A clever range extender for EVs

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Electric vehicles work well for short trips between places where you can charge with cheap electricity. Typically that’s trips from home to a nearby place of work, and to local shopping malls and theaters with low-cost charge spots. If you drive this way, you’ll pay about 3.2¢/mile for home electricity, instead of about 17¢/mile for gasoline transport (e.g. 24 mpg with $4/gallon gas). Using an EV also saves on oil changes, transmission, air filters, belts, etc., and a lot of general complexity. Battery prices are still high, but much lower than they were even a few years ago.

The 10 kW Aquarius Engine is remarkably small and light, about 10kg (22 lb).

EVs are less attractive for long trips, especially in the cold. Your battery must provide the heat, as there is no waste heat from the engine. Expect to have to recharge every 200 -250 miles, or perhaps twice in the middle of a long trip. Each charge will take a half-hour or more, and fast charging on the road isn’t low cost. Expect to pay about 15¢/mile, nearly as much as for gasoline. See my full comparison of the economics here.

One obvious solution is to have two cars: a short commuter and an EV. Another solution is a hybrid. The Toyota’s Prius and the Chevy Volt were cutting edge in their day, but people don’t seem to want them. These older hybrids provided quick fill-ups, essentially infinite range, and about double the gas milage of a standard automobile, 30-45 mpg. The problem is you have even more complexity and maintenance than with even a gas automobile.

Aquarius liner engine as a range extender

I recently saw a small, simple, super-efficient (they say) gas engine called Aquarius. It provides 9.5 kW electric output and weighs only 22 lbs (10 kg), see picture above. A Tesla S uses about 16 kW during highway driving, implying that this engine will more than double the highway range of a Tesla S at minimal extra weight and complexity. It also removes the fear of being stranded on the highway, far from the nearest charge-station.

The energy efficiency is 34%, far higher than that for normal automobile engines, but fairly typical of floating piston linear engines. The high efficiency of these engines is partly due to the lack of tapper valves, risers, crank-shaft, and partially due to the fact that the engine always runs at its maximum power. This is very close to the maximum efficiency point. Most car engines are over sized (200 hp or so) and thus must run at a small fraction of their maximum power. This hurts the efficiency, as I discuss here. The Aquarius Engine makes electricity by the back-forth motion of its aligner rods moving past magnetic stator coils. Slots in the piston rod and in the side of the cylinder operate as sliding valves, like in a steam engine. First versions of the Aquarius Engine ran on hydrogen, but the inventors claim it can also run on gasoline, and presumably hythane, my favorite fuel, a mix of hydrogen and natural gas.

At the moment shown, slit valves in the piston rod are open to both cylinder chambers. The explosion at left will vent to the exhaust at left and out the manifold at top. The sliding valve is currently sending fresh air into the cylinder at right, but will soon send it into both cylinders to help scavenge exhaust and provide for the next cycle; engine speed and impression are determined by the mass of the piston.

A video is available to show the basic operation (see it here). The drawing at right is from that video, modified by me. Air is drawn into the engine through a sliding valve at the middle of the cylinder. The valve opens and closes depending on where the piston is. At the instant shown in the picture, the valve is open to the right. Air enters that chambered is likely exiting through slits in the hollow piston rod. It leaves through the manifold t the top, pushing exhaust along with it. When the piston will have moved enough, both the slits and the intake will close. The continued piston motion (inertially driven) will compress the air for firing. After firing, the piston will move left, generating electricity, and eventually opening the slit-valve in the piston to allow the exhaust to leave. When it moves a little further the intake will open.

The use of side-opening exhaust valves is a novelty of the “Skinner UniFlow” double-acting, piston steam engines, seen on the Badger steamship on Lake Michigan. It’s one of my favorite steam engine designs. Normally you want a piston that is much thicker than the one in the drawing. This option is mentioned in the patent, but not shown in the drawing.

Aquarius is not the only company with a free-piston range extender. Toyota built a free-piston extender of similar power and weight; it was more complex but got higher efficiency. It has variable compression though, and looks like a polluter. (the same problems might affect the Aquarius) They dropped the project in 2014. Deutsch Aerospace has a two headed version that’s more powerful, but long and heavier: 56kg and 35kW. Lotus has a crank-piston engine, also 56kg, 35kW; it’s more complex and may have service life issues, but it’s compact and relatively light, and it probably won’t pollute. Finally, Mazda is thinking of bringing back its Wankel rotary engine as a range extender. Any of these might win in the marketplace, but I like the Aquarius engine for its combination of light weight, compact size, and simplicity.

