Is light a wave or a particle? | Great debates in physics
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- Опубліковано 4 сер 2020
- One of the most famous debates in all of Physics is one that spanned over four centuries and eventually led to Einstein and Bohr debating for most of the 20th century. It was all about the very nature of light - is light a particle (as Newton had insisted) or is light a wave (as people like Young and Maxwell insisted)? It was eventually a problem that quantum physics would solve...
Here's the video I mentioned on the history of light and trying to find the medium it propagates through: • Why can’t anything go ...
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👩🏽💻 Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford.
drbecky.uk.com
rebeccasmethurst.co.uk - Наука та технологія
Thanks to everyone pointing out my mistake in the comments! I incorrectly stated that Young did the double slit experiment with electrons.Young wasn’t the one to do the experiment with electrons - that was Davisson & Germer in 1927 right before the 5th Solvay conference. I think I’ve misread my notes somewhere when I was prepping this video because electrons weren’t even discovered until the end of the 19th century! I seemed to have smushed result in with Young’s experiment in 1801 when I was filming by accident. I don’t really write scripts just make some notes and chat around them, and sometimes this happens! Apologies that neither me or editing Becky spotted that one 🤦🏻♀️
You are a human too, and it's natural to make mistakes. What's more important is to acknowledge the mistakes, which you did✌🏻
While it is the case that _when_ the electron double slit experiment was done is not essential to your narrative, this anachronism is a big error. I don't think you can count on viewers reading your pinned comment. I have to recommend that you re-record the video, and that you replace this version with a corrected video.
Cleon Teunissen Seriously?
Dr. Becky, the difference between you and a politician. you admit your mistakes, correct them, then move forward, rather than sulking and demanding that science changes!
@@nigelm5777 Well, yeah. For comparison, what if in a video by a physicist it is stated that Pluto was discovered by Urbain le Verrier, and that later Neptune was discovered.
So that's why they call themselves particle physicists, but are really wave physicists when no-ones looking?
And to find where you've been will be used cannon ball. Where spot left - there you were. In science this ball called "observer".
Not no-ones, but nobody's, sorry, lol.
A Geneticist can say that we do not know what all of the functions of the so called "Junk DNA" are, but some theoretical physicists will say that their speculations are nearly real without any solid evidence. Many, and I do mean many theoretical physicists with more degrees than I, will call their speculations near to being fact, if not actually factual.
The Universe from quantum fluctuations is a less than satisfying answer. Why will these "scientists" not say they have hit a Planck Wall? Their conjectures are tossed about in the Media because the are counting on their audience's ignorance. The people I am writing about sell books, lots of books, but not science. They became as E. O. Wilson's assessment of Dawkins was as a "journalist". Not a scientist, they gave that up to be celebrities.
Do they have an emotional attachment to their theories? Yes of course. They defend themselves by disparaging philosophy all the while they use it. One said that "Philosophy is dead" a philosophical statement if ever there was one. It contradicts itself. It is a philosophic proclamation, but it cannot be true because it IS philosophy. There is no truth? Is that true? You get the picture? Beware of poor philosophers posing as scientists.
I see what you did there! That's kind of funny.
@@dankuchar6821 It IS funny, but when science is being philosophical it is sad too.
To listen to a physicist ask "what do you mean by truth? during a debate is disheartening. People hear these debates and gravitate to the more charismatic speaker rather than the more truthful speaker.
@@MountainFisher It is part of human's logic. Who is authority. Science schools. Most of scientists doing nothing useful and waiting for 20+ people with brain will solve the problem. Acting as football fans.
My teacher once came up with the analogy of a cylinder: looking from the top it looks like a circle and from the right like a rectangle but actually it is none of both. It just depends on the way you encounter it, how it appears to you.
I like that!
I think we might’ve had the same teacher , same analogy that I have never heard again (until I read yr comment) Lol 😂
That is so well put. My lecturers in physics were always finding ways for us to visualise scientific models. They would have loved that as much as I do.👍
Perspective is a bitch
Jules Phil Exactly. I hate when someone describes it as “sometimes wave, other times particle”. No, it doesn’t change its property, it has both properties all the time.
