Who invented mc squared

Jul 23, , am EDT. Jul 15, , am EDT. Jul 8, , am EDT. Jul 1, , am EDT. Jul 20, , am EDT. Jul 19, , am EDT. Jul 18, , am EDT. Jul 17, , am EDT. Jul 16, , am EDT. Edit Story. Jan 23, , am EST. Ethan Siegel Senior Contributor. Public domain image. Paul Ehrenfest. Follow me on Twitter. Check out my website or some of my other work here. The enormous amount of energy released by the Little Boy nuclear weapon was equivalent to the mass of less than a gram of its radioactive fuel.

You extract energy from matter every time you light a candle though the mechanism there is a chemical reaction, rather than a nuclear one. But the light and heat that comes from a candle is but a sliver of the energy contained within. A single candle might light up a romantic dinner, but the energy equivalent to all of the mass inside would be sufficient to level an entire city.

Though the energy-mass equation might appear simple, there are some special cases that appear to challenge its assumptions. Take the case of photons, for example. These particles, which represent packets of light, have zero mass, but still contain energy. The paradox is resolved with a slightly expanded, lesser-known version of the equation.

This formulation adds in momentum, or p, and also multiplies it by the speed of light. Bring them together, though, and they will annihilate each other into pure energy. Unfortunately, given that we don't know any natural sources of antimatter, the only way to produce it is in particle accelerators and it would take 10 million years to produce a kilogram of it.

Particle accelerators studying fundamental physics are another place where Einstein's equation becomes useful. Special relativity says that the faster something moves, the more massive it becomes. In a particle accelerator, protons are accelerated to almost the speed of light and smashed into each other. The high energy of these collisions allows the formation of new, more massive particles than protons — such as the Higgs boson — that physicists might want to study.

Which particles might be formed and how much mass they have can all be calculated using Einstein's equation. It would be nice to think that Einstein's equation became famous simply because of its fundamental importance in making us understand how different the world really is to how we perceived it a century ago. But its fame is mostly because of its association with one of the most devastating weapons produced by humans — the atomic bomb. The equation appeared in the report, prepared for the US government by physicist Henry DeWolf Smyth in , on the Allied efforts to make an atomic bomb during the Manhattan project.

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