This led to the famous formula expressing black hole entropy in terms of the horizon’s area and fundamental constants.

The Euclidean Approach and the Resolution of Singularities:
Combining general relativity and quantum theory through the Euclidean approach eliminated singularities and resolved the problem of predictability breaking down. Black holes emit thermal radiation, causing them to lose mass and eventually evaporate completely.

The Information Paradox:
Hawking’s radiation posed a paradox: if it carried away energy and information, how could it preserve the information about the black hole’s initial state? This paradox, unresolved for over 40 years, challenges the compatibility of quantum mechanics and general relativity.

Hawking’s Resolution to the Information Paradox:
Hawking eventually proposed that information is not lost in black holes but is not returned in a useful way, similar to burning an encyclopedia. Hawking’s biggest blunder in science was initially believing that information was destroyed in black holes.

Black Hole Information Theory:
Hawking collaborates with Perry, Strominger, and others on a new theory involving super rotation charges to explain information retrieval from black holes. Information is encoded in an infinite set of super translation charges on the black hole’s horizon.

Inflationary Cosmology:
Hawking’s interest in cosmology resurges due to suggestions of an early universe inflationary expansion period with exponentially increasing size. In 1982, he proposes that quantum effects during inflation could create seeds for structures in our universe, similar to radiation from a black hole horizon. The 1982 Cambridge workshop establishes the foundation for the current understanding of inflation, including density fluctuations leading to galaxy formation.

No Boundary Proposal:
Hawking and Hartle develop the Euclidean approach to cosmology, where the universe’s quantum wave function is expressed as a Feynman sum over imaginary-time histories. They propose the no boundary condition, where the universe has no boundary, avoiding the issue of time’s beginning by treating it as a spatial dimension. The universe spontaneously emerges from nothing, starting smooth with tiny departures predicted by inflation, leading to the observed structures.

Observational Verification:
The irregularities in the observed microwave background align with predictions from inflation combined with the no boundary proposal. Evidence for gravitational waves during rapid expansion is predicted by inflation but yet to be firmly established. Upcoming experiments like the Simons Observatory hold promise for providing strong evidence for this primordial signal.

Precision Cosmology and the Cosmic Microwave Background:
Cosmology becomes a precision science with the WMAP satellite results in 2003. The Planck satellite offers a detailed temperature map of the cosmic microwaves, revealing irregularities that predict the formation of galaxies and stars. Ongoing experiments continue to refine observations of the cosmic microwave background.

Popularizing Science and Public Engagement:
Hawking writes “A Brief History of Time” to explain cosmology and the universe’s governing laws to a wider audience. He advocates for scientists to communicate their work to the public, emphasizing the importance of understanding the universe. Hawking encourages public interest in space exploration for the future of humanity.

Looking Forward:
Planned experiments will map billions of galaxies and enhance our understanding of the universe using supercomputers like Cosmos. Gravitational waves may offer a glimpse into the Big Bang’s core. Hawking reflects on the progress made in understanding the universe and encourages curiosity, perseverance, and looking beyond our immediate surroundings.