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Given that there are a finite number of photons that exist in the universe, and the maximum speed of a photon is governed by the speed of light, is it possible that enough people observed an object, there would not be enough photons for them all to be able to perceive the entire object and parts of it would seem to disappear?

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    $\begingroup$ Photons can come in and out of existence. They are not finite. $\endgroup$ – Ruben Apr 2 '14 at 23:42
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    $\begingroup$ Why do you suppose that there are a finite number of photons? Are you asking if they could they run out if there were a finite number? $\endgroup$ – George G Apr 2 '14 at 23:42
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    $\begingroup$ Photons are not finite because as Ruben says they can pop in and out. To get a finite number hypothetically, you need to block out their creating mechanism. Is that what you intend? $\endgroup$ – Cheeku Apr 2 '14 at 23:45
  • $\begingroup$ I guess it could be possible, but typically human vision relies on the input of billions of photons or more every second in order to create an image that the brain can interpret, so by the time you're down to people only getting 5 or 10 photons per second, they probably won't be able to see the object (it'd be too dark). $\endgroup$ – DumpsterDoofus Apr 2 '14 at 23:50
  • $\begingroup$ What's the difference between disappear (i.e. I know it's right there on the table, but I can't see it) and be invisible (i.e. when I look at the moon, I know that I'm looking at some human footprints, but I can't make them out)? $\endgroup$ – Beta Apr 2 '14 at 23:56
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Let say we have a candle. There are photons emitted from the candle in all directions, a finite number of photons per unit of time. If an observer is far enough away from the candle, the observer will only occasionally see (detect) a photon from the candle.

So as far as I can understand the question, this is the type of situation referred to. At a far enough distance from a source (star, candle, firefly) a photon might or might not be detected by a given observer during a given time interval. Yes, in this sense, the source could seem to disappear, because there will be intervals of time during which no photon is detected from the source.

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  • $\begingroup$ +1, but maybe you could emphasize, for future searches, that the whole hypothesis " given that there are a finite number of photons in the universe" is absolutely wrong. You have answered correctly the header, but the content should be put right , no conservation of photons. $\endgroup$ – anna v Jun 8 '14 at 4:43
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Yes, but it happens all the time.

If other observers have absorbed all the photons which would otherwise have reached you, then they have blocked your view.

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