Category Archives: Science: Physics, Astronomy, etc.

Change your underwear; of mites and men

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The underware bomber mites make it right.

Umar, the underwear bomber.

For those who don’t know it, the underwear bomber, Umar Farook Abdulmutallab, wore his pair of explosive underwear for 3 weeks straight before trying to detonate them while flying over Detroit in 2009. They didn’t go off, leaving him scarred for life. It’s quite possible that the nasty little mites that live in underwear stopped the underwear bomber. They are a main source of US allergens too.

Dust mite, skin, and pollen seen with a light microscope. Gimmie some skin.

Dust mite, skin, and pollen seen with a light microscope. Gimmie some skin.

If you’ve ever used an electron microscope to look at household objects, you’ll find them covered with brick-like flakes of dried out skin-cells: yours and your friends’. Each person sheds his or her skin every month, on average. The outer layer dries out and flakes off as new skin grows in behind it. Skin flakes are the single largest source of household dust, and if not for the fact that these flakes are the main food for mites, your house would be chock full of your left over skin. When sunlight shines in your window, you see the shimmer of skin-flakes hanging in the air. Under the electron microscope, the fresh skin flakes look like bricks, but mite-eaten skin flakes look irregular. Less common, but more busy are the mites.

The facial mite movie. They live on in us, about 1 per hair follicle, particularly favoring eyelashes. Whenever you shower, your shower with a friend.

The facial mite movie. They live on in us, about 1 per hair follicle, particularly favoring eyelashes. Whenever you shower, you shower with a friend.

Dry skin is mostly protein (keratin), plus cholesterol and squalene. This provides great nutrition for dust mites and their associated bacteria. In warm, damp environments, as in your underwear or mattress, these beasties multiply and eat the old skin. The average density of dust mites on a mattress is greater than 2500/gram of dust.[1]  The mites leave behind excrement and broken off mite-limbs: nasty bits that are the most common allergens in the US today.

An allergy to dust shows up as sneezing, coughing, clogged lungs, and eczema. The most effective cure is a high level of in-home hygiene; mites don’t like soap or dry air. You’ve go to mop and vacuum regularly. Clean and change your clothing, particularly your undergarments; rotate your mattresses, and shake the dust out of your bedding. Vacuuming is less-effective as a significant fraction of the nasties go through the filter and get spread around by the vacuum blower.

As it turns out, dust mites and their bacteria eat more than skin. They also eat dried body fluids, poop residue, and the particular explosive used by Umar Farook, pentaerythritol tetra nitrate, PETN (humans can eat and metabolize this stuff too — it’s an angina treatment). The mites turn PETN into less-explosive versions, plus more mites.

Mighty mites as seen with electron microscopy. They eat more than skin.

Mighty mites as seen with electron microscopy. They eat more than skin.

There are many varieties of mite living on and among us. Belly button mites, for example, and face mites as shown above (click on the image to see it move). On average, people have one facial mite per hair follicle. It’s also possible that the bomber was stopped by poor quality control engineering and not mites at all. Religion tends to be at odds with a science like quality control, and followers tend to put their faith in miracles.

Chigger turning on a dime

Chigger turning on a dime

larger than the dust mite is the chigger, shown at left. Chiggers leave visible bites, particularly along the underwear waste-band. There are larger-yet critters in the family: lice, bed bugs, crabs. Bathing regularly, and cleaning your stuff will rid yourself of all these beasties, at least temporarily. Keeping your hair short and your windows open helps too. Mites multiply in humid, warm environments. Opening the windows dries and cools the air, and blows out mite-bits that could cause wheezing. Benjamin Franklin and took air-baths too: walking around naked with the windows open, even in winter. It helped that he lived on the second floor. Other ways to minimize mite growth include sunlight, DOT (a modern version of DDT), and eucalyptus oil. At the very minimum, change your underwear regularly. It goes a long way to reduce dust embarrassing moments at the jihadist convention.

Dr. Robert E. Buxbaum, Sept 21, 2014. Not all science or life is this weird and wonderful, but a lot is, and I prefer to write about the weird and wonderful bits. See e.g. the hazards of health food, the value of sunshine, or the cancer hazard of living near a river. Or the grammar of pirates.

New mixed drink, the R°

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Earlier this week, R__ turned 21, the drinking age in most of the USA. As a gift to her, I thought I might invent a new mixed drink that would suit her taste, and make her birthday more special. My requirements: that it should be kosher, that it’s made with widely available ingredients; that it should be relatively sophisticated, that it should be lower in alcohol (a fatherly concern), and that it should taste good to her and the general public.

The R___: gin tonic and grenadine

The R°: gin, tonic , ice, and grenadine

What I came up with, is something I call,The R°. It’s a modification of one of the great drinks of the western world, the gin and tonic. My modification is to use less gin, and to use grenadine instead of the traditional squeeze of lime. As she gets older, she may want to increase the gin content. The recipe: put 2/3 shot gin in a 10 oz straight-sided glass. Fill the glass 2/3 full of ice, near-fill with tonic water, and add a dash of grenadine, 1/4 shot or so (I used Rose’s). Stir slightly so the pink color stays mostly on the bottom. The result is slightly sweeter than the traditional gin and tonic, kosher in almost all places (you’ve got to check, but generally true), fairly sophisticated, good-tasting, and a reminder of Israel, a country where pomegranates grow all over. If you order one at a place with black lights and doesn’t stir much,you’ll discover that the tonic water glows electric-blue.

