The conversion that you speak of is not as simple as it seems. If linear
momentum is all that you have in the beginning then any generated angular
momentum will always have an opposite brother that exactly negates the total
when vector summed. Of course this is only true for a closed system.
Dave
-----Original Message-----
From: Vibrator ! <mrvibrat...@gmail.com>
To: vortex-l <vortex-l@eskimo.com>
Sent: Thu, Dec 29, 2016 2:31 pm
Subject: Re: [Vo]:EM Drive need not be outside the spacecraft
LOL simply converting angular to linear momentums is trivial - think of a
piston and crank, ball billiards or whatever..
What you're on about is varying net system momentum - ie. an N3 violation,
linear or angular. Sure, if the motor's off then CoM / CoAM applies, and
momentum's constant. I'm not sure anyone's suggested otherwise..
But a tethered EM drive is not producing counter-torque, so net angular
momentum would not be constant...
...and if it were switched off mid-flight, and whatever it was tethered to
suddenly released to move freely, the whole rotating system would fly off in a
straight line, the two masses orbiting eachother as they fly thru space
forever, their center of mass following a straight line.
Which is not to suggest that reactionless torque can necessarilly be converted
to reactionless linear force - although i've seen at least one suggestion that
a pair of opposing-signed 'angons' nailed to the same base would generate a net
linear force, forming a 'linon' - an intruiging thought nonetheless LOL..
The suggestion that linear can be converted to angular was yours, remember...
you were saying that an EM drive tethered this way demonstrates a further
conservation violation.
I'm simply pointing out that inertia doesn't care what the direction of
acceleration is, it's purely a function of how much mass has been accelerated /
through how much space & time. Linear inertia is invariant due to mass
constancy, while angular MoI is a variable function of mass times radius. But
either way, the energy disunity is between the savings made on inputting
momentum from within the accelerating frame, versus its usual KE value as
measured from the external static frame, where N3 still applies - it's an
excess of output work by the Higgs field, in relation to a deficit of input
work on the part of our accelerating net system momentum.
My point's simply that there's no logical paradox or supernatural invocations
etc. - the resolutions are already implicit within the terms of the
proposition. Any symmetry break implies an open thermodynamic system, and the
source or sink is whatever's responsible for the passive force/time variation.
This applies to all of them - overunity or underunity - all we're talking about
is work performed by forces, or else its absence.
The argument that a claimed non-classical thruster can't work because it would
violate classical laws just seems kinda redundant.
On Thu, Dec 29, 2016 at 5:55 PM, Stephen A. Lawrence <sa...@pobox.com> wrote:
On 12/29/2016 12:46 PM, Vibrator ! wrote:
What's wrong with the centripetal tether example?
With the engine turned off (no thrust) putting the tether in place doesn't
change the angular momentum at all. The cross product of the linear momentum
of the object with its radius vector remains unchanged. Since it's exerting no
torque on the pivot, that must be true, classically.
Meanwhile, the linear momentum of the tethered object is changing constantly,
as its velocity vector rotates. But it's also exerting a force on the pivot
point, as a result of which the linear momentum of whatever the pivot is
anchored to is also changing constantly, in such a way that the sum of the two
remains constant. (Energy, not so much, as it goes as the square of the
velocity and hence has zero derivative WRT velocity at zero velocity.)
There's no interconversion between linear and angular momentum. As I already
said, they're conserved separately.
