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[P]
Maxwell's thermodynamic daemon realized ?

By chro57 in Science
Tue Jun 28, 2005 at 04:34:06 AM EST
Tags: Science (all tags)
Science

Maxwell's demon is a theoretical device able to bypass the second law of thermodynamics, allowing anyone to produce unlimited free energy with the device. Until now, it has always been possible to prove theoretically that they couldn't be constructed, or would fail to function.

This "badly published" article presents a version of Maxwell's demon for which there is currently no published theoretical proof of unworkability, and the author pretends to have built and tested it. If there are no flaws, then the invention is an industrial revolution waiting to happen.

However, as is, it may as well be an elaborated joke. But where is the theorical flaw? There are no obvious flaws in the design itself.


The device built by Xin Yong Fu consists of two cold cathodes in a vacuum tube, and a magnet. There is a flow of electrons from one electrode to the other due to thermoionic emission and one way deviation by the magnetic field. The result is a very tiny current out of the electrodes, and Fu theorizes the extraction of energy from a single source of heat.

If you do try to find the flaw: don't say that the energy is extracted from the tearing of the magnet. This is not a good argument. And arguing that the device won't work due to the second law of thermodynamics is simply circular logic.

On the funny side, it's remarkable that the author didn't try to get a patent, simply because there China lacks a system for patenting scientific inventions. By contrast, there are tons of incomprehensible patents for free energy devices. Let's not forget all of the legends of secrets from governments' agencies and oil lobbies. There are also at least four dubious US startups pretending to have secret free energy technologies and perpetually looking for money, but they usually end up as a scam.

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Poll
is it possible to bypass the second law of thermodynamic ?
o Yes. It's just our current knowledge. 13%
o No. Because this is the law. 26%
o Only in another universe 22%
o Only by the grace of God. 11%
o The device is hidden in Area 51 with the flying saucer. 26%

Votes: 68
Results | Other Polls

Related Links
o Maxwell's demon
o the second law of thermodynamics
o free energy
o This "badly published" article
o thermoioni c
o free energy devices
o Also by chro57


Display: Sort:
Maxwell's thermodynamic daemon realized ? | 133 comments (122 topical, 11 editorial, 0 hidden)
WIPO: Unknown /nt (1.33 / 3) (#2)
by Dont Fear The Reaper on Sun Jun 26, 2005 at 04:41:23 PM EST



Just take a look at who's voting how. (1.66 / 3) (#3)
by alby on Sun Jun 26, 2005 at 04:46:20 PM EST

Speaks for itself.

--
Alby

Even if this works (2.20 / 5) (#4)
by LilDebbie on Sun Jun 26, 2005 at 05:01:42 PM EST

it's still drawing energy from the ambient air temperature, thereby not creating free energy but merely converting ambient heat.

Oh, and -1, k5 is not the place for peer review.

My name is LilDebbie and I have a garden.
- hugin -

the SECOND law of thermodynamics (none / 1) (#8)
by dhall on Sun Jun 26, 2005 at 05:29:43 PM EST

There is energy everywhere in heat, but the second law says that you can't extract some of it.

To extract energy from heat, you need to move heat energy to a colder place, and even then you can only get a fraction out as useful work.

To simply convert ambient heat into work means you're decreasing the entropy of the universe.

[ Parent ]

No (none / 0) (#34)
by LilDebbie on Sun Jun 26, 2005 at 11:58:12 PM EST

One can convert ambient heat into work by only decreasing local entropy, increasing it elsewhere.

My name is LilDebbie and I have a garden.
- hugin -

[ Parent ]
but (none / 0) (#36)
by dhall on Mon Jun 27, 2005 at 12:09:45 AM EST

I did say 'simply'. Of course I knew someone was going to point out bla bla bla bla you get what I'm saing.

[ Parent ]
Missing the point (3.00 / 2) (#12)
by ElMiguel on Sun Jun 26, 2005 at 05:40:38 PM EST

it's still drawing energy from the ambient air temperature, thereby not creating free energy but merely converting ambient heat.

You missed the point completely. Nobody said this was violating the conservation of energy, or creating new energy from nothing.

The article speaks about "free energy" for a different reason. You know, when you use energy (say from a battery) the energy is not destroyed, as that would be violate conservation of energy also. Instead the energy becomes degraded so it cannot be used again; usually, it goes into the ambient in the form of heat.

The second law of thermodynamics states that the global amount of energy degradation ("entropy") cannot be decreased. If it could, the energy problem could be solved simply by using the same energy over and over again; hence the talk about "free energy".

Oh, and -1, k5 is not the place for peer review.

Why not? K5 is a place for discussion and peer review can produce much more interesting discussion than the millionth article about American politics.

[ Parent ]

Okay (none / 0) (#35)
by LilDebbie on Mon Jun 27, 2005 at 12:02:31 AM EST

But why does the article employ terms such as "free energy" and "Maxwell's demon" then? Also, we already have the technology to convert ambient heat into work, therefore this won't be of any interest until it can produce a significant amount of work efficiently. The article is pandering to bullshit, pseudo-science pipe dreams when all that's been generated is a new spin on an inductive generator.

Finally, peer review has that pesky first term, which I think maybe five people here could seriously make claim to in scientific criticism.

My name is LilDebbie and I have a garden.
- hugin -

[ Parent ]
Well (none / 0) (#69)
by trane on Mon Jun 27, 2005 at 06:22:23 PM EST

Finally, peer review has that pesky first term, which I think maybe five people here could seriously make claim to in scientific criticism.

That should become obvious by the content of the comment. Instead of having to rely on ad hominems and appeals to authority.

[ Parent ]

No we don't. (none / 0) (#90)
by Fon2d2 on Tue Jun 28, 2005 at 11:51:39 AM EST

We have the technology to convert heat differentials to work. We do this usually by heating water to produce steam to turn a turbin.

In a room where everything is at the same temperature, there is no heat differential to exploit. In a power plant this would be manifested in one of two ways:

1. The water is already heated, because the entire plant is at a superhot temperature, thus there is already only steam, and no liquid water to heat into steam to create the necessary pressure.

2. The entire plant, including water is at room temperature, and there is no heat source applied to the water to convert it to steam since you are trying to use "ambiant heat" instead of the energy contained within the oil or coal or whatever you should be using.

[ Parent ]

Why couldn't you... (none / 0) (#130)
by StangDriver on Thu Jul 14, 2005 at 03:07:36 PM EST

...use part of the energy resulting from the turbine to power a cooling compartment?

[ Parent ]
That's the second law of thermodynamics. (none / 1) (#131)
by glor on Mon Jul 18, 2005 at 01:59:53 PM EST

The cooling is necessarily inefficient.  Cooling can make your energy extraction more efficient, but only up to a limit (called the "Carnot limit").  

This discussion has become slow enough that my advice is to look in a book if you want more details.  But using energy from a heat gradient to increase the heat gradient is exactly what the second law claims is impossible.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

Crap (2.00 / 5) (#5)
by manobes on Sun Jun 26, 2005 at 05:25:50 PM EST

But where is the theorical flaw?

It violates the second law of thermodynamics, that's the flaw.

HTH

HAND

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


aren't you interested in learning? (none / 0) (#10)
by dhall on Sun Jun 26, 2005 at 05:33:23 PM EST

I think it's interesting to look at the physical reasons for why it doesn't work.

Sure you could probably use a general proof of second law, but it's good to look at things from more than one angle.

[ Parent ]

I'll wager that (none / 0) (#13)
by manobes on Sun Jun 26, 2005 at 05:42:56 PM EST

I've forgotten more physics than you've ever learned.

I think it's interesting to look at the physical reasons for why it doesn't work.

I think it's more interesting to learn about actual unsolved problems in physics. But hey, what do I know about physics?

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
dot dot dot (none / 1) (#14)
by dhall on Sun Jun 26, 2005 at 06:00:48 PM EST

I don't know how much you know. I only know how much I know. Sort of.

If you're asked why the sky is blue, do you say "Because of quantum mechanics."?

I think that anything I learn from thinking about the question in this article will be far more practical than understanding all your research. (burn)

[ Parent ]

Indeed (none / 0) (#126)
by Winkhorst on Fri Jul 01, 2005 at 08:37:52 PM EST

The real problem with his kind of thinking is that it assumes its conclusion. I am reminded of Lavoisier's "proof" of the nonexistence of meteorites: "There are no rocks in the sky. Therefore, rocks cannot fall from the sky." To use a scientific "law" to disprove the existence of contrary evidence is disengenuous at best, and just plain stupid at the worst.
______ *****Welcome to Avalon*****
[ Parent ]
Er, (3.00 / 3) (#16)
by ElMiguel on Sun Jun 26, 2005 at 06:11:31 PM EST

I know the physics in the article must be faulty. I don't need an accomplished physicist to point that out. What I'm looking for is an explanation on *why* the article is mistaken. Do you think you could get down from your high throne of physics for a minute to help with that? For the enlightenment of the masses, you know.

[ Parent ]

beat me to it. iawtp. -nt (none / 0) (#18)
by Kasreyn on Sun Jun 26, 2005 at 06:17:42 PM EST

nt
"Extenuating circumstance to be mentioned on Judgement Day:
We never asked to be born in the first place."

R.I.P. Kurt. You will be missed.
[ Parent ]
Umm (none / 0) (#20)
by manobes on Sun Jun 26, 2005 at 06:26:16 PM EST

Do you think you could get down from your high throne of physics for a minute to help with that?

Sure!

It violates the second law of thermodynamics, like I said. It's a macroscopic system, so it can't do that. Pouring over the fine details isn't going to teach anybody much physics at all.

