Let me get this right
If you shoot microwaves at people's houses you can float overhead with less energy.
Sounds like it would be popular even if it were real...
A controversial British antigravity device is to be investigated by the government's National Space Centre, according to reports. If the technology really works, it would be able to counteract the force of gravity using only electrical power, permitting the easy building of Jetsons-style flying cars or hoverships and hugely …
"violates the conservation of momentum"
Existing "standard" physics states clearly that this device cannot work. But, curiously, the theoretical arguments advanced by Shawyer, don't include any new physics, just a somewhat confused calculation based on standard physics. Anyone want to spot the contradiction?
And, quite frankly, if you are going head-to-head against conservation of momentum and Einstein's theory of relativity, then you have to perform better than that video. What was it? Box hanging from a wire swings and/or rotates slowly?
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Maybe not, but it makes a perfectly good crystal ball. Here's what it says about the future.
1) Emdrive is tested under rigorous scientific conditions and found to be a complete load of bollocks.
2) All funding is withdrawn, the inventor's branded a charlatan and his lovingly accrued accreditions are revoked.
3) The nuttier ends of the blogosphere (ugh) explode in an orgy of conspiracy theories as to how this technology is being suppressed by Big Oil / Big Government / The Military / The Illuminati / Alien sponges from the planet Thrarb / Mrs Johnson from No. 24 / whatever.
4) The Mythbusters build one from a set of "build your own antigravity machine" plans bought for $25 off eBay and prove it doesn't work.
5) Repeat 3.
6) etc. ad infinitum
7) Six million years later, a superintelligent radioactive mutant cockroach invents a microwave antigravity machine............
where people actually believe this crap?
I'm just assuming that Dr Costella is wrong and the guy is just deluded not a thieving con artist like the banking system that generates wealth until it needs to steal from the taxpayer just when it looked like it was going so well...
Take a conical styrofoam cup.
Put a sealed lid on it.
Does the cup now float?
There is quite a lot of air bouncing around inside that cup, quite fast - exactly the same as his microwaves, but with considerably more momentum because they have a lot of mass.
If you want to check further, get a sensitive set of scales and find out if the weight of the cup and lid changes with the lid fitted or removed.
As opposed to the light driven space crash that don't have a reaction mass? They are simply driven by the pressure from a light?
You do understand that you can weigh light by shining on weighing scales? And they call it 'radiation thrust' or some such, so as not to have to give up the idea of photons having no mass.
So yes there are charlatans here, but not necessarily the ones you are thinking of.
"He says that the thrust drops off rapidly once the generator starts moving along the line of thrust".
Moving relative to what? The spinning, orbiting Earth going round the sun which goes round the galaxy which moves relative to other galaxies?
@mmiied, re "even if there is a 1 if 33billion chance"
That means that we would need to test Thirty Three Billion crackpot devices to find one which worked. Scientists have better and far more productive things to do! Or would you like to try to persuade the various governments to tie up all the scientific resources of the entire planet for years to come "just in case"?
"He says that the thrust drops off rapidly once the generator starts moving along the line of thrust"
So, he claims that he has falsified Newtownian physics and relativistic physics.
Of couse, you can always get off the planet real fast by stopping. Just make sure you know what direction the planet is headed first.
Note that there ARE propulsion systems that don't have reaction mass in the conventional sense. The closest one would use magnetic effects to push against the Earth's magnetic field.
I have a flying sausage that can travel through time and eradicate poverty and hunger. It's only in design stage at the moment, but i calculate a 1 in 32 billion chance that it will work. It will cost £50 million to investigate.
When can i expect my check from you?
PS. I have an O level in Sausology, so am more than qualified!
The earth used to be flat, and at the center of the universe...
I'm quite convinced he's wrong, as seems to be the consensus of everyone else, but people used to think the earth was the center of the universe, until Copernicus came along, and that the earth was flat'ish, until Magellan circumnavigated it*.
Terribly arrogant to just say "He's wrong, because we don't believe him" - we've made mistakes in the past about physics, are undoubtedly making loads now, and will make even more in the future.
