Free energy wouldn't mean free work. The energy still has to be transformed. In that sense, we already have free energy, since we're utilizing such a tiny fraction of what's available already.
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Free energy would make indefinite length attacks on bitcoin network free
"Free energy" is nonsense. It doesn't actually mean anything.
In what sense?
Energy is a measurement, not a substance. Its the potential for change. The energy itself might not even exist. Energy is defined by the substance carrying it, so cheap energy is an abundance of the substance. Push the cheapness to the extreme end of "free" and what you're really saying is infinite mass or velocity.
And that's fine - even the most conservative estimation of the amount of energy around us puts it in the ballpark of infinity. So in one sense, we already have free energy ; in another, it's nonsense. The energy existing doesn't mean it's working for you. A more correct term is : free work. Reframing it as free work makes it clearer - no magic needed.
There will never be free work, so there will never be free energy.
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