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
The fine details... (none / 0) (#22)
by ElMiguel on Sun Jun 26, 2005 at 06:34:19 PM EST

Pouring over the fine details isn't going to teach anybody much physics at all.

Seriously, I don't see why not. I'm not asking for formal proof, just some sort of general explanation of for, example, what would be the final equilibrium, could potentially be interesting.

[ Parent ]

Not everyone can be Richard Feynman. (none / 1) (#26)
by Lanes Inexplicably Closed to Traffic on Sun Jun 26, 2005 at 07:30:17 PM EST

The man was an exceptional teacher precisely for the reason that most people professionally involved with physics are grumpy and arrogant like this fellow.

[ Parent ]
All of the fine details (none / 0) (#28)
by ubernostrum on Sun Jun 26, 2005 at 10:02:38 PM EST

Are readily available. Just go sign up for some physics courses at your local community college.




--
You cooin' with my bird?
[ Parent ]
You are a stupid asshole (none / 1) (#37)
by JosiahGibbs on Mon Jun 27, 2005 at 01:09:31 AM EST

Physics, like any science, relies on dialectical reasoning. You obviously don't know what that is, preferring to argue by insults and appeal to authority. I don't care if you know F=MA or the wavefunctions of a one-electron atom, you don't know shit about physics because you don't know the principles of natural philosophy it is based on, so don't be telling people to learn shit when you don't know shit yourself.

[ Parent ]
Hm, (none / 0) (#60)
by ElMiguel on Mon Jun 27, 2005 at 04:14:12 PM EST

What is so bad about you know, trying to have some discussion in a discussion site? Yes, this story is taking up valuable queue space that could be used for another story on Iraq or the Bush administration or talking broccoli, but I'm sure K5 will survive anyhow.

[ Parent ]
Not every opinion is valid (none / 1) (#64)
by kero on Mon Jun 27, 2005 at 04:46:06 PM EST

It may be true that this paper has discovered something that will create a paradigm shift in physics as we know it. But that's not the way professionals would bet. Something this remarkable requires remarkable evidence which it doesn't have so it's pretty understandable why someone who knows physics isn't that interested in trying to have a "discussion" about it. At this point it would be a waste of time, like aruging that the sun isn't going to come up tomorrow. Sometimes a crackpot idea is a new paradigm waiting to happen, but most of the time it is just a crackpot idea.

[ Parent ]
No question about that (none / 0) (#66)
by ElMiguel on Mon Jun 27, 2005 at 05:05:42 PM EST

As far as I can see, nobody is questioning that the paper must be wrong, for the reasons you've pointed out. Also, nobody is holding a gun to manobes's or anyone else's head; if they feel this discussion is a waste of their time they're free not to comment.

What I think some of the critics in this article are failing to notice is that finding the flaw in a faulty exposition can provide for interesting discussion and learning opportunities. Most high school math books I've seen included some fake proof that 2=1, so the student could test his knowledge by trying to find the incorrect step in the proof.

[ Parent ]

Vol 1, Chapt 46: Ratchet and pawl (3.00 / 2) (#25)
by Alan Crowe on Sun Jun 26, 2005 at 07:17:25 PM EST

Feynman spends nine pages of his lectures on physics pouring over the fine details of the ratchet and pawl "perpetual motion machine". He obviously thought that explaining why it didn't work would teach his undergraduates physics.

Unfortunately reading the chapter only adds to my confusion. He gives a time reversal argument.

This means that if we have a certain motion, then the exact opposite motion is also possible.
How do I apply this to an electron traversing a magnetic field? When I send it back the other way doesn't the field deflect it to right instead of the left?



[ Parent ]
Time reversal (none / 0) (#53)
by rpresser on Mon Jun 27, 2005 at 12:31:09 PM EST

If you time-reverse an electron, it behaves as a positron, hence it retraces the same path (curves in the opposite sense when time-reversed)
------------
"In terms of both hyperbolic overreaching and eventual wrongness, the Permanent [Republican] Majority has set a new, and truly difficult to beat, standard." --rusty
[ Parent ]
B -> -B (none / 0) (#68)
by doru on Mon Jun 27, 2005 at 05:21:04 PM EST

The magnetic field changes sign under time reversal! An intuitive way of seeing it is by considering the field generated by charges running around in a loop. Time reversal requires reversing the velocities of all bodies in your system, including these charges.

Hope that helps.


I see Rusty's creation of Scoop as being as world changing an event as the fall of the Berlin wall. - Alan Crowe
[ Parent ]

Hmm (2.66 / 3) (#33)
by trhurler on Sun Jun 26, 2005 at 11:55:07 PM EST

If you're going to keep falling back on an argument which, when definitions are substituted for the terms they define, reads as "previous observations say this is wrong, so it must be wrong, even if you observe it," please just take your advanced degrees and go home. You can always say "I don't know why, but I don't believe it will work." You can always say "I can't be bothered." That's an ok answer. On the other hand, "This is wrong because famous people said so on the basis of their observations," when applied to an observation, is complete nonsense. Period.

I personally think what's going on is twofold. I think the magnet is supplying the energy(which is on a much smaller scale than the magnet's field strength anyway,) and that if you wait long enough, the magnet will become nonmagnetic and the system will fail. I think attempts to grow this system to provide enough energy to care about would fail, and that the energy required to create the magnets would always be greater than the energy the system put out over time. Having said that, I'm a mile ahead of your useless ass, however many degrees you have, because my argument makes sense and yours amounts to "I know better than you, so please shut up."

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
Not drawing energy from the magnet (none / 0) (#48)
by Alan Crowe on Mon Jun 27, 2005 at 06:59:15 AM EST

The magnet is pushing the electrons at right angles to their direction of travel. Since the direction in which the force acts is orthogonal to the direction in which the particle moves, no work is done.

If energy is being drawn from the magnet, it is vanishing. This violates the First law of thermodynamics. This hypothesis is a more dramatic violation of physical law than the device it is aiming to refute, which merely violates the Second Law of Thermodynamics.



[ Parent ]
Hmm (none / 0) (#78)
by trhurler on Mon Jun 27, 2005 at 08:42:17 PM EST

If the magnet is pushing them and they aren't moving, where is the energy needed to push them going? You want to say "back to the magnet," but you know this isn't true; magnets don't last forever. Moreover, if the magnet is ONLY pushing them perfectly perpendicularly, then it is totally unnecessary for the setup to work. Yes, magnetism does affect electrically charged particles perpendicularly to its own field, but that doesn't mean the magnet in this system is placed such that it isn't moving the particles. I suspect it is in fact moving the particles, or else it wouldn't be there. The resulting energy is not disappearing - it is the current flow observed.

Of course, nobody has yet proven(aside from one allegation that hasn't been confirmed,) that this device in fact produces a current flow at all. For all I know, it doesn't. But if it does, this is how I'm betting it works.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
bzzt (none / 1) (#85)
by rpresser on Tue Jun 28, 2005 at 07:28:39 AM EST

If the magnet is pushing them and they aren't moving,

If they aren't moving, the magnet isn't pushing them. A static magnetic field only acts on a charged particle moving in a direction with a component perpendicular to the field. Stationary particles don't even know it's there.
------------
"In terms of both hyperbolic overreaching and eventual wrongness, the Permanent [Republican] Majority has set a new, and truly difficult to beat, standard." --rusty
[ Parent ]

Think of it this way... (none / 1) (#89)
by Fon2d2 on Tue Jun 28, 2005 at 11:43:41 AM EST

Without the magnet, the electrons would just fly off in a straight line. But the magnet makes them move in a circular motion, since it always applies a force orthogonal to the direction the electron is traveling. This is like a ball on the end of a string. The ball would go straight, except for the string. With the string, the ball will continually move in a circle because the string is always applying a force perpendicular to the direction the ball is moving towards the central axis. However, it should be obvious in this situation the ball is not consuming energy produced by the string. It has the same energy at all times (excluding friction) and the string's presence or absence has nothing to do with that. Also, when the ball is at rest, the string is applying no force. This is a direct analogy for the electron and the magnet.

[ Parent ]
Magnetic fields and energy. (3.00 / 2) (#102)
by glor on Tue Jun 28, 2005 at 05:17:36 PM EST

A static magnetic field changes a (structureless, charged) particle's trajectory without changing its energy.  A _changing_ magnetic field can do work, but that's not what's claimed here.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

You are a butthole (1.66 / 3) (#38)
by JosiahGibbs on Mon Jun 27, 2005 at 01:13:29 AM EST

Physics, like any science, relies on dialectical reasoning. You obviously don't know what that is, preferring to argue by generalizations and appeal to authority. I don't care if you have published 300,000 papers, you don't know shit about writing about physics because you don't know how to explain it in terms that will change the mind of an interested nonspecialist.

[ Parent ]
Sir. (3.00 / 5) (#57)
by ubernostrum on Mon Jun 27, 2005 at 01:41:36 PM EST

(a + b^n)/n = x, hence God exists. Reply!




--
You cooin' with my bird?
[ Parent ]
Manobes, please read this. (2.60 / 5) (#39)
by sudog on Mon Jun 27, 2005 at 01:34:21 AM EST

You're wasting your time arguing with them. They're trying to draw you out into explaining, in basically what will amount to detail so fine they can no longer understand it, precisely what is (or is not, as the case may be,) happening, and thereby save them the effort of going out and learning it on their own.

They're just using the fact that they spend more time here than you do (and can therefore take the time to pick you apart with pedantics) to achieve one of two purposes:

1. They get to feel superior when you give the appearance of bowing out, thinking that that is proof they were somehow right and you were wrong. This is why they will never stop responding to you. Ever. They seem to equate the "last word" with "righteousness."

