3 ms·

>The definition of "break even" used here (that is, Q>1) is highly technical, and but one factor in the actual "break even" equation. Isn't the Qplasma > 1 the

by floxy 4y ago

>The definition of "break even" used here (that is, Q>1) is highly technical, and but one factor in the actual "break even" equation. Isn't the Qplasma > 1 the most important one here, by a very wide margin? Maybe the only important one at this point in time. That fusion begets more fusion, in a positive-feedback way. That's the breakthrough here. All the other efficiency factors are secondary in nature. That is step 1, and the next step is to scale this up so that eventually Qplasma >> 1. And only then the hand wringing about efficiency of the lasers becomes something to address. It seems like the baby was just born, and people are concerned about which colleges to apply to.

walnutclosefarm 4y ago
NIF achieved plasma combustion over a year ago, as documented in a Nature article earlier this year. If there is a threshold being crossed, that was it. The recent shot tuned that experiment to increase the yield. So now the the total released energy (not capturable, or usable, but released) is greater than the total non-fusion energy captured by the target (not put on the target, but actually captured and turned into useful heating and compression). But that's a completely arbitrary milestone. And, most significantly to me, there is no argument being made anywhere that this milestone is on the path to anything other than a dead end, local optima. That is, that you can further optimized the shape, quality and size of the hohlraum, and shape of the laser pulse to get to a Q that actually has something to do with power generation. (I have no doubt that achieving combustion/ignition is useful for NIF's real purpose, which is to simulate H-bomb physics to aid in maintaining our stockpile of city-destroying weapons - they have in fact created a nano H-bomb).

3 ms·

>The definition of "break even" used here (that is, Q>1) is highly technical, and but one factor in the actual "break even" equation. Isn't the Qplasma > 1 the

by floxy 4y ago

walnutclosefarm 4y ago
NIF achieved plasma combustion over a year ago, as documented in a Nature article earlier this year. If there is a threshold being crossed, that was it. The recent shot tuned that experiment to increase the yield. So now the the total released energy (not capturable, or usable, but released) is greater than the total non-fusion energy captured by the target (not put on the target, but actually captured and turned into useful heating and compression). But that's a completely arbitrary milestone. And, most significantly to me, there is no argument being made anywhere that this milestone is on the path to anything other than a dead end, local optima. That is, that you can further optimized the shape, quality and size of the hohlraum, and shape of the laser pulse to get to a Q that actually has something to do with power generation. (I have no doubt that achieving combustion/ignition is useful for NIF's real purpose, which is to simulate H-bomb physics to aid in maintaining our stockpile of city-destroying weapons - they have in fact created a nano H-bomb).