3 ms·

Let the radius of the earth be R. Say you want to send a message from the north pole to the south pole. If you use radio waves that travel around the earth, th

by zodiac 5y ago

Let the radius of the earth be R. Say you want to send a message from the north pole to the south pole. If you use radio waves that travel around the earth, the shortest distance they can travel is πR ≈ 20,000km. If you use neutrinos that travel through the earth, the shortest distance is 2R ≈ 12,700km. So the advantage is about 7,300km (or in time units, 25ms ≈ 7,300km / (the speed of light))

hungryforcodes 5y ago
Fair enough, your calculation seems valid. But my point still stands -- are we going to build enormous LHCs all over the world to get a (maximum) 24 millisecond advantage in global communications via neutrinos?!
- ithkuil 5y ago
  I assume the story is "if we find a magic new tech that is otherwise similar to our existing tech in terms of cost effectiveness, size, bandwidth, reliability, etc, and it also could pass straight through earth, then we could shave off 25ms and that would be useful"
- zodiac 5y ago
  > If there were a way to reliably detect neutrinos in sufficient quantities they'd be ideal since you could send messages through the earth and at near light speed, I suppose. > As opposed to how we communicate now globally? From this interaction I thought you'd missed the point that "send messages through the earth" is something we're currently not doing. Of course you're right that the "if there were a way to reliably detect neutrinos" is doing a lot of work.
db48x 5y ago
You’re talking about using gigawatts of power, and detectors that weigh in at thousands of tons, in order to send a signal best measured in bits per decade. It’s an idiotic suggestion; fiber optics beat anything based on neutrinos hands–down. Authors who make their aliens use neutrino communications are idiots. But that’s ok, most authors are idiots, and most of them stopped taking physics in high school. Authors who take physics seriously are quite rare, even in the science fiction genre. If you want a book written by someone who knows some real physics, read The Clockwork Rocket by Greg Egan. He changed one simple law of physics, worked out the consequences for quantum mechanics and relativity, made up some plausible–enough biology, and wrote a series of books in the resulting universe. The characters in the book have to discover or teach each other those laws, so the book is actually a pretty decent way to learn something of the laws of our own universe too. He wrote a huge amount of supplementary material as well, going into all the details. Truly an astounding accomplishment.
- hungryforcodes 5y ago
  Awesome-- I've heard of him, but didn't know he had done so much detailed work on his stories. I'll check him out.
- zodiac 5y ago
  I am well aware of the "disadvantages" (to put it mildly) of hypothetical neutrino-based communications and I never suggested that they could viably replace EM-based communication

by zodiac 5y ago

hungryforcodes 5y ago

Fair enough, your calculation seems valid. But my point still stands -- are we going to build enormous LHCs all over the world to get a (maximum) 24 millisecond advantage in global communications via neutrinos?!

ithkuil 5y ago
I assume the story is "if we find a magic new tech that is otherwise similar to our existing tech in terms of cost effectiveness, size, bandwidth, reliability, etc, and it also could pass straight through earth, then we could shave off 25ms and that would be useful"
zodiac 5y ago
> If there were a way to reliably detect neutrinos in sufficient quantities they'd be ideal since you could send messages through the earth and at near light speed, I suppose. > As opposed to how we communicate now globally? From this interaction I thought you'd missed the point that "send messages through the earth" is something we're currently not doing. Of course you're right that the "if there were a way to reliably detect neutrinos" is doing a lot of work.

db48x 5y ago

You’re talking about using gigawatts of power, and detectors that weigh in at thousands of tons, in order to send a signal best measured in bits per decade. It’s an idiotic suggestion; fiber optics beat anything based on neutrinos hands–down. Authors who make their aliens use neutrino communications are idiots. But that’s ok, most authors are idiots, and most of them stopped taking physics in high school. Authors who take physics seriously are quite rare, even in the science fiction genre. If you want a book written by someone who knows some real physics, read The Clockwork Rocket by Greg Egan. He changed one simple law of physics, worked out the consequences for quantum mechanics and relativity, made up some plausible–enough biology, and wrote a series of books in the resulting universe. The characters in the book have to discover or teach each other those laws, so the book is actually a pretty decent way to learn something of the laws of our own universe too. He wrote a huge amount of supplementary material as well, going into all the details. Truly an astounding accomplishment.

hungryforcodes 5y ago
Awesome-- I've heard of him, but didn't know he had done so much detailed work on his stories. I'll check him out.
zodiac 5y ago
I am well aware of the "disadvantages" (to put it mildly) of hypothetical neutrino-based communications and I never suggested that they could viably replace EM-based communication