This is not to say that Aquarius motors is a good investment. Aquarius automotive went public on the Toronto exchange in December, 2021, AQUA.TA. The company has no profits to date, and the only chance of them making a profit resides in them getting a good licensing deal from an established company. The major car companies have shown no interest so far, though they clearly need something like this. Their plug in hybrids currently use standard-size, 4 stroke engines: 110-150 kW, 100-150 kg, complex, and low efficiency. Consumers have not been impressed. Tesla autos could benefit from this engine, but Musk shows no interest either.

Robert Buxbaum May 5, 2022. I have no stock in Aquarius motors, nor have I received any benefits from them, or any auto company.

A more accurate permeation tester

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There are two ASTM-approved methods for measuring the gas permeability of a material. The equipment is very similar, and REB Research makes equipment for either. In one of these methods (described in detail here) you measure the rate of pressure rise in a small volume.This method is ideal for high permeation rate materials. It’s fast, reliable, and as a bonus, allows you to infer diffusivity and solubility as well, based on the permeation and breakthrough time.

Exploded view of the permeation cell.

For slower permeation materials, I’ve found you are better off with the other method: using a flow of sampling gas (helium typically, though argon can be used as well) and a gas-sampling gas chromatograph. We sell the cells for this, though not the gas chromatograph. For my own work, I use helium as the carrier gas and sampling gas, along with a GC with a 1 cc sampling loop (a coil of stainless steel tube), and an automatic, gas-operated valve, called a sampling valve. I use a VECO ionization detector since it provides the greatest sensitivity differentiating hydrogen from helium.

When doing an experiment, the permeate gas is put into the upper chamber. That’s typically hydrogen for my experiments. The sampling gas (helium in my setup) is made to flow past the lower chamber at a fixed, flow rate, 20 sccm or less. The sampling gas then flows to the sampling loop of the GC, and from there up the hood. Every 20 minutes or so, the sampling valve switches, sending the sampling gas directly out the hood. When the valve switches, the carrier gas (helium) now passes through the sampling loop on its way to the column. This sends the 1 cc of sample directly to the GC column as a single “injection”. The GC column separates the various gases in the sample and determines the components and the concentration of each. From the helium flow rate, and the argon concentration in it, I determine the permeation rate and, from that, the permeability of the material.

As an example, let’s assume that the sample gas flow is 20 sccm, as in the diagram above, and that the GC determines the H2 concentration to be 1 ppm. The permeation rate is thus 20 x 10-6 std cc/minute, or 3.33 x 10-7 std cc/s. The permeability is now calculated from the permeation area (12.56 cm2 for the cells I make), from the material thickness, and from the upstream pressure. Typically, one measures the thickness in cm, and the pressure in cm of Hg so that 1 atm is 76cm Hg. The result is that permeability is determined in a unit called barrer. Continuing the example above, if the upstream hydrogen is 15 psig, that’s 2 atmospheres absolute or or 152 cm Hg. Lets say that the material is a polymer of thickness is 0.3 cm; we thus conclude that the permeability is 0.524 x 10-10 scc/cm/s/cm2/cmHg = 0.524 barrer.

This method is capable of measuring permeabilities lower than the previous method, easily lower than 1 barrer, because the results are not fogged by small air leaks or degassing from the membrane material. Leaks of oxygen, and nitrogen show up on the GC output as peaks that are distinct from the permeate peak, hydrogen or whatever you’re studying as a permeate gas. Another plus of this method is that you can measure the permeability of multiple gas species simultaneously, a useful feature when evaluating gas separation polymers. If this type of approach seems attractive, you can build a cell like this yourself, or buy one from us. Send us an email to reb@rebresearch.com, or give us a call at 248-545-0155.

Robert Buxbaum, April 27, 2022.

Hypochondriacs anonymous: the first step is admitting you don’t have a disease.

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I’m writing a book about reverse psychology; please don’t buy it.

This one’s not by Rappaport

The judge said I had to keep 6 feet away from my ex-wife. So I buried her under the patio.

