Meta-Materials: Invisibility Cloaks, Superlenses, And Earthquake Protection

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Metamaterials are the next technological stage “after” materials. It’s a research area that has progressed incredibly quickly in the past decade, and that includes superlenses, invisibility cloaks, earthquake protection, and also chocolate. Yes, chocolate. What are metamaterials, and what are they good for? That’s what we’ll talk about today.
The 2000 PRL from Pendry is here
journals.aps.org/prl/abstract...
Aaron Danner's raytracing paper is here:
citeseerx.ist.psu.edu/viewdoc...
The paper from Lee et al about the first superlens is this:
link.springer.com/article/10....
The paper about the hyperlens is here:
www.nature.com/articles/s4159...
The infrared invisibility cloak that hides the mouse is here:
onlinelibrary.wiley.com/doi/e...
The video from Hyperstealth Corp is here:
• Hyperstealth Invisibil...
The paper about magnetic metamaterials to improve wireless power transfer is here:
www.nature.com/articles/srep0...
The paper about the acoustic directional reflector is this:
journals.aps.org/prmaterials/...
The paper for hiding from ultrasound underwater is here:
arxiv.org/abs/1009.3310
The paper about the acoustic invisibility cloak is this:
www.nature.com/articles/nmat3901
The two papers about earthquake protection are those:
ieeexplore.ieee.org/document/...
www.frontiersin.org/articles/...
And the paper about meta-chocolate is here:
pubs.rsc.org/en/content/artic...
00:00 What are Metamaterials?
01:38 Negative Refraction and Superlenses
08:24 Invisibility Shields
11:58 Phononic Crystals
14:00 Earthquake Protection
16:25 Meta-Chocolate
17:12 Sponsor Message
#science #technology #metamaterials
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Many thanks to Jordi Busqué for helping with this video jordibusque.com/

[@xenphoton5833]

When you wrapped the foam around your face and suggested it as a way to "drastically improve your experience of the world". I can always count on you making me smile at least once throughout your videos. 👍 Thank you!

[@drmemento]

More subtle, the holes in the foam reminding her of cheese - as many things seem to do!

[@Patrik6920]

Ive tested it, it dramaticly Increases the experience of some youtube videos

[@kasroa]

I believe this is the only known way to avoid news about the Royal family at the moment

[@cHAOs9]

Its even better if you can just get everyone else to wear one

[@auldteuchter9012]

@@kasroa Why, what's happened....?

[@zooblestyx]

Not many people know this, but Sabine's sense of humour is actually made from a cutting-edge hyper-hydrophobic metamaterial.

[@michaelmeredith912]

Lol 😆

[@bongobrandy6297]

A Bond martini, stirred.

[@precursors]

Her sense of humor is also oleophobic.

[@RogerBarraud]

A rabid sense of humour?

[@bkparque]

I believe it

[@johnregan2882]

Sabine, Thank you for providing "humor in science" along with the education.

[@not_elm0]

So true!

[@donquixoteupinhere]

You are one of my favourite science communicators, full stop! No nonsense, serious business… with a sprinkle of joviality. Thank you Sabine, you rock! 🎉

[@stefflo712]

Apart from that one video where she talks about how capitalism is good :D

[@lbgstzockt8493]

I've only recently discovered your channel, but the way you combine interesting science with a great way of talking makes me really happy.

[@sweebos]

I literally just finished the videos on wireless power and 5g, where Sabine asks if we wanted to know more about meta-materials, and thought to myself, "yes please." This video was just in time. 😄 Thanks for sharing all this knowledge, it's greatly appreciated. ✌️💙

[@scoreprinceton]

How soon will we have a video on meta-non-materials?

[@garcoleuphrates4734]

@@scoreprinceton It accompanied

[@scoreprinceton]

@@garcoleuphrates4734 No wonder I missed it!!

[@grayaj23]

Thank you... I have tried to explain to friends where the word "metaphysics" came from, but they don't believe me. They want to believe it means something like "better than physics" or "more important" or "transcendent over". My undergrad metaphysics prof thought this idea was funny and treated the truth like an inside joke. What it means is "the book that came after we compiled the book on physics", because there wasn't a more formal name for the topic yet. I once had a cat that had a litter of seven kittens. One of them ended up named "the other cat", or O.C. for short, just because we didn't know she existed until a few hours after the first six were born.

[@csmac3144a]

This is an incredibly naive and impoverished understanding of what we mean by metaphysics. It is shocking how many otherwise intelligent people are afflicted with a sort of cognitive scotoma with respect to categories such as the metaphysical. Naïve positivism at this stage of human intellectual development is an embarrassment, like the time Hawking committed 12 or so basic logical fallacies in the first few pages of one of his books.