2. In case you do write something large and argumentatively irrefutable, they hope to learn something that they can then turn around and use in future arguments with other people, so they can again feel superior.

In effect, they're knowledge thieves, or at least petty knowledge thugs, because the moment you do give them something valuable they'll hoard it like treasure and wield it as a weapon against everyone else.

As I see it, you have two basic choices.

You can state you recognise them for who they are in a note (and thereby rob them of their prize) and stop wasting your time here on K5. After all, none of the ones trying to draw you out will ever appreciate the effort you go to, and any selfless attempt to educate them will be twisted into something which will do damage in the general populace as they parrot your words as their own from their shoddy little thrones.

Or, of course, you can go ahead and make them feel stupid, and yourself feel superior, and use them as whipping boys. In that case, just get down to quick of the matter and do it, and stop teasing the rest of us with the delicious promise of their inevitable humiliation.


[ Parent ]

+1,FP puzzle stumps highly qualified professional (2.33 / 3) (#21)
by Alan Crowe on Sun Jun 26, 2005 at 06:28:32 PM EST

If some-one of Nobes professional standing is reduced to harrumphing and pulling rank, that is convincing proof that the flaw in this Maxwell's Demon is subtle enough to be interesting and educational.

I wish I knew what the flaw was :-(



[ Parent ]
Somebody of my "professional standing" (3.00 / 2) (#51)
by manobes on Mon Jun 27, 2005 at 08:32:15 AM EST

expects to read professional papers. There's a reason for that, since in a non-professional paper, you can't tell anything about anything.

You'll notice the authors have no discussion of any potential systematic errors, there are no error bars, despite the fact that the measured currents are close to the minimum sensitivity of their device.

Such objections may or may not mean anything, but they need to be addressed, which is why real physics papers have disucssion of any possible sources of error that the experimentalists can think of.

I wish I knew what the flaw was :-(

You'll never know without the details.

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
Lots to discuss (none / 1) (#54)
by Alan Crowe on Mon Jun 27, 2005 at 12:34:16 PM EST

My physics is at the half forgotten undergraduate level. Nevertheless I can usually spot the flaw in a 2nd law breaker fairly quickly. Look at this suggestion from two years ago, and my rebuttal

Fu's device looks similar at first glance. Instead of a light-mumble-diode shining onto a light-mumble-diode to generate electricty, he has a thermionic emitter spraying electrons onto a thermionic reciever. So what? All he has done is to open a path so that the hotter can share its energy with the cooler.

Then he introduces the magnet. This matters because he is using charged particles instead of photons. Now if I want to run things backwards I have to reverse the polarity of the magnet. I cannot repeat my previous rebuttal. Naturally I want this to go to the front page. Then someone will post an explanation of why Fu's device will not actually work.

Is this kind of thing all that interesting? Yes! I read about the pawl and ratchet perpetual motion machine about 20 years ago. Later I was reading about DNA. You can think of the enzyme that copies DNA as a kind of machine that works its way along a single strand making the complimentary strand. But it is a very strange kind of machine, working at the atomic level. How does it know which way to go without some-one turning its handle?

Apparently it doesn't know which way to go. It chugs back and forth, making a bit of complimentary strand, and then unravelling it. If there is a strong concentration of Nucleic acids it the intra-cellular fluid average progress is forwards. If there is a weak concentration of nucleic acid, average progress is backwards.

When I read this I was very glad that I had already read about the pawl and ratchet machine. The notion that molecular level machines run both ways and need their direction set by a temperature gradient or a concentration gradient was already familiar, and I was able to understand the new stuff I was reading.

You'll notice the authors have no discussion of any potential systematic errors, there are no error bars, despite the fact that the measured currents are close to the minimum sensitivity of their device.

Fu's paper is half theory, half experiment. However he is not claiming any new physics. He is claiming a theoretical result, that he can use a magnet as a Maxwell's Demon. That is an extra-ordinary claim. It is natural to expect him to try it out.

There is much to worry about in his experiment set up. For example, with the magnets turned off, he zeros his electrometer. He simply assumes that no current is flowing. But if a current was flowing, then there would be a Hall effect when he turned on his magnet. Perhaps that is what he is seeing?

However, Fu is not claiming to have discovered new physics. He is proposing a novel arrangement of existing, well understood, elements. So the experimental part of his paper is a bit of a red-herring, the meat is in the theory. If the theory is sound researchers will soon get the experiment to work. If the theory is unsound Fu will discard his results as an artifact of a difficult to perform experiment; he is only trying to demonstrate the implications of his theory.

Ofcourse the theory is not sound. I would greatly apprecipate somebody telling me what is actually wrong with it. This is a theoretical issue and would still arise even if Fu had not reported any experimental results



[ Parent ]
The suggestion above (none / 0) (#56)
by manobes on Mon Jun 27, 2005 at 01:07:48 PM EST

about the electrons flying off the right edge of cathode B would be my guess as to where the flaw is. Likewise, those that *would* have flown off the left side of A are now curled back and land on A. It's clear from the diagram that the net charge on A wouldn't actually change. The "lost" electrons on the right are made up for by "curled in" electrons on the left.

I don't think your rebuttel is correct. The static electric field created by this would be massively weaker than the applied magnetic field (the mag field being approximatly constant across the apparatus, the static E field falling off as 1/r^2).

However he is not claiming any new physics.

He claims, at least twice, that this setup violates the second law of thermodynamics. That, if true, would certainly be "new physics".


No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
Thanks for the hint (none / 0) (#106)
by Alan Crowe on Wed Jun 29, 2005 at 07:11:40 AM EST

I think I've got it now.

Before the magnetic field is turned on, electrons are escaping from A and B in straight lines. They charge up the interior of the apparatus. An internal field builds up until equilibrium is reached, with the field strong enough to repel the thermionic electrons.

At this point electrons emitted from A and travelling to the right are bent down by the electric field (turning to their right) and land on B. Electrons emitted from B and travelling to the left are bent down by the electric field (turning to their left) and land on A. So far it is symmetric.

Now Fu turns on his magnet. Electrons emitted from A are pushed down by the electric field and turned to their right by the magnetic field. They turn right more than before, so the quantitative details are altered, but they still have a path to B.

Electrons emitted from B are pushed down by the electric field, which is trying to steer them round to their left. However the magnetic field is trying to steer them roung to their right away from A, so they are kinda stuck.

So we've got the central idea. Turn on the magnetic field and electrons trying to go left from B to A are out of luck.

OK so what really happens in crossed electric and magnetic fields? We have the electric field pushing electrons down the page, and the magnetic field going into the page. In these circumstances electrons follow a cycloidal path. If they are heading right the cusps point down the electric field. If they are heading left the cusps point up the electric field. And electrons can propagate as easily to the right as to the left. Whoops!

So electrons emitted from B and heading left aren't "kinda stuck". They need to turn left to reach A, but this is no problem. They go up the electric field, slowing down until they have nearly stopped, pull a tight 270 to the right, and then head back down the electric field to land on A.



[ Parent ]
What? (none / 0) (#107)
by Fon2d2 on Wed Jun 29, 2005 at 08:29:35 AM EST

Are you talking about some combination of electric and magnetic fields, because I don't see how it's possible with the magnetic field alone.

Let's consider figure 2. Let's call the dimensions represented by the paper x and y and the dimension into or out of the paper (the direction the magnetic field moves in) z. Movement of electrons in the z direction doesn't matter because it doesn't move them between A or B and it is not affected by the magnetic field.

Movement in the x,y direction however will always make a perfect circle. This circle will move upwards on the left and downwards on the right. Thus it would be impossible for any electrons from the B cathode to pass over and above the A cathode and simultaneously be moving down. They would keep moving up and around until they complete their circle somewhere back on the A cathode.

[ Parent ]

Yes combination of electric and magnetic fields (none / 0) (#109)
by Alan Crowe on Wed Jun 29, 2005 at 09:48:18 AM EST

The paper only talks about the magnetic field, but that is misleading. All those electrons leaving B and disappearing off to the right have to go somewhere. If you don't account for them you don't have a theory. That is a huge gap in the paper.

I've filled that gap in the obvious way by assuming that they charge up the inner surfaces of the device, which must then operate (or not) with an electric field present.

[ Parent ]

Yeah, I was wondering about that... (none / 0) (#110)
by Fon2d2 on Wed Jun 29, 2005 at 11:26:26 AM EST

My understanding of basic electro-magnetic theory is weak in this aspect. I think that's the route a lot of others took too in debunking the paper: eventually the charges would build up in such a way as to counteract the effect of the device.

The reason I find this aspect of electro-magnetics difficult is the question of what's happening to the electrons. Is the whole electrical system, including the cathodes, coming up with a net electron deficit and the inside walls of the container an electron surplus? This seems weird to me as it appears to violate Kirchoff's Current Law: the number of electrons that enter a node are the same as the number that exit. This even works across a capacitor but clearly one plate is gaining an electron surplus at the other plate's expense. So how can these extra electrons attach themselves? They just get immersed in the electron cloud? Is that how static electricty works?

I think these concepts are very poorly understood, even for EEs and that's why I haven't seen what I would call a satisfactory debunking of the article yet, although I still don't consider it valid.

[ Parent ]

Kirchoff's Current Law (none / 0) (#112)
by Alan Crowe on Wed Jun 29, 2005 at 01:09:39 PM EST

What is happening here is like what goes on inside a capacitor.



[ Parent ]
The problem, stated more explicitly. (none / 0) (#115)
by Fon2d2 on Wed Jun 29, 2005 at 02:58:19 PM EST

Presumably the plates of a capacitor are made out of the same material as the conducting wires that carry current through a system, or could be if they are not. Any one of these wires, or network thereof is a node as considered by Kirchoff's Current Law. This law states that the amount of charge that enters such a node is the same as the charge that leaves it. Hence, no buildup or deficit of electrons is possible in any one section of wire.