The verdict: R__ liked it. My hope is that you will enjoy it too. As a literary note, grenade is French for pomegranate; hand grenades got their name because of the shape. This drink is also suitable for talk like a pirate day (September 19).

Sept 14, 2014. My only previous gastronomic post was a recipe to make great lemonade. For a song by my daughter, go here, or here. For a joke about a neutron walking into a bar, go here.

The speed of sound, Buxbaum’s correction

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Ernst Mach showed that sound must travel at a particular speed through any material, one determined by the conservation of energy and of entropy. At room temperature and 1 atm, that speed is theoretically predicted to be 343 m/s. For a wave to move at any other speed, either the laws of energy conservation would have to fail, or ∆S ≠ 0 and the wave would die out. This is the only speed where you could say there is a traveling wave, and experimentally, this is found to be the speed of sound in air, to good accuracy.

Still, it strikes me that Mach’s assumptions may have been too restrictive for short-distance sound waves. Perhaps there is room for other sound speeds if you allow ∆S > 0, and consider sound that travels short distances and dies out far from the source. Waves at these, other speeds might affect music appreciation, or headphone design. As these waves were never treated in my thermodynamics textbooks, I wondered if I could derive their speed in any nice way, and if they were faster or slower than the main wave? (If I can’t use this blog to re-think my college studies, what good is it?)

I t can help to think of a shock-wave of sound wave moving down a constant area tube of still are at speed u, with us moving along at the same speed as the wave. In this view, the wave appears stationary, but there is a wind of speed u approaching it from the left.

Imagine the sound-wave moving to the right, down a constant area tube at speed u, with us moving along at the same speed. Thus, the wave appears stationary, with a wind of speed u from the right.

As a first step to trying to re-imagine Mach’s calculation, here is one way to derive the original, for ∆S = 0, speed of sound: I showed in a previous post that the entropy change for compression can be imagines to have two parts, a pressure part at constant temperature: dS/dV at constant T = dP/dT at constant V. This part equals R/V for an ideal gas. There is also a temperature at constant volume part of the entropy change: dS/dT at constant V = Cv/T. Dividing the two equations, we find that, at constant entropy, dT/dV = RT/CvV= P/Cv. For a case where ∆S>0, dT/dV > P/Cv.

Now lets look at the conservation of mechanical energy. A compression wave gives off a certain amount of mechanical energy, or work on expansion, and this work accelerates the gas within the wave. For an ideal gas the internal energy of the gas is stored only in its temperature. Lets now consider a sound wave going down a tube flow left to right, and lets our reference plane along the wave at the same speed so the wave seems to sit still while a flow of gas moves toward it from the right at the speed of the sound wave, u. For this flow system energy is concerned though no heat is removed, and no useful work is done. Thus, any change in enthalpy only results in a change in kinetic energy. dH = -d(u2)/2 = u du, where H here is a per-mass enthalpy (enthalpy per kg).

dH = TdS + VdP. This can be rearranged to read, TdS = dH -VdP = -u du – VdP.

We now use conservation of mass to put du into terms of P,V, and T. By conservation of mass, u/V is constant, or d(u/V)= 0. Taking the derivative of this quotient, du/V -u dV/V2= 0. Rearranging this, we get, du = u dV/V (No assumptions about entropy here). Since dH = -u du, we say that u2 dV/V = -dH = -TdS- VdP. It is now common to say that dS = 0 across the sound wave, and thus find that u2 = -V2 (dP/dV) at const S. For an ideal gas, this last derivative equals, PCp/VCv, so the speed of sound, u= √PVCp/Cv with the volume in terms of mass (kg/m3).

The problem comes in where we say that ∆S>0. At this point, I would say that u2 = -V(dH/dV) = VCp dT/dV > PVCp/Cv. Unless, I’ve made a mistake (always possible), I find that there is a small leading, non-adiabatic sound wave that goes ahead of the ordinary sound wave and is experienced only close to the source caused by mechanical energy that becomes degraded to raising T and gives rise more compression than would be expected for iso-entropic waves.

This should have some relevance to headphone design and speaker design since headphones are heard close to the ear, while speakers are heard further away. Meanwhile the recordings are made by microphones right next to the singers or instruments.

Robert E. Buxbaum, August 26, 2014

In praise of openable windows and leaky construction

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It’s summer in Detroit, and in all the tall buildings the air conditioners are humming. They have to run at near-full power even on evenings and weekends when the buildings are near empty, and on cool days. This would seem to waste a lot of power and it does, but it’s needed for ventilation. Tall buildings are made air-tight with windows that don’t open — without the AC, there’s be no heat leaving at all, no way for air to get in, and no way for smells to get out.

The windows don’t open because of the conceit of modern architecture; air tight building are believed to be good design because they have improved air-conditioner efficiency when the buildings are full, and use less heat when the outside world is very cold. That’s, perhaps 10% of the year. 

No openable windows, but someone figured you should suffer for art

Modern architecture with no openable windows. Someone wants you to suffer for his/her art.