* OK - it was known to be spherical (ish) before that, but he is the guy who conclusively proved it, even though he was dead by the end of the voyage...
Though you could argue the Greeks proved it, or the Egyptians.
This is not pseudo science, it sounds exactly like the laser power space craft:
There is nothing special about light that doesn't apply to other forms of electromagnetic radiation. It sounds like wave pressure, as for violating the laws of 'conservation of momentum'.... oh good grief, are we in kindergarden?
"Shawyer throws relativity into his paper, if only because he really can’t avoid it for a particle that moves at the speed of light (well, is light, or its cousin, anyway). Maybe some weird spooky relativ-istic effect makes Shawyer’s scam drive work?"
Fascinating bunch of comments above, the commentards are out in force, armed with a smattering of physics, a huge dose of arrogance, and a near inability to actually read the story.. specially the ones who are claiming he's a zero-point energy nut.
That's not what I read, whatever claims he's making, this is a net consumer of energy, not a provider. He's basically saying he can apply energy to a chamber and generate a thrust. His special claim is that there is no reaction medium (either thrust against the atmosphere, other objects, or ejected matter) specifically he seems to say it thrusts against the gravitational field itself. I don't see that as physically impossible, just technically impossible until now?
As for the people complaining they cannot see 'under' the test rig.. read the article..sheesh.. where it is clearly stated that the rig is on an air bearing. His thrust unit is angled to rotate the rig on that bearing, not lift it.
(This would be thrusting 'across' gravity, not 'along' it; so I'm not convinced the effect is real; but I am convinced a lot of posters here are applying some barely remembered schoolboy physics and repetition of mantras against perpetual motion to dismiss it with no real understanding of what is actually being claimed.)
Maybe I'm just too fond of the skyhooks that Rupert the Bears professor friend used to make. The thing is that there is a field, the gravitational field, that ruins through most everything. If we can find new ways to interact with that that we should be able to make some interesting devices.
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Shawler claims an _improvement_ over ordinary light pressure -- by the Q factor of the cavity! Naturally if Q is high, you get more supposed "Shawler thrust", ... but high Q means that hardly any light escapes to provide actual thrust. The force exerted will in fact reduce as Q increases.
Columbus knew the earth was round. He even knew that he couldn't get to the spice islands by going the route that Cabot took cos he knew America was in the way - we'd been fishing the Newfoundland cod banks since 1480.
It only seems to be politicians and managers and others that run things that know jack.
If the guy can get it 10 foot off the ground outside then it might be worth looking at to see how the con worked.
Till then it might be worth teaching some newtonian physics to people who handle taxpayers money - transfer of momentum to the arse for idiots who fund this sort of thing.
It seems that someone has been reading some old (1950s and early 1960s) H. Beam Piper sci-fi. Piper's 'countragravity' worked something like what this guy says he has, only as Piper was writing fiction in the days before Star Trek he had to at least try to make his techno-speak hang together semi-plausibly. The ships in Piper's stories about the Federation appear to have been better thought out than that 'demonstration video' thing. After all, Piper _was_ writing for John Campbell at Astounding, and Campbell was notorious for wanting to see the rivets on the hulls of the spaceships before he bought the story. (Campbell would have bounced most of the stories put on the air in Star Trek, for example. Not least for the outrageous biology behind Spock...)
On the other hand, Campbell _was_ a big supporter of the Dean Drive, which this also somewhat resembles and which also didn't work. IIRC Lee Corey perpetuated a Dean Drive story or two a few years after Campbell's death. It wasn't nearly as well received without Campbell there to push it. I expect that this 'device' will go tits-up RSN.
There must be at least 5,000 ways to achieve a visual effect like that. There must be at least 50 ways to get a piece of kit to actually hover like that appears to. Have any of them proved to be of any use at all? Well, we do have mag-lev trains. Are they of any use at all? Er... Should we ignore it? No, we should not. It's like being given a lottery ticket that appears to have the winning numbers on it. It probably looks too good to be true because it is. On the other hand, wouldn't you feel a right wally if it was genuine and you sent them packing? What? Cold fusion? Yeah, I know...
"If you actually read the article, it isn't the same thing at all. It heats air and causes thrust, which of course is not at all the same thing."