Robert Buxbaum: the above 3 jokes are from Jack Rappaport — He sometimes sells jokes. April 13, 2022. The ones below are from Gahan Wilson, and the one at right, I don’t know.

These last two are from Gahan Wilson

Ukraine looks like Vietnam or the beginnings of WWI

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The press and our Russian experts claim we’re helping in Ukraine, protecting it from a Russian invasion. I suspect they are wrong, and that our help and protection will prove to be as deadly to all as in the Vietnam war. I’m also uncomfortable with their presentation their framing of Putin as an out of touch autocrat. Putin has popular support, and acts with a strong sense of history, as I see it, just not our version of history. In the Russian version, it was Russia that stopped the Nazis — of Germany and Ukraine. We are not the heroes of WWII in their telling; I doubt we’ll be the heroes of this conflict either.

We have a habit of seeing ourselves as saving heroes as we enter other people’s conflicts. It is how we got into Vietnam, to save the South from the North. It’s also how Europe got into WWI: Russia was saving Serbia, Germany was saving Austria, etc (see cartoon below). We meddle our way, and leave much later than we planned. The result, as in Vietnam and Afghanistan is far more death and destruction than if we’d minded our own business. And US war-dead too. In Vietnam 58,000 US deaths. In Afghanistan 2,400 US dead. and no obvious accomplishment. As Henry Kissinger famously commented: “It’s dangerous to be America’s enemy, but deadly to be America’s friend.”

European aggression in WWII started with the good intention of preventing aggression. It got out of hand, as I fear our good intentions will in Ukraine.

The US troops we’ve sent to Ukraine are not called soldiers. They are “fighting advisors” sent to help the Ukrainians use our weapons. In WWI and Vietnam, fighting advisors are called invaders; it’s how we got drawn into Vietnam. The Russians claimed to send advisors when they entered the Crimea and later the Dundas. We called it an invasion. We can’t be that blind to our own words. Sooner or later, the advisors will start killing each other– something we’ll call an unprovoked attack. Our high tech aid including anti-tank missiles are reported to have killed some 10,000 Russians so far. We don’t seem to think the Russians will mind, or that they’ll give up as the body count mounts. In Vietnam, the more we killed with our high-tech weapons, the more the Vietnamese on both sides called us the villains, and the more Vietnamese joined the fight against us. That’s the future I fear for Ukraine, or worse. The conflict in WWI spiraled quickly beyond the borders of Serbia to include the whole world, and continued through WWII.

Our approach to diplomacy is counterproductive too, in my opinion, and similar to Vietnam too. We call Putin a terrorist, a madman and a narcissist, and then we begin talks with him to end the war. Biden has asked to have Putin removed by assassination.Does he think this will help, or if Putin is removed his successor will be a friend of the US? We demonized Ho Chi Minh, and propped up our favored, corrupt leaders. Minh was popular, as is Putin, and both have valid reasons for opposing us. Putin worries about the expansion of NATO. It’s not an illegitimate worry given Russian history of repeated invasions from the west.

Our desire to remove Russian leadership is a long-standing mistake. It does not lead to peace, or good negotiation, nor even peaceful co-existence.

Russia has been invaded many times. US schools mention Napoleon’s invasion in 1812 and the German’s in 1941, but there are more. They were invaded by the Germans in WWI too, and by the Ukrainian Cossacks in the days of Khmelnytsky, 1646-57. Before that the Polish Lithuanians, 1609-1618, the Swedes, 1701-1709, and in the early days, it was Tartars, Mongols, who invaded and ruled Russia from about 1225 til they joined with the Russian Tzars about 1650. Add to that, our help in the war of the Whites vs the Reds (1917-23) that produced Ukrainian independence — I talk about the relevance here. With a history like that, Russia has every reason to worry about NATO expansion. We should be cognizant of this and stop calling Putin a madman. Let’s accept the Russian version of history, and the sitting ruler of Russia.

