Since the beginning of the Twentieth century, the notion of classical physics has been described by two revolutionary theories, the general theory of relativity which explains how gravity works and the quantum theory which describes how everything apart from gravity works in the material world, these two theories together formed the two pillars of modern science in the twentieth century. Like many other theoretical physicists. Hawking had his eyes fixed on finding one unifying theory, the theory that could unify both Einstein’s theory of relativity and the quantum theory into one single master theory that described the entire universe. In today’s scientific world, string theory is seen as the best candidate for the theory of everything. Hawking an initial critique of the string theory has helped revive the interest in string theory by showing in a 1973 paper coauthored with his Israeli colleague Jacob Beckenstein that black holes must emit a kind of radiation due to a quantum-mechanical effect, radiation led other scientists to reason that they must have a temperature which meant that they also had entropy, in their 1793 paper, Hawking and Beckenstein worked out the formula for the entropy of a black hole. In 1996 Strominger and Curum Vafa of Harvard, used string theory to count a black hole’s quantum states and used that to work out the entropy of a black hole, their formula matched the formula obtained by Hawking and Beckenstein, thus providing higher hopes for string theory.
Even though Hawking’s research in 1973 and Strominger’s research in 1996 concluded with the same formula for the entropy of a black hole, string theory researchers are not celebrating yet. The theory predicts how particles and forces behave at extremely high energies which are billion times higher than the maximum possible energies producible by the particle colliders at CERN and Fermilab, this technological limitations mean that no experimental physics can be conducted that could produce strings and thus experimentally prove or disprove string theory, this inability to prove string theory experimentally makes many critics argue that string theory should be classified as mathematics rather than physics.
“I don’t think its physics yet.” - Glenn Starkman
“It’s beautiful mathematics, which has a chance of becoming physics, no one has figured out how to make any predictions that can be tested”- Glenn Starkman
Even with the lack of
experimental proof, it is still the preferred over other
theories such as loop quantum gravity and twistor theory which
aim to combine quantum physics and the theory of relativity.