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'Electric Earth' Could Explain Planet's Rotation

Soulskill posted more than 2 years ago | from the thought-it-was-gas-powered dept.

Earth 153

sciencehabit writes "When it comes to Earth's rotation, you might think geophysicists have pretty much everything figured out. Not quite. In order to explain some variations in the way our planet spins, Earth's mantle — the layer of hot, softened rock that lies between the crust and core — must conduct electricity, an ability that the mantle as we know it shouldn't have. Now, a new study (academic paper) finds that iron monoxide, which makes up 9% of the mantle, actually does conduct electricity just like a metal, but only at temperatures and pressures found far beneath the surface."

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And that's why (2, Funny)

Anonymous Coward | more than 2 years ago | (#38776283)

That's why I bought a Saturn.

Velikovsky (-1)

russotto (537200) | more than 2 years ago | (#38776289)

So does this mean people will start taking Immanuel Velikovsky [wikipedia.org] seriously? I mean people aside from James Hogan?

Naa...

Re:Velikovsky (0)

Anonymous Coward | more than 2 years ago | (#38776561)

I can't tell if your being Ironic or not. If so then it fell a little short, for me at least. If not, what the hell does this have to do with Immanuel Velikovsky's crack pot ideas?

Re:Velikovsky (-1)

Anonymous Coward | more than 2 years ago | (#38776667)

I can't tell if you know how to spell "you're" or not....

Re:Velikovsky (1)

binarylarry (1338699) | more than 2 years ago | (#38777159)

they're they're know

arXiv link (5, Informative)

fishicist (777318) | more than 2 years ago | (#38776291)

Full text available on the arXiv, for those without a subscription to PRL: http://arxiv.org/abs/1112.5068 [arxiv.org]

Magnetic field + conductor = Electricity? (5, Interesting)

atchijov (527688) | more than 2 years ago | (#38776295)

Is there any electricity flowing and if there is, how can we harvest it?

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38776327)

It should be easy to harvest it; you just stop the planet's spin and then... Oh, you don't know how to do that? And your species is dependent on the planet's magnetic field because you can't stand up to much radiation? Well then you can't harvest that current... We Q could do it, but don't need any puny electricity.

Re:Magnetic field + conductor = Electricity? (5, Insightful)

NoobixCube (1133473) | more than 2 years ago | (#38776351)

Electricity is remarkably lazy, and doesn't do anything it isn't forced to do. It will always follow the path of least resistance, and will never flow from a point of lower voltage to higher (that would be like water flowing up hill). If there's electricity flowing, you have to ask what's causing it to flow. What's increasing the voltage between the two points? If you harvest the electricity without unerstanding why it's flowing in the first place, you won't know what the consequences may be.

Re:Magnetic field + conductor = Electricity? (2)

AmberBlackCat (829689) | more than 2 years ago | (#38777245)

Perhaps the original question could be rephrased to, what can we plug into the mantle that electricity will travel through easier than the mantle itself? But I'd have to wonder, if there is some way to harvest electricity from it, would that have a consequence similar to what harvesting water has done to the Colorado River [wikipedia.org] .

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38777313)

and will never flow from a point of lower voltage to higher

Electrons have a negative charge. They move from negative to positive.

Re:Magnetic field + conductor = Electricity? (1)

CSMoran (1577071) | more than 2 years ago | (#38777371)

and will never flow from a point of lower voltage to higher

Electrons have a negative charge. They move from negative to positive.

Ions, including those positive, can conduct electricity too.

Re:Magnetic field + conductor = Electricity? (1)

NoobixCube (1133473) | more than 2 years ago | (#38777683)

Voltage isn't the same thing as charge, it's an expression of potential energy; that is to say, the difference in charge between two places. High voltage means electrons are colleted at one place and somehow absent from another. You're not going to take MORE electrons from the low point, obviously.

Re:Magnetic field + conductor = Electricity? (5, Informative)

dak664 (1992350) | more than 2 years ago | (#38777749)

Path of least resistance does not apply to electricity. It follows every field gradient and takes every path as fast as it can. The current through each path is limited by the reduction of the gradient caused by the charge already along the path, a.k.a. resistance.

