and he's Redon. We usually hang out at the local haggar space in Albania, which is a country in the Western Balkans. We have helped co-organize open source conference, Albania, for the previous editions. In 2017, we did our first crypto party together with Arjen Kampouis, and we managed to, with the help of the municipality of Tirana, publish on OpenStreetMap a lot of geographical data regarding the city of Tirana. We also helped them migrate to NextCloud, which is an open source solution for managing your files, and it's a solution they are using to this day. So before going into our little project, it's very important to give some context about... So it's a lot of different people here, so it's a bit important to also know the local context where we come from. Apologies for the Albanian, but I will explain. These are news from some articles that are related to this talk as well. So in 2009, in Albania, we had the first known data leak that happened, and all the data from the civil registry, which means names, surnames, IDs, they were leaked, and you can find them also today, unfortunately. And this was the first known case. We don't know if there are other cases as well. And basically, after this, in 2013, this was between the changes of the government. We had elections that year, and what happened is that people went to the central tax office in the physical servers, and they were caught on video, and they stayed there for a night. They went out and lots of data were deleted, which was pretty big. Until this day, for both these cases, we don't know if there are prosecutions in people that are other than the IT specialists that were working there, unfortunately. And in 2016, another interesting case of, you know, not respecting the digital rights was an MS Catcher's hardware and software package were sent to Albania from the Italian government to support the Ministry of Internal Affairs on how to do proper surveillance in cases the police needs to investigate. But what happened is that the Ministry of Internal Affairs kept the hardware and everything with it for one year, and it was suspected that it was also used without any notification of anyone other than the Ministry of Internal Affairs at the time. And also, this was a big scandal, but for us, unfortunately, it was very sad because in the public discussion, this was not debated at all. It was just a political issue, and nobody was talking about digital rights and how bad this was at the time. So we were frustrated that this was not being discussed at the time. And of course, the same situation happened in Descalade in 2021 with more data leaks. Yeah, so ever since 2021, we've been getting a few more data leaks and these ones have been far more comprehensive. The first example happened in April of 2021 where the data of 910,000 voters was exposed to the public. And we're talking stuff like social security number, your living address, your phone number, the license plate of your vehicle, and also later, more data leaks came. So it's the one-third of the population, basically, because Albania has 3 million people, so approximately. And if you look at the collection of the data, it's pretty clear that these data have gotten out from governmental services. So in summer of 2021, it turns out that one of the parties in Albania was using this data as a way to study, let's say, the voters and see how they could turn this into their advantage. So for each person who had a name, surname, all the ID and some comments, for example, Redon, he is affiliated with our party, or he's not. If he's not affiliated with our party, we need to talk to him so that we change. So it was a proper database, but the data were from different governmental agencies in one. Yeah. Which was pretty... And this was the first time that the concern about digital rights was when big in Albania, which made us happy and sad at the same time for obvious reasons. Normally, the leak of such data, because you can't really change your social security number, for example, is that it really shocks you. And it takes some time for you to process what happened. However, what happened in Albania was in summer of 2021, these data came out, and then less than six months in December, our salaries became public. So all of the salaries of everybody who's working anywhere were now open for the entire public, and at least the data set was free. You could download it for free, so there's that. Okay, you seem shocked. Okay, there is more. We have 10 more minutes, so no worries. So in May 2022, which is some months before, our government decided pretty fast that every governmental services, 95% of governmental services will go through a governmental portal. So whatever you need as a paperwork, you have to go through there, which might be a good idea or bad, but if you do it fast, bad things usually happen as we all know. So for more context, a lot of the population in Albania is not very tech literate, and most of them don't have the tools to access this interface. So another phenomenon that usually happens is people go to internet cafes and ask people there to sign up their account, which when we're talking about the account to interact with your government, that might not be the greatest idea out there. And also it's not only this that people don't know how to use it. It's also that my parents, for example, they're old. My mom has a burner phone. Last time it was charged, it was 2008 probably, and it's not a smartphone, so it's very hard. So everyone is trying to help their families to get into this. And because this went on very fast, it was launched very fast, before us coming here one week or 10 days before, it was hacked. So until now, what hacked means nobody knows because there is not a proper report right now of how many data, what happened, and et cetera, et cetera. What we do know is that our state was offline for two weeks. For two weeks. And when we were at the plane coming here, like switching airports, the people that did this, they started leaking also whatever they have found gradually. So anyway, this is sorry about this, but it's important to have a lot of context. And one last case, I will not talk about any breaches. We will not talk about breaches anymore. So in 2009, it was introduced a law that said, it was a very vague law that said that the police has the right to do surveillance without any request to a prosecution, to a prosecutor. Which in, I'm not a legal person, but we know that it's anti-constitutional in the first case, so there need to be checks and balances, right? Yeah, there tends to be a little pattern going on with how our digital rights are being respected. And he's into memes because he's younger than me. Yeah, I'm an internet kid, so. So the public rhetoric always was, we don't know about this tech thing. Also journalists that we talked all the time, they said we don't know, like it's very complicated to us, we don't understand. And also the general argument from the governments, not only one, but in general is that these things happen to every government. Even the ones that we think that are more, have more bigger budgets, they happen all the time. This was the first argument, and it still is today. And the second was, you've heard this before, well, you have nothing to fear if you have nothing to hide. And I'm not mentioning who started saying this first. See, this saying is quite controversial, but I think it's kind of right because if the government has nothing to fear, they also should have nothing to hide. Well, what this means, as I mentioned before, the general rhetoric is, this is okay, it's normal, it happens. And we say, yes, okay, but we need to raise awareness about this. And also as Boris mentioned, these things should apply transparency and having nothing to hide should apply to the governments too.  And the reason they mentioned the hijacking there is because we want to change the rhetoric of the whole situation. So the collective is talking about other issues that are concerning Albanian society, and our focus here is what's happened with surveillance and the digital rights in Albania as well. So that's why we launched Nothing to Hide, dot-the-bapticcenter.net, which is a map of mapping points of surveillance in Albania, starting from Tirana. This is the map. Yeah, so this is Tirana right here, and if you see this little area right there, it has 62 cameras surveilling public area. So if you open one of them up, you can see more info on that. One important point, we are not mapping all the cameras, we are only mapping cameras that are pointing in the public space. And these are business cameras because they need by law to have, which is also vague law, which says that you need to monitor your business if you are in the city center or anywhere else, but they don't specify that you need only to map your business, your property. So these are only cameras that are in the public area, and also these are done in a few amount of time, which means we're gonna do this until September, right? The most outrageous thing I've seen so far, I was in the seaside, and this is, what's the name? It's a mole, like it goes in the sea and it has this wooden thing that you walk. Structure, and a hotel that is really far away from this had put monitoring cameras there, and when asked around why this is happening, the answer was like, I don't know, because nobody told us that we cannot do this, right? So you go to the beach, the beach is public space by this definition. So if you go to the open street map, it's right there. And if you cannot see from the distance, it's not just a camera, it's two and actually more that are hitting. More cameras that go along the way. So that's a fun spot. And so it's a combination of governmental practices going bad, but also not having awareness of what you need to respect in terms of, other people's privacy and digital space. So I'll go really quickly into the tech behind it. We are running Ushahidi, which is a platform for crowdsourcing data, so it was perfect for this fit. We are hosting in a very stable data center called My Bedroom. It's usually open nine to five. For the base map, we use open street map and we just render the additional points on top. For the license, we wanna have this under public domain because it's crowdsourced data, but this might be tricky, so there is still discussion going on. One important thing about this is that we, after we launched this, two things happened. People started, like we did some workshops in the