Another reason closed buildings are popular is that they reduce the owners’ liability in terms of things flying in or falling out. Owners don’t rain coming in, or rocks (or people) falling out. Not that windows can’t be made with small openings that angle to avoid these problems, but that’s work and money and architects like to spend time and money only on fancy facades that look nice (and are often impractical). Besides, open windows can ruin the cool lines of their modern designs, and there’s nothing worse, to them, than a building that looks uncool despite the energy cost or the suffering of the inmates of their art.

Most workers find sealed buildings claustrophobic, musty, and isolating. That pain leads to lost productivity: Fast Company reported that natural ventilation can increase productivity by up to 11 percent. But, as with leading clothes stylists, leading building designers prefer uncomfortable and uneconomic to uncool. If people in the building can’t smell an ocean breeze, or can’t vent their area in a fire (or following a burnt burrito), that’s a small price to pay for art. Art is absurd, and it’s OK with the architect if fire fumes have to circulate through the entire building before they’re slowly vented. Smells add character, and the architect is gone before the stench gets really bad. 

No one dreams of working in an unventilated glass box.

No one dreams of working in a glass box. If it’s got to be an office, give some ventilation.

So what’s to be done? One can demand openable windows and hope the architect begrudgingly obliges. Some of the newest buildings have gone this route. A simpler, engineering option is to go for leaky construction — cracks in the masonry, windows that don’t quite seal. I’ve maintained and enlarged the gap under the doors of my laboratory buildings to increase air leakage; I like to have passive venting for toxic or flammable vapors. I’m happy to not worry about air circulation failing at the worst moment, and I’m happy to not have to ventilate at night when few people are here. To save some money, I increase the temperature range at night and weekends so that the buildings is allowed to get as hot as 82°F before the AC goes on, or as cold as 55°F without the heat. Folks who show up on weekends may need a sweater, but normally no one is here. 

A bit of air leakage and a few openable windows won’t mess up the air-conditioning control because most heat loss is through the walls and black body radiation. And what you lose in heat infiltration you gain by being able to turn off the AC circulation system when you know there are few people in the building (It helps to have a key-entry system to tell you how many people are there) and the productivity advantage of occasional outdoor smells coming in, or nasty indoor smells going out.

One irrational fear of openable windows is that some people will not close the windows in the summer or in the dead of winter. But people are quite happy in the older skyscrapers (like the empire state building) built before universal AC. Most people are nice — or most people you’d want to employ are. They will respond to others feelings to keep everyone comfortable. If necessary a boss or building manager may enforce this, or may have to move a particularly crusty miscreant from the window. But most people are nice, and even a degree of discomfort is worth the boost to your psyche when someone in management trusts you to control something of the building environment.

Robert E. Buxbaum, July 18, 2014. Curtains are a plus too — far better than self-darkening glass. They save energy, and let you think that management trusts you to have power over your environment. And that’s nice.

Dr. Who’s Quantum reality viewed as diffusion

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It’s very hard to get the meaning of life from science because reality is very strange, Further, science is mathematical, and the math relations for reality can be re-arranged. One arrangement of the terms will suggest a version of causality, while another will suggest a different causality. As Dr. Who points out, in non-linear, non-objective terms, there’s no causality, but rather a wibbly-wobbely ball of timey-wimey stuff.

Time as a ball of wibblely wobbly timey wimey stuff.

Reality is a ball of  timey wimpy stuff, Dr. Who.

To this end, I’ll provide my favorite way of looking at the timey-wimey way of the world by rearranging the equations of quantum mechanics into a sort of diffusion. It’s not the diffusion of something you’re quite familiar with, but rather a timey-wimey wave-stuff referred to as Ψ. It’s part real and part imaginary, and the only relationship between ψ and life is that the chance of finding something somewhere is proportional Ψ*|Ψ. The diffusion of this half-imaginary stuff is the underpinning of reality — if viewed in a certain way.

First let’s consider the steady diffusion of a normal (un-quantum) material. If there is a lot of it, like when there’s perfume off of a prima donna, you can say that N = -D dc/dx where N is the flux of perfume (molecules per minute per area), dc/dx is a concentration gradient (there’s more perfume near her than near you), and D is a diffusivity, a number related to the mobility of those perfume molecules. 

We can further generalize the diffusion of an ordinary material for a case where concentration varies with time because of reaction or a difference between the in-rate and the out rate, with reaction added as a secondary accumulator, we can write: dc/dt = reaction + dN/dx = reaction + D d2c/dx2. For a first order reaction, for example radioactive decay, reaction = -ßc, and 

dc/dt = -ßc + D d2c/dx2               (1)

where ß is the radioactive decay constant of the material whose concentration is c.

Viewed in a certain way, the most relevant equation for reality, the time-dependent Schrödinger wave equation (semi-derived here), fits into the same diffusion-reaction form:

dΨ/dt = – 2iπV/h Ψ + hi/4πm d2Ψ/dx2                (2)

Instead of reality involving the motion of a real material (perfume, radioactive radon, etc.) with a real concentration, c, in this relation, the material can not be sensed directly, and the concentration, Ψ, is semi -imaginary. Here, h is plank’s constant, i is the imaginary number, √-1, m is the mass of the real material, and V is potential energy. When dealing with reactions or charged materials, it’s relevant that V will vary with position (e.g. electrons’ energy is lower when they are near protons). The diffusivity term here is imaginary, hi/4πm, but that’s OK, Ψ is part imaginary, and we’d expect that potential energy is something of a destroyer of Ψ: the likelihood of finding something at a spot goes down where the energy is high.

