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Oh , smart people , Joe .
Here , this is an active nuclear reactor and down there are uranium fuel rods undergoing fission reactions .
The blue glow that you see is not from the radioactivity itself .
If there's not some blue light bulb down there and make it look cool .
Oh , ok .
That was amazing .
I should probably explain what happened though .
You are watching what happens when matter travels faster than the speed of light .
Yeah , I'm serious .
I can already hear you typing your comments .
You may have heard that nothing can travel faster than the speed of light .
It's the fastest speed there is , right ?
Not exactly things can travel faster than the speed of light right here on earth .
And when that happens , it looks like this , that glow is the echo of matter moving faster than light speed .
It's true .
This bizarre phenomenon is real and this is how it happens without breaking any laws of nature .
Now to move something faster than the speed of light , there's one trick that you need to do first , you have to slow light down .
This is the number that we think of as the speed of light c but more accurately , this is just the speed of light travels in a vacuum .
And it's true .
Nothing can go faster than that .
But light doesn't always travel at that speed .
Anytime light travels through something transparent , it slows down .
Now , if you think about it , technically , whatever speed light is going is the speed of light .
But when that light passes through something like water glass , even air , it's not the fastest possible thing anymore .
The reasons why this happened are astonishingly strange and they require you to think about light a bit differently than you might be used to .
So why does light slow down when passing through stuff just going on intuition ?
You might think , ok , when a moving thing cruising along hits a denser material , it's going to get bogged down .
There's more resistance , right ?
As if you're sledding down an icy hill and you hit a patch of mud , you're gonna lose some speed .
But this isn't what happens to light .
Even though light slows down in a medium like glass , it comes out the other end and instantaneously , it's moving just as fast as it came in .
So that analogy with the sled doesn't quite work .
Maybe we can imagine photons of light passing through a medium bouncing off of particles like a pinball machine before popping out the other end .
If that were true light could still travel at sea , the fastest speed there is , but it would be taking a longer path from A to B which would take longer .
But if that were what was happening , a beam of light entering glass or water would get scattered in all different directions .
And that isn't what it actually does .
So our pinball model can't be right either to understand what's actually happening here .
We need to understand how electromagnetic waves like light travel across space .
You can think of a light wave as being made of both an electric field and a magnetic field .
Both are oscillating or wiggling in different directions .
These fields are directly related to each other .
A changing electric field produces a changing magnetic field which produces a changing electric field .
And so on this relationship between electric fields and magnetic fields is a fundamental property of the universe .
Now , as these two oscillating fields move across space , that is what is known as an electromagnetic wave .
The speed that this wave moves across space is determined by how well those wiggling electric and magnetic fields can create each other in a vacuum .
There's nothing to get in the way of this feedback loop .
So the electromagnetic wave we call light moves as fast as the universe will let it the ultimate speed limit C .
But if that light wave passes through a medium like water , the light's electric and magnetic fields jostle the atoms and molecules of the water to create their own electric and magnetic fields and well , that creates a mess .
All these fields tugging on each other essentially makes it harder for lights , electric and magnetic fields to generate each other .
Compared to if you're in a vacuum with nothing in the way , what we observe as a result of all of this is that whenever light passes through a transparent medium , it slows down , light travels at this slower light speed the whole way through the medium .
But because it doesn't get permanently altered by all of those other fields , it interacts with .
As soon as the light wave gets to the other end , it shoots back up to its original speed .
If your brain is hurting a tiny bit right now , that is a completely normal reaction .
This stuff is really weird .
Now , how much the light slows down depends on the material .
In air light travels just a smidge below the speed of light in a vacuum .
But in water , the speed of light is a full 25% slower and we can make particles travel faster than that , which is what is happening in a fission reactor .
And down below uranium is getting split apart and releasing a bunch of heat radiation and high speed particles like negatively charged electrons and their positively charged counterparts as positrons .
Now , as those charged particles move through water , whether they're going fast or slow , they pull on the water molecules so that the charges kind of align .
It's like if a celebrity walks through a crowd and everyone turns to look for a moment , all the bodies are aligned .
Then after they pass by , everyone turns back to whatever random direction they were facing .
You know , when those water molecules relax back to whatever orientation they were before the charge particle passed by , they give off a pulse of light .
If the charge particle is moving slower than whatever light speed is in that material , we can't really see that ripple of light just radiates outward and dissipates kind of like the ripples spreading around a swan that's drifting slowly across a lake on .
But now imagine the swan hits the turbo and starts screaming through the water faster than the ripples can expand .
The ripples get all bunched up along the leading edge .
This is a shock wave , we can see the same thing in 3D with sound .
If a jet or a bullet travels faster than the speed and the sound waves can travel , then those sound waves bunch up and create a shock wave that we hear as a sonic boom in the pool around the reactor , something similar is going on with light in that reactor , electrons and positrons can shoot out from those fission reactions faster than the speed of light in water .
And as those particles tug on the water molecules , the ripples of light given off are moving slower than the particle is .
So they pile up along that front edge , a shock wave just like a sonic boom except you see it instead of hear it a photonic boom .
Maybe that's what that blue light is .
The first person to see this that we know of anyway was Marie Curie .
But it wasn't until the 19 thirties that the Soviet physicist Pavel Chekov finally explained why it happens , which is why today we know this blue glow as Chekov radiation .
Now here in this nuclear reactor , Chekov radiation is mostly just a fun side effect .
But Chekov's discovery actually won the Nobel Prize in 1958 .
And one reason that it was so important was because it opened a whole new window to the universe every day .
High energy particles like neutrinos and cosmic rays launched long ago by distant supernovas stars and black holes rained down on earth , something like a million cosmic rays pass through your body every night while you sleep and trillions of neutrinos are flying through me and you , every second astronomers have been wanting to know where all these high energy particles come from for a long time .
Unfortunately , it's not that easy to study something that's not only invisible , but that whizzes by or through you at nearly the speed of light .
But luckily those high energy particles can give off sharing COV radiation .
So that gives us a way to see them .
Chekov detectors are big high tech thingies full of water as high energy particles shoot into them traveling faster than light can travel in that medium , they create a cone of Sharonov radiation like a wake that we can detect .
In other words , cherry Cov radiation , this strange phenomenon that happens when things move faster than the speed of light is literally shedding light on invisible realms of the universe .
That's pretty cool .
Think here it is .
I'm glowing with .
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When you think of inventions that define the world around us , the beauty and well-being industry might not be the first to come to mind .
But if you made a ven diagram of where beauty and technology meet , you'd find a company from Sweden called for they make skin care devices .
They sent me this one right here .
One thing it does is create what they call t sonic pulsations .
Basically , this makes low frequency vibrations that travel through the outer layers of the skin to help relax , facial and neck muscle tension improve blood flow .
This also has what they call microcurrent technology .
It creates a safe low voltage , electrical current , totally painless .
And there's dozens of muscles in your face and neck and that microcurrent stimulates those .
It's like it's like a workout for your facial muscles and skin that can tone and smooth out that epidermis .
You're always showing everybody .
This is called the bear by four .
It looks a little bit like a bear .
It's the world's first FDA cleared medical microcurrent device .
It's got an antishock system .
So if that ven diagram of beauty and science is something that you're into , you can check this out for you or as a gift , the bear by four is available online or in stores .
Just check the link down below for more info .
There you go .
Literally shedding light , which feels pretty good .
That's dumb .
Start this off with me .
Glowing blue like a happy face .
So excited .