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Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Soul Surfer on 08/09/2006 11:15:59

Title: An anti gravity machine for real!?
Post by: Soul Surfer on 08/09/2006 11:15:59
This week's New Scientist has got an article in it about a new electromagnetic drive for spacecraft that could be much more efficent than the currently being tested ion motors.  

It is so way out that I double checked the date wasn't  1st April

It has been dsigned and tested and found to work by   Roger Shawyer a respected aerospace scierntist at Portsmouth University.

Apparantly the idea has been around for some time but it is the way that it works is so far off beam I still find it difficult to believe and am looking for the catch.

You feed microwave radiation into a high Q resonant cavity that is shaped.  The shape is a tapered cylindrical waveguide with one end greater than the other and the idea is to get as much energy stored in the cavity that you possibly can.  He is feeding about a kilowatt into a cavity with a Q in the region of 6,000 - 50,000.

The enegy in the cavity produces a force on the cavity along its axis and in the direction of the largest end.  He explains it as the enegy in the cavity produces a force on the walls of the cavity and the force is greater on the wider end than the narrow end so there is a net external force on the cavity.  Note, no throwing energy out the back like a rocket! the energy is entirely contained in the cavity and the force depends on how much you can get in there.

OK the force is not very great, his first prototype only produced a force of 16 millinewtons but a later model with a higher q gave 300 millinewtons,  a great deal more thrust than that produced by the recent ESA SMART-1 Ion engine.

It is claimed that in theory using a superconducting cavity of the quality used in big accelerators forces of  30,000 newtons per Kilowatt might be achieved. this is enough to lift a car!

The downside.  You are not getting something for nothing and the moment you start accelerating the object the force drops and energy is drawn from the cavity and needs to be replaced  but the device could produce a static anti gravity force very efficiently.

This is the nearest thing to an antigravity machine I have ever seen and is coming from a very reputable scientific source but I am still finding it difficult to believe.


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Title: Re: An anti gravity machine for real!?
Post by: Nieuwenhove on 08/09/2006 12:03:10
I can't believe it either. I guess that waves are somehow escaping from the device.
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 08/09/2006 15:23:20
No they are not for the cavity to have a very high Q all significant losses must be reduced to an absolute mininmum and I guess the only way for EM radiation to get out of the cavity will be via the input waveguide which will probably have a special coupler to prevent this.

I think that I understand how it could work but I am still amazed that the opposing effects do not balance.  

Electromagnetic radiation posesses no mass but it does posess momentum and this is well known and can be measured.  Inside a waveguide cavity the radiation goes backwards and forwards between the two ends.  the Q factor gives a measure of how many times it can do this before the energy is lost.  The assymetrical design of the cavity means that the group velocity of the radiation in one direction is different from the group velocity in the other  this difference in group velocities means that there is a slight momentum imbalance between the waves travelling in one direction and the waves travelling in the other  this is seen as an attempt for the cavity as a whole to gain momentum,  which if this is prevented, appears as a force.  If the body is free to move it will gain momentum but as it does it will accelerate and energy will be taken out of the cavity and must be restored to keep the force acting  so the laws of conservation of energy and momenum are not being violated.

What amazes me is that it is apparently possible to make this assymetric cavity.  I would have expected things to have balanced themselves out.

THe existence of this process makes me wonder if there are any particle physics situations when this may happen and if so, this may have important consequences in our understanding of dark matter, dark energy and inflation.

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Title: Re: An anti gravity machine for real!?
Post by: thebrain13 on 09/09/2006 04:12:52
soul surfer, you said that once it accelerates it loses its energy, so doesnt that mean that it would lose its energy in the presene of a gravitational field, even if it is stationary relative to a ground observer?
Title: Re: An anti gravity machine for real!?
Post by: bostjan on 10/09/2006 01:59:03
My E/M professor in grad school told me I was foolish when I asked him about the possibility of harnessing E/M momentum to make a sort of ion engine.  But then, he also told me that there was no future in ion engines.

If this thing really works, it is a true breakthrough for the possibilities in space travel.  Not that anyone seems to get nearly as excited about space travel as we do.
Title: Re: An anti gravity machine for real!?
Post by: science_guy on 11/09/2006 15:59:37
that would make sense.

two reasons that people arent excited about space travel:
      1)many people dont believe in aliens
      2)many people dont want to pay more taxes on what may become useless missions.

