Where Does Light Come From? (Electrodynamics)
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- Опубліковано 25 лип 2024
- It's often said that light is an electromagnetic wave, a disturbance in electric and magnetic fields, but what does that mean? How are they made? Let's take a deeper look at electrodynamics and this history behind the discovery to see if we can find an answer.
Also, thanks to Science With Steph for lending her Scottish boyfriend's voice:
/ sciencewithsteph
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VIDEO ANNOTATIONS/CARDS
Electrodynamics Playlist:
• Electricity and Magnetism
Turning Magnetism Into Electricity:
• Turning Magnetism Into...
How Fast Is Light?
• How Fast Is Light?
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LINKS TO COMMENTS
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IMAGE CREDITS
Andre-Marie Ampere:
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Carl Friedrich Gauss:
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Michael Faraday:
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James Clerk Maxwell:
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Oliver Heaviside:
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Big Bang:
• NASA | The Big Bang
Thanks to *Science With Steph* for lending her Scottish boyfriend's voice: ua-cam.com/users/sciencewithsteph
And now tell us something about dielectric constants and permittivity. ;)
I thought that you will speak about the image of black hole. However crazy job 🤘🤙
Thanks, nick!
@@SciencewithSteph You're very welcome!
Can you do a video on what happens when light is reflected? Like what happens at the atomic level re angle of incidence/reflection...
I am kinda addicted to light. It's like I can't even see without it.
I dont like your joke. It made me angry and I feel like pooping on a plate and eating it.
So you are not a bat.
@@a.m.1298 Stop it, get some help.
*....I can’t see very when I have a blindfold on either....*
@@a.m.1298 wth man
I have an engineering background, and have tutored students in EM physics countless times. But this is the first time light as a disturbance in the EM field ever made intuitive sense to me. Thank you!
No wonder students are confused.
How do you not know this ted you are a teacher! 🤣
Your explanations are very a step further than anywhere else, you just give the right thing that makes it very clear!
But it's still doesn't help me, because I can't retain information unless I hear it on a regular basis.
@@yourallbrainwashed Stay interested! Keep watching his videos in order and he will reemphasize previous points. Builds foundational knowledge, reinforces it, and applies it to new information.
I could not disagree more. For example, he still has not answered where light comes from. Also, a very few of the electromagnetic waves are called "light". The vast majority cannot be seen by human eyes, such as gamma rays, x-rays, ultra-violet (UV radiation), infrared (IR radiation), microwave, and radio waves.
@@danweaver4304 what we see is "visible" light. Everything on the spectrum is light, gamma to radio
@@danweaver4304 Replying very late to this. But why 'light' or rather electromagnetic waves behaves like this or originates from is explained by quantum electrodynamics. Classical theory only goes this far.
You make a big difference in many people's lives. Not just enjoyment, not just education, but an actual difference. Well done. And thank you.
I can´t believe that you made this entire video without once mentioning photons
Indeed. Did I miss an episode, or will this be the topic of the next one?
Photons are just one model for light. Electromagnetic waves are a different model. Talking about photons would have distracted from my point. Photons are a _whole_ other video.
@@ScienceAsylum thank you so very much for the clarification. I just thought you would at least have one of the clones mention photons or something like that. Anyway, big fan, looking forward to the next video
So if one model doesn't require photons, but the other does, then which one is reality? I think that neither is actual reality but the math works so.... So much to learn.
@@FASTFASTmusic - light has properties of both waves (electromagnetism described) and particles (aka photons).
The last 30 seconds of this video literally blew my mind. I've never had anyone describe fields as well as you did. I need a moment...I need to go pick up my brain now
Same thing happened to me
YES!!!!
Thats exactly what i felt.
Just recovered, and checked this comment, which means few more brain got the dead Lock too.
Same here. Put a tear in my eye actually., like "Wow, I just not only learned something but I learned something that fundamentally changes my interpretation of the physical world.