Some cite the Budapest memorandum that lead to the removal of “Ukrainian” nuclear weapons –– read it here. It’s short, only 1 page, and deliberately vague. it was signed by Putin’s predecessor, Boris Yeltsin, for the Russian Federation, along with representatives for Ukraine, The US, and The UK. The missiles were not Ukrainian, they were Soviet, and pointed at us. As a result of that agreement, they were dismantled and moved into Russia. There is no sense that this is an invitation for us to protect Ukraine against Russia. The co-signers sort-of agree to protect Ukraine from outsiders (Germany, Turkey,..?), but that’s not clear. We commit ourselves to peace in the region, and can claim that Russia violated the peace first, but there’s no invitation for us to violate it second. Until recently, the UK provided no military aid. China and most of the EU still trades with Russia; if they see a villainy, it’s not enough to stop trade.

Robert McNamara was Secretary of Defense under Kennedy and Johnson, and a key “Whiz Kid” pushing for war in Vietnam. Years later, he decided Vietnam was a mistake. A sad cartoon: the veterans are walking past the grave monument for the 58,000 US dead. I worry we’ll have a similar cartoon after this war.

In my opinion, our best course is to reduce our military aid to providing only basics: bullets, blankets, food… We should reopen discussions with Putin, not demonize him, or try to remove him. Ukraine will likely fight on even without our high-tech weapons. Perhaps they’ll buy from Europe, or from independent dealers. The death rate on both sides will be lower and peace will come quicker without us. Crimea might remain Ukrainian or Russian, but that will not be our decision. We’ve done enough damage for now. It took many years after the end of the Vietnam war for the instigators admit is was a mistake.

Robert Buxbaum April 3, 2022. Much of my thinking about Vietnam comes from Francis Fitzgerald’s wonderful book “Fire in the Lake”. I see it all happening again here. Also worth reading is this 2014 letter by Henry Kissinger about how to negotiate a peace: “Damning Putin is not a foreign policy; it’s an alibi for the lack of one.” It’s a nice insight. He seems to understand diplomacy about as well as anyone.

C-PAPs do not help A-Fib, and seem to make heart health worse.

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In this blog-post, I’d like to report on the first random study of patients with Atrial fabulation, A-Fib, and sleep apnea, comparing the health outcome of those who use a C-PAP, a “Continuous Positive Airway Pressure” device, to the outcome those who do not. The original study was published in May, 2021 (read it here) in the American Journal of Respiratory and Critical Care Medicine. The American Journal, Pulmonary Advisor published a more-popular version here.

As a background, if you are over 65 and overweight, there is a 25% chance or so that your heart rate will begin to surge semi-randomly, and that it will flutter. This is Atrial fabulation, A-Fib. It tends to get worse and tends to lead to heart attacks and strokes. People with A-fib tend to be treated with drugs, aspirin, warfarin, beta blockers, and anti arrhythmics. They also tend to be prescribed a C-PAP because overweight, older folks tend to snore and wake up a lot during the night (several times per hour: apnea).

A C-PAP definitely stops the snoring and the Apnea, and the assumption was that it would help your heart as well, if only by giving you a better night’s sleep. As it turns out, the C-PAP seems to decrease heart health — significantly.

For this study, adult patients between 18 and 75 years old diagnosed with paroxysmal A-Fib (that’s occasional AF) were screened for moderate to severe sleep apnea. Those who agreed to participate were randomly assigned to either a treatment of C-PAP plus usual care (drugs mostly) or just usual care for the next 5 months. Of the 109 who enrolled in the study, 55 got the C-PAP plus usual care, 54 got usual care alone. The outcome was that there were 9 serious, adverse heart events (strokes and heart attacks); 7 were in the C-PAP group.

The CPAP pressure was, on average, 6.8 cm H2O; mean time of use was 4.4±1.9 hours per night. The C-PAPs did their jobs on the apnea too, reducing residual apnea-hypopnea to 2.3±1.9 events per hour for those in the C-PAP group.

There was a non-statistically significant reduction is AF among the C-PAP group. They reduced their time in AF by 0.6 percentage points compared to the control group  (95% CI, -2.55 to 1.30; P =.52). That not a statistically significant difference, and is most likely random.

There was a statistically significant decrease in heart health, though. A total of 7 serious adverse events occurred in the C-PAP group and only 2 in the control group. A total of 9 is a relatively small number of events, but there is a strong statistical difference between 7 and 2.

The authors conclude: “CPAP treatment does not seem to reduce or prevent paroxysmal AF.” They should also have concluded that it reduced heart health with a statistical confidence of ~82%: (1-2(36+10)/512) =82%. See more on this type of statistics.