[@grayaj23]

@@csmac3144a The idea of metaphysics and the nature of existence is generally too esoteric for people outside of the interested communities to want to spend much time thinking about. It's naive, but that's all it *could* be, because people are people.

[@briangarrow448]

I’m still waiting for the invisibility cloak I ordered from an advertisement at the back of a comic book in June of 1968. Perhaps it will come in the same delivery as my Sea Monkey order.

[@ryo0o0o88]

I love Sabine, her cute German sense of humor, her intelligence is up there with all the great minds, and her ability to entertain while teaching is so refreshing to watch;

[@kb5zuy]

".. it's not what a fish is supposed to do." Love it. Thank you.

[@birgerjohansson8010]

An important application: I read that a metamaterial 'Lens ' for ultrasound could make ultrasound check images four times sharper, for the benefit of expectant mothers worrying about the fetus.

[@collin4555]

I imagine it would also make ultrasounds more useful for other diagnostic purposes as well. On several occasions I've been given an ultrasound which detects some mass is present, but can't get any clearer detail and needs additional imaging. So it'd be even more good news all around

[@ElDJReturn]

I love your humor. Well timed and also very informative and insightful knowledge in between. I'm so glad I found your channel. Thank you for making science not only accessible but also entertaining.

[@rickseiden1]

Dr. Hossenfelder, if you ever decide to give up on physics, I really think you'd have a great career as a stand up comic. You're very funny, and your ultra serious delivery makes it so much funnier!

[@mikecope806]

German humor is no laughing matter!

[@timesathousand]

I love Sabine's deadpan, snarky interjections.

[@-_-president-_-richardson-9705]

Hello Sabine.Your videos really helped me during certain tough times in my life and one of your notifications saved me from suicide.Thank you.

[@-_-president-_-richardson-9705]

@Arbane's Sword of Agility Your god and your religion are the things that made me depressed twice during childhood and I don't need them anymore.(Btw the notification thing was 6 months ago,I am doing a lot better now)

[@SabineHossenfelder]

I'm sorry about your difficulties. I understand the situation well. Please take good care of yourself.

[@-_-president-_-richardson-9705]

@@SabineHossenfelder Thank you.I will

[@-_-president-_-richardson-9705]

@Arbane's Sword of Agility Orthodox christianity,gnosticism and new age religions.Tried all of them during my early childhood years and they didn't help me at all.

[@-_-president-_-richardson-9705]

@Arbane's Sword of Agility I have.Things are slowly getting better for me.I still have social anxiety,body dysmorphia and rumination but it has been better than usual.

[@Kram1032]

Would it be possible to use an accoustic invisibility cloak to significantly reduce the sound of ships' motors without impacting the ships' ability to travel? Because honestly that does sound like something incredibly useful: Since sounds travel far farther in water than in air, noisy ships have become a huge problem to marine life. (I suspect it'd also be useful for covert military application, but honestly, if it's possible at all, it should kinda be a standard feature of boats in the future. This sound pollution is a rather big deal) In fact, "hiding from dolphins" is exactly what this would be for: Whale songs have changed to far higher pitched just to be able to hear each other over the constant drone of large ships.

[@punditgi]

Very interesting! Thanks for the video. And your comment about frequent zooming in KZbin videos is spot on. Those folks should be fined for each instance. Also, you make a very fine Egyptian hieroglyph, Frau Doktor! 😃

[@MrWildbill]

That was a really great intro to Meta-Materials, perfect balance of digestible information and humor. It will be interesting to see what we get when and if some entrepreneur gets their eureka moment.

[@stellarshriner]

My favorite Saturday morning class and teacher. I love the knee slappers. 'uhh yucka yucka yucka' Thanks Sabine

[@rickkearn7100]

Our host "walked like an Egyptian"! This subject post was so well presented (and satisfying) that when I finished watching it, my brain lit a cigarette...

[@c_b5060]

Well said.

[@jamielondon6436]

12:15 I cannot even put into words how satisfying it is that there actually is a reference to cheese in the video! :-) Kudos, Dr. Hossenfelder, well done!

[@AlienScientist]

Look up Edgar Fouche - Former Area 51 Employee who talked about metamaterials and invisibility research back in 1998. That's where I first learned about Metamaterials back in 2004... I have been researching them ever since!

[@rayoflight62]

Metaphysics is, for all practical purposes, a branch of philosophy. The study of metamaterials must therefore be the quest for the material a philosopher stone is built from. A similar material with a negative refractive index was referred in a paper from Isaac Asimov, the thiotimoline. Thiotimoline had a negative solubility time...

