Science-based what-if questions

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andykhang
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Re: Science-based what-if questions

Postby andykhang » Mon Jan 09, 2017 10:53 am UTC

...So what type would work the best?

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Eebster the Great
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Re: Science-based what-if questions

Postby Eebster the Great » Tue Jan 10, 2017 9:15 am UTC

gmalivuk wrote:No, it doesn't make any difference. No amount of simple lenses can do what you want.

It's not that "no amount of lenses" can do it, because the Sun is certainly hot enough, it's that the total area of such lenses must be gigantic.

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Re: Science-based what-if questions

Postby gmalivuk » Tue Jan 10, 2017 1:45 pm UTC

How many lenses will get you a death beam?
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Re: Science-based what-if questions

Postby Copper Bezel » Tue Jan 10, 2017 2:15 pm UTC

I don't understand andykhang's original question - the nanomachines are driving water droplets in the air around, and that's what's making up the lenses? But a death beam with a defined diameter is collimated.
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Flumble
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Re: Science-based what-if questions

Postby Flumble » Tue Jan 10, 2017 2:25 pm UTC

gmalivuk wrote:How many lenses will get you a death beam?
fifty-twelve

At what point can a collection of focal points be considered a 'beam'? If we go for a 5cm spacing between all focal points, you only need some billions of lenses for a 70cm wide 'beam' from high in the sky down to the ground. And a multitude of that in water droplets.

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Eebster the Great
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Re: Science-based what-if questions

Postby Eebster the Great » Tue Jan 10, 2017 5:10 pm UTC

More than a few it seems. But "billions" is not necessarily deal-breaking for nanobots. I feel like you might be underestimating the requirement a little.

KittenKaboodle
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Re: Science-based what-if questions

Postby KittenKaboodle » Wed Jan 11, 2017 3:05 am UTC

gmalivuk wrote:No, it doesn't make any difference. No amount of simple lenses can do what you want.

While the OP perhaps did imply using the water droplets as lenses, since they have "absurd amount of [magical] nanomachines" I think we can do better than "simple" and while the word "beam" is problematic, they did say "converge" and I'm not so sure "beam" nesicarilly means it is collimated.

If (and don't forget we are using magic here) we use reflection rather than refraction an assuming we know the position of our target in three dimensions (allowing using a conical "beam"): http://web.mit.edu/2.009/www/experiments/deathray/10_ArchimedesResult.html and https://www.youtube.com/watch?v=bEvbj3O_yt8

edit: well, of course, refraction can work too: https://www.youtube.com/watch?v=i_8cynWnAw8 and a Fresnel is something one might be able to make with water drops (and magic)

morriswalters
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Re: 10 kg of antimatter

Postby morriswalters » Wed Jan 11, 2017 3:40 am UTC

andykhang wrote:What happen if you put 10 kg of antimatter into the core of the earth:

1. Through a straight, vacuumed hole into the center?

2. Instantly through a 1 way portal?

And what would you do, personally, to destroy the earth with the above?
If we are dealing with magic then travel through your one way portal to the asteroid belt and get some rock moving towards earth. Like Ceres. If if space travel is too much take some to each super volcano on the ring of fire and try to set them off. You might get lucky. I like the nanobots. Make seven billion, give each a little antimatter and have them enter the bodies of all humans and use it to blow the aorta. No collateral damage to the planet.

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Re: 10 kg of antimatter

Postby p1t1o » Wed Jan 11, 2017 10:45 am UTC

morriswalters wrote:
andykhang wrote:What happen if you put 10 kg of antimatter into the core of the earth:

1. Through a straight, vacuumed hole into the center?

2. Instantly through a 1 way portal?

And what would you do, personally, to destroy the earth with the above?
If we are dealing with magic then travel through your one way portal to the asteroid belt and get some rock moving towards earth. Like Ceres. If if space travel is too much take some to each super volcano on the ring of fire and try to set them off. You might get lucky. I like the nanobots. Make seven billion, give each a little antimatter and have them enter the bodies of all humans and use it to blow the aorta. No collateral damage to the planet.


Just for fun:

10kg / 7e9 = 1.43micrograms

Annihilate 2.86ug of matter+antimatter liberates = 2.57e8 J

1ton TNT equivalent = 4.184e9 J

Blow the aorta? Each person would have the equivalent of ~60kg of TNT allocated. No need to worry about specific bodyparts.

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Re: 10 kg of antimatter

Postby Soupspoon » Wed Jan 11, 2017 11:02 am UTC

p1t1o wrote:Blow the aorta? Each person would have the equivalent of ~60kg of TNT allocated. No need to worry about specific bodyparts.
Surely, though, if you were going to be indiscriminately killed off by a maniacal genius, you'd appreciate such a normally insignificant detail being arranged 'just so'... It shows that they do care. After a fashion.

p1t1o
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Re: 10 kg of antimatter

Postby p1t1o » Wed Jan 11, 2017 12:00 pm UTC

Soupspoon wrote:
p1t1o wrote:Blow the aorta? Each person would have the equivalent of ~60kg of TNT allocated. No need to worry about specific bodyparts.
Surely, though, if you were going to be indiscriminately killed off by a maniacal genius, you'd appreciate such a normally insignificant detail being arranged 'just so'... It shows that they do care. After a fashion.


Its true, I didnt take into account "wow" factor!


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