Now, considering the capacitor is made out of the same material as the wire (consider an open air parallel plate capacitor), where comes the distinction on we how we define the node at one end of the capacitor? If we drew our boundaries to include one full plate of the capacitor, instead of cutting off just before it, suddenly this would violate Kirchoff's Current Law.

This seems odd, since Kirchoff's Current Law seems to be saying something fundamental about the metal (there are always the same number of electrons within a certain amount of metal) yet the capacitor is clearly in violation of this observation.

The same is true for a cathode that has electrons escaping from it. Are these electrons being replaced somehow. Does a cathode ray violate Kirchoff's Current Law in some sense? Or is it just one device in a complete circuit and really a screen is collecting those electrons and feeding them back. If so, would the cathode ray still emit electrons without the screen? The answer appears to be yes, so what gives? The metal/entire-circuit gets a net positive charge?

[ Parent ]

Kirchoff's law is for lumped elements (none / 0) (#124)
by Alan Crowe on Fri Jul 01, 2005 at 07:29:50 AM EST

A pysical circuit exists in three dimensional space. When a current flows along a wire a magnetic field surrounds it, storing energy. When there is a potential difference between two parts of the circuit there is an electric field between, again storing energy.

For practical purposes this is hell.

Instead one makes a radical simplification. One considers ones circuits to be a network of ideal components, resistors, capacitors, inductors, voltage sources, and currect source, which is not embedded in three dimensional space and not made into an unanalisable whole by a fine tracery of electric and magnetic fields.

This is the lumped element approximation. That is where Kirchoff's law gets used.

It doesn't work for high frequency circuits because the electromagnetic fields are too important. Consequently high frequency circuits are very difficult to design.

An important intermediate between solving Maxwell's Equations for your phsical circuit and using Kirchoff's Laws on you circuit diagram is to stick with lumped elements but add in extra elements (usually capacitors) to try to fake the influence of the fields that you are leaving out. For example you might use a rule of thumb that adds 10pF to every package pin on a Dual-in-line package and mumble pico-Farads for every inch of printed circuit board track.

[ Parent ]

I think you still don't have it. (none / 0) (#117)
by glor on Wed Jun 29, 2005 at 04:13:12 PM EST

If a hunk of metal at thermal equilibrium in a heat bath can spit out electrons until some electric field returns them to the metal, then thermal energy has been converted into electrical energy (stored in the field).  It doesn't matter if the charges causing the field lie on a conductor or an insulator.  Extracting the energy from the field is an engineering problem.

If this thermal electron emission really happens when the metal and the heat bath are at the same temperature, I can think of several electrode configurations to get the energy out.  Not all of them involve insulators between the electrodes.  If you like I'll make a picture of one and show you.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

Good point (none / 0) (#119)
by Alan Crowe on Thu Jun 30, 2005 at 05:55:25 AM EST

I assemble a hollow device at absolute zero.

Half of the interior has a coating to make it a thermionic emitter.

I let it warm up to room temperature.

I think that I end up with an internal electric field sheparding electrons, that got flicked out by thermal agitation, back to where they belong.

I certainly have an energy source: I heated my device to make this happen.

Alternatively I could assemble the device at room temperature. When I bring the parts together, I squish the space charge around the thermionic emitter, and it is the work I do at this stage that is stored in the electric field.

Is that right?

[ Parent ]

Still not sure. (none / 0) (#121)
by glor on Thu Jun 30, 2005 at 02:21:31 PM EST

The question is, if you ground both sides of your device to discharge the field, does it build up again without any additional work?  I want to think the answer is "no," as it is for a diode connected to itself (current only flows one way, right?), but I can't make it work out yet in this case.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

Diodes are confusing (none / 1) (#123)
by Alan Crowe on Fri Jul 01, 2005 at 07:14:19 AM EST

The formula for the current through a semi-conductor diode is L * ( exp ( kV ) - 1 ), where L is the leakage current and k a fancy constant. For a silicon dioide L is tiny, and k about 22. So to get a worthwhile current in a practical circuit you need V about 0.7 volts, so that you have the rather large exp( 0.7 * 22) to cancel out the tinyness of L.

For microvolt thermal noise, you could expand the diode formula in a Taylor series. The leading term gives you linear behaviour, which is totally boring. The squared term will do something, but it is so small. It is going to be small compared to the thermoelectric effects. One would need to understand the second order thermoelectric effects when one connects to semi-conductors. So I'm well out of my depth here.

There has to been a connection between thermionic emission, the work function, and thermocouples. That might be the key to understanding this stuff

[ Parent ]

Ok, perhaps we were unclear, (none / 0) (#61)
by ElMiguel on Mon Jun 27, 2005 at 04:34:40 PM EST

Same as Alan, I'm actually only interested in the theoretical side of the paper. Perhaps we should have made it clearer.

What I was looking for is some discussion on this: if you actually set this device up like he suggested, what *should* happen?

Today I've been busy and I haven't been able to look further into this matter, but yesterday I was wondering mainly about this: when does thermionic emission stop in normal conditions? Surely, the outgoing electron current must charge the conductor positively and the resulting electric field would progressively make it harder for electrons to escape. After some time, the outgoing current must be so low as to be undetectable, while the conductor charge asymptotically approaches some positive equilibrium value.

So, why are the cathodes in the article's setup emitting? Is it because they have been set to a charge which is different from the thermionic equilibrium one? Then, some energy is necessary to give them that different charge, and it is that energy that they are spending while they emit.

You see, this is the type of discussion I hoped to have.

[ Parent ]

Okay, fine. (none / 0) (#67)
by manobes on Mon Jun 27, 2005 at 05:12:49 PM EST

What I was looking for is some discussion on this: if you actually set this device up like he suggested, what *should* happen?

My guess, from peering at the figure, is that nothing will happen. Look at Cathode A, he shows electrons curling off of that, onto B, but it's fairly clear that there will also be electrons which shoot out of A on the left side, curl around and land back on A. If the magnetic field is constant, then the charge on A will not change. Likewise B will lose electrons at the same rate it's getting them off of A. Without a changing charge, there will be no current.

The tiny current claimed to be observed is likely a systematic error. But we'll never know for sure because the writeup is so poor there's no way of telling what might be the source.

when does thermionic emission stop in normal conditions?

That I don't know. Most materials have a lot of electrons in them, so it would be a long while. You could emit a million electrons a second, for example, and it would take you 3 billion years to emit 10^23 electrons (which I picked because 6*10^{23} is a mole). I'm not a specilist in these sorts of materials though, so that's just a guess at the emmision rate.

So, why are the cathodes in the article's setup emitting?

The photoelectric effect.

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
No, that's not the reason Nobes is pulling rank. (none / 0) (#82)
by Surial on Mon Jun 27, 2005 at 11:36:12 PM EST

Nobes is pulling rank on his analysis of the qualities of the paper. And he's right on this. A paper written like that is just not useful to thoroughly work through.

Some believer will take that paper and do it all over again, from scratch, using that paper as a blueprint, but writing a REAL one, with all the stuff that's missing, including a test setup whereby the electric charge detector is not measuring at the very limit of its precision, either by getting a better sensor, or making the experiment generate more measurable power. Could be the author if this paper at some other university, perhaps, with better support. Or just the same guy with some more experience and a whole load of pointers under his belt.

Someone will include proper error bars and a more thorough observation in general.

Hopefully someone can try his or her hand at writing out a halfway decent list of stuff they didn't check but that should probably be checked before truely declaring the world's power issues solved permanently and forever. a.k.a. an analysis of possible systematic errors.

Until that paper is here, there's is absolutely no point in posting stuff like this on K5, and a professional is certainly not obliged due to professional courtesy to review such a thing for errors.

The claim is that a law that's been confirmed by thousands upon thousands of observations is not always true. That's a big one. It needs a lot more going for it than the current stack of smoke-and-mirrors before the chance, statistically speaking, that the hypothesis of this paper is really true, exceeds, say, one tenth of a percent.

--
"is a signature" is a signature.

[ Parent ]

In other words, (1.00 / 2) (#32)
by trhurler on Sun Jun 26, 2005 at 11:49:59 PM EST

You can't figure out why it won't work. Why not just admit it? It doesn't matter how much physics you know. The best trained physicists in the world have been wrong over and over again. Maybe this is complete nonsense. If so, someone will figure out why, and it won't work. OTOH, if it does work, then what you know IS WRONG. You are confusing science with its results, and confusing its results with some sort of Platonic ideal or something like that, all because you don't want to admit you can't figure out why it shouldn't work.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
physics not good (none / 0) (#47)
by fhotg on Mon Jun 27, 2005 at 06:23:49 AM EST

for general brain functions.