This is probably the best video on light that I've seen! The last few minutes we mind blowing. My take away is that light's electromagnetic field (at least in the case of the antenna) is a signal telling you what some charges were doing in the past.
This video is eye opening, illuminating, enlightening, elucidating! Puns intended!
I'm having a difficult time putting into words how this video changed my perception and understanding of the fundamental principles of electromagnetic radiation. It's like I'd been struggling at a jigsaw puzzle, I've got the box so I know what the big picture looks like and I know I've got all the pieces but I can't get it to come together. Then you come along and say"It'd be a lot easier if you put the pieces on a table instead of trying to hang them out in midair". Thank you, I feel like I've leveled up.
I don't think you'll see this but I ain't losing anything I guess
I used to watch your content religiously back when you were a small channel (you have grown so much recently, damn, congratulations). You're part (most) of the reason why I decided to pursue astrophysics as a career and I'm not pretty into it. Because of this, I haven't been watching as much astronomy stuff as I used to on UA-cam (most of it is more general content I've already seen in class via excruciating math) but seeing this on my feed made me go, 'Oh, why not?'
What I really want to say is that I've learned more from you in six minutes than it takes me to learn the same topic at college in six months. I'd forgotten just how great this channel is at explaining. Thank you :D
That's wonderful to hear! I'm happy that I've had an impact on you and I'm sorry you're having a hard time in college. It can get really difficult, especially if the teacher isn't great. You just have to decide if it's worth it.
literally anything is worth it if my favorite content creator on youtube replies to my comment
It has been hard, yes, but so are all the good thinks. Thank you so much for replying! This just motivated me like nothing else could. Thank you so much AHHH
@@maf7742 if your having trouble understanding a concept (be it physics or anything else) try looking it up on UA-cam or Google. It's amazing how a good teacher can make a complex concept seem simple and easy to understand where a bad teacher will make you feel like your bashing your head against a brick wall.
It's such a pity all these resources weren't available back when l was in school/uni it would have made things so much easier to understand when the books and lecturers weren't getting the ideas across well.
to deeply understand this kinda shit, you really need to see/hear A LOT o diferente point of view, just with you college teacher and your face deep on book isn't enough, never understimate a youtube vídeo on a realative basic stuff (not those crap conspirasy or click bait ones of course) you still can learn even though you already now.
and TSA is the best on this cuz, if you already now the topic in question, you dig so much information of it in litteraly a cupple of minutes, that is like relearning every thing again.
@@Jake12220 yeah I think the teachers that make subjects difficult are the ones who don't really grasp it too deeply themselves because it seems that explaining something on flawed premises makes it more complicated. Also some UA-cam videos that simplify are wrong too like the professor that uses a trampoline to model gravity = 54 million views and I fell for that even shared it, until found the better explanation of gravity by The Science Asylum
Damn Nick, you should get a reward for making these videos! Being able to explain something as difficult as this so that even I can understand has to be some kind of record! Thank you!
Damn, I'm having some difficulties understanding it, you're making me feel dumb
Wow! This clarified light so much, of why it's called an EM wave. Also, funnily enough I was thinking "I don't understand physics well. For example, how's light an EM disturbance". This was so timely. UA-cam recommendation was spot on this time
This is insanely clear. The best part of the explaination is that it sticked to itself from the start as best it could, having very little stretching to the far out of the topic (as most science videos tends to be in order to be accurate).
One the best example videos of ELI5 kind of things. I am saving this for future refrence 😁👍
Haha, "he saw the light, like literally, he rediscovered light" 😄.
You rediscovered the visualisation of an electromagnetic wave (pattern) here. Wow!
Yeah, I'm really proud of that animation. It's what inspired this video.
@@ScienceAsylum I was able to grasp the whole concept finally. Thank you Nick! You wrote a great book btw!
I thought God discovered Light first?
@@kevinpatty119 nope..he created it.
I think that is my favorite Electro-magnetic Field/ Light video explanation ever!
