Why Are Some Things Transparent?

[@Jule-mm4dr]

photon's seducing scenes really made me laugh.

[@Dom-gf4in]

Jusuf Kovacevic “size has been exaggerated so you can see everything.”

[@ScienceAsylum]

Михаил Лебедев: Actually, glass is most definitely a solid. It's just not a crystalline solid. It's an amorphous solid. I would have liked to reply to your comment directly, but your privacy settings must be preventing it.

[@davidndiulor8428]

Amorphous?¿

[@ScienceAsylum]

David Ndiulor "amorphous" means that the bonds aren't regular. The molecules form solid bonds, but there's no real pattern to it. They just kind of form wherever they want.

[@terminate5888]

The Science Asylum why is glass opaque to infrared ? Your explanation cannot be the whole story as we know infrared has less energy that visible light but is still absorbed

[@WarrenGarabrandt]

​@@terminate5888 Remember the part where the photons are everywhere bouncing all around, but destructively interfere with each other everywhere except certain paths? Those paths are where the visible light can get through, and be seen, hence transparent. Different wavelengths (colors) of light will do this in different ways in different materials. This is why prisms and water droplets can split the different colors of light into a rainbow; different wavelengths constructively and destructively interfere with each other at different places, so very long wavelength radio waves can go through the glass relatively unchanged, Microwave light like WiFi gets severaly attenuated by most kinds of glass, infrared light gets nearly completely absorbed (opaque), visible light gets very slightly distorted and attenuated, but make it through for the most part, and ultraviolet gets mostly absorbed, etc.. You can measure how much each wavelength would be affected by different materials, but I don't know if it's possible yet to actually predict how new materials will respond to any given wavelength. We have entire branches of science dedicated to the study of materials to determine these properties.

[@terminate5888]

@@WarrenGarabrandt, Your forgot energy levels. The interference in only part of it. Infrared is absorbed because there is more than one electron orbital and so can absorbed IR light. The interference only explain why certain paths are taken. But photons take paths an entire 360 degrees with respect to the axis of the beam going into the medium, hence why you can see the beam. Although i'm quite intrigued on how the paths are taken differently like this, do you know a paper on this?

[@alexroberts4887]

This is hands down one of my favourite science channels on KZbin

[@motobazuka2535]

I actually love how I just learnt why glass absorbs a lot of UV radiation! Thanks

[@ScienceAsylum]

You're welcome!

[@SeongeunHyun-qs8fs]

So does that mean every glass is basically sun screen?

[@fallendown8828]

Me too

[@AnnaS1371]

I found your videos a few days ago and have been watching them since! Love the graphics, humor and fun explanations; great way to learn science for sure 😊. Anyway, I have a suggestion for a video... How about an explanation of why things appear transparent while they spin (i.e.: a fidget spinner, a fan, or tire rims)? Just an idea 💡

[@ScienceAsylum]

Glad you like them :-)

[@CT-pi2gl]

That must be why X-rays and Gamma rays are used to see through things - they have a high enough energy to jump the band in almost any material. Nearly everything is transparent in X-ray. Fascinating how everything ties together!

[@OldDemonTooth]

Yes. That must be! The EXACT reason he explained is THE reason they can and do work like this...

[@VeronicaGorositoMusic]

Exactly.

[@Djanoko]

Bones are not transparent to X-rays. If they were, you would see nothing on an X-ray scan.

[@SyDatNguyen-r4j]

Yeah, and also since bones is denser, x-rays get blocked, so it allows white images to appear on screen

[@isivonov]

Thanks! I started to review all your older videos.. and this was mindblowing for me...

[@hperantunes]

That's the best explanation I've ever had to this subject!

[@UpusCumupus]

I always enjoy watching your videos and seeing your channel grow.. Keep up the good work!

[@cheeseweasel69]

Great video, I am amazed at how well explained that all was!

[@ScienceAsylum]

Thanks!

