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Egyptians did it 5000 years ago. Isn't it the time for a remake of the
Pyramids? If we match the effort and investment on the old ones,
with our technology we should be able to make one that is 100
miles across! That would give a peak that is 50 miles above ocean.
Almost space!
It can
be located somewhere between Arizona, Nevada, and Mojave
desert. If we get 100,000 non-unions to work on it with 10,000
trucks and cranes etc., working from several quarries, my
guesstimate is it should be complete in 10 years.
Why, if someone can suggest a steel tunnel 400 miles long (800
miles roundtrip), can I not suggest this crazy idea? You can
paraglide down from it to Salt Lake City, Las Vegas, Portland, San
Francisco, or even L.A.!
Okay, let's get to a more Futuristic version of the Pyramids. This one
is made of Superconductor Magnet rings. The very bottom ring has
a D of 100 miles, next one, 50 miles, next one 25 miles, etc. Each is
like 100 ft. thick in cross-section. Load them each up with 100
MegaAmps, with alternating current direction between each layer.
They should all shoot to the sky and reach as far as 100 miles high!
Make an elevator in between them, and you have your Space Hotel!
I wonder how many of those who blame me for criticising me for
criticising a crazy idea will criticise me now.
Spaceframe_20Mountain
[FlyingToaster, Aug 29 2013]
Desert_20Space-Scraping_20Arcologies
[FlyingToaster, Aug 29 2013]
Space%20Mountain
[FlyingToaster, Aug 29 2013]
StarTram
http://www.startram.com/
This was where I got the original idea. BUT, they do not talk about stacking the magnets like I do. [xkuntay, Aug 29 2013]
Force and field between two wires
http://hyperphysics...agnetic/wirfor.html
Calculate by plugging in the numbers. [xkuntay, Sep 01 2013]
[link]
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Superconductor No. Individual platform weight (per m): 50 kg Cable weight (per m): 0.1 kg
Decrements for platform length: 10 m Assuming repulsion only between adjacent platforms.
Force between two wires 7MAmps each, 5000m apart: 1959 N/m Force between two wires 7MAmps each, 10000m apart: 979 N/m
Platform no. height(km) Platform length (m) total weight (kg) weight (kg/m) force (N/m)
1 5 49955 85425300 1710.045041 16758.4414
2 10 48965 82927050 1693.598489 16597.26519
3 15 47985 |
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//I wonder how many of those who blame me for criticising me for criticising a crazy idea will criticise me now.// |
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If that sentence means what I think it means, then there's always <link>, <link> or <link>. |
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Good finds. Have not seen anything with superconductor magnets though. |
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Also, criticise is acceptable. |
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if you want to put something into orbit you want to do it horizontally, not vertically, so along the top ridgeline as posited in the first link (my idea, marked as mfd because it's redundant with the second link, Vernon's idea). Regardless of which, specifying "superconducting magnets" seems rather non-sequitur, given the magnitude of the idea. |
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Come again? I do not intend to launch things to space. This is just for people to go up the elevator, spend a night at the top ring, and come down. |
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This is doable with current technology, and could even be feasible. Maybe only $2 billion. Not much for Muskee. |
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I have another device to launch things to space. That comes next. |
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with bated breath I await. |
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I'm thinking about baiting my breath, if I have to keep reading these. |
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My breath comes pre-bated, I have a small 3D printer that does it. |
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Or you could remove that bit about mexicans, wasn't funny. |
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Try category : Public : Architecture or something other than General!! |
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oh, you mean the thing will be built from magnetic repulsion. nifty. |
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But I'm gonna guess the amount of magnetic force necessary to repulse the elements on the order of 10's of miles against gravity is going to |
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a) require more electrical power than the human race currently produces, and |
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b) do incredibly nasty things to passengers. |
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You are right on b). well, unless they leave all their metal things
behind.
Not on a). that is why they are superconductors. Once you load
them up they will stay with minimal energy. |
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Completing them in ten years isn't anywhere near the
same level of effort. Whole cities were dependent on
the building of the pyramids over hundreds
(thousands?) of years.
