B How does light have energy to follow infinite paths?

[oknow]

A recent Veritasium video demonstrates via experiment that light from a laser pointer takes every possible.path from source to destination, as promulgated by Richard Feynman. These paths need not be straight lines and thus can wander all of spacetime. That implies light is taking an infinite, or near-infinite, number of paths. How does my little laser pointer have enough energy to generate photons/waves that follow infinite paths?

 

[DaveC426913]

It's very bad analogy, but it might provide a start for thought:

Dip your finger in a swimming pool. That tiny movement is enough to propagate waves to every part of the pool. And ight doesn't lose energy like water waves do (at least not over galactic distances).

 

[PeterDonis]

A recent Veritasium video

Please give a link.

 

[PeterDonis]

These paths need not be straight lines

This is true.

and thus can wander all of spacetime.

This is false. There is always some finite (and usually quite small) region of spacetime in which all of the paths in a particular experiment are confined.

How does my little laser pointer have enough energy to generate photons/waves that follow infinite paths?

Your laser pointer doesn't do that. The paths are not paths of real photons or waves or light rays or anything else.

 

[Dale]

When thinking about these wandering paths and energy you have to realize the constructive and destructive interference involved. Light can take two paths which together carry less energy than either one alone due to interference. Just having more paths in no way implies any extra energy.

 

[BvU]

Perhaps the video "How big is a photon" can shed some light here ...



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[A.T.]

Please give a link.

The key part is linked below. The obvious question relevant to the OPs energy concerns is:

When the grating foil is introduced to create the additional laser reflection by preventing the usual almost complete destructive interference there, does the original laser reflection lose intensity, due to more destructive interference at its location?

Or:

If mirror and foil with the right grating was placed all over the table, would the original distinct reflection disappear, as the laser energy gets more or less evenly reflected all over the mirror?