Quantcast
  • Register
PhysicsOverflow is a next-generation academic platform for physicists and astronomers, including a community peer review system and a postgraduate-level discussion forum analogous to MathOverflow.

Welcome to PhysicsOverflow! PhysicsOverflow is an open platform for community peer review and graduate-level Physics discussion.

Please help promote PhysicsOverflow ads elsewhere if you like it.

News

PO is now at the Physics Department of Bielefeld University!

New printer friendly PO pages!

Migration to Bielefeld University was successful!

Please vote for this year's PhysicsOverflow ads!

Please do help out in categorising submissions. Submit a paper to PhysicsOverflow!

... see more

Tools for paper authors

Submit paper
Claim Paper Authorship

Tools for SE users

Search User
Reclaim SE Account
Request Account Merger
Nativise imported posts
Claim post (deleted users)
Import SE post

Users whose questions have been imported from Physics Stack Exchange, Theoretical Physics Stack Exchange, or any other Stack Exchange site are kindly requested to reclaim their account and not to register as a new user.

Public \(\beta\) tools

Report a bug with a feature
Request a new functionality
404 page design
Send feedback

Attributions

(propose a free ad)

Site Statistics

205 submissions , 163 unreviewed
5,082 questions , 2,232 unanswered
5,354 answers , 22,792 comments
1,470 users with positive rep
820 active unimported users
More ...

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

+ 1 like - 0 dislike
313 views

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

Your answer

Please use answers only to (at least partly) answer questions. To comment, discuss, or ask for clarification, leave a comment instead.
To mask links under text, please type your text, highlight it, and click the "link" button. You can then enter your link URL.
Please consult the FAQ for as to how to format your post.
This is the answer box; if you want to write a comment instead, please use the 'add comment' button.
Live preview (may slow down editor)   Preview
Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
If you are a human please identify the position of the character covered by the symbol $\varnothing$ in the following word:
p$\hbar$y$\varnothing$icsOverflow
Then drag the red bullet below over the corresponding character of our banner. When you drop it there, the bullet changes to green (on slow internet connections after a few seconds).
Please complete the anti-spam verification




user contributions licensed under cc by-sa 3.0 with attribution required

Your rights
...