But do they superconduct?

Fourth in a series; first is here.

[Epistemic status: speculative. This is more an exploration than an explanation. I am basically trying to get my thoughts together on the subject. Any comments would be quite valuable!]

So the question is, do condensed plasmoids actually condense in the sense of a superconductor? Also, why does it matter? The conductivity of a plasma is generally cited as about that of copper, anyway. The runaway pinch effect is well noted under the name of "sausage instability," and is also noted for causing floods of neutrons if there is deuterium in the plasma mixture. Note that the referenced paper (from 1960!) goes on to say, "Subsequent to the blowup of the instability, the plasma-field configuration is such that the accelerated deuterons can continue to circulate in stable orbits until lost by neutron-producing collisions or by diffusion out of the ends of the geometry."

In more recent times, there has been a lot of work on fusion in plasmas, and specifically using ζ-pinch effects in various geometries. There have been numerous, in-depth studies, e.g. here and here, simulating the electromagnetodynamics of them. That being the case, why haven't plasmoids been more generally predicted, recognized, and experimented with?

One obvious explanation is that no one is looking for them. Existing theories of superconductivity, such as BCS, do not predict that it can happen in plasmas. Plasmas are hot and superconductors are cold. The dynamics of a superconductor are that electrons, which are fermions (which must occupy different states), can pair off into coordinated states that allow a pair of them, called a Cooper pair, to act enough like bosons, which can occupy the same state and thus "condense" into a collective entity which has drastically different properties from the electrons acting individually. But in standard theory, Cooper pairs rely on an attractive force that arises from phonons in the solid crystal structure of the superconductor. (Popular explanations of this are at best misleading, showing electrons as localized points which cause an attractive bunching in the lattice, which then attracts the other electron. But in actuality the electrons are delocalized and are required to have equal and opposite momenta, acting in concert (see above).)

The ζ-pinch itself is nothing more than an attractive magnetic force between (moving) electrons. Although it is beyond my level to sit down and write up a Schrödinger (or Dirac?) equation and Hamiltonian that would be the equivalent to a Cooper pair, it seems like something that might be worth looking into. The result would not be a classic BCS superconductor: it's too hot, not in a solid lattice, depends on rather than excluding magnetic fields, depends on rather than breaking down with large currents, etc ad nauseum. But who knows?

Those are the main reasons not to expect condensed plasmoids to superconduct. The reasons to expect that they might are:

• Persistence. If a CP is in fact a microscopic current loop carrying kiloamps, it should have a high resistance (due to conducting channel width) even at the resistivity of copper, and a huge I^2R energy dissipation if R is anything other than 0. But they can last for hours.
• Quiescence. CPs can "go dark" and hide in cracks, crystal boundaries, and microscopic craters without emiting any energy, only to break up with a bang when conditions change.
• Downconversion of fusion energies. Dicke proposed the name "superradiance" for one-to-many quantum energy transfer 7 decades ago. It has recently been demonstrated, and there are no better theories I am aware of to explain the absence of high-energy nuclear reaction products in experiments. This phenomenon explicitly depends on coherence. See this talk for the latest.

To expand on the last point above, the idea is that in a quantum mechanically described interaction, it is possible to move a dollop of energy, even a large dollop, from one configuration of quantum states to another if various other things are right. Highly oversimplified, if you are fusing deuterium, each fusion gives you a helium nucleus and 24 MeV, which is way way too much to lodge in any individual particle. But if you have a coherent current of 24 million electrons which is a single coherent quantum object, you're only trying to bump each electron up by 1 eV, which doesn't seem like all that much! 

... and cold fusion

22. Lightning melts Metals; and I hinted in my Paper on that Subject, that I suspected it to be a cold Fusion (I do not mean a Fusion by Force of Cold, but a Fusion without Heat.)

-- Benjamin Franklin, second letter to Peter Collison dated July 29, 1750

[This is the third post in a series; the first is here.]