Re:Magnetic field + conductor = Electricity? (1)

jamesh (87723) | more than 2 years ago | (#38778635)

Path of least resistance does not apply to electricity. It follows every field gradient and takes every path as fast as it can. The current through each path is limited by the reduction of the gradient caused by the charge already along the path, a.k.a. resistance.

The "path of least resistance" explanation always bugged me too when I heard it in high school... if it was true, all the electricity in your house (and by extrapolation, your street) would only flow through the appliance with the least resistance and would refuse to flow though all the other appliances, which is clearly not the case.

The internal resistance of the battery supplying the power might make it look like this is what's happening if you put a very low resistance device in parallel with a higher resistance device, but it's still wrong.

Re:Magnetic field + conductor = Electricity? (5, Interesting)

Ethanol-fueled (1125189) | more than 2 years ago | (#38776483)

Tesla had that all figured out a little less than a century ago.

Of course, his work was buried so Edison could make a buck with inferior technology.

Re:Magnetic field + conductor = Electricity? (4, Informative)

John Hasler (414242) | more than 2 years ago | (#38776737)

Of course, his work was buried so Edison could make a buck with inferior technology.

There's a problem with your theory. His name was George Westinghouse.

Re:Magnetic field + conductor = Electricity? (-1)

Anonymous Coward | more than 2 years ago | (#38777957)

His name was George Westinghouse.

I heard that mother fucker had like...30 god damn dicks

Re:Magnetic field + conductor = Electricity? (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#38778761)

Relax. Dicks were security ppl back 100 years ago. Now, it has a different meaning. It is like in 100 years, everybody on this planet will think that brits were all gay. They are also running around looking for fags to put in their mouths.

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38776495)

So, humanity... you have a gigantic fusion reactor floating right in front of your faces each and every single day... ...and yet you are constantly thinking about
- using energy that is required for a process that keeps you alive (like slowing down earth's rotation)
- finding the rarest resources on earth with useful energy in them and using them as your main fuel (uranium, fossil fuels, etc)
- being "green" by burning your own food, one of the most inefficient things to grow and process in the whole world.,

*warp 10 relativistic reverse double picard facepalm*
I don'. want to live on this planet anymore...

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38777391)

Oh, it's all so simple! Obviously what we should be doing is burning the high energy output COMMON elements like silicon and oxygen! It all makes sense now!

Re:Magnetic field + conductor = Electricity? (1)

cynyr (703126) | more than 2 years ago | (#38777517)

So, care to work out how to power NYC with your "floating gigantic fusion reactor"? The best number I can find is 5GW (must be the "instantaneous" load of the city). How much land do you need to provide that sort of power with the sun? What will effect will reducing the amount of light that makes it there cause? How do you provide the required night time load?

This is not to say that not covering the roofs/side/etc of all building in NYC with solar panels is a bad idea, or worthless, just that it won't provide 100% of the power with the sort of availability that we are used to. We will should try to diversify our power generation methods.

Re:Magnetic field + conductor = Electricity? (-1)

Anonymous Coward | more than 2 years ago | (#38777605)

I'm equally curious how you fly a 747 with this floating fusion reactor.... OP is a species of Nutter, an Energy Nutter. Someone so clueless about basic physics and engineering that fantasy becomes fact.

Re:Magnetic field + conductor = Electricity? (1)

WCguru42 (1268530) | more than 2 years ago | (#38778229)

You can spin an engine with electricity. Propeller airplanes are powered by rotating engines. Therefore, you can make an airplane that can fly with electricity and not fuel.

It might not be a 747 but it'll still fly.

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38778419)

The problem with electricity for propellers or turbines is that if there's any sort of resistance to the propeller or turbine (say, goose in the prop or turbine intake), your electrically-powered prop has a pretty good chance of stopping altogether. Gas-powered props/turbines are more likely to continue to operate - you know, V = nRT/P.

Re:Magnetic field + conductor = Electricity? (1)

EdIII (1114411) | more than 2 years ago | (#38778475)

If the fusion reactor floats... you are already flying. Just attach some small propellers, add a few seats and a dining car... and you have a luxury blimp.