A possible explanation of why a C-PAP would would make heart health worse is an outcome of the this recent sleep study (link here). It appears that the C-PAP helps restore breathing, but by doing so, it interferes with a mechanism the body uses to deal with A-fib. It seems that, for people with A-Fib, their bodies use breathing stoppages to get their heart back into rhythm. For these people, many of their breathing stoppage are not obstructive, but a bio-pathway to raise the CO2 level in the blood and thus regulate heart rate. The use of a C-PAP prevents this restorative mechanism and this seem to be the reason it is destructive to the heart-health of patients with A-fib. On the other hand, a C-PAP does improve the sleep those patients whose apnea is obstructive. It seems to me that sleep studies should do a better job distinguishing the two causes of apnea. C-PAPs seem counter-indicated for patients with A-fib.

Robert Buxbaum, March 30, 2022. I was diagnosed with apnea and A-Fib some years ago. The sleep doctor prescribed a C-PAP and was adamant that I had to use it to keep my heart healthy. There were no random studies backing him up or contradicting him until now.

A Nuclear-blast resistant paint: Starlite and co.

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About 20 years ago, an itinerate inventor named Maurice Ward demonstrated a super insulating paint that he claimed would protect most anything from intense heat. He called it Starlite, and at first no one believed the claims. Then he demonstrated it on TV, see below, by painting a paper-thin layer on a raw egg. He then blasting the egg with a blow torch for a minute till the outside glowed yellow-red. He then lifted the egg with his hand; it was barely warm! And then, on TV, he broke the shell to show that the insides were totally raw, not only uncooked but completely unchanged, a completely raw egg. The documentary below shows the demonstration and describes what happened next (as of 10 years ago) including an even more impressive series of tests.

Intrigued, but skeptical, researchers at the US White Sands National Laboratory, our nuclear bomb test lab, asked for samples. Ward provided pieces of wood painted as before with a “paper thin” layer of Starlite. They subjected these to burning with an oxyacetylene torch, and to a simulated nuclear bomb blast. The nuclear fireball radiation was simulated by an intense laser at the site. Amazing as it sounds, the paint and the wood beneath emerging barely scorched. The painted wood was not damaged by the laser, nor by an oxyacetylene torch that could burn through 8 inches of steel in seconds.

The famous egg, blow torch experiment.

The inventor wouldn’t say what the paint was made of, or what mechanism allowed it to do this, but clearly it had military and civilian uses. It seems it would have prevented the twin towers from collapsing, or would have greatly extended the time they stayed standing. Similarly, it would protect almost anything from a flame-thrower.

As for the ingredients, Ward said it was non-toxic, and that it contained mostly organic materials, plus borax and some silica or ceramic. According to his daughter, it was “edible”; they’d fed it to dogs and horses without adverse effects.

Starlite coasted wood. The simulated nuclear blast made the char mark at left.

The White sands engineers speculate that the paint worked by combination of ablation and intumescence, controlled swelling. The surface, they surmised, formed a foam of char, pure carbon, that swelled to make tiny chambers. If these chambers are small enough, ≤10 nm or so, the mean free path of gas molecules will be severely reduced, reducing the potential for heat transfer. Even more insulting would be if the foam chambers were about 1 nm. Such chambers will be, essentially air free, and thus very insulating. For a more technical view of how molecule motion affects heat transfer rates, see my essay, here.

Sorry to say we don’t know how big the char chambers are, or if this is how the material works. Ward retained the samples and the formula, and didn’t allow close examination. Clearly, if it works by a char, the char layer is very thin, a few microns at most.

Because Maurice Ward never sold the formula or any of the paint in his lifetime, he made no money on the product. He kept closed muted about it, as he knew that, as soon as he patented, or sold, or let anyone know what was in the paint, there would be copycats, and patent violations, and leaks of any secret formula. Even in the US, many people and companies ignore patent rights, daring you to challenge them in court. And it’s worse in foreign countries where the government actively encourages violation. There are also legal ways around a patent: A copycat inventor looks for ways to get the same behavior from materials that are not covered in the patent. Ward could not get around these issues, so he never patented the formula or sold the rights. He revealed the formula only to some close family members, but that was it till May, 2020, when a US company, Thermashield, LLC, bought Ward’s lab equipment and notes. They now claim to make the original Starlite. Maybe they do. The product doesn’t seem quite as good. I’ve yet to see an item scorched as little as the sample above.