The man who coined the phrase "cold fusion" was none other than Benjamin Franklin, in connection with his experiments on electricity and lightning. The phrase is generally taken to mean that Franklin found static electricity capable of inducing changes in metal much like melting, but without producing the sensible heat that would normally have accompanied the process. As the foremost student of lightning of his day, there is a reasonable possibility he saw ball lightning or other plasmoid phenomena. We know that German physicist Georg Wilhelm Reichmann, attempting to replicate Franklin's famous kite experiment the following year, did. Briefly. "A glowing ball of charge traveled down the string, jumped to his forehead and killed him instantly - providing history with the first documented example of ball lightning in the process." (APS)

Observed ball lightnings tend to range from fist to furniture sized. This is probably more an observer selection effect than a physical one. We know that latter-day experiments by Bostick, Shoulders, Matsumoto, Adamenko, Jaitner, and others have produced condensed plasmoids with sizes (and characteristic tracks) range down to the 50 micron range, requiring microscopes to see their structure. 

Cold fusion, in Franklin's sense, definitely appears to be going on when a plasmoid touches down on to matter, be it metal or dielectric. Condensed plasmoids (hereinafter CPs) disrupt matter very much as super-highly charged ions do, by yanking electrons off atoms, removing bonds and causing the atoms to repel each other electrostatically. 

Here are two photos from Ken Shoulders' work showing holes made in lead glass and aluminum respectively by CPs.  

In these pictures, CPs have drilled through an aluminum coating and into a slab of alumina (Al2O3, a very hard ceramic and the primary constituent of ruby and sapphire), spewing alumina back out the holes in such a way as to form a patchy coating on the aluminum.

It's pretty clear that ionic disruption, not heat, is the causative agent here, so we have cold fusion in Franklin's sense. What about the more modern sense of nuclear reactions? Here is a micrograph of a similar hole in a deuterium-loaded palladium foil. Although most of the foil remained pure palladium, the gunk around the hole(s) evidenced significant amounts of silicon, calcium, and magnesium.

So what's going on? The theory is that CPs form when a spark, ranging from rubbing a cat and touching a doorknob to lightning, finds just the right conditions for a runaway ζ-pinch which magnetically squeezes the plasma to atomic scales. Considered in isolation, a current like that hanging in free space really wants to form a loop, since it's creating a major positive charge at one end and a negative one at the other, and the ends thus attract. When the ζ-pinch runs away it's capable of squeezing nuclei together close enough for tunneling to happen, and what happens then depends on what nuclei happen to have gotten trapped in there.

What happens then is problematical if only because there are so many possibilities depending on both the environment and the configuration of the CP. But it seems that in come cases, especially in metal, the CP can dig itself a "nest" which both stabilizes it and provides it with fusion fuel (e.g. deuterons with which a palladium electrode has been loaded, that seep out into the CP sustaining an ongoing reaction). Evidence for this is that electrodes that have exhibited cold fusion tend to be easier to start it up again than fresh ones, presumeably because the "nests" are already there and easier to form CPs in.

(Next post here)

Condensed plasmoids

 The second post in a series; the first is here. 

So a plasmoid is a (more-or-less) stable configuration of plasma, currents, and magnetic fields; the most well-know example is ball lightning. Plasmoids require energy to form, and typically emit energy, by glowing or ionizing matter around them; when the remaining energy is too small to maintain the conditions of the stable cofiguration, the plasmoid typically explodes, releasing all the rest of its energy at once.

Giant multi-billion experimental fusion reactors use extremely high-temperature plasmas in configurations as much like plasmoids as possible, but they are not technically plasmoids, because they do not self-sustain and require the input of substantial energy (and externally supplied magnetic fields) to operate. There are currently about 45 companies trying to build fusion reactors, up from 10 a decade ago. Fusion in plasmas has been achieved many times: the trick everyone is trying for is to get more energy out than you put in.

A condensed plasmoid, on the other hand, is something closer to the size of your hand than the Eiffel Tower. Indeed the ones that we think we have seen generating more energy than they lose are microscopic or not much bigger. Sometimes, if this interpretation is correct, they remain stable for days, generating substantial energy with no external energy input. How can this be if it is so difficult to get a big tokamak to do the same thing?

We believe that the key is that the condensed plasmoids are cold. Heat (and the big reactors are intentionally trying for millions of degrees) increases pressure, and thus fights against the squeeze of the ζ-pinch effect. If a plasmoid is microscopic, it will lose heat fast through radiation. Of course normally it would then simply revert to normal matter, like a spark in a bug-zapper. But if the right combination of (very high) current, (fairly low) pressure, chemistry, and so forth happens, you can get a runaway ζ-pinch which magnetically squeezes the conducting path to atomic scales, which in turn raises the magnetic force squeezing it to astronomical levels.

