@@f.falkwings well, it's this setup deep under ground and spread over a kilometer but yeah it's basically the same setup The trick is the bigger you make it the more sensitive it is, the one at LIGO can measure differences smaller then the width of a proton
Hello Action Lab!! Whenever you post a new video, it will be around 10:00 PM in INDIA and after having dinner it gives a lot of satisfaction to watch your science experiments. Thanks a lot and LOVE FROM INDIA♥️♥️
There's a type of little kiosk in stores where if you stand in/under them virtually all exterior sound vanishes. Also, sound from speakers in the kiosk did not travel outside of it.
Really cool aspect to this experiment; you talked about how doing something as simple as walking on the floor can change the phase between two light sources but temperature differences actually do the same thing so if you breathed over one light source you could actually see a phase difference.
I knew about how noise cancelation works with offsetting sound waves by 180 degrees. But I wondered if light cancelation was possible. Whe I thought about it I realized how hard it would be but am very happy now to see it explained in a video. Thank you!
@@AttilaAsztalos I was thinking more of a military base/nuclear plant type perimeter seismic defense system. I'm pretty sure a physicist could triangulate the exact coordinates of the slightest movements, based on variations in the interference patterns, then pass that data off to a programmer's software, which would automate the relevant security cameras to investigate, and deploy armed drones to intercept a minor threat, or send alerts human security personnel, if more lethal countermeasures are necessary to neutralize a major threat. This would be way too sensitive for normal civilian use. Every step in the home, speaker bass drop, kitchen appliance, car that passes by, etc., would set off a false positive.
@@Fermion.Wow, this has gotta be a personal best at thread necromancy... ;) Anyway, LIGO detects gravitational waves with the same basic setup and it's just HILARIOUS to read up on what they need to go through to eliminate vibrations caused by, well, everything else...
@@AttilaAsztalos Ahh, you're right about LIGO. I totally forgot about that. But, the thing about that is that it would be super expensive, with the miles and miles of vacuum-sealed tunnels, and several teams of world class scientists. And yeah, I made several edits after a few drinks lol.
This video is exactly the reason why i got to know your channel. I had this doubt for a long time and when i searched it in youtube, i got your other videos on additive mixing, subtractive mixing and those on 'if black and white are colours'. Now my doubt is finally cleared. But i can't stop following your channel as your experiments are on the next level. Thanks a lot. It is actually surprising to know that you came to this height from crushing a golf ball on hydraulic press.
Wow. This channel has put science into so many of my twin brother and my comic characters that we make. There’s a creature that has light cancelling eyes. Looks like it’s eye structure will have to be completely different than what I originally wanted it to look. One on the front which emits a light cancelling glow, 2 on the sides and on on the back of the head to receive light. Which goes into a bioliogical beam splitter type organ.
Which would absorb more heat when left in the sun: a computer screen displaying black or a computer screen displaying white? Also, do different colors display at different temperatures on computers? (Not left in the sun, but just on its own indoors.) Does blue display any warmer than red for example?
Thats a really interesting question. If we use an old phone with an LCD and no way to turn down the background illumination of the screen then a black screen will definitely heat up more because the lcd crystals absorb nearly all of the sunlight+backlight. If we use a modern OLED display it gets a bit more difficult to answer this question but we can generally say that a completely black oled screen doesn't use ANY current so the device will not heat up from energy losses from the OLEDS and I can't think of any reason that an oled will absorb less sunlight if it is turned on (especially in the IR-range where the OLED doesn't emit light anyway)
I think the vibration sensitivity shows a good demonstration of how high power telescopes need to be vibration isolated. People who have never used a telescope wouldn’t understand that. This device shows a good representation of that. The difference though is that a telescope usually takes longer to settle out after the vibration starts.
Oh my god! That's my idea and I have been trying to make it possible. But it looks like it is impossible unless you put a black hole inside it because black hole can suck light. I am so glad you did this video
You are really funny in a geeky kind of way. I love it when you try doing things that you know won't work for us. Not talking about this video specifically.
