The state of the world is awful

 This is an emotional judgment. I feel things are really bad, and getting worse. The situation is very discouraging.

Most of my blog posts have been from the realm of thinking, and how thinking should often correct our feelings about things.

I have often argued that in many ways, things are better now than they have ever been before in the US, for instance in terms of health care, women's rights, and the availability of knowledge and entertainment to all. They say extreme poverty is overall falling (even though sub-Saharan Africa is an exception). Here's one reference (chosen almost haphazardly) supporting that idea: http://www.fao.org/3/i2280e/i2280e04.pdf.

Those promising facts are background just as climage change is really beginning to show what it has in store for us. I like to think that Covid-19, though a real nuisance, is only a temporary blip. But it is a reminder that if the next pandemic is high-mortality and highly contagious, it is one significant threat to the world order as we know it.

Donald Trump is out of office, but the forces that put him there are still very much alive and well. In the wake of the 2020 election, there were enough Republican elected officials with the backbone to say, "No, sorry, the numbers don't lie, and Trump lost." If he had had another 4 years to work with, it's less clear how things would have developed. And the prospect of him and a successor regaining power for 8 or more years in 2024 is quite real. I have just been reading William Shirer's "Berlin Diary", and am somewhat reassured that Hitler's control of Germany even before the war was much more overt and draconian than anything in the US in the Trump years.

Forces of intolerance and fascism are at large throughout the world.

Prospects in the US of something as simple as a long-overdue $350 billion infrastructure package are still very iffy. The debacle in Afghanistan was due to a non-partisan intelligence failure, and it was going to hurt no matter when the withdrawal happened, but Biden will lose political capital from it. (Could we basically buy the lives of the people we want to protect, by quietly making a certain amount of transitional financial assistance dependent on getting some out and letting the others continue to live in safety?)

The US will continue to see its influence decline. China is a rising power, but so far comparatively benevolent as rising powers go. It seems unlikely this will change the status quo of there being no threats of rich nations fighting full scale wars against each other.

But the emotional truth is that climate change is here for the long run, it is irreversible, and the only question is just how bad it will be. I think we as a species simply lacked the ability to prevent it, which is a dim reflection on our species. Perhaps a conjunction of radical green dictatorships over much of the world could have done something. It would have been highly unlikely, but I can't think of a more realistic scenario.

Aside from climate change, we can imagine all of these things coming and going in the decades and centuries to come. But substituting climate change for assassination, "But other than that, how did you like the play, Mrs. Lincoln?" rings bitterly true.

I can say comforting things on an intellectual level about every aspect of the world situation except climate change. But all the rest feels bad too.

This comes as I have re-established a level of stability in my personal life. I was forced to move this summer, a lurking possibility for a few years, but landed in a very nice one-bedroom apartment in Watlham (10 Middle Street Court, Apartment 4, Waltham, 02451). It has central A/C, an elevator if I need it, and laundry in-unit. It costs a bit more, but I've decided I can afford it. And above all, all of my medical problems seem to be stable for the moment.

Even so, the world feels awful.

World War II Surprises

 

There is a great deal of information on the web. In such matters as "what happened in World War II?" (in contrast to current events) you can hope it is mostly accurate. Studs Terkel wrote a book called "The Good War", about World War II. It qualified for that status because the US achieved complete victory over evil foes. I suppose that's one reason I focus on it rather than later conflicts. Militarily, it was also the last war between more or less symmetrical forces. Since then it's been almost entirely a large, rich nation against insurgents or a much weaker foe.

A few things I think I've learned -- at least strong possibilities to consider.

1. The German invasion of France in 1940 was rapidly successful. But commentators now suggest this was not a predestined outcome due to a fool-proof superior German strategy. Some commentators have said that the Germans got insanely lucky. Hitler, in launching the invasion, did not expect quick victory, but a war that would cost millions of German lives. It was not a planned Blitzkrieg invasion, they say, but rather the success of the invasion in the way it unfolded led the Germans to think such a strategy might work elsewhere too. One French problem that might have been hard to foresee, for instance, was that they had committed their troops in a forward position, but could not bring them back effectively when required because the roads were clogged with civilians fleeing the Germans.

2. The German invasion of the USSR did not come close to defeating them. While the Germans made large territorial gains in 1941, they did so at enormous cost to their own forces. The Soviet military (and the economy to support it) was much larger than the Germans had thought, and that was what ultimately made the difference.