The resulting plasmoid is called "condensed" by Jaitner and his group; I think the choice of the word is inspired. Previous descriptions either don't capture the real dynamics of the phenomenon ("EVs", "charge clusters") or anything significant at all ("exotic vacuum objects," "strange radiation"). Condensation in the formation process reasonably describes the reduction of the conducting path to atomic dimensions, and not incidentally forces nuclei that have been captured by the excess of negative charge into considerably closer proximity than they could be found even in normal, solid, "condensed," matter. This is not your grandfather's plasma.

... and if it should turn out that the core current in a condensed plasmoid is in fact superconducting, the word "condense" is already used in the theory of superconductivity to refer to the same phenomenon.

Epistemic status check: condensed plasmoids are undeniably a real thing. They have been observed by many experimenters and were studied extensively by Kenneth Shoulders in the 80s (he called them "EVs"). If you wish to study them yourself, extensive and detailed information can be found in US patent US5018180A. (But be careful -- the Russian researchers call them "strange radiation" for a reason.) The physical theory and interpretation here are new in detail but phenomena suggesting nuclear activity, including elemental transmutation, radiation (including hard X-rays), and inexplicably large energy generation, have been experimentally verified again and again.

The result is a state where the nuclei are cold, by processes reminiscent of laser cooling in optical tweezers, but at the same time forced together close enough for fusion to occur. What then?

Normally you would expect that from fusion (of anything to the left of iron-56 in the curve of binding energy) you would get energetic nucleus fragments (protons, neutrons, alpha particles, etc) and serious gamma rays out as a result. You can fire basketballs into a trash can with a catapult but don't expect them to make a nice soft landing and sit there. Here's where we get to the second part of my revelations at IWAHLM-16 -- the progress in the quantum mechanics of down-conversion by the MIT team. What that means is that there are recognized pathways for a giant dollop of energy not to explode a nucleus the way it normally would, but to parcel out its energy to a host of smaller recipients, like the electrons forming the current of the plasmoid.

After this, it's all details. The devil is in them, of course, but key elements of the physics may be coming into sight. The condensation of the plasmoid is in a runaway mode until the electrons can't be squeezed any further. At that point the plasmoid is negatively charged and nuclei are attracted into it, where they may be squeezed close enough together to fuse. The plasmoid, which if it isn't technically superconducting in the condensed state is doing something quantum mechanical enough to act like it, supports the down-conversion dynamics. So each, or at at least enough of, the nuclear fusions add energy to the plasmoid current, which keeps it going or can even produce more energy than went in.

Once we get a solid understanding of the physics, our new energy revolution will be about where the Industrial Revolution was in 1643 when Torricelli invented the barometer. Technological progress moves faster now, though, so we might live to see some useful results. Like megawatt generators you can carry in a pocket that use (tiny amounts of) air as fuel.

[Next post here.]

Paradigm shift in cold fusion?

 Petrified with astonishment, Richard Seaton stared after the copper steam-bath upon which he had been electrolyzing his solution of “X,” the unknown metal. For as soon as he had removed the beaker the heavy bath had jumped endwise from under his hand as though it were alive. It had flown with terrific speed over the table, smashing apparatus and bottles of chemicals on its way, and was even now disappearing through the open window.

—E. E. “Doc” Smith, The Skylark of Space

Chapter 5 of "Flying Car" opens with this quotation from the iconic space opera. I then proceed to compare the rambunctious events in the novel to the almost-as-rambunctious events of the first few years of the cold fusion saga. There was enough of an amusing similarity to inspire the comparison -- in the novel, Seaton was an electrochemist doing electrolysis experiments with platinum-group metals, for example -- and to include the science fiction novel in the discussion of an extended episode of actual science.

But at this point it is worth our time to consider the differences. In real life, Fleischmann and Pons, after their original startling burn-through event and subsequent more careful experiments involving heat gain, continued doing exploratory experiments, with spotty results. Other experimenters got similarly spotty results, occasionally getting excess heat and sometimes, as with Mizuno in Japan, run the current for months and get nothing, then suddenly get 10 times as much heat out as you were putting in, and sometimes the reactor would produce power for days even after the input power was turned off. There were even, thankfully rare, explosions.

