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In psychology, there is a phenomenon called “anchoring” in which an initial piece of information acts like an anchor for and affects that context in the future. Essentially, it is the same thing a the concept of a first impression. It is problematic because it sets up what may be unrealistic, or even false, expectations. For example, if the first time you met someone was while they were having a really bad day, you might think of them as being a grouchy person from that point on and avoid them, even if they are actually very nice and you would have liked them otherwise.

Beginner’s luck is the phenomenon in which someone who tries their hand at something for the first time gets lucky and does well. The classic example is of someone playing a game like poker or other game of chance and happening to win a few times.

When these two phenomena get combined, it can lead to extreme frustration.

An example, I have experienced multiple times (which is actually what lead me to notice this effect in the first place), is with video-games. There have been numerous games which I played and did well in at the start, but then ended up having a lot of difficulty with (and it wasn’t due to levels increasing in difficulty). It may have been easy the first time, but I kept doing the same things over and over again without success. Sure, I may have been getting better and better with each try, due to practice, but it wasn’t as easy as it was the first time where I just sailed right through. The only conclusion is that I just happened to get lucky that first time, which then set my mind up to think this game is easy, which in turn caused a lot of grief later when I had trouble and could progress as easily and fast as I was expecting.

What’s more is that the opposite holds true as well, but is usually less noticeable. If one experience beginner’s bad luck the first time with something, then you get the notion that it is hard or unpleasant or some other negative experience, which often causes the person to abandon it altogether, so like with the grouchy person example, they will not even know what it was actually like and miss out on an opportunity. However, it can also lead to frustration in the same way as with beginner’s luck. For example, if you tried something that was very difficult the first time and you enjoyed the challenge, but subsequent exposure turned out to be too easy and boring, you may get frustrated with it and feel betrayed.

As the old saying goes, first impressions are important. The reason is due to anchoring.

There exist some ice-trays that instead of having slots for 10-12 large standard-sized ice-cubes, has slots for dozens or even over a hundred tiny ice-cubes. It might seem absurd, but they’re actually a good idea. Having a lot of small ice-cubes means the ice has a lot more surface-area, so more ice touches the liquid, and thus chills it faster. This is why some drinks use crushed-ice. Of course, “There is No Free Lunch™”, and the cost for this faster cooling is that the ice melts faster.

tl;dr

Most laymen tend to completely misunderstand “Schrödinger’s Cat”, believing it to mean the opposite of what he intended. 🤦

The most common misinterpretation of Schrödinger’s Cat is that until you look in the box to see whether the cat is alive or not, it is both alive and dead, and sometimes also that things don’t exist unless observed. Obviously that’s absurd, and that absurdity is the whole point.

Erwin Schrödinger was a physicist at a turning point, just at the cusp of quantum physics. At the time, the Copenhagen interpretation was making waves (pun intended) in the physics community with various new ideas that were hard to come to terms with for physicists that were used to classical Newtonian physics.

Schrödinger thought the concept of quantum superposition, in which a particle/photon can exist in multiple states at the same time until it is observed or measured, was absurd. (In this context, observed and measured simply means to interact with it, such as to bounce light off of it to see it, or to use magnetic fields to measure it.) To demonstrate the absurdity, he contrived his cat thought-experiment.

In the thought-experiment, you place a piece of radioactive material in a box along with a detector, a vial of poison, and a cat. The radioactive material emits particles randomly, so at any given moment, there is a chance of it emitting a particle or not. If it does emit a particle, the detector will trigger a hammer to break the vial, which in turn, will kill the cat.

His argument is that because the radioactive material may or may not have emitted a particle, the cat may or may not be alive; it is in a superposition of states, which you cannot know until you open the box to look.

Obviously the cat is either alive or dead regardless of whether you look. There are countless examples of events happening with or without being observed, even events that don’t include any sort of life-form.

This was exactly Schrödinger’s point. He was using reductio-ad-absurdum to demonstrate that because the end-result is absurd, its starting point (the presupposition of superposition) must also be incorrect. Einstein agreed (in fact, Einstein also thought quantum entanglement was crazy and made no sense as well; quantum physics was quite the thorn in his side).

tl;dr:

In short, Schrödinger’s cat is not saying that the cat is alive and dead until it’s looked at, it’s saying that quantum superposition doesn’t make sense because it’s absurd for the cat to be alive and dead at the same time.

Next time the concept can come up, you can say the correct interpretation and impress your friends (or annoy them if they’re ignorant and lame).

If you go to a grocery or bulk-foods store and get several similar items that have the same price such as different flavors of the same brand of chips, different styles of the same brand of canned-soup, etc. you may have wondered why the cashier has to scan each one separately instead of just scanning one and multiplying by the number, or for bulk-foods, keying in one item and weighing them all together. There are actually a couple of good reasons for this.

