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Insights Interview with a Physics Mentor: PeterDonis - Comments

  1. Apr 15, 2016 #1
  2. jcsd
  3. Apr 15, 2016 #2
    I just wanted to say I admit I even wrote my own D&D style stories. I think they were pretty good!

    Have you looked at Rust as a programming language?
  4. Apr 15, 2016 #3


    User Avatar
    Science Advisor

    Are ITER's goals technically feasible?
  5. Apr 16, 2016 #4
    What a great interview, I do agree that gravity knowledge is stalled at the moment only confirming today's theories , and my own theory about accelerative expansion (see my discussion on Gravity) is only a confirmation of existing knowledge. I do hope that gravity is explained in my lifetime.
  6. Apr 18, 2016 #5


    Staff: Mentor

    I wrote a bunch of them too; in fact I often wondered if one of my reasons for playing D&D was to generate material for the stories. :wink:

    Only glanced at it. The programming I do doesn't really seem to fit its main use case, which is systems programming. Also, it has the same problem that I attributed to Go in this post on my blog a while back:

  7. Apr 18, 2016 #6


    Staff: Mentor

    This is probably worth a whole post and discussion thread in itself (and also there are regulars in the Nuclear Engineering forum whose knowledge is more up to date than mine and could give a better answer). It seems to me that tokamak fusion has ended up being a much more difficult and costly path than it was expected to be. But at least a fair portion of that is due to issues that are bureaucratic, not technical. We know the plasma conditions we need to achieve: the Lawson criterion. We know there are a number of issues that have to be carefully managed to run a tokamak under those conditions; but at least to an extent we can manage them by brute force while we experiment with ways to do it more cheaply. But to do that requires a commitment something like that of the Manhattan Project or the Apollo program, and tokamak fusion hasn't had that kind of commitment. ITER has had some PR indicating that it is supposed to be that kind of commitment, but it isn't.
  8. Apr 18, 2016 #7


    Staff: Mentor

    I should add that there are some key disanalogies between ITER and the other two programs I mentioned. Unlike in the case of fusion, in the case of fission the controlled reaction yielding energy came first--Fermi's experiments--and then the bomb. Also, the conditions for a chain reaction turned out to be relatively easy to achieve--the fuel is solid, not plasma.

    In the case of the Apollo program, the rocket engines involved were operating at the limits of what could be achieved with known materials and fuels, but the basic physics involved was so simple--basically the rocket equation and orbital mechanics--that there was no doubt that rocket engines of sufficient power could get a spacecraft to the Moon. Whereas with fusion, much of the research over the years has been trying to establish the basic physics--what kind of plasma configuration do you need to achieve the Lawson criterion?

    So there are reasons why fusion research has not been an obvious candidate for a Manhattan Project/Apollo commitment the way those previous efforts were.
  9. Apr 18, 2016 #8
    One of them being that there is no likely strategic military advantage for a nation to go it alone,it only makes sense in the context of international co-operation.
    But then beurocracy, diplomacy, etc, and top heavy management.
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