[@tmdrake]

Good explanation...I love this channel!

[@fdntrinity]

You're really at the right wavelength! Absorbing the wisdom from your videos makes me really excited and I run around my house! No seriously tho, I really enjoy your videos. Learning about physics in such a fun and informative way really makes me happy and excited everyday! Thank you so much!

[@Dom-gf4in]

Me, innocently: Why isn’t everything transparent? Nick Lucid: Electrons are greedy little...s.... Me: Little whats? 🐣💩💛

[@markandrews1219]

Love your crazy explanations because beyond entertaining, your science is very strong.

[@numankaraaslan]

damn :D it is a lot more complicated than i thought :D

[@ScienceAsylum]

That's how I felt when I researched this.

[@marcuspradas1037]

I think that s the best short explanation about transparency I ve ever seen.

[@braa194332]

Does the photon emitted from the electron have the same linear momentum as the one absorbed?

[@ScienceAsylum]

If it transitions between the same two states, yes... but it might not. Fluorescence is an example of when it doesn't.

[@cosmotect]

Wow, what an awesome video. It pays to stray from bigger science channels!

[@q-tuber7034]

“Let me make something- very- CLEAR.”

[@මලින්දසමරසිංහ]

Excellent explanation Sir

[@DeonChristofferse]

This content was exactly what I needed!

[@Bharathkumar-od9je]

this is the cutest thumbnail of all your videos ..

[@ScienceAsylum]

😂 Thanks.

[@MarcoAGJ]

This is the better explanation yet.

[@crocoduck2684]

Very nice and complete explanation! Thanks!

[@ScienceAsylum]

You're very welcome!

[@mklik4]

I always lose you in the middle of the clip. You still make it interesting and worth watching. I hope to someday understand the complete video

[@krisinsaigon]

I just disovered your channel by accident and am really enjoying it, thanks for these. this is the kind of thing i'm alwayd wondering about In answer, the worst glass thing i ever broke was a huge very expensive brand new etched glass shop front in a vietnamese brothel. it had a door, and i pulled it open instead of pushing it open and the whole thing got a big crack all down it and shattered inside then i had to wait while a very intimidating gangster was sent for to encourage me to pay for the repairs

[@kiratchawla1386]

This channel is really gr8 keep up the good work.

[@benjaminsharef6589]

The worst glass-thing I ever broke were those fill-up glasses from mobile stations. For those of you old enough to remember, Mobile Gasoline stations used to offer a large glass if you filled up your car at one of their stations. These glasses were AWESOME! Unfortunately, they always seemed to break except for one (like you couldn't have more than one in your house or something). Eventually they all broke at my house. When my grandmother passed away, we got another from her to go along with our lone survivor. Not a month later, one of them broke...not sure what the scientific explanation is for that, but that's how it went down.

[@UTArch1]

Grew up poor - all our drinking glassware were these give-away glasses. We had LOTS of them in several sizes.

[@sumitkc7069]

wow,so very clear and lucid.

[@jlpsinde]

Great video!

[@Henry14arsenal2007]

Whats really interesting is that while electrons might release the absorbed photons in every direction and most cancel out and so we only see the ones going in the other direction, it all happens instantaneously fast. Like imagine if some electrons would get stuck releasing photons back into the incoming direction for a couple of seconds, imagine not seeing a reflection in the mirror then it suddenly appears or not being able to see through a glass of water.

[@rasanmar18]

A bit fast at the end. However, I could understand it by replaying it. Very good video as always.

[@ScienceAsylum]

Yeah, my older videos are like that... just a _little_ too fast.

[@deltabeta5527]

Wow amazing video! Satisfied my curiosity

[@GustavoMouraD]

Best definition ever

[@btbb3726]

A Lucid explanation in the interest of transparency.

[@ianstephens5338]

You deserve more subs

[@felipedegodoynigro4025]

You channel is the best!

[@ScienceAsylum]

Thanks!

