When Given Cold Weather…

A flash-frozen soap bubble.

When given lemons, make lemonade. 

When given subzero temperatures, freeze soap bubbles. 

This is one of those things that I have wanted to do for some years.  Living in a place where the temperatures drop to levels well below those in your freezer that solidify water and can preserve slabs of reindeer meat, each year I enjoy a few days of dangerously cold weather.   One can throw a pot of hot water up in the air and it turns into a spectacular cloud of steam and snow; no liquid lands on the ground!  It is also possible to blow soap bubbles that freeze into gossamer ice globes.  They are delicate and beautiful, and I have long wanted to photograph them.

Each year when the outdoor temperatures drop sufficiently, I have tried to do this.  Invariably, there is too much wind—any wind is too much—and the bubbles wander away.  The ones I can catch, usually burst before I can take their picture.

This year however, I had a new strategy.  We recently installed windows on our outdoor screen porch.  The temperature remains cold, but the wind is completely blocked.  I can now make soap bubbles and they won’t get away!

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The Wall of Books

This is adapted from a tribute that my father made at the memorial of his father, Theodore Olson, after whom we are both named, who died in 2002 at the age of 97.  I post it here for the online access of posterity, and to provide a portrayal of the scientific mindset of a family patriarch that influenced not only his students, but his entire family and several generations beyond.  Here is my father’s rendition of our family history.


The start of this story goes back almost 150 years. In about 1860 in Norway, Hans Opjörden left home and went to Oslo. Hans had the misfortune to be the second son in his family, and that meant that his older brother would inherit the family farm. Hans left home and headed off to Oslo, where he went to work in a shipyard building boats. After a while he decided he really wanted to sail on the boats instead of just building them. At this time Norway was a province of Sweden.  Shrewdly, Hans changed his name from Opjörden to Olson (with a Swedish spelling) and got Swedish sailing papers.

He went on several voyages and along the way befriended a shipmate named Peter Magnus Peterson.  We can imagine a conversation between them based on what subsequently happened.  Hans confided that he’d really wanted to be a farmer but had no prospects of getting land—and that being a sailor was not his “dream job”, but was good paying employment. 

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Swedish Candelabras – Finis

It is considered good practice to finish up the old projects before embarking on new ones, but that doesn’t seem to be my way.  The new one gets started and the old one languishes in its nearly complete state, sometimes for years, until I grant amnesty, allowing it to fade into memory.

I had reached the point in the Swedish candelabra project where the challenges of woodworking had been solved, a working prototype had been made, a dozen pieces had been crafted, and all that was left were the trivial details of wiring the electric LED candles.

It turned out that, while not technically challenging, it was incredibly tedious, threading wires, stripping insulation, soldering the bulb contacts, splicing connections and gluing the simulated plastic candlesticks in place.  The first one I assembled took hours.

With eleven more to go, I found lots of excuses to not do them.  Eventually however, when the summer heat advisories provided reason to retreat to the cool workroom in my home, I would complete one, or maybe two, each day.  Eventually I reached the last one, by which time I was proficient– only an hour of assembly!

I can now declare this project complete, and I look forward to displaying the candelabras in our windows when the season shifts once again to long cold nights.  I hope they are seen by the passing neighbors as signs of hope, warmth, welcome, and good cheer, just like the ones we enjoyed in Sweden.

The ancestral home of my great-great-grandfather Sven Johan Lundberg in Mulseryd, Sweden, during a light snowfall last December. If you look closely you will find that each window hosts a welcoming candelabra.

The 15-minute rule, and other covid recommendations

Keeping an eye on my watch while conversing.

Since writing the previous blog entry (“What is my risk?”) I have encountered additional information to refine the risk calculation I outlined.  I found a reference that provides a better value for the relative intensity of aerosol generation between the activities of talking and passive breathing: approximately 10X (compared to my placeholder value of 2).  When this weighting is applied to the social interaction duration histogram, the critical exposure is reduced from four person-intensity-hours to three.  

This does not seem like a large impact on critical exposure but the intensity level associated with talking now requires that all of those short interactions become shorter.  If the critical exposure is 3 hours at level 1 (silent breathing in the same room), and talking is 10 times more intense, then an exposure of 0.3 hours (18 minutes) in conversation with an infectious person will deliver the critical dose of virus-laden aerosols.  This suggests a limit of 15 minutes in any interaction with a stranger: the 15-minute rule.

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What is my risk?

Taking a calculated risk at a favorite restaurant’s outdoor patio

Ever since the covid19 stay-at-home orders were relaxed for my state, I have been struggling to find some rules to guide me as we try to safely host small gatherings with qualified friends (today’s rules: outdoors, safe-distancing, maximum of two guests–who have also been in semi-quarantine).

I’d like to know “what is my risk?” after encountering N people in a day and spending a certain amount of time with each.  In particular, if I interact with store clerks for a few minutes each, walk or bicycle past maybe a hundred people, or sit in a (sparse) movie theater with a few dozen others for two hours, what risks am I taking?  I want to put it in relative terms with the risk I willingly accept when I drive a few miles for an everyday errand.

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Swedish Candelabras

A modest Swedish house in Skalo, Poldi’s ancestral home. Nearly all the houses are in this traditional red color with white trim.
A close up shows the candelabras in the windows, a wintertime custom here.

While in Sweden over the Christmas season, we noticed the popularity of candelabras placed in the windows of people’s homes.  In these northern latitudes where the darkness of the winter night dominates the few hours of daylight, the distinctive chevron of lights provided a cheery greeting from the windows of the traditional-styled Swedish houses.  

I thought it would be a nice accent to our own home with its not-so-traditional windows cut into a mansard roof.  Surely Ikea would have such an item, with some suitable unpronounceable name, but I was disappointed.  Perhaps I needed to shop the Ikea stores in Sweden rather than our Americanized versions of them.

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