Momentum from Nothing: Action Without Reaction?

Here's an article about a new paper in Physics Review Letters:

http://focus.aps.org/story/v13/st3

Electromagnetism may allow you to transfer momentum between an object
and the vacuum. If true, this implies a mechanism for propulsion
without propellant mass. The numbers are of too small a scale to fight
the earth's gravity, but perhaps in a weak gravitational field, it
could amount to anti-gravity?

quoting the following:
Both Leonhardt and Loudon warn that the predicted effect may be
difficult to spot. For example, Loudon says, if the material contains
a few freely moving electrical charges, they will experience larger
forces that may obscure the subtle quantum effect. Still, Leonhardt
says, "This is a smart idea."

But if the freely moving electrical charges make it difficult to
detect in the lab, could this other article be of use?
http://www.physicsweb.org/article/news/8/1/9

(sanman) wrote
Electromagnetism may allow you to transfer momentum between an object
and the vacuum. If true, this implies a mechanism for propulsion
without propellant mass.

You can push on the Earth's magnetic field. Check out:

http://tethers.com/EDTethers.html

Also my simulator at http://spacetethers.com/spacetethers.html can
simulate the physics for this. The Earth's field drops off fast,
so you probably only want to do this in LEO. But you can use it
to boost a momentum exchange tether which can toss something
further.

-- Vince

(Vincent Cate) wrote in message . com...
(sanman) wrote
Electromagnetism may allow you to transfer momentum between an object
and the vacuum. If true, this implies a mechanism for propulsion
without propellant mass.

You can push on the Earth's magnetic field. Check out:

http://tethers.com/EDTethers.html

Also my simulator at http://spacetethers.com/spacetethers.html can
simulate the physics for this. The Earth's field drops off fast,
so you probably only want to do this in LEO. But you can use it
to boost a momentum exchange tether which can toss something
further.

-- Vince

But dude, the article I'm talking about might be applicable to
propulsion thru space in general, and not merely in the presence of
the earth's magnetic field. Yes, I've read about tethers and
geo-magnetic orbital maneuvering, but what about being able to
maneuver in space, away from the earth? Granted, you'd need a very
large magnetic field, but what if you could apply the tether principle
to momentum exchange with the vacuum? Could you have a spacecraft with
a large tether on it propelling itself thru interplanetary space, or
even interstellar space, where no external magnetic field is present?
At least that way, you wouldn't need any propellant mass to be
expelled from the spacecraft. That kind of mass savings would be very
significant, especially over a long voyage, to a nearby star for
example.

But I'd agree, it's probably easier and more efficient to interact
with the earth's magnetic field rather than to interact with the
vacuum. But if you've got no external magnetic field handy, then
momentum exchange with the vacuum would be available. Too bad the
impulse numbers are so low, but perhaps a lightweight tether that is
many miles long might make up for that.

(sanman) writes:

Here's an article about a new paper in Physics Review Letters:

http://focus.aps.org/story/v13/st3

Electromagnetism may allow you to transfer momentum between an
object and the vacuum. If true, this implies a mechanism for
propulsion without propellant mass. The numbers are of too small
a scale to fight the earth's gravity, but perhaps in a weak
gravitational field, it could amount to anti-gravity?

Propellant-less propulsion maybe, anti-gravity no.

quoting the following:
Both Leonhardt and Loudon warn that the predicted effect may be
difficult to spot. For example, Loudon says, if the material
contains a few freely moving electrical charges, they will
experience larger forces that may obscure the subtle quantum
effect. Still, Leonhardt says, "This is a smart idea."

I think emerging nano technology will still provide us with a few
surprises. At the nano scale there may yet be some undiscovered
physical properties in some materials.

The quantum effect mentioned might be small, but if harnessed by a
trillion nano devices in parallel it may become significant enough
to be useful for inter-planetary or even inter-stellar, propellant-
less propulsion.

--
Manfred Bartz
---------------------------------------------------------------------
Any technology distinguishable from magic is insufficiently advanced.

Manfred Bartz writes:

(sanman) writes:

Here's an article about a new paper in Physics Review Letters:

http://focus.aps.org/story/v13/st3

Electromagnetism may allow you to transfer momentum between an
object and the vacuum.

_DON'T BET ON IT_. It's =FAR= more likely that the author of the paper
http://www.arxiv.org/abs/physics/0304100 has made an error, and even
MORE likely that the AIP PR flack who wrote the press release has NO IDEA
WHAT HE IS TALKING ABOUT, and has made ABSURDLY WRONG CLAIMS in the process
of "punching up" the article to make it sound more "Paradigm Shattering."