You are dense man.
~~~
Gitarren für die Mädchen -- Champagner für die Jungs

[ Parent ]

Totally incorrect, sir! (2.40 / 5) (#29)
by forgotten on Sun Jun 26, 2005 at 10:58:46 PM EST

It doesn't violate the second law of thermodynamics. That is the flaw. If it did, then it would work.

Your fancy physics degrees haven't helped you at all!!

--

[ Parent ]

Er, no (2.30 / 10) (#31)
by trhurler on Sun Jun 26, 2005 at 11:47:52 PM EST

Science as religion is worthless. The 2nd law was created from observations - nothing more. If an observation contradicts it and this can be confirmed, then it is the law that is wrong rather than the observation. Period.

Now I'm not saying this one has been confirmed - honestly, I suspect it won't be. BUT, pretending that the 2nd law is Truth[tm] means you are no longer a scientist, and are now a preacher.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
So let me get this straight (3.00 / 3) (#50)
by manobes on Mon Jun 27, 2005 at 08:24:19 AM EST

I'm supposed to debunk the details of every crackpot paper that I see? I'm not allowed to just call crap when I see it? That seems unfair.

BUT, pretending that the 2nd law is Truth[tm] means you are no longer a scientist, and are now a preacher.

Sure, fine. But the second law has been confirmed in thousands, of experiments. And along comes a two year old, unpublished, poorly written paper, claiming (in bold text no less) to have violated the second law of thermodynamics with a magnet, some wire, and a cathode. You'll have to pardon me for calling crap when I see it.

The truth of the matter is that I don't know what produced the tiny currents they claim to have seen. What I *do* know, is that their "paper" makes it totally impossible to tell if the effect is real. Some of the currents they claim to see are near the limits of their detector (10^{-14} amp), that obviously is a problem. Furthermore, having actually read proper experimental physics papers I know it's crap right off the bat because it lacks something that every good experimental physics paper should have a discussion of sources of systematic error. Without this, this writeup is useless, the effect could be anything.

Happy now?


No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
you are allowed to call crap (none / 0) (#55)
by speek on Mon Jun 27, 2005 at 12:47:47 PM EST

But when you do it without backing it up, it's as meaningless as the crackpot paper. So, now you've backed it up a little. Kudos.

--
al queda is kicking themsleves for not knowing about the levees
[ Parent ]

you could have read it by now (none / 0) (#58)
by Arkaein on Mon Jun 27, 2005 at 03:21:40 PM EST

and come up with a decent rebuttal for all the time you've spent dismissing the paper without argument.

So let me get this straight, I'm supposed to debunk the details of every crackpot paper that I see? I'm not allowed to just call crap when I see it?

If you're willing to comment on said paper or it's subject as much as you already have, yes you are supposed to debunk it. If it's not worth your time, then what are doing discussing it on K5? Either find the flaws or just quit talking about it.

----
The ultimate plays for Madden 2005
[ Parent ]

Perhaps you missed the point. (none / 0) (#59)
by manobes on Mon Jun 27, 2005 at 03:41:47 PM EST

You could have read it by now and come up with a decent rebuttal for all the time you've spent dismissing the paper without argument.

I did read it. It's not detailed enough to rebut, that's the problem. The theory seems flawed, but there's no detailed calculation. And there's no discussion of the systematics of the experiment. As I said in the post you responded to (which you read, no?), the effect is very small, at the limit of their detector. They don't seem to discuss this. There numbers have no error bars, a major warning flag. And so on, and so on. How much more "rebuttal" would you like?

No one can defend creationism against the overwhelming scientific evidence of creationism. -- Big Sexxy Joe


[ Parent ]
I agree (1.50 / 1) (#80)
by trhurler on Mon Jun 27, 2005 at 08:47:19 PM EST

The paper is certainly flawed. That said, had you said that up front and explained why, which apparently took you about five minutes, this would be completely different from what you actually did. As for having to debunk every crackpot paper that comes along, no, you don't have to - but you can't expect people to care what you have to say if you aren't going to say something interesting, either. "This observation is wrong because of the past history of observations" is neither logically correct nor interesting.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
You can't please everyone... especially here. (none / 0) (#127)
by birdsong on Sat Jul 02, 2005 at 11:23:05 PM EST

As you say, this has crank written all over it. I think every physics lab I've done, from high school through my four semesters of physics for engineering has included a discussion of possible sources of error. To not do so in a supposed groundbreaking paper is disingenuous at best.

[ Parent ]
Science as religion is worthless (none / 0) (#72)
by the on Mon Jun 27, 2005 at 06:56:30 PM EST

That's simply not true. I use the laws of geometric optics quite religiously every day in my attempts to render simulations of the real world. If I write some code that produces an unrealistic image I don't question The Laws of Geometric Optics. Not under any circumstances whatsoever. I question my code or the approximations I made to The Laws of Geometric Optics. I get paid for this. So how can you claim it's worthless?

--
The Definite Article
[ Parent ]
Wrong (none / 0) (#79)
by trhurler on Mon Jun 27, 2005 at 08:44:36 PM EST

You are not using it "religiously." You understand it, and you believe it to be true on the basis of the observations behind it and the lack of observations that contradict it. If you were to say "your observation of some aspect of the universe is wrong because of the laws of geometric optics," THAT would be religion, and it would be wrong. In order to show that an observation is mistaken, you must observe - quoting the past history of observations can NEVER substitute for this. Violate this rule, and you are a preacher.

--
'God dammit, your posts make me hard.' --LilDebbie

[ Parent ]
Now you're confusing me (none / 0) (#81)
by the on Mon Jun 27, 2005 at 09:23:21 PM EST

you believe it to be true on the basis of the observations behind it and the lack of observations that contradict it
I predict that such and such an algorithm will render a nice image because of my belief in the Laws of Geometric Optics. Someone else predicts this device won't work because of The Second Law (and so do I). You call one religion and one not. I don't understand the distinction. I think you'll have to spell it out for me. I'm sure Manobes understands the 2nd Law of Thermodynamics as well as I understand the Laws of Geometric Optics.

--
The Definite Article
[ Parent ]
I think I can clear this up for you (none / 0) (#83)
by procrasti on Tue Jun 28, 2005 at 05:17:50 AM EST

The point is you are not making observations, but a simulation.  You would have to observe something in the real world that contradicted the laws before your situation was analogous to this one.

Unfortunately, as manobes pointed out earlier, this paper is not really good enough to prove that they have observed what they say they have. Then again, the paper does look good enough for someone else to try and replicate the experiment with more rigour.

-------
if i ever see the nickname procrasti again on this site or anywhere in my life, i want it to be in an OBITUARY -- CTS
doing my best at licking arseholes - may 2015 -- mirko
-------
Winner of Kuro5hin: April 2015
[ Parent ]

Observations (none / 0) (#86)
by the on Tue Jun 28, 2005 at 09:08:06 AM EST

The point is you are not making observations
I was waiting for this objection but it's not valid. I am making observations. I'm comparing the results of my computation with reality all the time. And I'm even occasionally entering into new territory - eg. rendering stuff that hasn't been rendered before using methods that haven't been used before, all derived from Geometric Optics. At no point will I do anything other than slavishly use Geometric Optics. I will never question Geometric Optics while doing this. (Though I am aware that Geometric Optics has boundaries that I won't transgress eg. I won't render objects smaller than a wavelength.) I'm never going to discover new principles of optics outside of Geometric Optics, but my slavish use of the principles that I'm using isn't 'worthless'.

--
The Definite Article
[ Parent ]
Still Wrong (none / 0) (#91)
by procrasti on Tue Jun 28, 2005 at 12:13:02 PM EST

You are not making observations about reality, you are making observations about your simulation.  If you correctly code your simulation according to the laws you use, and then discover that reality is different, then you could say the laws were wrong.

So, if you use your simulation to do sub-wavelength rendering, and you could show this was different to what happens in reality, then you have shown that the laws don't apply at these wavelengths.

In other words, no amount of getting your simulation wrong can say anything about the laws or reality.  You have to show that you simulate the laws correctly and that this differs to reality to show that the laws were wrong.  This is what this paper is claiming, that the laws don't match reality.

-------
if i ever see the nickname procrasti again on this site or anywhere in my life, i want it to be in an OBITUARY -- CTS
doing my best at licking arseholes - may 2015 -- mirko
-------
Winner of Kuro5hin: April 2015
[ Parent ]

No (none / 0) (#97)
by the on Tue Jun 28, 2005 at 01:41:15 PM EST

You are not making observations about reality
Of course I am. I render a scene and then I look at the photograph of the scene I'm trying to render. They don't match. There must be something wrong with my code. I use observations from reality all the time: eg. photographs. I make comparisons between my simulations and reality continually. I also make predictions about reality (though more often 'retrodictions'). How would it look if I moved this light here? If the real result is different to my simulation I need to go back and fix my code, or my approximations. You're getting sidetracked by the rendering aspect here, it could be any other application of physics, but this just happens to be the one I currently use to make money.

you have shown that the laws don't apply at these wavelengths
One of the laws of Geometric Optics is that you can't use them to render objects smaller than a wavelength. It's built into the Laws of Geometric Optics already (at least the version I use). So no observation at subwavelength dimensions can ever show a contradiction with Geometric Optics just as no observation about the taste of cheese can never show a contradiction with Geometric Optics either.

--
The Definite Article
[ Parent ]
Simulation as prediction... (none / 0) (#104)
by Gooba42 on Tue Jun 28, 2005 at 09:49:37 PM EST

You can prove the laws invalid if you can code them properly and come up with unrealistic results.

Until the laws are proven wrong then you can prove your code wrong if you can prove it to be inconsistent with the laws.

In both of these cases the tip-off is the unrealistic results. The reason this test is flawed is because the failure of either the law or the code results in the same symptoms.

In your case you start your diagnosis with the code and if the code is fine then you look at the law but your experience has obviously been that the flaw is always in the code. This doesn't prove the law, it just proves your code isn't doing what you intended/expected it to do.

[ Parent ]

the difference i think i see (none / 0) (#111)
by goosedaemon on Wed Jun 29, 2005 at 11:57:11 AM EST

i think the religion comes into it when we deny that something could be so even if we observed it (regardless of whether we observe it or not), and we deny such only because it would violate the believed law. if we are closed-minded, if you will.

i am aware, of course, that the laws themselves have strong evidentiary support, and that there is a bit more than mere belief involved, but i'm afraid i can't think of a more appropriate word.



[ Parent ]
0, started (none / 1) (#95)
by Harvey Anderson on Tue Jun 28, 2005 at 01:16:30 PM EST

comment with 'er', 'uhm', 'uh'.

[ Parent ]
that's the flaw (none / 0) (#73)
by the on Mon Jun 27, 2005 at 07:39:13 PM EST

Really, that's not interesting. If you're so confident maybe you should actually read the paper and pin down the exact point where the second law is violated. This should be a trivial task. The paper is essentially a list of propositions about a piece of machinery. Presumably at the beginning it starts by making correct statements. Presumably, at the end, it makes claims incompatible with the second law. So a trivial bit of logic dictates that there must be a first sentence in the paper that is inconsistent with the 2nd law. Surely a physicist of your caliber can (1) find this proposition and (2) show how it doesn't follow from any other propositions in the paper.

--
The Definite Article
[ Parent ]
-1 If this got out our economy would be ruined. (1.14 / 7) (#7)
by tweetsybefore on Sun Jun 26, 2005 at 05:28:40 PM EST

Better to hide this technology from people so that there will never exist free energy.

I'm racist and I hate niggers.
Wonderful puzzle! (2.66 / 3) (#15)
by Alan Crowe on Sun Jun 26, 2005 at 06:07:00 PM EST

It is always fun to try and work out why a Maxwell's Demon doesn't actually work.

This one has me beat for now. It makes me realise that I don't understand thermionic emission. For example, why does he need a magnet? Wouldn't it be enough to use metals with different work functions, so that the thermionic current is greater one way than the other?



different work functions = thermo-couple (none / 0) (#46)
by Alan Crowe on Mon Jun 27, 2005 at 05:47:32 AM EST

I think I understand why using cathodes with different work functions is boring. It just re-invents the thermo-couple. Yes it will produce an EMF, but when you connect the two dis-similiar metals to your volt meter you get a voltage the other way. If the temperatures are the same the voltages will be the same and cancel out. So you need a temperature difference to get pwoer out = heat engine as usual.

[ Parent ]
Someone please explain (3.00 / 3) (#17)
by BottleRocket on Sun Jun 26, 2005 at 06:16:00 PM EST

Two similar and parallel Ag-O-Cs cathodes in a vacuum tube eject electrons at room temperature continuously.

How is that possible? Wouldn't that mean the cathodes increase in positive charge as they radiate electrons? It couldn't draw particles from the vacuum, and even if it could, why would it then radiate them back out?

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Yes I do download [child pornography], but I don't keep it any longer than I need to, so it can yield insight as to how to find more. --MDC
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$B R Σ III$

Eh (1.66 / 3) (#19)
