Michelson Morley Experiment - History of Special Relativity (Part 2)

[@FortheLoveofPhysics]

Special Theory of Relativity ► kzbin.info/www/bejne/iIqsimd3hceJa7M

[@tookurjaerbs]

I really enjoy that you add in the history and stories behind the experiments; it provides a better context. You're a fantastic teacher and I think you were born to do this. :-)

[@caltechharvard]

Wonderful. This is the first time that I followed the Michelson-Morley experiment in great detail. Thank you. So elegant and so simple and yet so profound.

[@mrhasan7867]

kzbin.info/www/bejne/eHTSaHevmtKXqKc

[@FortheLoveofPhysics]

0:59 Ether/Light 4:25 Principle 6:32 Michelson Morley Set up & Calculations 26:25 Results / Conclusions

[@zagor2791]

Perfect explanation of the experiment. Thank you.There is a lot of weak and leak knowledged videos about Michelson-Morley exp but this one very good.

[@harshrana192]

Thanks Sir it is very likely that the history is needed for every concepts but it's not taught in normal courses

[@FortheLoveofPhysics]

+Harsh Rana Yes thats true. A look at the history of STR gives a much better appreciation for the posthulates (which sounds so simple, it underscores the importance of it)

[@manaoharsam4211]

Great experiments brought great discovery. So much respect for their brilliant thinking. I really think if you want to make progress in physics do more experiments. I wish we increase funding for these brilliant people so they can move us to a much better newer generation. The explanation was outstanding. Detailed but very complete .

[@catherinegrimes2308]

This is the best explanation that I have seen and it is a lot better than the explanation in books. Many thanks. शाबाश।

[@adityamkonda4044]

One of the best videos to understand this topic.... Great explanation sir

[@Sigmautub]

Greatest explanation on KZbin ❤

[@ch1ckennuggets481]

underrated channel

[@sidd4190]

Gazab padhate he yaar. Mind blowing sir🙏🙏 Khatarnak style teaching. OP Sir

[@manojitparamanik6146]

In a single word: "RESPECT"! 🙏

[@helifynoe9930]

The theory of Special Relativity(SR), and the Michelson Morley Experiment, when combined, are a blast. The special Relativity theory proves that the idea of movement through an ether can not be excluded. Meanwhile, many people think that SR proves that there is no ether. It is absolutely hilarious. Light is in motion relative to the spatial ether of the absolute 4D structure of Space-Time, and it does so at the speed of light. But this particular magnitude of motion is of no uniqueness. Everything within this space-time 4D ether is also in motion exactly us much as are photons of light in motion. Thus in turn, the direction you travel within space-time is what it is that determines how fast you are moving across space, and how fast you are moving across time. Of course your choice of direction also determines for instance, how much of your spaceship extends across space, and how much of it extends across time, all due to rotation taking place as you have changed your direction of travel. Hence as you pass by others, they will see that your spaceship has shrunk in spatial length, and its once synchronized clocks located at the front and rear of the spaceship, are no longer synchronized, all due to the ship now extending a certain measure across the time dimension. Plus, thanks to your choice of increased spatial motion, and thus decreased motion across the time dimension, observers now also notice that your two clocks are now ticking slower than theirs.

[@AnirudhYadav-vi9ud]

Thank you sir, really enjoyed the whole lecture...... You really remind me of Dr Sheldon Cooper.....

[@nihilisticboi3520]

Perfect! This video cleared a lot of my doubts.

[@thrisha212]

Thursday is my seminar on this topic......thanks for this wonderful session 🤝.

[@fauziarahman3071]

Thank you.. I started taking interest in understanding STR just because of your explanation.

[@madhumitabhowmik4928]

Amazing explanation sir....keep uploading these videos ♡

[@anon795]

SImple and detailed. Helped me very much...thank you so much sir

[@ugursoydan8187]

oh thank you very much. GREAT work. thank you for your labor. thanks for this amazing video!!! 👏👏👏👏

[@venkatreddy6800]

I can't go from here without liking ur video and commenting .u really deserved in teaching physics I really enjoyed the way u teach and never felt boredom ....for the first time myself showed interest in learning physics😊..keep doing more videos 👍👍

[@nickallbritton3796]

We've discussed this in my degree several times, but this video is great! You're a great lecturer. I do have one theoretical question. How would the time difference calculations be different considering Michelson and Morley did not know that the Earth was moving in the direction of the ether or perpendicular to it. So really, there should be a component of velocity in the direction of the ether in both arms of the interferometer, no? I understand that this full calculation would take too long and get in the way of the conceptual points brought up in the video, but does anyone have any resources to help me understand this aspect a little better?

