Stephen Hawking is one of the famous names which our mind thinks of while staring at the cosmos. He was known for his exceptional theories and ideas. He was rarely more than halfway up his class with a clumsy and untidy writing but he had a strong will. His contribution to theoretical physics and astrophysics have definitely revolutionized the way we perceive things about stuff like black holes.
Even with his disabilities, he gave something that no other human could but unfortunately never won the most prestigious Nobel prize in his life.
Stephen Hawking was a theoretical physicist or to be precise, a relativistic physicist. A person who uses Einstein’s elaborate theory of relativity as the basis of his own theories. His major contributions include predicting the beginning of the Universe using Einstein’s theory of relativity which he couldn’t achieve, if he started as a student of Fred Hoyle whom he preferred to have as his teacher, as Hoyle believed in steady-state theory and so would had Hawking if he had got him as his teacher. (Interestingly Fred Hoyle was the person who coined the term big bang!!)
Even his most famous theoretical discovery ‘Hawking Radiation’ and ‘Hawking Temperature’ couldn’t get him the Nobel prize.The reason being that they were theories. Nobel prizes are awarded to those physicists whose theories have been proved using experiments by experimental physicists. Even the most revolutionizing theory in the whole century which came out of a single person’s head couldn’t win the Nobel prize. Einstein never won a Nobel for his General and Special theory of relativity, neither for predicting gravitational waves (which were recently observed and confirmed) rather he won it for the photoelectric effect, not a concept that was equally deserving but was well deserved, the reason being that relativity couldn’t be tested experimentally and had no use at that time but Einstein wasn’t wrong. The gravitational waves were also detected a century later! Even the thing that he considered as the biggest mistake of his life( predicting a force that is stopping Universe from contracting into a singularity) wasn’t really a mistake!
But let us return to Stephen Hawking. His work on Hawking radiation is outstanding. After Einstein published his famous theory of relativity, physicists realized that immense gravitational collapse could lead to a weird hole in the space-time itself, off which nothing could escape once it reaches it’s event horizon. Physicists thought that these black holes could consume everything in the universe and would keep on growing in size until Hawking published his famous paper on Hawking radiation He even gave a rough explanation for the infamous information paradox which wasn’t completely proved. He theoretically predicted that black holes must emit radiations which would one day lead to their complete
According to his work, virtual particles are formed from nothing in the space. Space is actually filled with quantum fields and virtual particles are a result of quantum field fluctuations which occurs basically due to Quantum Uncertainty. This is what we assume to be a virtual particle, which comes out in existence from nowhere with it’s anti-virtual particle and then these two combine and annihilate each other. But these fluctuations gets a bit messier near the extreme curvature of space-time, the black holes. When these fluctuations or virtual particles are formed at the event horizon of the black hole, one of the escapes and the other is sucked in. The particle that escapes, borrows energy from black hole itself and is emitted in the form of a mass-less particle or radiation. The larger the radius of black hole, the larger the De Broglie wavelength of the particle emitted which is why large black holes are cool and small ones are explosively hot. The frequency distribution of this radiation is incredibly similar to the thermal/black body radiation graph!
Hawking actually needed the infamous marriage of relativity and quantum mechanics to achieve these results but he accomplished them without quantum gravity or as popularized, theory of everything. Even after such amazing discoveries he couldn’t achieve one of the greatest achievement of lifetime, the Nobel prize.
The reason being that astronomers or astrophysics never found a confirmatory proof for his theories. First of all, locating black holes is a really huge task in itself because black holes are completely invisible as light never exits a black hole. A theoretical physicist can be considered as a candidate for Nobel prize only when his theory is backed up by observational proofs, which were not there for Hawking. A theory is not considered completely true unless it is tested experimentally.
Many theories like the famous string theory are mathematically correct but unfortunately aren’t experimentally proved and that is the main reason why they aren’t considered for The Nobel prize.
Maybe a century later someday we successfully build an instrument powerful enough to test his theories and prove that they are correct just like LIGO (Laser Interferometer Gravitational-Wave Observatory) detected the gravitational waves in 2015-16. That would be a time when Hawking’s name would be on everyone’s mind again. Till then we can just stare up at the night sky and just hope that we are looking at a black hole!