The form of this diffusion is linear, a mathematical term that refers to equations where solution that works for Ψ will also work for 2Ψ. Generally speaking linear solutions have exp() terms in them, and that’s especially likely here as the only place where you see a time term is on the left. For most cases we can say that

Ψ = ψ exp(-2iπE/h)t               (3)

where ψ is not a function of anything but x (space) and E is the energy of the thing whose behavior is described by Ψ. If you take the derivative of equation 3 this with respect to time, t, you get

dΨ/dt = ψ (-2iπE/h) exp(-2iπE/h)t = (-2iπE/h)Ψ.               (4)

If you insert this into equation 2, you’ll notice that the form of the first term is now identical to the second, with energy appearing identically in both terms. Divide now by exp(-2iπE/h)t, and you get the following equation:

(E-V) ψ =  -h2/8π2m d2ψ/dx2                      (5)

where ψ can be thought of as the physical concentration in space of the timey-wimey stuff. ψ is still wibbly-wobbley, but no longer timey-wimey. Now ψ- squared is the likelihood of finding the stuff somewhere at any time, and E, the energy of the thing. For most things in normal conditions, E is quantized and equals approximately kT. That is E of the thing equals, typically, a quantized energy state that’s nearly Boltzmann’s constant times temperature.

You now want to check that the approximation in equation 3-5 was legitimate. You do this by checking if the length-scale implicit in exp(-2iπE/h)t is small relative to the length-scales of the action. If it is (and it usually is), You are free to solve for ψ at any E and V using normal mathematics, by analytic or digital means, for example this way. ψ will be wibbely-wobbely but won’t be timey-wimey. That is, the space behavior of the thing will be peculiar with the item in forbidden locations, but there won’t be time reversal. For time reversal, you need small space features (like here) or entanglement.

Equation 5 can be considered a simple steady state diffusion equation. The stuff whose concentration is ψ is created wherever E is greater than V, and is destroyed wherever V is greater than E. The stuff then continuously diffuses from the former area to the latter establishing a time-independent concentration profile. E is quantized (can only be some specific values) since matter can never be created of destroyed, and it is only at specific values of E that this happens in Equation 5. For a particle in a flat box, E and ψ are found, typically, by realizing that the format of ψ must be a sin function (and ignoring an infinity). For more complex potential energy surfaces, it’s best to use a matrix solution for ψ along with non-continuous calculous. This avoids the infinity, and is a lot more flexible besides.

When you detect a material in some spot, you can imagine that the space- function ψ collapses, but even that isn’t clear as you can never know the position and velocity of a thing simultaneously, so doesn’t collapse all that much. And as for what the stuff is that diffuses and has concentration ψ, no-one knows, but it behaves like a stuff. And as to why it diffuses, perhaps it’s jiggled by unseen photons. I don’t know if this is what happens, but it’s a way I often choose to imagine reality — a moving, unseen material with real and imaginary (spiritual ?) parts, whose concentration, ψ, is related to experience, but not directly experienced.

This is not the only way the equations can be rearranged. Another way of thinking of things is as the sum of path integrals — an approach that appears to me as a many-world version, with fixed-points in time (another Dr Who feature). In this view, every object takes every path possible between these points, and reality as the sum of all the versions, including some that have time reversals. Richard Feynman explains this path integral approach here. If it doesn’t make more sense than my version, that’s OK. There is no version of the quantum equations that will make total, rational sense. All the true ones are mathematically equivalent — totally equal, but differ in the “meaning”. That is, if you were to impose meaning on the math terms, the meaning would be totally different. That’s not to say that all explanations are equally valid — most versions are totally wrong, but there are many, equally valid math version to fit many, equally valid religious or philosophic world views. The various religions, I think, are uncomfortable with having so many completely different views being totally equal because (as I understand it) each wants exclusive ownership of truth. Since this is never so for math, I claim religion is the opposite of science. Religion is trying to find The Meaning of life, and science is trying to match experiential truth — and ideally useful truth; knowing the meaning of life isn’t that useful in a knife fight.

Dr. Robert E. Buxbaum, July 9, 2014. If nothing else, you now perhaps understand Dr. Who more than you did previously. If you liked this, see here for a view of political happiness in terms of the thermodynamics of free-energy minimization.

17+ years of no climate change

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Much of the data underlying climate change is bad, as best I can tell, and quite a lot of the animosity surrounding climate legislation comes from the failure to acknowledge this. Our (US) government likes to show the climate increasing at 4-6°C/century, or .05°C/year, but this is based on bad data of average global temperatures, truncated conveniently to 1880, and the incorrect assumption that trends always continue — a bad idea for stock investing too. We really don’t have any good world-wide temperature going back any further the 1990s, something the Canadian ice service acknowledges (see chart below) but we do not. Worse yet, we adjust our data to correct for supposed errors.

Theory vs experiment in climate change data

Theory vs experiment in climate change data; 17 years with no change.