3. There were several assassination attempts against Hitler, and he seemed quite lucky in dodging all of them. There was a speculation that if the Army had succeeded in killing him in the best known of these (the briefcase that got moved), the coup by the professional army would have quickly failed. Nazi forces would very soon have regained control of the country. Goring would be the supreme leader. However, it is possible that Goring would have understood the hopelessness of the German position much sooner than Hitler did, and for instance surrendered a year earlier, saving a great deal of destruction.

4. Now, to Japan. The story I had always heard was that Emperor Hirohito was merely a puppet, and all power lay with the cabinet. The latest is that this was normally true, but when it came time to decide whether to surrender around August 10th, 1945, the cabinet was evenly split, 3 to 3, and in that environment he did cast the deciding vote in favor of surrender. There was not some large peace faction. The Japanese decision was not determined primarily by the atomic bombs. It was far more influenced by the Soviet entry into the war and their potential to quickly invade and occupy Japan's holdings on the Asian mainland and the northern island of Hokkaido. Their defenses were geared to combat a US invasion from the south, not a Soviet invasion from the west.

5. Japan was not a force of pure evil leading up to 1941. Seeking to be a great power, they invaded China and increased their holdings there gradually. The French had previously done that in Indochina, the British in India and Malaysia, the Dutch in Indonesia, and the US in the Philippines. While the Japanese occupation of China was brutal, so was the US occupation of the Philippines. I am still looking for references on how the atrocities compared across these various colonial conquests.

The impetus for war came with the Japanese occupation of Indochina. The French gave permission for this -- the Vichy government, a puppet state of Germany, which was Japan's ally. The US and other western powers didn't demanded that they withdraw, and the US immediately froze all Japanese assets in the US and imposed an oil embargo, cutting off 80% of Japan's oil supply and a great of its other trade. That was a huge disruption to Japan's economy. A US ultimatum demanded Japan's withdrawal from not just Indochina but from all of China. There was some evidence that the US was trying to goad the Japanese into war, so the US could enter the war to help Germany and also deal with Japan. The Japanese attack on Pearl Harbor served that purpose quite nicely.

Pearl Harbor was a strategic miscalculation by a great power. The US economy was roughly five times the size of Japan's in 1941, and when the US responded with all-out war to that attack, their fate was sealed. But none of that really adds up to Japanese evil.

A grave moral question hovers over the extensive bombing of German and Japanese cities by the US and Britain. They knew they were killing large numbers of civilians with many of their attacks, even if a few military targets were included. If we're thinking about "evil", that US policy must be weighed against Japanese atrocities in China, for instance.

Along with information, another lesson of the internet age is that any of it might be false. I welcome corrections to any of what I have written.

Telephones

 A few of my (few) readers are older than I am, and can easily "one-up" me when I speak of "the old days", but I'll set that aside and be happy to hear of your own experiences. To set the stage, I am 66 years old.

Phones already existed in my youth. In my home town of Durham, New Hampshire, you could dial anyone else in town with 4 digits. The exchange was 868 and I believe all the 4-digit numbers began with 2. There were party lines. One ring for one party, and two rings for the other. You could eavesdrop on your neighbor's calls by simply picking up the phone to listen. A private line cost more. I believe I heard of 8-party lines. Even they made sense if you saw the phone as a way to convey very brief messages of a factual and time-sensitive nature, such as when your train would be arriving. They were an add-on to a way of life that was pretty good as it was, without the telephone.

The rule when making a call was to let the phone ring ten times before deciding the person you called was not home. That was a full minute. You can imagine the recipient finishing the paragraph they were reading in the newspaper, folding it and standing, stretching, and then walking down one corridor and another before arriving at the single phone in the house and answering. A different pace of life. Phones very rarely just ring these days without someone picking up, but if you waited a full minute, someone on the other end who was deliberately not answering their phone would think you were... emotional, in some way or other.

My grandfather knew his phone exchange as 'Bigelow 4". On the keypad "BI" mapped to "24" and thus the entire thing to "244". Perhaps that was supposed to be easier to remember. The phones only had 24 letters on them -- Q and Z were missing. Around 1980 a friend told another friend that if she dialed 800-POLISHQ she could hear a Polish joke. She took the bait and when she reached the end, she laughed, getting the joke, sensitive to the fact that there was no Q on the phone. The idea that it was just implicitly between P and R wouldn't have occurred to us.