by unknownlamer on Sun Jun 26, 2005 at 06:26:00 PM EST

+1SP just because I want to see a flamefest :-)

But yeah, it's bullshit.



--
<vladl> I am reading the making of the atomic bong - modern science
The Science Cabal Will Vote This Down (2.20 / 5) (#23)
by CheeseburgerBrown on Sun Jun 26, 2005 at 06:56:17 PM EST

The truth will get your telephone tapped.


_____
I am from a small, unknown country in the north called Ca-na-da. We are a simple, grease-loving people who enjoy le weeke
So (none / 1) (#70)
by trane on Mon Jun 27, 2005 at 06:28:15 PM EST

to protect your precious wife and family, you should avoid the truth, right?

In cb's philosophy of life, sex > truth.

[ Parent ]

Quick guess (none / 1) (#27)
by whazat on Sun Jun 26, 2005 at 08:29:07 PM EST

I expect he will lose electrons to the environment from the right edge of B in his diagram. So he might be increasing the entropy of the electrons.

So they pile up on the insulator (none / 0) (#45)
by Alan Crowe on Mon Jun 27, 2005 at 05:39:48 AM EST

This creates a static electric field. In equilibrium this is sufficient to guide nearly all the electrons back to B. Meanwhile the small deficit is cancelled by weaker thermionic emissions from the insulator. Weaker due to the higher work function of the insulator and the magnetic field, but aided by the electric field that has built up.

I've not done any calculations but this doesn't look to be the flaw in the Demon.

[ Parent ]

a magnet is not a free energy source (none / 1) (#40)
by Lode Runner on Mon Jun 27, 2005 at 01:54:43 AM EST



demons decrease entropy (3.00 / 2) (#41)
by dimaq on Mon Jun 27, 2005 at 03:13:19 AM EST

energy "gain" is just a side effect.

how is it different from other proposed demons? (none / 1) (#42)
by dimaq on Mon Jun 27, 2005 at 03:56:25 AM EST

e.g. diode demon? thermocouple demon?

IMHO the proposed device is in fact a diode of a kind anyway. there was a proposed open junction diode demon somewhere too.

Time reversal symmetry (none / 0) (#44)
by Alan Crowe on Mon Jun 27, 2005 at 05:33:51 AM EST

In mechanics and electro-statics the laws of physics are trivially time reversable. Feynam has fun showing that a ratchet-and-pawl perpetual motion machine is actually a heat engine and will run the "other way" if the temperature gradient is high enough.

When you come to make this kind of argument about Xin Yong Fu's Maxwell demon you hit a snag. To get the electrons to retrace their steps you have to make the electrons in the windings of the electro-magnet retrace their steps as well. This reverses the polarity of the magnet and makes the pathes of the elctrons curve the right way.

OK we've got the laws of physics being time symmetric, but unlike ratchet and pawl, in which the pawl jiggles about in Brownian motion, the retracing of steps includes the magnet, which is macroscopic. Its field is not fluctuating this way then that. So it is less obvious how to apply the usual arguments. I cannot see how to do so.

This is an interesting Maxwell's Demon, and going through the details of why it will not work will certainly improve my understanding of physics.

Has anyone cracked it yet?

[ Parent ]

same again (none / 0) (#84)
by dimaq on Tue Jun 28, 2005 at 06:19:03 AM EST

how is it different from diode demon? I wasn't asking about hairbrushes.

[ Parent ]
-1 troll (1.50 / 2) (#52)
by blue tiger on Mon Jun 27, 2005 at 11:09:47 AM EST

<cite>If you do try to find the flaw: don't say that the energy is extracted from the tearing of the magnet. This is not a good argument.</cite>
<p>
And why exactly this is not a good argument?
<p>
As far as I remember there is this third law of mechanics that say every action has an equal and opposite reaction, so I would expect that something happens to your 'permanent' magnet over time.
<p>
Moreover, to attempt contradict a law that has been verified time and time again for 150 years you have to come up with better experimental procedures. For starters, you might wanna measure fluctuations in the magnetic field intensity of your 'permanent' magnet. Later, you might want to make sure thare are no interferences. I haven't seen any Faraday cage mentioned. You might also want to double check your measuring equipment, i.e. also use a meter from a different company, preffereably with a different design.

Stop bashing the article/author (1.50 / 2) (#63)
by nlindstrom on Mon Jun 27, 2005 at 04:44:53 PM EST

An aweful lot of you seem to be confusing the article and the author with Xin Yong Fu. If you have a beef with the physics or Xin Yong Fu's truthfulness (or lack thereof,) great! But slamming the article or the author has nothing whatsoever to do with the issue of Xin Yong Fu's invention. And if you're going to claim that you're $DEITY's own gift to us uneducated masses, then either shut up and say nothing at all, or explain in a constructive fashion what is wrong with Xin Yong Fu's supposition. Anything else is just trolling, and goes to prove that you actually know nothing about physics.

my take on this (none / 0) (#74)
by khallow on Mon Jun 27, 2005 at 07:58:35 PM EST

The magnetic field is contributing energy to the system. After all, electrons are being forced by the magnetic field to climb up a voltage potential.

Stating the obvious since 1969.

They laughed at Columbus, they laughed at Fulton, (none / 1) (#75)
by bunsen on Mon Jun 27, 2005 at 07:59:44 PM EST

they laughed at the Wright brothers. But they also laughed at Bozo the Clown.

The flaw here boils down to pretty much the same reason you can't make a thermocouple increase free energy. When the system is set up, it's in a non-equilibrium state. Electrons being thermally emitted from the cathodes tend to move to the right (in figure 2(b) from the paper). This results in some charge being transferred from cathode A to cathode B, but charge will also be transferred from B to the right-hand end of the insulator and the wall of the tube. After a while (significantly longer than the experiment was run, apparently) enough charge will build up on the insulating surfaces that the electrostatic repulsion cancels the tendency to move electrons to the right. The system comes to equilibrium and the current between the cathodes ceases.

The author already figured out why this doesn't work, and explained it in a comment attached to the first version of the story. It seems a few other people have noticed the same flaw, but nobody seems to be listening to them.

Entirely apart from physical considerations, the paper in question is a piece of shit. Our own manobes has expounded at length on this, but the lack of detail in describing the experimental procedure and complete absence of any discussion of error make me wonder how this paper ever saw the light of day. I almost suspect that some professor got sick of these students pestering him with half-baked ideas like this and decided to expose them to the wrath of journal reviewers.

For those who enjoy searching for the flaw in devices which claim to violate the laws of physics, I recommend spending some time with the Museum of Unworkable Devices. It's mostly things that claim to violate the first law of thermodynamics, so they tend not to be subtle. If anybody knows of a similar compendium of second-law-violating inventions, I'd like to see it.

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On review: (none / 0) (#77)
by glor on Mon Jun 27, 2005 at 08:23:05 PM EST

You say
... the lack of detail in describing the experimental procedure and complete absence of any discussion of error make me wonder how this paper ever saw the light of day. I almost suspect that some professor got sick of these students pestering him with half-baked ideas like this and decided to expose them to the wrath of journal reviewers.
However, this is from arxiv.org, which is not peer-reviewed.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

Right. (none / 0) (#113)
by bunsen on Wed Jun 29, 2005 at 01:36:21 PM EST

This would never make it past reviewing. But arxiv.org is usually used for preprints of papers that get submitted to reviewed journals (at least that's what I read there; I've never spent much time browsing around). It's entirely possible that the authors have already been properly beaten by a real journal.

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[ Parent ]
It's not uncommon to 'publish' arxiv-only papers. (none / 0) (#116)
by glor on Wed Jun 29, 2005 at 03:04:38 PM EST

But it's not too common, either.

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Disclaimer: I am not the most intelligent kuron.
[ Parent ]

Some problems with the theory (none / 0) (#76)
by jd on Mon Jun 27, 2005 at 08:00:49 PM EST

First, you must consider the fact that you have two cathodes - ie: two negatively charged systems. Like charges repell. A single electron has a lower charge than the cathode it is going towards, so will always be deflected away from it.

(This is the principle that underlies all methods of steering electron beams, such as those in a cathode ray tube.)

Secondly, since both cathodes will be emitting, the two flows of electrons will repell each other and (in all probability) you will end up with placing a negative charge on the surrounding materials.

Thirdly, even if you DID get enough electrons to the second cathode, it would cease to be a cathode and become an anode, as current would be flowing in, not out, of the physical circuit at that point.

Fourth, perpetual motion is perfectly permissable, provided you don't take energy out. Many chemical reactions are dynamic equilibria and will eventually move in a full circle. It is the extraction of energy that is the problem, and the same is true here. If you extract energy, in this case, you break the circuit, as the circuit exists because of the flow of energy.

Energy Always Extracted (none / 0) (#88)
by hardburn on Tue Jun 28, 2005 at 11:31:57 AM EST

Fourth, perpetual motion is perfectly permissable, provided you don't take energy out. Many chemical reactions are dynamic equilibria and will eventually move in a full circle. It is the extraction of energy that is the problem, and the same is true here. If you extract energy, in this case, you break the circuit, as the circuit exists because of the flow of energy.

Doesn't the second law specify that a little bit of energy will always be extracted (usually in the form of heat)?


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[ Parent ]
Entropy must always increase... (none / 0) (#100)
by jd on Tue Jun 28, 2005 at 04:38:06 PM EST

...but only on a global level. On a local level, entropy can remain constant or even go down. Localized phenomina are not considered violations of the second law of thermodynamics, unless the system they are a part of is also in violation (which never happens).

This is because the law is statistical in nature, which means that what you have is a mean value which must be greater than zero, but you must also have a variance which is also going to be greater than zero. Any element, therefore, can potentially have a value of zero or even a negative value.

In the case of the chemical reaction, the net energy loss is zero, which means that there is an energy gain exactly (on average) equal to the energy loss, which means that localized region experiences zero net entropy. This would be impossible if the chemical reaction were the whole of the system, but entirely possible if it is only a component, provided another component is experiencing entropy great enough to keep the chemical reaction in a stable state.

[ Parent ]

Mass, not charge (none / 0) (#92)
by smithmc on Tue Jun 28, 2005 at 12:15:46 PM EST


A single electron has a lower charge than the cathode it is going towards, so will always be deflected away from it. (This is the principle that underlies all methods of steering electron beams, such as those in a cathode ray tube.)

The relative quantities of charge are not what dictates that the electron will move away from the cathode. Like charges repel, regardless of quantity. The reason the electron moves away from the cathode, rather than vice versa, is simply that the electron is much less massive than the cathode (and the chassis to which the cathode is likely attached), therefore the acceleration of the electron is much larger than the acceleration of the cathode.

[ Parent ]

Weaker than Other Laws? (none / 1) (#87)
by hardburn on Tue Jun 28, 2005 at 11:28:19 AM EST

Isn't the second law considered not as absolute as other physical laws? IIRC, it's something that happens almost every time, but there is a small, but non-zero, chance that entropy won't increase.

For instance, consider throwing a deck of cards in the air and picking them up. There is a small chance that you will pick them up in order Ace - King, Hearts, Diamonds, Spades, and Clubs. If you did that, entropy would not increase (glossing over the increase created by your body's release of heat while picking the cards up). But entropy would increase in all the cases where the ending deck was random.


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Disorder isn't entropy (none / 0) (#94)
by pdrap on Tue Jun 28, 2005 at 12:41:10 PM EST

I hate the card example because it's NOT entropy. All possible orderings of the cards have exactly the same entropy, because the energy of the system is the same, regardless of the order of the cards.


[ Parent ]
Not Scientifically Rigrous (none / 0) (#99)
by hardburn on Tue Jun 28, 2005 at 02:44:50 PM EST

Sure, it's not the most scientifically rigrous example, but I think it shows the point well enough.

The first day of class, my High School Physics teacher said "In this class, our job is to lie to you. We'll try to lie to you less than your other classes, but lie we must." His point was that, for the purposes of learning, it's sometimes necessary to gloss over details that would invalidate your point in some cases. It's better to learn the basics first, then get into the more complex points that may show some flaws in the initial reasoning.


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[ Parent ]
Not quite true (none / 0) (#120)
by dcturner on Thu Jun 30, 2005 at 01:20:48 PM EST

If you had 52 blank cards then yes, every ordering would have the same entropy. But because each card may be distinguished, there are a few orderings which have much much lower entropy than most of the others.

In information theory, the entropy of a system is roughly the number of bits you need to describe it to a distant friend, and you can say 'in order' much quicker than '2 clubs, 4 spades, 3 spades, 10 hearts, ...'.

The trouble is that information-theoretic entropy (which is what the cards are about) and physical entropy are worlds apart in the number of bits/amount of entropy they're talking about. But they're the same concept just at different scales: think of entropy as the number of ways you can rearrange a system without anyone being able to tell the difference.

Remove the opinion on spam to reply.


[ Parent ]
yepp (none / 0) (#96)
by fhotg on Tue Jun 28, 2005 at 01:34:54 PM EST

small fluktuations towards smaller entropy are explicitely allowed.
~~~
Gitarren für die Mädchen -- Champagner für die Jungs

