Thank you, Jenny. I'm an artist. What do artists do? We've heard from an artist there and very eloquently about some of the aims and goals of artists. It's odd as an artist, I think, because you feel a little bit isolated. You feel like, what are your goals in life? I've come to the conclusion that my goal in life is to show us to ourselves. In that way, I'm about challenging culture, really, and pervasive culture, culture that we don't necessarily know is around us, making it visible. It's been really interesting sitting here and listening to all of you talking, all the speakers talking, and that's exactly what you're saying. It's about challenging culture, and more than that, creating culture, which I think lots of artists don't like to admit they're doing, but I think they're trying to do that.  This is where it all started for me, and I'm going to take on a bit of a story of what I've been doing and what I hope to be doing in the future and hope that it has some meaning for you. When I was at school, I used to stare out of the window a lot, and I used to also pretend I was an animal a lot, and these two things were quite important to me. One day, the teacher called my mum in to school, and she said, look, he's just staring out of the window all the time, he doesn't do any work, and there's a genuine worry about this. To my mum's credit, she said, that's him being creative. She told me that recently, and I didn't know this, and I thought that was amazing that she recognised that, and that's something that's taken me almost this long to realise, that's been my battle in life, to understand the fact that my imagination and the world that I can enter, which isn't this conscious reality, is equally as significant as this world. So this is me, up a tree, and I am not pretending to be, but I am a bird, quite a rare bird called a goss hawk. As you can see, I am that bird. Now I am believing that I am that bird. Now this is me challenging the idea that we live in one reality. This is me thinking my imagination in that I can believe in enough to believe that I can be something else. Now I got someone to take this picture, they're quite a long way away, just to show me that it didn't work, because actually when I was up there I was really believing that I was, and it's this kind of commitment to my imagination, this sort of immersion that's been really important. Also this idea of becoming an animal, it seems to be quite a good vehicle for me. I started to do this myself, and I was the test for this, to see what this would do, how much I could believe in this. Then I started to take it out into the real world, and this was a residency I did in the Galapagos Islands. I have a big problem with conservation there. The animals are basically more important than the people that live there. I did a report for the local TV news as a blue-footed booby, this quite rare bird, iconic bird of the island, so I dressed up and made this homemade costume, and I walked around the town, sometimes driving on the back of this truck, like the potmobile. I could say things, and I noticed things because I had this other perspective, because I was able to enter into this other world, which was entirely of my own creation, I could then have perspective and see things very clearly actually. Also, I could say things that probably weren't being able to be said by politicians and other local people, that were quite contentious, but ultimately I think quite healing, because in a way I wasn't a threat, I was just an animal, I was just in my imagination. As a society, I think generally devalue that place, we don't give it the significance it needs. Then I went further on, and I thought, well, this imaginative world I have, I need to really test this, I need to put this on the line. If I'm going into my sort of dream space, so I'm going somewhere now, and it's very real for me, and I'm coming out and telling you about it, and then I'm in again, I became quite good at this, going somewhere real and seeing things, and I thought, how can I test this? Maybe people can ask me questions, if I could answer those questions, and I could find a logic within this, I could bring this back into rationality, I could make this sort of functional and pragmatic. So I've sort of went on the journey around the world, asking people to ask me questions. I went to Stavanger in Norway, and I asked them there to ask me a question. He asked me a question about prostitution there. I went to Japan, and the Tokyo City Council asked me a question about cycle parking, and then I went to Israel, and I saw the mayor of Halon, and I was in his office with him, and he asked me a question that was sort of related to the Palestinian crisis. Now all these things, I don't really know much about, but the idea for me was, if I trusted my imagination enough, if I trusted the idea of unconscious thinking, the idea that I do have knowledge, and that I do have experiences that are valuable, then I could hopefully relate to anything that comes my way. So within all these things, I felt like I was offering an insight through an unconscious process. I was finding a rationality that wasn't being used before in very intractable circumstances like this. And then, more recently, I spent about four years in the Elephant and Castle. In London, if you know the area in South London, it's quite a historically deprived area, and there are big plans to knock it all down, all these 60s housing developments, and there's a big vision, really, by the council, by the mayor of London, by the government, all these big agencies bought forward their visions for the Elephant and Castle. And I just thought, that's what I'm dealing in. I'm dealing with visions. I'm having visions. I'm talking to people about these visions, and these visions are powerful, and they have information in them that we need. So I thought, okay, well, I'm going to have my own vision for this place. Now the official vision is basically knocking down all these council flats, and about 3,000 people live there in the Haygate estate, and building luxury flats for rich people. So basically all the people in these flats have been now moved out and dispersed across London, and that's dispersed all the communities that exist there, and all the amazing interactive, sort of, or interconnected roles that people played for each other, the informal network, really, of people. And the council did their own consultancy process to decide what they should do with the people there and their input in this, but it turns out that the people there actually have their own vision. They won't ask for their own vision. So I felt like I should, in a way, find a vision, really. So I went to see the council and got them to have their own visions. This is the planning department in Southwick Council who are responsible. So rather than the corporate vision, I said, well, come on, what is your personal vision? So they went into their imagination and dreamt up some quite amazing things that would have been amazing for any way. And then I teamed up, and I did this with residents and office workers and developers, all the people involved. And I teamed up with this band called Chromehoof. I noticed the Chrome. And you'll start noticing that there's quite a lot of costume involved in my work. And they're kind of a death metal, sort of psychedelic punk amazing band. And I thought, OK, how can I... How can I communicate this vision? How can I actually have a vision? I've heard all these other people's visions. I think I need to supplement those and maybe have my own. So we decided to put on a concert in the Coronet Theatre in Elephant Castle, which seats about 1,300 people. And this was really a culmination of everything that I'd experienced. A very sort of physical consultation, a very visceral consultation. Not really language-based. It was just about, in a way, expressing what... I suppose expressing a vision in a way that has some kind of link and connection to the people it was affecting. Beautiful seals. Beautiful seals. Beautiful seals. Beautiful seals. Beautiful seals. Beautiful seals.  So after this odd consultation, I went back to the council and I had to remember what I'd seen, really, in my imagination, what I'd come out with this improvised performance with Crome Hoof. None of that was planned. We just had a beginning and ending and we were on stage for about an hour. And I went back to the council and I saw these seals and I saw these geese do this stuff. It's always animals with me and I saw these swallows. Anyway, the upshot was that they really had a responsibility to these people. And there's something called sight tenacity, really, which I recognised in swallows. They're very loyal to sight and that's a very physical embodiment of psyche and it's very important to people. And once you start breaking that up, you start breaking up very, very complex communities and in a way it's impossible to just invent community which they're trying to do. The idea of acting politically in this imaginative way was quite important, but then I started to think about what is the imaginative world itself? What does it do for us? How does it really relate to life itself? And I started working in a hospice in North London. I worked there for about two years, off and on. Well, every week I went in and I had lunch with patients there. And we just started talking. And the patients started to say, well, what are you doing here? I said, well, I'm artists and residents. I've set this thing up and I'm just chatting to you. And they said, yeah, but what are you actually doing? And I said, well, what can I do for you? And they said, what can you do? And I realised, what actually can I do? And I said there's a breakdown what my skills are. And as an artist I never really asked that. I'm sure you're asked that a lot in business. So I said, well, I trust my imagination. I believe through it. I think it's significant. It's important. I think there's truth there. I think there's knowledge there. And there's huge untapped resources there. And it turns out that all of them, because they were generally confined in their hospital hospice rooms, they were really living through their imagination. They were relying on their imaginations to create a world for themselves. So the conversations became quite interesting in that sense. And there's one guy, Alex. He told me, well, I've always wanted to go to the Amazon. I've always wanted to go and see this very, very remote tribe. I always wanted to go and ask them these questions. I said, well, are you doing that in your imagination? He says, yeah, I am, but I've only got so far. You know, I need to know what's around the next bend of the river. I need to know what they're going to say. I can't invent that stuff. So I said, okay, I'll do that. I'll go and be your imagination. I'll travel to the Amazon. So I got the funds together. It took about three days to get to this tribe. And I spent about three days with them. And then I came back. And as soon as I got off the plane, I went back to Alex at the hospice. And he just grilled me about my trip. And he didn't even call it my trip. He called it our trip. It's like he went on this trip. And he just asked for all this information that he needed. And in the end, he died about three months later. We talked again before he died. And he said, this was amazing. It gave me, when I was really suffering, it gave me the extra bit of jungle to explore, the extra other conversation to have, the extra other place to live through, either because the pain was bad or because he was so confined. It was a very real place for him. And that for me was a real testament to what I've been trying to do in a way, which is to acknowledge our society's dependence, or over dependence on the rational conscious world. We are over-dependent to our own suffering, really. And we only realise that we live throughout imagination so much when we are forced to. So I wrote this book called A Practical Guide to Unconscious Reasoning. It's quite a light title, I think. Trips off the tongue. It should be the Almanac, shouldn't it? Anyway. So this is really a book I wrote last year. And it's really trying to sublimate all that experience that I had and think, okay, this is open to everyone. This is practical skills. These are skills that everyone should have, really. And it's really a handbook for the imagination.  