Great work!
Yeah, this is definitely a great one!
Way to go, Nick!
Fred
As a radio ham, I found the radio analogy very helpful and indeed reaffirmed my loose and sketchy idea of how (radio) waves propagate. Love the energy, humour and truths in your videos! 73, de M0NJX
Ive seen two videos so far, subbed four minutes into this. This content is remarkable, and I want to thank you.
Welcome! :-)
"I sense a disturbance in the force... field."
From which manga your profile pic is from
pravin rao Negima!
I love Negima!
now i could say that i'm enLIGHTened. thanks for the great video❤❤😍
Eye opener. Changed the way I see light. I am not new to electro magnetic theory but the visualisations never happened until I saw this video
Like always, your way to explain complex stuff to make it easily comprehensible is brilliant. Thanks for another lucid video!
Any day with a new Science Asylum video is a good day.
I wish we had teachers like you who make things so intuitive. Great work!!
Thanks!
One of the best explanation on youtube. Speed of light is how much time it takes a field disturbance to have an effect between a spacetime interval. So the speed of light is the speed of causality, right?
Exactly!
Fantastic video! I appreciate how well you explain the concept, but how you incorporated the history as well.
The bit with the antenna...moving charge causes fluctuations in the field then plug in the delay and you get waves!!! I've never seen this explained before. I've seen the light! Thank you Nick.
Hi Tony, good spot - that is the crux of the matter. The follow on question is to ask how come the energy of that wave is barely attenuated as light propagates through free space seemingly forever.
Could you please make a video on the electromagnetic spectrum? I've heard it mentioned in a bunch of videos, but doesn't have one for itself. Your videos make much more sense than any other lecture!
This is the best AND most concise description of the subject I have ever seen. Shows you deeply understand these things.
This is awesome! Totally helped me better understand some basic ham radio antenna theory better. Thank you!
Explanation quality is super! Keep it up bro...
I agree wholeheartedly!
I have seen the light! I have been a fan of yours for a while now and love how you take graduate level ideas and make them elementary. I think I can safely say: you took one of the most beautiful and complex ideas, and reduced it to something simple. The beauty was enhanced! You may not have discovered these ideas, but you have given them to the masses. Keep up this amazing work!
Nick, I thought I was OK with physics before I started watching your channel. I've learned so much more since then. You have an amazing ability to make the complex seem simple. Rock on!
Thanks! 🤓
Another Fantastic Video Nick.
As usual Explanation quality amazing.
Your face when you say "back to the Timeline" 😂😂
I'm so happy I subscribed to this channel earlier.
This is the explanation of radio waves I've been waiting for all my life. Thank you.
You're welcome :-)
Wow, you described to me in 6 min. what my lecturer wasn't capable of to do in 6 Weeks.
you're awesome!
This is one of your more convincing explanations so far. Thank you so much!
OH MY FRIG I absolutely love this explanation! I heard this already before in a book, but it wasn't nearly so easy to understand
Nick, you have the most understandable, most informative, enjoyable and genuinely FUNNY shows in all science. Thank you for the science enlightenment!
Thanks!
You have the best field animations of any channel. This video was awesome!
My Monday is successful 😁 amazing connections! You're a true educator Nick!
Wow; these videos deserve to be in every physics/electrical engineering course around the world. Been working in the electric utility industry for several years now; and despite my education these videos have done soooooooo so much to expand my intuition. I subscribe to a lot of engineering and science channels but by far your channel is the easiest to digest!
changing electric field (AC) inducing a changing magnetic field, creating another changing electric field across a gap to a nearby coil. You described a TRANSFORMER.
You present your material with incredible clarity.
These videos are so detailed. It takes many times watching to grasp the content in its entirety. Content is coherent and follows the correct order but to realise that it takes multiple viewings. But each viewing gives more satisfaction than the one before. Awesome work bro. Thankyou.
On a fun note.. nick’s 100k views could be just 20k people watching the video 5 times.
