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2019-04-26
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john00:04:27

Not so related but also interesting factoid: the front of a "slow" radio wave actually travels through a vacuum just as fast as the front a light wave. It's just the frequency of the wave that is faster or slower than light. I always thought radio waves actually arrived at their destination later than light waves.

Mno00:04:30

Huh.. I never thought about that.. but yeah it’s electromagnetic radiation so it should go at the same speed as other electromagnetic radiation. 🤔

andy.fingerhut01:04:13

I had never heard of a radio wave referred to as "slow". Perhaps because the frequency is so much lower than visible light?

john02:04:53

Yeah, the fact that they're all the same kind of waves, just at different freqs, had escaped me for a long time. I just figured I'd search up the answer the other day and was pleasantly surprised.

john02:04:11

I wonder if you could get higher speed communication with low frequency radio waves just by sending lots of separate new waves in a short time 🤔 Anybody know about radio waves and if that's been tried?

john02:04:11

I wonder if you could get higher speed communication with low frequency radio waves just by sending lots of separate new waves in a short time 🤔 Anybody know about radio waves and if that's been tried?

valtteri04:04:11

Information is carried over radio waves by either altering amplitude or frequency. This is also the difference between A.M (Amplitude Modulation) and F.M (Frequency Modulation) radio. http://www.qrg.northwestern.edu/projects/vss/docs/communications/1-how-is-data-put-on-radio-waves.html

john04:04:16

But is the arrival of the wave, regardless of its frequency or amplitude, not a piece of information that we can use?

john04:04:27

Or the lack of a wave?

john04:04:09

If I send or don't send a 1 hz wave, 10 times a second, can I convey 10 bits of information?

john04:04:30

using 10 separate antennas, let's say

valtteri04:04:06

If you use same frequency the waves interfere with each other

valtteri04:04:25

If you had several waves on that same frequency it would alter how electrons shift from + to - in the antenna and you’d get just noise.

john04:04:32

Would they interfere even if they are sent at 10ths of a second increments apart from each other?

john04:04:42

Plus, who cares what the frequency is? I just want to know if a wave is inbound on a given 10th of a second or not. I don't care what it's frequency or amplitude is (in this hypothetical)

valtteri04:04:31

As mentioned before, radio waves are just like any other electromagnetic waves. So there’s quite a lot of noise and you need to be “listening” to some particular frequency to make any difference.

john04:04:00

Hmmm. I guess, for the wave to push the voltage down the conductor, you'd need an entire wave cycle to complete.

valtteri04:04:59

Yeah, and this whole wave thing is actually just a useful abstraction. What there actually happens is best described by quantum mechanics. And I’m just a hobbyist. 🙂

valtteri05:04:52

But basically the antenna is receiving all kinds of noise and at the receiver end you need to filter the other bands except the ones you’re listening to. Therefore you cannot be listening to arbitrary waves unless you’re in a very controlled environment.

john05:04:03

Yeah, I suppose the detector is detecting the motion of the wave, not the front of the wave.

valtteri05:04:36

You can think it like that yes. But actually such a thing as “the front of the wave” doesn’t exist in classical mechanical sense.

john05:04:58

I mean the part of the wave that moves at 186,000 miles per second

valtteri05:04:05

Ok we’re going deeper. 🙂 So basically electromagnetic waves carry photons and they are actually discrete chunks.

john05:04:01

Except when they're not, right? 😉

valtteri05:04:10

Or actually we’re entering the QM world here. Photons seem to act as both waves and particles. And that’s where the weird part begins.

john05:04:12

Are all electromagnetic waves photons? Including 1hz radio waves?

valtteri05:04:14

Yes. Basically everything that can travel at the speed of light must have no mass. And particles that have no mass are basically photons or gluons.

john05:04:15

Seems to me if we could just detect that chunk, without having to care about its frequency, we could get 186000 mps communication that could go across the globe, using a low frequency wave to carry it.

