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  What would happen if I fired a "planck laser" straight upwards?

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Suppose I have a pocket sized "plank laser" that fires out one plank energy photon every plank time. It's beam diameter is 1 femtometer, and it is as focussed as possible. This device magically breaks conservation of energy, and having no recoil also breaks conservation of momentum.

(So naive linear optics says beam divergence should be on the order of 1 femtometer over 100 km, but I know this is a situation where nonlinearities are important. )

Lets say I gave a 1 second burst of this, pointing upwards through the earths atmosphere into deep space. What happens.

On one hand, this is outputting 3.5*10^52 watts (so joules because it's a 1 second burst). That's 10^5 suns in mass energy. On the other hand, those are all super hard gamma photons which are unlikely to hit anything rather than just leaving at high speed. And if they do hit anything, that seems like it would just cause one particle of air to leave at high speed.

For reference, if the same amount of energy was shone equally in all directions, and in a frequency that would be absorbed, the energy hitting an earthlike planet around alpha centauri would be slightly lower than that planets gravitational binding energy.

So is this something that no one would notice, a solar system destroyer, or something in between?

asked Jun 20, 2023 in Chat by anonymous [ no revision ]
recategorized Jun 20, 2023 by Arnold Neumaier

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