This channel doesn't disappoint, I was hoping to see a total cancellation here of the light. What if you did this in a anti-vibration & sound dampening room? an maybe throw in the vanta black as necessary for light control.
Thank you soooo much. This is a wonderful visualization of concepts that come up so frequently in science and science explanation. Truly a service to education.
Minor correction: "Any multiple of a WHOLE wavelength PLUS OR MINUS half a wavelength" will cancel out some of the light. Any even whole number multiple of half a wavelength will produce constructive interference (contributing to the light level) rather than destructive interference (canceling out the light level). A simpler way to phrase the correction is that any ODD NUMBER multiple of half a wavelength will cancel out the wave.
TLDR: No, you can't make a dark flashlight. You will never be able to go shine darkness on people. Our guy will obviously be doing something during the video, but it is not what you would expect from the thumbnail. Just shifting lightwaves for a bit.
I never understood how to cancel light but you gave me an important information i was thinking about an extremely sensitive ground vibration sensor for my snake robot and your laser fringe vibration gave an idea to make one
@ The Action Lab Hey man, nice video again! Just want to correct two things. At 1:35, the trough of the wave doesn't represent low electric field, it represents electric field in the opposite direction to the peak. The peak is upward electric field, and the trough is downward electric field vector. Second is at 7:39. It isn't true that there would be no interference pattern if the mirrors were exactly the same distance from each other. There would still be an interference pattern, but the fringes shift whenever a mirror is moved. The reason is that the laser is not just a single ray of light. The laser light always comes out at slightly different angles, and hence should reflect off slightly different points on the mirror. The entire path of different portions of the light is different, and that's why some places interfere constructively, and other places destructively. So regardless of the mirror distances, there will be an interference pattern. Anyway, great and interesting video! I remember when I took physics III in college, we did the Michelson interferometer, and I took one of the tuning forks in the room and struck it. The When I brought the ringing tuning fork near the interferometer, it actually blurred out the interference pattern. My physics professor and I had two completely different explanations for this. I thought it was because the pressure waves from the sound were moving the mirrors back and forth 440 times per second (I think that was the frequency), and that's why the pattern blurred. He thought the pressure waves were changing the index of refraction in the air to make the light travel at different speeds through the air, thus making it go in slightly different directions.
Hi Action Lab... I wonder if there is any beam splitter " equivalent " for heat waves ? - to cancel out waves from two heat sources. Your thoughts on this?
Hi action lab! Could you please make more videos on quantum mechanics stuffs...like entangled photons,eraser experiment etc !! Btw great video as always
The difficulty in generating this with light and sound is the source of the two sounds originate from two different places. With different wavelengths for anything but monochrome light or a single audio pitch, the location of the cancellation is in different places for different frequencies. A polarizing filter with a 1/4 wave plate makes a unique optical filter. It is not a linear polarizing filter. The combination is often called a circular polarizing filter as it takes the delay of the E field in relation to the H field and this creates the wave that rotates while traveling. So far, so good with the physics lesson. How does it work to make dark? Obtain 1 circular polarizing filter and look through it. You can see through it but it darkens somewhat due to the removal of a polarization. Now the dark.. Look at your self looking through the polarizing filter by looking at yourself in a mirror. Turn the filter over and repeat. Notice anything completely black? The linear polarizer keeps the light in one polarization and he phase plate changes linearly polarized light to circular polarized. If you pass linearly polarized light thru (1) first, either all of the light will be absorbed or transmitted, depending on the rotation. This works as when an electromagnetic wave strikes a reflective surface, the E field is flipped, but not the H field, which reverses (reflects) the wave, but what was a Right Hand twist, is no a Left Hand twist, or visa versa. Now the reflected wave is the wrong polarization to be transmitted. With the filter flipped, the linear polarized light always reflects in the same orientation and always passes with little loss. ( a 180 flip of horizontal is still horizontal ) ua-cam.com/video/6lVIo9C0NDA/v-deo.html
I know it might be late to comment here but I'm curious. Why doesn't the light beam cancel itself out when it is reflected from the mirror after the first time it passes the beam splitter? Does the reflected light have any effect on the light that is going towards the mirror?