city telling people how to do it. It's very easy. We're gonna have some screenshots. You just take a photo, geolocation and... So here is the form where you're filling the data. It says geodata, a photo and a short description. And the idea is that we are trying to make it easy for people to do this, but going back to the public domain thing, people were saying, oh, this is super nice. It's like Pokemon Go, which also is funny, but also very concerning at the same time because it's being gamified. But we also got some researchers saying that, hey, can you give us this data because we need to do some more research and also some people that know the context of the law so that we can have even more outcomes out of this. So, yeah, this is the project. And... Faluminderid, as we say here. Faluminderid. No, it's on time. Well, thank you so much. I've never heard of this, and it's not amazing. Obviously it's awful, but it's such an interesting subject and I think it's amazing what you've done. If there are any questions, there are mics in the middle. Oh, we're gonna get questions? If you're comfortable with that. We didn't do it. That's the answer for all the questions. We are not the ones to do it. No, I'm joking. No, they didn't do anything. Like what? Yeah, we're innocent. No, obviously not. They didn't do anything, just so you know. Well, thank you then. Okay, thanks. And another applause. No, if there are questions, I was joking before. Oh, okay. So I just heard from an anonymous source that if there are questions, you can ask them. Thank you. So when did you launch the app? Was that this year? Yeah, that happened this year. Two months ago. Yeah, how popular did it get? So as of right now, we have around 100 data points. 96 of them are just in Tirana. Sorry, it's up to 106 right now. Last night it was 100 though. So yeah. But I think from what we've observed, these are only a few of them. And until September, we expect to have more people and what we're doing right now is doing some workshops so that people understand how they can contribute there. But we're expecting, based on what we see around, there are many, many more cameras that we can see. And not only in Tirana, in other cities in Albania as well. See, the thing when you start mapping here is you know there's a lot of public cameras around, but you never really think about how much there are and how much on the street you're on right now. So this project really helps. It helped me as well with putting that into perspective. Thank you. Great question. If there are any other questions? Oh, one more. Thank you for this talk. If you could lower the mic. Have you thought about maybe rolling this out in other cities in other countries? I'm sure there will be quite some animus and enthusiasm for it. I know in my city I would like to replicate this. So I know after we started this, we understood that there are also some other cities doing this. So New York has, people in New York have done this. And in London, which I think we know that it's very, has lots of cameras. But if we are, once we do all the gathering of the data in Tirana, we'll start documenting the process of how we can replicate this. Because it's, but also it's very important to document the, to have in on board, if you want to replicate this, to have on board also people that know about the local, law context of what's happening. So again, we are, in Albania, we are just monitoring cameras that are monitoring public areas. That might not be lawful in whatever country or city you are living. So we will document this so that everybody can replicate it after. Great, thanks. Hi, so two questions. First, have you thought about, I guess maybe, I don't know, depends on the trust that you have in government for people to register, they have to register these cameras themselves so you can get like a public register that you can ask for. And the second thing is, there's companies like Ring that make private people do this. Yeah, right. Are you also tracking those, well Ring holes? Can I get the first question for sure? So for the first question, okay, go the second one because I want to... Okay, so in regards to the Ring cameras, what we really want to map is just cameras that face public areas. So for example, views of the street. Ring cameras, for example, are not popular in Albania at all. We have the manual version where you have to stand behind the door to see who's on the other side. So we haven't come across that issue but it's quite an interesting one. But again, it's about what the law says. So if you can do it in your city or country, we shouldn't monitor it because it's part of the law, let's say, if you trust your government. But in our case, it's not. It's very vague. We don't understand what you can monitor or not and we're trying to raise awareness with it. So even if it's a Ring camera in your city and it's your private property, as long as you're monitoring me passing as a pedestrian outside your door, that shouldn't be the case because that's not loud. There's also when you're, for instance, when you have a job where you have to go to, like the newspaper boy, you're 16 years old and you have to go to somebody's door and you get filmed. Right. In whatever state you are at six o'clock in the morning. I could personally object to that. I wouldn't bring papers to such a person if I were a paper boy. Yeah, here in the Netherlands it's actually illegal to film people in public spaces, I believe, without their permission. So cameras that are on public street, you can, if you have a personal camera, you can only do it on your personal property. So let's say I have a house I wanna protect with a camera. I can't put it at the front of my garden and film the entire street. I can only film my garden and my front door.  You get filmed, you get sent to, don't know which data center, and you cannot approve or disapprove. And the same goes for people that are in their official capacity.  And if the door is facing the street, then all bets are off. And that's why these things are very important because we feel, again, we have the local context of Albania. We think that digital literacy is at a very low point, very low at a worldwide level. So people don't, what we're discussing right now, they don't understand that this is important or whatever. And that's why we all need to do more about explaining why this is okay or it's not okay. Like putting things into perspective. Just like, for example, this shows how surveilled you are at the moment. Regarding your first question, quick answer, it seems like we don't trust the government where we live. The thing is that we just wanted to work properly. That's nothing against them. But they are now introducing a law that will put all the cameras from businesses to in one directory. So basically store everything. So the government will have access, immediate access to all the cameras. First of all, it's impossible technically because you need all the cameras have different software and setup, et cetera, et cetera. And the second, only the thought of it, it's like cringy, right? But, and that's very, the police should go after the bad people, the bad guys. But right now we'd have no, after all the cases that we've shown, we have no indication that the data are handled properly. And we've had more time, we can go on and have more cases where the data in Albania are not handled properly by government officials. So it's not about, as I mentioned before, we don't have anything about trusting, but we have all the indications in the world that they either don't know what they're doing or they're doing this on purpose or even worse the combination of both. And there's another factor on top of that which is we don't have an indication that the government knows where these cameras are either. So really the only option to go forward would be to crowdsource that data. So we allow people to submit either anonymously or with their profile, because we wanna respect their right. But it seems like there is no other way to have such information. Okay, thank you. Thank you, thanks. Then another big applause. Thank you so much. Thank you. Then the next speaker, I don't know if he's here, his name is Matthew, ah, there you are. Well, I came in a little late because I thought it was a two, it was a one, so it was like running. That's why I have a fork in my pocket. I was eating. So I asked what is it about and I didn't really understand, but that actually made me super excited for the talk because now I have no idea yet what it's about and the more I can learn. So I believe it's about software. Is that correct, Matthew? Yes, I know something. But he's going to tell so much more about it.  Are you ready? Or should I keep talking? Yeah, keep talking. I just heard that they're still setting something up. So in the meantime, we're going to play a little game I heard of yesterday. So I need you for that. So everyone's attention, yeah, great, thank you. So this is how the game goes. I start with the number one and then someone yells two, then someone else yells three. But you can't say a number at the same time. So if I say one, someone else can say one as well. Any questions? Okay, so one. Oh, again. No, we need to start at one. One, six. Okay, one last time and we were ready to go then? Almost, okay. One. Zero. Okay, he's ready. Well, thank you and a big applause for Matthew. So who here has heard of Docker? Wow, that's amazing. I thought I was gonna have to explain what Docker is, but you all know what it is, right? Great. So this talk is called useflake.nix, not Dockerfile. This is, I don't know if I'm preaching to the choir. Maybe you know what the issues are with building software with Docker. Maybe you don't. But I'm gonna try and explain why it's not really that reproducible and why you can use Nix instead. So why use Dockerfiles? Well, I don't know, but why use flake.nix? Because build via Dockerfiles aren't reproducible, but they are repeatable. So that means that you can run the same instructions, but it does not mean that you'll get the same result. So what is Nix? Nix is an expression language. It's a domain-specific language, which was invented by ElcoDulstra and his PhD thesis in 2003. And it's lazily evaluated, which means it's more performant for doing package management. It's a purely functional programming language, which means it's not procedural. So the order in which you define things does not matter. It's declarative rather than imperative, so things are defined as