[@Jackrodder]

I was just drinking a glass of water, and during that I looked outside the window. When suddenly, me, the grown ass man, 25 years old googled "How are things transparent?". Here I am, let's hear it. Edit: Video done. Well, Tomorrow I'll definitely won't be able to repeat everything that you said, but it became understandable. Nice!

[@karthikeswara8441]

Wow. Great video!

[@grideffect1193]

great video, fun video, clear!

[@lewisjones2825]

Different from my guess--that light gets through if the wavelength matches the substance's atomic pattern, like a sine wave not hitting items in a grid

[@anthonysandoval9275]

Omg!!! It DOESN’T matter what my day is like, or what the subject matter is that your explaining, you are so funny dude! The worst glass thing I broke was a glass cake pan, I spilled a glass of water on the stove where I had se it after pulling it out of the oven, and it broke into SO many pieces!! Had to throw the food out too… sad 😢 N-E way !!! Thanks again for all your hard work, and hilarious videos!! 👍

[@lidarman2]

This video is definitely more satisfying than another one you made about why light seems to slow in solids. But in your other video, you seem to indicate there is no momentary absorption and re-emission.

[@ScienceAsylum]

Vibrating entire atoms takes energy. That energy comes from the incoming light, so the incoming light doesn't make it very far in the glass. I need to revisit the light speed topic now that I'm using Adobe CC instead of Sony Vegas.

[@uxinox58]

Great Video. Thanks.

[@adityachk2002]

It had a boring title but amazing content

[@marcushendriksen8415]

The worst glass thing I've ever broken? A classroom window, probably. It was lunchtime and only me and my mates were inside. We were passing a basketball to each other, it came to me too low, so I unthinkingly kicked it. Now, not being a professional footballer my aim isn't the greatest, so instead of going where I'd have liked it to, it stubbornly went on a collision course with the window.

[@akilghosh]

Guess having him for a professor. Wow!

[@definesigint2823]

Imagining the awesome.

[@peckelhaze6934]

Very funny and educational.

[@CaritasGothKaraoke]

@Fermilab says your explanation of refraction is wrong, and also that light really does slow down whilst passing through matter, because it gets a sort of wave drag from the electromagnetic field of the matter through which it’s passing.

[@JB-ux3ri]

Good video, thank you. Is this the same for plastic too? Plastic is a solid isn't it?

[@ScienceAsylum]

You mean for transparency in plastic? Yes. If you're looking for a deeper answer, you should check out this video: kzbin.info/www/bejne/Z5_CoKd_qJutbKc

[@50rri50]

i broke a german millikan experiment oil sprayer. i panicked for a few hours since it was brand new, but i managed to fix it in a glass shop.

[@edwinjamesmartinarbulu7801]

One question. When a frequency of light passes through a transparent material or molecule, because it does not coincide with that of its resonance, is it true that the light passing through it is of a lower intensity or amplitude because it has been reduced due to the work of the restoring force of the molecule?

[@BelaLieder]

Hello. Is the non resonant absorption, you talk about, the same as the dissipative absorption in "why aren't mirrors white?"? Because electrons can't absorb photon, if they have the wrong energy (a too low energy), that's the whole point, isn't it?

[@saisriramgovardhanam302]

explain the thing about energy bands in solid,liquid,gases clearly!

[@ScienceAsylum]

Energy bands should only happen in solids.

[@ankokuraven]

Simple answer "Transparency depends on what wavelength of light you are considering, the substance, and its thickness." Things we call transparent are transparent to visible light. There are plenty of types of light that make it through walls. Just not the kinds you can see with human eyes.

[@mandisaplaylist]

3:48 I would be careful with the wording here. "Absorbed" means the quantum state of the photon is lost (or, to be extract, merged with the quantum state of the electron) as the photon is destroyed and its energy transferred to the electron. A better wording would be "it still interacts" (causing the photon to slow down) but it is in fact not "absorbed" (it still exists during and after the interaction, along its quantum state, sometimes predictably modified (like in the refraction/reflection where the photon changes direction)).