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Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 11/09/2006 23:26:37
No I believe that it would not lose energy if the object is not accelerating in its own frame of reference and that includes hovering in a gravitational field if it can produce enough thrust to support its own weight.  mind you looking at the numbers it is unlikely that a device could be built to achieve this in earth's gravity. however if you compare its performance wit that of ion engine thrusters for spacecraft it could easily be much more efficient and it uses no consumable fuels to generate the thrust.  All you need is electrical energy  and you can get that from solar cells or a thermal isotope source.  It might even be the route to a practical starship design.  

It is important to note that such an engine would not be detectable from any great distance because it profuces no visible or particle radiation.  If aliens were using more converntional rockets or ion motors for getting around using large ships they would be detectable at very long ranges.

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Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 07:42:13
I'm sorry, Soul Surfer, but I can't understand the physical principles of this effect. Nothing escapes from the cavity? Are you sure there can be a force on it? It seems impossible to me. Explain what you know about it.
Title: Re: An anti gravity machine for real!?
Post by: Nieuwenhove on 12/09/2006 09:15:25
Hi Soul Surfer,

I couldn't find the article you mentioned in New Scientist. Could you please indicate the issue (date) and page number ?
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 11:40:04
Momentum must conservate: if the device gain momentum in a direction, something else must gain momentum in the opposite direction and this is impossible if there is no energy or particles flying back.
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 12:05:49
quote:
Originally posted by bostjan

My E/M professor in grad school told me I was foolish when I asked him about the possibility of harnessing E/M momentum to make a sort of ion engine.
I don't understand the connection between E/M momentum and ion engine; however, of course is very simple to use E/M momentum to make an engine: a powerful laser beam directed back (photon engine). The force on the space-ship is W/c where W is the laser (or whatever light source) power in Watts and c the speed of light. For a 1 Megawatt laser, the thrust is about 3300 N (= 340 Kgf).
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 12/09/2006 13:49:41
I find this figure rather high when the designers of space vehicles speak of using sails in the order of square kilometers to propel their vehicles by sunlight which I understand has a power of about 1.3 KW per sqare meter.
Is there a different calculation for photons. bouncing of a surface as against locally generated ones. 10^6/3*10^8 = 0.00333 what units are employed ? or did you use a million megawatt laser.

syhprum
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 14:43:30
quote:
Originally posted by syhprum

I find this figure rather high when the designers of space vehicles speak of using sails in the order of square kilometers to propel their vehicles by sunlight which I understand has a power of about 1.3 KW per sqare meter.
Is there a different calculation for photons. bouncing of a surface as against locally generated ones. 10^6/3*10^8 = 0.00333 what units are employed ? or did you use a million megawatt laser.

You are right, I'm sorry. I was thinking "Terawatt" and for some misterious reason I wrote "Megawatt"! (Can someone solve this mistery? Mah!)
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 12/09/2006 16:03:42
The NewScientist article quotes the case of a light sail of 600 square meters which would adsorb about 1 MW of sunlight and producing 0.0033N force

syhprum
Title: Re: An anti gravity machine for real!?
Post by: bostjan on 12/09/2006 18:42:11
E/M waves carry linear momentum proportional to Poynting's vector, even in static fields.

Think about if you put an electron with finite mass in an e/m field.  It accelerates, and thus gains momentum, but where does the momentum come from?  It comes from the field.  Pretty cool, I think.
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 19:13:20
quote:
Originally posted by bostjan

E/M waves carry linear momentum proportional to Poynting's vector, even in static fields.

Think about if you put an electron with finite mass in an e/m field.  It accelerates, and thus gains momentum, but where does the momentum come from?  It comes from the field.  Pretty cool, I think.

Yes, and what generate the field? Other electric charges that acquire a momentum in the opposite direction.
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 12/09/2006 19:18:53
quote:
Originally posted by syhprum

The NewScientist article quotes the case of a light sail of 600 square meters which would adsorb about 1 MW of sunlight and producing 0.0033N force
Exactly. With 1 Terawatt (= 10^12 Watt = 1000 Gigawatt = 1000,000 Megawatt) you have 3300N.
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 12/09/2006 19:51:56
The new sciemtist article is on pages 30 - 34 of the 9 September issue.

Re conservation of momentum  I agree and find it difficult to believe that this will work but there seems to be strong evidence that it does.  Let me try to explain again.  Photons do not have mass but they do have momentum  In the tapered waveguide cavity the group velocity of the photons moving in one direction is different from the group velocity in the other direction this means that there is a net imbalance in the  momentum imparted on the two ends of the cavity.  Apparrantly the cavity with the largest end has the biggest momentum (This would tie in with waveguide theory where the group velocity in a larger waveguide is higher than that in a smaller waveguide)  so if the obgect is free to move this imbalanced momentum is transferred to the whole object and it can accelerate.  