[@Ummesalma-he5xc]

Extremely wonderful 😊 Bundle of thanks sir😊

[@aiswarya4361]

Salute Sir..such a great Explanation 🙏

[@Sigmautub]

Thanks a lot sir ❤

[@Raj_Around_Asia]

Perfect video sir From Bhutan 🇧🇹

[@thinkbetterltd5454]

Very well done! Really enjoyed it

[@joshfranklin9941]

Why do you use the frame of the aether when calculating the time taken by the light to travel the perpendicular path? Why not just stick with the earth's frame?

[@Alkis05]

I can only imagine how confusing or exhilarated they felt when the experiment failed. It must have been very exciting, to see the laws of physics "Breaking down" so noticeably. Specially because the precision of the experiment was way beyond than what was needed. The difference should have being very noticeable.

[@mrhasan7867]

kzbin.info/www/bejne/eHTSaHevmtKXqKc

[@sirajali2475]

Fantastic , thanks for this master piece

[@philoso377]

Nice video and presentation. Remember that Michelson Morley experiment MMX assumes that Aether can drift past matter, atom and molecule freely without interaction or drag, like a ghost wind. And by “no interaction”, light wave propagating in Aether cannot be received or transmitted by or from matter. As a result of the ghost wind, the MMX apparatus can’t emit light at all. Conclusion? Aether is a fluid and moves in equal velocity with matter it attaches and not drift through or around matters. The conclusion also explain why MMX velocity detection is net zero.

[@michaelcweir]

The M/M experiment neglected to test the case for an entrained ether. In other words, the ether interacts with physical objects and the ether is dragged by the presence of the objects. It’s like a stick floating in a river. The velocity of the stick matches the flow of the water, so from that frame of reference, the water appears to be still. So then M/M will only show no relative movement of the ether. There is a modification of M/M that would show the ether is actually moving.

[@ernestschoenmakers8181]

Relative to what?

[@renedekker9806]

_"The M/M experiment neglected to test the case for an entrained ether."_ - other known effects, such as stellar aberration, already ruled out an aether that is dragged by the Earth. The M-M experiment was set up to confirm those other observations.

[@Heaven351]

​@@ernestschoenmakers8181 relative to Ether is neighbouring places of the space being an medium itself as stated by Einstein himself in 1920 lecture " Ether and theory of relativity " in Leiden University . You can read that lecture online

[@leishangthemhero827]

now i understnd clearly wht michelson morley expt is....thnk u sirr....

[@FortheLoveofPhysics]

:)

[@leishangthemhero827]

sir can i have ur whtapp no.. so tht i might have a chnce to ask question when i have doubt....will u give sir.....i m from manipur india

[@FortheLoveofPhysics]

Since this is a public forum, its better not to leave my phone no lying around. U can mail me at [e-mail] and i vl share my details :)

[@kaizokuou8538]

Thank you sir for such a nice explanation 😃👍

[@riyadcy]

L3z khay 🔥🔥🔥🔥🔥🔥🔥🤛

[@pkoukios]

Thank you. Excellent presentation. The rotation is to the left though.

[@swapanmanjhi]

शानदार जबरदस्त 👏

[@akshatpandey9141]

I have subscribed to ur channel it's very good and I understand everything very well thank u so much.

