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How to destroy the Earth (2006)

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Re: How to destroy the Earth (2006)

#31

Post by ars »

Arnavion wrote: post #26
ars wrote: post #23

Here's my way: An enormous particle accelerator. Shoot electrons into space in vast quantities until the whole earth becomes so highly charged it blows itself to pieces.

Shooting electrons out gets harder and harder as you go since you're counteracting an ever increasing positive charge from the Earth. Besides, on a uniformly conductive sphere (which admittedly the Earth is not at the crust but probably is near the mantle and core), excess charge distributes over the surface, so only the top layer of the Earth would get blown off (along with your accelerator).

> Shooting electrons out gets harder and harder as you go since you're counteracting an ever increasing positive charge from the Earth.

Sure. This is fantasy of course - my accelerator is powerful enough to handle it.

> excess charge distributes over the surface

Yes. The plan is to put the accelerator in a hole so it can tap into all the electrons that are hiding below the surface (since the surface would be depleted of electrons). As the surface is blown away it would dig itself deeper.

It wouldn't blow itself to pieces like a bomb in a move, but rather as giant chunks fling themself into space chasing the electrons I've shot there.

I like my plan because I think it's the most energy efficient one out there that is actually theoretically possible today (i.e. doesn't require new physics).

Re: How to destroy the Earth (2006)

#32

Post by teraflop »

ars wrote: post #24
logfromblammo wrote: post #22

I choose a "meticulously deconstructed" variant. I call it the "onion method". First, invent a self-replicating robot. It does not need to be miniaturized. It would actually probably work better if they were all stadium-sized. Allow replication, using solar energy and near-surface resources, until the entire planet is covered by a uniform layer one robot deep. The robots then securely connect to their nearest neighbo…

Solar wind is not strong enough to put something in orbit.

I dunno. Given a self-supporting spherical structure around the planet, you could raise it above the atmosphere and set it up to experience a net torque from solar radiation pressure. Just add "sails" that are black on one side and mirrored on the other. Then sit back as it very very slowly spins itself up to orbital velocity.

Of course, there would be plenty of practical difficulties. (For one thing, radiation pressure is a hideously inefficient use of energy; for another, your spherical shells will be unstable and require constant maneuvering to keep them centered.) So if you have an army of self-replicating robots, it's probably easier to just have them build millions of solar-powered mass drivers and fire rocks directly into space.

Re: How to destroy the Earth (2006)

#33

Post by mikeash »

TeMPOraL wrote: post #14
ck2 wrote: post #2

This comes up on HN every year but I re-read it every time. My idea is just figure out a way to nudge earth towards the sun and inertia will do the rest, slowly but surely, so a vote for their #10 Or settle for wiping out all human life on earth and earth will survive just fine without us. Picking a US President that will use nuclear weapons might be a dangerous starting point to investigate.

> Or settle for wiping out all human life on earth and earth will survive just fine without us. Picking a US President that will use nuclear weapons might be a dangerous starting point to investigate. This may be very dangerous. When you take antibiotics, you need to do the full course, 'lest some bacteria survive. Similarly, if the nuclear destruction isn't complete enough, the surviving humans will repopulate the p…

That's an excellent point. If you think humans are bad, nuclear-resistant humans are worse.

Re: How to destroy the Earth (2006)

#34

Post by derekp7 »

sevenless wrote: post #30
zeveb wrote: post #6

This reminds me of what the Web used to be: amusing entries by interesting people, devoid of advertising, marketing or JavaScript.

In the same vein I've got to recommend * Norman Yavin's Usenet archive of interesting technical and science related posts ( http://yarchive.net/ ) * Prof James Calvert's pages on about everything worth knowing ( http://mysite.du.edu/~jcalvert/ )

Prof Calvert's page reminds me of John Savard's home page: http://www.quadibloc.com/ -- I ran across this back when I first got into slide rules, but there is a lot of other good stuff there too.

Re: How to destroy the Earth (2006)

#35

Post by deciplex »

TeMPOraL wrote: post #17
wlesieutre wrote: post #5

Earlier quoted context omitted.

> My idea is just figure out a way to nudge earth towards the sun and inertia will do the rest, slowly but surely, so a vote for their #10 I don't think you can. Even if you could give the whole Earth a push toward the sun, it has enough orbital velocity (~30,000 m/sec) that it'll miss and keep on going around. You might turn its orbit into a slightly different ellipse. Say we want to straight up (down?) launch a pro…

> You could potentially dump some energy with a gravitational assist off of Venus (transfer some of our momentum into speeding up its orbit while slowing ours down) I've heard that a hard turn around Jupiter is even better. I remember Scott Manley dropping a probe into Kerbol via Jool gravity assist in one video[0]. Actually, now I want to make a simulation with Earth doing Jupiter flybys. What's good for that nowada…

Scott Manley also made a trip to Minmus using only the starting Career parts. Just because he did a thing doesn't mean it's the optimal way to do that thing :-)

(In fact, it's probably a better indicator against, heh.)