Radiation thrust is a PROVED, DEMONSTRATED thing, yes I know it's not Newtonian, but lots of physics isn't. Just because some bloke called Newton said he made laws, and they teach them as simplified physics, doesn't mean they are actually laws! They were just simplifications that were easy to teach to students!
I may have not found the right article that discusses it, but it's long been considered in space travel (as distinct from the solar sail probes).
"You don't have to have mass to have momentum"
Again, really, this is nothing special, the effect is called Radiation Thrust or some such. Yes I know light has no mass ergo it has no momentum, ergo it has no pressure, but it does and is measured and accepted.
IMHO, light is waves in matter, the proof that light has zero mass is simply not there, they just put in energy to accelerate particles, found they couldn't accelerate something with mass to the speed of light hence, some conclusion was jumped to, their theory was 'proven', and an awful lot of drivel has been built ontop of that since.
That aside, an electromagnetic wave causing pressure on objects is not new or special. It doesn't mean it's the effect he's using, just that what Mr Debunker is saying strikes me as baby physics (conservation of momentum as a law FFS) and hence not a debunking more a troll.
"he seems to say it thrusts against the gravitational field itself."
No he doesn't!
"He says that the thrust drops off rapidly once the generator starts moving along the line of thrust, so that the kit would really only be of much use to nullify an opposing force - for instance that of gravity."
He makes no statement that indicates his machine has any kind of interaction with the gravitational field, only that it could nullify the force of gravity (in the same sense that the force of gravity can be nullified by the effect of buoyancy in a balloon).
Whatever the effect of his device, it's obviously such a tiny force (at the moment) that it can only move the device under low friction conditions (hence the air table). But what's to prevent other tiny forces giving the same effect? For example, the device could be just rotating in the Earth's magnetic field. It will take some carefully designed experiments to prove or disprove the effect being claimed.
This guy sounds worse than legendary scam kiddie Edward Jenner. Edward claimed that cow milkmaids never got smallpox ; having got simple cowpox it later protected them somehow from the more deadly smallpox. After eventually dreaming up a ludicrously stupid "smallpox inoculation derived from milkmaids" this master con-man side-stepped years of ridicule and cartoons lampooning him with a cow's head etc. Until errr finally someone noticed he was right and was single-handedly responsible for the only time in history mankind has completely eradicated a killer disease. You lot are going to look a bit daft if the anti-grav bloke does come up good.
Tom 7 wrote:
"Columbus knew the earth was round. He even knew that he couldn't get to the spice islands by going the route that Cabot took cos he knew America was in the way - we'd been fishing the Newfoundland cod banks since 1480."
And the Vikings had been to Newfoundland as well. Columbus knew that, too. Oh, and the whole "everyone in the Middle Ages thought the world was flat" stuff has been shown to be a fallacy: the classical civilisations believed the world to be round and this knowledge didn't just go away, nor was it particularly ignored, apparently.
Of course, the whole "world is flat, Columbus shows otherwise - how daring!" business is just propaganda sold to the Ameritards, along with the "Thomas Edison invented everything" bollocks that gets paraded out to "inspire" American juniors. Just as the Britards have their own national myths, so do the Ameritards.
he's not claiming it as the basis of a warp drive or anything like that vectored-momentum thing that crops up every so often.
And just thrusting against the Earth's gravitational field with another field doesn't sound particularly impossible- interaction of fields is the basis of tech like the electric motor, transformers, generators and a load of other stuff the world wouldn't work without.
It's also been shown that gravity can affect microwaves, radiowaves, light and other EM radiation Every slightly nerdy schoolkid has seen the rubber sheet and billiard ball explanation of spacetime, with light bending around stars and so on.
So if it's redirecting them and having other effects on them why shouldn't they be able to push back?
I'm not 100% sure about the actual physics- I'm an engineer not a theoretical physicist- but it certainly doesn't sound impossible to me.
I've just started a No.10 petition demanding that if this works it should be fitted to a DMC DeLorean for its first public showing... I'll post the link if/when it gets approved.