High quality observations begin only about 10 years ago, and since then we have seen 17+ years of no significant climate change, not the .05°C per year predicted. Our models predicted an ice-free Arctic by 2013, but we had one of the coldest winters of the century. Clearly the models are wrong. Heat can’t hide, and in particular it can’t hide in the upper atmosphere where the heat is supposed to be congregating. The predictive models were not chaotic, and weather is, but instead show regular, slow temperature rises based on predictions of past experimental data.

In Canada and Australia, the climate experts are nice enough to put confidence bars on the extrapolated data before publishing it. Some researchers are also nice enough to provide data going back further, to late Roman times when the weather was really warm, or 20,000 years ago, when we had an ice age (it’s unlikely that the ice age ended because of automobile traffic).

Canada's version of Ice coverage data. The grey part is the error bar. Canada is nice enough to admit they know relatively little of what the climate was like in the 70s and 80s. We do not.

Canada’s version of Ice coverage data. The grey part is the error bar. Canada is nice enough to admit they don’t know what it was like in the 70s and 80s. We do not.

So what’s so wrong about stopping US coal use, even if it does not cause global warming. For one, it’s bad diplomatically — it weakens us and strengthens countries that hate us (like Iran), and countries like China that burn lots of coal and really pollute the air. It also diverts the US from real air pollution and land use discussions. If you want less air pollution, perhaps nuclear is the way to go. Finally, there you have to ask, even if we could adjust the earth’s temperature at will, who would get control of the thermostat? Who would decide if this summer should be warm or cold, or who should get rains, or sun. With great power comes great headaches.

Robert Buxbaum, June 21, 2014

American education how do we succeed?

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As the product of a top American college, Princeton University, I see that my education lacks in languages and history compared to Europeans. I can claim to know a little Latin and a little Greek, like they do, but I’m referring to Manuel Ramos and Stanos Platsis, two short people, one of Spanish descent, the other of Greek.

Americans hate math.

Americans hate math.

It was recently reported that one fourth of college-educated Americans did not know that the earth spun on an axis, a degree of science ignorance that would be inconceivable in any other country. Strange to say, despite these lacks, the US does quite well commercially, militarily, and scientifically. US productivity is the world’s highest. Our GNP and GNP per capita too is higher than virtually any other country (we got the grossest national product). How do we do it with so little education?

One part of US success is clearly imported talent, Immigration. We import Nobel chemists, Russian dancers, and German rocket scientists but we don’t import that many. They help our per-capita GNP, but the majority of our immigrants are more in the wretched refuse category. Even these appear to do better here than the colleagues they left behind. Otto von Bismark once joked that, “God protects children, drunks, and the United States of America.” But I’d like to suggest that our success is based on advantages our outlook our education provides for our more creative citizens.

Most of our successful businesses are not started by the A students, but by the C student who is able to use the little he (or she) knows. Consider the simple question of whether the earth goes round the sun. It’s an important fact, but only relevant if you can use it, as Sherlock Holmes points out. I suspect that few Europeans could use the knowledge that the earth spins (try to think of some applications; at the end of this essay I’ll provide some).

Benjamin Jowett. His students included the heads of 6 colleges and the head of Eaton

Benjamin Jowett, Master of Balliol College, Oxford.

A classic poem about European education describes Benjamin Jowett, shown at right. It goes: “The first come I, my name is Jowett. There is no knowledge, but that I know it. I am master of this college. What I don’t know isn’t knowledge.” Benjamin Jowett was Master of Balliol College, Oxford. By the time he died in 1893, his ex-student pallbearers included the heads of 6 colleges, and the head of Eaton. Most English heads of state and industry were his students directly or second-hand. All learned a passing knowledge of Greek, Latin, Plato, law, science, theology, classics, math, rhetoric, logic, and grammar. Only people so educated were deemed suited to run banks or manage backward nations like India or Rhodesia. It worked for a while but showed its limitations, e.g. in the Boer Wars.

In France and continental Europe the education system is similar to England’s under Jowett. There is a fixed set of knowledge and a fixed rate to learn it. Government and industry jobs go largely to those who’ve demonstrated their ability to give the fixed, correct answers to tests on this knowledge. In schools across France, the same page is turned virtually simultaneously in the every school– no student is left behind, but none jump ahead either. As new knowledge is integrated, the approved text books are updated and the correct answers are adjusted. Until then, the answers in the book are God’s truth, and those who master it can comfort themselves to have mastered the truth. The only people hurt are the very few dummies who see a new truth a year before the test acknowledges it. “College is a place where pebbles are polished but diamonds are dimmed.” The European system appears to benefit the many, providing useful skills (and useless tidbits) but it is oppressive to many others with forward-thinking, imaginative minds. The system appears to work best in areas that barely change year-to-year like French grammar, geometry, law, and the map of Europe. It does not work so well in music, computers, or the art of war. For these students, schooling is “another brick in the wall. For these students, the schools should teach more of how to get along without a teacher.

The American approach to education leans towards independence of thought, for good or bad. American graduates can live without the teacher, but leave school knowing no language but English, hardly and maths or science, hardly any grammar, and we can hardly find another country on a map. Teachers will take incorrect answers as correct as a way to build self-esteem, so students leave with the view that there is no such thing as truth. This model works well in music, engineering, and science where change is fast, creativity is king, and nature itself is a teacher. American graduate-schools are preeminent in these areas. In reading, history and math our graduates might well be described as galumphing ignorants.