Actually even if the mirrors are equidistant from the splitter, there will be an interference pattern. The reason lies on the fact that the image projected are made of multiple "rays" and every ray travels a slightly different amount of distance (called the optical path) and arrive at the screen with different phases anyways. If your projected image is an infinitesimal dot, then there will not be any interfere.
We lost a legend “grant Thompson” in these past few days,we are really sad about it so we don’t want to lose you, please be careful with your experiments!
Please try the "Delayed Choice Quantum Eraser" experiment - it would be so cool because it is a kind of time travel device (for subatomic particles at least)! @The Action Lab
2 points to be noted to see interference: 1. The 2 sources should be coherent. 2. Interference doesn't always show. The distance between 2 mirrors from beam splitter should be multiple of ½ of wavelength + it should not be > coherence length. The wave train should interference with itself and not other wave train to see interference pattern.
Thanks to give some ideas bcoz long time I working on this thing... Could you try with actual flash light which have white beam... So actually i need to know....
If you shine the reflected light on a solar cell connected to an audio recorder, you could record the sound of the vibrations. Like how the CIA or police did/do surveillance with lasers reflected off of windows to hear conversations inside rooms.
Great video, but there is one point that needs to be clarified: it is not enough that the light comes from the same location, to get interference patterns. The light beams must have constant phase difference. So, it is impossible to have the same results using an ordinary flash light, not only because is not monochromatic, but mainly because, like most light sources, including LEDs, emits photons in random phases. As far as I know, only laser light can do the work. Further more, even with lasers, it is extremely difficult to keep the phase difference constant between do different laser devices. So, in order to get the right result, you have to split a light beam coming from the same source, and this source must be a laser.
I've been wondering what causes that for the past 17 years, my mother's bathroom mirror has a mirrored beveled frame around it and it shows the dull dark light bulbs even when they're turned on. Thanks for solving one of life's mysteries yet again.
How could I not mention LIGO!
yeah what's up with that ? :)
I was just about to ask. This is the first video, Ive seen that actually has the experiment and not just a diagram.
Yes I also think about iy
I was LITERALLY going to mention this... lol. You saved yourself a mildly acerbic comment, lol.
The Action Lab first
My brain during exam: *information cancelling device*
I feel like this comment will go top
got a history test....
Me : Light cancellation *fursther procrastination*
Andrei Mihai lwas 6
yeah man
😂😂😂
This is the same setup uses at LIGO that detected gravitational waves :)))
Bach Lan oh yeah it's crazy to think we see gravity with the power of MIRROR
I was about to comment this
Now I understand how LIGO can be so sensitive.
Makes sense, since it's so sensitive to anything at all
@@f.falkwings well, it's this setup deep under ground and spread over a kilometer but yeah it's basically the same setup
The trick is the bigger you make it the more sensitive it is, the one at LIGO can measure differences smaller then the width of a proton
While making this video
Action lab:everybody in the house stop breathing its making the light source vibrate
@@HelloKittyFanMan. tf is wrong with you
@@HelloKittyFanMan. Laying cable
@Freeway
@@HelloKittyFanMan.
You're some kinda demented asshole to think women poop.
@@serious.business i agree
Hello Action Lab!!
Whenever you post a new video, it will be around 10:00 PM in INDIA and after having dinner it gives a lot of satisfaction to watch your science experiments. Thanks a lot and LOVE FROM INDIA♥️♥️
Yeah... I just watched it around midnight... and he explains greatly also
Same I just finished my dinner as well😂
@@AnkushKun hey I'm doing arduino water level indicator using ultrasonic signals. Can you share some resources please.
