Light waves sonic boom captured

[Pesty]

I think, don't understand it but it cool anyway


Scientists Use 100 Billion FPS Camera to Capture Light’s ‘Sonic Boom’





https://petapixel.com/2017/01/23/scientists-use-10...

[K12beano]

But...but....but.....

No, I don't get that. Why is that a "boom" as opposed to, say, a quantum effect. Or something else....

Confused

[maffski]

It's not really about the light - it's the camera that's new and special.

The light effect was just something that couldn't be imaged before, but was modeled well enough so that the resulting images could be compared to what we thought they should look like.

[XM5ER]

maffski said:

It's not really about the light - it's the camera that's new and special.

The light effect was just something that couldn't be imaged before, but was modeled well enough so that the resulting images could be compared to what we thought they should look like.

Indeed. Its sad that the article misses that. The gif is an actual pulse of light travelling at the speed of light and we can see it in human real time. That's really quite mind blowing.

[SystemParanoia]

I think i need one of these cameras!

Ill use it to catch that yodel delivery driver for once!

[Boring_Chris]

anonymous said:

[redacted]

I thought I had a handle (in a very basic sense) on how it worked so hit 'reply' to try to illustrate my understanding of it. But then thought 'Nah, one more read-through the original wont hurt' and then I realised that I was nowhere near even beginning to understand what's happening here.

[Dr Jekyll]

I don't see how it's remotely analogous to a Mach cone. Things produce a Mach cone when they exceed the speed of sound, light is always travelling at the speed of light. I think they are just illustrating that the camera is fast enough to show the difference between the speed of the laser pulse itself and the lower speed of the light scattered into the plates.

[Yipper]

Light-speed now watchable at human-speed. Very impressive achievement.

[Fugazi]

Dr Jekyll said:

I don't see how it's remotely analogous to a Mach cone. Things produce a Mach cone when they exceed the speed of sound, light is always travelling at the speed of light

I remember reading once that Cherenkov Radiation is the light equivalent of supersonic shock waves. As the speed of light is lower through a dielectric medium, like water and particles can travel faster than the light can propagate through water, it produces a 'shockwave' which manifests itself as faint blue glow.

No idea on what is happening in the video though, probably an artefact of diffusion as you pointed out.