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38777745)

i kind of agree with you on the first 2 points but there must be some terrible typos or something in that 3rd point.

- being "green" by burning your own food, one of the most inefficient things to grow and process in the whole world

however, i can't imagine one that would still make this statement make sense...unless you are actually an alien.
as a human being, i don't care how inefficient growing food is...how else am i going to eat?

Re:Magnetic field + conductor = Electricity? (0)

Anonymous Coward | more than 2 years ago | (#38778487)

Put the comic books down and join us in the human race.

Bad Idea (0)

Anonymous Coward | more than 2 years ago | (#38776775)

Is there any electricity flowing and if there is, how can we harvest it?

Of course, if this same electricity is creating Earth's magnetic field then harvesting it would weaken the field that's protecting us from being constantly bombarded by charged particles and would probably wipe out most (if not all) life found on the surface.

Re:Bad Idea (0)

Anonymous Coward | more than 2 years ago | (#38778693)

Yes, I was going to post something like this. Taking energy from earth's magnetic field would be a bad idea.

Re:Magnetic field + conductor = Electricity? (1)

lightknight (213164) | more than 2 years ago | (#38778729)

No. Don't even pursue this line of inquiry.

this is all fine and dandy (5, Insightful)

circletimessquare (444983) | more than 2 years ago | (#38776309)

as long as this story doesn't bring out the electric universe trolls

Re:this is all fine and dandy (1)

Mitchell314 (1576581) | more than 2 years ago | (#38776387)

What about us magnetic universe trolls?

Re:this is all fine and dandy (1)

circletimessquare (444983) | more than 2 years ago | (#38776459)

stand in line behind the quantum gravity trolls

Re:this is all fine and dandy (0)

Anonymous Coward | more than 2 years ago | (#38776657)

It's quantum *attraction* you insensitive clod. And it's an emerging science where we investigate how the principle of attraction influences the outcome of seemingly random quantum phenomena.

http://en.wikipedia.org/wiki/The_Secret_%282006_film%29

Re:this is all fine and dandy (1)

circletimessquare (444983) | more than 2 years ago | (#38776695)

LOL

Nikola (0)

Anonymous Coward | more than 2 years ago | (#38776319)

Tesla knew that already.

Re:Nikola (-1)

Anonymous Coward | more than 2 years ago | (#38776447)

Yes, but Tesla didn't know anything Chuck Norris didn't teach him.

Re:Nikola (0)

Anonymous Coward | more than 2 years ago | (#38776895)

Yes, but Tesla taught Chuck Norris the Roundhouse kick during a sparring match in Johannesburg. Chuck Norris instantly perfected it. And that's why Tesla is dead.

Not to be confused with.... (4, Informative)

tverbeek (457094) | more than 2 years ago | (#38776321)

Not to be confused with the Electric Universe Theory [holoscience.com] .

Re:Not to be confused with.... (2)

cyberchondriac (456626) | more than 2 years ago | (#38776641)

Being unfamiliar with this "theory", I followed the link. Holy hell, do they beat around the bush! I still don't have any idea what they're talking about (other than claiming modern science is deeply fragmented and flawed), but I read enough to decide I don't care.

Re:Not to be confused with.... (1)

sortius_nod (1080919) | more than 2 years ago | (#38776961)

I switched off when I saw the Lovecraft quote.

Re:Not to be confused with.... (3, Funny)

EdIII (1114411) | more than 2 years ago | (#38778511)

I switched off when I saw the Lovecraft quote.

Of course it did. That is a defense mechanism because your mind is to puny to comprehend and/or confront the madness of the abyss......

Re:Not to be confused with.... (1)

ceoyoyo (59147) | more than 2 years ago | (#38776979)

I'm not surprised. They don't know what they're talking about, so why would you be able to figure it out?

Time was when any astronomical or earth science story on /. would bring out legions of very sincere electric universe crazies.

Re:Not to be confused with.... (1)

PopeRatzo (965947) | more than 2 years ago | (#38776647)

Not to be confused with the Electric Universe Theory.

