The Sounds of Summer

Ah, the sounds of summer, a summer now almost free of Covid-19.

The sweet song of the ice cream truck, the cooing of doves, the reverberating bounce of a basketball, the shrieks of kids doing whatever kids do.

The night also has sounds, some good and some annoying.  One of the worst is the hum, buzz, click clacks, and muffled sobs of air-conditioning.  The just-as-you're-fallling asleep blare of the air conditioner cycling. 

 Turning the volume of your television so high that folks a mile away can hear it, so that you can hear it over the air conditioner.

Why are air conditioners noisy? What are all of those dissonant sounds? 

The basis of air-conditioning seems simple: a compressed gas released through a small hole becomes extremely cold.  The heat inside shifts eagerly to the cold air and is then whisked away. Something like that. 

As suggested, an air conditioner has a compressor.  It's there to compress a refrigerant, which means a chemical that destroys ozone, or it used to.  Safer refrigerants are now used.

Once the refrigerant is cold, it is circulated through a series of tubes, which unwound, would be a zillion miles long.  The circulating cold in the tubes takes the heat of the room away.  A fan behind the tubes blowing into the room, helps the process along.  

When the tubes warm up the refrigerant travels to another region of tubes.  There the refrigerant condenses.  This place is called, reasonably, the condenser. It's connected to the cold tubes but on the outside of the window. As you may recall, condensation releases heat.  Another fan helps blow the warm air away, The refrigerant travels back through the compressor and the whole cycle begins again. 

So, that helps explain the noises. The compressor is an electrical device, probably not well shielded for sound, and designed to work non-stop for months or years. The refrigerant is gurgling through the tubes, creating a lessor drumbeat of noise.The fans may be creaky or unbalanced.  The axles that the fans spin on may be a bit warped or twisted.

The cover of the air conditioner is made out of relatively flimsy plastic that vibrates when the compressor, fans, condenser coils, and other relays, switches, and valves click on and off. 

Jamming something, like a wood shim, between the case and the wall or window frame might deaden the vibrations. Or you could wear earplugs -- or just get used to the noise.  

Modern houses, built in the past 50 years, put the compressor outside in a small enclosure. The less noisy parts are inside the house. 

Several decades ago Albert Einstein, the atomic genius, and a an acquaintance,  Leo Szilard, future father of the hydrogen bomb, developed a novel  refrigerator that used heat to create cold. It consisted of three loops containing ammonia, butane, and water.  The device required no electricity.  Einstein was apparently interested in air conditioning due to a accidental release of refrigerant that  reportedly killed a family in Vienna in 1926.  

Einstein and Szilard refrigerator 
diagram

The descendants of the Einstein-Szilard refrigerator are now used in nuclear power plants, where the absence of moving parts more than compensates for the air conditioner's complexity.  

If price were no object could a quiet air conditioner be produced? A quieter one, sure.  It would be packed with noise-dampeningn foam, contain a carefully designed and balanced compressor, and equally precise fans, belts, tubing and so on. The quiet ar conditioner would probably cost as much as a new car, roughly speaking.  

As the greenhouse effect heats Earth to levels unprecedented since pre-history, think about how air conditioning works, about Einstein the inventor, and about how how delicious the sound of the window air conditioner clunking and buzzing away.  

Some air conditioners are quieter than others

 

 

  

Bitcoin, Money and The World of Make Believe

Confused by Bitcoin?

Of course you are!

That's really the whole point.  If you know about Bitcoin, you are likely a criminal, a would-be criminal, a law enforcement official, or one of the alleged people who created Bitcoin,

I do not understand Bitcoin, despite a perfunctory Google search. Bitcoin is a decentralized, anonymous database, or something like that.  Bitcoin has value because -- like actual money -- some people believe it does.

Speaking of actual money, like dollars and cents, consider how "real" they are.

You carry a wallet full of paper bills and a pocket with a few coins.  Is the paper and alloy inherently valuable? No.

 It represents something.

Money is as confusing and weird as Bitcoin, but we have become used to it,  Eons ago, someone realized that gold is in very short supply and hence, is inherently valuable.  Rarity seems to be the source of value -- supply and demand -- whatever that means.

Our currency is "backed" (?) by gold stored in Fort Knox, or that's how money used to be explained in school.  Seashells and other items were the first money, but they became impractical.  So someone, Adam Smith, perhaps, came up with a representational system.  A one dollar bill represents one actual dollar somewhere. Where? I don't know, but presumably someone like Paul Krugman does. 

Paper money is lighter than silver or alloy coins, so it is, our was, the way criminals bought and sold stuff. Money, inn theory, is untraceable and it is fungible, meaning that it can be used in other ways, like making small paper airplanes.

The New York Times, the newsprint version, explained today that our government was able to trace Bitcoins paid for ransom after cybercriminals seized a pipeline (how?) in the United States. The Department of Justice was apparently able to reclaim a large part of the ransom, by somehow determining the private password of the Bitcoin database or blockchain that the criminals used.

Bitcoin  is virtual, meaning it does not really exist, sort of like Britney Spears or the Royals. The stuff of Bitcoin is stored on servers somewhere, huge conglomerations of computers in storehouses in places like like Utah or Mars. 

So is our "money." So, in fact, is almost everything else not counting private property like cars and houses. I've read about arcane activities such as mining Bitcoin, which would make sense to people who'd understand Bitcoin.

If there are any.