[AR] Re: NASA test of quantum vacuum plasma thruster (was "Anyone heard of this?")
- From: Keith Henson <hkeithhenson@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Wed, 6 Aug 2014 14:05:21 -0700
On Wed, Aug 6, 2014 at 12:59 PM, <qbert@xxxxxxxxxxxxxxx> wrote:
> Where and why do you guys keep on coming up with perpetual motion? It is
> stated quite clearly that it requires electric power to operate. While it
> does not require a stored fuel in the true sense of the word, it still
> requires power to run and the tests so far show that much more energy is
> need than the equivocal thrust produced. So if all of that is the case where
> is the perpetual motion.
You don't seem to be familiar with the thought experiment that makes a
drive of this type into an energy source.
Mount such a drive on a frictionless skate board in a vacuum. Turn it
on and the device will accelerate while using a constant amount of
power. When it reaches a high enough speed, lower a wheel connected
to a generator. At some speed, the generator output will equal the
constant power the drive is using. At any higher speeds, it is making
"free" power.
Keith
> Robert
>
>
> At 12:33 PM 8/6/2014, you wrote:
>>
>> On 06/08/14 14:47, Keith Henson wrote:
>>>
>>> On Wed, Aug 6, 2014 at 1:41 AM, Peter Fairbrother <zenadsl6186@xxxxxxxxx>
>>> wrote:
>>>>
>>>> On 06/08/14 05:47, Troy Prideaux wrote:
>>>>>
>>>>>
>>>>> As we've concluded here many times in the past, rockets don't care
>>>>> how fast they're going with respect for the surroundings. More energy
>>>>> or more Isp per given mass ratio = better performance as per the
>>>>> rocket equation. It does matter a lot with air breathing propulsion,
>>>>> but not with rockets or for that matter the technology of current
>>>>> discussion.
>>>>
>>>>
>>>> I think maybe it does matter with this technology - if it doesn't then
>>>> it
>>>> would be a perpetual motion machine, and even less likely to work.
>>>
>>>
>>> Then the laws of physics, at least as they apply to this technology,
>>> would have to be variable depending on velocity. Then the question
>>> becomes velocity with respect to *what*?
>>
>>
>> What indeed, which is where the previous conversations about
>> Michelson-Morley, Lorentz invariance, and so on come in.
>>
>> Purely from an informational point of view (ie, looking at how does the
>> drive know what the velocity zero is, while ignoring how it interacts with
>> it), as far as I can see there are at most two possibilities.
>>
>> The first and in my opinion by far the most likely (but only because the
>> other is even less likely!) possibility is zero velocity relative to the big
>> bang; which is also a zero relative to the mass in and/or of the universe;
>> and for practical purposes is very close indeed to the rest frame relative
>> to the cosmic microwave background.
>>
>> The last is something which we can actually measure; we are travelling at
>> 369±0.9 km/s in the direction of galactic longitude l = 263.99±0.14°, b =
>> 48.26±0.03 relative to that rest frame.
>>
>>
>>
>> The second possibility comes from General Relativity and is sort of
>> similar in terms of being a summation of the effects of all the mass in the
>> universe, but it takes local matter more into account. For various reasons I
>> think it's very unlikely indeed but I thought I'd mention it as, like the
>> rest of these speculations, it is not impossible, assuming the rest of
>> physics is correct but incomplete.
>>
>>
>>>
>>> I was amused by a comment on a recent discussion of power satellites
>>> about how this would make transporting the parts to GEO easier. If
>>> this is real, it's the future energy source, forget power satellites.
>>
>>
>>
>> Yep.
>>
>> Unless of course it does vary depending on velocity ... in which case it
>> isn't a perpetual motion machine, and is somewhat less implausible.
>>
>> -- Peter Fairbrother
>>
>>
>>>
>>> Keith
>>>
>>>> -- Peter Fairbrother
>>>
>>>
>>
>
>
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