[extropy-chat] unidirectional thrust

[Hal Finney]

Mike Lorrey writes:
> --- Hal Finney <hal at finney.org> wrote:
> > Personally I'm a big fan of conservation of momentum.  I don't see
> > any way these devices can work unless they are pushing on air or some
> > other material medium.  I can't see a role for Mach's Principle or
> > any other exotic relativistic physics.  Is something moving at
> > relativistic speeds here?  I don't see it.
>
> You aren't supposed to see it, it is a field effect.

I'm not supposed to see something moving at relativistic speeds, we agree?
Do you or don't you think that relativistic effects are present here?

> The question remains, I posted a link to a paper that showed that ion
> wind can only explain a small percent of the actual thrust observed,
> contrary to NASA claims.

Are you talking about
http://www.geocities.com/ekpworld/doc/EKP_satellite_maneuvering.doc ?
Or some other paper?

If that one, he only shows what you claim with respect to a 1e-5 torr
vacuum.  He doesn't make any such claims with respect to operation in air.
Do you agree?  If not, please point me to where that is said.

And this depends crucially on what the actual thrust observed is in
such a hard vacuum, that this must be greater than his calculations
based on air movement.  But he doesn't provide any details of his
experimental methodology.  What kind of vacuum pump did he use?
What was his experimental setup?  How did he measure thrust?  The paper
says nothing about this.  How seriously can we take his claim of such
strong thrusts in a hard vacuum, when other researchers have failed
to detect thrust in a vacuum (according to the Wikipedia article
http://en.wikipedia.org/wiki/Biefeld-Brown_effect , thanks, Dirk).

> Given the sort of performance Naudin has
> shown, he should also be showing some rather significant ion wind to
> generate that kind of thrust, something that would be quite detectable
> and measurable.

I agree.

> He does have a page showing that he separated the electrodes entirely.
> If it were ion wind, it wouldn't travel through the barrier he imposed
> between the electrodes.

Which page is that?

...

> It depends on what you mean by 'uncompensated thrust'. Conservation of
> energy doesn't make this illegal, because you are putting a significant
> amount of power (i.e. work) into creating this Lorentz field effect. I
> would say that for the amount of power expended, it may be considered
> rather inefficient, power wise, compared to more conventional methods.

And where is this work supposed to be going?  What is it acting on?  What
gains energy when this device loses energy, as is required if energy is
conserved?

> Nor would I say that it ultimately violates conservation of momentum or
> Newton's laws, it merely uses a field effect to do work within the same regieme.

If the gadget starts going forward and there's nothing else that starts
going backward, by definition that violates conservation of momentum,
right?  If this thing starts out stationary in empty space, and you turn
it on and after a while it is moving, then its momentum has changed.
Unless there's something else moving in the opposite direction, as with
a rocket, you are violating conservation of momentum.  All such "space
drives" including your Lorrey Drive, violate conservation of momentum,
as far as I can see.

Hal