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Comment Mathematicians do the exact same thing (Score 1) 211

In stories, we're happy to accept totally absurd giant robots, but unhappy about magical bridges that don't snap back and fall. It's the same in math. If you don't like the backdrop, then you go down a couple dimensions or switch to a simpler manifold or consider the simpler homomorphic structure that preserves the property you want. But make a conclusion about the wrong side of a quadrilateral and your colleagues might throw pencils at you. We are preserving the things that are important to achieve a correct model.

Comment food growing to scale (Score 1) 134

I just want to say, most people have no idea how many plants one must grow in order to survive. If you, 1 adult, want to get most of your calories from a plant, a potato is a decent choice. You can plant 5 kilos of potatoes in a 30 meter row, and expect ~ 90,000 kC. Since they take 90-120 days to mature, in order to have a continuous supply, you'd want maybe twice this many, along with lots of other plants that supply calories, protein, vitamins, and flavor. Two rows of potatoes are about a meter wide, so you're looking at 30-40 m^2. You have to dedicate about 1/25 of your potato crop to seeds, and have a good place to store them. This is also assuming that you are great at growing potatoes, nothing goes wrong, and you plant them every week and harvest them every day.

Due to low light on Mars, you might divide this yield in two. Probably the way it would go is the initial harvests would be smaller until you figured out which varieties yielded more. I'd want 80 m^2 just for potatoes, per person. Then there's all of the other plants. I'd plan on having a 250 m^2 facility, per person, at least.

Comment Use the moon for all launches (Score 2) 151

It would be ideal to use the moon as a platform for all satellite launches, supposing we can find the raw materials there to make metals. There's enough water and oxygen for humans, and enough silicon to make photovoltaics. Electronics and rare or hard-to-purify materials could be imported from Earth. Fuel could be made using the PVs by reduction of water or other reactions. Once we have a good lunar base, putting satellites in orbit around the Earth or sending ships to Mars will be far more efficient and less polluting and wasteful. And we could use toxic or radioactive rockets that we can't launch from Earth, with fluorine as an oxidizer, or fission.

Comment Like a cathode screen (Score 1) 30

The best reason that I can imagine for this occuring, is that the clouds can act as a giant cathode screen. Inside of a vacuum tube, you have a lot of volts on an anode, and there's a nearby cathode that the electrons are attracted towards. But at the cathode, instead of just being a plate, there is a fine screen or mesh. Then the electrons try to hit the cathode, but some of them pass it and continue on in the direction they were accelerated in. in the case with clouds, several large charges are attracted upwards towards a charge sink, and a conductive plasma column (lightning) forms and carries most of the electrons into the sink, but some of the adjacent electrons miss or are too late, and are instead accelerated into the thinner upper atmosphere, and there they ionize oxygen and cause these ephemeral flashes.
Just an idea.

Comment Re:There is no reason for any drought to continue (Score 1) 390

I came to say this as well, and add some personal experience. I grew up in Lancaster, and area called the Antelope Valley in the Mojave Desert, the high desert area halfway between LA and Bakersfield. When my grandpa was a boy, in the 1930's, the water table was between 3 and 30 feet underground. The area was excellent for alfalfa production, and farmers sucked up all of the groundwater, while simultaneously LA redirected streams in the mountains, that fed the aquifer, into their water supply. There are photographs from the 30's showing the region as arid, but black locust trees grew everywhere. Now the water table is below 2000 feet underground, and the region hardly supports desert scrub. There's one small hole in the ground, that if you drop a rock down, it rings thunderously for 10-20 seconds. And there's no more farming in the Antelope Valley, of course.

A huge el niño is forming, and there's going to be some relief, but the next time this happens, the rest of the state is going to be just like the Antelope Valley, because the legislature is doing nothing to fix the problem. Using up the groundwater changes the ecology, and it is really disheartening, because California is being ruined by these practices.

Comment Re:Nobody will notice or care, outside of the regi (Score 1) 265

This is according to an expert on earthquakes:

About 10% of great earthquakes trigger a volcanic eruption, and most eruptions are fairly minor, so the volcano risk is small compared to the earthquake risk.

I live in Olympia, and I like to say that when the big one hits, Mt. Ranier is going to blow, and as the black lightning-filled clouds tower over us in the east, all of the metal bands in town will climb onto the roofs of all of the buildings with all of their equipment and it will be the most Metal day ever. But it looks like experts believe otherwise. https://www.reddit.com/r/IAmA/...

Life. Don't talk to me about life. - Marvin the Paranoid Anroid