Thanks for your love😆😆
Pls subscribe to Mystic Dragon EX
Fabulous demo. Surprised you didn’t mention ligo after all that work.
simen jorissen His pinned ligo was posted a day after I mentioned it. It simply didn’t exist at the time of my comment.
@@pbp6741 sorry my bad
There's a type of little kiosk in stores where if you stand in/under them virtually all exterior sound vanishes. Also, sound from speakers in the kiosk did not travel outside of it.
3 words for you. YOU ARE AWESOME. Thanks for giving us all of this stuff!
Love these experiments. I love learning new things that this guy teaches on science. I love that he makes it fun as well as educational.
Really cool aspect to this experiment; you talked about how doing something as simple as walking on the floor can change the phase between two light sources but temperature differences actually do the same thing so if you breathed over one light source you could actually see a phase difference.
I knew about how noise cancelation works with offsetting sound waves by 180 degrees. But I wondered if light cancelation was possible. Whe I thought about it I realized how hard it would be but am very happy now to see it explained in a video. Thank you!
Today's fact: Baked beans are actually not baked, but stewed.
@George Costarica h
@George Costarica d
@George Costarica p
@George Costarica c
WHAT?
Could make one hell of a security system with how sensitive that setup is.
*bird sits on the roof*
>>alarms blaring
Sure, if you're trying to detect a burglary happening in your neighbor's house...
@@AttilaAsztalos I was thinking more of a military base/nuclear plant type perimeter seismic defense system.
I'm pretty sure a physicist could triangulate the exact coordinates of the slightest movements, based on variations in the interference patterns, then pass that data off to a programmer's software, which would automate the relevant security cameras to investigate, and deploy armed drones to intercept a minor threat, or send alerts human security personnel, if more lethal countermeasures are necessary to neutralize a major threat.
This would be way too sensitive for normal civilian use. Every step in the home, speaker bass drop, kitchen appliance, car that passes by, etc., would set off a false positive.
@@Fermion.Wow, this has gotta be a personal best at thread necromancy... ;) Anyway, LIGO detects gravitational waves with the same basic setup and it's just HILARIOUS to read up on what they need to go through to eliminate vibrations caused by, well, everything else...
@@AttilaAsztalos Ahh, you're right about LIGO. I totally forgot about that.
But, the thing about that is that it would be super expensive, with the miles and miles of vacuum-sealed tunnels, and several teams of world class scientists.
And yeah, I made several edits after a few drinks lol.
This video is exactly the reason why i got to know your channel. I had this doubt for a long time and when i searched it in youtube, i got your other videos on additive mixing, subtractive mixing and those on 'if black and white are colours'. Now my doubt is finally cleared. But i can't stop following your channel as your experiments are on the next level. Thanks a lot. It is actually surprising to know that you came to this height from crushing a golf ball on hydraulic press.
Love from INDIA The Action Lab!!! ❤️❤️❤️
Subscribed your channel
i can tell by your name btw cool name
@@bran1039 THANKS! btw that's my father's name...mine is Rishabh Raj...aka... RR
@@barkatrathod9301 hey! Thanks!
@Dhananjay Parasar oo cooler name
A flashlight that instead of lighting makes it dark ... Sooo it should be called unflashlight??? Or flashdark ... ??
Is a "flashlight" really an "unflashdark"?
@@bairfamilyfarm1336 probably.. idk
There is no good word for what we call Flash light or torch.
It can be called LED
@@prism2451 thats why i like arabic .. there is way more vocabulary to precisely describe almost everything :/
We already have an unflashlight or flashdark
We call that opaque object in front of light source
(I guess shadow is dark light, eh)
You are an amazing teacher. Keep up the great work. Thank you 🙏.
ohh! now i understand that's the setup they used for gravitational wave detector !
that much of accuracy is awesome !!!