@AC 1636 the Biefield-Brown effect has been proven and has even been put into practical vehicles- the Japanese even made an EHD boat.
Accelerating charged particles with a high voltage is even in secondary school physics. Yes, it's been proven. But no, it's not antigravity- that's a frequently debunked (even on dedicated "lifter" sites) myth that probably came about by some marketing guy selling plans.
the flamewar wasn't confined to their comments pages, being a reaction to a cover article about the EmDrive. The vast majority of correspondents, in line with the vast majority of physicists and engineers (and Greg Egan), concluded that the whole thing is a load of bollocks unworthy of discussion in any journal hoping to be considered as having firm scientific credentials.
My goodness, what an astounding video! They have made a device that, without human intervention, TURNS BY ITSELF. (Yes, I am being sarcastic BTW.)
I wonder what function the oscilloscope provides, that is so vitally essential to this turning action that it has to be mounted on the turning portion of the contraption.
This would be much more convincing if it were shot on blurry VHS video.
Dr. Costella pointed out his fundamental error in assuming that the force on the sides of the chamber acts perpendicularly to the axis of the chamber, when it actually acts perpendicularly to the surface. First-year physics students would catch that mistake. (The latest version of the paper makes no mention of these forces, but still neglects to account for them properly.) Shawyer digs his hole deeper by claiming the force produced depends on velocity. This implies that there is a single 'correct' frame of reference, and that measurements taken from all other frames of reference are invalid, which violates the fundamental tenets of physics. I'm sure he'd claim the 'correct' frame is that of a stationary (relative to the ground) person, which implies a geocentric universe, and that idea got debunked a long time ago.
I was about to say this is bad science, but it's actually just bad engineering. It does have aspects of bad science: the measured effects are barely perceptible, and criticisms are countered with apparently ad-hoc excuses. (See Langmuir's Laws).
@ACs 14:56, 15:52 :
Light-powered spacecraft are not closed systems. The force of the laser beam on the spacecraft has a corresponding force against the Earth in the other direction; momentum is conserved. You can't make a laser-powered craft that carries its own laser.
A gravitational field is not a tangible object that force can be applied to. Same with magnetic and electric fields. You can apply a force to the magnet or electric charge, but not the field itself. It's *stated* that the device is on an air bearing, but no actual evidence of that is given. The way it rotates around a fixed axis suggests a physical connection between the device and table.
And the most damning flaw: According to his paper, the net force on the assembly is in the direction of the larger end. The device in the video is turning the *wrong way*!
You're quoting events from pre-scientific times. Yes "science" has, on rare occasions, been wrong about something. but the scientific process is self correcting; through experimental evidence and peer review, science is able get back on track. Mainly though, physics has seen a succession of theories that have only added small "corrections" to earlier theories, or explained the experimental evidence to a better degree of accuracy.
For example, Newtonian mechanics is fine for describing every human vehicle ever made (the Pioneer 11 space probe reached 107,000 mph), we'll only need to use Einstein's relativistic mechanics when we can move at 10% of the speed of light, which is about 630 times faster than Pioneer 11, even then Newton is only "wrong" by 1% .
Whatever physical effect this guy has managed to produce, the explanation is not going to require a rewrite of the current laws of physics; there's just too much evidence that confirms the current models, and too little evidence in the film to indicate that anything contrary to current knowledge of physics is happening.
"even if there is a 1 if 33billion chance he is right it is worth looking into if he is right it could be world changing"
Not with my bloody tax-money they shouldn't.
At least - not without *SOME* form of bloody proof. GRRRR. Idiot scumbags the lot of 'em.
Flogging would be too good for em......
moan, grumble, moan.........
Ignorance is bliss, perhaps?
NASA have also researched the Biefield-Brown and Mythbusters also aired a program on this.
NASA lists it as an IONIC wind device, so it won't work in a vacuum.
For anyone with an interest, go to youtube and search for "lifter antigravity" and you'll see some interesting backyard videos of quite a number of people who have built working protoypes. In the US, there are a number of school fairs and science expos that have demonstrated the principle. Google "Biefield-Brown" and you'll see a number of academics showcasing their work for school projects..