[@RenuSharma-os2mc]

I did many 12 th class topics from u... Now, got admission in HRC Delhi and gotta know that u used to teach here!!! I wish we could have been ur students

[@ebrahimkhansamrat7982]

Just awesome. Thanks a lot sir

[@brotherstech3901]

I came here after watching lecture from H.C.Verma sir on this experiment . I enjoyed both the lectures 😀 Just a slight difference in mathematics 😁

[@venkateswarluborra7891]

very nice presentation

[@ozmoses2011]

The story of this experience is awesome

[@newlife1351]

Acceot my gratitude ❤thanks for such a lecture ❤

[@aparajita_official]

nicely explained.thanks

[@lukesequeiravaz5453]

Thank you so much

[@mrslave41]

26:27 δ=0.37λ (delta is about a third of a wavelength)

[@conceptclassroom.4970]

brilliant and amazing lecture

[@physicsguy-l4h]

Sir ke biceps 💪💪😅😅

[@Drestanto]

At 14:14 Lac' = c*tac Why? Light moves c relative to the ether. So, c+v to the right, c-v to the left. I think it should be c to the bottom Hence, Lac = c*tac (where t2 = tac)

[@Drestanto]

Oh, I just figured it out. I think I wrongly grasped the concept. I got the other way around. So the light need to catch up the earth movement, so it must go at an angle. I get it now

[@akshathnagla4844]

I am Ur one of subscriber

[@footballisgr8]

14:24 how are cc' and ac' are equal when you used pythagoras theorem ?

[@blakeashneet8189]

Hi thanks for your analysis of the Michael Morley experiment. If you assume the earth is not moving around the sun then v is zero . The second conclusion of the experiment ignored by modern scientists, is the earth is not moving around the sun and is still, just as we observe day after day. Narendra New Zealand

[@ReemArshi]

Epic explanation

[@tariqraja2450]

I have a confision. The observer in first case seems to be earth. And in the second case the observer seems to be in ether. This is puzzling. We should calculate wrt to the observer on earth. Plz reply!

[@user-pb4jg2dh4w]

بارك الله فيك

[@spacetime639]

sir please make videos on quantum mechanics

[@physicsismyfiancee...1353]

To be very honest , 1 St time I got most of my doubts cleared

[@KunalkrManna]

Is the fringe pattern is always vertical?

[@mrslave41]

27:59 their experiment failed to prove an aether at 30km/s. but what if the aether was much slower. what if the aether is stationary relative to earth. so only the earth's rotation can be noticed. such an aether would be moving at about 300m/s at Ohio, which is 100 times slower than expected. which makes δ 10,000 times smaller than they expected. so δ=0.37/10000=0.000037. which makes δ just outside Michaelson's setup's precision (0.0005). meaning Michaelson SHOULD have expected a null result. i discussed it here: kzbin.info/www/bejne/m6LJf3SgiZajpdE

[@adityaadhikari597]

sir for virtical motion .....when obsever at earth then he saw a light travel in street line not like triangular thus why we calculate as a triangular ....

[@SupratimBhowmick]

Excellent!!

[@bellousmanibrahim6278]

Do you have a Book writing by you on the videos here 1/40 or a combine PDF..i want to download and read?

[@thisarabandarakuruppuachch262]

Good explain ❤

[@CAL-1442]

Great! Thanks.

[@StefaniaStella-zy1cc]

at 12:55 you explain the trajectory of the light as seen in the ether frame,,,but the composition of velocity is not correctely applied to he vector in the direction AC because this is not the direction of the light in the interferometr frame,,,in this frame flows the ether wind! the composition of this two: velocity in the downward direction and the ether velocity is what you need to add to the speed of the interferometer in order to get the real perspective of what direction is seen in the ether frame according to the galileain laws of velocity composition

[@renedekker9806]

_"because this is not the direction of the light in the interferometr frame"_ - the picture at 12:55 is shown as viewed from the aether frame. The light is supposed to have a constant speed wrt. that frame. That is the speed along the shown diagonal.

[@TarekAbdelmoniem--]

you are great, man

[@yassinbimgdi6124]

thank you so much you really helped me

[@pierattiliodigregorio3064]

I finally understood the historical context and motivations. In many books this part is badly explained....

[@patinthechat6452]

Why are L1 and L2 different lengths specifically? What would happen if they were the same?

[@FortheLoveofPhysics]

Because light wavelength is of the order of few nanometres, it was not possible to make arms L1 and L2 equal to the order of nanometres. Even slightest difference will create a path difference

[@aizazkhan3921]

Love you sir

[@jagdishannepu7179]

Thank you Sir!