an expression rather than as a sequence of events that you want to occur, much like in a Dockerfile. And yeah, in that way, everything is an expression and there are no side effects. So here's a basic abstract example. This is called an attribute set. In this example, X is equal to a list, which has a string inside of it, Y. Y is equal to one, and Z is equal to the expression one plus one. So let's evaluate what X would have been. So X is a string Y inside of a list. And the same for Y, it's just one. And Z is one plus one, which is two. So here's a basic concrete example of me compiling Hello World from GNU, source code. So I'm gonna cat the examples, Hello World.Nix, this is the Nix expression, which defines how to compile the software. And then I'm gonna Nix build it, I'm gonna look at the result that it creates. The result is a sim link to this object store called slash Nix slash store, where the immutable software packages live. All right. We can see that it's dynamically linked X86 executable with its interpreter patched to the correct interpreter and then I run it at the end. So you see Hello World is there. So what is the expression at the top where it says let packages import Nix packages, et cetera. So that is a function call to standard m.mkderivation. The first argument is name, which is a string. So I'm gonna call this package Hello World. And the source code is gonna come from GNU's FTP server. And we're gonna hash this, and this is really important. We're gonna say what the char256 sum is ahead of time. Now this way, if anyone else sees the expression in the future and they build it and that tarball has changed, well we'll know about it because the char256 won't match. So this data is really important for reproducibility and security. So by comparison, let's see what a Docker file would look like. So from Ubuntu latest, there's two problems here, right? Ubuntu, even if we could find the original Docker files for Ubuntu, could we reproduce it or do they have many steps inside of it that aren't reproducible? Like apt install this, apt install that. Because every time you do apt install, you've lost the reproducibility because it's gonna give you a different result the next time it runs. Latest, latest when? When I run the Docker build. So the Docker files are not intrinsically attached to the results. So the result of a Docker file is basically like a binary, you give that binary to people and you may never see the Docker file ever again. And that's not quite true for Nix expressions. So apt get update, it's gonna resolve a different package list the next time it runs. So the next time I run Docker build, hello might just not be there. So we've got to run it five times and then hopefully Debian servers are up again rather than down. And yeah, but that's not the only problem. Every time we do apt get install, hello, it's gonna create a package database and this package database is gonna have timestamps in it. There's gonna be tons of reproducibility issues just at every level in this Docker file. And then last offender is cmd hello. This assumes that the hello package actually puts a binary called hello on the path. So maybe hello is not the name, maybe it's hello-world. So there's nothing but assumptions in this Docker file. And indeed, if we use this method here where we save the results of building it into a table and then we look at the table, the table is different. Now this isn't the full story, this is a bit of a cheat, right? As a matter of fact, if you extract this, you'll get another table and inside of that is a layer and a file system hierarchy like slash user slash bin, et cetera. So we'd have to inspect that with Difascope to understand the true reason that this is not reproducible. But I mean, this is a nice example because it shows that even when they package the table for the OCI image, this table, this image that we're gonna load into Docker, even that step is not necessarily reproducible because tables pack and unpack, serialize and deserialize in a different order every time operations are performed. So how do we do this with a Nixflake instead? So there's a function someone made called, I only wrote this presentation this morning, so I missed that out, but it's called Docker Tools Build Layered Image, right? So someone in Nix packages, which is a library of 80,000 software packages and Nix expressions and functions and things, they made this function called Build Layered Image and this is essentially a reproducible bash script for producing container images, right? So my container image equals running that function with the first argument name, my container image, the tag, latest. Content is a list of things that I want to be in the container and config.cmd is the entry point that we saw in the Docker file earlier, which was hello. So let's just have a look here. So this hello here, that's what we're gonna map to in the Nix expression, config.cmd equals hello. So this is the first thing that's gonna run on the container boots. So this is in a data structure called a flake. So a flake has inputs and outputs. We say inputs.nixpackages.url equals this GitHub repo and whenever we run a Nix command on this, it's actually gonna generate a flake.lock. So I'd just like to show you that before I get too far in. So flake.lock. So we no longer have that problem of like latest being latest when I run the command because it creates a lock file and tells you what it was when I run the command and this is immutable and stored in the Git repo where I provide these expressions or tell you to run it from. So yeah, let's build it. So we're gonna build my container image. We're gonna look in the result, then we're gonna load that result into Docker and then we're gonna run it with Docker and this has all been done, like the container image has been built with Nix reproducibly and then ran with Docker. So I'm just gonna run that. Oh dear. All right, there we go. I got scared there for a moment. Okay, so it created a result, put it in the Nix store where it lives reproducibly and it loaded it into Docker and then it ran it. So there you go. Much more reproducible than the Docker file, right? So why is this the case? So Docker is repeatable but not reproducible to find instructions, but it trusts the internet unconditionally and it doesn't perform any hashing or at least it doesn't encourage people to do that. Docker files do not provide you with a tool set for performing reproducible builds and Nix is basically a C++ binary written by Elko Dulsher which implements the Nix expression language which gives you a tool set for implementing reproducible builds. So what does Nix guarantee? So it guarantees that we're gonna get the same input from the internet every time and we're gonna perform the build process inside of a sandbox and hopefully the result is deterministic. It guarantees that, but it does not guarantee that the build process in fact is deterministic. An example of this would be the Java compiler. The Java compiler will put timestamps into every jar file it creates every piece of Java source code. Now of course we're not gonna get rid of the system call that allows the process to gather the time at this point in time. But that was a decision because it broke a lot of build processes. So instead we have to do things like touch 1970 at every build step so that we get rid of the timestamp and the intermediate steps when we compile things. So yeah, there's lots of reasons that a build may not be deterministic and Nix can't help with that. But what it can do is perform the same build with the same inputs every single time and hope that the output's deterministic which is a lot more than many other tools can do. So, do I have any extra time? Do I have? Yes, we have enough time for questions. Oh yeah, I didn't wanna go to question straight away. I just wanted to show three really cool things. So Nix shell is a way of trying things before you buy. So I'm gonna SSH into my server because the internet here might just drop out. So I'm gonna Nix build, oh sorry, Nix shell. Nix packages, hashtag, I don't know, Python three. And the reason I'm gonna do that is because I have Python three now. But if I get out of the Python three interpreter and try and run Python three again after exiting out of this temporary shell, I don't have Python three. I don't have Python on any of my systems installed globally, right? It's just, I install it when I need it and only when it's necessary. Now, because it's an expression language, if I go through the REPL, I can say something like let's load Nix packages and then Python three has a member function inside of it with packages. And I can say inside of P, put all of the whatever it is, 20,000 Python libraries that exist in the world from PyPy. And I'm gonna give it a list of Python libraries that I want for this particular instance of Python. P dot, I don't know, NumPy. It's gonna evaluate that and create a derivation and then I'm gonna build that derivation. And it's gonna do all of this reproducibly. So if you evaluated this expression, you get the same path, you get the same output path on your machine. And then I can LS in there and see that we've got bin and we've got Python interpreter. And if we run that, we'll have a Python three that can import NumPy. Oh, but if I exit this and exit again, you know, I don't have Python anymore. Going to a next rep on say I want Python three. Oh, gotta load next packages. Gonna build Python three. Notes that I'm not defining a function. I just want Python three. I don't want Python three with NumPy. Let's take a look in the output. This Python cannot import NumPy because there is no such thing. It's not global. There is no global state. There's no global thing that's being modified. Everything is a copy every single time with something added or without something added. Another thing that you can do is you can cross compile using Nix. So in Nix packages, there is a package set called packages cross, which is all of the 80,000 Nix packages that you can get. Whoops. Yeah, so like, I don't know, Python's there. We've got NumPy and we've got Firefox and we've got, you know, a set of 80,000 packages which we can do what we want with. So what do we want to cross compile all those 80,000 packages? Well, packages cross has any if we tap complete all of the architectures we want. So let's say risk five, 64 bit and then, I don't know, hello world. Now I think I've done this and this is another benefit of reproducible builds is that things are cached. I did this last month. It puts something in my slash Nix slash store. It's still, it's not going away.  