upworthy

science

Why is text reversed in mirrors?

Have you ever wondered why text shows up backwards in a mirror? It's confusing to our brains because it doesn't seem like anything else is flipped like that. If we turn our head, it doesn't move the opposite direction in a mirror. Or does it? After all, right-handed you is actually left-handed you in the mirror. Right? (Wait, is that right?)

Mirrors can be confusing, despite not being very complicated. A mirror image is simply a reflection of what's before it. But when someone else is looking at us head on, they don't see text in reverse, so why don't we see what other people see when we see ourselves in a mirror?

Kitten Aww GIF by MOODMANGiphy

(If you think this is a super stupid question with a super obvious answer, congratulations. Pat yourself on the back and scootch along so the folks who don't fully grasp the physics of mirrors can enjoy a demonstration that makes it a little easier to understand.)

"Why do mirrors reverse text?" asks the creator behind @humanteneleven on YouTube. "You might think it's just a property of mirrors—they flip things from left to right—but that's not true." He then picks up a metal arrow to show that it points the same direction in the mirror as it does in real life. So why is the text flipped when the arrow isn't?

- YouTubewww.youtube.com

He then holds up a book to show how the text on the book cover appears backwards, just like the shirt. But when he holds up a Ziploc bag with the word "HELLO" written on it, the word shows up properly.

That's because he had to flip the book over to see the cover text in the mirror. The baggy he could just hold up and see the letters through the transparent plastic, just as we see them in real life. If he flips the baggy over like he did the book, the text shows up backwards in the mirror, just like it does in real life.

"So it's actually not the mirror that's flipping anything from left to right," he says. "It's the human."

People appreciated the simple, straightforward explanation and demonstrations.

"One of the most insightful demonstrations I've seen. It's simple and explains the phenomenon. Well done!"

"While I've heard this explanation many times before, I've only recently seen it demonstrated with text-on-transparency, which is what really makes it click. Great video!"

"Love these sorts of demonstrations. It’s a bit of a complicated one, but I love seeing how different people's minds work when explaining simple things like this. My kid explains it with “left is on the left, right is on the right, things aren’t flipped, they are mirrored” but it’s true that you are the one who flips things and I’ve never thought of it that way before."

"Oh my God, I haven't understood explanations from physics videos about why mirrors flip but this, gosh this helps."

Mirrors have been hilariously befuddling people in other videos as they try to figure out how the mirror knows what's behind a barrier placed in front of objects.

@sarahcoome

this is kinda creepy 👀 #mirror #relatable #creepy

Is this something all of us should probably have learned in high school? Yes. Do all of us remember everything we learned in high school? No. Does the scientific explanation make perfect sense to everyone even if it's explained in detail? Um, no.

Like the reversed text question, having a simplified explanation that doesn't fully get into the nitty gritty physics and geometry of how mirrors work is helpful for some folks.

- YouTubewww.youtube.com

For those who do want a bit more scientific substance to their explanations, this next video does a good job of giving a bit more detail while still keeping the explanation simple. It even uses a visual diagram to explain:

- YouTubewww.youtube.com

And for those who say, "This is so basic! How do people not understand this?" here's a video that really does get into the nitty gritty physics and geometry of how mirrors work, diving into ray and wave optics, photons, wave functions, probability, and quantum mechanics. It's only 12 minutes, and it manages to entertain while explaining, but it certainly blows the notion that understanding mirrors is super simple.

- YouTubewww.youtube.com

As one commenter wrote, "I thought I understood mirrors. I understand mirrors even less now. And that's a compliment."

Isn't science fun?


Science

Researchers hacked 5 people's brains so they could see a new and impossible color

The new color 'olo' is neat, but the technique behind it could be groundbreaking.

Canva Photos

Only five people in the world have seen the mysterious color "Olo"

Color is one of the great joys of being alive. The brilliant blue sky, the green grass, the exotic pinks and purples and teals in coral or tropical fish. Soaking it all in is truly a feast for the eyes, and some studies even show that certain colors can trigger specific emotions in people. Orange may evoke feelings of joy, and red may conjure feelings of love, while blue may have a calming effect.

One of the most interesting things about colors, though, is that they are finite. Though the world is full of undiscovered plants, creatures, and even elements, the entire color spectrum is known and documented. Due to the nature of light in our universe and how it reflects off of physical objects, all perceived color must be created by some combination of the primary colors (blue, green, and red — yes, green, not yellow!). There are essentially unlimited combinations, but they all exist on a known spectrum — different hues and shades of pink or emerald or orange.

However, a team of researchers recently decided to push the limits of human perception. They "hacked" participants' retinas to allow them to see an impossible color.


color, green, blue, color wheel, physics, light, wavelengths, scienceThe paint companies are dying to know the secret formula for the new color.Giphy

Scientists from the University of California, Berkeley, developed a new technique called "Oz," which would allow them to activate specific cones in the retina. Cones are light-sensitive cells that respond to different wavelengths of light. When the three types of cones are activated in different ways, our brains perceive colors.