But ultimately, it's asking you to put your imagination to the test. It's asking you to risk utterly letting go and not think, let your images you have guide you and notice what you see, notice what you experience and bring those back. But do that with a task. Preferably a question. And the reason, really, for writing the book was because I started doing a few workshops.  We're going to go on a journey now in imagination. We're going to walk down this road. We're going to walk about a minute. We stopped.  Did you manage to see anything? He said, well, I've had my eyes closed. I said, yeah, I know. But did you see anything in that darkness? Did anything come through? He said, no, because I had my eyes closed. I couldn't see anything. So in a way, it really showed me how the degrees to which we live our lives through this. And I think some people do it more than others. And I think that's obvious. I don't really utilise this much. And to that end, I thought, okay, right, let's create a school. So I created a school of the imagination. And it only ran for a week. But I did it in the East End. And I asked people, I put it at an advert. I said, who wants to be in the school of the imagination? And lots of people came in and I interviewed people. But most of the people came from this organisation called Carball Citizens, which is people who have been homeless at some point. And they had this amazing ability to be able to let go and invest in their imagination, a wonderful skill. So we basically trained up. We trained up by understanding different perspectives, understanding our own personal internal perspectives that we have, looking foolish in how important this is, humility, and also the idea of really convincing yourself that the person you're talking to is intelligent, in this case. These conversations went on for hours. It's amazing. But mostly it was the ability to invest and believe in your imagination, believe in an imagined world, and this was very important. And then we took these, as a group we went out on the street and we set up this flip chart and we found strangers and we said, have you got something you can't solve for yourself rationally? And then we'd write up their question, this guy here we were working for, how can I approach this job interview differently? And he's really been struggling with it. He's said he's made so many job interviews, he's not getting the jobs. So it's a big thing for him. And I love this, it's like putting something at stake, putting something on the line. So we all got together as a group and we put these white glasses on, and we went into our world, our imagined world with this question. And we came back with some stories, basically. Some stories which we didn't really try and make the links to, but he did. He made the meanings for himself. And what was so wonderful is that he's making the arts, he's making the purpose, he's making the meaning. This is a woman, Irene, she lives on the local estate where we're doing it at the community centre. And her question was, what helps me from starting my own business? She's been wanting to do this for years. And it's so simple. She doesn't want her own business. But she's been battling with this for years. And she couldn't not see that. She couldn't see it until we came up with these stories of cows and fields and mountains and pumas and chickens and all these strange scenarios where we had interactions in these other worlds and we had interactions that were significant as experienced and we took knowledge from that. And she related to that in that way. So then the ultimate challenge for us as a group during that week. And this is sort of day four, really. So this is quite advanced now. We went to the City Hall in London. So we went to the mayor's office, really. And we said, can we work for you? Well, I arranged it beforehand, obviously. And this is the health team. Basically, the health team organised health policy. And we offered our services to them. OK, so we're the unconscious reasoning consultancy group. OK, I'm Helen. I'm Liz. And we work in the health team here for the mayor in London. And our job is to help him to make London a healthier place. It's not to think about hospitals and health services. It's about helping people be as healthy as they can. And to make London a place that it's easy to be healthy. So, do you have a question that you haven't been able to sort out rationally? Yeah. Our question is, if people know something is bad for their health, why do they carry on doing it? OK, I'll write that up. If people do something that's bad for them... If people know that something's bad for their health. Yeah. Why do they keep on doing it? And it's almost as though the question at knowledge is that just information is not enough. It's better than nothing. It's a beginning. But just the information doesn't seem to be quite enough. Yeah, I think that's always the case. Just because we know something's bad for our health doesn't mean... That would never be enough, you know what I mean? I think we all know lots of stuff. You can find out anything that you want on the internet, on YouTube. You can know anything that you want to know. We know that knowledge doesn't change behaviour. If you'd like to move your chair slightly back. Let's move our chairs back to the wall. Give us some space. OK, if you just find... This became about behaviour change, really. And that was an interesting question for us because it's an irrational question. It's about irrationality. Ultimately, we're not rational beings. We kid ourselves that we are, but we live in our unconscious. I think George Lakoff said actually, he was a psychologist. He said, our thinking, our reasoning is 98% unconscious. Our conscious minds are fairly small and limited. I mean, we can only apparently remember seven things. But unconsciously, we can remember an infinite amount of things. So we were pulling on these resources, really. And we came up with some really interesting answers for them. That they really valued, and what they valued most was witnessing us coming up with these answers. I mean, some of the stuff they knew before, but it gave it an element of truth for them. It was coming from people. It was coming from a place that they could actually see. So that's it, really. This is the last slide I'm going to show you. It's something from the book. It's on an elementary level. I took this into a school recently, and I put it up on the board, and it was an art class. And we were using the imagination productively. And then the maths teacher came in, and he stood at the back for the whole lesson trying to work this out. And then I said to him, did you work it out? And the brilliant thing was 90% of the kids knew the answer. And he said, no, no, I know it. I know it. You move all these ones down one. No, no, hang on, hang on. You add one to all of them, and no, no, hang on. And then the kids were just laughing at him. And that really showed me also that the idea of acquired knowledge, the idea of being an expert, we are all an expert in ourselves. We are all an expert in our imaginative worlds, and we can use these for lateral thinking, for creativity, for everything. I'll tell you the answer if you don't know it later. Thank you.


Poznači. Tako drža. Se počiš? Poželiš sva? Jih je vzout, da se Prof. Eveland Re, z Rutgerskjom universitetti, odreči, atakaj na elektronijske zvršenje z in 2D materijali. Ne znamen, da tako počišli, na 2-3... Ne bo. Na 1h. Tako, to je najbolj. Dobro, sem eksperimentalist in vznikam na 2-dimensične elektronice primarilj, z vrštih technikov, o kaj sem tukaj pravite. Vznikam tudi, dve lekture za tudi, vznikam vznikov, vznikam vznikov in teori, na Bluk diedve, that experimentalists like to think about. I think that since the discovery of graphene in 2005, it I think it is fair to say that it has revolutionized the way we think about materials. Since the discovery in 2005, there have been dozens new materials isolated or synthesized that are really two dimensional. Kaj je spesivalo na te dve materijale? Prvno, smo vse vse elektronici, vse vse kvazi partike, kaj je topologi in vse vse transporti, ki ne vse vse materijale, in vse partike vse fizika. Tako, zelo nekaj vse partike. Prvno je, ker vsi vse atomi nekaj vse vse, nekaj nekaj nekaj vse, but we can very easily manipulate their properties. So we can change, and this is, there's more and more of this coming everyday, that we can change the electronic properties at will without using any chemistry. So for example, you can stretch a piece of two dimensional material, like graphene or anything else, you can bend it, you can fold it, you can cut it, every time you get new electronic properties. zelo se pristim što je čest, da se je vsega zelo. Kaj je tega, da je však čest na pohledku, je, da se pohlede, da tvoje grafini ljudi nekaj začnje, in da se se kaj ne poznite, se počuče nekaj, kaj je se tukaj vsega zelo. In, da je ljudi ljudi ljudi ljudi ljudi, nekaj pa nekaj nekaj, nekaj, pristim. in najbolj, da sem pravda insulatora. In se jaz neskup, da sem vse superkondakter, ta je zelo vzostavljena. Daj je tvoje, da možete inžitati superkondaktivite. Sve in mnogo, je, da se neskup, inzulatora in neskup se je resenjala na nekaj vzobih, nekaj teznjah, za hodnje tk materijali. imaš tudi insulatične piste, in na dve strane imaš superkonductivne dome, je to izglednje, superkonductivne trazije, je to nekaj, da všeč imaš zelo, in imam tudi tudi tudi tukaj, kako je... Tukaj, moj pojnter je nekaj, za nekaj različ, je nekaj, baterije. Zdaj, sem spet baterije. Zdaj, bomo tudi tudi tudi. Zdaj, ko sem izgleda, je to, da se očetimo, o svoj tudi vrednjih materijali. Tudi o vsej elektroničnih prvniča, o vsej grafinji. Zdaj, v prviči vsej lektu zvom tudi elektroničnih prvniča, biasah kot naseljstva, zelo uštava i vse njič. No, to smo zdravili pozanjaj z magnetikom, zelo smo izgledaj na lanašneiate, začalje s��čno lanašneâte in vsebrand od njimlji, in vsebrand od njimlji, izgledaj več nam možno je dvečne emblantovice v disizu? Boj, nega sistersila je zelo v denominatoru. Tih je odprljene. OK, zelo, da se je začal. To je izvršen iz nekaj začeli vseh vseh, da je inštavno, da je vseh vseh inštavno, da je vseh vseh inštavno. Zato je to, da je vseh, različno vseh, da je vseh, različno vseh, da je vseh, da je vseh, da je vseh, today more graphite, the reason is people were very, after the atomic bomb people were trying to use atomic energy for peaceful purposes for atomic reactors, and what they needed is a moderator, so that Wallace Basses told him calculate the bands structure of graphite because that was a good candidate and he worked and then worked and failed, he was notay able to do this, so he said, ok as we as we usually do, I can't solve graphite, let me solve a simpler problem, let me take one layer of graphite, which we now call graphene, and let me solve the bandstructure of that. And there he succeeded. Actually it took another decade, twelve years, for a team from Rutgers to calculate a bandstructure of graphite. So this graphene, this layer was pretty much forgotten over the decades, nobody thought about it. da vsi všeč nekaj sej teoriči dobrali, ostali in vseč jazovil in vseč loli. V 1943 godine Seminov skupilšnje za vsečnjezno vsečnjezna za tredimentinje lahko in v 87-ji dan, Danken, Haldane skupilšnje za modem of krandom, in izgleda vsečnj, in zelo včasno je svoj, boješnje vsečnjezna za taj svoj, in nič nekaj stajili, da se to je na vse vsi načo, nekaj nekaj jaz nekaj skupite v labu. A jo da?  