Why does E=MC^2? (answered)

I stumbled across this and thought it was well done and interesting.

I never thought to ask “why” E=MC^2. This article answers that.

It is too long to quote enough to make much sense here without copyright violations so you’ll have to visit the site. It also gets pretty mathematical which for some (including me) makes my eyes bleed.

Nevertheless it is pretty cool. If you are interested in the subject it is worth a read I think.

No one thought this was interesting?

I’m kind of sad about that in a distant, minor way.

Guess my nerdiness is more advanced than I had thought. :wink:

In principle I’d find it interesting, but I don’t think I’d be able to understand it.

The most common way to express the results of this equation are stating how much energy is locked in a paperclip or some other small object. This is pretty abstract though, because in practice one could never convert the entirety of a massive object into energy. That sort of thing mostly only happens with tiny fundamental particles.

One neat thing to keep in mind though is that it goes both ways. You can convert mass into energy, but energy can also turn into mass. An example of this is when you try to separate two quarks. The thing about quarks is that they’re never found alone, they can only be found paired up with other quarks. The forces binding them together are too strong. If you try and pull apart two quarks, the force between them stretches like a spring. That “spring” contains potential energy. If you stretch it enough, the energy materializes into two entirely new quarks to pair up with the first two you were trying to pull apart, leaving you back where you started.

Got it marked for later reading - thanks for the link.

Me neither. Soon’s I saw the rotating vectors, I knew I was doomed.


I do not pretend to understand the math, but just the existence of the math is a stunner.

I had assumed the equivalence was a fundamental property of our corner of the metaverse, arbitrarily ‘assigned’, and had it been some other value grossly incompatible with life (yeah, that anthropic thing again) we would not be around to ponder it.

I read a trivia item that said the amount of mass converted to energy in an atomic explosion is less than a dime.

Would it have been more clear (less intimidating) to just drop the “rotation metaphor” and just state the result (that “x^2 - c^2t^2” is fixed)?
I can never tell if I’ve written something legible.

Great site! Very clearly written. And it makes me want to learn the math…