In their current state, they show limited use, but more R&D could be put into refining the technology.
Uusally when antigravity devices come up for discussion, the objection is on the grounds of conservation of energy. The classic example is H. G. Wells' Cavorite, which, if it existed, would enable you to get an infinite supply of energy. Covorite was a substance which shielded against gravity...so you could cover a mass, let it float up, uncover and let it fall, getting free energy, and repeating the cycle indefinitely. While this would be nice, it would definitely not be conserving energy, and since this principle is well established, it would appear to be very unlikley that a substance like Cavorite could actually exist.
That does not necessarily preclude the existance of something that would fit the description of antigravity, yet would also comply with the principle of conservation of energy. So what would be the characteristics of such a device? Well, experience tells us we will not get something for nothing, so it is probably going to cost us some energy to keep the device running. So while it is running, we would expect such a device to somehow overcome the local gravitational attraction, so that instead of falling it remains where it is as long as it is working. Now, staying in one place is not all that useful, so we would also like to be able to have the device raise itself, and lower itself, under control. When it raises itself it will have gained gravitational potential energy, so we must expect to have to put in an equivalent amount of energy, plus a bit more since few things are 100% efficient. Conversely when it lowers itself energy will become available, and we may even with luck be able to recover some of it.
So far we have just described a helicopter, an aeroplane, or even a lift for that matter. So the next thing is that our hypothetical antigravity machine must be able to accomplish all of this without a physical connection to the ground (or any other fixed object), without using reaction mass, and without requiring an atmosphere around it. you cdan accomplish things a bit like this with a good strong magnetic or electrostatic field, but what we would really like is to be able to do this a long way from any other fixed object, so that for instance we could start off on the ground, rise straight up into the air, and reach earth orbit. The actual orbit would also require us to accelerate sideways of course, but we would naturally be happy to feed in the energy needed to do this.
The interesting thing is that if you work out the energy to do this, for say a useful size of space capsule, it is not all that high. If the actual cost of the energy were the only barrier to space flight, we would already have commerce around the solar system. Sadly, we don't know how to make such an antigravity device, and I see no particular reason to beleive that the device referred to in the article represents any sort of step towards this. Ity would be nice, but just because some sort of device would be nice does not mean that it is actually possible to build one.
I mean come on how rich is the Catholic Church or Scientology or the Mormon Church. People want to believe something that others like them also do and are willing to contribute it if helps them get through the day with a purpose I suppose. As long as I am not taxed for others beliefs (grr stupid Navy keeps funding cold fusion) so be it.
"I have a flying sausage that can travel through time and eradicate poverty and hunger. It's only in design stage at the moment, but i calculate a 1 in 32 billion chance that it will work. It will cost £50 million to investigate."
As far as I know government research programs, if you ensure the consultants that do the feasibility study get the work you should be getting your grant relatively easy. After all, it worked for ID Cards..
Lord Kelvin said flight was impossible yet the Wright Brothers managed it. Just one of many , many examples where arrogant professors assume that if they don't know something then it just can't be possible. The laws of thermodynamics were developed after the heat engines had already been built; the physicists then cheekily stealing them and calling them laws of physics and then trying to apply them to other areas where they often don't apply.
It wasn't that long ago that the Bernoulli effect was described universally in text books as the one and only reason why wings cause lift. That turned out to be simplistic and wrong and it was then replaced by other theories which were also wrong. All theories were only small portions of a very complex 3d fluid flow mechanism. Yet at one time if you built a wing that you said defies Bernoulli, (which is perfectly possible) yet still works you'd have been called a charlatan, despite the fact that pilots who flew upside down were defying Bernoulli too.
I recently read up about cold fusion. From the denouncements of eminent scientists you'd think that the original experiment hadn't been replicated. In fact in experiment after experiment it has been replicated, and in each case the arrogant establishment who have a vested interest in hot fusion tell us that the experiment must have been in experimental error, for this, that or the next reason that they just pulled out of their arses. Cold fusion though since it demonstrably happens is still being investigated by governments because at the end of the day science is about studying the odd things that happen in nature and trying to account for them. Those who assume something won't work despite mounting evidence that it does are the real charlatans.
