Missing Magnitudes

Cell Phone Charger Leakage I had a friend once point out that cell phone chargers use electricity when they're unplugged. This is true, of course, and intuitive to anyone with a basic understanding of electronics. A simple model of electrical circuits predicts that an electrical current will follow the path of least resistance. But what happens if there is no 'path'? Think of this another way: there is always a path from the positive to the negative pole. It's just that sometimes that path is blocked by something difficult to pass through. Even for a normal outlet, there's air between the positive and negative poles. The air is extremely difficult to pass through, but not impossible, so a little power will find its way even through the open air. (This happens at large scales with lightning, where millions of volts and long distances are involved.) But in the case of a cell phone charger, those two poles are brought close together (to keep the plug small and the phon

Is it over yet?

I'm often asked when the pandemic will end. "Is it over already?" "Didn't we see a massive decrease in COVID-19 cases and deaths back in March?" "That means it's over, right?" "Will it be over once enough people get vaccinated?" "If not now, when will it end?" I'd like to give my perspective about each of the questions in turn. I won't say these are 'answers' so much as best guesses: Is it over already? Not yet, sorry. In fact, the pandemic is no less 'over' today than it was at the end of April last year. I know that's hard to hear, but it isn't a bleak as it sounds. If we're able to craft rational policy it won't be bleak, but in order to do so we first have to understand why the pandemic isn't any less 'over' today than it was back in April 2020. Didn't we see a massive decrease in COVID-19 cases and deaths back in March? Yes, just like last year - and for the same r

Beware Lessons from History

This isn't a religious blog, but I figured I'd share an idea using passages from the Bible in honor of Easter. The message of this post isn't religious, so much as it is about one of the unexpected ways we can take wrong lessons from history. For that we're going to use a historical example from ancient scripture. In an earlier post , I talked about one of the most oft-used historical references and how a misunderstanding of history gets the conclusions backward. The popular narrative has us looking back at the most infamous mass-murderer in history; we see him as pushing a ruthless theory based on the hubris of trying to remake humanity into his own vision; we see him coopting an entire nation into this mad vision and wonder how he got so many people to commit atrocities. The real story is exactly backward from that. Hitler didn't push a new vision of humanity, so much as ride the prevailing theory. He didn't convince scientists to try his ideas out, so much as

The illusion of control

 I've avoided posting about the pandemic for awhile now. Partly this is because I made a few predictions that hadn't panned out, as well as others that sometimes looked to be wrong but hadn't panned out yet . I'll start with a mea culpa on the two big predictions that didn't pan out, although I have devoted some space to these before: Mea Culpa The Nordic Experiment: I already wrote about how I got this one wrong, but I want to add some recent data to really put it to rest. This was always an experiment with a small n and a large number of confounding factors (such as, will Swedes act the way their government tells them or will they still practice extra precautions, will other Nordic countries act similar to the Swedes regardless of national policy, will other policies - such as poor cocooning of nursing homes - swamp the policy effects?). Still, the claim was that Sweden's strategy would drive them toward herd immunity earlier, so they would have a large spi

A better addiction

My first year in undergrad I was like many first year college students. I had been spoon-fed information during high school, so I didn't study much when I hit college - not having developed these habits before then. This resulted in a rough first semester. (If you or someone you know is getting ready to enter college next year, probably the most important lesson to learn is to become personally responsible for learning most of the information. That's a good thing, and it's a shame this is a lesson most kids aren't learning until college.) In one of my classes, Intensive Writing, I procrastinated turning in most of the assignments. The professor told us we would have a surprise prompt for the final exam, but gave us some direction before about what kind of prompt it would be. I mulled over what she told us, knowing that if I didn't get a good grade I'd fail the class, based on my performance thus far. When I got to the classroom for the final, the professor confe

Homeostasis versus equilibrium

I want to make a quick distinction between the concepts of homeostasis and equilibrium. It can be easy to think of these two ideas as being the same thing, because both are mechanisms that drive a system that is in a state of change toward a system that is no longer changing. But understanding why they're different can change some low-level lines in our rational operating system code. Bear with me for a second as we cover the basic ground you probably already know. There are subtleties in these definitions we'll pull out if you give me a moment. The payoff should not just be in understanding biological systems better, but also hopefully in understanding larger systems like families, communities, and society as a whole. Let's start with equilibrium. This is the simple idea that things tend to become more uniform over time unless there's something preventing that from happening. This sentence is an example of an initial state that has not reached equilibrium. This s

Start with an Observation

My wife is a science teacher, and when we first started dating she was teaching high-school science to freshmen. On our first date, she described her difficulties teaching the scientific method to her students. By way of demonstration, she asked me, "What are the steps in the Scientific Method?" I said, "Well, you start with an observation, then-" "Exactly! You have to start with an observation. They don't get this concept. They think they start with a hypothesis. 'Maybe you didn't start with an observation, maybe you were just thinking one day and you formed a hypothesis.' But why did you form that hypothesis? If you think back through the process, you did it because you started with an observation. Somewhere down the line you observed something and it caused you to ask questions." I pointed out that this powerful idea isn't just difficult to understand for high-school science kids. It's also difficult for some researchers to