Furthermore, as I have pointed out =MANY= times before, Julian Schwinger
has shown that =ALL= of the alleged effects attributed to "the vacuum"
can be =FAR= more simply and rationally attributed to DIRECT INTERACTION
BETWEEN MATERIAL OBJECTS, rather that "modifying the boundary conditions
of the vacuum." I continue to maintain, as did Schwinger, that "vacuum
energy" and "vacuum momentum" are a BUNCH OF BLETCHEROUS BOVINE BYPRODUCT,
and furthermore assert that this "effect" is NO EXCEPTION. Here's why;
note the exact claim in the PR release:

Feigel next used his theoretical tools to analyze the momentum
inside a material placed in strong, perpendicular electric and magnetic
fields. He found that virtual photons traveling through the material
would have a strange asymmetry. If the electric field pointed up and the
magnetic field pointed north, then virtual photons of a given energy
traveling east would have a different momentum from those traveling
west. That asymmetry would give the vacuum a net momentum in one
direction, and the material would have to gain momentum in the opposite
direction to compensate. In fields of 100,000 volts per meter and 17
tesla--which can be created in the lab--the material should move at a
rate of 50 nanometers per second, Feigel says, which should be
measurable.

Now ask yourself: What is _CREATING_ those crossed electric and magnetic
fields? Obviously, THERE MUST BE EXTERNAL FIELD PLATES AND FIELD COILS.
Now, BY DEFINITION, "virtual photons" =CANNOT= just terminate on "nothing;"
they must be emitted and absorbed by SOME MATERIAL SOURCE --- to wit,
the dielectric, the electric field plates, or the magnetic field coils.
I am _ABSOLUTELY CERTAIN_ that if one does a =CAREFUL= analysis of Feigel's
"effect," his alleged "vacuum momentum" will turn out to NOT EXIST, and
instead there will be AN EQUAL AND OPPOSITE RECOIL IN THE FIELD-GENERATING
APPARATUS. The energy and momentum both have to come from =SOMEWHERE=, and
that "somewhere" is the electric field plates and magnetic field coils.
All Feigel has done is come up with a particularly wimpy and ineffective
electromagnetic catapult. THERE IS NO SUCH THING AS A FREE LUNCH.


If true, this implies a mechanism for propulsion without propellant
mass.

I =VERY= strongly doubt it --- see above.

The numbers are of too small
a scale to fight the earth's gravity, but perhaps in a weak
gravitational field, it could amount to anti-gravity?

Propellant-less propulsion maybe, anti-gravity no.

Propellant-free propulsion, no --- and it It has NOTHING WHATSOEVER
to do with gravity or the bull$#!+ nonsense lumped under"anti-gravity" !!!


quoting the following:
Both Leonhardt and Loudon warn that the predicted effect may be
difficult to spot. For example, Loudon says, if the material
contains a few freely moving electrical charges, they will
experience larger forces that may obscure the subtle quantum
effect. Still, Leonhardt says, "This is a smart idea."

IMO, Loudon COULD NOT POSSIBLY BE MORE WRONG: This is Yet Another Example
of what happens when someone _FAILS TO THINK THE PHYSICS THROUGH COMPLETELY_,
and instead relies on PHYSICALY NON-EXISTENT "folk theorem" concepts such as
"vacuum energy" or "vacuum momentum."


I think emerging nano technology will still provide us with a few
surprises. At the nano scale there may yet be some undiscovered
physical properties in some materials.

The "nano scale" is simply the atomic scale. All experimental evidence
indicates that conservation of energy =STILL= holds for atoms, that
conservation of linear momentum =STILL= holds for atoms, and that
Newton's Third law of Action and Reaction =STILL= holds for atoms.
THERE IS NO SUCH THING AS A FREE LUNCH --- even using nanotech.


The quantum effect mentioned might be small, but if harnessed by a
trillion nano devices in parallel it may become significant enough
to be useful for inter-planetary or even inter-stellar, propellant-
less propulsion.

I repeat: THERE IS NO SUCH THING AS A FREE LUNCH --- even using nanotech!
The energy and momentum have to come from =SOMEWHERE=. That "somewhere"
is the electric field plates and magnetic field coils. All Feigel has done
is come up with a particularly wimpy and ineffective electromagnetic
catapult. And once again: _THERE IS NO SUCH THING AS A FREE LUNCH_.


-- Gordon D. Pusch

perl -e '$_ = \n"; s/NO\.//; s/SPAM\.//; print;'

Manfred Bartz wrote:

I think emerging nano technology will still provide us with a few
surprises. At the nano scale there may yet be some undiscovered
physical properties in some materials.

The quantum effect mentioned might be small, but if harnessed by a
trillion nano devices in parallel it may become significant enough
to be useful for inter-planetary or even inter-stellar, propellant-
less propulsion.

Do be aware that reactionless propulsion is mathematically equivalent
to a perpetual motion machine of the first kind (if the phenomenon
occurs the same way in any inertia reference frame.)

Paul

"Paul F. Dietz" wrote in message ...
Manfred Bartz wrote:

Do be aware that reactionless propulsion is mathematically equivalent
to a perpetual motion machine of the first kind (if the phenomenon
occurs the same way in any inertia reference frame.)

I keep hearing these kinds of statements. Please give me a practical
example
of how you could exploit a reactionless drive to make a perpetual
motion
machine.

Anyway, if you just use a light bulb as an engine, you've got
propulsion without having to carry a specific reaction mass.