Zato neka je dela, da če je način način izgledajši, je več brav, da se je izgledajši na 3. način in prišlojiti način način način. Način način nekaj nekaj nekaj magnet, nekaj nekaj superflujt, nekaj nekaj superkonduktor. 2-dimensional crystal because there is no long-range order. And here is an illustration of why that is. What I have here is 400 carbon atoms, and they're thrown into a cubical box, and they're numerically heated up to 2,000 degrees Kelvin, and let's watch what happens. You see the atoms jiggling around. Every once in a while, they will grab a neighbor and form a chain, and if you watch long enough, they even form a ball, a bucky ball, which is kind of stable, and this can go on forever. It can go on and on and on, and no matter how you even may be able to do a nano tube, but no matter how long you wait, you will never get a 2-dimensional surface because fluctuations out of the plane are too cheap, and the fluctuations are going to destroy the long-range order. In 2004, Gaiman Novoselov from Manchester announced that they were able to isolate 2-dimensional atomic crystals. People did not believe them. In fact, they were not able to publish their work because people said, you can't do that, you must be lying, you must be cheating. So they got very nervous, they invited everybody in the field to come to their lab to teach them how to do this. So they were able to isolate graphene, niobium-dyselonite, boronitride, et cetera, about five different 2-dimensional materials. So what was the trick? So they thought, okay, you cannot have long-range order in two dimensions, can we cheat nature? So you have layered materials, like graphite or transitional metal-diacalcogenite that have very strong in-plane bonds but very weak van der Waals bonds in the third direction. So you get layers, and it's very easy to exfoliate them. So their idea was, okay, let's play like a conjurer trick. We pull one card out of the deck, and let's see what happens. So this is what they did. In fact, if you write with a pencil, we've been writing with pencils, I think since the 16th century when the graphite was first discovered, the pencil was first made. And every time you write, you bring pencil to paper, in the debris that is left behind, there will be graphene. And we've been making graphene for centuries, except nobody knew. And what's the reason that nobody knew? The reason is that it's impossible to see a layer that is only one atom thick. There's just no contrast. You don't have the tools to see them. So this was the well-kept secret for all this century until a gymen of Novaselos completely accidentally tripped over the following. We said, OK, we're gonna take some scotch tape and just put it on a substrate. And they had sitting in the lab a very old wafer, a wafer covered with 300 nanometer of silicon dioxide. This used to be used in the 80s in the semiconductor industry. And the reason this has 300 nanometers of silicon dioxide, nowadays this is totally obsolete. So they just had this lying on the shelf and they put their graphite. They just wrote with a pencil, if you like, on top of it. Now, the reason 300 nanometers is when you shine light of it on this wafer, you have reflection from the top layer and reflection from the interface with the silicon. And there is a destructive interference between the two rays at green light. That makes it so that any piece of dust will appear, will be visible because you change the phase of the interference. And the reason they had to do it this way because in those days you inspected the wafer manually just by eye. OK, so there are these extension bands. This is wavelength versus thickness of this layer and you see everywhere where you have dark you're going to get, you're going to be able to visualize dust or anything else. So if you work at 500 nanometers wavelength, which is green light, where our eye is most sensitive, 300 nanometers is a sweet spot. So they had this and they put the graphene on top and this is what they saw. So with the 300 nanometer oxide they immediately saw this is single monolayer, bilayer, trilayer. I see the step in atomic force microscopy. If they had 200 nanometers of oxide and white light they would have seen nothing and 300 nanometers of oxide and white light it would have been much less of a contrast. So you see there was really serendipity at play here. So how do we make graphene in the lab today? Let's see if this works. Take a Scotch tape and gently lay it down on a flat surface. Next, take clean metal tweezers and pick a thin graphite flake and then place this gently onto the Scotch tape. Next, fold the Scotch tape at the edge of the graphite flake. Peel it off gently and do this step several times until you obtain a nearly transparent region on the Scotch tape. After this, take a clean silicon wafer to transfer the Scotch tape graphene onto the wafer. Use plastic tweezers and gently rub the area of the Scotch tape where graphene may potentially be. Slowly peel off the Scotch tape so as not to break any potential graphene sheets. Use an optical microscope to view and find graphene. Graphene appears as a purple spot on the screen. The center of the screen is multi-layer graphene and at the lower right corner of the screen is single-layer graphene. This is how we do it. Nowadays, there are techniques where chemical vapor deposition where you can grow huge areas like a whole wall full of graphene but those are not perfect. They have dislocations, they have grain boundaries, but this technique by exfoliation is the best sample. When you want to learn about fundamental physics, this is the technique that you use. Still today. Just a few properties of graphene so you must have heard that it's the strongest material known. How was this measured? This was the group, the Manchester group. They took a sheet of graphene which was about half a micron, about actually five microns long. They founded it with copper nanoparticles and they measured how much it deflected at the end. They found that it deflected by what nanometer you immediately can calculate that the Young's modulus is about two terapascals. To give you an idea what this means if I had a piece of paper here and it was as large as this room, if I put all of you on this piece of paper, if it were graphene, it will sag by about one centimeter. This is what two terapascals means. By comparison to other materials, here are all the materials that we know. Up here we have ceramics. Steel is somewhere here too and if you put graphene on the same sheet, it's stronger than anything we know. That is one of its unusual properties, remarkable properties. Another is optical properties. This is an optical microscope where you're looking at the reflections through graphene, so this is no graphene, one monolayer graphene absorbs 2.3 percent of light, two monolayers double that. In fact, because of the electronic properties that we're going to hear about, the amount, the transmission is one minus alpha, alpha here is the QED, fine structure constant, this is the only thing that enters into the physics of graphene and pi, so it's 97 percent for one layer, it's 2 alpha pi for two layers and so on and so forth. This is when it's a charge neutrality, when you gate graphene and you put in electrons or holes, so you can actually change, for example, this is a gate voltage here, so this is charge neutrality, so the transmission, it's almost completely transparent, you put 50 or 30 volts on it, it becomes dark, so you can use that, for example, for screens and so on and so forth. One last property that I'm going to mention is it has, it's sensitive to single molecules, so for example, if you measure the change in the hole resistance when you add sodium or ammonia or carbon monoxide, every molecule that comes in gives you a step in the resistance, so you can actually measure single molecule, very sensitive nose. One other thing that is very important today is that it's completely impermeable, you can put a pressure gradient of one atmosphere of graphene, of helium, for example, not a single helium atom will go through, perfectly permeable, even though it's one monolayer thick. So since the discovery there were many new two-dimensional material that discovered about 40 of them, transitional metal dicalcogenate for phosphorine family, monocalcogenites here and so on and so forth, and they each have different properties, superconducting, insulating, semiconductor, and so on, and what's even more, now it has become an industry, you can just stack them one on top of each other and you can put various properties so you can design your material basically without any chemistry. So these kinds of stacks, if you try to actually synthesize them chemically, many or most of them are not stable, but doing it this way these are, of course, they will probably metastable, but they're stable enough to make a device out of them and to examine their properties. So here is, for example, how we do them in our lab, you pick up a graphene piece with boronitride, you have a polymer here, which we call PDMS, and you just press it onto a substrate and then you can put another boronitride layer on top and this is what it looks like in an optical microscope. So this is graphene boronitride, boronitride graphene and on top of that boronitride is the same kind of material that was used in order to discover the superconductivity and the twisted layers and this is a TEM image and you see how beautiful, perfect they are. The boronitride layers are here, graphene is here OK, so let's go, let's talk about carbon now. So carbon has six valence electrons, has four valence electrons, six total electrons and when it makes a chemical bond there's two ways it can make a chemical bond. One is the SP3 where the four valence electrons hybridize together and you form a symmetric structure which is a tetrahedron and this is gives rise to diamond basically. It's a very strong insulator, insulating material. Now the other kind of bond that graphene can make that carbon can make is SP2 where we have we have three of the valence electrons hybridized into and they use into these, to form these sigma bonds these are flat bonds separated 120 degrees from each other and there's one pi orbital that sticks out. This is the SP2 hybridization and this gives rise to graphite which looks like this and of course a single layer would be graphene. What is actually very interesting, I mean when you ask your girlfriend to marry you some people give her a diamond because there's this myth that diamonds are forever but in fact diamond is a metastable phase of carbon, the stable phase of carbon is graphite. If you look here graphite so this is pressure versus temperature so this is where room ambient conditions are the stable form is graphite. So don't tell it to your girlfriend eventually the ring will turn into soot but she can wait that it's gonna take many years. Now