[@anshul9462]

Why light gets reflected? Most of atom and space between atoms is an empty space. What makes a photon (or if considering light as wave then why wave) bounce off the reflecting surface? Which makes us see as reflection.

[@ScienceAsylum]

You Don't Know How Mirrors Work: kzbin.info/www/bejne/qIqvq6uZipuFha8 Why isn't EVERYTHING a Mirror? kzbin.info/www/bejne/Z5_CoKd_qJutbKc

[@mybluemars]

Electrons and Photons are both point particles. We are talking about elementary particles that have no mass interacting with each other. The math and quantum predictions work out beautifully, but I don't know how, because they really don't exist!

[@subhrajitnandi5447]

Perfection this is

[@tommyvictorbuch6960]

Wouldn't it be cool, if you presented yourself as Nick Lucifer? It seem to fit a mad scientist, and I almost hear that name every time. But then again, I'm Danish. What the heck do I know. Great videos. Keep 'em coming, Nick.

[@e8root]

only 12k views? world is crazy!

[@shreyanshu9785]

Finally i get the answer to why wifi can pass through walls unlike those videos that say they can because they are radio waves

[@ScienceAsylum]

Glad I could help 🤓

[@christiantemple7403]

0:53 "if energy is definite, then position is not " In pilot wave theory (or DeBroglie-Bohm theory), electrons have definite positions at any moment of time. It's an equally valid interpretation of experimental data and makes exactly the same probabilistic predictions as that of Quantum Mechanics.

[@ScienceAsylum]

Bohmian mechanics is far too incomplete to compete with Copenhagen at the moment. Maybe in time.

[@christiantemple7403]

Sure, that's because not so many people work on it. No complete relativistic version of it exists yet. However, the majority of philosphers favor bohmian mechanics over Copenhagen interpretation. Sheldon Goldstein at Rutgers university along with others published lots of papers on it.

[@mrstevecox7]

When the photon is "absorbed" in the second case (where the electron does not jump an energy level), and "immediately rejected", is it the same photon?

[@GulzarAhmad-sw1kh]

I think it isn't 'absorbed' but an attempt of photon to interact with electron that failed - the interaction is probabilistic!

[@SkylerLinux]

When I was a kid we had these "shatter proof" glasses, supposed to not shatter if they broke just supposed to be like two or three big pieces. When ever one broke they practically atomised.

[@wordsshackles441]

Question: If both "reflection" and "transmittance" are the result of "non-resonant" absorption - What makes an opaque material (say a white sheet of paper) reflect light instead of transmitting it? Also, is the reflective property of metal due to non-resonant absorption as well?

[@ScienceAsylum]

I just a did a video about this: kzbin.info/www/bejne/Z5_CoKd_qJutbKc 🤓

[@유지태-l9s]

What's not transparent? Does it have every energy level differences for every visible light? Is it possible?

[@psychachu]

Cool, that actually clicked. Thanks! :)

[@bili4591]

Why infrared wave carry heat ? why when an electron from an atom of hydrogen ( for example ) absorb a photon and jump to the next level, and he must go back to the initial level and emitted the photon back, why we don’t see a continuous spectrum ? if the electron go back, the photon is re-emitted so... why there is a black line ? And ... what is color in a normal case ? no heat gaz, just the color of an object that we see ( no mirror, no glass ). Please.

[@victorbian3594]

You are like the wheezywaiter of science

[@ScienceAsylum]

Victor Bian That's a huge compliment :-)

[@victorbian3594]

***** you're welcome, this channel could become something amazing if you work towards it

[@CaritasGothKaraoke]

If electrons are points with no volume at all, but they have mass, then shouldn’t they have infinite density?

[@fins59]

And the difference between transparent and opaque plastic is?

[@spnkrr]

How do we take this info and create other transparent materials... like metals?

[@Nakameguro97]

Do a video on invisible cloaks!