The file system is memory is what they call it in the thesis. So I did this last month, so it's still there. So that's why it completed. But if I want to rebuild it just to show up, it can do this. And this is reproducibly cross compiling hello world for risk five, 64 bit. And it's done. And in slash bin, we have a dynamically linked risk five binary. And the fun part is despite the fact that I'm actually running on an X86 kernel, I can still, I can still actually execute this because I have something called bin FMT registrations enabled on my system. And the way that that's done is also very easy. Thanks to Nix. Because Nix OS of course has many options. I can just say, okay, bin FMT registrations. Yeah, I want to be able to run Windows binaries or ARM binaries. I can do that on my X86 system just by putting a list of emulated systems in this option. So that should convince you to use Nix OS if nothing else does. Yeah, I think I just showed off those three points. So any questions if I have time, if not, then that's my talk. Yeah, if there are any questions, the mics are still in the middle. If you walk the mic, otherwise the video doesn't have audio. So we all can hear you, but the people rewatching can't. In Dockerfile, you have a little bit closer to the mic, please. Yeah, thank you. In Dockerfiles, you have latest and that's great. You don't have to upgrade it. In half a year. Is there something like Nix, maybe specifiable latest up to this timestamp? Yeah, so I mean, Docker could if it wanted to, probably like implement a lock file. Although I haven't seen that. So the benefit of Nix here, right, is that you can't do such a thing as latest. It doesn't exist. And that's a good thing for reproducibility. So we take a look at this Dockerfile, right? It says latest. Now there's no, when you run the command, it's going to go and fetch the latest. And everyone that runs the Docker build command, every single person on the planet will get a very different result, right? There is no guarantee. So I have to target, I have to say like 2004, right? But that 2004 could still change technically. If I want it to be really reproducible and Docker does do this, you can specify a hash, right? And so, you know, there is a way around that, but it's the least of Docker's issues, right? So this is just one. No, well, the question would be, is there a Nix upgrade? Yes, indeed. So let's say flake.loc, flake.nix here has Nixos 20205. This is a tag, right? So it changes. So if I want to see what that is, I go into the flake.loc and we see that indeed it's the E3583 revision of Nix packages. Whoops. And if I go to Nix packages on GitHub and I go to that, that hash. What I'm saying, it's a lot of steps to keep your system up to date. No, it's not. I'm just showing you the full path as to how it's reproducible. So if we go to that commit, we'll see that that commit exists and this commit was made a few days ago, four days ago. So in four days, a lot might have happened. So we want to go on and we want to advance from this hash, this revision here. So all we have to do is Nix Lake update and it will go and find what the latest hash is. Looks like D1CA4EA, right? And so this is the steps that you do to update the lock file. And once that's done, right now it's extracted. It actually went and fetched the latest Nix packages and it's extracting the tarball on my laptop. So it's a bit slow because my laptop disk is a bit slow but that lock file will be updated. That was great. Okay, I think we need to be rounding up the questions. Do we have time for one more? Or should be, we've got one more speaker. So if you, the other questions, I think they can approach you afterwards because we really got to move it along. Sorry. Yep. Thank you so much. You know the question with the one sentence. If you go to repology.org, you will find of all the distros on the planet, all their versions and you will find that Nix packages has the most recent of any distro, beats the pants of anything. Top right, Nix packages unstable. It's the most fresh. It's the largest size. So it's got more packages than Arch. They're fresher than Arch. They're more up to date than Arch. They're more maintained than a lot of other distributions too. Thank you. Thank you so much. So for the next speaker, I learned what a subject was and I was like, I know nothing about that because his speech or talk is on the good old times. I wasn't born during those. I'm 15. I'm way too young for that. So I'm really, I'm really looking forward to hear what your generation know. I will be nice. What he has to say about the good old times. Thank you. Yay. Thank you. Yeah, this is going to be completely ad-lib. I didn't know I was going to do a talk until, I don't know, 20 minutes ago. So I'll just make it up completely. Oh, there's no time as well. So you'll just have to flag me because I want to keep track of the time. I don't know if it's that, but I will start from the point when I went over to the retro tent and I was with some people and they asked me about the machines there and somewhere I was familiar with, in particular, the Amiga, the Commodore Amiga computer. And it took me back to when, well, I suppose I lived through the 80s, but not the 70s. I missed the 70s. My first computer was a green monitor computer, eight-bit Commodore PET and then my family got an Amstrad CPC that had color and I could load games. I think my friends had games from cassette and after which then, my third computer was the Amiga 500 and I absolutely loved it. And it could do things that you just could not do on other systems at the time. So even basic concepts like what, how would it connect to the internet? And where would the internet run if I booted it up and tried to use the internet? What did the internet look like back then? Well, I don't know, I wasn't on it, but I'd read articles in magazines and the way we got software for the computer was just simply we could buy magazines or we could wait until we saved enough to go and buy some software from the, I don't know, Smith's or wherever the sales were at the time or even mail order. And one popular thing we used to do was order software from magazines where they would list like one pound per disc or alternatives as well. So yeah, before we had the internet, before a lot of my friends got maybe a computer with Windows in the mid-90s, people still had modems and they could dial up into, they could dial other machines that also had a modem on the phone line. So you couldn't tell the computer where to go and the computer would it be able to automatically route its way to its destination? You had to manually dial the number and download packages or files and you had the limitations of the size of the floppy disk so you had to split, if maybe your disk format wasn't big enough to contain the file, you had to split it up into pieces. Just out of interest, how many of you had an 8-bit micro back in the day? No, no one had an 8-bit micro back in the day. 16-bit micro, early games console, no. So yeah, what was that? MSX basic. MSX basic, excellent, nice. Someone else shouted? Yeah, I'd say earliest, yeah, the earliest, yeah. So yeah, it was interesting times and I think a lot of things were taken for granted, like how long things took, but when I look back now and I see the machines in the retro tent, a lot of them have been upgraded, they have SD cards, so you can load almost any package from that ever existed is on that one SD card because it's been scaled up so vastly and the packages are now tiny in comparison. And it really put things into perspective and occasionally I look back and I'll run an emulator and I'll forget how difficult things were and tricky and I'll forget, I might forget, oh, it really did take that long, oh, it didn't seem, I mean it wasn't such a big deal to put in a cassette, load a new game in from cassette or floppy disk, but yeah, we wrote it really cushy these days, we've got a really easy, we don't realize how convenient it is to have the facilities we've got on disk. I didn't have a hard disk drive, so a lot of things ran off ROM or from floppy disk. But yeah, it was a good memory trip. It must be still up, I don't know if there's dismantling it, but yeah, it'll be still up. Retro tent, so yeah, have a good look at all the machines in that retro tent and ask around, there's gonna be some guys that had old systems that love to talk about those things and just enjoy them as much as I did. Got me interested, I was interested from just a hobbyist perspective because I liked calculators and they were very simple devices. Bit more than a glorified calculator, bit less than a 3D graphics rendering engine, so PlayStations came out in 95-ish, something like that, is that right? No, it was earlier than that, I think it was 92, 93. Yeah, it all just went to PC, so yeah, definitely check out the retro tent. Yeah, good times for me and yeah, have fun. Hi. Thank you. Ah, it works. Well, thank you, I learned a lot because I wasn't there. And it's really, really, it's surprising that my dad talks about it sometimes. It's still, oh, there goes my fork, it still surprises me how far we've come in such a short time, like 20 years ago and now, yesterday I walked through an entire different world while shooting robots and 20 years ago my dad was like loading a file and it would take an hour. So it's amazing and you talk about it really lovely. Now, there's a question, so fired on. Hiya, that was cool. Thank you. Do you still have, like, cassettes or floppies? Yeah, we had a number six basics and it loaded things of cassettes and I remember having to reload games because the cassette would be a bit stuck. Have you had any issues with that too? Do you remember anything? That's right, that did happen some of the reasons, well, one of the common reasons for that, there's a few, could be that the tape head, I've experienced it, the tape head can become clogged over time, you get these cassettes that like clean ahead cassette tapes, but I would just simply get some, get a little drop of isopropyl alcohol on a Q-tip and just rub the head and that cleans it up nicely, it dries out quickly. So if you just want a quick fix to that, that's one try. Another try is, well, a slightly trickier one is the head alignment, there is a screw and you can get calibration tapes where you can align the head and you need to, maybe, I don't know, do you