carbon is the only element on the periodic table that where SP2 is the ground state all the other elements all the other elements in the fourth column the stable form is SP3. So people are trying very very hard to make silicon that's called silicon germanine but it's very hard because they don't want to do that and the reason is carbon is because of the ratio of the size of the orbits because it's only in the first level that your valence electrons are and their coulomb energy is strongest whereas in the lower elements silicon and germanium etc. atom is larger the p orbitals are further out and it pays if you do the calculations it really pays to be SP3 only carbon has a ground state of SP2 so only carbon can create something like graphene except if we try hard as you will see later Okay so SP2 carbon allotrop there are several forms so it's a very flexible kind of structure because it's two dimensional and it's bound in the third direction with another layer by very weak van der Waals forces so this is a zero dimensional form this is a bucking ball discovered in 1985 actually it was discovered by astronomers 1996 Nobel Prize the second form is the carbon nanotube this is the one dimensional form discovered in 1991 no Nobel and it's the reason there is no Nobel for this is because there are too many people fighting each other and whenever that happens there is no Nobel because they can't make up their minds and the third one was two dimensional Nobel in 2010 and this is graphene and of course three dimensional is graphite okay now we're going to the next topic which is the electronic properties the band structure now I'm going to just do a quick reminder of tight binding because the tight binding gives a very very good it's a very very good approximation to the actual band structure of graphite of graphene okay so if you have a periodic potential in red here we have the atomic orbitals which sit on the atoms and then if you have phi's are the eigenstates of the isolated atoms and now if you have a little bit of overlap between the orbitals and if it's small enough your Hamiltonian is the original Hamiltonian plus the perturbation you can do perturbation theory so this is the new Hamiltonian new wave function and we can just expand in this correction delta u so tight binding works very well when you have small overlaps so the way this works is okay if you have a periodic structure and in order to have a periodic structure you have to have a Bravais lattice and this is a real kicker here and as you will see in a moment if you have a Bravais lattice which means that you have a periodic structure you can write a block function block function is a good solution for your Hamiltonian so you write it down like this it's a plane wave multiplied by something that is periodic and this is the atomic wave function on each one of the atoms and then okay we have the block wave function we plug it into the Hamiltonian so these are the conditions the wave function has to satisfy normalization number one it has to be at eigenstate of the Hamiltonian number two and then you just do some algebra and you find a solution it's as simple as that although the algebra can be pretty involved but there's only these three steps and then you write you find a solution in terms of the transfer or hopping integral which is these are nearest neighbor and we call it tij and also in terms of the overlaps between adjacent wave functions and this is another way of writing down the Hamiltonian with raising and lowering operator but it's the same thing but the reason I'm writing it like this is because it has explicitly here the transfer integrals so so so so when you do tight binding for very simple periodic metal like gold or silver you usually get a very simple band structure that can be approximated but it's basically quadratic in a momentum and if whenever your energy is quadratic in a momentum you completely say that must be momentum square whatever is the numerator here must be a mass so we define an effective mass which is absolutely nothing to do with the actual mass of the electron it's just a way of saying that the energy is proportional to the square of the momentum so we get something that typically looks like this this is a parabola wave function these are equi energy surfaces now how is graphene different now the graphene is different because honey comb lattice it's not a bravel lattice the games that I've done here don't work for when you don't have a bravel lattice so when you don't have a bravel lattice you get all sorts lots of lots of interference and your band structure looks like a mess looks like this and these are the equi energy planes so you get a very unconventional dispersion by the way this is exactly the dispersion that Wallace got except that it was not in three dimensions but his solution was absolutely correct even in today's terms so now what I'm going to do I'm going to walk you a little bit through how we get the solution and I'm going to walk you through the quasi particles that corresponds to low energy excitation for graphene but they have weird and interesting properties those graphene quasi particles ok so we start so there's only three ingredients that go into the unusual band structure of graphene really only three the fact that it's two dimensional the fact that it's a honey comb lattice which means that it's non brave and the fact that we have identical units on the two sub lattices now what do I mean by two sub lattices notice that a brave lattice is one is when you move no matter where you move how many lattice spacing you move your environment is exactly the same but here you see immediately we have two group it's bipartite we have two groups of atoms I can color it red and green the green atoms have a red neighbor down south the red atoms have a green neighbor up north so this is not a brave lattice it's two interpenetrating triangular lattices which are brave so what we have to do we have to write a wave function two wave functions one for the green atoms and one for the red atoms and the total wave function will be a linear combination of the two so here are just some concepts to give you some idea don't get too hung up on this I'm defining here the lattice constant A so that's the lattice constant for graphen is 2.46 angstroms this is the first Brillouin zone that looks like it's a hexagon these are the reciprocal lattice vector and there are special points in the Brillouin zone these are the k-points that we're going to talk about a lot and one k-point is at 4 pi over 3a this one the m-points in between the 2 here and the gamma point is the center of the Brillouin zone so we're going to mention these a few times so because we have two wave functions the wave function for the electrons in graphene is a linear combination of the two so it can be written as a linear combination of the wave function on the A sub lattice and one on the B sub lattice so green sub lattice red sub lattice and you can write down the prefactor here this looks exactly like a spinner it has two components because we have two difference of lattice each component corresponds to the part of the wave function that it's on the green or on the red sub lattice so immediately you see we have a new degree of freedom this is like and it resembles spin up and spin down for a spinner but instead of acting on the spin we're going to be acting on the sub lattice degree of freedom which we call now pseudo spin it's not a real spin, it's like a spin we call it pseudo spin ok so I'm going to do a little bit of the derivations here because there's a few concepts that I want to bring home so the Hamiltonian of course is a 2 by 2 Hamiltonian and on the diagonal here we have the self energies here on the a sub lattice on the b sub lattice here and the off diagonal here we have the phase which is basically the sums of the phases of the nearest neighbors e to the ik delta j sum of all these ok so these are the things that go in now for graphene epsilon b and sorry this should be epsilon a this shouldn't be a b ok epsilon b and epsilon a are equal and we call them epsilon zero and this really simplifies the algebra enormously and by the end of the day we get a constitutive equation like this where the energy has two where we have two solutions which I'm going to draw in a moment but notice that it depends on two things one it depends on the hopping integral t and two it depends on the phase here so it depends crucially on two things the two most important things are a the geometry which comes in through f here because it is triangular geometry and b it's t here which is the hopping integral ok now here is a note of caution if we have different species of the two sub lattices the solutions are extremely complicated and most importantly you will get a gap at the fermi energy you will get a gap at charge neutrality it's going to be an insulator so one example is for example boron nitride where it's identical to graphene instead of having carbon everywhere one sub lattice has boron the other sub lattice has nitrogen and that has a huge gap has a 6 electron volts gap so the best insulator we know because because you avoid this crossing here which you're going to see in a moment so this is the solution I'm writing down the solution and it's really very simple algebra I strongly recommend that you do this as a homework and these are the two solutions we have an antibonding and a bonding solution these are for the plus and for the minus and you see they cross here this is what we call the Dirac points they cross at these points now if you look on the brilloenzo this is the K and K prime so these are the two points but of course this has to be a two dimensional structure so we have six of these K points so you see we have six of these paper this is what the three dimensional image of the mass structure looks like but what we're going to be interested in is the low energy properties so we zoom into this point here the crossing what we call the Dirac point and this is what it looks like now we have six points here I only draw two why do I only draw two why should I not draw all of them it has to do with the fact that that all the other guys are connected to either K or K prime by reciprocal lattice vector so the physics is identical so only two matter all the other ones are going to just repeat the same physics because you can move from one to the other by adding a reciprocal lattice vector now one very important thing you probably learned in your first course in condense math in solid state that if you have bands that intersect you have level repulsion you open a gap and it happens so why isn't anybody asking me how come this survives now the reason it survives is that it's protected by three symmetries you have to the symmetries by which it is protectors is time reversal inversion and C3 rotation by 120 degrees so you have to break at least two of them to open a gap very very difficult to gap out graphene which is both a curse and a blessing ok so those the rock points are very very stable I mean you can stretch the thing you can bend the thing they move around in case space but they don't open a gap until you do something dramatic no no ok very good question this is only nearest neighbor now when you include next nearest neighbor now you see we have electron hole symmetry what happens if you include next nearest neighbors you're going to break the electron hole symmetry not open a gap next nearest neighbor doesn't do anything to the symmetries so you introduce next nearest neighbor you're going to get instead of it being beautiful and