Hacker News: donquixote25

New comment by donquixote25 in "Lego's 0.002mm specification and its implications for manufacturing (2025)"

donquixote25 — Wed, 11 Mar 2026 22:32:49 +0000

I could be wrong but this article reads like AI. I don't understand why its getting upvotes.

New comment by donquixote25 in "Nuclear physicist explains why fusion ignition is hailed as a major breakthrough"

donquixote25 — Mon, 19 Dec 2022 17:49:09 +0000

I don't think anyone specifically knows. If you ask the physics, they will point to changes (like pulse shape or component sizes) they made due to their increased understanding of the physics. If you ask the target design people, they will point to decrease fill-tube size and number of defects in the capsule. If you ask the facility, they will say their ability increase both power and control power delivery. Likely, it is a combination of everything.

The other point that has been mentioned to me is when you in the self heating regime, there are exponential returns on increasing "quality" of a shot.

New comment by donquixote25 in "Nuclear physicist explains why fusion ignition is hailed as a major breakthrough"

donquixote25 — Mon, 19 Dec 2022 16:59:14 +0000

I mean NIF has spent a majority of its life (11 years) seeing yields below 200 kj. Only in 2021 did it jump above 1 mj and in 2022 above 3 mj. If your definition of breakthrough is rapid improvement, I think this demonstrates it:

See below for previous yields of NIF shots. https://en.wikipedia.org/wiki/National_Ignition_Facility#/me...

New comment by donquixote25 in "Nuclear physicist explains why fusion ignition is hailed as a major breakthrough"

donquixote25 — Mon, 19 Dec 2022 16:55:39 +0000

NIF's definition of Q was defined by the National Academy of Sciences and is analogous to the Q that MCF uses.

New comment by donquixote25 in "Nuclear physicist explains why fusion ignition is hailed as a major breakthrough"

donquixote25 — Mon, 19 Dec 2022 16:48:46 +0000

The definition of Q that is being used was established by the National Academy of Sciences not NIF.

NIF previously tied to use the hot spot energy instead of target energy in 2013, which they were criticized for, and rightfully so. But this definition of Q is analogous to the definition of Q used by MCF.

New comment by donquixote25 in "US Department of Energy: Fusion Ignition Achieved"

donquixote25 — Tue, 13 Dec 2022 20:49:47 +0000

Law goes into effect next year.

New comment by donquixote25 in "US Department of Energy: Fusion Ignition Achieved"

donquixote25 — Tue, 13 Dec 2022 18:46:56 +0000

No, this is ignition. However, the reason why this is a big deal is because it is scientific break-even.

The first time they achieved ignition was in August of 2021. See paper below:

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12...

New comment by donquixote25 in "Secretary Granholm to announce major scientific breakthrough by DOE [video]"

donquixote25 — Tue, 13 Dec 2022 18:25:46 +0000

What is your point? That we should distrust everything in a scientific journal? You are shifting the goal post. First, you wanted a publication. Now, you say that would not be enough?

I am inclined to believe a publication unless other plasma physicist come out with a contradictory information.

It's easy to be cynic...

New comment by donquixote25 in "Secretary Granholm to announce major scientific breakthrough by DOE [video]"

donquixote25 — Tue, 13 Dec 2022 17:08:54 +0000

If you were familiar with NIF, you would know that they absolutely will publish the details of the experiment just as they published the details of the experiment that achieved ignition in August 2021: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12...

New comment by donquixote25 in "Secretary Granholm to announce major scientific breakthrough by DOE [video]"

donquixote25 — Tue, 13 Dec 2022 15:32:25 +0000

The laser energy is converted to x-rays by the gold cylinder. But the cylinder only has a conversion ratio of 10~20 percent, so the amount of energy that gets deposited on the capsule is much lower.

New comment by donquixote25 in "Secretary Granholm to announce major scientific breakthrough by DOE [video]"

donquixote25 — Tue, 13 Dec 2022 15:30:37 +0000

It's amazing how people even in hacker news just say whatever they want with absolute certainty.