We could also say it is not particle, neither wave, but it is its own 3rd cathegory, with some similarities to both.
-Is light a wave or a particle?
-Yes
-Yes what?
-Yes, ma'am
My favourite answer to the question "Is light a wave or a particle?" is "Yes.".
And no
de Broglie, Bohm, Bell and others might agree quite literally. It's a bit like asking if a black hole is both a singularity and massive warp in space-time.
@@protocol6 well its actually the same thing. Massive warp of space time is a singularität by definition. Its more like as asking if space and time are the same thing
Mine is "no"
@@protocol6 no, Bell and Bohr disagree with each other on this
I wish I had access to you and your kind of internet teaching(?) 55 years ago when I was 13. Stay safe. -Mike😷
I always get a little 'giddy' when I see that famous picture from Fifth Solvay Conference.
It's often referred as "A picture with highest IQ in history".
If I could go back in time, I'd be happy to push a tea urn around, hand out sandwiches, and just listen in.
I would like to know how that group would respond to "the Universe is a simulation" theory
@@engineeredlifeform i would but i honestly would not understand
The way you can explain experiments and concepts in such a simple and understandable way and at the same time be sooo cientifically precise is amazing! I cannot imagine how hard you work for that, especially being part of Oxford and having the pressure of so many intelligent colleagues watching your videos. Youre an amazing person for making the videos you do! Cheers from Brazil!
Thank you! Very high praise
You sing very well. Make a duo with Sabine Hossenfelder and compose a song "The waves are redshifting in the dus"
French guy here: "de Broglie" is pronounced "de Breuille". And yes, it doesn’t make any sense, even for French people !
So, they were the original "bouquet" family, spelled "Bucket."
for me whole french spelling doesn't make any sense;) sry
Evgeny Kobylyatskiy Je parle français and you are right 🤣😂🤦♂️🤦♂️
the french language was just a practical joke that got out of hand.
Dutch guy here: "Huygens" is pronounced "Huigens", where "ui" is done by pronouncing the sound as it appears in the English word 'man' followed by the Dutch long u.
Looking forward for the next video, this was so intresting... 👏
Amazing video as always, Dr. Becky! Can't wait to see more videos of this series! I would love a video regarding the CPT Symmetry and of course the work of the Dr. Chien-Shiung Wu and Emmy Noether. Thank you for making these phenomenal videos! 😀
Love the bloopers! Please don't stop including them! Thanks. X
I know that I'm months too late for this video but I have just discovered your channel a few days ago. I am enjoying your videos tremendously. When I was in 9th grade, I took an Astrophysics summer camp and one of the topics was particle/wave duality. One of the clearest memories of that time for me is the fascination that the lecture spawned within me and the love for science that grew from that.
Hey, I am loving your content. Your enthusiasm really helps people who don't come from scientific backgrounds to understand your explanations. I would love to see some content on Laniakea and the great attractor if you have not done so already.
Top notch description! Thanks
2:45 I've seen this in physics textbooks a few times but I think this is the first time it's kind of _really_ cliked, wow thanks!
(I actually doubt we never got shown this kind of experiment at school at some point but if we indeed did I guess it wouldn't have been memorable enough)
@12:41 I'm uncertain if that's a picture of Heisenberg, but @12:54 I am sure that Max Born is the grandfather of Olivia Newton John, who sang a lot about physics in her 1981 #1 hit "Let's get Physics all". Einstein visited Born's house for dinner often, but he died in 1955 and Olivia was born in 1957 so they never met, but Olivia literally followed in Albert's footsteps in Max's house.
This post led me to look up ON-J's Wikipedia entry, thinking maybe she was given her middle name after a certain well-known English mathematician of old ... sadly, not true but of course there is a lot of info about her grandfather, Max Born, who won the 1954 Nobel Prize in Physics for his "fundamental research in quantum mechanics, especially in the statistical interpretation of the wave function". There is also an interesting mention of her father, Brinley "Bryn" Newton-John, who worked at Bletchley Park on the Enigma project and so is quite likely to have known Alan Turing ... also, 'Newton-John's father was an MI5 officer ... who took Rudolf Hess into custody during World War II.' All very interesting stuff which was completely unknown to me. Coming from such a stellar scientific background, it was hardly surprising that her first pop music group, formed at the age of 14, should be called the 'Sol Four'. R (Australia)
Great idea for a series. Can't wait for the next one.
