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I'm a physics layman, and I'm having some trouble with uniting the content of your comment with the fact that existing magnetic confinement experiments have reported maintaining a plasma at the right temperature for longer times (not with fusion, but with microwave heating, and with the power of those heaters in the 10MW range).

Have I understood the consequences of those reports wrong? Does the heat loss you talk about only occur with fusion? (And if so, is it even a problem if the conditions for fusion to occur can be created by external heating this "easily"?)


In order to protect astronauts from decompression, the hull of a spacecraft has to be insanely good at stopping gas particles. Not 99.5% good, but like 99.9999999…% with 20 zeros! That’s very good.

But a thin metal sheet has no trouble doing this, as demonstrated by the Apollo lunar lander.

Some things are just not as hard as they sound. Magnetic confinement works very well. It easily achieves the necessary 9’s.

It’s just hard to keep it stable at millions of degrees, but that’s a different problem.


Wait til you guys hear about DNA transcription error rates!


Are you saying the way to contain plasma is the shape of a double helix


*Slaps proton*

These things can fit so many nines of reliability.


I'm not sure, but we can try to figure out what is going on. And by the way I'm a physics layman too. I just read a lot of books about fission and a few about fusion too, it happens to be my hobby. When I'm bored, the bookmarks that I browse are [1] and [2].

So, when reports state that the a certain temperature was achieved and sustained for a certain period of time, what are they actually saying? We could go and find an article and get into some details, but I imagine they say that somewhere in the plasma that temperature was reached and sustained. But it is quite likely that that region is quite microscopic, maybe a very, very thin inner torus inside a larger torus. There is a gradient of temperature from the region where the announced temperature happens to the walls of the device. But one way or another that thin inner region can't have a surface area of anything close to 1 square meter. To get to 1 GW of power, you need 10^-12 square meters, and to get to 10 MW you need 10^-14 m2. That's about the surface area of a torus of (circular) length 3 m and diameter 1 femtometer. 1 femtometer is roughly the size of a nucleus of deuterium or tritium, so in principle this is the minimum diameter of a torus where you can talk about fusion.

[1] https://www.ncnr.nist.gov/resources/n-lengths/

[2] https://www.oecd-nea.org/janisweb/


I'll assume the inlet is below water level / at the bottom of the tank…


I suppose assthetics is in the eye of the beeholder?


Argh, using this would cause name collisions in my brain. https://github.com/agersant/polaris/ ^^


Guess my IoT devices will have to learn how to watch videos.


That's what I was thinking :)


At 75 MB/s, this thing takes 30 days to fill. How much slower would you like?


Who says we need to fill it up in a reasonable time frame? If each disk costs a comparable amount to a dvd (cents) then the expensive part is the electricity (and maybe the equipment to write to them) and it's ok if most of the theoretical storage capacity goes unused. The important metric here for something like data backup is cost/byte to write and cost/byte/month to maintain.


> Who says we need to fill it up in a reasonable time frame?

So you yourself are saying anything longer than a month is unreasonable?

In any case, this lab experiment will need much improvement in speed and energy requirements.


No, I'm suggesting that it could take a decade and still given the numbers in the thread I replied to (which I agree appear not to reflect reality) be a viable product. It never needs to be 'full'.


A few years maybe? The point of large storage mediums is rarely to fill them up as quickly as possible; rather the opposite.


The hitch guide to the solar system


Well, if you're playing with wasm like this post, you could sidestep canvas and render the image on the wasm side. c.f. https://github.com/plotters-rs/plotters-wasm-demo


My monitor doesn't have dcc. I've worked around that part by activating automatic input selection and xset dpms force off'ing on the device I want to switch away from.


Can anyone compare this to https://radicle.xyz/? (Or am I wrong thinking they're similar? I've used neither.)

I suppose gitstr would have the benefit that you'd already have the public key of whatever person you'd want to send the patches to? Because you learned of the existence of their repos via nostr, or so?


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