Pulses of light in slow motion

**Box77** · 07-01-2014 12:16 PM

It's a little bit odd news, although I cannot find recent information about this experiment where it was possible to get a slow motion film of pulses of light moving through space.

Here's the video about that project: Visualizing video at the speed of light

My question is: How would it be seen in the following video, if it was projected the pulses of light through a triangular prism in stead of a bottle? Would the pulse disperse its components all at the same time or sort of 'one by one'?

**dutchraptor** · 07-02-2014 12:44 AM

Since the light is a parcel of photons (and assuming I understood your question) I think the dispersion would happen simultaneously

Though I think the light leaving the prism would all leave at a different time. Since blue light disperses more than red, it would have a further path to travel.

Any thoughts?

**Box77** · 07-02-2014 06:52 AM

Originally Posted by dutchraptor

Since the light is a parcel of photons (and assuming I understood your question) I think the dispersion would happen simultaneously

It wouldn't be the same if photons were sent in a row right? Edit: Is it plausible to say that 'photons in a row' would show up like a constant wavelength?

Originally Posted by dutchraptor

Though I think the light leaving the prism would all leave at a different time. Since blue light disperses more than red, it would have a further path to travel.

That's what I was wondering although I am not sure about it. I think the spectrum would gradually appear on the surface where it was projected.

This animation shows a constant beam of light being dispersed by a prism:

I think there shouldn't be the light-gray border of the prism in the first place. I understand the white light is actually formed by its wave components traveling together, and perhaps it would be more illustrative if they are also shown on the side before the beam gets to the prism, perhaps with a white background? Anyway, It looks like basically it depends on the angle of the surface where the spectrum was projected to see it gradually appear. If I use just a constant wavelength of light, it will just be refracted by the prism therefore the previous video wouldn't show more than the pulse changing its direction right?

**Box77** · 07-03-2014 12:15 PM

I knew I should watch the TED talk once more!

Well, there I found a couple of clues to look for (not just 'light in slow motion') and it linked to a couple of videos related to the principle of my question which is about the nature of photons I think:

1. This one here which explains in a little bit more detail the process of the camera:

2. and this one which is basically the same although more artistic:

If I'm not wrong, I see they are using only a wavelength of light for the source of it. I infer it's not the equivalent for white light.

Edit: I was wondering how would it be seen if I use a composite package of different wavelengths together, like magenta for example, and project it through a prism. I think I'd see both pulses overlapping and then splitting inside the prism and so. I could say that two photons can occupy the same place at the same time since apparently they are massless although I can see them behave like particles too.

When a photon hits a reflecting surface, does it bounce as a wave of photons, and so forth? I think that every resulting new wave has a lower amount of energy (Is it the same if I say its intensity goes down?). If a photon doesn't bounce and isn't refracted, it should be that its whole energy is absorbed by the surface it hits. When a photon hits a photoreceptor cell, the cell absorbs the whole energy of the photon and then transfers it to the brain.

Our brains are sort of charging? Vision - Light and Neuronal Activity - YouTube

**Box77** · 07-04-2014 01:22 PM

My granny told me once that I am such a heretic because of I didn't remember the name of a saint... or was it the name of a church which had the name of a saint?? I forgot it again. Anyway, here something related to light and energy: Energy balance of Earth

The surface of the Sun has a temperature of about 5,800 Kelvin (about 5,500 degrees Celsius, or about 10,000 degrees Fahrenheit). At that temperature, most of the energy the Sun radiates is visible and near-infrared light.

If I could just cut those videos to show the sequences I'm interested in without the rhetorical speech because of before I realized that light speed actually has a limit and it can be seen moving into space (with a stroboscopic effect trick), I used to think light was something like:

and then, once I was able to see photons (energy) moving into space... "I saw the light" and I was able to understand a lot of concepts that some people use to follow just because of a book say so.