Thanks for posting this DrBecky!
This was well-presented and enlightening (no pun intended).
Is Dr Becky a genius, or beautiful?
Why not both!
Depends if you observe or not? I'd say why not both as wel, as well as funny at the very end. Very well explained matter and history. What a photo of those great minds. Coming to think of it....photo made possible by photons.
Genius-beautiful duality
She even ,if not for a breef showed her knie left it is now i'm a happier guy....
Depends on how you look at it ;)
I just discovered your channel lately and I love your way of describing things. As I studied experimental physics myself I am always a feeling a little uneasy when I listen to the WAY the dark whatever discussion is going one - I find it very useful to compare the way this is going with the Aether Theorie discussion. Would be great if you cover that? I already know Sabine Hossenfelders thoughts about it but would really appreciate your PoV too.
Love the way that you explain "stuff" - thanks for your very informative and interesting content!
The out-takes are fun. 🤣
I am so in love with the way she explain things ❤
@Marko no one is talking to you Mr weirdo!
Love your videos, Becky. Thank you.
My suggestion: Is gravity a force or a curvature of space-time?
As I understand it, it's more accurate to think of gravity as a consequence or result of mass existing. Mass itself by existence curves space-time (somehow), and therefore the "force" of gravity exists, even though it's not a force since there's no work being done to make it.
Hi! Idk why but I'm binge watching all of your videos. And I just want to say Thank You!
Always enjoy your posts. I really enjoyed your book as well. Please keep it up, it gives an old man something to think about!
So interesting. Enjoyed sharing this with my 7 year old granddaughter. She even has her own opinion of the nature of light. Thank you so much. From Bakersfield California USA.
I'm curious, what IS her opinion on the nature of light? I've noticed that sometimes children may have an extraordinary insight into things without the contamination of preconceptions or expectations.
@@TheGhostGuitars well she says that if she shakes out a towel she can see tiny specks floating especially where light comes through a window. So she feels that light is particles. Probably not the answer you may expect but she sees the particles and believes they are part of light. Her response to the question " particles or waves" was spontaneously immediate. as her grandmother I enjoyed every bit of the discussion.
@@katherinekinnaird4408 lol, not quite as expected BUT at same time, she's surprisingly close. IMO, I consider the specific points in spacetime on the light wave form is where light can manifest as particles and thus can take on properties of either as required.
Thus her flapping of the towel is the wave form. The dust that's on the towel is the particles.
Nurture that precious intuition, with that intuition she'll grow up to be someone influential in the sciences (or whatever she chooses to be in)!
@@TheGhostGuitars she will be thrilled when i read these to her tomorrow. Thanks so much for taking an interest in the up and coming minds of the future. Good health to you all. From Bakersfield California USA.
@@katherinekinnaird4408 LOL, our future IS in our children! All we can do is try raise them best as we can and leave a decent world for them to live in. I only pray that they do a better job of taking care of this world than some of the people in charge has done!
Lance from Honolulu, Hawaii.
Ohh what is that book in the background, I think I'm gonna go buy it. Marketing successful! :D
I'm going to fly to America and buy one immediately. Just double masking and praying will probably save me from that disease, I heard was going around.
🔅
Wondering the same thing! A stack of books!
Thanks for addressing these arguments. Awesome sauce!
Loved this video. One of your finest.
Solvay, wow talk about being in the room where it happened.
The double slot experiment is the most mind bending thing I have ever seen and then they took it further with the delayed choice thing. If that doest blow your mind you havent got one. Should have explained what happens when you observe each photon though.
A. There are no such things as Photons. Nothing about Light is particle based.
B. Experiment must be correctly interpreted, and to do that, we need ALL the CORRECT information.
C. Half of the information about Light or sub atomic particles does not exist, so we ASSUME stuff.
D. so trying to explain the double slit experiment given a half baked incomplete understanding of most of what were are actually doing, is going to only give nonsense results. Aka, Quantum Mechanics.
