[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heard of this?")
- From: Willow Schlanger <wschlanger@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Mon, 04 Aug 2014 19:33:56 -0700
NASA wouldn't have published an AIAA paper on an "over unity"
experiment. It is possible to "seem to" violate momentum conservation
but still be in line with the laws of physics, including energy
conservation (as long as you don't really violate momentum
conservation). The AIAA papers (there are two of them and I'm still
getting motivated to work my way though them) do not mention perpetual
motion.
It is the folks on this list that have treated this as a claim of a
"reactionless drive," whereas it's really a proposal for a possible
"propellantless drive" that doesn't carry its own stuff to use for the
reaction that needs to conserve momentum (and make energy conservation
and all the known laws of physics still work).
The idea that quantum plasma or anything related is what conserves
momentum is interesting, if unproven. Maybe once that "quantum plasma"
gets accelerated, if indeed that is what happens, it pushes space debris
or other objects away, ultimately conserving momentum after-all (if
indirectly?) In this case our drive's efficiency could perhaps vary
depending on what it's ultimately pushing against, falling to 0 if
there's nothing to react against but still not requiring its own propellant?
It is true that if momentum were not conserved at all, many reference
frames would exist where energy conservation would be violated. For
example, in some reference frames, the device would mysteriously slow
down instead of speeding up (while still consuming some internal energy
as before). That represents the loss of energy into nowhere (this can't
be easily corrected, though if there's some exhaust moving the opposite
direction that reference frame would show the exhaust having increased
in speed, thus conserving energy and momentum and being permissible).
Key questions are: 1) does this work at all; and 2) is it significant
(i.e. is this something new), or is it useful? Having this discussion is
worthwhile, but we're degenerating into speculation.
I suppose I could discredit a project really well by over-hyping it,
even mixing in references to black holes and perpetual motion! But
aren't we smart enough to know better?
Again, if there's a box you turn on and at the end of the day its
velocity has changed (even when you compute the mass * velocity, i.e.
momentum, of all of its parts); and it continues to increase velocity in
the same direction, using up only a reasonable amount of energy, then we
have a possible problem here UNLESS if you wait long enough you realize
other things nearby are affected to somehow conserve momentum.
If this is done via some kind of field, it would be interesting: the
device's performance could be measured (newtons per watt) and nearby
objects could perhaps affect that performance. If it's in free space,
away from all stars and planets (and assuming quantum "plasma" thrusters
aren't really possible as an end-game but only perhaps as a theory about
how we get to the final state), we'd expect efficiency to be close to 0,
as then there'd be essentially nothing that could be pushed away.
If there's a dense planet or moon nearby (the Earth in the case of this
experiment), perhaps that thing is interacted with via a field so as to
still conserve momentum, and depending on its mass and the relative
velocity of that and the device with this "EmDrive" inspired device,
we'd experience more than 0 efficiency; but exactly how much more, could
perhaps vary depending on the device's ability to interact with those
moons or planets to honor conservation laws.
In other words, even if this isn't useful for propulsion, perhaps it can
be useful to measure the density of stuff beneath our feet (or in the
ocean)? Laser interferometers can be used between a pair of satellites
in space to precisely measure their distance from each other. From those
distance measurements, one can reconstruct images of continents, where
one is measuring the density of the Earth beneath the satellites, using
gravitation itself and not electromagnetism at all.
This is interesting because gravitation is not licensed or regulated,
and no one knows how to shield it (so if you build a very, very, very
big "secure area" and keep giant secrets in it, someone can peer inside
passively via gravitation and get an idea of what you're doing in there,
even if you secured it against electromagnetism).
Being able to determine the density of something near-by a device like
this (or to peer within the Earth without needing a pair of satellites
far away from the area of interest) would be exciting and useful.
It's optimistic though, to imagine this device or (any other
electromagnetic device, Biefield-Brown or otherwise) has anything to do
with gravitation. I haven't heard a credible report of a capacitors'
mass to weight ratio changing in response to a change in its internal
energy or the extent to which it is charged.
Of course we know its effective rest energy must increase a bit when it
gets an increase of potential energy (i.e. if it becomes capable of
doing work to the outside world because it's charged up, then its energy
has increased and effective mass has also increased by 1/C^2 times as much).
Presumably if the capacitor is moving, its momentum has then changed in
response to being charged up (but the momentum of whatever charged it up
-- say a battery that lost energy so the capacitor could gain energy,
would have similarly changed so momentum is still conserved).
Before the Townsend Brown guy, there was James Clerk Maxwell who, in
addition to proposing the Maxwell demon thought experiment, proposed
having a positive and negative charge separated by an insulating rod,
and he wasn't clear on why it wouldn't accelerate on its own if it was
already moving, because he felt there'd by a delay in information
propagation (the charges were supposed to be responding to the position
of where the other charge was a little bit in the past).
In a nutshell that's "reaction-less" propulsion also. No one's looking
into this, though, because how much force (or energy) you get for free
depends on the reference frame, meaning the conclusions are absurd and
not Lorentz invariant (I'm not sure how this is resolved, but probably
it's done by using special relativity and all 4 of Maxwell's equations;
I think he proposed this idea before they were all fully derived).
However, the mere possibility of potential energy having momentum cannot
be discounted. If a capacitor can be charged up and experience a change
in linear momentum (at the expense of the momentum of whatever provided
the energy to charge it), the two must be related.