[@JavedAli-ik6ux]

hi nick, i am big big fan of yours, i am watching your content for a very long time, i very enjoy your videos, i watch them several times and all the time i learn something new, my request is, kindly respond to my question in the comment section of this video. Thank you.

[@ScienceAsylum]

Glad you like my work 🤓

[@JavedAli-ik6ux]

@@ScienceAsylum kindly answer my question "so in which of those two phenomenas, (absorption of photon with the right energy, or the one with a lesser energy) results in the variation of frequency of light? In one of your video you mentioned that whenever light interacts with mater, the mater itself then produces light and then the incident light and the light produced by the mater interfere and we get the resultant light with slower or faster speed and changed direction. Does this causes in change in frequency as well? if not what causes the change in frequency of the incident light?"

[@Humansince2004]

Wavelength of red slight is .650nm am I right or not????? Pls reply

[@Djanoko]

You're saying the gap between energy bands is too big for light, but then how does infrared gets absorbed?

[@ScienceAsylum]

Infrared has a lower frequency, so it can allow electron to jump levels _within the same energy band._

[@robertovalenzuela8860]

I saw two physics youtube channels and they explained that's because the constructive interferience of the light electric field and the electron electric field, so, one is faster than the other and when they combined the energy travels at a low speed, but maybe that means that the frequency and wavelength may change its magnitude at the time it is inside the material. So, could the non-resonance absortion be the same phenomena? just a combination or constructive interferiences of both electric fields ?

[@simphiwemalinga5869]

This guy is good.

[@Dagnostic]

The worst glass thing (things.... so many things) I've broken...? A quartz furnace liner for a semiconductor factory. Thermal shock and quartz resonance are a bitch. Great channel by the way, stay awesome.

[@gtggj6851]

Lets be clear about it glass is not transparent for uv light right?

[@akh345]

At 3:29 the explanation for transparency of glass was that "the gap of 9 eV is too big for visible light". But how can this be the explanation if glass stops being transparent in thermal infrared (that have even lower energy photons)?

[@ScienceAsylum]

Energy level differences in the infrared are available below (and above) the "9 eV gap" because they're tiny jumps. The visible range jumps are bigger and would require there be energy levels in that "9 eV gap."

[@akh345]

I see. Thanks a lot for your reply, Nick! But isn't glass transparent again in microwave (radiofrequency) range? Say, my car's radar detector (K-band, Ka-Band and X-band) works absolutely fine behind the glass. My FLIR camera on the other hand can't see anything through the glass. The microwave photon should have even tinier step. I am lost... (And if glass is not transparent in microwaves then glass would not work in microwave ovens?)

[@lemont2005]

You really have to do a recall to all physics teachesr from Brazil .

[@JavedAli-ik6ux]

so in which of those two phenomenas, (absorption of photon with the right energy, or the one with a lesser energy) results in the variation of frequency of light? In one of your video you mentioned that whenever light interacts with mater, the mater itself then produces light and then the incident light and the light produced by the mater interfere and we get the resultant light with slower or faster speed and changed direction. Does this causes in change in frequency as well? if not what causes the change in frequency of the incident light?

[@davidebusato2476]

I destroyed two windows at my grandma's using a wood log... never got so many slaps in my life: my grandma, my mum, and my dad...

[@truthlover6079]

Now someone please explain what are the energy bands?

[@ScienceAsylum]

I explain those bands in more detail here: _Does Electricity REALLY Flow?_ kzbin.info/www/bejne/h3zblqNuZ8RsmJo

[@truthlover6079]

@@ScienceAsylum Thank you :)

[@rakibahmed6249]

Thanks!

[@ScienceAsylum]

You're welcome!

[@InsaneDeck]

About the wavelength that glass absorbs, does this depends on the type of glass? From experience I know that glass blocks UV radiation (from around 300 nm and lower wavelengths), but objects made of quartz are transparent to UV (at least down to 190 nm, which is as far as I measured).

