What Would Happen if High Light Density Hit Water?

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Directing a high photon density light package, such as the entire output of the sun, onto a volume of water for a millisecond would likely vaporize the water due to the intense energy concentration. The discussion emphasizes that the interaction time of photons with atoms is crucial, with milliseconds being relatively long compared to the rapid interactions at the atomic level, which occur in femtoseconds. While the photoelectric effect may not be significant at this frequency, the sheer energy could still lead to rapid evaporation and potential explosive effects. The conversation also touches on the limitations of time scales in electromagnetic interactions, indicating that shorter timescales could yield more noticeable effects. Overall, the consensus is that a concentrated light source could dramatically alter the state of water in a very short time frame.
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what happens if a high photon density light package was directed to a volume of water for a fraction of a second? what would happen?
i mean what if the whole sun's light is to be shined from the concave lens (pretend the sun only shines on 1 side) i mean, the frequency isn't much higher, so PHOTOelectric effect wouldn really happen... but all those photons onto a volume of water (let's presume all photons makes contact) for a millisecond, would the water evaporate and turn into gas exploding?
is it even possible to energies ATOMS in a small time frame?
 
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what happens if a high photon density light package was directed to a volume of water for a fraction of a second? what would happen?
Same as any light - but more so. Details depend on the type of light.

i mean what if the whole sun's light is to be shined from the concave lens (pretend the sun only shines on 1 side)
Oh that would easily vaporize everything it touches.

is it even possible to energies ATOMS in a small time frame?
The time scale of the electromagnetic dipole interaction is of order 10-23s ... milliseconds is more like 10-3s.
 
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Simon Bridge said:
The time scale of the electromagnetic dipole interaction is of order 10-23s ... milliseconds is more like 10-3s.
There is no such thing. The time scale of the interaction is not a property of electromagnetism, but rather the size of the thing it is interacting with. The oft-quoted 10-23 sec is the time it takes light to travel 1 fermi, and is therefore the minimum time it takes for anything to interact with a nucleon.
 
Thanks for the clarification. Timescale does indeed depend on the thing under consideration.
10-18s to cross an atom for eg. we can also talk about the mean-time to ionize a sample given the flux etc etc etc.
Properly the "size" should be the crossection - which does depend on the interaction.

... but OP was talking about the total output from the Sun here so I figured the nuclear interaction oom figure was appropriate here.

The question before us is whether there is sufficient time for the entire photon flux from the Sun, concentrated on "some water" to "excite the atoms". The point I'm trying to make is that the sort of time thought of as "small" (milliseconds) is actually very large.

We could ask what would constitute a time period so small that there would be no noticeable effect I suppose.
I think OP is under the impression that there is a lower threshold time in which nothing would happen.
 
On a millisecond timescale, you probably would not get much happening.

On shorter timescales though... look up "ultrafast" or "femtosecond" lasers to see a huge, diverse amount of physics on light propagation through solids/fluids.

Claude.
 
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