Exorcising Maxwell’s Demon
Physicists have been haunted by the idea of Maxwell's demon for almost 150 years. The beast, conjured in a thought experiment by James Clerk Maxwell, sorts particles in a gas according to their speeds, thus transferring heat from the colder, evenly mixed gas to the region containing the hotter, high-speed particles. At first sight, the demon appears to violate the second law of thermodynamics. But the paradox can be resolved by realizing that work must be performed on the demon for it to do its job properly. This description isn’t entirely satisfying, however, as it introduces an external—not necessarily physical—entity to do work on the demon.
Jukka Pekola and colleagues of Aalto University in Finland  have now exorcised such nonphysical beings by realizing a nanodevice equivalent to a Maxwell's demon (Fig. 1), but one whose operation doesn’t depend on an external entity. This so-called autonomous device, also known as an information machine, is completely self-contained. So far, autonomous demons have been a purely theoretical concept; this new experimental system provides a way to test formulations of fundamental axioms of thermodynamics and descriptions of information processing.
In the second half of the 19th century, the second law of thermodynamics was still relatively new. The law had been restated to describe specific situations, including, for instance, that heat cannot be transferred from cold to hot without doing work (Clausius statement), and that heat engines cannot operate with 100% efficiency (Carnot statement) . But physicists questioned whether the second law was true for a system whose properties were governed by the average behavior of many particles or if it held for each individual particle.
To illustrate the average quality, Maxwell proposed, in an 1867 letter to his colleague Peter Tait, a thought experiment that allowed a violation of the Clausius statement . Maxwell imagined two boxes, filled with a gas of particles and separated by a common wall. A “neat fingered being,” capable of measuring each particle’s velocity, sat by a little door in the wall. This being could sort particles by opening and closing the door, allowing only fast particles to go to the right and only slow particles to the left. This sorting process would, in direct violation of the Clausius statement, transfer heat from a cold reservoir to a hot one.
Maxwell's demon was an instant source of fascination and led to many important results, including the development of a thermodynamic theory of information. But a particularly important insight came in the 1960s from the IBM researcher Rolf Landauer . He realized that the extra work that can be extracted from the demon’s action has a cost that has to be “paid” outside the gas-plus-demon system.
Specifically, if the demon’s memory is finite, it will eventually overflow because of the accumulated information that has to be collected about each particle’s speed. At this point, the demon’s memory has to be erased for the demon to continue operating—an action that requires work. This work is exactly equal to the work that can be extracted by the demon’s sorting of hot and cold particles. Properly accounting for this work recovers the validity of the second law. In essence, Landauer’s principle means that “information is physical” . But it doesn’t remove all metaphysical entities nor does it provide a recipe for building a demon. For instance, it is fair to ask: Who or what erases the demon's memory? Do we need to consider an über-demon acting on the demon?
Szilard was never comfortable with the need to introduce a metaphysical, human-like intelligence to operate Maxwell’s demon. Instead, he thought that it should be possible to construct autonomous, maybe even mechanical, systems that act like a demon yet fully obey the laws of physics—a fully inclusive conceptual approach. Although the idea has attracted a lot of attention, it has only been realized in theoretical form. (For recent examples, see Refs. [9, 10].)
The work by Pekola and colleagues has made Szilard’s autonomous demon a physical reality. Their device consists of two single-electron boxes: a “system” box and a “demon” box. The system box is made of a small metal (copper) island connected to two metal leads via superconducting aluminum junctions that allow electrons to tunnel onto and off the island. (Using superconducting materials ensures that electrons are transported without transference of heat, allowing the authors to accurately track the heat entering and leaving the system and the information exchanged with the demon.)
The system box is coupled to a neighboring demon box with a similar electronic structure, which detects the voltage associated with an electron either entering the island or leaving it (Fig. 1). This voltage, in turn, activates the demon: When an electron tunnels onto the island, the demon box is designed to trap it by applying a positive charge; if an electron leaves the island, the demon repels it by applying a negative charge. The charge induced by the demon forces the electrons to tunnel against a potential—the electrons must move uphill—and the system cools down. No external control drives the action of the demon (it is thus autonomous), and the whole process is accomplished because of the clever way in which the two electron boxes are coupled.