Now that means it's this simple: It either works or it doesn't! No amount of professorial hubris will ever impress an engineer. When Physicists can explain whether light is a wave or a particle, or explain what the hell is dark matter, dark energy, or reconcile the Big Bang with the laws of physics (for which they conveniently overlook) then they can pontificate with some respect. Meantime engineers will continue to build things by largely ignoring Physics professors. As Von Karman put it: “The Scientist studies what is, the engineer creates what has never been.” Unfortunately too many scientists don't even do that, preferring instead to fit their data around their implacable dogmata.
I think 3 people have already mentioned Costella. Unfortunately, Costella manages to be all of patronising, irritiating, and wrong. He says that Shawyer ignores forces perpendicular to the wall. That's not actually the error here - Shawyer is free to decompose the force any way he wants, as long as he does it on 2 perpendicular axes, and he chooses the x and y axes. The problem is actually that he ignores the x contribution along the tapering section of the waveguide. He assumes that all the (lateral, x-axis) forces are derived from the thrust on the two end plates; he ignores the fact that the radiation impacting on the narrowing waveguide also gives a lateral thrust to the right. In short, the two endplates are effectively the same size, so no thrust. It's no more complicated than that.
Which leads me on to Costella's second oversight. He thinks that Shawyer brings in relativity "if only because he can't avoid it for a particle that moves at the speed of light". Not quite; Shawyer has a much more important reason. He knows that his result makes no sense for a closed system, and he has to get around this problem somehow. Look at Shawyer's figure 2.1 - it's obvious that in this *open* system excess photons leave to the right, so there's a net thrust to the left. Shawyer knows that his closed waveguide doesn't look like this, so how does he get around the problem? If it's a closed system, it won't move, period.
Shawyer has a simple rationalisation. He says that his *closed* waveguide is actually an *open* system *because* of relativity. However, this is just plain wrong; search for the four occurrences of the word 'open' in his theory paper. He says "Relativity theory implies that the electromagnetic wave and the waveguide assembly form an open system", and "The second effect is that as the beam velocities are not directly dependent on any velocity of the waveguide, the beam and waveguide form an open system", and so on. He doesn't justify this in any way, and I'm afraid that it's just wrong. The relativistic stuff (pages 7-14) is irrelevant. He constructs an imaginary system in which an object generates a force to move itself, and shows that, in the frame of reference of a "stationary" observer, this force reduces to zero as the speed of the object approaches the speed of light. That's basically just a statement of the obvious. This, by the way, is why Shawyer says that this apparatus becomes less efficient as it gets faster.
Which brings me on to Smart awards. Shawyer funded this on a Smart award, and Costella gets hot under the collar about this. Smart awards are meant to fund off-the-wall stuff; I can't complain, as I've had one myself. However, this case does show (some of) the failings of the system. The DTI is (was?) meant to get a sanity check on applications before giving away money. This would never have got through any competent sanity check; any Physics undergrad should have spotted these problems in 10 minutes.
Original "theory paper": www.newscientist.com/data/images/ns/av/shawyertheory.pdf
Costella's response: http://www.assassinationscience.com/johncostella/shawyerfraud.pdf
I know pretty much bugger all about the theory behind all this, but best of luck to him.
Many times in history a massive advance is ushered in by a brilliant crackpot like this that won't accept the text books. Maybe this is one of those times, maybe not, maybe all it needs is a really, extremely hot cup of tea!
I like your comment, but have one point to make re: no net thrust (I'm not saying there *would* be net thrust...)
"he ignores the fact that the radiation impacting on the narrowing waveguide also gives a lateral thrust to the right. In short, the two endplates are effectively the same size, so no thrust"
I thought the same thing - if you view either end in 2d you'd see the same size target. However, a proportion of the narrow end isn't "as perpendicular" (for want of a much better phrase) to the wave as the end plate. Throw Pythagorus at it and you should see a slightly lower rightward thrust due to this (i.e. the photons "glancing" off the narrowing section).