If we were to exert the same effort today we could
pretty much pick any project from science fiction
and see it done. Or just reshape the moon into a
pyramid. |
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// how many of those who blame me for criticising
me for criticising a crazy idea will criticise me
now.// |
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Okay. Where are your clever rear remarks? No rebuttals? |
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Give me a chance, bud. I haven't even begun the
buttals yet. |
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In the meantime: "build a big pyramid" - meh. Not
much point in posting an idea simply to have a rant,
but I guess it's been done before. |
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Now, a Sierpinski Triangle Pyramid, there you'd have something. And it wouldn't cost anything in tems of materials, since the surface area would be zero. Manpower and tooling might be more of an issue. |
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Again, please note that this pyramid is made up of superconductor magnets that repel each other. Basically, you have a floor every 5 miles and nothing in between. It works with levitation. |
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I do not know what the highest levitation achieved to date is, but theoretically if the superconductor magnet is strong enough you can repel an iron block up to 5 miles high. Same applies to two magnets with opposite polarities. |
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Now continue the pattern. First floot with N-S, next one with S-N, then N-S again, and all are fixed with Meissner effect. If you do a cascading with smaller magnets every floor, you can theoretically go up to 50 to 100 miles, with 10-20 magnet "rings". This structure will float in the air, will have minimal air drag on it, which can be countered with fans on each floor, and will be strong enough to support small equipment. If I had 20k to spend, I would do a miniature one of 10 ft high and it would I bet be a great showcase. |
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Yep, this would work on one of the planets. Just not
this one, 'cos last time I saw, Superconductors need
liquid Nitrogen. |
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Not like they are using nitrogen as fuel. They will have on board
coolers. There are palm sized devices that make liquid N. How
else do hospitals use them.. Maglev... Power lines.. Duh? |
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Palm sized devices for making liquid Nitrogen? I know of
the molecular sieve process which produces Nitrogen gas,
but liquid Nitrogen from a palm sized device must be
deviously clever. |
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Well you cant make a substance obviously but you can extract it
from air. Chill air to -195 degrees C. Oxy condenses first. Take
away the liquid. Then chill further to -200. That should give 90%
liquid nitro. Not that you need it for this topic. |
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Well, I looked at one Company's web site, and they
have something the size of a small water dispenser
that produces about a litre per day with the power
consumption of a normal freezer. |
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Perfect Halfbaking material... |
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Anyway, Professor FJ Lewis, returning to the subject... |
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// I do not know what the highest levitation
achieved to date is, but theoretically if the
superconductor magnet is strong enough you can
repel an iron block up to 5 miles high. Same applies to
two magnets with opposite polarities.// |
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That just sounds...incredible. First, with a steady state
field, I never saw iron do any repelling...am I
mistaken? But *like* poles repel, or at least, currents
in opposite directions repel. |
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But 5 miles?
I'm going to try to think out loud:
Critical current density is one limiting factor.
Current in the Superconductor is proportional to it's
cross section.
Separating force per unit length is proportional to the
square of the current, and inversely proportional to the
distance (assume 2 identical conductors, and
assuming the conductor is represented by a zero
thickness line).
But per unit length weight is proportional to the area
as well.
Since the conductor has thickness, the further parts
do not generate the same separation force as the
nearest parts.
So, a bigger superconductor would not levitate more
than a small one? |
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Good points. A bun for you for that. I don't know who Prof. Lewis is, but I am sure he is smart. |
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Let's start with iron levitation. Youtube levitation. That's that. |
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I initially thought the Critical Current Density could be the limiting factor. Well, guess what? You can make the cross-section of the superconductor as large as you want (or strand several hundred wires together) and you can get 7 MAmps without exceeding CCD. |
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Now, go to [link] and plug in 7 MAmps for two wires that are 5000 m apart (okay, 3.0 miles). |
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Gives you 1959 Newtons per m. That is about 195 kg per m. If your superconductor is ligher than that, you have a lift. |
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Now, the problem is Critical Field. But use the same website address to calculate magnetic field at 1m for 7 MAmps. Turns out only 1.46 Teslas. Most superconductors easily handle 2-3 Teslas. |
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Am I missing anything? I am also curious. |
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Well, if I search for iron levitation, mostly I get trailers
for Iron Man 3. But levitation is not the same as
repulsion, and although Iron levitation is quite
common using an overhead electromagnet, I have
never seen iron repulsion. Can you post a link? I would
like to see this. |
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For the 7MA superconductor: if critical current density
is 100KA, then a 70m2 conductor is required. If its
density is only around 3t per m3, it will weigh 210t/m
of conductor. But separation force is about 2000N/
m...enough to lift 0.2t. I think that is what you are
missing. |
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By the way "F J Lewis": search "History today" on
youtube. |
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Well that assumption will be wrong. CCD is not that low for most
SC. They successfully pushed 100kA through a 1mm thick wire.
So, we are looking at 0.2 m2 crossection of wire. The rest can be
a very light composite foam. With your density, it could still be
too heavy. Then what do we do? |
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Well, then you bring them closer, to 1 mile. They have to
balance somewhere. Every time you reduce distance by half, you
quadruple the force. |
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Call it what you like, but there is a pic of an iron block floating
on SC in wiki (okay it was a ferromagnet, not pure iron).
itcomes back. |
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Also, I think a 10 mile long cable is going to apply more force
than a 1 mile cable. Not 10 times more, but 4 - 5 times. That is
why it is a pyramid. |
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