Mizuno's "Heat after Death" reactor

In the novel, by contrast, Our Hero does not continue experiments but instead sits down to work out the basic theory of the thing before fooling around with it. Meanwhile the bad guys try to steal the discovery, run off and do experiments without any theoretical understanding, and blow themselves up. 

Sorry, but that's the difference between a SF novel and reality. In real life, science proceeds by the slow, groping-in-the-dark methods of the experimenter. The first version of "Flying Car" came with an appendix listing all the experimenters who had died in the quest for flying machines. The names filled a page. It is only after the accumulation of knowledge from experiment that we know enough to form useful models. Even Newton, genius though he certainly was, needed both the painstaking observations of Tycho and regularities worked out by Kepler to make the breakthrough into a modern understanding of solar system dynamics.

People have been trying to understand cold fusion phenomena for 35 years and don't seem to have made an awful lot of progress. A lot of detail has been collected but nothing you could call a set of generally applicable organizing principles. It's not that there isn't a theory; it is that there are hundreds of theories and none of them has shown enough overall explanatory power to displace the others.

It's my experience that when you get into a situation like this, it's because you just have the wrong model of what's going on, and you aren't interpreting your evidence appropriately. God isn't sending lightning to strike your church because the congregation is sinning; Maxwell's equations are sending lightning to strike your church because it is the tallest pointed object in the area. All the squabbling over who's sinning the most is, to steal a phrase, not even wrong.

 Thomas Kuhn would have said that anomalies are accumulating and a paradigm shift is eminent. 

I recently attended IWAHLM-16 (a conference in memoriam of Bill Collis) in Strasbourg. The workshops are perhaps second to the main ICCF conference series. I hadn't expected much, but Strasbourg has 99 Michelin-rated restaurants and it fit into my schedule; I thought I would get to say Hi to some old friends. 

I was pleasantly surprised. There were two new things, one of which I had known about and one I had missed, even though if I had been paying close attention I might have picked up on. 

First, the one I knew about, is Peter Hagelstein's (an MIT physics prof) quantum mechanics-based theories of how a fusion (or other nuclear) reaction might spread its resulting energy out over a (very) large number of things, such as a lot of atoms' motions comprising heat, instead of spewing protons and neutrons and gamma rays around as happens when you achieve fusion in a particle accelerator. This work had advanced significantly, there is a whole group of grad students and researchers involved in it, and a "big paper" is expected soon. 

The other new thing wasn't really new, and indeed I had been seeing it for some time but filtering it out. Cold fusion tends to attract enough people with way-out theories, so much that you would waste way too much time if you tried to seriously consider all of them. So one develops mental filters to make a first cut and allow you to spend your time thinking about the things that have a greater chance of turning into useful and explanatory theories.

Among the things I had been filtering out were "strange radiation" and "exotic vacuum objects" or "EVOs". They might as well have been saying "UFOs" as far as I was concerned.  So before I proceed, lest you have the same reaction, let's state a few things that are well-known, incontrovertible, mainstream physics.

• Plasma is the 4th state of matter, and indeed almost all the matter in the universe is plasma: stars. Lightning is also plasma. 
• Fusion occurs in plasma; indeed most of the mainstream experimental fusion reactors use plasma.
• The Z-pinch (sometimes ζ-pinch) effect is a phenomenon of bog-standard electromagnetic theory: although stationary like charges repel, moving charges (currents) in parallel produce magnetic fields that tend to attract. (Which force wins depends on details.) The ζ-pinch effect is used in virtually every plasma-based experimental fusion reactor.

And here are some things that are not so well-known, but which are well-supported by historical and experimental evidence:

• A plasmoid is a (more-or-less) stable configuration of plasma, currents, and magnetic fields; the most well-know example is ball lightning.
• Plasmoids can be created in the laboratory in sizes ranging from ball lightning down to microscopic. This has been done by multiple researchers over the 20th century, all of whom named them something different!
• Microscopic plasmoids in contact with metal surfaces leave characteristic craters and other surface deformations.
• Working, i.e. heat-producing, cold fusion experiments are typically found to have left similar stigmata on electrode surfaces.
• In a series of successful cold fusion experiments at SPAWAR, IR videos of the electrodes showed that the process was characterized by the twinkling of thousands of points of heat on the electrode surface.