This force is vaguely  related to the much talked of casimir effect,

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Title: Re: An anti gravity machine for real!?
Post by: syhprum on 12/09/2006 20:29:43

Light arrow

I see the possibility for a school lab demonstration here a one watt laser could be fitted to the bottom of a one meter pendulum enclosed in a vacuum jar so that it has a very large 'Q' factor and the laser pulsed a the resonant frequency of the pendulum.
1 watt would give a force of 1/(3*10^8) Newton's but if you had enough patience you would eventually get it swinging.

Although a 1 Megawatt laser is just about at the bounds of present day technology I don't think one with a continuous output of 1 TW is possible

syhprum
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 12/09/2006 23:16:17
I do not think that you could create the required assymetric group velocity very easily at optical frequencies. It is far better to use microwave frequencies and 1 kw magnetrons are dirt cheap and reliable (standard microwave oven kit)

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Title: Re: An anti gravity machine for real!?
Post by: bostjan on 13/09/2006 01:52:34
quote:
Originally posted by lightarrow

quote:
Originally posted by bostjan

E/M waves carry linear momentum proportional to Poynting's vector, even in static fields.

Think about if you put an electron with finite mass in an e/m field.  It accelerates, and thus gains momentum, but where does the momentum come from?  It comes from the field.  Pretty cool, I think.

Yes, and what generate the field? Other electric charges that acquire a momentum in the opposite direction.



Consider two identical isolated charges, riveted on tracks perpendicular to each other.  Say these charges are pushed towards each other from a far distance, with the same speed.  As they approach, it is easy to see that the electrostatic forces repel each other, thus they are equal and opposite, but what about the magnetic forces?

Due to their movement, their magnetic fields are equal and opposite, but the magnetic forces are not.  (Use right hand rule if you wish)  How can this be?  Momentum must be stored in the fields.
Title: Re: An anti gravity machine for real!?
Post by: thebrain13 on 13/09/2006 02:40:18
Soul surfer, given the equivalence principle, there is no difference between an accelerating object in outer space, or an object in a gravitional field, granted the acceleration is equal. So if it would lose energy accelerating somewhere, away from anything in outerspace at 9.8 m/s^2. It would lose the same amount of energy resting on the surface of the earth, or if it was "floating" not moving relative to a ground observer.
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 13/09/2006 06:25:14
quote:
Originally posted by bostjan

Due to their movement, their magnetic fields are equal and opposite, but the magnetic forces are not.  (Use right hand rule if you wish)  How can this be?  Momentum must be stored in the fields.
Ok but "the fields" means electromagnetic radiation = photons; if the total momentum and angular momentum of the charges doesn't conserve, it's because photons are released in such a way that the total momentum and angular momentum (charges + photons) always conservate.
If the cavity doesn't send photons away of it (laser, maser or anything else), it's very difficult for me to believe in its effective functioning.
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 13/09/2006 07:40:13
re photon propelled spacecraft

Considering the mass of the associated power generating eequiptment I do not think there is any future in photon propelled space ships although a very low mass sail might just about work close to a star for instance to propell a vehicle from earth to the Kuiper belt.
Pity about the 'Tera' 'Mega' mix up it would work fine if we could use megawatts.

syhprum
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 13/09/2006 08:03:09
quote:
Originally posted by syhprum

re photon propelled spacecraft

Considering the mass of the associated power generating eequiptment I do not think there is any future in photon propelled space ships although a very low mass sail might just about work close to a star for instance to propell a vehicle from earth to the Kuiper belt.
Pity about the 'Tera' 'Mega' mix up it would work fine if we could use megawatts.
Of course at the moment Terawatt lasers are Very havy, but laser-maser technology is improving. In the future, photon engines should be the best choice for long travels, in my opinion, because you don't have to throw away any mass, so you can keep the engine on for as long as you want (providing that you have energy, of course).
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 13/09/2006 09:56:56
Sorry Brain  I expressed myself badly there I was not suggesting any violation of the equivalence principle if the thing could be powerful enough to lift a body of the surface of the earth (which I very much doubt)  It would of course be accelerating at one g even when it is hovering  I was only thinking about the extra losses associated with moving the mass of the unit upwards.