[ Parent ]
In fact it is stronger! (none / 1) (#128)
by kkumer on Mon Jul 04, 2005 at 05:57:49 AM EST

You are right that there is some small probability of fluctuations that could localy, for a short time, spontaneously decrease entropy. However, you cannot base a perpetuum mobile of the second kind (and this is what these guys propose) on such fluctuations. You will have machine that would operate as advertised only one nanosecond in several universe lifetimes.

Anyway, laws of thermodynamics are usually considered more safe than most, if not all, of conventional science theories. Let me quote Eddington:

The law that entropy always increases -- the second law of thermodynamics -- holds I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations - then so much worse for Maxwell equations. If it is found to be contradicted by observation - well these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of Thermodynamics, I can give you no hope; there is nothing for it but to collapse in deepest humiliation.


[ Parent ]
I have to venture a guess... (none / 0) (#93)
by Fon2d2 on Tue Jun 28, 2005 at 12:20:37 PM EST

I'd have to go with others and say it won't work because eventually electrons will pile up around Cathode B and provide a strong enough repelling force. Or it'll run out of electrons. This is essentially saying that the equilibrium state of the system without the load and magnetic field is not the same as with them. Thus it's only a matter of time before the system equalizes itself again. It is also saying the energy is inherint in the system to begin with, like a ball starting at the top of a hill.

The energy is not, as some assert, coming from the magnets. I explain why that is here.

The author of the paper seems to assert the energy is coming from the ambient air temperature. Hence the cathode and tube are actually getting colder and sucking heat from the surrounding environment. This, to me, is a big assertion and unfortunately I saw no measurements of temperature along with their other measurements. If this is true, it means they really have created a Maxell's Demon. It also means the device can provide refrigeration at the same time it provides free energy. This is a pretty big statement. Or else the drop in temperature is just a side effect caused by something like the Peltier effect and powered by the potential energy inherint in the system's starting state.

extraordinary claim, extraordinary evidence (none / 0) (#98)
by boxed on Tue Jun 28, 2005 at 02:26:44 PM EST

That's how science works, and I'm not seeing something even close to extraordinary evidence, in fact, I'm seeing pretty much nothing except a reason to do more research (at best). This is news when it's confirmed, before then it's astrology.

doesn't work (none / 0) (#101)
by jcarnelian on Tue Jun 28, 2005 at 05:11:35 PM EST

It doesn't work.  Here is a simple qualitative argument that uses basically the same conceptualization as the authors.

In the diagram, the two electrodes sit on insulators, so that it looks like electrons are only ejected at the top; if the insulators weren't there, then the flow of electrons would be symmetric: from the top of the left electrode to the top of the right one, and from the bottom of the right electrode to the bottom of the left one.  For their argument to work, the bottom flow has to be blocked so that the return flow can happen via a wire, and the insulator is therefore an essential part of the function of the device.

Now, to avoid complicating the discussion with interface effects, imagine that there is a little gap between the electrodes and the insulators they sit on.  What happens to the bottom flow?  The electrons coming off the bottom of the right electrode will build up on the insulator and create an electric field.  This electric field will counteract the current.

So, why do they see any current at all?  The device is basically just a circuit that has the two sides of a capacitor connected through an amp meter.  They are moving that circuit into a magnetic field, and that induces a current, just like it would in any wire loop.

Your counterarguments are flawed. (none / 0) (#103)
by glor on Tue Jun 28, 2005 at 07:43:14 PM EST

I assume you're referring to the schematic, Figure 2, and not the actual device shown in Figure 3. If the electrodes in the schematic were lifted above their insulator by a distance smaller than the electron cyclotron radius, you'd get the same buildup of charge on both sides.

