Waves, particles and Einstein ! 1

Waves are something that have no mass and move at the maximum speed, mass m = 0. speed c = 1. So whats their momentum? p = m.v = 0? Right?

No. For pure waves; momentum does not come from mass. It comes only from motion.

(pure wave; they do not have mass)

For matter waves, on the other hand, momentum comes in two ways, mass as well as motion.

(impure, now they have mass)

Albert Einstein recognized this fact and derived his relation; $latex E = \sqrt {(pc)^2+(mc^2)^2}$

This relation is called as Einstein’s relativistic equation, also Einstein’s mass-energy relation. But more appropriately mass-energy-momentum relation.

Let us consider E as the hypotenuse, p and m; as base or perpendicular as is your choice.

triangle_copyThen $latex E = \sqrt {(pc)^2+(mc^2)^2}$ is Pythagoras Theorem; when p is momentum and m is mass.

For pure waves such as photon … the quanta of light, m = 0.

Hence the Pythagorean Triangle is now one, where the mass side is arbitrary small. Thus E = p. More…

Sean's publications

A Physicist is a physicist’s way of talking about himself. Reply

In my case therefore you see, 0 publications in 2001. The year I joined my PhD, I was learning more about snow-fall, JC Peney and Bus rides. 2002 I have hardly 1 or 2, that was the year when in the later half I was given the privilege of being able to sign for science papers. The next year I am already acquainted quite a bit, so signing more than 1 paper a month is no irksome involvement. I already know what I am signing it for. 20 papers a year. Then it grows to 60 papers the next year, thats papers a month, my team of 400 was producing where I have a legit share of expert contributions, through weeks of data-collection, analysis and data-mining etc. (There would be papers where I won’t have legit share, .. ) The next year 2005-2006 was my peak, 70 papers, You can check my pictures from 05-06 (on f-b) and see how much I was involved in the literally tons of ways experimentalists contribute 😉 No kidding not everything is visible outside the vacuum pipe, its risky)

Then you can see I am gradually climbing down, but its hard enough to climb down faster because you already have a history. Becoming celebrity is a one way affair, no return. With years my direct contribution goes down but history has that which is yet to come and that shows up as bigger share in contribution. (Just like the electron’s history-of-all-path must contribute towards its momenta for future)
I think thats a good connection, like the electrons the Physicists are lost, they are picking on different things and survive and their history makes it bigger. More…

Is a photon always moving at the speed … Reply

Is a photon always moving at the speed of light?

with the following abstract the article has been moved to it’s blog-space @

“Photons are said to be the quantum (प्र-भागी) that carries the energy … More…