• Inventory
  By scanning each item with a unique barcode separately, they can keep track of inventory without having to manually check the shelves. This makes it easier for them, which means less work, which means lower prices (or at least in theory). If they scan one UPC for multiple different items, then their inventory will be incorrect and they will order too much of something they already have and not enough of something they need.
• Accuracy
  Just because items are similar doesn’t mean they’re identical. It’s entirely possible for one flavor of soda to be more expensive than the others or one kind of socks to be on sale, and so on. If they scan one item multiple times for all of them together, then they could end up over- or under-charging you.

It’s necessary for cashiers to scan each item separately, but it’s only necessary for each unique item; if you get more than one of the same item (e.g., same item-code/UPC), then they can scan one multiple times.

A new computer mouse will usually function just fine, but over time, it will usually start having some problems with the buttons. One common problem is for it to keep releasing prematurely as if you let go of the button even though you didn’t, you may have simply decreased the pressure on it. Another problem is for clicks to not register at all. Assuming there is no physical damage (e.g., dropping the mouse on a hard surface), both of these problems are usually caused by the same thing, a layer of patina growing on the metal contacts inside the switch under the button. This is normal; oxides regularly accumulate on metals which make them less conductive. This is usually fixed by simply cleaning the metal. Unfortunately, the micro-switches used in computer-mice are too small and to inaccessible to open and clean. Fortunately there’s a pretty easy solution with just a bit of vinegar:

0. Disconnected the mouse and/or remove the batteries
1. Open the mouse (there are typically only a couple of screws)
2. Locate the micro-switches; they’ll usually look like the Omron switches below
3. Dip a cotton-swab (Q-tip) into white-vinegar
4. Dab the switch several times to wet it
5. Press the switch a bunch of times to allow the vinegar to soak in and coat the metal
6. (You can leave a blob of vinegar on the switch for a couple of minutes)
7. Use a paper towel to soak up excess vinegar and dry button
8. Repeat with some water (distilled if possible) to remove the vinegar
9. You can dry it more thoroughly by blowing hard on it to eject any remaining liquid
10. Close it

The patina should be removed and the metal contacts should be properly conductive and last a few more years before giving problems again.

Important: Make sure to not leave the vinegar or water on for too long. Otherwise, they will corrode the metal and make the copper grow a green patina which, while pretty, makes things worse, requiring you to open the switch and try to clean it directly which has a good chance of totally ruining the switch and requiring you to completely replace the whole switch (which depending on the mouse—like some very expensive gaming mice—might be worth the effort of putting in a fresh new switch).

This past summer, I updated the MotD of my Orange Pi to include the current weather whenever I log in. It worked great… until recently. For the past week or so, I noticed it wasn’t showing the weather when I logged in.

It turned out to be a simple error and easy fix. The command works by downloading the current weather from the Internet, then using SED to scrape the current temperature and status from the resulting page using a regex.

The problem is that it does not account for negative temperatures, which is what the temperatures are now in the winter (at least in Celsius), so when the temperature is below zero, it does not find the information because the pattern does not match. The fix is simply adding an optional negative sign (-\?) to the regex (optional in the regex sense; it’s required to make this work correctly):

root:/> more /etc/update-motd.d/32-weather
#!/bin/bash
curl -s "http://rss.accuweather.com/rss/liveweather_rss.asp?metric=1&locCode=NAM|CA|ON|LONDON|" |\
sed -n '/Currently:/ s/.*: \(.*\): \(-\?[0-9]*\)\([CF]\).*/\2°\3, \1/p'

At most intersections, you can usually find a pair of “beg-buttons” for pedestrians to push to tell the traffic-control system that they are there and want to cross. There are usually separate buttons for each direction (one for crossing north-south and another for crossing east-west). This results in up to eight buttons at each intersection. However, this is wasteful over-engineering. In fact, with proper software design, only a single button is ever necessary at each corner of a standard 4-way intersection. Can you figure out the logic to prove this?

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That explanation that psychologists came up with back in the 1950’s is incredibly specious because it’s not the same on the return trip because everything is backwards. The roads are different (and might require a different route due to one-way streets), and all of the sights are different because you are seeing everything from the other side. It is a completely different experience. Also, unless this is the first time you’ve been to that location, then the novel-there-familiar-back explanation makes no sense.

A better explanation is that the trip there is likely under a deadline while the return trip is more free. The pressure of trying to stick to a schedule puts added stress on the brain and makes time feel lengthened like most stressful or unpleasant situations have a tendency to do. The freedom of making it back at your own pace (melting ice-cream notwithstanding), relieves you of that burden and so the trip feels shorter.