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Title: Re: An anti gravity machine for real!?
Post by: syhprum on 13/09/2006 11:04:30
Re photon drives

I must really disagree the largest mobile power sources that we have are the nuclear power units in submarines, these are certainly less than 100 megawatts electrical probably more like ten and cannot be run for more than a year or two without major maintenance.
To drive a terawatt laser (if such a thing could be created ) they would have to be scaled up by a factor of 10^7 at the very least , made maintenance free for hundreds of years for interstellar travel with no great increase in mass.
I do not think this is just a matter of technological development I consider it impossible!.
Let me see a calculation of the probable mass of a photon drive ship travelling to the nearest known star with a planetary system and what leap in power generation technology would be required

syhprum
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 13/09/2006 15:02:36
quote:
Originally posted by syhprum

Re photon drives

I must really disagree the largest mobile power sources that we have are the nuclear power units in submarines, these are certainly less than 100 megawatts electrical probably more like ten and cannot be run for more than a year or two without major maintenance.
To drive a terawatt laser (if such a thing could be created ) they would have to be scaled up by a factor of 10^7 at the very least , made maintenance free for hundreds of years for interstellar travel with no great increase in mass.
I do not think this is just a matter of technological development I consider it impossible!.
Let me see a calculation of the probable mass of a photon drive ship travelling to the nearest known star with a planetary system and what leap in power generation technology would be required

syhprum

Yes, it's still not possible to make a Terawatt laser with continuous emission, as you pointed out, but what is impossible now will remain impossible in the future? I'm not talking about just some years.

Anyway, it's not even necessary to have a laser (or maser) for a photon engine: you could heat a body to high temperatures (heated with any kind of energy you want, included matter-antimatter reaction) to make it radiate light (and/or infrared radiation) and so have a thrust.
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 14/09/2006 00:32:16
If I place a small magnet above a superconducting sheet it remains elevated despite gravity without the expenditure of any energy.
Yet if I wish to do the same with Roger Shawyer's anti gravity machine I am told that a continuous supply of energy is required, wherein lies the difference?.


syhprum
Title: Re: An anti gravity machine for real!?
Post by: thebrain13 on 14/09/2006 01:36:51
your magnet pushes down on the superconducter, which balances everything out. The anti-grav machine doesnt push on anything.
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 14/09/2006 07:11:52
I deserve to have one brownie point deducted!, and I have lectured people on action and reaction on this board.

syhprum
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 14/09/2006 12:11:08
I have been doing a bit more thinking about how this machine would work (if it does work of course)  and what it would be useful for.  Here are some further thoughts and notes.

The amount of momentum ( ? static force) that you can generate depends on the Q of the cavity  a very high Q cavity can generate a lot with relatively low power input but the moment it starts to move, energy will be lost and the Q of the cavity will fall and so will the momentum that it produces.

The new scientist article suggests and tries to illustrate that this has causes a 1kw unit mounted horizontally on an air bearing causing the unit to rotate  at up to 20rpm although I note that the article did not say uambiguously that it actually did do this when the author saw it  he only said that it should spin and there was a blurred photograph of the apparatus in motion as well as a clear picture of the stationary apparatus which looked quite plausible.

The waveguide is a circular one  and is probably a TE100 very low loss overmoded waveguide to up the Q  (must look up group velocities and sizes)

I can easily accept that the momentum transfer to the wide end is greater than the narrow end but would expect that there would also be some momentum transfer to the tapered section that would balance things out and result in a zero net thrust.

We are not familiar with slow momentum transfer dynamics and think more in terms of forces and impulsive momentum transfers(like billiard balls hitting each other) and I am still trying to het my mind around how it works in a gravitational field.

Consider an object stationary and sitting on top of a balance pan that is weighing it by using a load cell that has a miniscule deviation to register. As I increase the power of the upwards momentum I would expect the object to weigh less and it appears that this has been demonstrated  with the first device producing 16 millinewtons using 1 KW of electrical power (magnetrons are quite efficient at converting electrical energy into microwaves).

If the cavity had a very high Q and there was lots of power available it might in theory be able to reduce the apparent weight to zero.  Now how does this reconcile with the equivalence principle stated above because the energy being used is apparantly much less than that required to accelerate the mass at 1g.  The only answer  I can see is that it is because we are talking about a momentum transfer and not a force  the equivalent acceleration is associated with the microwave photons that are "accelerating"  (their group velocity is increasing in the expanding waveguide as they move upwards in the cavity and strike the top face) what then happens if I try to move it upwards?  well the cavity loses efficiency and the apparant force to accelerate the object increases so the object is a bit harder to accelerate than I expect but it should still accelerate and continue to do so while I apply the force and in every way obey newtons laws of motion.  This does really seem to be like an anti gravity machine!