I'm a little bit familiar with the Electric Universe Theory and the way some comparative mythologists such as David Talbott and Troy McLachlan have incorporated the Electric Universe into their very interesting work. But I'm not clear on why this story is not connected with the EUT.

I'm not a physicist or an astronomer, so if you know a little bit about this can you try to clarify? My field was the analysis of texts, so I can deal with the comparative mythology piece, but I get lost pretty easily in the hard physics weeds.

By the way, the book by Troy McLachlan, Saturn Death Cult is one of my favorite books from 2011. Even if you believe EUT is crackpot stuff (and it well may be), it's a riveting read.

Re:Not to be confused with.... (1)

tverbeek (457094) | more than 2 years ago | (#38777125)

It's not connected in the same way that the Jimi Hendrix album Electric Ladyland is not connected. By being about something completely different, but it just happens to start with the same word. :)

Re:Not to be confused with.... (0)

Anonymous Coward | more than 2 years ago | (#38777941)

Not sure if what I heard once were central doctrines of the electric universe or personal variants, but it seemed an important part required finding large currents flowing through the universe. As part of this, large currents flowing through the Earth were connected to a bunch of geological phenomenon (for a loose definition of "connected," at least mentioned in the same sentences a lot). So it might not be surprising to seem electric universe people jumping all over a story like this that makes it easier to have currents go through the Earth, even if it is only the interior and what they needed was for a way for currents from space to flow through the Earth.

Re:Not to be confused with.... (1, Informative)

PopeRatzo (965947) | more than 2 years ago | (#38778299)

It's not connected in the same way that the Jimi Hendrix album Electric Ladyland is not connected.

You haven't listened to Electric Ladyland the way I've listened to Electric Ladyland.

It's connected to everything. Listen to side three after a couple of hits of the orange sunshine and tell me it's not.

I remember one time, I was out on the back porch of my friend's place up in Wisconsin, and I was staring up at the night sky just as I was peaking and and about halfway through side 3, when "1983... (A Merman I Should Turn to Be) " is really starting to take off and you could see the Milky Way and Hendrix is like "...giant pencil and lipstick-tube shaped things continue to rain and cause screaming pain and the arctic stains from silver-blue to bloody red as our feet find the sand..."

Man, everything is connected to everything.

Don't tell me about no "electric universe theory". Dude, I live there. :)

Iron Monoxide? (5, Informative)

Doctor Morbius (1183601) | more than 2 years ago | (#38776333)

FeO is Ferrous Oxide not Iron Monoxide.

Re:Iron Monoxide? (5, Funny)

tqk (413719) | more than 2 years ago | (#38776401)

FeO is Ferrous Oxide not Iron Monoxide.

The topic at the moment is geology, not chemistry. Try to keep up.

Bloody chemists. Grumble, mumble, ...

Re:Iron Monoxide? (1)

Hognoxious (631665) | more than 2 years ago | (#38777363)

The topic at the moment is geology, not chemistry.

You mean the history of chemistry. Suffixes like -ous and -ic and prefixes like per- and sesqui- were dropping out of use (i.e. the newer textbooks tended to use Roman numeral in brackets notation) when I last did chemistry twenty-some years ago.

GP probably still believes in Phlogiston.

Re:Iron Monoxide? (1)

yndrd1984 (730475) | more than 2 years ago | (#38778091)

GP probably still believes in Phlogiston

Phlogiston does exist, it's a nickname for highly entropic kinetic energy.

Re:Iron Monoxide? (1)

Whiteox (919863) | more than 2 years ago | (#38778677)

Yep and the AEther in the heavens is dark /matter energy,

Re:Iron Monoxide? (1)

Sevalecan (1070490) | more than 2 years ago | (#38776451)

My CHM 111 professor would get a kick out of this. He's always giving biologists a hard time, but he makes fun of geologists as well.

Also, I prefer iron(II) oxide personally.

Re:Iron Monoxide? (4, Informative)

Anonymous Coward | more than 2 years ago | (#38776703)

They are synonyms according to Chemical Book [chemicalbook.com] .