Re: How to destroy the Earth (2006)

#37

Post by deciplex »

_kst_ wrote: post #12

Method 1: Annihilated by an equivalent quantity of antimatter I don't think this would work as well as one might assume. When Earth and anti-Earth collide, the vast majority of the mass will be blown into space by the initial explosion, and will never actually get a chance to annihilate. There might even be some coherent chunks left over. If you can manage to transform every other atom from matter to antimatter, even…

> I don't think this would work as well as one might assume. When Earth and anti-Earth collide, the vast majority of the mass will be blown into space by the initial explosion, and will never actually get a chance to annihilate. There might even be some coherent chunks left over.

The author mentioned an Earth made from antimatter. How about a spherical shell of gaseous antimatter, whose total mass is equal to Earth? Make Earth the center of this sphere, then wait.

Re: How to destroy the Earth (2006)

#38

Post by dkbrk »

> Antimatter... it may be possible to find or scrape together an approximately Earth-sized chunk of rock and simply to "flip" it all through a fourth spacial dimension, turning it all to antimatter at once.

Obviously this idea is entirely speculative, but I haven't heard of it before and was wondering what the theoretical foundation for it is.

I think it's alluding to a 4D rotation causing a change in parity, which seems plausible. Physics is very nearly symmetric under a conjugation of parity and charge (the CP symmetry, which is violated only by the weak nuclear force); so the idea would be that a change in parity through this 4D rotation causes a charge conjugation, maintaining CP symmetry.

I don't think this would work. Symmetries in Physics imply a conserved quantity, through Noether's theorem. The problem is that the conserved quantity associated with a charge-conjugation symmetry is not charge itself, but 'charge parity', a multiplicative quantum number. Under CP-symmetry, the product 'charge parity' * 'spatial parity' is the conserved quantity, so a change in spatial parity from the 4D rotation would cause an associated change in charge parity (assuming CP symmetry), which merely means the system would behave differently under a charge conjugation operation, not that the charge is actually changed.

Charge conservation itself originates from the gauge invariance of electromagnetism, and I'm not sure how that would be affected by this scenario.

I'm not saying the idea is necessarily wrong, but I think it's likely to have originated from a misunderstading.

For further information:

- https://en.wikipedia.org/wiki/Symmetry_%28physics%29#Conserv...

Re: How to destroy the Earth (2006)

#39

Post by vinceguidry »

ck2 wrote: post #2

This comes up on HN every year but I re-read it every time. My idea is just figure out a way to nudge earth towards the sun and inertia will do the rest, slowly but surely, so a vote for their #10 Or settle for wiping out all human life on earth and earth will survive just fine without us. Picking a US President that will use nuclear weapons might be a dangerous starting point to investigate.

Small amounts of force applied in any direction will not set the Earth into a collision course with the Sun. An intuitive explanation for why can be found in the game Osmos.

www.osmos-game.com

The short reason is that inertia is the entire reason the Earth is orbiting the Sun right now, you have to overcome that inertia rather than generate more of it. When you're playing Osmos during the orbital sections, a little bit of playing around reveals that the best way to reduce your orbit is to thrust in the same direction you're currently moving in. To increase your orbit, you thrust in the opposite direction. Thrusting towards or away from the 'star' alters your orbit somewhat but doesn't really change how far away from the star you are on average.

After awhile you figure out the right way to finesse your way into orbits that carry you on a trajectory to eat smaller bodies. With that skill comes the dying off of the fantasy of being able to easily dispatch the Earth in this fashion. Inertia doesn't work that way.

Re: How to destroy the Earth (2006)

#40

Post by [deleted] »

derekp7 wrote: post #34
sevenless wrote: post #30

Earlier quoted context omitted.

In the same vein I've got to recommend * Norman Yavin's Usenet archive of interesting technical and science related posts ( http://yarchive.net/ ) * Prof James Calvert's pages on about everything worth knowing ( http://mysite.du.edu/~jcalvert/ )

Prof Calvert's page reminds me of John Savard's home page: http://www.quadibloc.com/ -- I ran across this back when I first got into slide rules, but there is a lot of other good stuff there too.

[deleted]
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