[@universky5681]

Sample question :Lorenz factor: K²=1/a²=[1/(1-b)][1/(1+b)] with b=v/c,a=V(1-v²/c²) [V:square] k²=1/2[1/(1-b)+1/(1+b)] 2k=a[1/(1-b)+1/(1+b)] necessarily the multiplication of the mathematical equation by a constancy for example L / c must be respected, that is to say: 2k=2kL/c=a.L/c.[1/(1-b)+1/(1+b)] there is no need of any physical hypothesis to explain this mathematical equation.

[@universky5681]

erratum :2kL/c=a.L/c.[1/(1-b)+1/(1+b)]

[@user-amanfeildconvecture]

Sir can we get notes( happy to getting after pay)?

[@Fatma-d2f6z]

Thank you

[@tripathiadarsh1482]

Awesome!!!

[@WhyShubham967]

thynx a lot sir😃

[@akkupapola]

Thank u sir this video helped me

[@Sumonlaly95]

Sir ,, if we take L1 and L2 both are equal then, will the pattern form...??? How eather is related with shifting of interference pattern...???

[@mecanicaltechnicalworld]

Thank you sir🥰

[@SUBHAM_BOSE]

Sir please will you explain the fringe shift formula. How did you obtain that?

[@pavanajsridhar939]

Sir when I calculate the velocity of the light in the direction of the ether, it's c+v and c-v wrt to the earth. Sir do you think like the second case (in which light is perpendicular), in the first case also the exp set up is moving? If that happens length of light Beam will be more before reflection than after reflection?

[@renedekker9806]

_"If that happens length of light Beam will be more before reflection than after reflection?"_ - that would indeed be an alternative way to calculate the travel time in the direction that is aligned with the aether. The end equation is the same.

[@mrslave41]

24:28 "interference pattern" - what is being shown is the interference pattern of the double slit experiment. this is completely irrelevant. you can search youtube for actual output of a Michaelson interferometer.

[@tusharkumarroy71]

Amazing

[@mohdriyaz9197]

you are great

[@mrslave41]

question: given a boat. it travels from a to b to a. from a to b it travels with the current. from b to a it travels against the current. so you are telling me that the current has an effect on the total travel time a to b to a? how could this be? this defies basic common sense.

[@renedekker9806]

_"how could this be?"_ - see the video for how this could be. But from common sense: the boat spends more time travelling against the current than with the current, and so spends more than half of its travel going slow. Therefore, it's journey will be slower than if there was no current.

[@glennnakamura4831]

I have problems with the explanation of the experiment because you don't take into account that the pond is moving at the same velocity as the car and you don't measure everything relative to the earth which is at rest relative to the pond, car, and wave. This is important because when you do the calculations for the MM experiment, you have everything (device and light wave) moving relative to the ether. When this is done, you find that the speed of the wave when it's moving in the direction of the car is v + u relative to the earth. Also, when the wave is moving in the opposite direction of the car, its speed is v-u relative to the earth. The reason your calculations came out is because in one direction the speed of the wave is v + u and in the other direction the speed is v - u.

[@pawanjoshi2563]

Sir ,you are brlliant

[@faridabatool341]

Thanks sir

[@mahadityasinhsarvaiya3511]

Almost everything explained nicely. Somehow though, couldn't make anything of this velocity figure spoken as three into टेंटीटीपोर eight m/s. Listened to it for about fifteen twenty times. Every time it sounds three into "टेंटीटीपोर" eight m/s. What is that टेंटीटीपोर sir?

[@FortheLoveofPhysics]

Hahaha, 3 x 10^8 m/s ..its the velocity of light

[@nikhilsomvanshi9960]

😂😂😂😂😂

[@danielblanco2556]

thank you

[@satviksingh2940]

I wish u were my professor!

[@user-pb4jg2dh4w]

يعطيك الصحة ، تحيا نتوما

[@akshathnagla4844]

I didn't understand why u took light velocity, c-v in direction of earths movement??? Plzz answer already someone asked u didnt gave answer!

[@mrhasan7867]

kzbin.info/www/bejne/eHTSaHevmtKXqKc

[@SakshiSingh-qo6dc]

Best vedio

[@sovensahoo3103]

Thank you sir

[@technengineeringhub9088]

bravo SIR

[@Angelavhd]

I dont get the reason they rotated it 90 degrees ....please some one explain it to me a bit moreeeee

[@mahesh_gupta1]

Great bro and thanks. But can i ask one things?