This channel always sets me in a great mood! (not to mention the superbe quality of the content itself)
I can't smash enough likes for this video. Great coverage of both the technical and human sides of this progression of ideas and evidence.
I would love to learn more of the LHC, specifically, I cannot wrap my head around the way subatomic particles are detected. How do the quarks interact with normal matter?
Yes this is what gets me excited, would love to get my head around how we measured quarks muons tau electrons higgs boson etc
www.lhc-closer.es/taking_a_closer_look_at_lhc/1.detectors
6:10 Growing up, my dad was a pilot and owned a small plane. I remember taking off and watching the shadow of the plane on the ground. As we climbed higher and higher the shadow would get smaller and more blurry. Finally, just before it vanished, it would turn into a bright spot.
This was especially visible when flying above the clouds. I wondered about that for years and years. How could a shadow become a bright spot? Now I know.
I doubt that is from the Fresnel interference, as sunlight is not monochromatic. What you are seeing is just the Umbra and Penumbra of the plane's shadow. The bright spot may occur when the Umbra disappears and the Penumbra from either side superimpose.
@@RowOfMushyTiT Aren't they the same thing? The bright spot on the middle of the shadow is still there, it's just to small to see from altitude.
Even when the dark shadow is gone, the bright spot is very small.
@@erictaylor5462 Fresnel diffraction is a very different physical phenomenon from the Umbra/Penumbra shadows of aircraft. In fact you need parallel illumination, a point light source, and monochromatic light (aka a laser) to avoid forming a Penumbra in order to do a Fresnel experiment properly. Only under these conditions will you see the bright spot in the center of the Umbra, which represents light waves that diffracted around the object. More likely in the plane shadow you are seeing some low angle reflections or refraction through the windows.
@@RowOfMushyTiT I'm not disagreeing with you outright, but as you have provided only your word, I have no way of knowing if you are right or not.
I don't know anything about you. However, judging from past You Tube comments, I'm taking what you say with a huge grain of salt.
It is nothing against you. I'm sure you would do the same with me. Providing a link to further reading would be helpful here.
@Boodysaspie I know I saw a video on this subject, and I finally found it.
ua-cam.com/video/y9c8oZ49pFc/v-deo.html
Now you can stop arguing with me about something I never even disagreed with you on.
I really liked this video! Well done!
Words are hard, thank you for presenting all of this, I've been binge-watching it and this is a channel I've come to find quite interesting.
HAHA "The universe wept" I have a very difficult time to convince coworkers to pronounce Fresnel zone correctly in RF work. I gave up!
Maybe you should work in the film industry. We have no problem in pronouncing Fresnel.
@@cam35mm ...yeah, Fresnel lenses. I heard the name long before I saw it written. This was with lighthouses.
Someone needs to do a compilation of all of Dr Becky's singing bits - that would be awesome!
Hear hear! +1!
@Bob Wilson I would if I had better PC and internet connection to download and edit those videos.
Working on the PC hardware and software now as I plan to start a UA-cam channel myself.
@@TheGhostGuitars were you successful in making your channel?
@@NZC_Meow Ah no there's a major shortages in some pc hardware right now, especially cpu and vid cards. I'm NOT gonna pay 4-figures for a vid card that debuted for 600-700$. The higher card are going for proportionally higher prices. This is utterly ridiculous!
@@TheGhostGuitars hope you end out making it
The picture at 19:34 - wow. Despite the great Erroneous Electron Experiment Scandal of 2020 this was a fine video. Please do more of these. I so agree, an understanding of the history of a scientific idea is critical in the overall comprehension of the idea itself. Historical perspective of application of the scientific method is vital, and is often makes for a cracking good story!
Nice summary of a great debate presented in a lively manner.
You found a picture of Robert Hooke? Amazing. 😃
There are lots of pictures of him, just not many are contemporary.
Isaac Newton's quote: "If I have seen farther, that is because I have stood on the shoulders of giants." This was a deliberate insult to Robert Hooke, who was small in stature.