Every now and again the US tries to correct this, by the way, and join the rest of the world. The “no child left behind” movement was a Republican-led effort to teach reading and math on the French model. It never caught on. Drugs are another approach to making American students less obstreperous, but they too work only temporarily. Despite these best efforts, American graduates leave school ignorant, but not stupid; respectful of those who can do things, and suspicious of those with lengthy degrees. We survive as managers of the most complex operations with our bumptious optimism and distain for hierarchy. As viewed from abroad, our method is to greet colleagues in a loud, cheerful voice, appoint a subordinate to “get things done,” and then get in the way until lunchtime.

In any moment of decision, the best thing you can do is the right thing, the next bet thing is the wrong thing, and the worst thing you can do is nothing. An American attitude that sometimes blows up, but works surprisingly well at times.

Often the inability to act is worse than acting wrong.

The American-educated boss will do some damage by his ignorance but it is no more than  comes from group-think: non-truths passed as truths. America stopped burning witches far sooner than Europe, and never burned Jews. America dropped nobles quicker, and transitioned to electric lights and motor cars quicker, perhaps because we put less weight on what nobles and universities did.

European scholars accepted that nobility gave one a better handle on leadership, and this held them back. Since religion was part of education, they accepted that state should have an established religion: Anglican, in England, Catholicism in France; scientific atheism now. They learned and accepted that divorce was unnecessary and that homosexuality should be punished by prison or worse. As late as the early 60s, Turing, the brilliant mathematician and computer scientist, was chemically castrated as a way to cure his homosexuality. In America our “Yankee ingenuity,” as we call it, had a tendency to blow up, too (prohibition, McCarthyism, and disco), but the problems resolved relatively soon. “Ready, fire, aim” is a European description of the American method. It’s not great, but works after a fashion.

The best option, I think, is to work together with those from “across the pond.” It worked well for us in WWI, WWII, and the American Revolution, where we benefitted from the training of Baron Von Steuben, for example. Heading into the world cup of football (fifa soccer) this week, we’re expected to lose badly due to our lack of stars, and general inability to pass, dribble, or strategize. Still, we’ve got enthusiasm, and we’ve got a German coach. The world’s bookies give us 0.05% odds, but our chances are 10 times that, I’d say: 5%. God protects our galumphing side of corn-fed ignorants when, as in the Revolution, it’s attached to German coaching.

Some practical aspects of the earth spinning: geosynchronous satellites (they only work because the earth spins), weather prediction (the spin of hurricanes is because the earth spins), cyclone lifting. It amazes me that people ever thought everything went around the earth, by the way; Mercury and Venus never appear overhead. If authorities could have been so wrong about this for so long, what might they be wrong about today?

Dr. Robert Buxbaum, June 10, 2014 I’ve also written about ADHD on Lincoln’s Gettysburg Address, on Theodore Roosevelt, and how he survived a gun shot.

Buddhists, Hindus and dentists joke

At the dentists’ office, Buddhist and Hindu monks don’t need anesthesia to have their teeth worked on. They transcend dental medication.

It’s funny because it’s a 3 word pun, and because there is something magical about the ability of people to conquer pain through meditation.

Focussed meditation can keep you from worry and other pain.

Focused meditation can keep you from worry and some physical pain. As for thugs, that’s more controversial. It’s possible that laughter, or looking at a spot will do as much. Gahan Wilson

The types of meditation, as I understand it, are two which are four. The two are focused and non-focused. focused meditation is supposed to allow you to conquer pain, both physical and spiritual. You concentrate on your breathing, or some other rhythmic action and thought; and whenever you realize that your mind is wandering you bring it back. A popular version is called square breathing: you breath in, hold, breath out, hold, etc. In time there is a sense of calm with the world. In theory, you can transcend dental medication, but I use the normal western practice of Novocaine plus gas. Meditation practitioners claim that directed meditation can also protect you from villains and bring peace in the world; I suspect that’s true, but also suspect that humor, or staring at a spot will do as much. I suspect that Dr Seuss has done wonders for peace in the world.

The second major version of mediation is non-focused; it can bring enlightenment if you use it right. You repeat a mantra slowly and let your mind wander along some general paths. The classic incantatory mantra is OM, and the classic paths include: what am I doing with my life, imagine a stick with one end, what is the sound of a hand clapping. The enlightenment that is supposed to arise is supposed to promote non-violence, charity, and a sense of oneness with the all. In general, I’ve found that letting one’s mind wander is a great way to solve difficult problems and to help one decide whether certain situations are worth being involved with. To the extent I’ve used a mantra, it’s versions of “radiator not leaking, mind leaking,” or “computer solution not unstable, mind unstable.” In the calm of realizing there is a solution, I’ve generally been able to find a solution.

Enlightenment can be as simple as realizing that you're there already or that you shouldn't manage a country that's unlike you and dislikes you.

Enlightenment can be as simple as realizing that you’re there already.

As for the other 2 types of meditation, it depends. To some, it involves rocking to the sound of the one hand clapping (or not). To some, it’s realizing you’re there already, or that you really don’t want to get involved in an Asian war to defend and manage a country that’s completely unlike yours, and that dislikes yours as well, or that it’s OK to use Novocaine and gas when you have your teeth worked on. That’s what they are there for.