symmetric this is going to be a little shallower than this but really qualitatively nothing new happens ok so some nomenclature so it charge neutrality the Fermi energy sits exactly at the the rock points in the upper band is called you have conduction electrons the lower bands we have valence is the valence band so conduction and valence band as usual with semiconductor it's just that there's no gap ok a little bit more of formalism and don't get too hung up on it there's a few points that I would like to make so first of all we go near the k points and then we do a linear expansion so the k, the 2k points here are psi, psi is an index these are called valleys so the psi is an index for valleys so plus 1 for k minus 1 for minus k and then the position of 4pi over 3a and 0 on the 2 sides here right? if you expand in small momentum term here so so we define k as the momentum relative to this the rock point to this k points here we define little k and this is by how much we deviate from this point so we deviate a little bit around here so we get what we call what we will now call the momentum relative to the rock points so these are the momentum operator here now I'm doing the linear expansion for this phase here and the Hamiltonian, so if you put in these approximations here you get an approximate Hamiltonian that looks like this and the prefactor here vf, which is we call the Fermi energy is proportional to the overlap integral times the lattice spacing with some factors here and this number here is about 10 to the 6 meters per second it's a velocity it's a velocity of the quasi particle as you see in a moment but it is about 300 times smaller for example in the speed of light you will see in a moment why I'm mentioning that ok, so this is the Hamiltonian when you have close to the rock point it has this form here so it will have a plus here in the k point in the k prime point and so this is exactly a Dirac-like equation with eigenstates are the projection of the wave function on sublates A sublates B so this is again our Hamiltonian as I wrote it before in shorthand notation I can replace I can write px times sigma x and py times sigma y so I can write it in a shorthand notation where the sigmas are the matrices so I can write it in terms of poly matrices so I have a very nice compact notation so the bottom line the Hamiltonian is equal to the Fermi velocity times the projection of the momentum on this pseudo spin sigma is a poly matrix but remember it operates on the sublates degree of freedom not on spin we haven't talked about spin at all here so this is a Hamiltonian extremely simple this is exactly what we call the Dirac-bile Hamiltonian which is for ultra relativistic particle that are massless same Hamiltonian as for neutrinos except that this is in two dimensions and except vf here replaces the speed of light for neutrinos you will not have speed of light instead of vf ok so poly matrices they operate on the sublates degree of freedom so if we take into account the k-points and the two k-points then instead of having a two component wave function we have a four component wave function and we can just the Hamiltonian breaks down into two blocks one for k and the other for k prime what's important to notice and this is very very important is that Hamiltonian for the k point is vf sigma dot p whereas for k prime it's vf sigma star dot p this is the time reversal brother of the k so the physics in the k prime valley is time reversal brother of the physics in k so whatever if you go like this in the k valley the electron in the k prime valley is going the other way so these are related by time inversion symmetry now the third point that I want to make is no we can solve for the Hamiltonian very easy it's a 2 by 2 Hamiltonian you can solve for the energy spectrum and you can solve for the wave function and the energy spectrum is extremely simple it's vf times p or you can write it as h bar k and s here is the band index so it's going to be positive in the electron in the top band and s is negative in the bottom band here and the wave function looks like it again s it changes side for electrons and for holes so you have this is a plane wave multiplied by a spinner now phi here is the polar angle it's just the ratio the arc tanges of p y over p x it's the polar angle so what we see here immediately this dispersion is no longer p squared over 2 m it's actually vf times p this is exactly the dispersion that we have for photons exactly the dispersion that we think we have for neutrinos these are massless particles mass is zero mass is linear in momentum not quadratic very important so it is like photons except these are very slow ones they move 300 times slower than photons or neutrinos now this two component vag spinner it's a pseudo spin vector and notice phi appears here when s is plus one the pseudo spin is parallel to the momentum we have e to the i phi one here when s is negative it's antiparallel to the momentum and you're going to see in a moment what that means and number four absence of backscattering within a dirac cone so this is our wave vector if you take if you take the projection of the wave vector in direction zero so this is basically the angular scattering probability angular scattering probability around a circle you take the projection of psi at angle zero onto projection of psi at angle phi the square of that is cosine square phi over two what you see immediately that it's zero there's absolutely no backscattering at when phi is equal zero so under pseudo spin conservation that's what this means backscattering with one valley is suppressed there's no backscattering with one valley so an electron that moves in one part of the cone cannot scatter back to the other part of the cone no backscattering within a valley so this is very important for transport properties and number five is the helicity so we've seen that Hamiltonian can be written like this sigma dot p now you can pull out actually the magnitude of the momentum this is sigma dot n this is known as the helicity operator is the projection of the spin onto the direction of the momentum it's called helicity finite mass so you see that this is a good quantum number so the projection of the pseudo spin on the direction of on the momentum or on k is a good quantum number it cannot change so helicity is a conserved quantity and we can have in conduction band the helicity is plus one so it goes let's say clockwise in the valence band it's minus one they go the other way and here is an illustration of that so in conduction band p and pseudo spin are parallel to each other in the valence band they're anti-parallel to each other now in the other cone everything is reversed because of the time reversal symmetry so if you have because helicity is conserved in the other cone everything is opposite we have no backscattering between cones so what does this all mean so here are the two cones this is the Hamiltonian in this k and this is the time reverse Hamiltonian in this k conserved helicity and you see one we have plus helicity in the k cone minus helicity in the k prime cone what this mean that there is no backscattering between the two but we also cannot backscatter because because you cannot backscatter within one cone we just did that so the bottom line it's no backscattering which mean you send an electron in your sample it can't go back it just that means that you can have very large mobility why is there what oh it's a good quantum number this is helicity so if an operator commutes with your Hamiltonian that means that you have a common basis vector and that means that corresponding observable is conserved unless you disturb it somehow ok so this brings us to climb tunneling now here I have a barrier that you can do an electrostatic barrier I have an electron this is graphene and I am applying a voltage here ok so it causes a barrier now one thing that maybe I didn't emphasize is that the Dirac point rides on top of the external potential so the external potential here is this is flat here so Dirac point is here here the Dirac I apply a voltage so the Dirac point is here now notice what's going on so I bring this is the Fermi energy I'm bringing an electron it's moving to the right that means it's moving on this branch here it's moving to the right now it's coming under the barrier now it's no longer an electron it's a hole there's lots of places for it so it's not it doesn't have to go back but it also cannot go back because there's no back scattering it does that by turning into a hole and then it comes out again so it is as if this thing completely didn't exist it's completely transparent so this is I tried to do this little animation hole, it's completely insensitive to electrostatic barriers this is called client handling it used to be called the client paradox how come these massless chiral particle can just go through barriers it's a paradox it's this it has to do with having basically the conduction and valence than touching so what are the consequences we cannot have electrostatic confinement we cannot use electrostatic to do anything to the electrons in graphene they do whatever they want can't control them with electric fields so you can't do all the things that we know and love like make quantum dots which make transistors you can't guide them and so on and so forth however I told you that there's no back scattering but that you could have side scattering and the sides so now this is transmission probability as a function of angle of incidence so zero if you come ahead on the transmission is absolutely one but if you go at one angle and it'll depend you have regions where there is almost no transmission and the red and green depend on the energy on the density of your carriers I'm going to come to the last point and that is the berry phase so this is a paper by Berry in 1984 so if you have a Hamiltonian and you very slowly change something in the eigenstate and very slowly changing the adiabatic approximation that tells you that the wave function is going to follow is always going to be an eigenstate of the Hamiltonian so you take your Hamiltonian through some sort of a circle you come back to the same point the Hamiltonian is the same the wave function will have changed by a phase and people knew that forever since quantum mechanic was invented phases don't matter in quantum mechanics let's forget about it what Berry showed is that this phase carries the information about the trajectory that you went on and phases can be seen in quantum mechanic when you have interference effect so it's not completely invisible so this is what Berry said and he showed an example how to calculate the Berry phase by how much does the phase change of the wave function change when the Hamiltonians come back to the same spot so you go along a circle you have a parameter lambda equals 0 that your wave function depends on you go on a circle and you come to lambda equals 1 so you increment it continuously and when you come and the circle at lambda equals to 1 and then you calculate the Berry phase like this is the imaginary part of the integral over on this loop of your integral over lambda u lambda d by d lambda you take the derivative of your wave function with respect to lambda and I'm going to show you that if you do this exercise with the wave function for graph this is pretty neat so what does the Berry phase mean when the phase of your wave function changes that means that something in the geometry it measures something in the geometry or topology of your of your environment of space take for example a Mobius bed of course