I was wondering if the technology exists where you can send a signal through the earth and measure it from the other side?
>>54895683
you literally just posted it. requires too much energy to be useful outside of scientific research though.
>>54895780
I thought so, but I meant do they set up a sender and a receiver that literally is powerful enough to hear it from the other side of the planet?
>>54895802
well the "sender" is usually just an impact like an explosion or something like pic related for shorter distances.
than you recieve the waves with a seismometer.
>>54895802
If ifrasound and vibrations count as "hearing", nuclear exposions and earthquakes are certainly able to pass through the core to the other side.
>>54895683
there are armature radio groups for low frequency commnication. however, they are restricted on power output because the navy uses those frequencies to communicate with submarines.
>>54895802
Sending data straight through earth is quite impossible
Every transmission right now moves around the outer shell, or through the athmosphere. You can transmit AM radio around the globe when the weather is good.
>>54895880
This is the explanation I was looking for. Thank you anon.
>>54895873
these wouldn't be able to penetrate the whole diameter though would they?
>>54895873
Even the unbelieavably huge and powerful ELF transmitters are no able to penetrate more than a few hundreds of meters. and nothing EM will penetrate the core.
Things like gravity waves and neutrinos could do it but can't be used.
>>54895880
>Sending data straight through earth is quite impossible
Why is that? Seismic vibrators produce P-waves, which can travel through liquids.
Assuming you adjust the signal for reflection and refraction, shouldn't you be able to go through the earth?
Or are the seismic generators not strong enough?
>>54895867
>>54896055
most badass form of communication right here. detonate 2 nukes for "yes" and 1 nuke for "no".
>>54895683
yes but as >>54895780 said its expensive and has huge energy requirements. that's why only scientists use it during experiments, and nuclear subs use it. they have both the money(i.e. equipment) and power to do so
>tl;dr yes but its only used by nuclear subs
I'm thinking using neutrinos will be possible at some point, but not before we can figure out how to reliably detect them.
what's the point though if we have a cable net and a satellite system in place already?
>>54896055
I have no idea really. I just imagine that all the 12000km of material might be too dense, or too spotty/different at places, to properly transmit a signal. It might also be moving around, so you might not know where your signal eventually ends up at, or how far it spreads out.
It is also slow
http://eqseis.geosc.psu.edu/~cammon/HTML/Classes/IntroQuakes/Notes/waves_and_interior.html
for p-waves:
>They typically travel at speeds between ~1 and ~14 km/sec
not considering how straight you can get your transmission to go
>>54896208
Oh and lets not forget that there's little area where you would be able to communicate from human to human on two different sides of the earth. Most of the time you end up in the ocean.
>>54895683
If you had an invincible storage medium, you could stick it where the tectonic plates collide and let it get sucked into the earth. Should emerge somewhere in a couple million years.
>>54895683
Yup, with extra low frequency(ELF) radio you can send a signal to anywhere on earth. Except you need a a FUCKING HUGE antenna to generate such low frequencies, and because the wavelength is SO FUCKING HUGE compared to your antenna you get efficiencies that are horrible.
The US navy's Clam Lake facility uses 2.6 MEGAWATTS to transmit a measly 8 watts! HAARP was fucking cool because it tried to solve these problems. Fuck making a real antenna kilometers long, let's just make a huge fucking antenna out of plasma in the ionosphere!
Oh and because the frequency is so low, the bandwidth is way, way, way low. Clam lake can supposedly transmit a 3 letter code group in 15 minutes!
Now there are ways to get higher bandwidth. One is to drill a big fucking hole and route fiber through it. The other more practical and ridiculous way is to use neutrinos.
Neutrinos are weird fucking particles that pass through fucking everything. A light year of lead will only stop half of the neutrinos going through it. They'll go straight through the earth no problem. But this is the problem, because they pass through everything, they're hard to detect!
So to detect em' you gotta send a lot. Oh and even the slightest bit of stray radiation makes it hard to detect. Most neutrino detectors are built in places that are deep and dark, to filter out this radiation.
Well guess what's also deep and dark? The motherfucking ocean!
Some crazy motherfuckers have proposed communicating with submarines using neutrinos:
http://www.physics.ucla.edu/~hauser/neutrino_communication_paper/siljah_mod.htm
Only problems are you gotta know where the sub is pretty fucking exactly and no fucking way can you mount a neutrino transmitter on a sub, so you can't get two way communication, but you can't get that with ELF communication either.
>>54896055
nice dubs
No it'll fucking work. You just gotta use low frequencies that won't attenuate much traveling through the mantle, and a facility like LIGO to detect them.
LIGO is a gravitational wave observatory, AKA, world's unintentionally most sensitive seismograph. If a tree falls in a forest it shows up as noise on LIGO.
Another crazy mother fucker showed that we could use a facility like LIGO to get data back from a probe deep inside Earth even if the probe is only transmitting with like 10 watts of power:
http://www.cmp.caltech.edu/refael/league/to-the-core.pdf
This does, however, suck compared to ELF. Now you not only have a problem with bandwidth, but latency. The signal goes as fast as the speed of sound, which is pretty fucking slow compared to light speed.
>>54895952
ELF can have a wavelength the size of the goddamn Earth. C/60 Hz = 5000 KM, that ain't gonna disperse much
>>54895683
Neutrinos
what if you run a rope around the entire planet and then tug on it to communicate
>>54897148
What if the rope was made out of copper and instead of tugging on the whole thing you just tugged on the electrons a little?
>>54897148
>speed of sound
>30 hour ping times
Did you really think this through?
>>54897210
how would you do that smartass
>>54897237
its instant moron
>>54897274
>instant
>rope has no elasticity
>>54897274
>he doesn't know about electricity
>current year
>>54895683
It's called a Nuclear Bomb
What about if you built a really big magnet on one side of the planet? Would the magnetism penetrate the core?
>>54897401
You would probably rip the core out of the earth, or the magnet would just get stuck and slowly dig it's way into the ground
>>54895683
It would be very painful
>>54897148
deformation waves propagate near the speed of sound
>>54896483
this is the only correct post. ELF can go through the earth because of its wavelength. you can communicate with anyone on the planet with it and you don't need to build a huge antenna, the earth itself can be used as the antenna.
>>54900412
U U U U
Maybe in the future with neutrinos?
>>54895683
It would generate so much noise near the center of the Earth. And all the magma with a lot of metals distort waves.
>>54896483
>>54902335
Even at 60 Hz you don't have unconditional penetration.
The wave do get around the earth, but they still can't get through it.
I mean, even the 75Hz US ELF sub communication signal can't be received deeper than a a few tens/couple hundred meters.
>>54895880
actually, tachyons (maybe) and gravitational waves, but the cost would be prohibitive
>>54895683
Neutrinos. The technology exists...somewhat.
>>54896483
>If a tree falls in a forest it shows up as noise on LIGO.
What if a fat girl falls in a bar?
