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Comment by lmilcin | Hacker News Reader

> In short, if I lost 1% of my electrons, I would not be a person anymore. I would be a bomb. A Coulomb bomb, if you will, with an energy equivalent to that of ten billion (modern) atomic bombs. Which would surely destroy the planet. All by removing just 1 out of every 100 of my electrons.

The most energy you can extract from any type of bomb would be if it was converted to energy at 100% efficiency.

70kg of mass is equivalent of 1,5GT of TNT.

So still a lot of bombs, but more like 1,5 thousand 1MT bombs and not "10 billions" of them.

I am not a physicist, but I think what this shows is physical impossibility of having 1% of your charge removed and your body still considered to be body even for an infinitesimal amount of time. To do that you would have to add so much energy to your body that just the mass equivalent of energy would have to be many times more than your body.

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This is incorrect. Creating a charge gradient in a system increases its mass-energy. In this situation the potential energy is dramatically larger than the rest mass of the precharged person.

Edit in response to your edit: what it shows is that it would take an extraordinary amount of energy to cause the change.

Isn't that what I wrote? That separating the charge would be equivalent to adding potential energy basically adding to mass of your 70kg body so that it no longer is 70kg?

He's saying that you have to include the energy you put into the system to remove 1% of the electrons in your E=mc^2 calculation.

Yes, it takes over 70kg of "mass-energy" (e.g. mass converted to energy in nuclear fission) to remove 1% of all electrons in a person weighing 70 kg. That is not, in itself, contradictory.

Depending on how relativistically inclined you are, this may affect what you consider the weight of the person. But this doesn't really matter for the thought experiment.

> The most energy you can extract from any type of bomb would be if it was converted to energy at 100% efficiency.

Under normal circumstances, a bomb's energy is endogenous. But in the blog's thought-experiment, the energy is assumed to be exogenous. Therefore, your assumption that "the explosion is bounded by the mass of the person" doesn't apply to this scenario. Instead of TNT, imagine a rubberband.

> The most energy you can extract from any type of bomb would be if it was converted to energy at 100% efficiency.

Not true, imagine 2 positrons next to each other, the force these particle subject to accelerate to avoid each other is greater than the mass of those positrons itself.

In other words, if you can get accelerated to 0.9999c, you'll possess far larger energy than your rest mass.

We commonly refer to the energy released if the bomb explodes. If what we cared about was the relativistic mass energy of the matter, we wouldn't need to even refer to bombs. We'd just refer to the mass.

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