john05:04:06

But like you say, we wouldn't be able to distinguish it from all the other chunks

valtteri05:04:34

And to add more confusion, when we’re talking about ‘the speed of light’ we’re actually talking about ‘the speed of causality’ traveling through the universe.

valtteri05:04:15

You can’t distinguish one photon from another.

john05:04:36

Right, so that would also mean that the particles inside atoms rotate no faster than the speed of light as well, right?

valtteri05:04:18

Electrons can ‘shift’ from orbit to another in zero time

john05:04:21

makes sense as a measure of causality then

valtteri05:04:42

Time itself is super interesting concept

john05:04:46

mmm. Sounds like an automaton 😉

valtteri05:04:16

Most of the laws of physics are symmetric to time. They don’t actually care which direction time flows

valtteri05:04:31

Entropy being the difference maker.

john05:04:49

jumping through space in zero time sounds like an automaton, rather than classical mechanics

valtteri05:04:07

Yeah in classical mechanics or in general relativity jumps don’t just happen. You can bend space&time to the extremes though.

valtteri05:04:19

In quantum mechanics jumping happens and that’s super weird.

john05:04:11

Yeah, things can spontaneously jump through barriers allegedly, right?

john05:04:08

Anyway, I gotta retire for the night, but thanks for the insight and clarifications

valtteri05:04:40

Yeah there are a few known phenomena where the state of a particle can change “instantly” or the position might seem like it was determined beforehand even though it logically would be impossible.

valtteri05:04:00

Thanks for the convo! Good nights!

elendili06:05:49

Thank you both)

john02:04:03

Hah, interesting "7.83 Hz [is] the frequency at which the wavelength equals the circumference of the Earth" - https://en.wikipedia.org/wiki/Extremely_low_frequency#Schumann_resonances

Roberto Rodriguez Jr08:04:12

is this place alive? ive been on 3 diff chan and nothing :(

orestis08:04:12

Very much alive, just Europeans tend to be little bit more shy 🙂

orestis08:04:53

@rob.rodz.jr9 things might be a little bit async, but low-traffic channels are monitored by some very helpful and kind people — so just ask something and see what happens.

Roberto Rodriguez Jr08:04:23

i love kind folks. im in Georgia USA. never really been able to make technology minded friends.

eggsyntax16:04:25

This is definitely the right channel for social chat 🙂 Although as Orestis says, daytime US tends to be the busy hours around here. #beginners is definitely a good one if you're new to Clojure and have questions. Welcome!

Roberto Rodriguez Jr17:04:50

very nice :) thx u for the response

Roberto Rodriguez Jr08:04:26

well im spent for the night. ttyl hopefully.

Roberto Rodriguez Jr17:04:01

Morning everyone lol

Roberto Rodriguez Jr17:04:03

new to slack and clojure and front end dev, well pretty much any kind of real dev... im a superuser if u will

seancorfield17:04:15

Welcome @rob.rodz.jr9 -- you should find daytime US much chattier 🙂

Roberto Rodriguez Jr17:04:12

@seancorfield yes and thats real good cuz i cant wait to have live convo with someone like me

Roberto Rodriguez Jr17:04:05

id prob look like a kid in a candy store if i was ever attending a conference with a ton of smart people

seancorfield17:04:26

Conj just got announced for November 21-23 in Durham, NC -- it's always a blast!

Roberto Rodriguez Jr18:04:35

i break even weekly man, the struggle is real.... i wish i could do some kind of remote work just to b able to go

chrisulloa21:04:20

@rob.rodz.jr9 There are opportunity grants for Clojure/Conj, maybe you qualify for one? http://2018.clojure-conj.org/opportunity-grants/

Roberto Rodriguez Jr21:04:27

no to figure out what underrepresented group im part of

Roberto Rodriguez Jr21:04:15

@christian.gonzalez gracias for the info

Roberto Rodriguez Jr21:04:52

slack is pretty cool, first time using it