@@NeverTalkToCops1 I think Newton took a lot of credit for work he didn't do, and that he was fully aware of it.
I like it, when you go into the history of a scientific debate. It shows in a nutshell the development of an idea and why it was controversial at a time.
And about the Solvay conference: isn't it a shame, that Mrs. Curie was the only women there? As you pointed out in an earlier video, there have been many great female scientists throughout history of science!
There was Lise Meitner
Lovely work Dr. Becky. Yes, both my students and I always find the intersection of light and matter the most interesting and puzzling. Thinking about what it would have been like to be at the 5th Solway conference always makes the back of my neck bristle.
What a great offer from you re asking you to cover a topic. Thank you so much!! Following on from your double slit vid, can you do one on Bell’s Theorem and explain how this shows that the uncertainty in Quantum Mechanics is not caused by our lack of knowledge about hidden variables but is fundamental part of the universe and maybe explain the concept of non-locality as well?
I can hardly wait!
Thank you.
David
Great idea. i've seen a way of looking at Bells theorem with Venn diagrams...
Many years ago (actually decades) I was watching a live program about the crashing of a photo satellite on the moon's surface. I believe it originated in a conference room at Jet Propulsion Laboratory in Pasadena, California, USA. The satellite was sending back digital photos of the moon's surface in real time and the telemetry equipment was displaying the photos on a screen. One member of the panel of scientists was a major proponent of meteorites as the cause of the craters, another member was a major proponent of vulcanism as the source. With the last two or three photos (and one partial) the resolution became better than even the best of earth-based telescopes (marred by atmospheric turbulence). This was even in the face of the poor (by today's standards) resolution of the digital sensor on the satellite. It became clear to all on the panel that the origin of the craters had to be meteorites. --- The program continued with statements by the scientists and the proponent of the vulcan origin admitted he was wrong. His whole reputation had, within a couple of minutes, gone up in smoke. He was upset, disheartened, disappointed. But he retained a respectful level of civility. I was only in my late twenties and had not yet experienced such disappointments in my life/career. But I easily sensed his disappointment so late in his life and remembered the program, so I could relate it to you today.
That must have been the Ranger series of moon probes. I was glued to the TV when those pictures came in. And now--who`d a thunk it?--50 years later, I`ve seen craters on Pluto! I remain stunned as to what basic discoveries have been made in my lifetime, both scientifically and technologically, thanks to rational, smart people--the Dr. Becky`s of the world.
I have an engineering degree, and even through all my physics classes, you explained the whole light particle/wave duality much better than anywhere else. It finally makes sense. Thank you!
The whole point is that it makes no sense. Feynman whose Nobel prize was for QED called it screwy. You just learn the rules (like in a game of chess) and calculate with them.
Interesting video - liked the style - and I was able to stay focused.
What a great video. Very clear discussion of a. Wry unclear topic. Brava!
"Is light a wave or a particle?"
Yes.
Oh sure.... messes up Fresnel but nails Poisson...
All I know is they go down smooth-
wave function
There's something very fishy about his statistics ...
@@I_Don_t_want_a_handle Poisson? Poisson? I LOOOVVEEEEE le Poisson!
It's a Wavicle, obviously.
“There was a cat thrown amongst the pigeons” ... is the cat alive or dead or both ?
Depends how hungry the pigeons are.
Schrödinger: Yes.
@@KABNeenan Well... It was his cat after all...
It simply is in superposition; it's both AND none :-). Ow, and if it's MY cat I can tell you the pigeon's wave-function WILL collapse and surely they'll be dead :P
It depends on how far the cat was thrown from (and how many lives it has reamaining).
That was a brilliantly easy to understand quantum sum up Becky, fascinating!
Nicely explained!
Is light a wave or a particle?
That depends on how you look at it.
If you look at it?
"Imagine the reaction of the world if someone claims Einstein was wrong about something". Procedes to tell us how Einstein was wrong about something.
Imagine the reaction of the world when someone proved that Einstein was wrong about something then someone else proved that he actually was right.