Most phones were comfortingly heavy things that you leased from AT&T. No need to hold onto the base when dialing -- the weight was enough to keep the phone in place. Phones were all dial phones. In the same mind-set that expected you to wait a minute for someone to answer, the time it took you to dial 999-9099 was of no concern. I believe it was 1970 when I saw my first push-button phone, at a friend's house. I don't know how much thought went into the design, but it does intrigue that I do not believe that keypad design has changed in the 50 years since.

Then there came the message machine. After some number of rings (I don't think it was 10 -- more like 5, perhaps?) the machine came on with a prerecorded greeting and you could leave your message. First they were a novelty, then they were common, and there came a point where someone was strange if they didn't have one. When I was in France on a brief visit and heard a message machine come on, I briefly thought, "Wow, they work in French too!" before realizing how silly that was.

And then there is the Business Phone. I have few memories of the early days, probably because I didn't have much occasion to call businesses when I was young. As late as 1972, at a summer job right out of high school, I was tasked with calling ten textbook publishers to ask for what books they had in some specific field. A long-distance call was a Big Deal. And I was supposed to make ten of them in a row! Even though it wasn't my family's money, I was very sensitive to spending somebody's $2.00 a minute, no small sum in 1972 dollars. Perhaps my long-term anxiety was a bit less after I had made those ten calls.

Businesses developed phones with rows of transparent cubical buttons on the bottom to deal with multiple lines. The concept arose of putting someone on hold, of seeing which of several lines might be free. The job of "secretary" was still going strong, and that was part of the job. The human secretary took the messages, often on small pink pads of paper.

This and message machines jointly created "telephone tag", where parties would call each other back and forth and leave messages, neither making it a high priority to actually answer calls.

A friend had worked as a secretary at the Pentagon, and she noted that when officers called each other by way of their secretaries, the lower-ranking officer was obliged to come on the phone first. If the two were of the same rank, the one who achieved that rank first was higher in the pecking order, and tables were available to the secretaries to look this information up.

I don't know when it began... I would have guessed 1984 or so, as it impacted my life? The dreaded development was the business where an automated system answered your call, and after describing several options you were to press one key on your keypad. Businesses are always trying to save money, and it's easy to see how this could save them some secretarial time. If all you did want to know was the store hours, the street address, or the fax number, an automated system could give you that information. It might take you ten times as long as if you could simply ask a human who answered for that information, but that time was your time, not the time of an employee of the company. Soon there came to be one button press leading to a litany of further choices. Sometimes, after all that, you were actually directed to a human. However, you might be "waiting for the next available agent". In the old days, you had no idea how long you might be waiting. In more recent years, the company will often give you some estimate. In either case, this provided a very good justification for "speaker phone" mode.

I remember being annoyed when I first heard "please listen carefully as our menu options have changed". Surely they would give me the date on which they last changed so I could tell if I had to listen or not? No way. It just became a piece of boilerplate.

There came a time when after making a choice the phone might emit a couple tones at a volume to wake the dead, part of their internal signaling system where one electronic agent conveyed information to another, at the expense of your eardrums.

I have had the experience a few times recently, after some elaborate maze of choices and holds, a voice finally came on the line, and, it was -- a real human! It was almost startling.

Of course there was another way the companies came to be saving money besides handling as many calls with automated messages as possible. The expected delays were sufficiently burdensome that you might often just not make your call, deciding you could live without that information.

To my awareness, Google was the first company that simply dispensed with customer service entirely, at least for ordinary users. It surely saved Google a LOT of money. The theory was that the information was available online somewhere, or you could find a forum and ask your question and perhaps find an answer. I think companies also stopped trying to write user-friendly documentation. Some enterprising geeks would have written their own versions, and quite likely at least one of them was better than anything the company would write (and they could avoid time-consuming reviews for accuracy and completeness).

The one place where the trend seems to be slower than elsewhere is the health care sector. I find I can often get a human being pretty quickly at the doctor's or dentist's office. I speculate this is because those businesses are not under the same cut-throat competition as others.

But I do really long for the days when after you bought a product from XYZ Corporation, if you had a problem you could dial a number, and immediately talk with a knowledgeable person who could solve your problem!