Measuring this would be very difficult, and relating it to angular
momentum would be a great idea since the latter is known to be quantized
(and is conserved just like linear momentum).
Still, I was hinting at a possible physical route here: maybe our
"EmDrive" derived device does work after-all, and measurements of its
efficiency would reveal information about how dense objects in its
vicinity are? So you might aim for propulsion to the stars, and wind up
instead with a scale that works without contact (that'd still be cool!)
and can peer within the Earth to find oil or whatever.
If this drive does work, momentum conservation is mandatory at the end
of the day (otherwise we'd have this "over-unity" problem that
discredits the effort quite nicely!) But maybe momentum is conserved via
a change in potential energy, via some unknown route?
Willow Schlanger
On 08/04/2014 05:42 PM, Michael Clive wrote:
> Monroe, it requires money to get vacuum pumps, chambers, interfeometers, RF
> amplifiers, DAQ systems, structural equipment. It requires money to get the
> systems to a level of sophistication that the data produced by them will be
> trusted. It takes money to have calibration labs verify your equipment, and
> it takes money to publish results, host websites, etc.
>
>
> Since the possibility of this being an over-unity device has been raised, I
> am really unenthused about the project now. I don't waste time with
> perpetual motion machines.
> Bummer!
> If anyone can counter Pierce's argument, I would love to hear about it!
>
>
>
> On Mon, Aug 4, 2014 at 1:22 PM, Monroe L. King Jr. <
> monroe@xxxxxxxxxxxxxxxxxx> wrote:
>
>> Why do you need $100k to build one of these? The more I look into it I
>> don't see where you need it. I can try this in my shop.
>>
>> What's going on here? I don't get it? Is it a schema to raise money for
>> research? What's the pitch?
>>
>> A simple interferometer should be sufficient for the measurement.
>>
>> I can pull 10 to the 8th torr
>>
>> I can machine the parts it looks like.
>>
>> What else do you need?
>>
>> Monroe
>>
>>> -------- Original Message --------
>>> Subject: [AR] Re: NASA test of quantum vacuum plasma thruster (was
>>> "Anyone heard of this?")
>>> From: Peter Fairbrother <zenadsl6186@xxxxxxxxx>
>>> Date: Mon, August 04, 2014 12:35 pm
>>> To: arocket@xxxxxxxxxxxxx
>>>
>>>
>>> On 04/08/14 17:47, Ian Woollard wrote:
>>>> On 4 August 2014 16:54, Peter Fairbrother <zenadsl6186@xxxxxxxxx
>>>> <mailto:zenadsl6186@xxxxxxxxx>> wrote:
>>>>
>>>> Suppose, as has been claimed, the drive is somehow exchanging
>>>> momentum with the entire universe. The momentum of the universe may
>>>> have a (?local) velocity - which would be mathematically equivalent
>>>> to a preferred frame of reference.
>>>>
>>>> If so, there need be no violation of either of the conservation
>> laws.
>>>>
>>>>
>>>> Even that wouldn't be of any practical use for propulsion.
>>>>
>>>> There's basically zero chance that you would moving close the preferred
>>>> frame of reference's speed. And if you're not.. .big trouble in little
>>>> china.
>>>>
>>>> To see this, consider that we're already going at (say) >300km/s due to
>>>> orbital speed, the speed of the Sun within the local cluster and the
>>>> orbital speed around the Milky Way, and the speed of the Milky Way
>>>> relative to other galaxies... so it takes enormous energy to make quite
>>>> modest increases in speed because energy goes as 0.5 m V^2.
>>>>
>>>> i.e.
>>>>
>>>> E = 0.5 m V^2
>>>>
>>>> where V is the speed in the preferred frame of reference.
>>>>
>>>> differentiating wrt time:
>>>>
>>>> P = m V dV/dt
>>>>
>>>> dv/dt = P/mV
>>>>
>>>> so acceleration for any given power is inversely proportional to
>> initial
>>>> speed. That's the same reason cars accelerate very fast initially, and
>>>> then accelerates ever more slowly. But here you would be going at
>>>> extreme speeds to start with. Rockets and ion drives circumvent this
>> due
>>>> to Oberth effect and get constant acceleration from constant power.
>>>>
>>>> Plugging in numbers here it would cost 300kW to accelerate 1kg by
>> 1m/s^2
>>>> which is insanely inefficient.
>>>
>>> So, 300 kW per N.
>>>
>>> The highest claim in the paper, afaict, is 17 W for 91 uN - or 186 kW
>>> per N, not so different.
>>>
>>> There may also be local issues, eg the Milky Way's mass may drag an
>>> effective local frame velocity zero closer.
>>>
>>> And what about if you want to go sideways?
>>>
>>>
>>> The point I am trying to make (while I don't actually believe in the
>>> thruster at all) is if the explanation is as above, if the quantum
>>> vaccuum has a (?local) velocity, it does not violate Newtonian physics
>>> or Special Relativity - it just adds a single new item, the local
>>> velocity of the universe, to the laws of physics.
>>>
>>> And maybe it answers a long-standing question about Special Relativity
>>> too - the universe does in fact seem to have some sort of preferred
>>> frame of reference. That is unexplained in SR.
>>>
>>> There is also an asymmetry in SR time dilation which it also might help
>>> explain as well, but probably better offlist.
>>>
>>>
>>>
>>> We do not know all the laws of physics. Not even close.
>>>
>>>
>>>
>>> -- Peter Fairbrother
>>
>>
>
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