there is that the topology is not simple and if you follow g for example I am going around g is out here I am not seeing it and then it is going here and then it is going to appear again I have to go twice around the circle for g to show up on the circle tells me something about topology of space another very nice example is parallel parallel transport let's say that you have a car and with a little handle pointing sideways and you are going along a geodetic so I am coming down here my car is pointing this way I am doing parallel transport so now I am going to move parallel to myself and then I am going parallel to myself like this you see it is always pointing in the same direction the car knows it is a weird car and I am coming back to the exact same point but now the nose is pointing in different direction this is the very face and it measures the curvature of the space on flat space you get zero it comes back to exact space but this is a way to measure the curvature of your space in optical fiber this is a very neat thing you send a polarized light in optical fiber you twist the fiber around the polarization is going to change direction is going to change and the dirac belt is amazing but I don't have time to do it I can illustrate it with my hand but I am not always successful in the break maybe I will show you ok so if you do this thing for the wave functioning graphene it is pretty straight forward you just do this integral you define lambda as 2 pi theta over 2 pi and you take lambda from zero from zero to one you take this integral and you end up with pi so the very face of graphene for the quasi particle graphene is pi and that has to do with the singularity of the dirac point it's measure the topology of space we have a singularity of the dirac point this is what it measures and as a result it has all sorts of weird consequences which are seen in quantum whole effect and in landau levels ok ok if you want you can do this as a homework exercise ok so I think I am pretty much done with my time right for the first part I have 3 more minutes ok if I do 3 more minutes here I am or if you are tired we can do it after the break let's do it after the break


Daily Tech News Show is made possible by its listeners, thanks to all of you, including James C. Smith, Miranda Janell, and Justin Zellers. Coming up on DTNS, should Apple make Siri easier to activate? Why Airbnb price transparency isn't great for everybody, and how cosmic rays cause software errors. This is the Daily Tech News for Monday, November 7th, 2022, in Los Angeles, I'm Tom Merritt. And from Studio Redwood, I'm Sarah Lane. From the far-to-warm New York City, I'm I.S. Actor. And the show's producer, Roger Chen. Oh, my friends, we are going to solve the mysteries of the universe and why your software just suddenly makes weird things happen. But first, the quick hits. Apple announced it anticipates shipping fewer iPhone 14 Pro and 14 Pro Max units due to COVID-19 restrictions at the primary Foxconn factory in Zhengzhou, China. China ordered a one-week lockdown in the area starting November 2nd. Apple says the factory where many iPhones are assembled, quote, is currently operating at significantly reduced capacity, end quote. Apple advises that customers will experience longer wait times to receive their new products. Shipping is now estimated to take three to four weeks from order. Over the weekend, several people noticed the Twitter app update notes indicating that the revised version of Twitter's blue subscription service had launched for $7.99 a month and included verification. However, product manager Esther Crawford from Twitter noted on Twitter, the new blue isn't live yet. The sprint to our launch continues, but some folks may see us making updates because we are testing and pushing changes in real time. So you could never actually subscribe to it. She continued, the Twitter team is legendary, salute emoji, new blue coming soon. So no new Twitter blue just yet, but it sounds like you might get it by the end of the week. In other Twitter news, Elon Musk said that any Twitter handles engaging in impersonation without clearly specifying parity will be permanently suspended. Previously, Twitter issued a warning before such suspensions. China's second biggest chip manufacturer, Wahong Semiconductor, received regulatory approval for an initial public offering on Shanghai's star market, hoping to raise $18 million in the next offering, which is about 2.5 billion US dollars, which will be used to invest in a new chip fab and upgrade an existing one both in the city of Wushan. TrendForce estimates the company holds a 3.2% market share in the global foundry market, making most of its revenue on mature technology, mostly based on a 55 rather nanometer process. Now that star market is a stock market in Shanghai, very different than the one you find on the hub in the causeway in Boston. Totally different star markets. LiDAR is a key technology used in autonomous driving. Over the years, many LiDAR startups come onto the market to try to get a piece of the driver assistance pie. Now we're seeing the industry consolidate. Two LiDAR companies, Auster and Velodyne, have agreed to merge according to a November 4th agreement. Neither company has been able to turn a profit, but they hope that by combining their not profit, they can create scale to drive profitable and sustainable revenue growth. Over the last year, both companies acquired other LiDAR startups. Auster acquired Sense Photonix in 2021 and earlier this year, Velodyne acquired Blue City AI. MessagingApp Telegram added video messaging transcription now available to its Telegram premium users. Free users also get new features. Topics and groups will let groups with over 200 members create separate spaces that work like individual chats with discrete notifications. It also added collectable usernames which can be purchased and sold, secured on the Taun Ton blockchain. They can be fewer than five characters long and function like regular usernames and search and links. In other encrypted messaging news, Signal also added a feature that many are delighted by, but some annoyed by. It added the ability to share ephemeral messages, videos and text. They expire in 24 hours. Kind of how ephemeral messaging works on other platforms. Something that Signal is very creatively calling Signal Stories. It's available on iOS and Android now and coming to the desktop soon. Now, don't worry if you're not into it. You can turn off viewing stories in your settings. Yeah, but you know, give it a shot. Let's see what people do encrypted. And that's the quick hits. Alright, Apple's doing something that may or may not be a good idea. Yeah, so Apple historically arrives a little later to a certain type of technology making up being late to market with its own polish within an emerging category. You could think of the iPod, not the first MP3 player. iPhone wasn't the first smartphone, but Apple was uncharacteristically early when it came to virtual assistance on smart devices. Siri came out in 2011 with the iPhone 4S, three years ahead of Amazon's voice assistant. And certainly there have been others since then. Being so early, however, its wake word set the tone for the industry with the hey wake word, in this case Siri, approach being used by Microsoft's and Google's assistants as well. Samsung broke the mold with their daring high Bixby implementation. That was wild. But now Bloomberg's Mark Gurman reports that Apple began an initiative to change the wake word for its smart assistant to just calling out Siri dropping the need to say hey before the name. Gurman describes this as a technical challenge that required a lot of AI training and underlying engineering work. The new wake word approach is in testing with employees to gather training data. The company reportedly plans to roll out the switch early next year, but Gurman says this could also slip into 2024. Yeah, this also comes as Apple plans to integrate Siri more deeply into third party apps. The idea being to improve the ways that Siri can understand a variety of requests and perform a correct course of action if it can connect deeper into Apple's app ecosystem. Now, we will get to the technical challenge because I think that's interesting here. But the first reaction I had when I heard this story was my Siri has been going off accidentally more often lately, and I feel like dropping the hey part would make it go off even more, right? Like, hey Siri is a lot easier, is a lot harder to accidentally say than just Siri, as witnessed by the fact that we never say I'll exa all in one go because we don't want to set off everyone's Amazon Echoes who's listening to us. I've gotten a lot of false reactions from my iPad when I was just saying the word serious. So I'm not even saying hey anything. I would try to look at my script and saying what am I saying that's close? Serious. So if Apple's going to do this and they figure out a way to have their machines understand what word you're actually saying. That'd be a great improvement, but if this gets any worse, I mean that would be, I think a real problem because Siri is still collectively thought of as, I wouldn't say it's a big of a joke as Bixby, but it's way behind considering how much Google and Amazon have leapfrogged them. I mean, I don't know. I think it's gotten a lot better since its early days back before there were really voice assistants in general. I definitely set off my Amazon assistant for all sorts of reasons. In fact, sometimes it happens during the show where I'm like, I didn't say anything that even started with the literary. Like what are you doing? My mom, when I was visiting her recently, she's got an Apple watch and we were talking amongst ourselves and her watch kept going off because we were triggering that somehow. And we just kept laughing and not really understanding what was going on. I think that that is sometimes a ha-ha situation, sometimes an annoyance and sometimes worse when you actually trigger something where you're like, oh man, this has got to stop. Where can I give more input on the fact that whatever I said, the next time I say that, do not do this again? And I think that's where I would like to see a little bit more some programming efforts because right now it's like, you just get kind of annoyed and stay quiet for a second and then everything goes off and your life continues. Yeah, and I'm willing to entertain the possibility that reducing it to Siri and all the work they're doing to make that work will actually be a net improvement. That they're going to hone in on that and make it only active when you really do say Siri. How many times have I said hey, Sarah and then complained that Siri not only launched but transcribed me saying hey, Sarah? Like it knew I said Sarah somehow, but then also thought I said Siri? I'm on board. Because there's two different systems going, right? And one was apparently better than the other. This means that there's a lot more advancements in their chips and their actual machine learning technologies because if the home pod gets smarter, the watch is smarter, everything's getting smarter, that means these chips are getting more and more like, just great. So that's the thing about the technical side on it. That also kind of speaks to the fact that when I first saw maybe this wouldn't roll out until 2024, I was like, really? I mean, how hard is it? Clearly there's more going on besides just saying, oh, let's delete the word hey. It's easy to make it work badly. It's hard to make it work well. Well, this is an error that we kind of