On 7/11/21 11:13, Jonathan Clark - jonathan at att.net (via tml list) wrote:
> Now I'm a story-telling GM, not a gear-head, but I do have a little
> background
> in physics, and a perhaps overly vivid imagination... :-)
>
> Alex Goodwin - alex.goodwin at multitel.com.au writes:
>
>>     Those messy neutrons, and the energy they carry off...
>
> But but but... Once you have control of gravity, you can likely build
> a reactor
> which can confine the said neutrons, and extract at least some of
> their energy.
> OK, at low TLs you might have to wait until they decay and then soak
> up the
> energy of the resulting protons. This all means that the numbers can
> be, well,
> pretty much anything you want within the limits you mention.
>
> The higher the TL, the more options you likely have.
>
> I also mention that if you have grav, you almost certainly have
> control of the
> strong and weak forces, which opens up all sorts of other
> possibilities: a
> direct hydrogen + deuterium -> helium3 fusion path, you name it.

I didn't actually mention anything about "messy neutrons" - I think that
was one of the Jims.

IIUC, an upper bound on fusion efficiency is the relative mass deficit
between the reactants and the products - assuming you catch the direct
energy released, the kinetic energy of the products, and of the decay
products.

How does your assumption of having grav "almost certainly" imply control
of strong and weak nuclear forces?  Is that because in our current take
on grand unified theories, gravity is the sticking point?

Alex