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Re: starship-design: Wild thoughts

We're getting somewhere now. Steve's answer here reminded me that I had
inaccurately portrayed energy storage systems as not increasing in mass with
energy, as I was pointing out our building starships with monster fires in them
might have more to do with our primal urge to build fires, than with the needs
of starships.

Steve VanDevender wrote:

> Antonio C T Rocha writes:
>  > Just fantasizing, of course, but :
>  >    Counter-rotating masses of superconducting stuff (a condensate?) carrying
>  > static circular current. Compensating for one another.
>  >    Gues I'll toy with that one for a while.
>  >
>  > Antonio C T Rocha
> Superconductors have this problem where a magnetic field above a
> certain strength breaks down their superconducting properties.
> This puts a limit on how much current any superconductor can
> carry, since the current creates a magnetic field around the
> superconductor.
> One amusing feature of relativistic kinematics is that while one
> photon is massless, two or more photons treated together as a
> system usually aren't (unless they are all traveling in exactly
> the same direction).  So, for example, if you could create a
> fiber-optic ring and pump a large amount of laser light into it,
> you would make it heavier; the sum of the energy-momentum vectors
> of all the photons in the ring would add up to an energy-momentum
> vector that has a mass.  The ring also has to exert a centripetal
> force against all the photons bouncing around its outside to keep
> them contained, so eventually you could rupture the ring by
> putting enough photons into it.
> In any case, stored energy _is_ mass.  If you can somehow cram a
> tremendous amount of energy into any kind of container, it gets
> more massive.  Normally the amount of stored energy in things
> like chemical batteries or warm objects is too small of a
> fraction of the total mass to measure, but there's really no way
> to make an exotic battery that can hold an amount of energy on
> the order of its own mass where it won't get more massive as you
> charge it up.

The inertial business of moving the ship requires a harder push for a
ship with lots of stored energy, so in effect its mass has indeed
increased. That statement is neutral in the selection between a fueled
fiery ship, and another ship design using cold stored energy with
electrical tools of propulsion, like an accelerator.

But I felt like I was getting into Steve's mind a bit
during this realization. I kind of got a flash of like telepathy,
because all of a sudden I realized he was trying to
think of something, and it was something I was also
trying to think of, and didn't know it.

Anyway, what I think it was, was we were both
desperately trying to remember a centripetal factor,
which would hold a ring of relativistic particles
together. Of course the answer is gravity. If the
speedy little rascals are getting effectively heavier,
they're radiating gravitons, which will intercept and
interact with all the other parts of the ring, most
effectively with the ring segment directly opposite.
Geons are what self gravitating magnetic fields are

At the threshold where you first get the speed of the
particles just right to make the ring hold together,
you get a critical band of velocities for the ring
particles, within which you can adjust factors such
as the size of the ring. By moving the particles a bit
faster, you increase the gravity and shrink the ring.
Within the ring is a microgravity environment.

It's time to haul out the old sorceror to wrap the
ring in a spiral sheath of electrons, to hold the ring
all together. The core of the ring is made of relativistic
protons hung on magnetic field lines, all together.
These electrons are slower than the protons, because
they are not relativistic. They move at exactly the ( helical )
orbital velocity around the ring, very near its surface,
under the combined attraction of gravity and charge.
Charge predominates so much, that the gravitational
difference an electron feels inside and outside the ring
does not grossly affect the orbital shape.

The choice you have, in choosing the handedness or
direction of the spiral sheath of electrons, is whether
you want to boost or buck the gross magnetic field
of the ring's protons. Counterrotating flywheels was
just suggested in here, by Antonio C T Rocha.
Generalizing to rings in this case, counterrotating
rings would establish rigid structure for the extended
( unpressurized, not in solid contact ) portion of the
ship. Rings of opposite spin are repulsive, so a very
stable equilibrium can be established, by balancing
that repulsion against the gravitational attraction
which wants to bring the two rings together. The
best idea seems to set the spiral sheath to boost
the proton magnetic field, and to use two mutually
repulsive rings around your ship. That seems to
give a robust structure to the ship complex, to
get better scores on the crash tests and so forth.

There is a convenient zone between the rings where
everything cancels out, gravity, charge and magnetism,
and it's just like down home in outer space. That's
where your ship sits.

So do we have the possibility of a stored energy
solution here? The battery is shaping up, as those rings.

Johnny Thunderbird
-=Scythian WebRing=-