Oh my FREAKING GOD. I'm speachless. The last minute of this video was 10 times more mindblowing than a whole uni semester of phisics (and I already passed my exam)
This is a wonderful explanation. Thank you.
Thank you so much for clarifying this topic.
The radio tower analogy finally made it click for me
Glad it helped!
I knew that light was electromagnetic waves and I knew that electric fields affect magnetic fields and vice versa, but for some reason the connection was never made that that is exactly WHY light waves occur in the first place! Every one of your videos manages to open my eyes to something new every time.
Watched it again, wow.. Mind blowing, so the universe is a field. Everything is a field, and we manipulate that field..
Another entertains way of giving us another way of looking at electromagnetism. Thanks!
That explanation with the radio tower and how the field arrows stay in place is the best I've seen for this subject. I feel like I understand it much better now.
i was really puzzled about EM waves for a couple of days and had spent hours seeing videos about but this one just proved to be a eureka moment
Glad I could help 🤓
Where's my heart? Excellent video, will be sharing with my family. Kudos for mentioning Heaviside. And yes, I have seen the light!
It's 12 AM in India,but when I saw a upload from science asylum just started watching it without sleeping.
space is where we belong to! Me too
Your videos are very good at explaining things. I recently watched a video of Feynman talking about perceiving light and he compared it to an insect interpreting the waves in a pool to get a picture of where every moving thing was in the pool, then said that with light it is the same thing because it's just waves in the electromagnetic field. Your video was a great follow-up to that.
Excellent video Nick. Possibly one of the best tutorial videos in physics ever made.
Dude I love watching your videos, for one, you help me grasp and comprehend the material (age31); as well as my kids (ages11,9,8,6) can grasp and better understand the subjects because you make it interesting, fun, and exciting! Thank you for putting in the time and effort to make these videos!
I love to hear about viewers sharing with their kids 🙂
Been a physics fan all my life, this was the most intuitive explanation I've ever heard/seen. If anyone can point me to a better one, please comment.
this guy fills in holes in ur physics road, that some of them, u never even knew existed. im not that smart, but sometimes these physics explanations seem to be missing pieces, and then i see this guy's vids, and realize, yeah, they were overly simplistic .
This channel is very very very very very great... He also replies our comment questions.... But other channels don't do that.. Thank u sir
You're welcome 👍
these models are incredible at explaining how waves work, I finally understand the nature of electromagnetism (and didn't even have to learn math!)
Brilliantly explained 🙂👍
Yes! My surprise Monday off just got better with a surprise SA video!
Thank you for doing a series on electrodynamics!! You have facilitated my knowledge on this phenomena, and, for that, I am eternally thankful! Cheers!
I've been watching quantum physics and science videos on UA-cam for years and this one is second in awesomeness only to the first time I found out about the double slit experiment. Thanks.
Another great video! I'd just like to give a shout out to the graphics you use. They're clear, rather than fancy. Fancy graphics can be distracting, so I think you've struck a good balance there.
Thanks!
I never thought about that. this actually explains why the bosons which mediate electro magnetic force are called photons
Just love the way you narrate scientific concepts to make it fun to follow and understand. Thanks.
This is the most under rated channel on UA-cam!
I don't know what this guy is talking about, but I like his videos!
Sir, your candor is refreshing.
30 years struggling to understand what all that nonsense about fields even means, and this guy steps up and clears it right the hell up in under 7 minutes. I feel like I just took a shotgun blast full of knowledge directly to the head
Best metaphor ever. Also apt.
I was looking for so long to understand this. Thank you.
Nick Lucid you are a real SUPERSTAR! Thank you for cutting through the "red tape" and explaining things so clearly. Why can't all teachers be like you? Thank you so much.
Thanks!! This has helped me figure out a lot of things! :D
@@cherifaly6757 1. How light can move forever at the speed of light without any energy input!
2. How light gets transmitted in space because when I searched it up is said that light was a longitudinal wave instead of transverse waves which confused me.
