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Re:Camera freezes time at 10 trillion frames per second by izzydata on Friday October 12, 2018 @02:21PM (#18203523)
How many frames per second would you need to film at for a photon of light to be in an identical position on 2 frames?
Re:Camera freezes time at 10 trillion frames per second by cimmanom on Friday October 12, 2018 @02:33PM (#18203608)
A photon needs to actually hit the sensor in order to be recorded, so if we're considering the photon to be a particle (rather than a wave) it would have to be in the same position in order to be in two frames at all.
Re:Camera freezes time at 10 trillion frames per second by emeraldd on Friday October 12, 2018 @02:32PM (#18203607)
For 635nm red laser light, you'd need to be sampling somewhere in the order of 9.4 x 10^14 times a second to get two samples per cycle. Based on roughly 300000000m /635nm x2 but then the question comes down to how many cycles make up a photon and does that question even. Make sense in the first place.
Re:Camera freezes time at 10 trillion frames per second by abhishekjha on Friday October 12, 2018 @10:04PM (#18205970)
>9.4 x 10^14

Can you explain how did you get this number for the red wavelength?

Also can we fundamentally "see" a photon?

Re:Camera freezes time at 10 trillion frames per second by emeraldd on Saturday October 13, 2018 @01:52PM (#18209138)
I was working from the idea of a nyquist or sampling rate needed to "perfectly" reproduce a wave form. I know this works for lower frequencies but I have no idea how well it translates to something like optical frequencies/light. You can find frequency from speed / wavelength: f = v/l or in our case f = c / l since we're dealing with light.

I was using 635nm as the wavelength (basically a red laser). That gives you:

3 x 10^8 / 635 x 10^-7 = 4.7 x 10^14

Which should be about 470 terahertz (4.72 x 10^14) give or take a bit. To sample that "perfectly" you'd need to sample at twice the frequency or about 940 terahertz or (9.4 x 10^14).

As to your second question, I know that there are single photon detectors. Past that, you've got me. I don't know if that can be classified as "seeing" or not. As to size, there's https://briankoberlein.com/2015/04/14/thats-about-the-size-o... but that might or might not make sense.

That's about the limit of what I'm willing/able to say on the subject.

Re:Camera freezes time at 10 trillion frames per second by izzydata on Friday October 12, 2018 @02:39PM (#18203661)
I apologize for my uninformed question.
Re:Camera freezes time at 10 trillion frames per second by emeraldd on Friday October 12, 2018 @03:59PM (#18204279)
No apology needed. When things get that small and you're dealing with light, it's a legitimate question. See: https://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality
Re:Camera freezes time at 10 trillion frames per second by refurb on Friday October 12, 2018 @02:28PM (#18203574)
Speed of light ~300 million km/s.

10 trillion frames per second.

Light would have travelled 3cm on each frame.

Re:Camera freezes time at 10 trillion frames per second by rapnie on Friday October 12, 2018 @02:39PM (#18203651)
If you change the km to m: 299,792,458 metres per second
Re:Camera freezes time at 10 trillion frames per second by max68 on Friday October 12, 2018 @02:30PM (#18203588)
Δd = 1cm = 0.01m v = 3e8 m/s

v*Δd = 3e6 frames/s

For the camera to pick up 1cm of difference between frames, you have to capture 3x10^6 frames per second. You can do the limit for how much you want your delta to be just by multiplying by the speed of light.

Re:Camera freezes time at 10 trillion frames per second by jwalton on Friday October 12, 2018 @02:28PM (#18203570)
Light travels roughly 300 billion m/s, so at 10 trillion fps, light moves about 3cm.
Re:Camera freezes time at 10 trillion frames per second by rapnie on Friday October 12, 2018 @02:35PM (#18203631)
Joking? Wikipedia: 299,792,458 metres per second
Re:Camera freezes time at 10 trillion frames per second by caseymarquis on Sunday October 14, 2018 @09:24AM (#18212769)
Wouldn't it be fantastic if it traveled that fast though! The benefit to computing would be enormous.
Re:Camera freezes time at 10 trillion frames per second by rapnie on Sunday October 14, 2018 @06:10PM (#18215774)
Wonder how the universe would look like, then, through our telescopes.