The researchers showed that the demon’s actions make the system’s temperature drop and the demon’s temperature rise, in agreement with the predictions of a simple theoretical model. The temperature change is determined by the so-called mutual information between the system and demon. This quantity characterizes the degree of correlation between the system and demon; or, in simple terms, how much the demon “knows” about the system.
We now have an experimental system that fully agrees with our simple intuition—namely that information can be used to extract more work than seemingly permitted by the original formulations of the second law. This doesn’t mean that the second law is breakable, but rather that physicists need to find a way to carefully formulate it to describe specific situations. In the case of Maxwell’s demon, for example, some of the entropy production has to be identified with the information gained by the demon.
The Aalto University team’s experiment also opens a new avenue of research by explicitly showing that autonomous demons can exist and are not just theoretical exercises. For example, understanding the information contribution to entropy production might become important in cases where information needs to be written or read with high efficiency—such as the remote operation of a computer in humans or in space.
One day, we might have a truly mechanical demon, as envisioned by Szilard  and in more recent theoretical proposals . Like mechanical heat engines, mechanical demons are easier to visualize than their electrical counterparts and could therefore better illustrate fundamental principles of thermodynamics. Play the Maxwell's Demon Game online. - JWD
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Finally, I've gotten around to compiling all the files (almost 1,000 - about 20MB and lots of work doing it) from the original KeelyNet BBS into a form you can easily navigate and read using your browser, ideally Firefox but it does work with IE. Most of these files are extremely targeted, interesting and informative, I had forgotten just how much but now you can have the complete organized, categorized set, not just sprinklings from around the web. They will keep you reading for weeks if not longer and give you clues and insights into many subjects and new ideas for investigation and research. IN ADDITION, I am including as a bonus gift, the book (in PDF form) that started it all for me, 'Keely and his Discoveries - Aerial Navigation' which includes the analysis of Keely's discoveries by Dr. Daniel G. Brinton. This 407 page eBook alone is worth the price of the KeelyNet BBS CD but it will give you some degree of understanding about what all Keely accomplished which is just now being rediscovered, but of course, without recognizing Keely as the original discoverer. Chapters include; Vibratory Sympathetic and Polar Flows, Vibratory Physics, Latent Force in Interstitial Spaces and much more. To give some idea of how Keely's discoveries are being slowly rediscovered in modern times, check out this Keely History. These two excellent bodies of information will be sent to you on CD. If alternative science intrigues and fascinates you, this CD is what you've been looking for...
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Years ago, I had been told by several people, that the US government frequently removes books they deem dangerous or 'sensitive' from libraries. Some are replaced with sections removed or rewritten so as to 'contain' information that should not be available to the public despite the authors intent. A key example was during the Manhattan Project when the US was trying to finalize research into atomic bombs. They removed any books that dealt with the subject and two of them were by Dr. Gustave Le Bon since they dealt with both energy and matter including radioactivity. I had been looking for these two books for many years and fortunately stumbled across two copies for which I paid about $40.00 each. I couldn't put down the books once I started reading them. Such a wealth of original discoveries, many not known or remembered today. / Page 88 - Without the ether there could be neither gravity, nor light, nor electricity, nor heat, nor anything, in a word, of which we have knowledge. The universe would be silent and dead, or would reveal itself in a form which we cannot even foresee. If one could construct a glass chamber from which the ether were to be entirely eliminated, heat and light could not pass through it. It would be absolutely dark, and probably gravitation would no longer act on the bodies within it. They would then have lost their weight. / Page 96-97 - A material vortex may be formed by any fluid, liquid or gaseous, turning round an axis, and by the fact of its rotation it describes spirals. The study of these vortices has been the object of important researches by different scholars, notably by Bjerkness and Weyher. They have shown that by them can be produced all the attractions and repulsions recognized in electricity, the deviations of the magnetic needle by currents, etc. These vortices are produced by the rapid rotation of a central rod furnished with pallets, or, more simply, of a sphere. Round this sphere gaseous currents are established, dissymetrical with regard to its equatorial plane, and the result is the attraction or repulsion of bodies brought near to it, according to the position given to them. It is even possible, as Weyher has proved, to compel these bodies to turn round the sphere as do the satellites of a planet without touching it. / Page 149 - "The problem of sending a pencil of parallel Hertzian waves to a distance possesses more than a theoretical interest. It is allowable to say that its solution would change the course of our civilization by rendering war impossible. The first physicist who realizes this discovery will be able to avail himself of the presence of an enemy's ironclads gathered together in a harbour to blow them up in a few minutes, from a distance of several kilometres, simply by directing on them a sheaf of electric radiations. On reaching the metal wires with which these vessels are nowadays honeycombed, this will excite an atmosphere of sparks which will at once explode the shells and torpedoes stored in their holds. With the same reflector, giving a pencil of parallel radiations, it would not be much more difficult to cause the explosion of the stores of powder and shells contained in a fortress, or in the artillery sparks of an army corps, and finally the metal cartridges of the soldiers. Science, which at first rendered wars so deadly, would then at length have rendered them impossible, and the relations between nations would have to be established on new bases."