need an oscilloscope? I don't, yeah. You'd need to have a way of balancing that head so that there's a few ways and then you might even be able to load the tapes in and archive some, if they don't exist on the internet, you might be able to contribute to the archive. You might have some rare tapes, yeah. Okay, the last question for now and then I assume they can ask any other things that's fine. Yeah, it's not a question, I just wanted to mention my story about this. So, yeah, it's a question, actually. So, did you also exchange cassettes with your, like Game Boy cassettes or even console cassettes because I was living in a block apartment and we were, because we couldn't afford each one of us, like we were 10 friends, we couldn't afford each one of us to buy all the cassettes we wanted. So, one month, one of us, buy one and we exchanged it and it was also a game, like you were very good if you finished the game first and you could go in your face, everyone. Yeah, yeah. So, this is one of the first questions and the second I wanted to say is that I have a story with my dad. He came, I remember this very clearly, he came in my, I was playing a game and actually what happened is that he said, did you do your homework? I said, yes. He said, did you clean up your room? He said, yes. So, your mom wanted to help, did you? I said, yes, I did it. Okay, now go out because I want to play, I'm your father. So, he ran out of excuses, I just wanted to share because... Yeah, yeah, all these good old, yeah, thanks for that, yeah. Well, we did share some disks that were, a lot of the time, you get free games off the magazines, maybe we couldn't even buy the game so we'd all get the cover disks and the cover disks for that. Sometimes they'd have a full game, sometimes they had PD games, sometimes they'd have different types of games and some friends, if they were lucky enough to have modems, I didn't actually have a cassette player but my friends did, I was spoiled, I had a disk drive. So, but even the disk drives as well, people would, if they were lucky as well to have a modem which I didn't have, they could get onto the bulletin boards and get software from them and yeah. Well, you mentioned that it's, everything, you mentioned that it's everything goes slow but I think doing these exchanges was a very nice way of socializing and getting your friends and it was like a social network. Yeah, oh, they would leave the name in the intro. Yes. And it would, a scroller, a tech scroller and it'll put the number, yeah, that's good. That's amazing, I loved hearing the stories and it's so funny because I remember when I was a little smaller that we had a Wii and obviously that's way more advanced but we had to like, this thing got stuck and then you had to take it out and blow on the CD to clear off all the dust and then only then it will work. Which was one of my earliest tech memories that we were like, it just, to make it work but it's really nice to hear. Back in the day when Nintendo and I asked you to do the same with the cartridge, it was famous and people just go like a harmonica. Yeah, well, another big applause for. Thank you. And then that is Mark's the end of the lightning talks. I want to thank all of you and this is my last shift as a Herald so I really enjoyed having you as a public. Yeah, thank you, thank you. And I hope to see you all in three years at the next event. Bye bye. Yay. That also, I don't know if I'm going, but yeah. And also a big, big thanks to the organizer of all the lightning talks.


So, yeah, thank you for the introduction and I would like to thank the organizers. I feel extremely honored to be here. So I'll be talking about many body formulation of topological phases of matter. In particular, I'll be talking about symmetry-protected topological phases, such as topological insulators and the other variants. In particular, I will be focusing on the thermionic ones, which has extra complications. So we had to work a little bit harder. So I'd like to thank my collaborators, my student Hassan, who is graduating next spring and my former postdoc Ken. So I've been working on this subject for a few years by now and we have a series of publications. So you may have heard some version of my talk, or at least closely related to the topic which I'm going to talk about today. But today's focus will be time reversal symmetry, which, so, yeah, like I said, I've been working on this project of constructing many body topological invariants. But time reversal symmetry was almost the last symmetry I wanted to crack, which was the most difficult, but I thought it is most interesting, I think. So here's a quick overview. So as the title suggests it, I would be interested in many body formulations of topological phases. And I want to contrast this formulation with the single particle formulations of topological phases of matter. For example, for two-dimensional time reversal symmetric topological phases, yeah, not just for two-dimensional time reversal symmetric topological instilators, but many topological instilators of various kinds, we often rely on the band picture. So we have the bands and we have a gap and at each band we have a block web functions and the topological phases or topological invariants can be described in terms of the topology of this block web functions, which is parameterized by the single particle momentum. And for example, for 2D topological instilator, we have a formula for the topological instilator, which may be looking like this. So detail the form of the formula is not important now, but it suffices to say that it is written in the language of single particle web function. So I want to say this had the tremendous success in the sense that it predicted topological instilators and it got detected later and so on and so forth. Nevertheless, question remains, so if we have an electron-electro interactions, which may be weak, but which may be rather strong, and in that case, we want to talk about topological phases of matter, so we want to go beyond this formulation. So that is the main goal of this talk. So our formula for topological invariant, for example, for the case of topological instilator, looks like this and it looks rather complicated at this moment, unfortunately, but I just want to mention that in this formula, it's written entirely in terms of this many-body ground state and the reduced density matrix constructed out of the ground state. So there's no trace of single particle formulation in this formula. Everything is written in the many-body language. So the purpose of my talk is to explain what is in this formula and where it comes from. So this is one example, but there's other cases we can talk about and I'll discuss that. So let me say a few words about symmetry-protected topological phases and by that, the obvious example is topological instilator, but by that, I mean phase which is pretty gap and the more importantly, ground state is unique. So if you draw this tree diagram of phases of matter, we are interested in basically phases which cannot be detected by other parameters. So we need some sort of topological invariant to characterize them and we are interested in gap and we are also interested in particular kind of gap phases which is symmetry-protected topological phases. So just one more slide for SPT phase. So in SPT phase, we make topological distinction of quantum ground state in the presence of symmetry. So if we don't have symmetry, SPT phases may be adiabatically connected to topological trivial phases such as the atomic instilators, but if you impose some symmetry such as time reversal symmetry or some other symmetries, then your phase diagram will be disconnected into pieces like this. So then phase of your interest may not be connected to a trivial phase anymore in the presence of symmetry. So here we are making a distinction between different ground states in the presence of symmetry. So we are assuming symmetry is preserved. So there's no other parameter to distinguish different ground states and instead we need something topological invariant to distinguish different phases of different ground states. So I will explain the many body invariants first for the simplest example, which will be the Harden-Spain chain. So this is the Bosonic system. Whereas for fermionic systems such as topological instilators, I need a little bit more techniques or technology. So I will first describe basic strategy for the Bosonic cases, then I will move on to fermionic cases. So the key ingredient is something we call a partial transpose operation. I first defined this partial transpose operation for Bosonic systems and as it turns out inventing this operation for fermionic system is the kind of main obstacle or main difficult part, but for Bosonic part it's rather easy. So I consider Hilbert space, which has some tensor decomposition. So there are two parts in your Hilbert space.  So in this partial transpose, you take a transpose, but not for the whole density matrix, but you take the transport only for let's say the second Hilbert space. So it's maybe a little bit difficult to see here, but if you look at this equation carefully, I exchange column and low only for the second Hilbert space without touching the first Hilbert space. So J and L, they are swapped, but I and K are intact. So that's the partial transpose. So this is going to be my main tool to construct a topological invariant, but I'm not the first one who uses this operation. So this operation has been used in quantum information community to describe a quantum entanglement. So partial transpose has been used to construct some sort of entanglement measure, which I will not describe in detail, but there's some use in this history. But as it turns out, the partial transpose is also useful to construct a many-body topological invariant of symmetry-protected topological phases in the presence of time reversal symmetry. So the connection to time reversal symmetry maybe understood from the fact that taking transpose is basically like taking a complex conjugation, which is basically taking time reversal. So I want to go through some examples, which is the ordain chain. So it's the canonical example of symmetry-protected phases. It can be protected by various types of symmetries. For example, spin rotation protects the hardened phases being deformed into topological attribute state, but here I will be focusing on time reversal symmetry. So I will impose time reversal symmetry. And then a hardened phase is an example