And 3. How electric and magnetic charges and waves correlate!
@@cherifaly6757 Oh, also how energy field fluxes can affect other fields!
@@cherifaly6757 For example, how come light is part of the electromagnetic spectrum. I couldn't grasp the meaning of that. I heard it very often but never knew how to properly ask about how they were related. This video helped clear a lot of questions.
If you keep up creating such great videos you are going to make your life very stressful as people's expectations begin to crush you... but personally, I hope you are able to keep this up.
_"You are going to make your life very stressful as people's expectations begin to crush you."_ ....already happening but it hasn't stopped me yet.
every piece of content you produce is a home run!
Thanks! (I don't agree, but I appreciate the encouragement.)
I noticed the delay of light when I was little. When I flipped the switch and the light didn't instantly turn on. Then I realized it takes a few seconds for the light to travel to it's destination. I'm loving the channel. Some parts blow my mind for a moment and some confuse me for a second but it all works itself out within a few seconds especially with your explanations and demonstrations. It's hard to confuse me and not much blows my mind. But I do enjoy the feeling because I can feel my mind expanding and it's been a long time since I really felt I learned something big and new. I felt like my mind was stagnating and that's not good. Recently with your channel and a few others I've found myself really enjoying my UA-cam experience. There are so many channels that would even make dirt stupid and it saddens me that people actually find it entertaining. Not everything I watch teaches me but it also doesn't dumb me down. Sorry for the rant I love the channel just had to put that out there.
What i can say about this channel? Is amazing, wtf
This is great, I love it when you do these type of time lines. (you should do more of them)
Best, most intuitive and concise description of light I have come across in a while. Love the channel.
Thanks! 🤓
This is by far the greatest explanatiin ever of the complex mathematical formalism associated with the physics of electromagnetic waves.The presentation at the end of the video is simply amazing...particularly the field and wave propagation through e/m field
This made me wonder if we made a small enough antenna (~300nm) could we produce optical light using a dipole antenna...
When I googled, I discovered there is ongoing research into this very thing!
yes, it is the field of meta material, and you can do a lot of cool shit
how ? pls give me some insights , i am curious about it!
Man, what a brilliant video. I was able to understand in five minutes (and after a few repetitions) what I struggled to grasp from my physics teacher in that soporific classroom environment back in high school. Though there was that gorgeous blonde I had a crush on sitting in front of me. Talk about disturbance in the field.
There are things that I never thought I would understand until I discovered this channel.
Super well done video. Especially the graphics of the fields. I'm impressed
I still don't understand how light can travel in straight lines if waves always scatter in a circular fashion.
Because light is not a wave - it's a particle with probability distribution. In classical electrodynamics, the Maxwell model is perfectly fine. It utterly breaks if you achieve quantum effects, like the photoelectric effect. Energy is not continuous across space anymore - it's quantized.
We've also seen this in the famous Young Double Slit experiment when it was performed with individual electrons or photons. The particle's behave probabilistically.
@@FabrisFanatic it seems really unintuitive actually. it seems like there's no physical analogy for those quantum stuff, one thing that bothers me about this is why don't the light interfere with itself everywhere and instead of doing it only on the double slit and if it does, why don't we see interference patterns everywhere.
@@Jeacom Interference happens every time the magnetic and electric fields of two electromagnetic waves "touch" each other (they combine into a new field. The new field is the vector sum of the two original fields). So every time two signals are going through each other, it is called interference.
Think of a rock being dropped into a pool of water. The waves radiate out from the centre. Now imagine that a tiny surfer is surfing one of the waves. He will move out from the centre in a straight line. Similarly, a light bulb radiates light out in all directions. But individual photons each follow their own path radiating outwards from the centre like the spokes of a bicycle wheel.
As for explanations of the wave / particle duality, quantum effects and so forth, I'll leave that to the experts!