[@ScienceAsylum]

You are correct. This effect does depend on the type of glass and it also doesn't block all UV (only some).

[@ganeshachaturvedi7975]

Is there a possibility of mutual cancellation of the magnetic fields generated by two charged particles by superposition? This ques is from Astha from India 🇮🇳, ur follower on Twitter

[@ScienceAsylum]

It happens all the time with magnetic fields generated by the quantum spin of particles in atoms. That's why atoms tend not to be magnetic.

[@galileofrank5779]

So every photon that passes through the electron cloud gets absorbed? Wouldn't some of the photons enter the cloud and cause the electron's wave function to collapse its position somewhere where it can't absorb the photon? In the bus seat analogy it would be like if you sat down in one of the 3 seats taken up by the electron wave function and the electron then "collapses" into just occupying the seat next to you, by chance.

[@ScienceAsylum]

There's more than one type of "absorption." I talk about them in more detail in a more recent video: kzbin.info/www/bejne/Z5_CoKd_qJutbKc

[@neurodivergentsophie8411]

What do you mean by the photons interfering and cancelling eachother?

[@ScienceAsylum]

This might help: "Why isn't EVERYTHING a Mirror?" kzbin.info/www/bejne/Z5_CoKd_qJutbKc

[@jonathanlange1339]

I love your work! And you are very funny :D

[@刘开元-w2l]

So, why is snow untransparent but water is transparent? does it means the electron rejection has a direction?

[@ScienceAsylum]

This is actually a video topic I've had on my list for a while. It might be time to do it soon :-)

[@bedooelbatal573]

Thanks

[@GreatBigBore]

At 2:15, isn't the thermal energy in a liquid/solid also a photon? Like, infrared? Or is it just molecules bumping into each other? And If they're just bumping, at some point do they start emitting infrared as they bump harder and harder into each other?

[@ScienceAsylum]

Thermal energy in solids, liquids, gases, and plasmas is just the kinetic energy of the particles in the substance. Infrared photons are certainly involved in the _transfer_ of that thermal energy from one place to another, but those photons are not the the thermal energy themselves.

[@shikhararora4363]

Since energy is definite, position is not? Is there a correlation between energy and position that I should know about?

[@ScienceAsylum]

It's not very well known, but it does exist. There are _lots_ of commutator relations, but two of them hog all the attention: position-momentum and time-energy.

[@shikhararora4363]

@@ScienceAsylum Man ur so cool.

[@stacysilverman6366]

But what's the mechanism for reflection as opposed to transmission? What happens to incoming light on the surface of, say, copper (where the solid is essentially a pool of free electrons), that causes the light to get redirected back toward the viewer as opposed to what happens when incoming light hits, say, silicate glass, where it is only refracted and passes through the material?

[@ScienceAsylum]

That's a complicated question that depends on how the material behaves. Things like atoms/molecular spacing, delay time in response to light, etc. Maybe I'll get around to doing a video on it this summer.

[@moiquiregardevideo]

You will notice that reflecting material are also good electric conductor. Electromagnetic waves, like all other waves, reflect when encountering an impedance mismatch. Going from 377 ohm, the i.pedance of free space and air down to less than 0.1 ohm is enough to bounce.

[@johnhamms6054]

What does "worst glass thing" mean? What is best glass thing? I seem to have a problem with some of your videos, you start cracking the glass ceiling in my mind, I find myself distracted in contemplating new thoughts and then zone back and have no clue what you just said so i have to watch again... So is that glass ceiling the worst glass thing?? Or is it the best glass thing?

[@kamal2824]

Can u please make the video about Orbitals?

[@ScienceAsylum]

I'll probably will do something more in-depth eventually, but this is the best I can do right now: kzbin.info/www/bejne/qGWTmGCiqteafqs

[@umarshehzad7134]

Why photons, after rejected, move in same direction first moving It can move in any direction after it re-ejected