Energy = Mass

[GrumpyPom]

In ther famous equation e-mc² we are told that mass and energy are the same thing and that one can be transformed into the other. I understand the sun turns Hydrogen (matter) into heat (energy) but cant think of an example of enegy turning into matter. Are there any?

Thanks in advance

[Buenchico]

From the NASA website:
http://imagine.gsfc.n.../answers/970724a.html

Chris

[jake-the-peg]

This happens in high energy collisions like you get in Colliders such as a CERN or when things like cosmic rays hit things.

When particles collide it's not that you get out the constituents like two cars colliding and you'd get 2 engines, 8 wheels and a load of twisted metal.

What happens is that the energy is converted into matter more energy - more exotic heavier particles.

A bit like colliding two mini's really hard and getting out a Ferrari gearbox, and a Porche engine

In the early days of sub atomic research it seemed that every time they fired up the machinery and banged things together they'd get new particles.

I can't remember who it was (Might have been Fermi) came in one day to hear about a new Pion or Kaon and he said "oh no not another one"

It was Murray Gell-Mann who finally came up with the "standard model" which showed the underlying pattern, a bit like a sub-atomic periodic table.

Genius piece of work

[heathfield]

Examples here...

http://en.wikipedia.o...is_of_precious_metals

[igtretd]

It might be worth adding that because the csquared factor is so large, an enormous amount of energy is produced by converting a tiny amount of matter whereas the reverse, energy into matter, requires enormous amounts of energy to create a tiny amount of matter.

Hence only converting mass into energy has any practical (or lethal!) application.