Wow. This channel has put science into so many of my twin brother and my comic characters that we make.
There’s a creature that has light cancelling eyes. Looks like it’s eye structure will have to be completely different than what I originally wanted it to look.
One on the front which emits a light cancelling glow, 2 on the sides and on on the back of the head to receive light. Which goes into a bioliogical beam splitter type organ.
I really enjoyed that. Beautifully explained.
Blowing my mind again!
Any odd multiple of half wavelength actually.. Since moving by an even multiple will lead to constructive interference..
(2n+1) * wavelength
n€ Z
Which would absorb more heat when left in the sun: a computer screen displaying black or a computer screen displaying white?
Also, do different colors display at different temperatures on computers? (Not left in the sun, but just on its own indoors.) Does blue display any warmer than red for example?
@Musketeer Oliver ...............
interesting
Thats a really interesting question. If we use an old phone with an LCD and no way to turn down the background illumination of the screen then a black screen will definitely heat up more because the lcd crystals absorb nearly all of the sunlight+backlight. If we use a modern OLED display it gets a bit more difficult to answer this question but we can generally say that a completely black oled screen doesn't use ANY current so the device will not heat up from energy losses from the OLEDS and I can't think of any reason that an oled will absorb less sunlight if it is turned on (especially in the IR-range where the OLED doesn't emit light anyway)
It's a close one.
@@redtoxic8701 on lcd there is one light source with layers that make color so brightness on lcd is heat but on oleds? im not sure.
It always a gr8 experience on getting that free knowledge from you sir thanks for all the effort
"Everybody please don't take a shit now it disturbs my not-light."
I think the vibration sensitivity shows a good demonstration of how high power telescopes need to be vibration isolated. People who have never used a telescope wouldn’t understand that. This device shows a good representation of that. The difference though is that a telescope usually takes longer to settle out after the vibration starts.
Just watched this a second time ... the action lab is awesome. Thanks for helping me and my kid learn.
Oh my god! That's my idea and I have been trying to make it possible. But it looks like it is impossible unless you put a black hole inside it because black hole can suck light. I am so glad you did this video
What I have learned: my brain don't want to.
Yeah this one was hard to follow. I will have to watch it again because I'm completely lost right now.
N i x D a
My favorite animal is the spider, my favorite insect is the flea
You are really funny in a geeky kind of way. I love it when you try doing things that you know won't work for us. Not talking about this video specifically.
_Those markers screech through my heart every time..._
Same here. I became extremely uncomfortable. Maybe both of us have pieces of Cat DNAs.
Same bro
The coolest thing about this was how sensitive it was. That was crazy! :)
You are an amazing teacher
i like the Michelson Interfometer so much
This channel doesn't disappoint, I was hoping to see a total cancellation here of the light. What if you did this in a anti-vibration & sound dampening room? an maybe throw in the vanta black as necessary for light control.
Thank you soooo much. This is a wonderful visualization of concepts that come up so frequently in science and science explanation. Truly a service to education.
Really cool! Intresting that you can make a device that sensitive to vibrations, but yet so simple.
u explained it well sir
One of the best things i have seen on UA-cam .
Keep up this good work man, congratulations.
As always the explanation was super clear! Thanks a lot :)
We don't need a flash-dark in 2021,
please continue your work,
we don't need it, but we want it
Loved the video, had a different idea when I read the title. Not disappointed though lol
Love the idea of this! These are the experiments I watch this channel for. We do need to get you a nice, large white board though...
this is basically a mini version of LIGO, they use the same mechanic to measure the tiny mirror movements to detect the gravitational waves
Just one correction. The dots on top of LEDs are primary lenses that are use to narrow the light beam not to open it. All the rest it’s amazing... 👏👏
i didnt think this video would be this cool. nice
This guy is insanely amazing
I love your channel and you just seem like a genuinely cool dude! Much love and support man!