He's been found wrong on some minor points - coolworlds astronomer David Kipping stumbled onto a mathematical faux pas in an Einstein paper. Einstein was wrong about the dice thing. He was wrong about entanglement. He was wrong about lambda not once but twice! Stop treating him as infallible!
@@alleneverhart4141 the key is to be right or wrong about the right things. he clearly had a knack for finding important problems to solve
Imagine calling the cosmological constant your greatest mistake and then someone who's puzzled by dark energy digs up your mistake and decides it probably wasn't a mistake at all. Can't even make proper mistakes like regular people :(
Congratulations Becky, very intereting video about one of the most facinating physics dilema. I work designing and manufacturing light managament films and shade cloths for the greenhouse industry, and this physics dilema keeps me pushing to try to get a better undestanding of light.
Wonderful video Dr.
SO... light is a particle, that is waving frantically at us.... :~) a "warticle" of sorts...
Wavticle, pave, parvle...
I like wavicle or partave.
@@msclrhd I second "wavicle"
Since light is passing by its waves, ( hheeeeyy) , does that mean its a cross-dresser? :) lol
So, it vacillates as well as oscillate? Is it that indecisive?
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Oh no! We are an old retired couple and the only way we know what day it is is when your video comes out...now we will always be off a day...sighhhhhh
I really enjoyed this video, I learned a lot. Thanks Dr. Becky :)
That was amazing... great explanation.
Einstein: God does not play dice.
Wolfgang Pauli: Einstein, stop telling god what to do.
Actually that was Niels Bohr that told Einstein that
The universe plays god and the universe plays dice.
This video and comment section are full of mistakes.
My favourite fringe theory on this:
1. What we call light is actually a combination of a particle and a wave.
2. Both the wave and the particle have an independent existence. Particles don't become waves or vice versa.
3. A particle moves if and only if it encounters a wave. It's a guiding wave or "pilot wave" if you will.
4. Waves can travel along the direction of the particle's path (e.g. Both particle and wave go left to right), or exactly opposite to the particle's path (wave goes left, particle goes right). There's evidence for both.
Keep up the great work Dr. Becky. Love these videos. Best wishes.
I really appreciate they way you boil these videos down to a level that makes it easier for those of us who are not physicists to understand.
Light has dissociative identity disorder at its most fundamental level.
Just like everything else ... me, you and they ...
It’s an electromagnetic Bose-Einstein condensate.
Am I doing it or ist it myself ?
It's manic, depressive, manic, depressive...
It's electro, magnetic, electro, magnetic...
How about "It's a particle waving at you!"
Split personality? Schizophrenia? You think it is also paranoid? Maybe it listened to atoms and got rudely disillusioned when it found out that atoms make up everything!
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Can you imagine being there when they took that photo?! The who's who of the greatest minds the world has ever seen!
Always enjoy your vids. :-)
Meh .... they weren’t that smart ... it was easier for them because nobody knew nothing back them ...
I really enjoyed this one Dr. Becky, faux pas and all! And, my book arrived this week, complete with your signature that I watched you write! i was hoping for one with the Galaxy but I'm happy anyway.
So each week I'm wandering along in life then BAM! Suddenly, I'm immersed in physics! And yet, Dr. Becky explains a really, really difficult subject better than most. I am always pleased to watch your videos, Doctor. May you live a thousand years and enjoy every day of it all.
Poisson must have been a bit of a wet fish at parties.
Sorry, but I just had to - I'll see myself out. :-P
Yes and Einstein must have looked like a rock.
Physicist: Is light a wave or a particle?
Programmer of The Matrix: Yes!
Absolutely brilliant..
So perfectly done.. Bravo!!!
Very good video covering a lot of non-trivial concepts. Keep up the good work Dr Becky! BTW, my suggestion for the debate series would be how contemporary Bell's inequality experiments have tilted the scales towards instantaneous action at a distance.
Your video got me delving into the Photoelectric effect. The Photoelectric effect, Hertz 1887, is that polished metal plates irradiated with light may emit photoelectrons. A threshold frequency "fo" was seen to exist at which only for f>fo will we see a current, this was not explained classically. Another result was that the magnitude of the current depends on the intensity of the light. The interesting result was that the energy of the emitted electron depended on the frequency of the irradiating light.