I still struggle to understand how photons that are reflected and retain the same energy content can produce any thrust - you're creating energy. However, that's probably why nobody pays me to do physics :)
The perpendicular/angle/Pythagoras thingy is tricky. To do it properly, you have to solve for the geometry of the waveguide, knowing the trajectories of the photons.
There is one limiting case where it's obvious that the geometry isn't important. In this case, the photon emitter is a flat surface in the Y axis, towards the large end (left) of the waveguide. It blasts photons out to the left and right, along the X axis. Most of the ones travelling to the right hit the sloping wall of the waveguide. In this case, there is no Y component to the photon momentum, all the momentum goes along the X axis, and there's no net left/right force.
Anything else is much more complicated. To solve these cases for a conical waveguide, you would define an annular ring in the Y axis, where the edge of the ring has height dy, calculate the force along the X axis against this dy ring, and integrate along the length of the cone. The fundamental insight here is that we use the same dy anywhere along the length of the cone.
Since dy is the same for all our rings, dx must vary depending on the precise geometry of the cone at that point on the X axis. In other words, we have a little triangle, with photons entering along the hypotenuse, and we need to calculate the force normal to the dy side (along X). You're right that Pythagoras says that only a proportion of the force goes to the right, but the insight is that the hypotenuse is longer than dy, so more photons than 'necessary' enter the triangle, and it all balances out when you take the X component of these extra photons. This isn't obvious, but consider the simple case where dx and dy are the same (the wall is 45 degrees at this point), and the photons enter perpendicular to the hypotenuse. In this simple case, all the root 2's cancel, and it's exactly the same as "viewing either end in 2D" as you put it.
Ok, a general proof is impossible because it depends on the location and geometry of the photon source, the geometry of the waveguide, extra reflections, and so on. In any event, this is the wrong way to do it - the right way is to solve for the fields inside the waveguide, and find the forces at the boundaries.
Shawyer hasn't done any of this. He didn't attempt any particle-like force calculations along the sloping walls, and he didn't attempt to solve for the fields, so his force calculations are incorrect. In any event, it's unnecessary to solve anything if you accept that the waveguide is a closed system. All the actions and reactions inside balance out, so there's no net movement. He glosses over this bit by saying that Special Relativity "implies" that the system isn't closed, without stating in what way it isn't closed. He has to demonstrate that there's a matter or energy transfer in or out of the waveguide to make it an open system, and he completely omits to say what this transfer is. And, of course, he only invokes special relativity *after* his derivation of the net force imbalance; he can hardly use it to justify his result.
> I still struggle to understand how photons that are reflected and retain the same
> energy content can produce any thrust - you're creating energy. However, that's
> probably why nobody pays me to do physics :)
There is a general conception that photons only transfer energy in an absorption process (and not in reflection or transmission). I don't understand where this comes from - maybe a pre-quantum view? When a photon strikes a surface and transfers momentum via radiation pressure, momentum is conserved, but this doesn't mean that there's no energy transfer. If the surface it strikes is free to move (a solar sail, for example) it takes on twice the momentum of the photon, and must therefore take some of its energy. The photon reflects with a longer wavelength to take account of the lost energy. In this case, the waveguide doesn't move, but some energy will be transferred to the waveguide surface, and the photon will again lose energy.
..is that the Universe sucks. Nothing fun works, and everything that does work is hard.
Where's the anti-gravity devices, the time machines, the warp drives, the matter transporters? They're what make the future interesting. We need to be drafting some new laws of physics, here.
Guys! You are criticizing and judging an authority figure and known scientist, without giveing him the benefit of the doubt! This is exactly what happened to all great theories starting Galileo Galilee and even Einstein's relativity theory at first.
And by the way, the arguments brought by Dr John Costella to call him a crackpot are are childish at best!. He comes with his 6th grade physics and conservation momentum, but forgets to get up to date with 2nd year coledge physics. It's widely known that the energy and momentum of a radiation wave depends on its frequency or equivalently, its wavelength. You DO NOT NEED MASS to have momentum.
the momentum p = h * (2*PI/wavelength),
where h is the reduced Plank constant.
Stop saying it's bs until the whole thing is checked out. Physics sais it's possible, lets see if he did it or not.
Who are you to judge him?
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