Wouldn’t be a flashlight then now would it, it would be a flashdark. 🤣😂😂
Nyuk nyuk nyuk
Nice video 😀✊
I have been wondering about these since childhood 😁
Minor correction: "Any multiple of a WHOLE wavelength PLUS OR MINUS half a wavelength" will cancel out some of the light.
Any even whole number multiple of half a wavelength will produce constructive interference (contributing to the light level) rather than destructive interference (canceling out the light level).
A simpler way to phrase the correction is that any ODD NUMBER multiple of half a wavelength will cancel out the wave.
TLDR: No, you can't make a dark flashlight. You will never be able to go shine darkness on people.
Our guy will obviously be doing something during the video, but it is not what you would expect from the thumbnail. Just shifting lightwaves for a bit.
Excellent explanation..... so in theory can we make a NAND gate or a Boolean function from this phenomenon?
Amazing video! Learning is so fun.
School teacher: cmon the test is not hard
The test:
thanos sans
So awesome. You think of some fascinating stuff to experiment with!
*Me in the lab doing this experiment*
My friend: *lives*
The lights: 🤯
Me: who allowed you to breathe
This video is more useful than school
😂All is more useful than shool
Your literally the science teacher of the *world*
People on the street: "hey where are my sunglasses?"
Me:
ZZ Top:
I never understood how to cancel light but you gave me an important information i was thinking about an extremely sensitive ground vibration sensor for my snake robot and your laser fringe vibration gave an idea to make one
That's a very cool experiment.
Hey this is a great video! Better than usual!
You're a lot smarter than you sound! 😁😁😁😂❤️ J/k
I really enjoyed this video. Thank you!
Man, you're reading my thoughts!😂 I was thinking of the exact same thing some months ago! Thank you for existing! :)
@
The Action Lab Hey man, nice video again! Just want to correct two things. At 1:35, the trough of the wave doesn't represent low electric field, it represents electric field in the opposite direction to the peak. The peak is upward electric field, and the trough is downward electric field vector. Second is at 7:39. It isn't true that there would be no interference pattern if the mirrors were exactly the same distance from each other. There would still be an interference pattern, but the fringes shift whenever a mirror is moved. The reason is that the laser is not just a single ray of light. The laser light always comes out at slightly different angles, and hence should reflect off slightly different points on the mirror. The entire path of different portions of the light is different, and that's why some places interfere constructively, and other places destructively. So regardless of the mirror distances, there will be an interference pattern.
Anyway, great and interesting video! I remember when I took physics III in college, we did the Michelson interferometer, and I took one of the tuning forks in the room and struck it. The When I brought the ringing tuning fork near the interferometer, it actually blurred out the interference pattern. My physics professor and I had two completely different explanations for this. I thought it was because the pressure waves from the sound were moving the mirrors back and forth 440 times per second (I think that was the frequency), and that's why the pattern blurred. He thought the pressure waves were changing the index of refraction in the air to make the light travel at different speeds through the air, thus making it go in slightly different directions.
Hi Action Lab... I wonder if there is any beam splitter " equivalent " for heat waves ? - to cancel out waves from two heat sources. Your thoughts on this?
Hi action lab! Could you please make more videos on quantum mechanics stuffs...like entangled photons,eraser experiment etc !! Btw great video as always
The difficulty in generating this with light and sound is the source of the two sounds originate from two different places. With different wavelengths for anything but monochrome light or a single audio pitch, the location of the cancellation is in different places for different frequencies.
A polarizing filter with a 1/4 wave plate makes a unique optical filter. It is not a linear polarizing filter. The combination is often called a circular polarizing filter as it takes the delay of the E field in relation to the H field and this creates the wave that rotates while traveling. So far, so good with the physics lesson. How does it work to make dark?
Obtain 1 circular polarizing filter and look through it. You can see through it but it darkens somewhat due to the removal of a polarization. Now the dark.. Look at your self looking through the polarizing filter by looking at yourself in a mirror. Turn the filter over and repeat. Notice anything completely black?