Many companies today are now selling versions of Starlite. The formulas are widely different, but all the paints are intumescent, and all the formulas are based on materials Ward would have had on hand, and on the recollections of the TV people and those at White Sands. I’ve bought one of these copycat products, not Thermashield, and tested it. It’s not half bad: thicker in consistency than the original, or as resistive.

There are home-made products too, with formulas on the internet and on YouTube. They are applied more like a spackle or a clay. Still, these products insulate remarkably well: a lot better than any normal insulator I’d seen.

If you’d like to try this as a science fair project, among the formulas you can try; a mix of glue, baking soda, borax, and sugar, with some water. Some versions use sodium silicate too. The Thermoshield folks say that this isn’t the formula, that there is no PVA glue or baking soda in their product. Still it works.

Robert Buxbaum, March 13, 2022. Despite my complaints about the US patent system, it’s far better than in any other country I’ve explored. In most countries, patents are granted only as an income stream for the government, and inventors are considered villains: folks who withhold the fruits of their brains for unearned money. Horrible.

The claim that Ukrainians are Nazis is also Ukraine’s claim to statehood.

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Recently Putin claimed he was going into Ukraine to fight Nazis. Twitter makes fun of this, but also shows many pictures of these Nazis. Under the hashtag #AzovBattalion, you’ll see many pictures of white boys with swastikas and Ukraine flags (see below). Perhaps these pictures are just Russian propaganda: According to our media there are no Nazis to speak of, and besides, the president of Ukraine is a Jew. Still, the pictures look real, and based on Ukraine history, there is quite a bit reason to think they are not an aberration. Still, to the extent that they represent Ukraine, these individuals are a major basis of Ukraine’s claim for independence. They are also a good reason to leave Ukraine out of NATO, IMHO.

Let’s go back to the late days of the Tartars and the early days of the Cossacks, about 1600. There is a painting, below depicting Cossacks of those days writing a letter to The Sultan (original in the Kharkov museum). They do not seem the most savory of people, but they do seem independent and egalitarian. The letter is not written by a noble, but by a committee of pirates, and not everyone is happy about it.

Zaporozhian Cossacks write a letter to the sultan. These are the people who Putin claims should be loyal to Russia, but they have a long history of behaving otherwise. I like the scribe. A couple of people at left seem unhappy.

From 1250 to the mid 1700s, Southern Ukraine was ruled, to a greater or lesser extent, by the Crimean Tartars, a group of horse-riding Mongols who nominally served the great Khan. Moscow paid dues to them, and in 1571 the Tartar ruler,  Devlet I Giray burnt Moscow to collect his dues. The early Cossacks were Black-sea pirates, and enemies of the Tartars. Around 1600, the Cossacks and Tartars realized they had a lot in common (alcoholism, pederasty…) and formed an alliance. Mainly this was against the Poles and Jews. A famous result of this alliance was the Khmelnytsky Uprising (about 1650). Khmelnytsky was the “Hetman” (Head man?), the elected, temporary ruler for the uprising. He has become a symbol of Ukrainian independence, but he was also a brutal murderer of virtually all the Jews and Catholics. Today, he graces Ukraine’s $5 bill, and sits atop a statue in Kyiv’s central square. This elevation of Khmelnytsky is no small insult to Jews, Catholics, and civilization.

Ukrainian Republic passport, 1919.

 In 1654, via the Pereyaslav Agreement, Khmelnytsky’s Tartar-Cossacks formed an allegiance with the Tsar while retaining autonomy in Ukraine. This autonomy eroded over the years, and ended with Bolshevik rule in the early 20th century. After WWI, Ukrainians briefly tried for independence, forming the Ukraine Peoples Republic and the Ukraine Democratic republic, from 1917 to 1921. The head of the Republic was called hetman, an elected leader but also a throwback to a mass-murderer.

Stalin punished the Cossack remnant before WWIi, and when the Germans invaded in 1939, many of the remaining Ukrainians supported the Nazi invasion, and provided some of the most brutal murders of Jews; the murderers of Baba Year, for example. Putin recalls this collaboration when he calls the Ukrainians Nazis, and I suspect that he’s more right than our press will admit. These #azovbattalion pictures don’t look faked. On the other hand, the autonomy of the Ukrainians and Cossacks, and their attempts at independence provide historical backing for Ukraine’s claim to independence. Putting this another way, the more you accept that Ukraine is full of Nazi sympathizers, the more you should accept them as a distinct society from Russia.