[@ldbarthel]

Ah yes, "The Endochronic Properties of Resublimated Thiotimoline". After creating endochronic polymers, it became possible to use the endochronicity to counter the effects of relativistic time dilation in space flight. (Yes, THAT guy again.) cf "Thiotimoline to the Stars".

[@Blowfeld20k]

@@kensho123456 You do get that they are mostly just referencing a trope from a scifi book, don't you ?

[@Blowfeld20k]

@@kensho123456 No problems, but I strongly advise trying some book scifi, it usually takes interesting science concepts much more seriously than the likes of Star Trek and Star Wars.

[@virginie_fabrice]

hi sabine i was a school collapse teen once but each time i watch your videos i feel like i was successful in my studies thanks for that and bravo for your work

[@virginie_fabrice]

your videos are my prize sabine thanks

[@naughtyrobutt]

Best sense of scientific humor online

[@lukedowneslukedownes5900]

I just came from your newest video. I must say I’m so excited for the future of meta material

[@dannypope1860]

❤️ you Sabine! Never lose your sense of humor!

[@nicholascurran1734]

I always enjoy your videos, the topics are typically interesting and well presented.

[@Teh-Penguin]

I cannot express how much I love the dry humour in these.

[@JohnSmith-ju1gi]

I love your videos and your sense of humor. I especially like that I believe that some folks don't even know when you are being funny. I watch and smile and enjoy that the world has people like you.

[@lanekarabani8084]

LOVE you pr approach to humour in science. You’re perfect omg

[@davidfalgout7304]

I could listen to you explain the world around us for hundreds of years!

[@Vatsek]

A selfie camera permanently attached to one's face. What a brilliant idea.

[@flatworm00]

A really cool presentation...there is so much going on in this world that we don't understand, it is fun to get a quick glimpse

[@theophrastus3.056]

I always look forward to Sabine’s take on things.

[@hp127]

What an interesting theme. Thanks for the introduction.

[@smb10011001]

Sabine's dry humor never fails to tickle. Thank you!

[@TheMemesofDestruction]

8:38 - The subtle Trolling is beautiful. ^.^

[@GururajBN]

New material science for the engineers to master. This was something I had never heard of. Many thanks for imparting this new bit of knowledge.

[@nacoran]

You had me at meta-chocolate! I've always had an idea for a large sculpture (not a sculptor, just an idea I have) where the sculpture is ringed by a series of transparent pillars with various angles of refraction across their surfaces. It would allow the figure to face you from different directions- sort of a more complex version of the Mona Lisa eyes, and then to appear different when you go inside the circle of pillars. (Some of the techniques from sculptures that only line up into an image from one direction might be involved too).

[@_ninthRing_]

The metamaterial I'm most familiar with is a type of paint which absorbs virtually all of the light which impacts it. It does this by redirecting incoming light waves into a labyrinth of nanostructures, with the result of being close to the blackest black possible (96% absorption). It's actually really bizarre to see in action, as any object painted with it becomes an abyssal silhouette that lacks any defining features other than the outline.

[@r0cketplumber]

Nighthawkinlight demonstrates a metamaterial with the exact opposite effect- extremely high reflectivity in visible light combined with high emissivity in IR. kzbin.info/www/bejne/hGTFe6GBosqBgLs

[@symbolspangaea]

Thank you so much for this beautiful video! Really eye opening !

[@nixdorfbrazil]

Love you! Keep it going, Thanks for your amazing perspective! I also like the script was written, so praise the writers. And the editing.

[@justinahole336]

Now I have "Walk Like An Egyptian" stuck in my head!

[@pumbaa667]

Damn, there is so much jokes in this episode that this channel will soon become a comedy channel :D Lovin' it Sabine, keep it up.

[@nowzarybijan7956]

Grossartige Fähigkeit bei Sabine : Great ability to make science accessible to people ! That’s really wonderful ! Toll

[@BRUXXUS]

How can I get into a research study about the meta-chocolate?

[@dogcarman]

Asking an important question here. 👍

[@sarahrosen4985]

I am willing to be a test subject.

[@helmutzollner5496]

Excellent video. Thank you for sharing!

[@UncleSmokey]

Love this video. Thank you Sabine! This was very informative 👏. Earthquakes wow!

[@darenmccormick2115]

"well that does away with selfie-sticks” Lmao 🤣🤣 Your brand of humor is pure gold

[@Cre8tvMG]

I appreciate your nerdy humor, along with solid scientific information. Keep having fun. Science is wonderful fun, not just serious business.

[@geckel2145]

Danke Sabine, your videos are always great!

