Photons from Nothing

[00:00:05]Hello, I'm Mike McCullik.

[00:00:08]Today I'd like to talk to you about the dynamical casemir effect.

[00:00:13]So the the normal casem effect I've talked about before, but that's caused when you have two parallel metal plates and you put them very close together.

[00:00:25]So everywhere there's a a quantum there are quantum fields, quantum particles, quantum waves and outside the plates any wavelength of these waves can exist. So there are lots of waves outside the two plates but between them only the waves that have nodes on the on the plates can can exist. So fewer fewer waves can exist between the the casemir plates.

[00:00:53]So this means that there are more quantum waves pushing the plates together than there are inside them pushing them apart. So they they tend to move together. And this this has been seen in many experiments.

[00:01:05][clears throat] But in in 1970 Gerald Moore suggested uh the dynamical casm effect which is similar but instead of having two plates you just have one and you waggle it about in empty space.

[00:01:21]Now what this does is that whereas the the twin plates of the castmir effect damp the vacuum between them the the the lone mirror or metal plate if you like as it's being moved around it encounters variations in the quantum fields and the electrons then within the metal or the mirror have to move to cancel it and just like in an antenna you get electromagnetic radiation coming off and the production of photons. So this was predicted by by by Gel Moore and it was first seen in 2011 by by a Swedish team led by by Wilson and they published it in in this paper here and they used a very interesting device called a squid. So this is a superconducting quantum interference device that looks a bit like this. So you have a transmission line, the horizontal line. Then there's a conducting loop with two Josephs and junctions shown here by the the black rectangle, black rectangles. And Joseph's [clears throat] junctions are are very interesting. They're composed of they're like capacitors, but composed of superconducting plates close together as shown here with an insulator between. So they they force electrons to jump across a gap with very high acceleration. So it's it's very interesting that this is similar to the the capacitor tests we and others have been doing.

[00:02:58]Joseph's and junctions are very interesting things.

[00:03:02]So Wilson set up this this system with the loop in the Josephson junctions and then they they varied the magnetic field across the squid so that this this effectively varied the length of the transmission line. It varied the inductions of the the system and the length effectively the length of the transmission line. So this was a way to mimic the fact that you're moving a metal plate very fast and in doing this we're able to effectively move the metal plate uh to about 10 10% speed of light at that that speed where so they did it this way because it's impossible to actually move a real plate that fast and vibrate it that fast because it would it would break it would not be physically possible. So this was a way to do it.

[00:03:58]And then and then they they observed photons coming off just as I said their explanation was that this was creating a sort of aerial system which would emit electromagnetic radiation and they saw photons electromagnetic radiation coming off with a wavelength of about 0.4 4 meters.

[00:04:20]But as I always like to try and do, there's an alternative way to to understand this. The the motion of this this mirror or this effective mirror has a particular acceleration associated with it. They can calculate in this this way.

[00:04:37]So the acceleration of the mirror is two times its velocity times the frequency of it. And the frequency was about 10 gigahertz that they they used and the velocity it's it got up to was about 0.1c 10% speed of light. So if we put these numbers in we get that the acceleration of this mirror is 6 * 10 17 m/s per second.

[00:05:05]And so, okay, could these photons be thought of as being unreal radiation, which would be nice and would bring this in line with Qi? Well, yes, it can because the wavelength of unreal radiation associated with that acceleration is given by lambda u is 2c^ 2 a where a is acceleration and that's 0.3 m which agrees with the 0.4 four meters that they observed.

[00:05:37]So, and I've I've actually emailed Wilson about this and I got a a positive reply. One way to think about this is that this is unradiation coming off.

[00:05:52]And so this is similar in a way to some of the propulsion schemes that quantized inertia may provide. And if we could increase the frequency of this system, we might be able to boost the potential thrusts we might get from such a system.

[00:06:10]Okay. So, I hope you've enjoyed this this short and uh you're you're impressed with the dynamical casm effect was which is in fact a beautiful thing.

[00:06:21]And I look forward to speaking to you next time. Goodbye.