of SPT phase. Famously, the ground state of the hardened phase can be picturized by the collection of singlets or dimers or maybe bell pairs. So basically in this construction, we split a spin 1 into two virtual spin 1 halves, and these virtual spin 1 halves, they form a bell pairs. I always forget, is it inter or inter? This is the inter-site bell pairs. So this is the kind of picture for the ground state of the hardened phase. So I said something about quantum entanglement before. So to demonstrate the usefulness of the partial transpose operation to detect quantum entanglement, I first want to focus just a single bell pair and ask if there's entanglement. Well, we know that there should be some entanglement, but how do we quantify the entanglement? So using partial transpose, we can construct some sort of number or measure which can quantify quantum entanglement. So I have a bell pair, which is a part of the hydrogen thing, if you wish, and then I construct the density matrix. So following the definition I presented before, I take the partial transpose, which means in this case, we exchange these number 1, 0, or 0, 1 only for something sitting on the second entry. So here, partial transpose doesn't change this part of the density matrix, whereas for the last two terms, taking partial transpose changes these two terms into this. So we get the new matrix, partially transposed density matrix. So what people have noticed before was something strange. There's something interesting about partial transpose density matrix. So if you look at the eigenvalues of this partial transpose density matrix, it's actually not a valid density matrix in the sense that some eigenvalues are negative. In this case, there are four eigenvalues, but there's one eigenvalue which is now negative after taking the partial transpose. So it's some sort of condensed metaphysics language, some sort of response theory. So we take a partial transpose. If there is some quantum entanglement, your state will be battery changed, whereas if you have a classical state like this, taking partial transpose doesn't affect it at all. So here, partial transpose, the effect of partial transpose is so strong such that we now get the negative eigenvalues. So basically counting the negative eigenvalues which appear after the partial transpose gives some sort of some sense that how much quantum entanglement you have in the bare pair or in quantum state in general. This is called a PPT criterion. For our purpose, this story about quantum entanglement is related, but not exactly, because we are going to talking about topology rather than entanglement. So let me now move on to discuss topological invariant of hardane chain. And for that, we follow this work by Paulman and Turner. So they constructed topological invariant of hardane chain using tensor network, but here I phrase their invariant using the partial transpose operation. So their construction goes as follows. So I take the hardane chain which is living here, but then I take out the interval I. So then I first trace over all degrees of freedom outside of this interval. Then I get the reduced density matrix for this interval I, so I call it the law sub I. Then I partition this interval into two subintervals, I1 and I2. And with this bipartitioning, I take the partial transpose for the, let's say for the, for I1. So then I get the partially transpose reduced density matrix. So that's step three. And then I form this quantity, which is the trace of original reduced density matrix and partially transpose reduced density matrix. And then I will look at the phase of this quantity, and the claim is that the phase of this quantity is quantized as far as this I, I1, I2 are sufficiently large as compared to the correlation lengths of the hardane chain. And then the value will be plus one for topological attribute ground state, whereas for hardane ground state, it's minus one. So that's the construction. To make some, to give you some more intuition, we can also write this invariant using tensor network representation, where I represent my ground state using these smaller boxes. For the ground state, I have one column of boxes, which has one dangling physical spring index. There are two other indices, which are just budgetary there to encode the quantum correlation of this state. So using this, this topological invariant can be represented in this way, where you can sort of see there are four units of this, because each density matrix has ground state bra and ground state ket, and they have two such, two kinds of density matrices. So I have four columns, four rows, sorry. And then this trace and the transpose basically connect to these bonds. So this invariant, if you look at this diagram long enough, as it turns out, you can sort of deform this network, assuming it's a topological phase. And then this tensor network can be deformed into a, which is some interesting space time, which looks like this. So the tensor network, we want to view it as a space time pass integral, discrete version of space time pass integral. But this space time now is this peculiar space time. In the discrete notation, it looks like this. But this can be deformed into this space time, which is called the real projective brain. So it can be viewed as a two-dimensional plane with a small hole and this circumference, opposite points on the circumference of these points, they're opposite to identify. So that's what is called the projective brain. So that's the topological invariant of the hard engine. So it's a pass integral, so you can interpret the topological invariant as a pass integral on unoriented space time, which is a real projective brain. So why we are interested in this quantity to give you some more intuition, I want to draw an analogy to the topological invariant of the quantum hole system, which is basically just hole conductivity. So the idea is that we want to look at, we want to detect the phases of matter by introducing some sort of background, which I denoted x and a here, and then I just trace over or integrate over all degrees of freedom, which defines effective action for this x and a. And in this notation, I mean x is some space time, which can be torus or maybe a real projective brain, for example, and a is a background gauge field configuration.  And for the quantum hole effect, this phase part is given by the celebrated the chance I monster with quantized coefficient, I forgot to put I here, but this is a phase quantity. So drawing the analogy to this quantum hole example, what you are doing for the hard end phase is that for hard end phase, there's no even gauge field because charge is not conserved. But we are considering a background, which is the unoriented space time. And for the unoriented space time phase part of the partition function is quantized, either zero or pi. And for hard end phase, it's it's pi. So okay, so I think I'm spending too much time for the Bosonic case. But now what I want to do is to basically follow this strategy for other fermionic other cases, including topological insulators, and also KitaF chain, their fermionic topological phases of matter. So KitaF chain is a, I would say, fermionic analog of hard end spin chain. It's a one-dimensional chain where fermions are hopping on the lattice, and there's a hopping as well as this pairing term. And in this simplest model, the phase diagram looks like this. So they're topological phase, which exists when this chemical potential is smaller than the hopping and the pairing, whereas if the chemical potential dominates a hopping and the pairing, we get a topological and trivial ground state, okay? So skipping some details aside, of course, this is a system which hosts a Myrona fermions, and there's experimental interest, of course. But this is the very close analogy of hard end spin chain in the sense that ground state can be also written like this. So here, we take the physical electron, which we can split into real and imaginary part, and then in the topologically non-trivial phase of the Myrona fermion chain, KitaF chain, these real and imaginary part Myrona fermions, they form an inter-site kind of pairs, fermion version of pairs. Okay, so the question is, can we detect topology of the Myrona fermion chain by using basically the same technique as we use in the hard end spin chain, okay? So that is the question I want to ask. So this interesting complication for the Myrona fermion chain in the presence of time reversal symmetry, I want to impose time reversal symmetry. So then with time reversal symmetry, previous study suggests that different phases, topological phases in the Myrona fermion chain are classified by Z8 quantum number. So classification for the hard end chain was Z2, but now we should detect Z8 distinct topological phases in this business. So anyway, we want to follow as closely as possible the strategy we use to construct the topological invariant of the hard end chain, but then there's this issue, what is then the partial transpose operation which we used before? So partial transpose operation is very transparent for bisonic systems, but for fermionic systems, the problem arises because fermionic field of space doesn't nicely factorize in the sense that if you have a two fermionic operators, let's say here and there, even when they are far apart, they still know each other because of fermionic sign, fermionic statistics. So this actually complicates the construction of partial transpose operation, which constructing varied fermion partial transpose is rather complicated. So this is the first thing we tried to construct, and once we construct the fermionic version of partial transpose, we can then use partial transpose to construct the many body topological invariant for fermionic phases with time reversal symmetry. And as it turns out, people have looked at the definition of partial transpose for fermionic systems, but we found that the existing definition was rather useless for our purpose. The reason we noticed that was the following. So we looked at the entanglement property of the fermion chain. So by previous definition, I mean people previously looked at the fermion version of partial transpose essentially by taking the Jordan-Wigner transformation. So they take the fermion chain, but they convert it to bosonic system. Once you rewrite your fermion system as a spin chain system, you can use the definition, you can take the definition of bosonic system to define bosonic partial transpose. But as it turns out, it