The linear polarizer keeps the light in one polarization and he phase plate changes linearly polarized light to circular polarized. If you pass linearly polarized light thru (1) first, either all of the light will be absorbed or transmitted, depending on the rotation.
This works as when an electromagnetic wave strikes a reflective surface, the E field is flipped, but not the H field, which reverses (reflects) the wave, but what was a Right Hand twist, is no a Left Hand twist, or visa versa. Now the reflected wave is the wrong polarization to be transmitted. With the filter flipped, the linear polarized light always reflects in the same orientation and always passes with little loss. ( a 180 flip of horizontal is still horizontal )
ua-cam.com/video/6lVIo9C0NDA/v-deo.html
This was a good episode
great work sir.
Mr.Sketch pen teacher 😊😊😊🥰🤩🤩
Awesome video, as always.
Im so sorry for your loss
I know it might be late to comment here but I'm curious. Why doesn't the light beam cancel itself out when it is reflected from the mirror after the first time it passes the beam splitter? Does the reflected light have any effect on the light that is going towards the mirror?
Actually even if the mirrors are equidistant from the splitter, there will be an interference pattern.
The reason lies on the fact that the image projected are made of multiple "rays" and every ray travels a slightly different amount of distance (called the optical path) and arrive at the screen with different phases anyways. If your projected image is an infinitesimal dot, then there will not be any interfere.
We lost a legend “grant Thompson” in these past few days,we are really sad about it so we don’t want to lose you, please be careful with your experiments!
Such a good channel
Another , excellent , video
Please try the "Delayed Choice Quantum Eraser" experiment - it would be so cool because it is a kind of time travel device (for subatomic particles at least)!
@The Action Lab
Me: just how sensitive are you?
Soft boy: have you ever heard of a Michelson interferometer
2 points to be noted to see interference:
1. The 2 sources should be coherent.
2. Interference doesn't always show. The distance between 2 mirrors from beam splitter should be multiple of ½ of wavelength + it should not be > coherence length.
The wave train should interference with itself and not other wave train to see interference pattern.
Thanks to give some ideas bcoz long time I working on this thing... Could you try with actual flash light which have white beam... So actually i need to know....
you also build an motion detector with this experiments... or an vibration, quite cool!
Wow this is really cool. Too sensitive of a system for everyday use though.
If you shine the reflected light on a solar cell connected to an audio recorder, you could record the sound of the vibrations. Like how the CIA or police did/do surveillance with lasers reflected off of windows to hear conversations inside rooms.
Great video, but there is one point that needs to be clarified: it is not enough that the light comes from the same location, to get interference patterns. The light beams must have constant phase difference. So, it is impossible to have the same results using an ordinary flash light, not only because is not monochromatic, but mainly because, like most light sources, including LEDs, emits photons in random phases. As far as I know, only laser light can do the work. Further more, even with lasers, it is extremely difficult to keep the phase difference constant between do different laser devices. So, in order to get the right result, you have to split a light beam coming from the same source, and this source must be a laser.
So well explained! one of your best videos! I think I know how gravity waves were measured now :D
Wow, this could be a great movement sensor.
Dark Shade yes they should make a gravitational waves sensor using this system.
Have I just watched how Ligo and Virgo work? :)
Upd: I see, you mention it in your comment :))
I met James today at lagoon, big surprise :D
Great video dude
“Hey guys, today we’re going to be...”
Every time
This man have big problem with light
BTW big fan
Props for drawing all these explanations I'm sure it can tiresome after a while
LIGO which is used to detect gravitational waves uses this principle only.
LOVING IT
Tq fr the video, action lab love❤️
I've been wondering what causes that for the past 17 years, my mother's bathroom mirror has a mirrored beveled frame around it and it shows the dull dark light bulbs even when they're turned on.
Thanks for solving one of life's mysteries yet again.