Robert E. Buxbaum, May 24, 2014. Some wisdom from the Jewish mystics: Wherever you go, there you are, as for your baggage, who knows? Tea, with the first sip joy, with the second, satisfaction, with the third, Danish.

If hot air rises, why is it cold on mountain-tops?

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This is a child’s question that’s rarely answered to anyone’s satisfaction. To answer it well requires college level science, and by college the child has usually been dissuaded from asking anything scientific that would likely embarrass teacher — which is to say, from asking most anything. By a good answer, I mean here one that provides both a mathematical, checkable prediction of the temperature you’d expect to find on mountain tops, and one that also gives a feel for why it should be so. I’ll try to provide this here, as previously when explaining “why is the sky blue.” A word of warning: real science involves mathematics, something that’s often left behind, perhaps in an effort to build self-esteem. If I do a poor job, please text me back: “if hot air rises, what’s keeping you down?”

As a touchy-feely answer, please note that all materials have internal energy. It’s generally associated with the kinetic energy + potential energy of the molecules. It enters whenever a material is heated or has work done on it, and for gases, to good approximation, it equals the gas heat capacity of the gas times its temperature. For air, this is about 7 cal/mol°K times the temperature in degrees Kelvin. The average air at sea-level is taken to be at 1 atm, or 101,300  Pascals, and 15.02°C, or 288.15 °K; the internal energy of this are is thus 288.15 x 7 = 2017 cal/mol = 8420 J/mol. The internal energy of the air will decrease as the air rises, and the temperature drops for reasons I will explain below. Most diatomic gases have heat capacity of 7 cal/mol°K, a fact that is only explained by quantum mechanics; if not for quantum mechanics, the heat capacities of diatomic gases would be about 9 cal/mol°K.

Lets consider a volume of this air at this standard condition, and imagine that it is held within a weightless balloon, or plastic bag. As we pull that air up, by pulling up the bag, the bag starts to expand because the pressure is lower at high altitude (air pressure is just the weight of the air). No heat is exchanged with the surrounding air because our air will always be about as warm as its surroundings, or if you like you can imagine weightless balloon prevents it. In either case the molecules lose energy as the bag expands because they always collide with an outwardly moving wall. Alternately you can say that the air in the bag is doing work on the exterior air — expansion is work — but we are putting no work into the air as it takes no work to lift this air. The buoyancy of the air in our balloon is always about that of the surrounding air, or so we’ll assume for now.

A classic, difficult way to calculate the temperature change with altitude is to calculate the work being done by the air in the rising balloon. Work done is force times distance: w=  ∫f dz and this work should equal the effective cooling since heat and work are interchangeable. There’s an integral sign here to account for the fact that force is proportional to pressure and the air pressure will decrease as the balloon goes up. We now note that w =  ∫f dz = – ∫P dV because pressure, P = force per unit area. and volume, V is area times distance. The minus sign is because the work is being done by the air, not done on the air — it involves a loss of internal energy. Sorry to say, the temperature and pressure in the air keeps changing with volume and altitude, so it’s hard to solve the integral, but there is a simple approach based on entropy, S.

Les Droites Mountain, in the Alps, at the intersect of France Italy and Switzerland is 4000 m tall. The top is generally snow-covered.

Les Droites Mountain, in the Alps, at the intersect of France Italy and Switzerland is 4000 m tall. The top is generally snow-covered.

I discussed entropy last month, and showed it was a property of state, and further, that for any reversible path, ∆S= (Q/T)rev. That is, the entropy change for any reversible process equals the heat that enters divided by the temperature. Now, we expect the balloon rise is reversible, and since we’ve assumed no heat transfer, Q = 0. We thus expect that the entropy of air will be the same at all altitudes. Now entropy has two parts, a temperature part, Cp ln T2/T1 and a pressure part, R ln P2/P1. If the total ∆S=0 these two parts will exactly cancel.

Consider that at 4000m, the height of Les Droites, a mountain in the Mont Blanc range, the typical pressure is 61,660 Pa, about 60.85% of sea level pressure (101325 Pa). If the air were reduced to this pressure at constant temperature (∆S)T = -R ln P2/P1 where R is the gas constant, about 2 cal/mol°K, and P2/P1 = .6085; (∆S)T = -2 ln .6085. Since the total entropy change is zero, this part must equal Cp ln T2/T1 where Cp is the heat capacity of air at constant pressure, about 7 cal/mol°K for all diatomic gases, and T1 and T2 are the temperatures (Kelvin) of the air at sea level and 4000 m. (These equations are derived in most thermodynamics texts. The short version is that the entropy change from compression at constant T equals the work at constant temperature divided by T,  ∫P/TdV=  ∫R/V dV = R ln V2/V1= -R ln P2/P1. Similarly the entropy change at constant pressure = ∫dQ/T where dQ = Cp dT. This component of entropy is thus ∫dQ/T = Cp ∫dT/T = Cp ln T2/T1.) Setting the sum to equal zero, we can say that Cp ln T2/T1 =R ln .6085, or that 

T2 = T1 (.6085)R/Cp

T2 = T1(.6085)2/7   where 0.6065 is the pressure ratio at 4000, and because for air and most diatomic gases, R/Cp = 2/7 to very good approximation, matching the prediction from quantum mechanics.