Ukrainians of the Azov Battalion with a statue of Khmelnytsky, or some other murderer.

As an idea of how the war might go, I should mention another group of Tartar-Cossacks. These were Moslems who operated between the Don and Volga Rivers in what is known as Chechnya. Chechnya fought Russia in a long, bloody, unsuccessful struggle, that is only recently ended. Russia may win in Ukraine, but it is not likely to win easily or cheaply if Chechnya is any model.

Robert Buxbaum, Mar. 2, 2022

Jews Believe in Life after Death for Jew and Gentile.

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It is a common misunderstanding that Jews don’t believe in the afterlife. We do, both for good Jews and for good gentiles. While the talmud is clear on this, the Old Testament presentation is vague and poetic. As an example, the Talmud, Pirke Avos 4:16, says, “This world is like a corridor before the World-to-Come. Rectify yourself in the corridor in order to be able to enter the Banquet Hall.” The Talmud and Bible (OT) go to great detail of what to do in the corridor, but there are only poetic allusions about the afterlife banquet. 

One Old-testament allusion is that death is described as going to sleep, or going to sleep with ones ancestors. Sleep here is understood as something that you generally wake up from. The added phrase, “with his ancestors” suggests a certain independence of person, even after death, so that we don’t all merge into a cosmic will. That this sleep is not burial is apparent, for example, with David,  (1 Kings 2:10) , “Then David slept with his ancestors, and was buried in the city of David.” First David’s soul left to sleep with his ancestors, and then he was buried. It’s the same with Solomon, (1 Kings 11:43), “Then Solomon slept with his ancestors and was buried”. This phrase appears also for Jeroboam (1 Kings 14:20), for Reboham (1 Kings 14:31), and for many others including Ahab (1 Kings 15:24). 

Now Ahab was an awful individual, and Jeroboam and Rechovoam weren’t exactly saints. According to Jewish tradition, you can be pretty bad and not lose your share in the world to come. The Talmud, (Sanhedrin 105a), says that, in general, “All Israel has a share in the world to come.” There are a few exceptions, Jews and gentiles who were so bad that they are no longer be part of God’s covenant, but those are rare. The Talmud says that Bilham was such an exceptional individual. He did his best to curse the Jews, and, as in (Gen. 12:3, and Deut 30:7), those who curse you are cursed. From the fact that Bilham lost his share we see that he originally had a share. All righteous gentiles do, according to Jewish tradition. 

Another, Old Testament source that righteous gentiles have a share in the world to come is from the death of Abraham (Gen 25:8-9). “Abraham expired and died, an old man and full of years, and was was gathered to his people, and Isaac and Ishmael, his sons buried him…” Abraham being gathered to his people is understood to mean that he went to join his dead ancestors in heaven — but all of Abraham’s ancestors were gentiles. He’s gathered to the good gentiles in heaven, to Noah and the Noachides. Noah was not a Jew, but he is described as righteous and as walking with God (Gen 6:9). Walking with God is another allusion to being good in this world, and going to heaven afterwards. Apparently righteous gentiles not only go to heaven, but get to gather with Abraham and Noah.

We find that Ishmael was “gathered to his people” (Gen 25:17), as was Isaac (Gen 35:29), Jacob (Gen 49:33), Aaron (Num 20:24), and Moses (Num 27:13). Ishmael was not a Jew, nor particularly righteous, but there he is gathered with Abraham. There is allusion to him being a robber in his early days, “a wild ass among men; his hand shall be against every man” (Gen 16:12). Apparently he repented, and we find him in heaven with Abraham, Isaac, Jacob, Aaron, and Moses. 

That we believe righteous gentiles go to heaven has been a problem for Jewish missionary work: if you can go to heaven without taking on the restrictions of becoming a Jew, why convert? For most non-Jews the right answer is, don’t convert, but live as a righteous gentile.