[@Descriptor413]

This is definitely in the personal horn tooting category, but in my Master's degree, I studied the use of microwave frequency metamaterials for use as strain sensors. Basically, metamaterial sheets (here called Frequency Selective Surfaces) act like notch filters at a certain RF frequencies, allowing certain frequencies of EM radiation through and reflecting others back, kinda like a colander. The trick of it is that the frequencies where this happens is dependant on the size of the metallic elements that make up the metamaterial. Because the frequency response is dependant on geometry, if you stretch the material, the resonant frequency shifts. We used this as a fancy strain gauge, which could be useful, since you can embed it deep within an opaque object, and then determine strains occurring at that point by simply interrogating it with an external electromagnetic wave and seeing what frequencies come back. That being said, the applications are still somewhat limited, but it's an interesting use. It also suggests that metamaterials are weak against strain, and thus if they are deformed, it could cause a shift in its behavior, so something to look out for that I don't hear talked about too much.

[@MTerrance]

Okay - you got me. "It also ruins your makeup" hilarious. Your on-liners are killing me.

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[@phy6geniuxYTcreations]

This is my current field of research, electromagnetic metamaterials. Thank you!

[@s.vidhyardhsingh3881]

Your humour is rare if not one of a kind 😂😁👍🏻 This video is amazing!!! A lot learnt ..

[@0neIntangible]

I foresee and anticipate the meta-material development of composite alloys for fabricating wave channeling envelope skins of high speed vehicles/aircraft/submersibles/projectiles to drastically reduce friction with the air or water, reducing the heating effects while allowing increasing the rates of speeds through the medium, and possible stealth characteristics.

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[@teashea1]

Your humor is so excellent..........................

[@bazpearce9993]

Brings new meaning to the phrase "A trick of the light."

[@capitalistdingo]

I could be mistaken (and maybe I just missed it in the video because I was multitasking) but I think there may be more types of meta-materials than these. The changes in the materials can be more than just structural. Adding different materials in regular intervals can creat something with properties that a regular alloys or composites don’t have and these properties can be things much different than adapting the way waves propagate through the substance. I imagine that using elements with mechanical abilities that we could change on command or which change in response to certain conditions could allow all sorts of applications beyond my ability to predict.

[@SabineHossenfelder]

Yes, sorry, didn't mean to imply that those are the only possible meta-materials. Those are the ones on which there has been the most research.

[@josephgdangelo9807]

The only way to obtain invisibility its to make sure none of the light reflects back to the observer. But in that case you would see black. So there's 2 parts to it. Stopping an object from reflecting while also allowing the background to be reflected to the observer... not so easy.

[@4draven418]

Thank you for an interesting video. Lot of progress being made in this and related areas, very difficult to keep up with it all.

[@KeithCooper-Albuquerque]

Great video, Sabine! It will take me a little time to reflect on it though ...

[@D3GamesOficial]

I loved the lens mini class

[@alcyone1349]

Well, this video is so well done that even I, a layman, understood it. Thanks Sabine!

[@llamallama1509]

Could superlenses be used in microchip manufacturing to photographically etch even smaller chip features than currently possible?

[@SabineHossenfelder]

Interesting question. The wavelengths for which superlenses have been manufactured so far don't lend themselves for this purpose. The ones I have read about were all below the visible range. However, it's possible that I have missed something, and in any case, I can't think of any reason why it shouldn't be possible.

[@hzdvb]

In principle, yes, but it seems unlikely that it would work. Currently, we use EUV light at 13.5 nm for lithography. The problem with EUV is that pretty much everything is absorbant in this wavelength region. Therefore lithography optics in EUV don't use lenses but rely solely on parabolic mirrors to focus and redirect light, and even that becomes difficult. The superlens would need to transmit a sufficient amount of light and not be damaged by the intense EUV radiation, which doesn't seem likely.

[@JanBruunAndersen]

I was about to ask the same question.

[@kylebowles9820]

@@hzdvb usually the photonic metamaterials I read about use the electrons in conductors to interact with the light. The resulting interface having different properties than the bulk material, hence metamaterial. I don't know much about resilience to EUV, but it really comes down to the conductor efficiency; making the ultra tiny structures able to handle the energy. In EUV research they use gold; but in an industrial setting it would probably be prohibitively expensive.

[@peca87bg]

@@SabineHossenfelder speaking about interesting properties of meta materials. Some researchers focus on mechanical response such as negative Poisson’s ratio. But, did you know that an fcc single crystal has negative Poisson’s ratio when pulled along [110] direction? The thing is that for some interesting mechanical response we don’t need to build metamaterials.