From the above, we calculate T2 = 288.15 x .8676 = 250.0°K, or -23.15 °C. This is cold enough to provide snow  on Les Droites nearly year round, and it’s pretty accurate. The typical temperature at 4000 m is 262.17 K (-11°C). That’s 26°C colder than at sea-level, and only 12°C warmer than we’d predicted.

There are three weak assumptions behind the 11°C error in our predictions: (1) that the air that rises is no hotter than the air that does not, and (2) that the air’s not heated by radiation from the sun or earth, and (3) that there is no heat exchange with the surrounding air, e.g. from rain or snow formation. The last of these errors is thought to be the largest, but it’s still not large enough to cause serious problems.

The snow cover on Kilimanjaro, 2013. If global warming models were true, it should be gone, or mostly gone.

Snow on Kilimanjaro, Tanzania 2013. If global warming models were true, the ground should be 4°C warmer than 100 years ago, and the air at this altitude, about 7°C (12°F) warmer; and the snow should be gone.

You can use this approach, with different exponents, estimate the temperature at the center of Jupiter, or at the center of neutron stars. This iso-entropic calculation is the model that’s used here, though it’s understood that may be off by a fair percentage. You can also ask questions about global warming: increased CO2 at this level is supposed to cause extreme heating at 4000m, enough to heat the earth below by 4°C/century or more. As it happens, the temperature and snow cover on Les Droites and other Alp ski areas has been studied carefully for many decades; they are not warming as best we can tell (here’s a discussion). By all rights, Mt Blanc should be Mt Green by now; no one knows why. The earth too seems to have stopped warming. My theory: clouds. 

Robert Buxbaum, May 10, 2014. Science requires you check your theory for internal and external weakness. Here’s why the sky is blue, not green.

Getting rid of hydrogen

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Though most of my company’s business is making hydrogen or purifying it, or consulting about it, we also provide sorbers and membranes that allow a customer to get rid of unwanted hydrogen, or remove it from a space where it is not wanted. A common example is a customer who has a battery system for long-term operation under the sea, or in space. The battery or the metal containment is then found to degas hydrogen, perhaps from a corrosion reaction. The hydrogen may interfere with his electronics, or the customer fears it will reach explosive levels. In one case the customer’s system was monitoring deep oil wells and hydrogen from the well was messing up its fiber optic communications.

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Pd-coated niobium screws used to getter hydrogen from electronic packages.

For many of these problems, the simplest solution is an organic hydrogen getter of palladium-catalyst and a labile unsaturated hydrocarbon, e.g. buckminsterfullerene. These hydrogen getters are effective in air or inert gas at temperatures between about -20°C and 150°C. When used in an inert gas the organic is hydrogenated, there is a finite amount of removal per gram of sober. When used in air the catalyst promotes the water-forming reaction, and thus there is a lot more hydrogen removal. Depending on the organic, we can provide gettering to lower temperatures or higher. We’ve a recent patent on an organo-palladium gel to operate to 300°C, suitable for down-well hydrogen removal.

At high temperatures, generally above 100*C, we generally suggest an inorganic hydrogen remover, e.g. our platinum ceria catalyst. This material is suitable for hydrogen removal from air, including from polluted air like that in radioactive waste storage areas. Platinum catalyst works long-term at temperatures between about 0°C and 600°C. The catalyst-sorber also works without air, reducing Ce2O3 to CeO and converting hydrogen irreversibly to water (H2O). As with the organo-Pd getters, there is a finite amount of hydrogen removal per gram when these materials are used in a sealed environment.

Low temperature, Pd-grey coated, Pd-Ag membranes made for the space shuttle to remove hydrogen from the drinking water at room temperature. The water came from the fuel cells.

Low temperature, metal membranes made for NASA to remove H2 from  drinking water at room temperature.

Another high temperature hydrogen removal option is metallic getters, e.g. yttrium or vanadium-titanium alloy. These metals require temperatures in excess of 100°C to be effective, and typically do not work well in air. They are best suited for removing hydrogen a vacuum or inert gas, converting it to metallic hydride. The thermodynamics of hydriding is such that, depending on the material, these getters can extract hydrogen even at temperatures up to 700°C, and at very low hydrogen pressures, below 10-9 torr. For operation in air or at 100-400°C we typically provide these getters coated with palladium to increase the hydrogen sorption rate. A fairly popular product is palladium-coated niobium screws 4-40 x 1/4″. Each screw will remove over 2000 sec of hydrogen at temperatures up to 400°C. We also provide oxygen, nitrogen and water getters. They work on the same principle, but form metallic oxides or nitrides instead of hydrides.

Our last, and highest-end, hydrogen-removal option is to provide metallic membranes. These don’t remove the hydrogen as such, but transfer it elsewhere. We’ve provided these for the space shuttle, and to the nuclear industry so that hydrogen can be vented from nuclear reactors before it has a chance to build up and case damage or interfere with heat transfer. Because nothing is used up, these membranes work, essentially forever. The Fukushima reactor explosions were from corrosion-produced hydrogen that had no acceptable way to vent.

Please contact us for more information, e.g. by phone at 248-545-0155, or check out the various sorbers in our web-site. Robert Buxbaum, May 5, 2014.