But what about the corresponding deceleration of the photons as they move downwards?  doesn't that counteract the acceleration?  well photons are massless and the acceleration and decelleration is only associated with the shape of their "universe"  (the cavity) and does not require any energy  (very weird!)

Again this always depends on the effect working and I am still very skeptical because it seems too much like something for nothing (or very little)

Mind you I have seen an "electromagnetic" related theory of gravitiation some years ago  (from a chap named Jennison I think from Kent university)that has some similar features to this suggesting that gravitation was just a residual "van der walls" type force resulting from the geometrical dynamics of electrical forces inside  particles atoms and of course dark matter.  If that was the case, it might be possible to produce an anti gravitational force by using energetically assymetric dynamics of electromagnetic waves.

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Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 14/09/2006 12:32:50
Whatever could be the functioning, if the cavity is closed, isolated and doesn't interact with other external systems/bodies and doesn't emit particles/photons/energy, it's impossible it can receive a thrust, without violating the most basic physical laws.

When you say: "The only answer I can see is that it is because we are talking about a momentum transfer and not a force", I don't understand it, since they are the same thing: dp/dt = F.
Title: Re: An anti gravity machine for real!?
Post by: alexb on 14/09/2006 14:11:30
The thing that troubles me about this is the described demonstration.

Horizontally mounted to one side of a vertical axis air bearing, the demo will provide horizontal thrust to set the equipment spinning.

But we don’t need microwaves and relativity in the box to do that.  Just a vertical axis gyroscope.

Now I'm not suggesting that My Shawyer would do that.  But perhaps he should know better than to expect to demonstrate his kit in a rotational situation.

After all, we are told in the article that he used to work for Sperry Gyroscope.

I’ll not be investing my pennies just yet a while.
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 14/09/2006 18:34:10
I notice that the PSU is mounted on air bearing alongside the anti-gravity device, it is quite possible the a verticaly mounted fan in this could cause a gyroscopic effect not to mention any effect from expelled air.

syhprum
Title: Re: An anti gravity machine for real!?
Post by: Nieuwenhove on 15/09/2006 17:35:12
I finally was able to read this article. The explanation offered in the article is very short and very poor. Apparently, it should be related to some kind of relativistic effect which defies are intuition. Nevertheless, I do not understand sentences like "Since the microwave photons in the waveguide are travelling close to the speed of light, any attempt to resolve the forces they generate must take account of Einsteins special theory of relativity. This says that the microwaves move in their own frame of reference. In other words they move independent of the cavity - as if they are outside" And that's it ! Although I'm familiar with relativity, this really means nothing to me. Can anyone reformulate this in more scientific language ? If the machine really works (unlikely), the inescapable conclusion would be (for me) that one has demonstrated the existence of an aether and that this aether has taken up the opposite momentum.
And what would be the fate of this moving aether ?
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 15/09/2006 19:14:50
I am begining to believe that this is just a money making scam, like cold fusion, homopathy, or the various magic water and Ice tales that we hear.

syhprum
Title: Re: An anti gravity machine for real!?
Post by: Nieuwenhove on 17/09/2006 17:00:57
quote:
Originally posted by syhprum

I am begining to believe that this is just a money making scam, like cold fusion, homopathy, or the various magic water and Ice tales that we hear.

syhprum


Since I'm still doubting about the feasibility of the electromagnetic drive I checked again what special relativity says about this. Acoording to special relativity, it is clear that momentum should be conserved and hence the drive can not work. On the other hand, one could also argue that one should use general relativity since the microwaves bounce of the walls (exerting pressure) and thus accelerate (changing direction). In general relativty however, momentum itself is not strictly defined (" Momentum is the Noether charge of translational invariance. As such, even fields as well as other things can have momentum, not just particles. However, in curved spacetime which is not asymptotically Minkowski, momentum isn't defined at all." ; see http://dictionary.laborlawtalk.com/Momentum) and thus there might be an opening here for some kind of non-conservation of momentum. Any comments ?
Title: Re: An anti gravity machine for real!?
Post by: bostjan on 18/09/2006 03:26:48
Oh, I can't believe that I missed the part about no energy coming out.  This is certainly impossible.  If the microwaves leave the cavity, it should be possible to generate a thrust without loss of mass, though.  I now understand the confusion over my statements.  Acceleration without expendature of energy violates more than just Newton's laws.
Title: Re: An anti gravity machine for real!?
Post by: Nieuwenhove on 17/09/2006 17:00:57
quote:
Originally posted by syhprum