doesn't detect the presence of Myrana dimers, which I used to picturize the ground state of Myrana fermion chain. So the protein here is the entanglement measure, which is going to entanglement negativity. I will not go into the detail of this quantity, but it's something which is supposed to detect quantum correlation. This quantum correlation using the Jordan-Wigner version of partial transpose says entanglement in topological non-trivial phase of ketaph chain is actually zero, close to zero. If you are deep inside the topological phase, which is sort of very strange. So that's why we noticed that it is actually important to construct the partial transfer operation for fermions from scratch. So that's what we did, and this slide exists here just to say we constructed it. Details are, I think, I want to skip some details, but we can construct fermion version of partial transpose. And for fermionic systems, it is convenient to use expansion to define your density matrix. I mean any operator can be expanded as a polynomial of fermion operators. And then when you take a partial transpose, we add some phase to the matrix element which didn't exist for bosonic systems, which is important. But I think I'm going to skip this detail of the definition of the partial transpose, but I just want to say we really did it. So now using this partial transpose, less will be rather similar to the bosonic case. So this is basically the same as what we did for bosonic case. So we have a now k-tive chain living on this line. And then for the same procedure, I construct the reduced density matrix. And then I take the partial transpose for the part of this interval i. And then I consider this quantity, or the phase of this quantity. So as before, this is supposed to be a pass integral of fermionic systems living on an oriented space. And this really works. So here is the numerics of this quantity. So here, this is a phase, and this is the amplitude of this quantity, z. And let's just focus on the amplitude, sorry, the phase part. And it's plotted in the unit of pi over 4, which is 2 pi divided by 8. Okay, so once again, there are two phases, topologically trivial and the topologically non-trivial phases in the k-tive chain. So I will be focusing on this case. So in topologically trivial phase, this phase is basically just 0. But as you go into topologically non-trivial phase, this phase of this quantity is quantized in the unit of 2 pi divided by 8. So it's 1. So that means this quantity can detect z8 classification of the k-tive chain. Okay, so now I want to, for the last, I just want to present one more example, which is the topological insulator. So topological insulator is, there's some difference. Now it's a two-dimensional system as opposed to one-dimensional system. Another difference is that k-tive chain doesn't preserve a particular number. It still preserve even the parity of the particular number. But in topological insulator, a particular number you want is strictly conserved. So there are no two symmetries to talk about, time reversal and charge you one, okay? So then we have to construct topological invariant taking into account these two symmetries, okay? So, but other than that, construction is rather similar to the case of k-tive chain. So now I have a two-dimensional system which is wrapped into a cylinder, okay? And as before, I focus on a sub-regions of this cylinder. So now I have a region R1 and R3. And the other part, I just call them R2, okay? And then I first trace over this region R2 to get a reduced density matrix, which is living on region R1 and R3, okay? In addition to the partial trace, I have to decorate this reduced density matrix by adding this factor which is the, which twists the phase of the wave function along y-direction only for region R2, okay? So this is something I call partial U1 twist. So it's a kind of twisted version of reduced density matrix living on region R1 and R3. But then I will take the partial transpose for region R1, okay? And then I combine these quantities to form a, this quantity z. So there's similarity before. So the previous example was simpler because it's basically raw partial transpose raw and that was it. Here because of the extra U1 symmetry, I need to add this phase factor. And what it does is to produce, so as before, taking partial transpose, I basically simulate the passing to grow on an oriented surface. But because of the U1 symmetry, I have to introduce background U1 gauge field on top of this background spacetime manifold. The spacetime manifold is a crime-bottle times periodic S1. But this extra U1 gives you additional background, appropriate background gauge field configurations, okay? So these are the final things. So the topological invariant, if you compute it numerically, it's the phase part is either plus or minus one. So for topological insert, it's minus one. Okay, so I just put my summary here. Thank you for your attention.


The last time you said that you were more focused on things that are bigger than football, obviously the events with Breonna Taylor coming down in Louisville today and the reaction across the country. I'm wondering how you consumed that and how you've been handling that today. I mean, it's unfortunate, honestly, but I can't say I'm surprised, kind of new. When things take that long and they're trying to figure out all the process and they're doing all that stuff, usually kind of can tell what the bird is going to be. So I can't say I was surprised actually when we met with the Chief of Police a couple weeks ago that he had kind of hinted to us that that was going to happen. So we kind of, me and some of the guys that had met with them had already kind of knew what was going to happen. So like I said, I can't say I'm surprised. And as far as my comments going on not really talking about football, I've kind of had to change your heart a little bit because I don't think me not talking about football is really going to change things. I think the best thing for me is just to take action in the community. So I'll take football questions, man. Well, just if I could stay with that, though, if you don't mind, what actions have you taken since then? I guess, or have you had time to put a plan together for something like that? I know there's been a lot going on. We hadn't had too much time. I mean, the first thing I did after I'd spoken to y'all is we immediately went down to the Chief of Police and we had met with kind of like the surrounding area Chief Captains and we had to set up just a great talk, you know, kind of they kind of just stated their point of view on things. We just talked and, you know, had a real constructive conversation. Obviously, we're doing things like, you know, zoom with the Titan, you know, like I said, all along, I think affecting the youth and the in the future of this country is with our youth. So I think the biggest thing we can do is, you know, athletes and got people with platforms, you know, is talk to the, you know, the young kids that are going to lead the world one day. So, but yeah, like I said, I'm going to be working with the Titans closely and just looking to do things to get out in the community and help as much as possible. Thanks, Mo. Kayla? Hey, Kenny, I hope you're doing well, man. Just shifting some focus to some game talk this week, getting ready to go up there to Minnesota. What do you see out of their offense? I know that Kirk Cousins has struggled lately, but you've seen him in the past and have success. What makes them a threat? Yeah, I mean, the first two games have been whatever. But I know, you know, Mike Zimmer, coach team, they're going to be ready to play. They're going to be, you know, it's going to be like walking to a hornet nest when we go to Minnesota. Kirk Cousins, he's played some good ball. He's a good quarterback. He's made a lot of plays in this league. You know, so it's going to be a tough challenge. They got weapons, you know, with Dylan, their two tight ends, Rudolph, Erv Smith, you know, obviously, Dalvin Cook is one of the elite backs in this league, so they presented a great challenge. I'm excited for this opportunity. Hi, Joe. Hey, Kenny, I guess when the day is over for you after a game and I know winning is number one, but what are you satisfied with? What's a good day for you? When you watch film, what do you like to see and what kind of bothers you on day after games when you watch film? If it doesn't go well? Honestly, just execution, effort, the details, all the things that, you know, Coach Vareble kind of preaches. As I'm watching film, if I don't see those three things on tape, then I'm not happy. I'm one of those guys that I try to be a perfectionist. So even if I make a good play, I think of ways to make a greater play. Like if I get a PBU, I probably could have got a pick. Or if I made a tackle, maybe I could have knocked him back instead of him gaining a yard or two. Maybe my communication needs to be better to my teammates. Just because I know something doesn't mean, you know, some of these younger players know something's coming. So just the way I can influence a game and impact the game bigger than myself. Those are the things that kind of leave stress on me. But honestly, after this last game, I went straight to my son's black football game. I got in an Uber and went straight there. And I wasn't thinking about the game for too long. But then shortly after, I was already watching the film, trying to get it corrected. And just kind of following up on that. I mean, what's it like? How long, how long are your boys? Eight and five. And then I just had my new son, Kari, Onyx. He's, I guess, two weeks down the exact day, how many days it's been, but September 10th he was born.  And how do you, how do you handle your emotions? And I know it's fun at this age, but what's that like watching your kids in athletic competitions?  I try to motivate my son and kind of preach the same things that we preach here.    Are you complaining? Are you begging for the ball?   I was raised a lot different. My mom had me, it was all win, win, win, win, win. There was a lot of pressure on me from a very, very, very young age to, to accelerate everything that, that everything that I did. And I just want to make sure with KV and and in car that it's about mine, but at the same time as they grow older, just teaching them how to compete and be competitive and whatever you do.  