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High Voltage & Free Energy Devices Handbook
This wonderfully informative ebook provides many simple experiments you can do, including hydrogen generation and electrostatic repulsion as well as the keys to EV Gray's Fuelless Engine. One of the most comprehensive compilations of information yet detailing the effects of high voltage repulsion as a driving force. Ed Gray's engine produced in excess of 300HP and he claimed to be able to 'split the positive' energy of electricity to produce a self-running motor/generator for use as an engine. Schematics and tons of photos of the original machines and more! Excellent gift for your technical friends or for that budding scientist! If you are an experimenter or know someone who investigates such matters, this would make an excellent addition to your library or as an unforgettable gift. The downloadable HVFE eBook pdf file is almost 11MB in size and contains many experiments, photos, diagrams and technical details. Buy a copy and learn all about hydrogen generation, its uses and how to produce electrostatic repulsion. - 121 pages
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Hypnosis CD - 3 eBooks with How To Techniques and Many Cases
If you have a few minutes, you might want to read my page on hypnosis and all the amazing things associated with its application. Included is an experience I had when I hypnotized a neighbor kid when I was about 14. As well the hypnotic gaze of snakes, the discovery of 'eyebeams' which can be detected electronically, the Italian Hypnotist Robber who was caught on tape with his eyes glowing as cashiers handed over their money and remembered nothing, glamour and clouding the mind of others, several methods of trance induction and many odd cases, animal catatonia, healing, psychic phenomena, party/stage stunts, including my favorite of negative hallucination where you make your subject NOT see something...much more...if nothing else, its might be a hoot to read.
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This eBook is the result of years of research into various methods to increase mileage, reduce pollution and most importantly, reduce overall fuel costs. It starts out with the simplest methods and offers progressively more detailed technologies that have been shown to reduce fuel costs. As a bonus to readers, I have salted the pages with free interesting BONUS items that correlate to the relevant page. Just filling up with one tank of gas using this or other methods explained here will pay for this eBook. Of course, many more methods are out there but I provided only the ones which I think are practical and can be studied by the average person who is looking for a way to immediately reduce their fuel costs. I am currently using two of the easier methods in my own vehicle which normally gets 18-22 mpg and now gets between 28 and 32 mpg depending on driving conditions. A tank of gas for my 1996 Ford Ranger costs about $45.00 here so I am saving around $15-$20 PER TANK, without hurting my engine and with 'greener' emissions due to a cleaner burn! The techniques provided in this ebook begin with simple things you can do NOW to improve your mileage and lower your gas costs. - eBook Download / More Info
The Physics of the Primary State of Matter
The Physics of the Primary State of Matter - published in the 1930s, Karl Schappeller described his Prime Mover, a 10-inch steel sphere with quarter-inch copper tubing coils. These were filled with a material not named specifically, but which is said to have hardened under the influence of direct current and a magnetic field [electro-rheological fluid]. With such polarization, it might be guessed to act like a dielectric capacitor and as a diode...
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No time to sit back and watch videos? Here are 15 interesting presentations you can download for just $5 each and listen to while driving, working, jogging, etc. An easy way to learn some fascinating new things that you will find of use. Easy, cheap and simple, better than eBooks or Videos. Roughly 50MB per MP3.
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