Review of the movie 'Ponette'

 

Just last night I saw "Ponette", a 1996 French movie. It had been on my list for some time, but it just made its way into Netflix's DVD collection. It is about a 4-year-old girl (Ponette) whose mother dies in a car crash, and her efforts to come to terms with the loss, including being unclear on whether her mother might come back, or at least speak to her. Emotional intelligence suggests she could use some patient listening and affection from the adults around her, but they instead are annoyed with her for not accepting her mother's death.

Most of the characters are children around her age. Ponette (and the other children too) are doing a terrific job acting -- not just saying lines. And it is not just a few lines here and there. It is a full movie's worth. That acting is extraordinary in it own right. Ponette is not helped by having an atheist father (who can only visit briefly now and then) but an aunt and other adults who give different versions of Catholic theology, garbled by the other children's questionable interpretations as well. My enthusiasm was tempered a bit when I had to remind myself that it was the director who wrote the lines the children say. It is a tribute to their acting ability that I was so easily taken in to think that was what they were saying and thinking in the moment. The director has picked a movie's worth of entirely plausible lines.

This aspect reminds me a bit of <this stunning piece>  where a mother has her small daughter say things the daughter has said to her over time. There is no pretense that she is saying them in the moment, but her voice in restating them makes them more compelling.

Is her mother to be resurrected now, or later? Jesus was resurrected, but that is different. God is listening to our prayers and answers them (Ponette's skepticism on this point arises earlier in life than most people's). Her mother is at the right hand of God. Ponette would like to die so she can join her mother in heaven. One boy cruelly tells her that her mother's death is her fault, and only very bad children make their mothers die. Her mother comes to her in a dream, but dreams are not real. One girl says she herself is a child of God but to get to be one you have to pass a series of tests. You could imagine a Unitarian-Universalist mini-course on the theology Ponette struggles with (just kidding).

The one problem with the movie (and on searching I found that Roger Ebert agreed with me) is that Ponette's mother makes an appearance in the flesh at the very end. I initially thought this might be some aunt who was taking the role of her mother in an effort to help her, but it becomes clear that it is magical realism instead. Ponette has been dealing with a confusing and harsh reality up to that point, and the movie betrays us (and Ponette) by giving it up. But the movie stands on its own without that ending.

Evidence-Based Abortion

 

This post is inspired by "The Last Children of Down Syndrome", by Sarah Zhang, in the December 2020 issue of "The Atlantic". The starting point of the article is how few children with Down syndrome are being born in Denmark, a country which offers to all women free genetic testing. Abortion is not just legal, but socially accepted and even expected in cases where Down syndrome is detected. The article raises many issues, but my main reaction is that it is examining a subject that is "tame" in many respects, and more interesting questions arise if we let the wild beasts loose and discuss those issues.

Zhang tells us that when people do have a Down Syndrome child, they typically love him or her and feel glad they did not abort him or her. By extension, those who are considering an abortion also realize they would likely feel the same way if they let the pregnancy continue. Going beyond the premise of the article, this is surely the case for the far more common situation where a woman aborts because she does not want any child at that time. Some women regret that choice, but a great many do not. For those women, a fetus is not a child with the rights of a child, but just a potential child.

As an aside, I join most people in feeling that a woman has an inalienable right to bring to term any pregnancy she has, regardless of what she knows about it.

One of the key elements is information. In the old days, pregnant women knew only that they were going to bear a child (or perhaps two) and knew nothing about them. With prenatal screening, there is some information, and an ability to choose. When is there too much information?

I read an intriguing short story not long ago about a society where they could determine the exact genetic sequence that a woman or man would contribute to a baby if they were to have intercourse right then. This doesn't require much fiction for women, where the identity of the egg and its genetic make-up are in fact determined, and the only scientific problem is how to detect it. It is less plausible for men, but you could imagine technology that would somehow identify the one sperm that would do the fertilizing. The story continues to include an app on each person's phone that would automatically be loaded with that genetic sequence, and an app that can combine them so it knows the genome of the baby that would result if the two of them had sex. Technology had also advanced to the point where they could "age-progress" this genetic sequence forward and get a good indication of what the child would look like, its IQ, its likes and dislikes, and its mannerisms. You could look at a little video of the child you could make with this person you're with. Faced with shrinking populations, governments might subsidize the program!