In any case I think your argument doesn't apply to the actual device, which has a single mica sheet between the electrodes. Furthermore, suppose your objection were correct, that an electric field due to charge on the insulator is what stops the current (rather than a charge on the electrodes). This electric field contains stored energy, which has come from someplace.

As for the current being induced by the changing magnetic field, the authors say on p.6 that the current is produced by a static field:

Then, step by step, strengthen the magnetic induction B+ by reducing L, giving a sufficiently long pause for every step (to eliminate Farady's motional electric motive force), we get every time a stable current I+ corresponding to a stable magnetic induction B+.
I agree with you that this report is not likely to be correct, but I don't agree with your reasoning.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

counterarguments (none / 0) (#105)
by jcarnelian on Wed Jun 29, 2005 at 12:26:49 AM EST

In any case I think your argument doesn't apply to the actual device, which has a single mica sheet between the electrodes.

Well, and charges will accumulate differentially on the two sides of the mica sheet.

If the electrodes in the schematic were lifted above their insulator by a distance smaller than the electron cyclotron radius, you'd get the same buildup of charge on both sides

No, because the momentum distribution of the thermionic radiation is affected by the presence of the magnetic field.

Furthermore, suppose your objection were correct, that an electric field due to charge on the insulator is what stops the current (rather than a charge on the electrodes). This electric field contains stored energy, which has come from someplace.

If you accept that charges do accumulate, then you accept that we are talking at most about a finite amount of energy, rather than something that can convert heat into electricity indefinitely, which means that the authors' argument doesn't work.

As for the current being induced by the changing magnetic field, the authors say on p.6 that the current is produced by a static field:

I didn't mean to imply that the magnetic field induced a current in a wire that then got stored in a capacitor.  Rather, I was trying to get across that the circuit is analogous to such a circuit, but because part of the circuit is a thermionic current flow, the time scales are longer.

I agree with you that this report is not likely to be correct, but I don't agree with your reasoning.

I'm not sure what you are after.  While there might be physical effects that let us circumvent the "laws" of thermodynamics, one can easily prove that these kinds of systems combining electromagnetism and heat cannot.  However, such a general argument isn't very illuminating.  Hence, it's nice to be able identify a simple, intuitive flaw with any particular proposal.

[ Parent ]

Still flawed. (none / 0) (#114)
by glor on Wed Jun 29, 2005 at 02:57:42 PM EST

I don't agree with you about the charge buildup on the insulator. I could convince you at a blackboard, but I'm not enough of a writer. However, you seem to think that a charge buildup occurs somewhere:
If you accept that charges do accumulate, then you accept that we are talking at most about a finite amount of energy, rather than something that can convert heat into electricity indefinitely, which means that the authors' argument doesn't work.
Sure, the capacitor has a maximum charge at a given temperature. However if it's discharged, it will apparently recharge itself from the heat in the air. The authors argue that the discharge/recharge process can be repeated indefinitely (or continuously, as they claim to have done).
I didn't mean to imply that the magnetic field induced a current in a wire that then got stored in a capacitor. Rather, I was trying to get across that the circuit is analogous to such a circuit, but because part of the circuit is a thermionic current flow, the time scales are longer.
I'm not sure what you mean by "analagous." Induced currents only happen when a magnetic field is changing. You're right that the authors don't make any statements about how long the current is stable. My unsubstantiated guess is that their magnets take tens of seconds to move, they wait tens of seconds of the transients to settle out, and the current appears stable over tens of seconds, maybe a couple minutes. If I'm close, the experiment is interesting. But I didn't see any such information in the article, apart from the claim that they waited for the transients to go away.
I agree with you that this report is not likely to be correct, but I don't agree with your reasoning.
I'm not sure what you are after. While there might be physical effects that let us circumvent the "laws" of thermodynamics, one can easily prove that these kinds of systems combining electromagnetism and heat cannot. However, such a general argument isn't very illuminating. Hence, it's nice to be able identify a simple, intuitive flaw with any particular proposal.
I agree with you. I just don't think you've correctly identified the flaws in this experiment. There are several things it could be. My current (again, unsubstantiated) guess is that it's an outright lie intented to attract the financial support of the Chinese military. That's what became of Taleyarkhan after he claimed to have produced fusion using sonoluminescence in 2002: the DoD took over his funding. But I haven't figured out what the problem really is yet.

--
Disclaimer: I am not the most intelligent kuron.
[ Parent ]

I'm not sure I understand what you want (none / 0) (#122)
by jcarnelian on Thu Jun 30, 2005 at 05:58:43 PM EST

I agree with you. I just don't think you've correctly identified the flaws in this experiment.

If you actually want to show that the system doesn't work, the way to do it isn't to try to find bugs in their argument, you just show it for the general case (and this kind of system can't work). All I was trying to point out is that the model the authors present isn't even internally consistent.

That leaves open the question of where the tiny current they observe actually comes from. I'm not a materials scientist, so I don't have a good intuition for it.  I think you could find out by using different materials for the electrodes and insulators, different temperatures, and different rates of change of the magnetic field.  For anything even remotely resembling their model, I believe there should be a predictable dependence on temperature and electrode materials, no dependence on the insulator, and no dependence on rate of change of the magnetic field.  The alternative explanations I could imagine would behave differently.

[ Parent ]

What I don't get... (none / 0) (#108)
by Fon2d2 on Wed Jun 29, 2005 at 08:39:57 AM EST

Why do both sides have to be cathodes? Wouldn't cathode B be losing as many electrons as it's receiving? If cathode A is losing n electrons if it's right-hand side to cathode B, wouldn't cathode B be losing just as many every second onto the insulator?

And look at the way their electron tube is actually built and placed in the magnetic field. Both tops and bottoms of the cathode are exposed, so why don't electrons flow back from B to A along the bottom? Unless the diagram is supposed to be showing that mica sheet extended below the insulators somewhat.

Why couldn't you just have one thermionic cathode pointed towards an anode and no magnet? What would be the difference here? Or would B not accept electrons unless it already emitted some or something?

Also they claimed the device causes a slight drop in temperature, yet they show no measurements of this in their result. One would think such a measurement would be too important to ignore.

really. (none / 0) (#129)
by fullmetalcolumnist on Wed Jul 06, 2005 at 11:22:31 AM EST

That kind of omission makes me want to build it this week... since an air conditioner that runs the blower from the heat it removed from the air would be nice. That air's motion will become heat before long, so of course the blower motor would have to be outside. No need for a compressor or condenser, just cycle water through a regular radiator and then through a heat exchanger embedded in the tube's insulator. If it got cold enough, it could at least serve as a dehumidifier...

I was thinking about how cool a hypersensitive peizoelectric crystal hooked through a diode could do the same thing, but got stuck on the impossibility of creating a crystal that would deliver volts from mere thermal vibrations. Actually stuck on a $0 budget and no formal education... Oh, yeah, sure am glad I bought those bone-crushing magnets with my student loan money. Watercooling a PC by recovering a hundred watts or so... Hmm, also makes me glad I quit smoking weed... (no, still off it.)

But what's all this about electrons building up in the tube? It's not a general increase, it's an imbalance. The moment you close the circuit, the "capacitor" discharges. The number of electrons in the entire tube assembly should never change, only be redistributed.

The idea that electrons build up on the insulator is probably right on. I see the 2 cathodes charging the capacitor formed by them, but the vacuum+magnets create conditions for the ambient heat to charge that capacitor. Yeah... and I know who has a vacuum pump.



---
Sanity is not statistical. --George Orwell
[ Parent ]
Maxwell's deamon (none / 1) (#118)
by gerMusic on Wed Jun 29, 2005 at 06:28:49 PM EST

1. This demon is does it's work with the help of outside (infrared) energy which is freeing electrons. Maxwell's proposed demon is making a separation between the atoms/molecules inside the same system. This device is a complex way of moving 'electron' heat in a particular way.
A kind of heat pump the electronic way
2. the 2e law states that systems tends to strive to a maximum entropy (disperse the energy in as many forms as possible). The first law states that energy can't disappear or being created from nowhere. Crucial are the words 'tends to' in the second law, nowhere is stated that the energy is
irreversible lost into heat and can not converted into more usefull form.
3. We do create electricity from heat, by burning fuels. The advantage here is that there isn't a waste product like CO2 or water. But the same could be achieved with a heat power driven Stirling engine.

No laws are broken, no 'free' energy is generated. And Maxwell's demon isn't build (yet)

VACUUM tube - how long? (3.00 / 2) (#125)
by MvG on Fri Jul 01, 2005 at 07:30:50 PM EST

Well, I'd expect the problem to be with the idea of a vacuum tube staying evacuated forever. As both electrodes emit electrons, sooner or later the space will be filled by electrons, so that at some time the electrons could no longer move freely from A to B. So although there are no different temperatures, there is in fact a huge difference in pressure - between the electrodes and the tube. This difference will decrease, increasing entropy and thus keeping the second law intact.

Another flaw. (none / 0) (#132)
by systemloc on Sun Aug 07, 2005 at 01:53:23 PM EST

The electrodes are refined metal, which takes energy to produce. As electrons break free from the metal, the remaining atoms are electron poor, thus ions, or oxidized. The metal will eventually be depleted back into oxidized metal as all of the electrons easily broken away are lost. As energy is harvested, entropy of the metal is increased.

Not in a no-oxygen environment. (none / 0) (#133)
by glor on Mon Aug 22, 2005 at 05:38:26 PM EST


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[ Parent ]

Maxwell's thermodynamic daemon realized ? | 133 comments (122 topical, 11 editorial, 0 hidden)
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