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Relativity - Albert's Masterpiece

A hundred years ago, A certain clerk named Albert Einstein published five papers "which changed the whole of physics". Everybody knows that story. But what are the five papers?    What changes did they make? Here we will discuss one of     those five papers, on Special Relativity.

Special Relativity  stems from Maxwell's theory of Electrodynamics and Modifies the principle of Galilien Relativity - don't worry, you don't have to know electrodynamics to know relativity.

Galilien relativity says that in any moving frames, which are moving at constant velocity (or speed) with respect to each other, the laws of Mechanics (Newton's Laws, for instance) appear the same. No experiments can be made to single out any such frame from any other. Even if you look out the window of a moving train, you can say that the earth is moving, the train is not. But electrodynamics came in the way. 

What it said is that the speed of light has a fixed value- independent of frame. What means you could determine if your frame is moving or at rest by measuring the speed of light- a moving frame would observe a different speed (suppose you are moving at 2 x 10^8 m/s , while light moves at 3 x 10^8 m/s, so it appears to you that it moves at 10^8 m/s ... bingo, you found out your speed!). But this was disproved in the very famous Michelson Morley experiment. So, Maxwell's equations must be wrong... but they were verified by many experiments. Maybe Newton's concepts of absolue time were wrong (Oh! How can that be! Newton was God!) Such an idea could only occur to a radical person- Einstein! 

Since the speed must be the same, time must be different and so must distance, in different frames! Only this, recognised Einstein, could make the all the laws of Physics (not only Mechanics) come out the same in all frames! So, this was relativity, the revolution in physics, all from a single statement - the laws of physics come out the same in differenet frames!

This is the genius of Einstein, and I urge you to read about it by downloading his own book at marxist.org And that also contains Einstein's simple description of his General Theory of Relativity, one of the greatest milestones in physics, nah, History!

Do You Have a Computer !
 

I am reading a book `white dwarfs to black holes-legacy of S Chandrasekhar.'In Chandra's time, there were no electronic computers.. and they used to do extensive numerical calculations using hand held machines. he used to have an assistant who would do all such calculations- mainly numerical integrations- and was called a computer! Chandra had 4-5 computers in his time !

I am reading a book `white dwarfs to black holes- legacy of S
Chandrasekhar'. In Chandra's time, there were no electronic computers.. and they used to do extensive numerical calculations using hand held machines. He used to have an assistant who would do all such calculations- mainly numerical integrations- and was called  a computer! Chandra had 4-5 computers in his time!

Looking back: Einstein never used a computer like the ones we have!

Another thing about Chandra was his lectures were full of mathematical derivations. Rarely he would make a mistake of a factor of two or sign- and when found, he would be delighted to correct it!
I was wondering how someone can be so perfectionist. I thought of this Saying `its fine to make mistakes, but at least make new ones!'. I have started noting the mistakes I do in calculations in solving problems. most are repetitions of same mistakes: not noticing the summing index, forgetting to write a factor while expanding brackets, and many more.
Atleast if we don't make same mistakes, our work should be better.

I remember being told by my Maths teacher, mind works faster than hand! and I recall how our Quantum teacher would compute the second derivatives of functions and substitute in a second order differential equations directly. Those functions of the type: e^(something) * (something).
All these things just need simple observations, and spending a while with the problem, after having solved it, thinking `how I can do this in a better way next time'.

Another thing about Chandra is that he wrote his first paper at the age of 18. That is first year of his graduation perhaps. So also, Josephson, and many other great scientists were absolutely young when they made important discoveries.I wonder why even now I am not close to any new results... and why I haven't done it earlier... why is it that so many project works that we do in graduation, post graduation don't result in a single publication.

I don't wish to blame the present system, but finding flaws in it will help to improve it.
 

1.Project students are never thrown into open research areas, areas never explored before. Because guides themselves may not be confident of helping in those areas. Whereas I have two incidences, just to name few, where abroad students
bravely enter in new areas:
:- One guy entered in his lab, let the paper fall down, and the paper landed after swirls in air, and he told his guide that I want to study the fluid dynamics patterns in this problem. They set up an experiment, and studied the same in two dimensions.
:- Other incidence is that of a research scholar asking `why coffee leaves stains on the boundary, and not a filled circular patch where the coffee drop lands on the cloth?'
:- Third one is that of a set of young astronomers, who patiently observed the asteroids for years, and found that their spin axis were all aligned perpendicular to their plane of orbit...
 
2. Guides don't have much faith in students' capabilities... ohh, what a graduate student can do! let them study the textbooks first. or atmost work out an already done research paper. and then students also feel that research is something done only after 6 years after 12th standard.

In these situations we land up just being repeaters, and not
for-leaders. And having grown in same envioronments, when PhDs and Post docs from here take the students, they also give the same kind of projects and the story continues.

We end up taking the science as the boundary of our knowledge, rather
than a place from where to start our venture.

So, let's break the boundaries!    

Author: Abhay M. Karnataki.Abhay is a student of physics and right now he's completing his phd.