The hypothesis is that microscopic plasmoids form an environment that supports fusion. I had seen the talk by Gordon linked above, at ICCF-21, and a talk by Jaitner at ICCF-22 laying out the hypothesis, but hadn't made the connection. It wasn't until I ran into Jaitner again at IWAHLM-16, when he had moved from theory to experimental results, that I made the connection.

Will all this constitute a paradigm shift? I think it could. Condensed plasmoids could explain why fusion occurs and the MIT down-conversion quantum mechanics why it provides energy in a way that keeps the plasmoid going without external power. (Why "condensed"? Next post (here), or just watch the talk!)

Fusion, the Fuel of the Future

 Did it ever occur to you that you could run an ordinary car engine -- cylinders, pistons, crankshaft and all -- with no fuel? 

No problem! You just install really heavy-duty spark plugs, and as the piston reaches the top of the compression stroke in each cylinder, fire off a huge spark, think of it as a small bolt of lightning. The air doesn't care where the energy comes from, just that it gets hot and expands to push the piston back down. As long as you dump as much energy in through the spark as you would have gotten from oxidizing fuel, the motor hums right along. 

Of course, this would be a horribly inefficient way to use electricity to turn a shaft; existing electric motors are much much better. The point of the mental exercise is to get you to compare the amount of energy used by the spark and that produced by burning the fuel. Realize that they might actually be comparable.

In fact, that's what is going on in pretty much all current fusion experiments. So far, nobody has managed to get as much energy out of the fuel as they put in in the spark. The latest big buzz from the JET torus managed about 70%. However, with the current amount of interest and investment, it seems likely that someone will hit  100% (or exceed! 101%!) sometime this decade.

When you hear about that, what will it mean? 

Nice bit of science, not so much for energy. Let's go back to the car engine. 70% or so of the energy produced by the burning fuel is simply thrown away as heat. Then of the mechanical energy you get, you use a lot of it overcoming friction in the engine, turning a generator to produce more sparks, even pumping coolant through the engine so it doesn't melt. 

We don't really know in its fullness how the energy from the fusion reactor is going to be turned into (say) electric power, but we can say with fair assurance that it's not going to be cheap, easy, or efficient. So even when the magic 100% figure gets achieved (and for more extensive times than 5 seconds!), it's virtually certain that you have at least another decade to wait before there is any fusion power flowing on the grid.

Foo Fighters

 Interesting post from Robin Hanson about how the universe may be full of incompetent aliens who may have randomly been sending UFOs to us for centuries but never got anything done. I agree with most of Robin's points about how our power structures are enormously wasteful, sort of like the ancient Chinese empires, and we shouldn't really expect our civilization, or the aliens, to do any better on the average.

He uses the "Foo Fighters" seen by WWII aviators as an example of something that may have been alien craft:

... pilots flying over Germany by night reported seeing fast-moving round glowing objects following their aircraft. The objects were variously described as fiery, and glowing red, white, or orange. Some pilots described them as resembling Christmas tree lights and reported that they seemed to toy with the aircraft, making wild turns before simply vanishing. Pilots and aircrew reported that the objects flew formation with their aircraft and behaved as if under intelligent control, but never displayed hostile behavior. However, they could not be outmaneuvered or shot down. 

The main problem with this as an alien spacecraft, though, is that I have seen one of these myself.

And I know what it is.

It was a couple of decades ago. We were on a cruise ship, sailing up the Canadian/Alaskan Inner Passage, about a night out of Skagway. We had splurged for the trip, so we had a top-deck cabin with a balcony (and a butler). Just about bedtime, on the night in question, I stepped out onto the balcony for a breath of fresh air before turning in.

It was slightly overcast and very still. I could see shore lights in the distance, and the ship made steady progress through a sea that was almost like glass. There was no moon.

I looked forward. There was a glowing disc hovering maybe 200 feet over the bow. It dashed out in front, almost like a dog running in front of a car. It came back. It danced around. It made circles around the ship. It stopped overhead, never quite standing still, but I got a good look at it. Featureless, round, glowing softly.

