[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heardof this?")
- From: Pierce Nichols <piercenichols@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Mon, 4 Aug 2014 10:17:44 -0700
The device described on the emdrive.com site can be used to build a
perpetual motion machine. It doesn't just violate Newton's third law; it
violates conservation of energy. The technique I will describe will work
with any reactionless drive, regardless of mechanism. I'll start with their
most outlandish claim -- that they can build a drive with a thrust of
30N/W, and work backwards to the claimed experimental results.
Let us presume that we have a 30N weight (like all the numbers here,
selected to make the arithmetic easy). Let us further presume that it is
supported against gravity by a 30N thrust EM drive, and that air resistance
can be ignored for the purposes of this quick demonstration. Now let's give
it a small upward kick, say 0.1 m/s. After 10 seconds, it's 1m higher than
it started, still going 0.1 m/s. Therefore, its kinetic energy hasn't
changed, but its potential energy has. It's a 30N weight and its height has
increased by 1m, so it has gained 30J of potential energy. However, we've
only spent 10J (1W x 10s)... for 20J of readily usable energy that we have
just produced, apparently by magic.
One can argue that a lower thrust to power ratio will fix the issue.
However, since our initial upward velocity in this thought experiment comes
from some other source, we can always increase it such that we're getting
more potential energy out than we put in to the drive... up until we reach
the speed of light. And at that point our thrust to power ratio is
identical to the radiation pressure, which we know is a real effect.
Let's take, for example, the NASA tests. I haven't had time to read the
paper in depth (thank you Clive), but at a skim, it appears that they are
claiming a thrust to power ratio of 2 uN/W. The required upward velocity to
violate energy conservation is 500 km/s. That's infeasible for engineering
reasons... but it's not relativistic by any stretch of the imagination.
-p
On Mon, Aug 4, 2014 at 9:14 AM, <rclague@xxxxxxxxx> wrote:
> One man proposes to build an experimental apparatus. Another man invokes
> authority.
>
> One of these is science. The other is not.
>
> Clive, I'm in for $10.
>
> -R
> Sent from my Verizon Wireless BlackBerry
> ------------------------------
> *From: * David Gregory <david.c.gregory@xxxxxxxxx>
> *Sender: * arocket-bounce@xxxxxxxxxxxxx
> *Date: *Mon, 4 Aug 2014 07:52:30 -0700
> *To: *arocket@xxxxxxxxxxxxx<arocket@xxxxxxxxxxxxx>
> *ReplyTo: * arocket@xxxxxxxxxxxxx
> *Subject: *[AR] Re: NASA test of quantum vacuum plasma thruster (was
> "Anyone heardof this?")
>
> You're going to spend 100k to test a machine that appears to violate
> Newton's third law?
>
> On Aug 3, 2014, at 11:14 PM, Michael Clive <clive@xxxxxxxxxxx> wrote:
>
> my idea is just,well, build enough of these things, test em, and let the
> data rule all. The math will come after. The capital outlay is in the 100k
> range, which is feasible for a crowdfund/private partnership.
>
>
> On Sun, Aug 3, 2014 at 9:04 PM, <joesmith@xxxxxxxxx> wrote:
>
>> In the late 1890's Marconi invented the wireless,working off the efforts
>> of such as
>> Henry,Maxwell and Hertz.
>> The world was changed overnight,forever after.
>> Logically we should have to ask not ''when'' but ''how soon'' and
>> ''who''.
>> Nobody can deny the technology exist,,but how do we tie it together as
>> the
>> 20 year old Italian did?.
>> Don't you think that it is about time to come un-STUCK?
>>
>>
>> On Sun, 03 Aug 2014 17:47:11 -0700, "Monroe L. King Jr." <
>> monroe@xxxxxxxxxxxxxxxxxx> wrote:
>> There is the theory Hawking Radiation (which was mostly proven wrong)
>>
>>> But there is the radiation emitted from black holes. It takes a hell of
>>> a gravity well to produce it. But as the particles reach the horizon
>>> it's like there it produces a particle and an anti particle and one
>>> falls over the horizon and the other escapes if they do no annihilate
>>> each other first. For me that explains why we have more matter than anti
>>> mater in our universe. Black holes sweeping up the floor all the time
>>> for eons.
>>> I am sure you guy's could care less what I think. But it's going to
>>> take a hell of a lot of energy to make the next breakthrough (like a
>>> tiny black hole) or being able to actually see the event horizon and
>>> measure something from a far off black hole (Like the massive one at the
>>> center of our galaxy) But Hawking was trying to explain why or where the
>>> matter goes? Why not a "Big Bang" on the other side? Why not if the
>>> gravity is so
>>> great the singularity smashes down so far to the Higgs or beyond and
>>> that energy is expelled into another universe?
>>>
>>> One thing is for sure they don't expel anything but some minor
>>> radiation in our universe. Where does all that matter go?
>>>
>>> Black holes do die! They eventually evaporate.
>>> Anyway bla bla bla. With no proof.
>>> Mathematics is like building skyscrapers with geometric shapes that
>>> seem to resemble something we call building blocks. Lots of ways to
>>> build something but eventually you reach the top. We have whole cities
>>> of blocks that over time we have made fit together.
>>> We are at the pinnacle of what we can do with our building blocks made
>>> of stone. So what we have to do now is discover steel and concrete.
>>> The new cities we build will look nothing like the ones we have now.
>>> Maybe a bit here some architecture there you can recognize. But beyond
>>> that it just wont be the same anymore.
>>> That's how far we have come. Pretty damn far! But we are so so so very
>>> far from understanding it all it's not even funny.
>>> Monroe > -------- Original Message --------
>>> > Subject: [AR] Re: NASA test of quantum vacuum plasma thruster (was
>>> > "Anyone heard of this?")
>>> > From: Ian Woollard<ian.woollard@xxxxxxxxx>
>>> > Date: Sun, August 03, 2014 3:09 pm
>>> > To: arocket@xxxxxxxxxxxxx
>>> > > > If you have photons leaving in significant numbers you will have
>>> at least
>>> > some thrust; but that's a conventional photon rocket. Photon rockets
>>> give
>>> > very small thrust and are highly inefficient; it turns out that almost
>>> all
>>> > the energy leaves with the photons and hardly any ends up accelerating
>>> the
>>> > vehicle. (It's due to the extreme mismatch between the exhaust speed
>>> and
>>> > vehicle speed, you always want the two to be about the same-ish
>>> relative to
>>> > the launch frame of reference aka inertial reference frame.)
>>> > > Note that these thrusters have no photons leaving other than thermal
>>> ones
>>> > due to waste heat; they consist of sealed cavities filled with
>>> microwaves. > They claim that by quantum/relativistic/magic/somehow
>>> they will start
>>> > moving all by themselves. > > I'll only really believe it if it floats
>>> up into the sky and yanks the
>>> > power cord out of the wall. > > > On 3 August 2014 09:23, Steen Eiler
>>> Jørgensen<steen@xxxxxxxxxxx> wrote:
>>> > > > Den 03-08-2014 02:09, Ian Woollard skrev:
>>> > >
>>> > > > There's essentially no chance that a thruster can work where you
>>> turn
>>> > > > it on, feeding only electricity through it, and with nothing
>>> leaving
>>> > > > it; where you switch it off, and you're now moving faster. This is
>>> > > > what the emdrive is claimed to do. > >
>>> > > Please define "nothing". Photons (e.g.) have no mass, but nonzero
>>> momentum. > >
>>> > > /steen
>>> > >
>>> > >
>>> > >
>>> > > > -- > -Ian Woollard
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>
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