I expect this is a world that would drive people crazy with anxiety and grief. There is no physical embryo whose rights a person might want to protect, but there is an "informational baby". If you're sitting next to someone at a concert, or waiting in some line, or in your aerobics class, the two of you looking at your phones can see a potential baby. But if you don't have intercourse with that person, such a baby will never exist. If a woman turns to the man on the other side of her, the profile of a different baby will appear. The failure to have intercourse with each of these other people is killing a baby whose properties you can identify. TMI today stands "too much information" and is used today in a lighthearted way, but in this imaginary but possible world it would apply with full force.

One aspect that is absent from most debates about abortion is what the economists would dryly call "opportunity cost". If you live in a world where pregnancies are planned, terminating one baby likely results in the creation of another one. On its more ominous side, carrying the one baby to term precludes life of another baby, even if we in fact don't know anything about its properties.

As for knowing you will love any baby you get, consider this case. A woman who would never have an abortion gets pregnant by a brutal rape. Chances are that the resulting baby will be as delightful and charming as any other baby. Beholding her delightful 3-year-old, can the woman say she is glad she was raped, since otherwise she wouldn't have the baby? She might say that, but surely no one wants to work backwards and offer it as an excuse for rape. Imagine a rapist in our science fiction world showing his victim the baby that would be born if he follows through with his rape, and telling the woman that unless he rapes her she is denying that baby a chance at life. We are in the territory of moral nightmare.

As a result of all those considerations, I feel like a woman should choose whether or not to continue a pregnancy, armed with whatever information she has, without any moral qualms. Sarah Zhang is shocked by a parent of a Down syndrome baby saying, "we would have asked for abortion if we knew". She shouldn't be shocked. A mother after a bitter divorce can say, "I wish I hadn't married him" without betraying her children by that marriage. Telling your child, "I wish you had never been born!" is typically a very bad thing, said in the heat of anger about one's current feelings. But if in a calm and loving moment, as a result of questioning and honest conversation, you admit to your child that they were the result of an unplanned pregnancy that upset you a great deal, that is just telling the truth.

An issue that the article touches on is that of removing heritable genes from the gene pool. Down syndrome is not caused by the allele of a particular gene, and in fact those with Down syndrome very rarely have children themselves in any case. If the genes for Tay-Sachs or cystic fibrosis plummet in the population, few people will mourn. There are other genes that we will identify that tend to make a person dumber, less attractive, less athletic, less outgoing... and we will argue about those. But, to get whimsical for a moment, suppose there were a detectable gene that strongly predisposes a person to become a Republican. That would invite a field day of comment and argument.

A far more consequential form of screening is the abortion of girl fetuses, notably in India. Here the undesirable trait to be eliminated is in fact a necessary trait of one of the two parents. How do Indian women feel about having their girl babies aborted? Perhaps the same culture that allows such a practice enforces silence on women about such issues. Perhaps there are such articles that I do not know about. Or perhaps the women share the same set of beliefs. I have heard of Jewish mothers who are elated to find they have given birth to a son, since the life of a woman is so hard in Judaism (as they see it).

My conclusion that people should choose whether to abort fetuses given what they know does not address this case in India. My view does not allow for moral outrage at the termination of any particular girl fetus. If a family from any culture has three girls and chooses to abort female fetuses until they get a son, my principles don't object to that, and similarly a family of three boys can abort male fetuses until they get a daughter.

To the extent I deplore society-wide selective girl abortion (and I do) it has to be on other grounds. A topic for another day.

Lots of photons

If a person is inclined to think about the very small or the very large, huge numbers arise. One billion trillion stars in the observable universe. (10 to the 21st power). As for atoms in the human body? 10 to the 27th power. But exponents in the 20s are just symbols for us -- we have no intuitive sense of them.