[@XmarkedSpot]

This was a particularly delightful episode, I can't adequately express my gratitude for the #meta joys you bring

[@edreusser4741]

I love you Sabine! And I love listening to your videos. Even the old ones.

[@whatsapp-.3481]

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[@BigZebraCom]

I was going to create some meta-materials--but then things got really busy at work.

[@dimension2788]

Nice job on meta materials its a massive subject and Sabine did a super job on super lenses. Pendry has some very interesting lectures on this and his sense of humor is meta funny. I highly recommend the ISS lectures with Pendry what a brilliant scientist!

[@Lord0fTheCheese]

thanks for another entertaining and educational video.

[@yangpachankis]

Ah! This is so brilliant! So that is why the opaque observatory worked!

[@jamesduncan6729]

Sabine was extra snarky in this video. Love it. This woman is a personal hero of mine 😆❤️❤️

[@dazeitem]

I love the use of comedy in this episode. It somehow makes it easier to understand now.

[@viliamvolko6865]

I used to watch these videos for the science. Now I watch them for Sabine's genius cheesy jokes 😂.

[@euanthomas3423]

Good text on the optical aspects: "Geometry & Light : The Science of Invisibility" by Ulf Leonhardt & Thomas Philbin (Dover publications). However not for the mathematically faint-hearted. Nice video.

[@chrisfuller1268]

Yes an excellent example of conformal mapping!

[@ismarcintora2263]

Always very clear and scientific explanations, thank you. I.Cintora, MD.

[@whatsapp-.3481]

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[@annestephens9631]

Marvellous 🙂- Thank you for another fine video.

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Love your content. Thank you

[@mrs.joeschmoe5681]

Joey.... what did you win? JW ☺️

[@SykPaul]

Dr Sabine, have mercy

[@patrickw9520]

Sabine reminds me so much of my HS chemistry and German teacher.

[@PhilipRhoadesP]

Another interesting and amusing podcast!

[@AethyrPrime]

I think you missed a major opportunity by not referencing the Yatuja aka “The Predator”.

[@KarimDeLakarim]

Love you Sabine.

[@10minutes_Physics]

amazingly brilliant!!

[@marcfruchtman9473]

Thank you for this video.

[@Zift_Ylrhavic_Resfear]

Thanks for the video :)

[@hihungryimcam]

That random Egyptian pose made me laugh out loud. This was a great video as always.

[@TheAntibozo]

Love your videos, Sabine. 🐿

[@juliana.x0x0]

Whenever it almost starts to get a bit overwhelming, a lot of information to process at once, she slips a funny little line in, somehow stopping me from overthinking and I end up understanding better and having a good time while doing so. She’s funny and very sharp, I’d love to kick it with this chick!

[@KrystelSpicerMindArkLateralThi]

🤣Love it. Great show. This ep makes me wonder just how long it's going to take us to come up with all solutions though at the rate we're going.

[@warrenfriedman156]

Classic video. Thank you.

[@MrFoolingyu]

Metaphysics has just taken on a whole new meaning .

[@vauchomarx6733]

Gotta aim for an Ignobel Prize now, by developing a method to calculate the number of Sabine's eyebrows. I see this is becoming a running joke on the show… ;)

[@CAThompson]

Or, something with dairy-based food materials.

[@Bassotronics]

Probably somebody not long ago mentioned her eyebrows for some reason and she’s getting back to that person.

[@yadt]

A fairly easy calculation: 1 + 1 = 2

[@ernstoud]

The number of *hairs* in the eyebrows is the question. I don’t think the answer 2 will get you the Ignobel prize.

[@francescos7361]

I was stupid as student but perseverant so great competencies and educator.

[@greg4367]

Greetings from San Francisco, Sabine. Here's a challenge for next week: Can we you work a reference to BOTH Einstein AND cheese? It would make my Saturday complete.

[@whatsapp-.3481]

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[@sherriec5258]

The orange plastic dish with the spirals that "changes the refractive index" reminded me of Stonehenge. That's the first thing that popped into mind.

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[@alterego3734]

With metamaterials with a refractive index smaller than one (but positive), things can be made to appear further than they are. With asuch materials, we could make fake windows with scenery that appears far away.

[@WarrenLacefield]

Rear view mirrows already do this. Or try looking through binoculars backwards.

[@chrisfuller1268]

With a refractive index of zero, light appears to move faster than the speed of light, but it does not really because metamaterials store energy causing the strange effects. With a negative index the light appears to move backwards in time.

[@ShaunVillafana]

My favorite topic! ❤️❤️❤️❤️

[@robblerouser5657]

I love these types of videos!

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