Re:Iron Monoxide? (4, Funny)

istartedi (132515) | more than 2 years ago | (#38776951)

As long as it isn't dihydrogen monoxide. That stuff's dangerous!

Re:Iron Monoxide? (0)

ceoyoyo (59147) | more than 2 years ago | (#38776997)

Iron monoxide would be the modern standardized name.

Re:Iron Monoxide? (0)

Anonymous Coward | more than 2 years ago | (#38777383)

I'm pretty sure that's iron(II) oxide. The naming scheme in "iron monoxide" is generally used for molecules, which have covalent bonds: carbon dioxide. Iron(II) oxide is an ionic compound, so it's named differently.

Re:Iron Monoxide? (2)

Tacvek (948259) | more than 2 years ago | (#38777525)

The preferred name would indeed be "iron(II) oxide". The name "iron monoxide" is however correct for a purely stoichiometric name. Such a name does not indicate the exact number of each element in a molecule, only the relative numbers. It also does not indicate the bonding in any way.

See the IUPAC Red Book 2005 for more details.

Re:Iron Monoxide? (5, Funny)

LtGordon (1421725) | more than 2 years ago | (#38777009)

FeO? That stuff is ugly.

Re:Iron Monoxide? (0)

Anonymous Coward | more than 2 years ago | (#38777355)

+1 spanish joke

Re:Iron Monoxide? (0)

Anonymous Coward | more than 2 years ago | (#38777361)

Muy chistoso, pero creo que la mayoria de personas Slashdot no van a entender.

(yes, obviously, not my first language, and barely my second)

Re:Iron Monoxide? (1)

grcumb (781340) | more than 2 years ago | (#38777427)

FeO is Ferrous Oxide not Iron Monoxide.

And FeB is Ferrous Bueller. What's your point?

Re:Iron Monoxide? (1)

drainbramage (588291) | more than 2 years ago | (#38777585)

Are you sure it isn't the second month of the year?

Re:Iron Monoxide? (4, Informative)

Tacvek (948259) | more than 2 years ago | (#38777457)

FeO has not been Ferrous Oxide in many years.

As of the IUPAC Redbook 2005, the preferred name would be "Iron(II) Oxide", however the name "Iron Monoxide" is a valid stoichiometric name for the substance.

The classic name "Ferrous Oxide" is no longer considered acceptable. I quote from Table III's second definition of the suffix "-ous":

Ending formerly added to stems of element names to indicate a lower oxidation state, e.g.
ferrous chloride, cuprous oxide, cerous hydroxide. Such names are no longer acceptable.

The "-ous" suffix is still permitted as part of acid names like "seleninous acid", or "arsorous acid".

Re:Iron Monoxide? (1)

cranky_chemist (1592441) | more than 2 years ago | (#38777593)

According to the IUPAC nomenclature rules (http://www.iupac.org/publications/pac/28/1/0001/pdf/), it is iron(II) oxide.

Has nothing to do with "electric earth" (0)

Anonymous Coward | more than 2 years ago | (#38776403)

The article is genuine and interesting science, but "electric earth" is some kind of bullshit pseudoscience. Not sure why it got into the article headline, since it is completely unrelated. Slashdot embarasses itself in science again...

Re:Has nothing to do with "electric earth" (0)

Anonymous Coward | more than 2 years ago | (#38776467)

No, you're thinking of "electric universe theory".

Was that headline intended to set off the kooks? (1)

John Hasler (414242) | more than 2 years ago | (#38776413)

n/t

Re:Was that headline intended to set off the kooks (1)

Suddenly_Dead (656421) | more than 2 years ago | (#38777275)

I hope so. I haven't seen that Electric Universe guy post in forever. Where's he gone to?

Re:Was that headline intended to set off the kooks (2)

lister king of smeg (2481612) | more than 2 years ago | (#38777587)

The scientology troll ate him

So the takeaway... (2, Interesting)

Anonymous Coward | more than 2 years ago | (#38776453)

is that, conductivity can be induced in compounds that are normally non-conductive, but only at geologic pressures and temperatures.

