Reply To: $40million raised for boron fusion

[jamesr]

Sorry, I didn’t mean to be flippant (I had just come back from the Pub when I posted it).

I assume you are suggesting if a pellet of fuel is inserted into the point where the colliding filaments normally form the focus. Whether the pellet is room temperature, frozen at a few Kelvin, or cooled further to near absolute zero to make a Bose Einstein condensate wouldn’t make much difference. The difference between 0.3, 3 or 300K and the 10^9K needed for fusion are all essentially 10^9K.

pressure = n*T, where n is the number density. For fusion you need the triple product of n*T*confinement_time to be greater than a critical value (dependent on the reaction in question). You always need the temperature to be high enough for the reaction to happen at any appreciable rate. So it’s not as simple as increasing density so you can lower the temperature, generally though if you can increase density you can decrease the required confinement time.

As for using the collapsing filaments of a plasma focus device to provide the energy to what is essentially inertial confinement fusion, instead of lasers is an interesting idea, but I think the axial symmetry of the plasma would mean the pellet would be compressed unevenly and squish out of the ends before it could be heated sufficiently.