This is ignition but ignition was achieved by their August 2021 shot. See this paper for the details: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12...

The reason why it's a big deal is because they surpassed scientific breakeven.

New comment by donquixote25 in "Fusion energy breakthrough by Livermore Lab"

donquixote25 — Tue, 13 Dec 2022 04:33:44 +0000

That is only true to a certain point. Look up Paschen's law. After you go lower than a certain point, around 10 Torr cm depending on the gas, decreasing pressure increases the breakdown voltage.

It's probably not feasible to pump to such low pressures in wind turbines, so they probably don't even try. But for NIF, it's common.

New comment by donquixote25 in "Fusion energy breakthrough by Livermore Lab"

donquixote25 — Tue, 13 Dec 2022 01:00:27 +0000

Yea, the whole target bay is in vacuum which helps with the arcing.

New comment by donquixote25 in "Fusion energy breakthrough by Livermore Lab"

donquixote25 — Tue, 13 Dec 2022 00:19:40 +0000

Sure we can wait, but there already has been publications about the August 2021 shot, in which they determined that the August 2021 met the ignition criteria. It's pretty clear that they were on the verge of achieving scientific break-even.

Maybe we are just arguing about semantics and what constitutes a breakthrough but in my mind, the hardest challenge of fusion has been getting scientific gain over 1. There are still OTHER hard problem like continuous operation, capturing energy, but ultimately, getting scientific gain over 1 is/was the most challenging. You can say it isn't but the fact is, none of the MCF concepts have achieved a scientific gain over ~.64 and have not improved since the 1990s (JET). Look, if the 7-X or ITER or JET achieves a similar scientific gain, they will get similarly applauded.

I'm not saying that fusion will become a economically viable power source now. It is just that NIF de-risked the hardest challenge of fusion from a pure physics standpoint: more energy out than in.

New comment by donquixote25 in "Fusion energy breakthrough by Livermore Lab"

donquixote25 — Mon, 12 Dec 2022 22:52:09 +0000

Many fusion new articles have this problem but i would argue that this time, how FT categorized this is appropriate. This is literally the first time the scientific break-even (not engineering break-even) has been achieved by any controlled experiment, including MCF. How is that not a breakthrough?

New comment by donquixote25 in "Success in Canada means moving to America"

donquixote25 — Sat, 14 May 2022 17:15:39 +0000

Dylan was not insisting that every culture must be a mixture of foreign culture. He is just generalizing that multiple cultures is better than one. By the way, on aggregate, America is a melting pot of different cultures and has dominated popular culture the past couple of decades.

Also, he says he came from a small town so I don't think it is fair to characterize him as a coastal elite.

New comment by donquixote25 in "Apple’s profit is always the priority–no matter the cost"

donquixote25 — Thu, 10 Feb 2022 00:05:44 +0000

That's true. I guess if all the app developers pulled their apps out of the app store, the larger companies could just come in with their own version of all the apps.

New comment by donquixote25 in "Apple’s profit is always the priority–no matter the cost"

donquixote25 — Wed, 09 Feb 2022 20:28:21 +0000

None those will ever happen unless developers/app companies for a union of some sort.

New comment by donquixote25 in "The Kelly criterion: How to size bets (2019)"

donquixote25 — Wed, 09 Feb 2022 01:15:16 +0000

If you knew you had a 60% chance of winning, wouldn't you want to bet a small amount to reduce variance?

I guess on the down side that is A LOT of clicking. It is similar to how when playing a better team in basketball, you want to slow down the pace of the game to limit possessions.

New comment by donquixote25 in "Skydio: $1k Skydio 2 drone launch takes aim at DJI"

donquixote25 — Sun, 06 Oct 2019 17:19:14 +0000

Hi! Joining the party late, but why did you guys opt for the two propellers up/two propellers down design?