Is it safe to say, in general then, pressure and temperature play a role for conductivity in all non-conductive 'metal'-based compounds?

Physics Question. (1)

trout007 (975317) | more than 2 years ago | (#38776491)

Is there anyway to tell if the Earth is electrically neutral or has a net charge?

Re:Physics Question. (3, Funny)

Nidi62 (1525137) | more than 2 years ago | (#38776633)

Find a really large sock and see if it stick to the Earth?

Re:Physics Question. (1)

marcosdumay (620877) | more than 2 years ago | (#38778211)

It does. And the smaler ones also do.

Does that mean the Earth is electric?

Re:Physics Question. (0)

UnknownSoldier (67820) | more than 2 years ago | (#38776829)

Uhm, the Earth is effectively a bar magnet moving through space ==> when you move a magnet you create electricity.
Therefore there is untapped free electricity.
QED.

Re:Physics Question. (1, Informative)

Anonymous Coward | more than 2 years ago | (#38776873)

The problem is you need a circuit to tap that "free" electricty. And guess what? That circuit will be a conductor equally moving through space at the same time. Therefore, potential difference = 0. QED.

Why are there SO many scientifically illiterate people on Slashdot? Is it because programming is neither science nor engineering, but depends on both to exist?

Re:Physics Question. (0)

Anonymous Coward | more than 2 years ago | (#38777173)

Why are there SO many scientifically illiterate people on Slashdot?

Because there are so many scientifically illiterate people on Earth?

Re:Physics Question. (0)

Anonymous Coward | more than 2 years ago | (#38776983)

Only if there are surrounding electromagnetically active (ie conductive) materials.

Re:Physics Question. (1)

Hognoxious (631665) | more than 2 years ago | (#38777465)

A brilliant answer. Pity it has nothing to do with the question.

Re:Physics Question. (2)

c++0xFF (1758032) | more than 2 years ago | (#38776959)

One thing we do know is the force from any net charge on the Earth is completely overwhelmed by gravity, the weakest of the fundamental forces. Remember, electromagnetism is about 10^36 times stronger than gravity. This would make detection very hard, indeed, but also suggests that any net charge is very small.

Now, I'm no cosmologist, but my understanding is that current theories require that the universe itself be electrically neutral (but I don't know why this has to be true, personally). So, for the Earth to have any net charge, you have to postulate some mechanism for the charges to get separated by cosmological distances.

Re:Physics Question. (0)

Anonymous Coward | more than 2 years ago | (#38777969)

The universe needs to have a net 0 charge, local spikes in either direction are perfectly acceptable, as long as they cancel one another out.

Re:Physics Question. (2)

ceoyoyo (59147) | more than 2 years ago | (#38777019)

If Earth had any significant net charge you'd stick to it. Really hard. Much harder than gravity pulls you.

Re:Physics Question. (1)

colinrichardday (768814) | more than 2 years ago | (#38777243)

Only if I had a significant charge.

Re:Physics Question. (1)

Hognoxious (631665) | more than 2 years ago | (#38777509)

Doesn't that rest on the assumption that neither you, nor any of your ancestors, nor anything you or they ate, had made electrical contact with the Earth?

Re:Physics Question. (1)

ChrisMaple (607946) | more than 2 years ago | (#38778595)

If Earth had any significant net charge you'd stick to it. Really hard. Much harder than gravity pulls you.

Actually, if the Earth had a significant net charge, everything in electrical contact with the Earth (like you and me) would have close to the same potential. The Earth would repel us, not attract us.

Re:Physics Question. (0)

Anonymous Coward | more than 2 years ago | (#38777987)

Yes, you can tell if the Earth has a net charge. You would quickly see a force on any other charged object, and it would be easy to vary the charge some objects, so you could separate strength of electric force from gravity. Also you can check if the Earth transfers any charge onto something like an electroscope [wikipedia.org] .

repetitive (0)

Anonymous Coward | more than 2 years ago | (#38776565)

isn't it the same story, regurgitated?

http://science.slashdot.org/story/11/12/21/0432222/new-kind-of-metal-theorized-to-be-in-the-earths-lower-mantle

Diamond-Anvil Cell has issues (1)

DingerX (847589) | more than 2 years ago | (#38776757)

My understanding is that the problem with measuring conductivity on materials heated in a diamond-anvil cell is that you have a central spot that is extremely hot, and then a steep temperature gradient to the rest of the material. Measuring conductivity on a diamond-anvil cell often results in simply measuring the circuit formed in these surrounding boundary areas. It's a pity people are still breaking diamonds with these things rather than thinking about the ramifications the test setup has for their measurements.

