Christian Schirm/Public Domain
Christian Schirm/Public Domain

The Art of Schrodinger’s Cat

Christian Schirm/Public Domain
Christian Schirm/Public Domain

Erwin Schrödinger posited a thought experiment in 1935 that became known as Schrodinger’s Cat. You put a cat in a box with some equipment and shut it up. Inside, there is a radioactive element that has a 50% chance of decaying in an hour. Any decay will register on a Geiger counter, which trips a device that breaks a poison vial and kills the cat. But the box is closed. At the end of that hour, is the cat dead or alive? You cannot know until you open the box. Therefore, until you observe the cat, he exists as both dead and alive.

ADA&Neagoe via Wikimedia Commons // GFDL

To the layman, that seems ridiculous. Schrodinger’s experiment is about quantum mechanics, but it's like philosophy and metaphysics as well. If a tree falls in the forest, and no one is there to hear it, does it make any sound? Of course it does, because believing that nothing exists outside our perception of it is extreme hubris.

Be that as it may, the experiment seems unnecessarily cruel as well as absurd. Schrodinger was a smart man, but that's no excuse to kill a cat. Despite the fact that it was just a thought experiment, Schrodinger's reputation took a hit from both cat lovers and slightly-less-sharp scientists, as you can see in this T-shirt designed by Mike Jacobsen.

Another Dimension

The explanation for those somewhat familiar with quantum mechanics reveals that Schrodinger was just trying to make a point among physicists. But the thought experiment lingered on, because we love cats, and would hate to see harm come to one. And the idea of a cat being both dead and alive bends our brains. It’s like a trip into another dimension.

A T-shirt from Wear Viral entitled Schrodinger’s Portal puts the cat into the physics-bending world of the game Portal.

F. Gwynplaine MacIntyre created this illustration for his short story "Schrödinger's Cat-Sitter.” The cat is simultaneously in front of and behind the impossible object, which makes about as much sense as the cat being both dead and alive at once.

Artist Jie Qi saw that the two states of the cat, alive and dead at the same time, were impossible. He illustrated that as an illusion, putting the cat inside an impossible box as well. This drawing is from 2006. He followed that up with two more iterations of the same subject you can see here, and you’ll find the original version from 2004 here

How can a cat be both dead and alive? DeviantART member Evilkitten3 saw that as a condition that could be desired, even if it’s not possible.

It’s quite a difficult concept, especially when you first hear it. A group of giant robots learn about the Schrodinger’s Cat experiment and decided to investigate the results for themselves, in this Robot Republic video.  

Comic artist Hannah Blumenreich considered the entire idea silly, because a cat will let you know when he doesn’t want to be in the box anymore. If he is alive, that is.

Half Dead, Half Alive

Some interpret “both dead and alive” to mean half dead and half alive, because that’s the only way the phrase makes any sense. DeviantART member atoji saw that as a literal way to illustrate the cat. Maybe he's only mostly dead.

DeviantART member RaggedyAnarchist used the same idea, with the cat split down the middle and the “dead” side still holding the poison that killed him. Or half of him. The other side is celebrating life!

When Cecil Adams of The Straight Dope received a rhyming letter asking him to explain Schrodinger’s Cat many years ago, he replied with an epic poem that didn’t clear up anything at all, but it rhymed well. Here the poem appears with Scott Adams’ Dilbert comics featuring Schrodinger’s cat. I have no idea whether Cecil Adams is related to Scott Adams.  

The Zombie Cat

But there’s another way to be both dead and alive, as we’ve seen in some George Romero films and the TV series The Walking Dead. The cat could be a zombie! Alive, meaning animated, and dead, meaning he died in the box. DeviantART member pixelat3dLtd illustrated Schrodinger’s zombie cat, who seems to be looking for the one who caused his current state of being.

Taking that idea a step further, DeviantART member Zaleho made Schrodinger’s cat a zombie with one side “deader” than the other, sporting saber-teeth as well!

The Cat’s Revenge

How does the cat feel about being treated in this way? Not happy, as illustrated by Matthew Inman of The Oatmeal. The cat is justified in wanting to turn the tables on the scientist who thought up the experiment.  

Animator Chavdar Yordanov tackled the subject in 2012 with a video exploring the wrath of the formerly adorable cat who is subjected to such an inhuman experiment. The mayhem inflicted by the ghost of the wronged feline is rather satisfying.

But we all know how the experiment really would have turned out. The cat is, of course, alive, because cats have nine lives!

See also: The Buttered Cat Paradox

Animal Welfare Groups Are Building a Database of Every Cat in Washington, D.C.

There are a lot of cats in Washington, D.C. They live in parks, backyards, side streets, and people's homes. Exactly how many there are is the question a new conservation project wants to answer. DC Cat Count, a collaboration between Humane Rescue Alliance, the Humane Society, PetSmart Charities, and the Smithsonian Conservation Biology Institute, aims to tally every cat in the city—even house pets, The New York Times reports.

Cities tend to support thriving feral cat populations, and that's a problem for animal conservationists. If a feline is born and grows up without human contact, it will never be a suitable house cat. The only options animal control officials have are to euthanize strays or trap and sterilize them, and release them back where they were found. If neither action is taken, it's the smaller animals that belong in the wild who suffer. Cats are invasive predators, and each year they kill billions of birds in the U.S. alone.

Before animal welfare experts and wildlife scientists can tackle this problem, they need to understand how big it is. Over the next three years, DC Cat Count will use various methods to track D.C.'s cats and build a feline database for the city. Sixty outdoor camera traps will capture images of passing cats, relying on infrared technology to sense them most of the time.