The details of heaven, and of the afterlife are not well spelled out in the Jewish Bible, the Old Testament, and not in the Talmud. Some Talmudic scholars took the sleep analogy literally to say that one awakens with the body one went down with, and even in the same clothes. One Talmudic rabbi wanted to be dressed nicely for his burial for that reason. Most rabbis do not expect their clothes to resurrect. In Jewish prayer (the Amida, 2nd section) we speak of revival of the dead in terms of plants coming back after a rain. This suggests a different body altogether. No one really knows. 

The Jewish tradition takes heaven as a gathering, and this suggests you can speak to one another after death. There is also a concept of punishment for sin; perhaps the punishment is confronting the people you wronged. We don’t know. We presume that the experience of heaven is more pleasant for those who do good, but the details are hidden. “An eye has not seen, other than the L-rd’s, what He will do for those who hope in Him” (Isaiah 64:3). Bilham says he wants the death of the righteous (Num 23:10), but not the life.

Jewish tradition assumes that one’s marriage bond continues in heaven, by the way. In the Talmud (Taanis 25a), men are described as sitting with their wives, and this provides another bit of evidence that the Jewish belief in heaven goes way back. In the New Testament, in several places we find a story of some rabbis challenging JC to explain what would happen if a woman had seven husbands; (Matthew 22: 24-28, Luke 20: 33-37, Mark 12:18-25). Which husband would she sit with, they ask. JC’s answer is that marriage does not continue after death, and that we would be as angels. The Jewish traction disagrees and says that we’d be more like we are now, with our wives, but the fact that JC and the rabbis are arguing about the marriage bond in heaven indicates that both sides agree there is a heaven.

One reason we imagine our wives will be with us is the idea of becoming one flesh (Gen 2:24), another reason has to do with the fairness of reward. We want to enjoy heaven as ourselves, and not as some angelic version of myself that enjoys playing the harp for a billion years. As for the mechanics of heavenly marriage, one rabbi I knew said that it would be his divine punishment and his wife’s heaven. He imagined his she would want to go shopping all the time, and he’d have to go along*.

Robert Buxbaum, Feb. 8, 2022 *S. Kauffman, of blessed memory.

Wood, the strongest material for some things, like table-tops

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Natural wood has a lower critical strength than most modern materials, and a lower elastic constant, yet it is the strongest material for some applications because it is remarkably light and remarkably cheap on a per-volume or weight. In some important applications, high strength per volume is the important measure, and in virtually every case high strength per dollar is relevant. Consider the table top: it should support a person standing on it, as one might do to change a lightbulb, and it should not weigh too much, or cost too much.

A 250 lb man on a table. The table should not weight too much, nor cost too much, yet it should support the man.

I’ve drawn a 9 foot by 4 foot table at left, with a 250 lb person in the center. Assuming that the thickness of the table is t, the deflection in the center, ∂, is found by the formula ∂ =FL3/4Ewt3. Here, F is the downward force, 250 lbs (a bit higher if we include the weight of the table), L is the length between the supports, 6 feet = 72 inches, E is the elastic constant of the table top, 2,300,000 psi assuming ash wood, w is the width of the table, 48″, and t is the thickness, let’s say 1″.

Using the formula above, we fid that the deflection of this tabletop is 0.211″ for a force of 250 lbs. That’s not bad. The weight of the 9′ table top is 125 lbs, which is not too bad either, and the cost is likely going to be acceptable: ash is a fairly cheap, nice-looking wood.

By comparison, consider using a 1/4″ thick sheet of structural aluminum, alloy 6061. The cost will be much higher and the weight will be the same as for the 1′ thick piece of ash. That’s because the density of aluminum is 2.7 g/cc, more than three times that of ash. Aluminum 6061is four times stiffer than ash, with an elastic constant of 10,000,000 psi, but the resistance to bending is proportional to thickness cubed; and 1/4 cubed is 1/64. We thus find that the 125 lb tabletop of Al alloy will deflect 3.11 inches, about 16 times more than ash, far too much to be acceptable. We could switch to thicker aluminum, 3/8″ for example, but the weight would be 50% higher now, the cost would be yet 50% higher, and the deflection would still be too high, 0.92 inches. Things get even worse with steel since steel is yet-denser, a 1/4″ sheet of steel would deflect about as much as the 3/8″ aluminum, but would weigh about twice as muc. For this application, and many others like it, wood is likely the best choice; its light weight per strength and low cost can’t be beat.

Robert E. Buxbaum, January 11, 2022