One fascinating bit of background is that the "M" cone, which typically responds strongest to green (Medium wavelength), can not naturally be activated without also activating the Long and Short cones. So even the purest green on the planet would also, to a smaller degree, stimulate the parts of our eyes that are mostly correlated with red and blue.

retinas, eyes, oz, retina scan, retina cones, vision, colorsA close-up of the human eye. Swapnil Potdar/Unsplash

The team wanted to find out what would happen if they could isolate and activate only the M, or green, cone using the new technique.

The result? The five participants reported seeing an absolutely unreal, brilliant shade of green like nothing they had ever experienced. Imagine a bright green laser cranked up to the highest saturation and brilliance possible, the purest and brightest green your brain could possibly comprehend. Participants noted that a bright green laser pointed looked "pale" in comparison to the new color.

The name of the new, impossible color? Olo, or 010 (indicated zero stimulation of the L and S cones and full stimulation of the M cones).

- YouTubewww.youtube.com

It's fair to wonder, if olo is impossible and can never naturally exist without manual stimulation of the retinal cones, what's the point of the experiment?

The introduction of a "new color" is certainly interesting and makes for a good headline, but the real value of this study lies in the future applications of the Oz technique.

The research team hopes that the detailed retinal maps they have developed, along with their ability to stimulate specific rods and cones in the eye in any combination, will enable major breakthroughs in the study and treatment of various visual impairments.

For example, Oz could one day cure color blindness or unlock new treatments for cataracts or glaucoma. It could even play a role down the line in curing certain types of blindness. Isn't it wild how our understanding of how our eyes perceive color tells us so much?

But those days are a long way off, for now. In the meantime, only five people in the world have experienced the brilliance of olo, and the rest of us will just have to imagine it.

Pop Culture

A composer died in 2021, but a lab-grown version of his brain is still making new 'music'

Are the haunting tones proof of consciousness after death, or just a beautiful sentiment?

Guy Ben-Ary/YouTube & By Non Event - Alvin Lucier, CC BY-SA 2.0

Alvin Lucier''s "brain" is still composing music 3 years after his death.

I love the gag from Futurama where, when people die, their heads and brains are kept alive in a jar, allowed to carry on forever. Their body may have failed, but in a sense they can live on and on and on (as long as someone's there to lug them around). It's a fascinating idea, and one that's definitely being explored in various ways here in the real world.

For example, did you know that you can upload photos, videos, and audio clips of a deceased loved one and create an incredibly lifelike AI version of them? This may or may not be considered a good thing depending on how you view it, and though it's not true consciousness per se, it can be a frighteningly accurate blurring of the lines. Furthermore, some scientists insist that consciousness does not exist solely in the brain, and that one day we may be able to harness it when the living organs of the body have died. Heavy stuff!


futurama, brain, consciousness, immortality, longevity, scienceMaybe one day our heads will be able to live on in a jar!Giphy

A composer who passed away several years ago was also fascinated by the idea of his consciousness and art living on without him. So he devised a bizarre experiment.

The musician, composer Alvin Lucier, was not content to only make music for the duration of his natural lifetime. So he recruited a team from Harvard Medical School to harvest his stem cells after he passed away

From there, the stem cells were used to grow something resembling a clump of human brain matter. It's not a fully functioning brain, not even close, but it is living tissue derived from the DNA of the late musician. The experiment, then, was to determine just how much of Lucier really existed in this sample.

alvin lucier, composer, musician, music, orchestra, science, brain, immortality, deathAlvin Lucier passed away in 2021 at the age of 90By Non Event - Alvin Lucier, CC BY-SA 2.0

"The central question we want people to ask is: could there be a filament of memory that persists through this biological transformation? Can Lucier's creative essence persist beyond his death?" the team said, per the Art Newspaper.

Neuroscientists and artists teamed up to create an installation — part art, part science — called "Revivification." They connected the "in-vitro brain" to electrodes that would then transmit the electrical impulses generation by the brain matter to twenty humongous brass plates hung around, thus creating music. Or, at least, tones.

You can see the art installation and the behind the scenes in this video. If you want to hear the haunting tones that seem to originate from beyond the grave, you can get a listen at about 3:53.

- YouTubewww.youtube.com

Not only does the "organoid" generate signals that become sound through the brass panels, it also responds to the environment around it. Sound from the art gallery is captured by a microphone and fed back to the little mini-brain, which affects its electrode activity.

That makes the sounds generated inside the experiment totally unique and dynamic. If Lucier really "composing" this music, in a sense? Not really, but the bizarre sounds are being generated, in part, by his genetic material. That makes Revivification an absolutely fascinating blend of art, science, and maybe even a little spiritualism.