know why it happens. Have you ever had a weird computer error and thought that the only explanation could be ghosts or maybe cosmic rays? Well, there may be something to that second one. Chris Baraniak wrote an article for BBC Future last month called The Computer Errors from Outer Space. His article started with a story about a security researcher named Marie Moe, whose pacemaker suffered a glitch because of some oddly corrupted data that she believed was probably corrupted by cosmic rays when she was in an airplane. Now, that may sound far out, but particles from the sun and elsewhere in the universe constantly rain down on Earth. Some of them like neutrinos pass right through everything without incident. Some like photons provide life-giving energy to plants and animals. And some, like stray protons or neutrons, may in rare cases cause what's called a single event upset. These are radiation-induced soft errors caused by the impact of energetic particles on circuits. One example would be an errant neutron passes through a chip and disrupts the electrical charge to flip a 1 to a 0. Flipped bits were diagnosed as the cause of Moe's pacemaker issue, though whether they were flipped by cosmic rays or not is impossible to tell. Yeah, it's hard to prove. Single event upsets are exceedingly rare and they don't leave a trace. An error caused by an errant cosmic ray is indistinguishable from just a software glitch or a memory bug or normal wear and tear on an old piece of equipment. And even if you can distinguish particle-induced effects, they are so rare it would be hard to get a representative sample size to do any kind of significant study. One of the largest samples collected is from Mozilla, whose engineer Travis Long noted back in April this year that it routinely sees unexplained errors in telemetry data that correspond to flipped bits. They can tell that it's flipped bits and Long noted that a recent bug associated with such errors correlated with a geomagnetic storm. There was also a study of satellites published in 2020 that showed the data errors in orbiting satellites happened in much larger numbers when satellites passed through something called the South Atlantic anomaly where there is increased cosmic radiation. These are correlative though, not causative. While it's hard to prove if it did happen, you can prove that it's possible. Paolo Rec at Trento University in Italy has conducted lab experiments where they fired neutrons at electronics and induced errors. They are using the data to develop improved autonomous car algorithms to be able to detect and adapt to such errors. Yeah, you can use the particles to create an error. You just can't prove if a particular error was because of a particle, I guess, unless you were the one shooting the particle at it. So what can you do with this information? On the one hand, be aware because the occurrence may be increasing. There are so many more chips being used at any given moment that there is just more of a chance for it to happen because there's more chances out there. There's more chips, therefore more chances. And as chips are getting smaller, we're talking about one and two nanometer processes, it's easier for subatomic particles to affect them because the particles are the same size. You also might check space weather. Periods of increased solar activity raise the amount of particles hitting the Earth. For instance, spaceweather.com reported a solar flare on November 7th that interrupted shortwave radio temporarily over Australia and New Zealand. But the number of incidents is still exceedingly rare and almost always is compensated for by error checking and software. Data centers can protect themselves by being geographically diverse and critical equipment like computers in air and spacecraft are hardened against interference.  So you don't know how they're protecting them. Those are kind of trade secrets. So it'd be really hard and probably expensive to do this on your own, which is why they say, for a data center, just make sure you've got data centers in multiple places if you're a big company like that. Reading articles about this and seeing that they're using this for cars and their ability to essentially identify whether they're seeing an object or a person or not. If a flip bit could cause that kind of scary confusion for a computer, that would be like a terrifying real-life example since this self-driving car thing is supposed to be happening, not happening. You guys have been covering that for a long time. So the real-world stuff, hopefully, those applications are hardened very, very much to avoid any kind of catastrophes. It's not hardened at least to error corrected, right? The car example is one of those stories where it's like, you just need one story of people saying, ever heard of flip bits, cosmic events?  And maybe at some times this is warranted, but I think from what both of you just laid out, pretty exceedingly rare. And the fact that it is a known phenomenon that is sometimes real and can at least be researched, if not mitigated right away, is the first step. Yeah, and usually a flipped bit doesn't cause a catastrophic error. Certainly in a complex system like a car, it would be exceedingly rare for that to happen. Even in Moe, with the pacemaker that they use as an example of the BBC story, the pacemaker just reset to default when that happened. It wasn't like it stopped altogether, but she noticed, she's like, this isn't the way it usually feels and so got it looked at. So yeah, usually a flipped bit doesn't cause catastrophic errors and they're rare. But interesting to know that that's real because I've often thought about that. Larry and Elana was joking, it's like, oh, now when I make a coding error, I can just blame it on cosmic rays. It is a real thing. Well, folks, it's time to get our holiday gift card list in order. It is that time of year. Each year, we send every patron who wants one a holiday gift card with exclusive art from Len Peralta. We've seen what he's done this year and it's very nice. I think it will inspire joy in your home as well. If you'd like the card, make sure you're a patron, first of all, and then check patreon.com slash pledges to make sure that we have your proper mailing address if you want something sent to you. If not, no worries. But if you do do that by November 15th, please and get the exclusive DNS holiday card, DTNS holiday card mailed to you from us. DNS, that's something. Yeah, we need your actual mailing address, not your DNS. That's a good point. Cosmic rays need not apply. When browsing listings on Airbnb, potential guests can sometimes be hit with a little sticker shock. That's because the service shows the nightly rate for a booking, but does not show required fees that might go along with it. Things like security deposits, cleaning fees, even extra fees like for pets or peated pools, for example. So that cute little vacation rental might not be quite as much of a steal as it appeared to be at first blush. CEO Brian Chesky has announced that Airbnb is making changes to make pricing more transparent. Yeah, specifically starting in December, Airbnb will now let customers set a toggle switch to show the total cost of stays when they're just browsing around. That includes fees rather than just the nightly fee, which is how it's always worked in the past, though it still won't include taxes. When you check out, you're still going to be paying a little bit more, but many people are used to that buying things online in general. So the pricing will show across the app, including in search, in maps, and also wish lists, as long as the user stays logged in. If they log out, they would have to choose the selection again when they log back in. The service will also factor in the total cost of stays more heavily in search results, regardless of whether or not users toggle on total cost. Now, additionally, in the coming months, the platform is going to roll out more discount tools for hosts, letting them set seasonal or weekend discount pricing, and any host checkout requests will be shown to guests before they book. You probably as a person who rents places like all of these changes, right? You want to see the actual cost of what you're booking. You want to see the checkout requests. Like, am I going to have to, like, change the sheets and throw them in the dryer or something before? It's good to know that before you book, but Sarah, you actually manage an Airbnb and some of these are good and some of these are not from your end of what happens, right? 100%.  It is a place that a large family typically books for around a week to stay at. That adds up, especially in high season where our rates go up a little bit, which is a separate conversation.  It's going to be more fun. If you break that down, a hotel would be so much more expensive and we all wouldn't be kind of in this nice homey atmosphere. Makes a lot of sense.  And yes, sometimes an extra service fee, if they want to heat the pool in the winter, for example, that costs us money, so it costs them money. And that can all lead to people saying, well, hold on a second, like this is insane. Does it really cost this much? And the thing is, is like, yeah, it's going to cost that much either way. But you might as well know that ahead of time, so that I don't have to have that uncomfortable conversation with you afterwards. And I think that property managers slash owners of any vacation rental knows how this works, where you, you know, you have people kind of wanting to go through and itemize stuff later on where you think, that's the whole reason we were on this platform. So that we didn't have to have this conversation. It was all just sort of taken care of for us. And that's why Airbnb is taking a fee. You know, they take a cut of all of this from the booker and the person who's collecting the money who is offering a house. So I think these changes are really good. But I have already seen some property management pushback on the same. Well, now we have to lower our prices because the sticker shock is going to put more people off ahead of time. I don't really, you know, I'm not sure. I think maybe we all just sort of get used to it. Well, yeah, if everybody on the platform is showing their fees, then the only ones that would have sticker shock is if your cleaning fees are significantly greater, I think. Right. It is a song and dance, though. It really is. One of the other things that you mentioned, Tom, of the platform, rolling out more discount tools for hosts and being able to set seasonal or, you know, higher pricing, depending on, you know, for example, we don't have anybody booked here for Christmas. And Christmas is historically like, you know, it's a pretty big week. High demand. Yeah. High demand. And, you know, a lot of people just aren't traveling. Maybe they're saving some cash. Maybe they've already done another trip earlier in the year.  But that kind of thing would be pretty great because right now, if I want to set 2023 pricing, it is a manual process, right? Go through and methodically. Each day. Every day. You can say Airbnb just kind of like, give me what you think that pricing for stuff in my general area for the same kind of place is going for and just hands off. But they're not going to... They're not going to adjust it for the weekends or for the seasons, right? Yeah. Or if you know, like 4th of July is like a slam dunk for us. You're going to have to go and do that manually. Exactly. And so that would be nice. But I, you know, again, as a Airbnb user on both sides, I've stayed at lots of Airbnb's as a guest over the years with mixed results. But that's sort of the beauty of it. How much are these cleaning fees anyway, though? Like getting back to the fee thing. Like I know the weekend tools makes it easier on your end. But I mean, is it really raising the end price that much? Not really.  