Question

PLEASE PROVIDE MORE THAN 5 SENTENCES IN DETAIL FOR EACH QUESTION.

1. What is  Albert Einstein’s achievement? What problem did that solve or whose theory did it fix?

2. What was Albert Einstein’s ultimate dream and why couldn’t he accomplish it?

3 . What are the two scales at which quantum mechanics, and general relativity, respectively, are each working well? Why is general relativity failing at the scales of quantum mechanics?

4. What is the unification theory (aka the “theory of everything”) all about? What theory seems to be a good candidate to solve the problems of unification? What is the problem with that candidate theory?

5. What would be your approach at solving this problem of unification? (The most likely and most honest answers, “I don’t know” and “I don’t care”, are not acceptable. Think outside the box and give your boldest and craziest answer, if you seem out of decent ideas.)

Answer 1

Ans 1- Albert Einstein gave SPECIAL THEORY OF RELATIVITY and GENERAL THEORY OF RELATIVITY (although he got noble prize for PHOTOELECTRIC EFFECT). His theory was a general case of theory of gravitation given by NEWTON. Most of the astronomical phenomenon were not explained by NEWTON's theory. Einstein's theory gave a new concept of visualising gravitational force and solved the puzzle of relative concept of time in different frames and in gravitational field. He compared accelerating frame having effect of gravitational field.

Ans 2- Einstein's ultimate dream was to give THEORY OF EVERYTHING. He wanted to combine quantum mechanics with general theory of relativity. Three forces (electromagnetic, weak and strong) were unified in standard model. But gravitation could not be accomodated.The reason was unavailability of mathematical tools and experimental setup to justify what was already accomplished theoretically. Most of einstein's work were later experimentally demonstrated with CERN accelerator in switzerland and HUBBLE space telescope.But there is no unified theory as such given by einstein.

Ans 3 - Quantum mechanics works at ATOMIC scale( < 10-10 m) and General theory of relativity works at ASTRONOMICAL scale ( in Light years or parsec). Quantum mecanics is not compatible with general theory of relativity due to two basic reasons- First of all time is ABSOLUTE at atomic scale in our calculation but according to general theory of relativity, time is RELATIVE. Secondly, time is not a natural free parameter that comes out itself in quantum mechanics i.e no quantum spacetime concept and no spacetime quantisation. Also gauge theory which explains STANDARD MODEL , becomes non-renormalisable theory with gravitation.

Ans 4- Unified theory explains all the 4 forces( EM ,strong, weak, gravitation) in nature. So that any physical phenomenon from atomic scale to astronomical scale can be explained using this unified theory. There are many contenders for unified theory. Some examples are STRING THEORY, SUPERSYMMETRIC THEORY and GAUGE THEORY. Most famous one is String theory in which all fundamental particles are assumed to be made of strings vibrating with different frequency. Problem with the theory is mathematical complexity, adhoc assumption, lot of dimensions invoked and arbitrary constants. Also the theory can't be tested with today accelerator and technology. It will take more than 100 years to develop accelerator of that much energy scale.