Revivification is probably not proof of consciousness after death, and it doesn't claim to be. But it asks interesting questions about the nature of memory, and where our creativity or spirit or soul or whatever you want to call it is really stored.

Perhaps the most touching aspect of the story is Lucier's unwillingness to ever stop creating new art, even after his death at the age of 90. You'd think that would be enough years to fully satisfy his need for self-expression! But not so.

When Lucien's daughter was told about the project, she laughed and said, "This is so my dad. Just before he died he arranged for himself to play for ever. He just can't go. He needs to keep playing."

John Mainstone was the custodian of the Pitch Drop Experiment for 52 years.

Because we use water all the time, most of us have an intuitive sense of how long it takes a drop of water to form and fall. More viscous liquids, like oil or shampoo or honey, drop more slowly depending on how thick they are, which can vary depending on concentration, temperature and more. If you've ever tried pouring molasses, you know why it's used as a metaphor for something moving very slowly, but we can easily see a drop of any of those liquids form and fall in a matter of seconds.

But what about the most viscous substance in the world? How long does it take to form a falling drop? A few minutes? An hour? A day?

How about somewhere between 7 and 13 years?

pitch drop experiment, tar pitch, solid or liquid, physics, world's longest experimentPitch moves so slowly it can't be seen to be moving with the naked eye until it prepares to drop. Battery for size reference.John Mainstone/University of Queensland

The Pitch Drop Experiment began in 1927 with a scientist who had a hunch. Thomas Parnell, a physicist at the University of Queensland in Australia, believed that tar pitch, which appears to be a solid and shatters like glass when hit with a hammer at room temperature, is actually a liquid. So he set up an experiment that would become the longest-running—and the world's slowest—experiment on Earth to test his hypothesis.

Parnell poured molten pitch it into a funnel shaped container, then let it settle and cool for three years. That was just to get the experiment set up so it could begin. Then he opened a hole at the bottom of the funnel to see how long it would take for the pitch to ooze through it, form a droplet, and drop from its source.

It took eight years for the first drop to fall. Nine years for the second. Those were the only two drops Parnell was alive for before he passed away in 1948.

- YouTubewww.youtube.com

In total, there have been nine pitch drops in the University of Queensland experiment. The first seven drops fell between 7 and 9 years apart, but when air conditioning was added to the building after the seventh drop, the amount of time between drops increased significantly. The drops in 2000 and 2014 happened approximately 13 years after the preceding one. (The funnel is set up as a demonstration with no special environmental controls, so the seasons and conditions of the building can easily affect the flow of the pitch.)

The next drop is anticipated to fall sometime in the 2020s.

pitch drop experiment, tar pitch, solid or liquid, physics, world's longest experimentThe first seven drops fell around 8 years apart. Then the building got air conditioning and the intervals changed to around 13 years.RicHard-59

Though Parnell proved his hypothesis well before the first drop even fell, the experiment continued to help scientists study and measure the viscosity of tar pitch. The thickest liquid substance in the world, pitch is estimated to be 2 million times more viscous than honey and 20 billion times the viscosity of water. No wonder it takes so ridiculously long to drop.

One of the most interesting parts of the Pitch Drop Experiment is that in the no one has ever actually witnessed one of the drops falling at the Queensland site. The drops, ironically, happen rather quickly when they do finally happen, and every time there was some odd circumstance that kept anyone from seeing them take place.

The Queensland pitch drop funnel is no longer the only one in existence, however. In 2013, Trinity College in Dublin, Ireland, managed to capture its own pitch drop on camera. You can see how it looks as if nothing is happening right up until the final seconds when it falls.

- YouTubewww.youtube.com

Today, however, with the internet and modern technology, it's likely that many people will be able to witness the next drop when it happens. The University of Queensland has set up a livestream of the Pitch Drop Experiment, which you can access here, though watching the pitch move more slowly than the naked eye can detect is about as exciting as watching paint dry.

But one day, within a matter of seconds, it will drop, hopefully with some amount of predictability as to the approximate day at least. How many people are going to be watching a livestream for years, waiting for it to happen?

PoorJohn Mainstone was the custodian of the experiment for 52 years, from 1961 to 2013. Sadly, he never got to witness any of the five drops that took place during his tenure. Neither did Parnell himself with the two that took place while he was alive.

John Mainstone, pitch drop experiment, university of queensland, physicsJohn Mainstone, the second custodian of the Pitch Drop Experiment, with the funnel in 1990.John Mainstone, University of Queensland

Sometimes science is looks like an explosive chemical reaction and sometimes it's a long game of waiting and observing at the speed of nature. And when it comes to pitch dripping through a funnel, the speed of nature is about as slow as it gets.