Oh, and as a wee aside it is worth mentioning that Albert Einstein was a big fan of Maxwell (even if his equations needed polishing). Though to be honest I may just be mentioning this because I am a little biased in Maxwell's favour. I had the pleasure of visiting the residence that was his birthplace and is now a museum a number of years back (during the Edinburgh Science Festival). We were treated to a talk on his life and achievements.
It is a shame that he is not revered more. Even in his country of birth, few other than those with an interest in physics know about him and yet his Wikipedia entry has besides the entry for "Influenced:" the words "Virtually all subsequent physics". Indeed, were it not for Maxwell I might very well not have had this device to tap my thoughts into or a means by which to communicate them to just about any inhabited part of the planet. That's quite a thought!
We need to know more about HEAVISIDE it's look like he was so unapreatiated and treated unfearly by histoty.. How is with me? More "likes" to convince NICK to make vedio about HEAVISIDE
Excellent, best description of maxwells laws I have ever heard, and to point out Heavysides contribution to the simplification of the of the math is a breath of fresh air.
That was AMAZINGLY AMAZING. That delay between reactions bit was fantastic and revealing to me.
I feel a disturbance in the field. OMG I can see it!!
I could not help but wonder what Carl Friedrich Gauss would have thought of your silly videos.
He probably would have loved them ;)
Thank you for pumping out these cool videos (: we appreciate you
Excellent video - it really helped me tie a couple loose ends on concepts I’ve wanted to better understand! I’m glad I stumbled across you channel a while back, and I’ll keep spreading the word because you deserve way more subscribers. 👍
Thanks!
Ahhhhhhhhh that makes sense for waves..... So where do the photons come from??!
I think there's still a few fundamental truths that we have yet to uncover to really give a satisfying answer to the average joe.
All we can really do is predict a bunch of stuff and sometimes we get better results if we use the photon model and sometimes it's better to use the waves model.
We know they're both true tho and that light carries momentum and is affected by gravity yet still behaves like a wave and has no mass.....
It is due to the fact that light can be a wave or a particle so there are two models for the propagation of light.
@@oremooremo5075 yes I get that, so how do you reconcile the two models? Electrons can emit photons no problem so are there virtual electrons in these electromagnetic fields?
JamesMulvale You can't that's how weird nature is at the fundamental level. Matter is either a wave or a particle depending on how you observe it.
JamesMulvale I think there are supposed to be fields for every particle woven into the universe itself.
So every time I switch on the lamp of my room I turn on a field disturbing machine. It is Great to be Crazy.
Indeed!
I just love to watch , picking it up too, your teaching is funtastick, thanks 😊
Great video and answers a lot of my questions.
Game of Thrones in a while and this. Monday is turning out ok
GoT came out yesterday though
JumPInfectioN Not in the U.K. 2am and repeated at 9pm.
They _really_ need to start releasing things everywhere at the same time.
@@ScienceAsylum for real, especially since most of the actors in GoT are from the UK
@@ScienceAsylum If you can demonstrate a working model of the physics behind the seasons in Game of Thrones, I'll give a paycheck to patreon
As an EE, I appreciate this video.
Thank you Nick. Just don't stop posting the good stuff.
The last part of the video is really one of the best visual metaphors I have ever seen which provided a detailed real illustration of the propagation of EM radiation through space. I am still struggling to familiarise with this as though I understand changing B produces changing E and so on... But the visualization is damn good! Thank you very much Nick, no one ever has made such great video with great visualization. Prior to this I asked myself, is wave 1-D? Because in textbooks and youtube I see the "default" wave diagram which describes like λ, υ etc. Since, physics is not my undergrad subject (chemistry is) so when such stuff appear in Spectroscopy I asked myself that since (though it may appear vague) that atoms are 3-D, then waves should have to be 3-D to travel in 3-D space... But how to visualise this have been bothering for years until I saw this video. Still, it's hard for me to familiarise (lol)
PS: I like how your question clone asks the same question that come in viewers' minds (incl me)