Tom Rux wrote:
> How much stress does that acceleration place on the launching
> mechanism and materials that make up the system?

Acceleration from zero to 1km/sec in about 1m?

Velocity v, acceleration a, distance s:
v^2 = 2as

v = 1000m/s
s = 1m

a = (1000^2)/2*1 = 500,000m/s^2 or 50,000g

So we're in artillery round territory here.
Peak acceleration for bullets is up to 4x higher.

5km/sec final velocity requires 1.25 million g.
This is beyond yield strength for conventional materials.

Etc.

Andy Long wrote:
> 1. If it's accelerating under the influence of a uniform gravitational
> field along it's length,
> then there's no stress.

Preferred option. The missile and surrounds experience no stress. From the
missile's POV, the launching system is accelerating away from it.

> 2. If it's accelerating under the influence of a generated point source
> "in front" of it,
> then indeed there might be gravitational stresses on it...

Kind of like grav focusing for lasers, but worse (why doesn't the rest of
the ship get attracted towards the pseudomass too)?

Tom again:
> The thrust appears to be discharged from the stern on the spacecraft.

They're running lights to show everyone the drive's on rather than some sort
of reaction mass being discharged, hence the term 'reactionless'. Or maybe
they're bogon particles that don't interact with ordinary matter.

> Of course my opinion is based on being aboard a submarine...

Torpedoes push against the water to move.
SLBMs get kicked out by high-pressure steam to eject the missile out the sub
in the case of U.S. missiles. The Soviets probably did something similar
with their gas launching systems.

Kurt Feltenberger wrote:
> I like the sci-fi aspect where things we don't know today, or
> don't even conceive of today, are possible tomorrow using concepts that
> to us are what a 747 or SSN would be to someone from 1000AD.

I get tired of this variation of the argument from ignorance.

Pi doesn't stop being pi in the Far Future.
Gold will still have an atomic number of 79.
Light will always be a particle and a wave.
Etc.

Knowledge is additive.
What we know now doesn't go away because it's the day after tomorrow.
Its importance will change.

Technology will change. But it will have limits and will be internally
consistent.

I don't mind 'magic' technology either. Thought needs to be put into it,
though, to prevent stupid consequences.

"Guns made of marshmallows and candy sprinkles with infinite ammunition
capacity" give me the shits.
They do nothing for my 'sensawunda' and really detract from my enjoyment of
a game or story.

Just another gamer's thoughts.

Rob O'Connor