One way of making large numbers real has had me going "wow!" lately. Photons. Lots of photons. Consider a fixed cubic millimeter of space, say in your front yard. A millimeter is about one 25th of an inch. A cubic millimeter is the size of a sesame seed, roughly? A sunflower seed is too big. If you stand three feet away and look through it, you see something on the other side, and let's assume that it's three feet away, and it might be something different from what you see through the cubic millimeter right next to it. (Let's say you've got one eye closed to keep it simpler). It also might change rapidly in brightness or color. Think of a strong wind blowing the leaves on a bush. The light reaches your eye from each point on that bush as it changes. But back to a single point, this happens because a steady stream of photons is traveling from that point on the bush through your chosen cubic millimeter of space to your eye. If you move your eye one millimeter to the left, there is a different steady stream of photons going through that central millimeter at a very slightly different angle. This continues as you move around in a circle, one millimeter at a time. It continues as you lower your head a bit or stand on tiptoes. And of course it continues if you could move your eye further up or down to each square millimeter on the surface of a 6-foot sphere. From each of those locations, you receive a different steady stream of photons from the point directly opposite you that travels through the original cubic millimeter in the middle. My quick calculation is that there are 10 million separate square millimeters on your 6-foot sphere, but you probably get a more intuitive understanding of the size if you think of it one millimeter at a time than 10 million (1 to the 7th power).

There's also a steady stream at every different wavelength of light in the point you see. Say there are 20 relevant wavelengths/colors of visible light your eye can distinguish.

Doesn't it seem like it would get awfully crowded in that cubic millimeter, with all those photons whizzing through? But they hardly ever bump into each other. Each travels in a straight line, unaffected by all the others.

I chose a millimeter to keep it at a size we can understand, though in fact light likely travels reliably in a certain direction at angles much more precise than that. If the Hubble Telescope turns its very sensitive eye in a particular direction, it counts on a stream of photons traveling through light years at exactly the right angle to fill in an accurate image, distinguishing tiny angles, while an equally accurate image would be formed pointing the telescope in each direction, or positioning the telescope at a slightly different location and then going through all the directions. That's a lot of photons! Though the Hubble takes a long exposure because it is not such a steady stream at such tiny gradations and it's adding them up.

Different things make different people go, "Wow!" But that's my candidate for the day. I wonder if anyone who's gone further than me in physics (which was one high school course) could tell me if I've got this right or not.

A Lighter Topic -- Quabbin, Wachusett, and Ware

 

After discussing how hard it is to combat racism and how bleak the political outlook is, I figured it's time for a lighter topic.

A few decades ago I learned a bit about the system that provides water to Boston and surrounding communities. Here's the gist: Quabbin is a big reservoir far away, and Wachusett is a smaller reservoir half way to Boston, and the Ware River is halfway between the reservoirs. What I learned then is that there is a tunnel from the Ware River to the Quabbin, and depending on conditions, water might flow through the tunnel east or it might flow west. When there's lots of water flowing (like, lots of rain), the excess Ware River water goes west to help fill the Quabbin. When there's less water, the Ware River is undisturbed, and water from Quabbin flows east past the Ware River and into the Wachusett reservoir. I thought it was very clever.

The web did not exist when I first heard of this a few decades ago, but now it is so easy to get information! I checked today to see if it's true, and apparently it is. What's more, it's still true (you can imagine water usage patterns changing in the interim). The system is a little bit, kind of, like breath feeding bagpipes. The bag holds enough air you don't need to breathe into it all the time.

The Ware River is of course long, and the key point on it for this purpose is the Ware River Diversion.

Today the new thing I learned is that sometimes (when Ware River water is about to be shut off, I think), it is used to fill a natural siphon that lifts the Quabbin water high enough so that near the Wachusett it is used to generate electricity. Detail: the turbines can only handle so much water, though, so if there's more flowing east, then some of it is diverted straight to the Wachusett.

Reasoning about it, it looks like while the Ware River water could be used to generate electricity when there is plenty of water, it is more valuable as water to be used later than a source of power, so the water flows west and the turbines sit unused.

Figure 3 in <this paper> is the one I can make most sense of. First, note that the Ware River is way up in the air compared to the two reservoirs. Since when is a river higher than the land on both sides of it? In this case, I guess it is.

The western pipe has to be deep enough that it can feed water eastward even when water levels are very low. But that is so deep that you can't make use of the water's drop in elevation to generate power when water levels are higher. The siphon lets them take that water heading east and then lift it up high enough so they can get power out of it when it goes downhill again, near the Wachusett.

Or maybe the pipes near the Ware River aren't all that deep, and the system relies on a siphon to just get the water out of the Quabbin even when water levels are low? I can't tell.

I didn't even try looking at the subject of the paper. The idea is that humans have to make decisions about how to set the various valves, and optimal operation requires the right decisions. The paper describes dynamic prediction about this. Lots of scary equations there. But I thought the basic plan was interesting enough to write about!