Communication medium? (2)

zackhugh (127338) | more than 2 years ago | (#38777007)

Satellites are great, but because of the ionosphere, it would be better to send terrestrial messages through the mantle. Can signals be reliably transmitted and received?

Re:Communication medium? (0)

Anonymous Coward | more than 2 years ago | (#38777213)

As far as I remember most conductors are electromagnetic insulators.
So probably no. You could try to use the earth as an antenna though.

Tesla (1)

Anonymous Coward | more than 2 years ago | (#38777077)

In 1895 Tesla was harnessing the electrical conductivity of the earth. From Wikipedia:
A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity of the earth was proposed, in which transmission in various natural media with current that passes between the two points are used to power devices. In a practical wireless energy transmission system using this principle, a high-power ultraviolet beam might be used to form a vertical ionized channel in the air directly above the transmitter-receiver stations. The same concept is used in virtual lightning rods and the electrolaser electroshock weapon,[63] and has been proposed for disabling vehicles.
Edison

Re:Tesla (1)

marcosdumay (620877) | more than 2 years ago | (#38778237)

No. He was conducting electromagnetic waves through the athmosphere. Electric conductivity is a completely diffferent thing.

You can't even have the same material conducting both electromagnetic waves and electricity.

Could explain the _torque_ (2)

mbone (558574) | more than 2 years ago | (#38777149)

The issue is not really the source of the long-period "decade" fluctuations in the length of the day (LOD). It has been known for decades that these have to be caused by "weather" (fluid magnetohydrodynamics) in the liquid outer core. Has to be, as there is no other suitable source of angular momentum. The atmosphere and oceans up here on the surface simply fall short, by as much as an order of magnitude, and nothing else (ice, groundwater, tectonics, etc.) can even match them. The "weather" in the core is dynamically rather different than the weather up here - the heat source is radioactivity and precipitation of solid iron, while the core is quite conductive, and so the dynamics are MHD, not just HD. We don't know much about fluid motions in the core, but we do know that they have to exist, to drive the observed LOD variations (and also drive the observed changes in the geomagnetic field).

What the real question is is the nature of the torque between the mantle and the core. The two leading contenders are pressure torques (differences in pressure across whatever inverse mountains there are at the core mantle boundary) and electromagnetic torques. The E&M torques would be enhanced if the mantle is conducting.

So, this is a plus for the E&M torque theorists, but I wouldn't expect this issue to be really resolved for some centuries, if not longer. The core is not that far away, but it's hard to see through thousands of kilometers of rock...

Re:Could explain the _torque_ (4, Funny)

Hognoxious (631665) | more than 2 years ago | (#38777551)

inverse mountains

Downtains?

what a mover! (0)

Anonymous Coward | more than 2 years ago | (#38777165)

Sounds like spin to me...

Where did you think the electricity went? (4, Funny)

mbstone (457308) | more than 2 years ago | (#38777715)

One side of every electrical circuit is connected to a cold water pipe. And all the cold water pipes are connected to the earth's mantle. This is why there is electricity in the earth's mantle. The solution? Just connect your circuits to an antenna instead of grounding them. This way all the electrons will be radiated into the ionosphere, and you'll once again be able to touch the earth's mantle without getting a nasty shock.

If only there was something condutive that covered (1)

Anonymous Coward | more than 2 years ago | (#38778315)

most of the earth... a fluid that could conduct electricity.... sort of like salt water.

Re:If only there was something condutive that cove (0)

Anonymous Coward | more than 2 years ago | (#38778653)

please get off the site

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