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Comment by madengr | Hacker News Reader

Meh, they need to use gravity waves; not affected by dielectric constant. Maybe a spinning mass that is frequency modulated. I just need to patent that and be funded by some wealthy traders.

Seriously though, I’m surprised they are not using direct path, deeply buried air-line coax. Has to be TEM propogation or else group delay is too high, so rectangular waveguide won’t work. Circular may work; I need to brush up on my EM.

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Eh, too much energy required for gravitational waves. But I think that particle accelerators and giant neutrino detectors have been at least half seriously considered. I think that, although the impulse pretty much travel at c and can tunnel though anything, the lenght sampling period of the impulse required to distinguish it from noise would defeat the latency advantage.

I always thought neutrinos is how aliens would contact other aliens, not radio waves

I can't wait of the era of quantum entanglement HFT /s

Thanks to spooky action, I can lose my money before I even place the trade!

Too late (patenting that gravity idea, that is) - John D. Kraus suggested precisely that in an appendix to his magnificent book on all things antennas, aptly named 'Antennas'.

I do believe he concluded it was not the most practical of communication schemes, though. :)

(Edit - corrected name of author; I had originally called the poor guy Erwin Klaus)

I could find nothing on Erwin Klaus or his book Antennas. Can you point a guy in a direction?

My apologies; a double typo -KRAUS. (Courtesy of my SwiftKey keyboard app), first name John. (Erwin Kraus is an acquaintance of mine; no idea how that short circuit occurred.)

John D. Kraus - Antennas.

Big Ear is a good book; essentially his autobiography.

Many thanks!

edit: Holy, this book is beyond me— but that's exactly what I wanted.

For other curious parties, it's on Archive.org: https://archive.org/details/Antennas2ndbyjohnD.Kraus1988

On the off chance you were looking for a book on antennas which gives you lots of ideas without getting too carried away with maths, Karl Rothammel's 'Antennenbuch' is probably the one to beat - he's basically nicked every antenna idea ever published and put it in a massive compendium. As an added bonus, it will teach you German if you don't know it already.

To ease your feet gently into the water, you could do a lot worse than picking up a copy of the 'ARRL antenna book' - a blend of theory and practice, giving ideas for a lot of different designs while explaining a bit of the theory behind their function.

Signals interests me in general (top to bottom— including hard and softwares), and I'm trying to get around to deeper physics and maths study around it, but there's only so much time in a day.

If you have any other recommendations, I'll gladly hear them— there's a link to my contact in my profile.

I've just spent a while looking for my old signal processing textbooks, but there was too much piled on top of them (I've moved house three times since I last worked with signal processing... :)

I remember two introductory books which were quite good - Kamen/Heck's 'Signals and Systems' - tells you a bit about the tools of the trade, laplace and fourier transforms, transfer functions, filter design &c - the book was accompanied by a number of MatLab scripts which let you visualise how manipulating properties of a filter affected the output; most useful.

Proakis & Manolakis' Digital Signal Processing was also quite good; both books assume you know your way around engineering mathematics - series, integrals mostly - but in particular Kamen/Heck I remember provoking quite a number of insights from the text alone.

Again, the ARRL may be of some assistance - the radio amateur's handbook has a couple of chapters on the basics of filters, leaning very much against the applied end of things.

I hear good things about Owen's Practical Signal Processing, too, but haven't studied it myself yet; as you say, there's only so much time in a day...

Oh, and steer clear of anything with the phrase 'non-linear' anywhere in the title or blurb. Just don't go there.

That's great. I'd really like if I could spend more time these days learning what I want so I can get into work that I'm happier doing.

Thanks for digging!

Yeah, I suppose the mass needed would only allow a very narrow modulation bandwidth.

That, plus it would demand rather a lot from the power grid, to put it mildly.

Pitch them a series of boxes full of quantum entangled cats. The "driver cat" in jersey can pick the stocks while the "tail cat" in NY executes the trades. Forget Heisenberg, such uncertainties are irrelevant when thrown darts can best the market.

If there is a group on this planet incentivised to perfect neutrino communication, it will probably be HFT.

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