3 ms·
It is a really good question :-). I came across his work because I noodle occasionally on a thread of questions that started with "is there a maximum RF freque
by ChuckMcM 6y ago
It is a really good question :-).
I came across his work because I noodle occasionally on a thread of questions that started with "is there a maximum RF frequency?" and the implications that leads to.
My hypothesis is that there must be such a limit, given that EM waves propagate at the speed of light, thus their wavelength is the c (ms)/ f(Hz) and I could not really imagine a wavelength that is shorter than the Planck constant. But a related question is the propagation of the E and B fields, which change with respect to frequency, and so what is the limit to their change rate (first derivative) with respect to the speed of light (or looked at another way, the ability of space-time to accommodate that change), all very interesting corner cases like looking at gravity on the event horizon of a black hole.
Anyway, you start going down this rat hole you find a lot of "interesting" ideas (and begin to wonder if maybe you're one of the crazies and you just don't know it yet :-)). There are a lot of easily composed questions in that space, like "Can you conduct a current in a wire that is thinner than an electron?" Which have simple answers like (there is no metal smaller than compressed hydrogen so you can't create such a wire so you can't get there from here,) And less simple answers, "What are the electrical properties of a wire made out of compressed hydrogen then?" (which was the focus of one of the room-temperature superconductor experiments).
You may find, as I have, you sometimes get math that "works" in that you've not violated any mathematical principles in deriving it, but doesn't represent a physically realizable system.
My guess, is that this guy ended up down one of those paths and has a nice, mathematically sound, derivation which, if realized into a system, would have some pretty interesting attributes. And yet the tricky bit is that last one. Sort of the mass-less pulley problem. So many interesting things are possible if you can precisely bend (or smooth!) spacetime, but how you get there from here is a still strictly in the realm of science fiction.
- seiferteric 6y ago> "is there a maximum RF frequency?" Isn't this already pretty well understood? For photons, E=h*f, so if you get high enough energy you will start to see pair production happening?
- srl 6y agoIt is pretty well understood, but the answer is the opposite (following from special relativity). You can take an ordinary low frequency photon, and just observe it while moving arbitrarily close to the speed of light, and the frequency of the photon will appear arbitrarily large. Pair production won't happen until two photons collide, with a large /relative/ momentum. So if they have the same frequency and are traveling in the same direction, no pair production. But, you're absolutely correct in the case of /astrophysical/ photons. A high-energy astrophysical photon will have to pass through, among other things, the background of CMB radiation, and that gives plenty of opportunities to pair-produce, so there is in fact a cutoff to the spectrum of photons we expect from far-away events.
- seiferteric 6y agoWould a high enough energy photon also turn into a black hole?
- jfengel 6y agoPrecisely. That's what the Planck length is: the wavelength of a photon that would be its own black hole. We can't know what happens there without applying both general relativity and quantum mechanics simultaneously, but when you try, you get divide-by-zero errors (singularities). So it's not a limit of the universe, exactly, but it is a limit to what we can know about the universe with our current theories.
- ford_o 6y agoWhat are some interesting things that could be done, if we could bend spacetime?
- WJW 6y agoDepending on how you can bend it, construction of Alcubierre fields allows faster-than-light travel. If you can bend it really precisely, even wormhole construction might not be out of the question. On a lower scale, star trek like forcefields and "perfect" cloaking fields would be possible by bending all light/force carrying particles around an object.
- jcun4128 6y agoIf you looked at it head on and something was in a bubble deflecting light around it, could you tell that it's there because that light takes longer to get through/around relative to the immediate surrounding. Probably still not perceptible.
- ChuckMcM 6y agoOne of the fun ones would be communicating via gravity wave, also it make the Alcubierre "warp drive" possible.