I am begining to believe that this is just a money making scam, like cold fusion, homopathy, or the various magic water and Ice tales that we hear.

syhprum


Since I'm still doubting about the feasibility of the electromagnetic drive I checked again what special relativity says about this. Acoording to special relativity, it is clear that momentum should be conserved and hence the drive can not work. On the other hand, one could also argue that one should use general relativity since the microwaves bounce of the walls (exerting pressure) and thus accelerate (changing direction). In general relativty however, momentum itself is not strictly defined (" Momentum is the Noether charge of translational invariance. As such, even fields as well as other things can have momentum, not just particles. However, in curved spacetime which is not asymptotically Minkowski, momentum isn't defined at all." ; see http://dictionary.laborlawtalk.com/Momentum) and thus there might be an opening here for some kind of non-conservation of momentum. Any comments ?
Title: Re: An anti gravity machine for real!?
Post by: bostjan on 18/09/2006 03:26:48
Oh, I can't believe that I missed the part about no energy coming out.  This is certainly impossible.  If the microwaves leave the cavity, it should be possible to generate a thrust without loss of mass, though.  I now understand the confusion over my statements.  Acceleration without expendature of energy violates more than just Newton's laws.
Title: Re: An anti gravity machine for real!?
Post by: dgdavisjr on 22/10/2006 02:41:37
quote:
Originally posted by syhprum

I deserve to have one brownie point deducted!, and I have lectured people on action and reaction on this board.

syhprum


Actually you tripped over a glaring, yet continually overlooked violation of the physical laws of thermodynamics and conservation of energy. According to these laws energy cannot be created or desroyed but only converted to another form. Where does the energy that the mgnetic disk is supported by come from? Why can't it be exhausted? Like magnetic poles will oppose each other without diminishment of power level. How? The energy must (according to known law) come frome somewhere but it seems to be inexhaustable and free. Try a lecture on this.

D.G.Davis,Jr.
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 22/10/2006 10:30:30
quote:
Originally posted by Nieuwenhove

Acoording to special relativity, it is clear that momentum should be conserved and hence the drive can not work. On the other hand, one could also argue that one should use general relativity since the microwaves bounce of the walls (exerting pressure) and thus accelerate (changing direction). In general relativty however, momentum itself is not strictly defined (" Momentum is the Noether charge of translational invariance. As such, even fields as well as other things can have momentum, not just particles. However, in curved spacetime which is not asymptotically Minkowski, momentum isn't defined at all." ; see http://dictionary.laborlawtalk.com/Momentum) and thus there might be an opening here for some kind of non-conservation of momentum. Any comments ?
So we should have already seen momentum conservation violations every time light is reflected by a mirror, isnt'it?
Title: Re: An anti gravity machine for real!?
Post by: Soul Surfer on 22/10/2006 11:34:23
No, there is a force on the mirror as it reflects light.

The small magnets floating over a superconducting surface work because the surface is superconducting  and the normal eddy currents that form a a magnet approaches a conducting surface do not die away.   I have seen this happen in the lab where I worked.  as soon as the superconductor warms up a bit ans the superconductivity goes awy the magnet fall on to the surface.

I am now almost certain that this reactionless drive cannot possibly work because the designer is not taking into account the foreces on the tapered section of the waveguide.  The forces on the two ends of the cavity are clearly different but there is also a momentum transfer on the tapered section and the elements of the force in the direction of the smaller surface together with the force on the smaller surface and effective momentum change must balance out the force on the large surface.

Learn, create, test and tell
evolution rules in all things
God says so!
Title: Re: An anti gravity machine for real!?
Post by: syhprum on 22/10/2006 13:12:49
This was day one in physics when I was at school, the fact that a force exists does not immply that energy is generated or adsorbed it is only when there is movement against a force that energy comes into play ( we used to talk about it in foot pounds in the old days! )

syhprum
Title: Re: An anti gravity machine for real!?
Post by: lightarrow on 23/10/2006 13:47:24
quote:
Originally posted by Soul Surfer

No, there is a force on the mirror as it reflects light.
Yes, of course there is a force, and so?
quote:
...the designer is not taking into account the foreces on the tapered section of the waveguide.
It means that designer didn't even study high school physics!