E = hf - W was conjectured to explain the result, where h = Planck's constant, W = work function to expel the electron, and E is the energy of the electron (Einstein 1905). Millikan in 1915 empirically verified this expression that Einstein conjectured. He measured h, Planck's constant, to 1% accuracy apparently.
Again, your videos are critical in explaining quite difficult concepts to your audience. Keep up the good work!
...guilty: as a german i love to see a native english speaker struggling with the right pronunciation and words!
@Peter Mortensen ja i did it kinda on purpose...
Sweet video! Very informative for a topic I've heard of but didn't know a lot about. I've Only ever really of light being seen as a wave or a particle but nothing more specific or helpful than that :D
really good explaining of this topic and I love the history side of it
Had to watch it twice to grasp it but I really enjoyed this video:D 10/10
just brilliantly clear articulation (as always) of a complex, confusing subject - love the out-takes :)
your videos are awesome, thank you !
Fantastic video
Thanks for sharing👍😀
Just found your channel. Watched this video. Subscribed. You're explanation is so easy to understand and so fun to watch. I love quantum mechanics, and physics, but I've always found this topic so confusing. Thank you so much. When I grow up, I'd like to get a degree in physics so that I can apply quantum mechanics and relativity to find a new space propulsion method; I also love rockets. Just a question: How does an electron/photon know when it's being observed? How does a wave know when to transform into a particle?
Excellent talk. I find the history of the sciences fascinating.
Can you do the AMPS paradox debate, the whole ER = EPR situation, and aDS/cft correspondence? I'm very much a novice but, it's interesting! Also, these videos are great! Thank you for making them!
This video helped me get a couple of pronunciations and facts correct. Thanks!
Hello @dr Becky, I loved this video. Thanks for making such wonderful videos. I have a doubt why do black holes have accretion disk not accretion sphere? Waiting for your reply. 😄
Dr.Becky I hope I state this correctly. I would like to see a great debate symmetry vs asymmetry when talking about the big bang and particle annihilation . BTW im an ignorant peasant when comes to physics but I find this topic very interesting and you make it so much fun. -Thanks Blake
Very informative video thank you
Thanks, excellent lecture.
Thank you so much for making this video. I have been looking for something that explained the photon side of things. The wave makes so much sense to me. This is perfect and makes sense given this history behind where we are today. Thank you again!
I didn't know about the disc and the shadow experiment. Thanks for allowing me to learn something today.
Thanks for this lecture Becky! This is my question; what about gravity? What is its carrier? Wave? Energy?
I have only just seen this video (I haven't been watching this channel all that long and am now getting through the vast catalogue of past videos). This is the first time an explanation of wave-particle duality has truly made sense to me and how light (and electrons etc) are waves until you try to measure them in some way and "force" them to act like a particle. I dunno, its a bit like the difference between a wave on a body of water and a molecule of water. Well anyway, its the first time I've been able to really visualise it, and I watch PBS Spacetime. Thank you Dr. Becky!
The problem is that there simply is no wave-particle duality. That's just an old false dichotomy fallacy that won't go away. Quanta of energy can behave in many, many different ways. To quote Alan Adams of MIT (he has an excellent QM 101 course on UA-cam): "Many electrons don't behave like waves. They behave like cheese.". The wave-particle duality fallacy is about as "scientific" as the four humors theory in medicine at this point. It's just a pity that even many physicists can't let go of it.
you simply deserve millions of subscribers, thanks for your great work, greetings from Argentina.
Dear Dr Becky. You are the #1 physics and cosmology "explainers" to people with limited physics backgrounds. Your enthusiasm is contagious. Thanks! Keep it up!
You are inspiration to many.
Btw your videos are Fantastic.
A great continuation for this great video would be De Broglie-Bohm's Pilot Wave and Bohmian Mechanics, why it is not well accepted and what it's non-locality means. Please Becky, please!!!
Dr Becky you are awesome! this is one of the topics I struggle comprehending