Citizens are being asked to help as well. An app is currently being developed that will allow users to snap photos of any cats they see, including their own pets. The team also plans to study the different ways these cats interact with their environments, like how much time pets spend indoors versus outdoors, for example. The initiative has a $1.5 million budget to spend on collecting data.

By the end of the project, the team hopes to have the tools both conservationists and animal welfare groups need to better control the local cat population.

Lisa LaFontaine, president and CEO of the Humane Rescue Alliance, said in a statement, “The reality is that those in the fields of welfare, ecology, conservation, and sheltering have a common long-term goal of fewer free-roaming cats on the landscape. This joint effort will provide scientific management programs to help achieve that goal, locally and nationally."

[h/t The New York Times]

How Does Catnip Work?

If you have a cat, you probably keep a supply of catnip at home. Many cats are irresistibly drawn to the herb, and respond excitedly to its scent, rubbing against it, rolling around on the floor, and otherwise going nuts. There are few things that can get felines quite as riled up as a whiff of catnip—not even the most delicious treats. But why does catnip, as opposed to any other plant, have such a profound effect on our feline friends?

Catnip, or Nepeta cataria, is a member of the mint family. It contains a compound called nepetalactone, which is what causes the characteristic catnip reaction. Contrary to what you might expect, the reaction isn’t pheromone related—even though pheromones are the smelly chemicals we usually associate with a change in behavior. While pheromones bind to a set of specialized receptors in what’s known as a vomeronasal organ, located in the roof of a cat's mouth (which is why they sometimes open their mouths to detect pheromones), nepetalactone binds to olfactory receptors at the olfactory epithelium, or the tissue that lines the mucus membranes inside a cat’s nose and is linked to smell.

Scientists know the basics of the chemical structure of nepetalactone, but how it causes excitement in cats is less clear. “We don’t know the full mechanisms of how the binding of these compounds to the receptors in the nose ultimately changes their behavior,” as Bruce Kornreich, associate director of the Cornell Feline Health Center, tells Mental Floss. Sadly, sticking a bunch of cats in an MRI machine with catnip and analyzing their brain activity isn’t really feasible, either from a practical or a financial standpoint, so it’s hard to determine which parts of a cat’s brain are reacting to the chemical as they frolic and play.

Though it may look like they’re getting high, catnip doesn’t appear to be harmful or addictive to cats. The euphoric period only lasts for a short time before cats become temporarily immune to its charms, meaning that it’s hard for them to overdo it.

“Cats do seem to limit themselves," Michael Topper, president of the American Veterinary Medical Association, tells Mental Floss. "Their stimulation lasts for about 10 minutes, then it sort of goes away.” While you may not want to turn your house into a greenhouse for catnip and let your feline friend run loose, it’s a useful way to keep indoor cats—whose environment isn’t always the most thrilling—stimulated and happy. (If you need proof of just how much cats love this herb, we suggest checking out Cats on Catnip, a new book of photography from professional cat photographer Andrew Martilla featuring dozens of images of cats playing around with catnip.)

That said, not all cats respond to catnip. According to Topper, an estimated 70 percent of cats react to catnip, and it appears to have a genetic basis. Topper compares it to the genetic variation that causes some individuals to smell asparagus pee while others don’t. Even if a cat will eventually love the smell of catnip, it doesn’t come out of the womb yearning for a sniff. Young kittens don’t show any behavioral response to it, and may not develop one until several months after birth [PDF].

But some researchers contend that more cats may respond to catnip than we actually realize. In one 2017 study, a group of researchers in Mexico examined how cats might subtly respond to catnip in ways that aren’t always as obvious as rolling around on the floor with their tongue hanging out. It found that 80 percent of cats responded to catnip in a passive way, showing decreased motor activity and sitting in the “sphinx” position, an indicator of a relaxed state.

There are also other plants that have similar effects on cats, some of which may appeal to a wider variety of felines than regular old catnip. In a 2017 study in the journal BMC Veterinary Research, researchers tested feline responses to not just catnip, but several other plants containing compounds similar in structure to nepetalactone, like valerian root, Tatarian honeysuckle, and silver vine. They found that 94 percent of cats responded to at least one of the plants, if not more than one. The majority of the cats that didn’t respond to catnip itself did respond to silver vine, suggesting that plant might be a potential alternative for cats that seem immune to catnip’s charms.

Despite the name, domestic cats aren’t the only species that love catnip. Many other feline species enjoy it, too, including lions and jaguars, though tigers are largely indifferent to it. The scent of the plant also attracts butterflies. (However, no matter what you’ve heard, humans can’t get high off it. When made into a tea, though, it reportedly has mild sedative effects.)

The reason Nepeta cataria releases nepetalactone doesn’t necessarily have to do with giving your cat a buzz. The fact that it gives cats that little charge of euphoria may be purely coincidental. The chemical is an insect repellant that the plant emits as a defense mechanism against pests like aphids. According to the American Chemical Society, nepetalactone attracts wasps and other insect predators that eat aphids, calling in protective reinforcements when the plant is in aphid-related distress. That it brings all the cats to the yard is just a side effect.

Because of this, catnip may have even more uses in the future beyond sending cats into a delighted frenzy. Rutgers University has spent more than a decade breeding a more potent version of catnip, called CR9, which produces more nepetalactone. It’s not just a matter of selling better cat toys; since catnip releases the compound to ward off insects, it’s also a great mosquito repellant, one that scientists hope can one day be adapted for human use. In that case, you might be as excited about catnip as your cat is.

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