Probably around $300. You know, it's like, this is not some sort of a money-making graph. Yeah. As a percentage of what is being paid already. Yeah. But it does add to the like feeling that you've been nickled and dimed. And I get that. I definitely get that. Well, and if you're looking at a hotel rate, the hotel's going to hide any of its like resort fees and stuff too. So then it's not apples to apples anymore. I get that too. I mean, the nice thing about a hotel, though, is that you go, we've splurged, right?  But that is all kind of hidden in the costs. So it might hurt up front, but it hurts less later. And I think that's what Airbnb is going for. Oh, no, I'm saying like hotels do the fee thing too, where you're like, wait, it was only $400 a night, but it ended up being $500 a night because they had a resort fee and a parking fee.  Yeah, well, you know, it's a feed happy world. Yeah, it is. Well, well, fees aside, if you've ever listened to a deep philosophical conversation and disappointed that it was too coherent and also just didn't go on indefinitely, well, then you might like to check out a new website from the Italian artist and programmer Giacomo Macelli called The Infinite Conversation featuring an AI-powered chat between virtual avatars of the very real German director Werner Herzog and the Slovenian philosopher Slavog Zizek. Macelli used a popular language model tuned on interviews and content from both of the speakers and then used AI voice generation to imitate how they would be speaking the dialogue. A new segment is added in daily, so it kind of does go on forever. Macelli notes, new segments can be generated at a faster speed than what it takes to listen to them. In theory, this conversation could continue until the end of time. The site is meant to be commentary on the social impact of audio deep fakes. This is the best effort. Oh, I mean, just proof of concept, right? Like, okay. I've got my media conversation that will never end.  When does this break down? I don't want an infant conversation where that happens. I don't know what kind of moderation is happening with these AI folks, but it's something. We are too early. That was them. You are asking about the future. I think that maybe my version of materialism will be our centuries version of Kantian idealism. I think your fears are relaxed, Ayaz, because it's trained specifically on Herzog and Zizek. It probably is more repetitive than it is off the rails. Okay, that's good then. Rails are good for some of the stuff. It's not trained on the wide open internet, right? So there's some rails around it. I feel like Nazism or Stalinism, a palpable experience of how not only God dies, but also humanity itself dies. I feel like this would be soothing to me at night. I could kind of be like, I'm kind of tired, but I want to listen to something for a little bit. How about the infinite conversation? And it just keeps going. And it just keeps going, yeah. Alright, something else that keeps going, thanks to you, is email feedback at dailytechnewshow.com. What do we have in the mailbag? This one comes from Karleen. Karleen is talking in reference to our conversation last week about Amazon's changes to Prime Music. Amazon said, hey, we're adding a bunch of new stuff for you. Karleen says, to me, they've taken away a cool small feature and replaced it with an upsell I'll never use. Like Rich, I have kids that loved asking Amazon's assistant, we'll call her A, to play a song. When we experienced the change the other night, my three-year-old couldn't understand why A wouldn't play ba-ba black sheep over and over. My older kids had a two-go-sleep playlist that's now shuffled with similar songs. When you're particular about something as a kid, that does not work well. Karleen says, we loved having a specific song or playlist on demand played through A, but now it's just frustrating. I've been deep into the Echo ecosystem, but its lack of a straightforward way to connect with YouTube music and now this really makes me consider switching to Google Home. Well, if you're in the YouTube music system, I guess that makes sense. I have always had the Echo connected to Spotify and Apple music, so we've never really relied on Amazon music. But that said, I totally get it, Karleen, where your kids are like, no, but it always works this way. And you're like, well, I don't want to have to pay extra to make it work for my kids that way. That line about shuffled with similar songs would be maddening for adults, let alone children. I just think that's kind of a horrible little switch. I've also used Echoes for a long time. I don't use their music service. I use YouTube music. It works alright as long as your playlist or your playlist, but that allows you to at least upload your stuff. I've had substitutions happen where I had a track of a song that I liked that was on their service and then it got switched for a live version because they had the rights to that. That is horrible. It sounds similar to this method. And there is a solution which is pay $8.99 a month. That's what Amazon's saying. Like, you want these features that you came to rely on? Well, you have to pay for them now. What is this? Verified check mark? Geez. It's a dollar more than a verified check mark. I have the solution when the kids get upset that they can't play Bob-Bob Black Sheep, just put on infinite conversation. I could never direct a film liking Matt Burtman's The Suppense. What's not to like? Yeah, the kids will go right to sleep. That's right. Well, you know who doesn't put us to sleep is IA's actor because he always makes the show better. IA's, what have you been up to lately? I've been working on This Old Nerd. That's a show where we show you how to have the most tech-forward home in life as possible in as little time as you need because the thing is we've got a lot of responsibilities as adults or older people and you might want to take care of them. So, like, the projects are quick and they're simple. And I'm just thinking right now, like, how I would come up with a role in my own solution to not have to pay Amazon to do this, create my own playlists, make sure they're available on all the echos. I'm pretty sure there's a way to roll your own using, like, Plex. I got to think about that. And that's the kind of stuff we do. Fantastic. I also want to thank our brand new bosses, Anastasia and Aaron, who just started backing us on Patreon. Thank you, Anastasia. Thank you, Aaron, for finding the value in independent tech journalism. If you're out there listening and you're getting some value out of us and you can afford, we know not everybody can right now, but if you can afford to pick everybody else up and give a little value back, please do Patreon.com slash DTNS. Indeed. Speaking of patrons, stick around for the extended show Good Day Internet. We roll right into it when DTNS wraps up. But just a reminder, you can catch the show Monday through Friday at 4 p.m. Eastern. That's 2100 UTC. You can find out more at dailytechnewshow.com slash live. We'll be back talking about YouTube shorts tomorrow with Lamar Wilson. He has thoughts. Talk to you then.


This week I'm talking about the Comet Hitchhiker, one of the cool projects to emerge out of my favorite program at NASA, NIAC. NIAC stands for NASA Innovative Advanced Concepts and it's this amazing program that funds the more sci-fi futuristic out there, sometimes very weird projects that could actually transform future space missions. One of the concepts to emerge from the NIAC program that I think is incredibly cool is the Comet Hitchhiker. It's a project that when I first heard about it I wasn't quite sure what was cool about it because we already have a really badass space probe Rosetta that's exploring a comet so why do we need another comet exploring space probe? Well Comet Hitchhiker isn't necessarily a concept just to go and explore a comet. The Comet Hitchhiker is actually a concept to use a comet as a propulsion system to be able to explore the solar system twice as fast as any of our current space probes are. Essentially the idea for the Comet Hitchhiker probe is to actually send up a space probe and have it harpoon into a comet and then reel out a huge very incredibly long tether and be able to actually harvest the kinetic energy from that comet catch up to the velocity of that comet and then utilize that comet as essentially a hitchhiking system so that the probe could explore the solar system twice as fast. This means that a space probe utilizing a comet as a propulsion system could actually reach Pluto in about five and a half years, about half the time that it's taking new horizons to go explore Pluto which has been a little bit under 10 years. To me there's some sort of space geek romanticism about this, the idea of using comets or asteroids or other natural celestial bodies in our solar system as propulsion systems to allow us to explore space in a much faster and much cooler way. Providing funding for incredibly cool projects like the comet hitchhiker is one of the reasons why I love the NASA innovative advanced concepts program so much. Although admittedly I'm incredibly biased because I am on their external council along with really cool sci-fi authors, quantum physicists and other really amazing scientists that help advise the program and help propel it forward. But NIAC is cool for a lot of reasons and one of which is actually the fact that anyone can actually propose an idea to NIAC. Anyone can submit a white paper. Usually they open up the white paper call around October or so and anyone can submit an idea for how future space missions could be transformed in a futuristic sci-fi yet credible and realistic way and they actually go on to fund some of those proposals and actually fund the research and development behind it so that it can really turn science fiction into science fact. Thanks so much for clicking the play button and geeking out with me today. I hope you enjoyed learning about the comet hitchhiker. I think I'll also try and talk about other NIAC projects in future episodes because there's an endless amount of them and they are endlessly endlessly cool. Remember to subscribe on YouTube so you can get those videos a lot easier and also donate to the Patreon campaign to support videos like this one on the tomorrow channel.


Number eight on our list is the Minority Report. Released in 2002 and directed by Steven Spielberg, the movie predicted the use of biometrics and facial recognition technology in law enforcement. The story is set in a future where crime has been all but eliminated thanks to a new technology that can predict when and where a crime will happen. The film presents a world where law enforcement uses a combination of biometrics and facial recognition technology to track criminals and prevent crime. Today, biometrics and facial recognition technology have become increasingly common in law enforcement and other security-related fields. Governments, law enforcement agencies, and private companies use these technologies for surveillance, identification, and tracking purposes. The Minority Report's prediction of biometrics and facial recognition technology in law enforcement was quite accurate, although some of the specific technologies and practices shown in the movie are still in development.