It was completely silent.

I watched it for maybe 10 or 15 minutes. Then it disappeared. I went back in, mentioned to my wife that I had just seen the most amazing thing, and went to bed.

What could it have been? The only thing I have seen even vaguely like it was the spot from a searchlight dancing on the bottom of a cloud layer. But the ship didn't have the right kind of searchlight, it couldn't have done the fine dancing, it would have changed shape as it tilted low to go far out, and the beam would have raked the deck as the spot dashed from stem to stern and I would have seen it. Nothing like that happened.

But it was a clue. Something like the searchlight had happened, but not from below. The overcast layer was thin, of a kind I have seen many times flying. We were in northern waters, and as it turned out, some people in Skagway had seen aurora that night.

We were on an enormous iron object, moving, and that does interesting things to the Earth's magnetic field. In particular, it can focus a tendril out of an otherwise diffuse electron flow, as seen here:

So the ship had gone through what would otherwise been a nearly invisible aurora borealis, and concentrated it into visibility as it pierced the thin cloud layer. If you've played with a plasma ball like this, you will be very familiar with the character of its motion and why it seemed to be interested in the ship.

And it sounds a lot like the descriptions of the "Foo Fighters."

A Complex Treasure

 In the wake of this recent work, there has been a resumption of the sporadic debate over which imaginary numbers are real (pun intended) or not. Not so much by mathematicians, who tend to believe that they discover, rather than inventing, the structures of thought they employ, but physicists, who tend to think of the math they use as a different order of being than the actual physical world they describe.

From a pragmatic point of view it doesn't matter. If you have various mental tools, use the one that works best. The best meta-rule is Ockham's Razor.

In that spirit, I thought I would revisit a cute little puzzle that is often used to show how complex numbers are a bit more simple, nifty, or appropriate than just plain pairs of coordinates for solving a problem. The problem has nothing to do with the deeper properties of the quantum field; it's about a treasure map. 

It goes like this:

You have come into possession of a chart from a pirate long dead. It shows the location of a small island in the Spanish Main, and on the back are directions to find the treasure. "Pace from the cairn to the ash tree, turn right and pace the same, driving a stake. Again from the cairn to the bay tree, turning left and pacing the same, and a stake. Midway between your stakes is the treasure to be found."

You get to the island and find the ash and bay trees. Unfortunately in the meantime the island has been visited by a gang of kleptotaphophiles, who stole all the stones of the cairn, leaving it unmarked. How can you find the treasure?

Or, since this is really a math puzzle, how can you use complex numbers to prove your solution is correct?

The trick with a math problem is often to gain an intuition as to what the solution is, and then use the tools you have to show it is right. 

In my experience you are much more likely to be taught how to use the tools, and less likely to be taught how to gain an intuition. With that in mind, let's look at the map.

On our island it just so happens that the bay and ash trees are on an exact east-west line, and are exactly two furlongs apart. (A mathematician would phrase that, "Without loss of generality we may assume ..."). 

Now here's the essence of gaining an intuition. Take boundary cases, cases where something goes to 0 or 1, anything to simplify the problem without changing it overall. In the case of the treasure map, for example, start with cases where you can easily see the answer without doing any numerical geometry.

Let's call the point midway between the trees "Zero" and see what would happen if it were the cairn.

Pacing and staking, we get a simple diagram that shows the treasure would be exactly one furlong due south of Zero. Okay, what's another way to simplify?

Just pick the cairn as being one of the trees. Then the pacings for that tree are of zero length, and you drive the stake right there. When you pace the other tree you get:

Whaddya know, one furlong due south of Zero. And obviously it works the same starting from the ash tree.

What else can we eliminate? How about the string between the stakes? If they are in the same place, the centerpoint, and thus the treasure, will be right there. Put the cairn at one furlong due north of Zero:

Yep, it's at the same spot, one furlong south. And for a final flourish, what if we put the cairn right on the treasure?

Well, by now you will have gained the intuition that wherever you put the cairn, the treasure will be in the same place. And you even know where the place is. 

You now have your conjecture, and can prove it fairly straightforwardly using complex numbers.

But while you are doing that, I will have jumped to a conclusion, dug up the treasure, and escaped.