Tron. Yeah, we talked before about how coming here has allowed you to be really utilized fully as a safety. That was something you loved about Dean Pease. Now that he's gone and then looking at this, this last game, yeah, like I said, you were all over the place. How has that continued to evolve as far as allowing you to showcase your all out ability as a safety? Yeah, I think the coaches obviously they're doing a great job of put me in a position to make plays. You know, my teammates being around me being having that continuity in the secondary and, you know, the linebackers and even the D line, just knowing everybody, it's really helped me develop as a player. It's been, you know, I just enjoy playing next to the guys. You know, I have a high standard for myself. Like I said, when I go into a game, you know, my main goal is not letting my teammates down. So I mean, I think that's the main thing that's contributed to me making plays is just the guys around me in the locker room, you know, in the coaching staff.  And then being used at times in the Blitz game, I know Logan, he did a really good job of timing at that. That's why he was so effective for you. What personally makes you an effective blitzer? I think a little bit of it's a timing. I think it's a attitude. And then I work at it, you know, whether it's working my hands, understanding protections, knowing what the office is trying to do. I'm studying guys. How do they block? Do they lunge?  I study all those tendencies. So for me, I mean, there's a plethora of things that go into each week of how I want to blitz. But I think the thing that starts out, the thing you look at the most is just your speed coming off the ball. I think that sets up a lot of different things in timing. Because if you're late, a lot of times, these quarterbacks are good in this league. The ball is going to be out their hands. So I just got to make sure that whenever I blitz, I'm going hard as I can because I'm not always blitzing as a DB. I understand that you don't want to be covering forever. So when I'm blitzing, I'm thinking about, you know, Malcolm, I'm thinking about KB. I'm thinking about Chris and Chris Jackson, J. Joe. I'm thinking about, man, I need to win and beat my guy. So my guys don't have to cover as long, you know, and maybe I'll be able to affect the ball and they'll be able to get a pick. Thank you. Chris Harris. Hey Kenny, I was wondering, I know you said your kid, your oldest kids are eight and five, so they're obviously too young to have, you know, a serious social justice conversation. But even at that age, I'm just kind of curious as to what what type of seeds of equality and positivity you're planting in them from the word go.    I mean, so we come from all different backgrounds, so there's no ounce of racism, none of that in our blood, because we, we're way, way, way too mixed to be, to even think in that way. But no, honestly, what makes it easy for me is just having my kids in sports.  Nobody really cares about, you know, skin color, race or religion. It's all about, you know, playing for your teammates and, you know, ultimately that, that goal of winning together. So just, that's the main thing for me is obviously, yeah, I preach to them that, you know, treat others how you want to be treated in all those key, key values. But being in sports is probably the best thing and the best way to teach those lessons. And I wish everybody could experience it. John? Yeah, Kenny, one, one nine football, one football for you on the, on the first, the Louisville situation.  You had a lot of team discussions and there's a lot of frustration. I wonder if you're, if you're getting some of that again today from teammates, you know, if there's any, you know, frustration level or team meeting scheduled in the same regard as it was last month.  I don't think we're, you know, but I think honestly everybody's just tired and, and it was expected. Like I said, nobody was surprised when the verdict came out. So, you know, obviously everyone has heavy hearts today. Everyone, you know, and I pray for, you know, the city of Louisville and everybody in that community that's experienced in these hard times. But no, as far as, as far as our team, like we've had our discussions, you know, we talk amongst ourselves. But I mean, nothing more needs to be said. I mean globally, these, these problems need to stop. And I'm praying they do. And on the football front, I know last week, some of the injuries resulted a lot of inexperience at the corner spots. I wonder how that affects you and Kevin at safety. You know, if you have to be more conscious of that when there's, you know, maybe one, two rookies are generally a lot of inexperience at the corner positions. I mean, the way I see it is, you know, one guy goes down as the next man up. It's an opportunity for a young guy to really go showcase his skills, get his opportunity to go make a play. I don't worry about it. You know, Coach Midge, you know, Shane Bray, they do a great job of getting everybody ready. And eventually, I remember being a young player, you got, you got to play to get better.  You can't, you can only emulate in practice what's happening in the game so much.   And I do that on a regular basis, whether it's a veteran or a rookie. So not much changes for me. But yeah, I mean, when I get excited when a young guy gets his opportunity, because I remember, you know, seven, eight years ago, you know, being that young rookie in the locker room, wide-eyed, ready to go and not wanting to let my teammates down. Starting to run short on time. So I got time for two more, Teresa. Just following up a little bit, Kenny, on those kids, Chris Jackson and Christian Fulton. Are you, what are you seeing from them out there on the field?  I mean, it's a weird year. Those guys didn't, you know, they didn't get OTAs, they didn't get rookie minicamp. They missed those valuable, valuable reps. So any expectations that people have, they need to be settled down a little bit because they didn't get all the, you know, they probably missed three, four hundred reps of certain coverages or in things we're doing.  Last one, Terry. Kenny, and back to the young guys again, I've heard lots of guys over the years say that, you know, when there's inexperienced guys out there that sometimes they themselves try to do too much to help them out, how do you kind of walk that fine line between helping them out and doing the job that you're assigned to do so that you don't get caught out of position? Like I said, first and foremost, I think every person on defense, I mean, the main thing we preach is doing your job. And as a guy that has experienced in this league, I think being able to also do my job and communicate and help guys be better themselves is valuable too. You don't want to sacrifice your game trying to tell everybody what to do. But at the same time, if you're willing and able and you're able to do it, I believe you should do it. And that's my stance on it.  I think with me, my knowledge of the game, I'm able to help other people around me and not just myself.  And that only benefits the team that helps us win. So whenever I can do that, I'll do it. Well, I got one last one. Jim, real quick, he's got to get going. Hey, Kenny, how important you think it is for guys to kind of know the players before them? I guess if you came here from the Saints, did you study up on or know about the Eddie Georges, the Steve McNair's, the Blaine Bishops, the Keith Bullocks, and do you think that's important for young guys entering a new organization? I mean, I think it is. I mean, I love ball.  I think it's, I think that's just part of ball. Respecting those before you. But at the same time, as a player, being your own person and molding yourself into whoever the player you want to be. But yeah, I definitely, I knew about all those guys before I got here, but that's just my, that's my love of the game. Some guys aren't the same. Some guys, you know, they play football and they don't really, they don't know too much about the past. I think it's important. I don't know. This is the game we play, the game we love, and knowing the history of the game is something that I've always, that I've always enjoyed. I love going back and I actually follow this NFL throwbacks on Instagram. That's why one of my favorite follows, just seeing some of the, you know, Hall of Famers or even guys that that were forgotten. They're really, really great players. It's really fun to see. So.


Today we're going to talk about the new crook and marker spiked teas and spiked lemonades Hey there and J route 22.com here with another kind of booze review And I guess it falls into the low carb keto carnivore category because crook and marker we removed Reviewed one of their product a few months ago. It was their spiked and sparkling seltzer that was a low low carb zero carb actually and And it had a Rithritol in it and it was we noted that it was really sweet And we had to actually use only a quarter of a can mixed in with other seltzers and we made our own little recipe And we found it pretty good and it was just really sweet and we sort of kept it on the fringe We didn't drink it all the time because it was more expensive Per can like a lot more But we discovered this I don't know how long they've been out But we discovered they have We found out they had a spiked soda. They had I think they had root beer and cola flavor, which we found were remarkably similar tasting to actual coke or Pepsi and root beer And they're pretty good. I can't find them around here recently But I found out that I got a spiked a box of spiked teas. They come in sweet tea lemon raspberry and peach as well as a I don't have the Box here, but the lemonade it was like plain lemonade watermelon raspberry, and I think blueberry And we tried them both they're eight packs and they're about 16 bucks in eight packs So they're about two dollars a can whereas you can get Smirnoff spiked sparkling seltzer for about 14 or 15 bucks a 12 pack which is a little over a dollar a can I wanted to add in post here that there's also a coconut flavor, which we may try Just once these are are profoundly more expensive, but anyway, I tried an eight pack of the Lemonades, and then I first and I said there are right there And they're flavorful and then I had this spiked tea which is if you had to pick between the two the spiked tea is Profoundly better. It's it's really kind of amazing in fact But there's a little bit of a caveat here, and this is going to prevent me from being a regular consumer of these of these drinks Number one like I said the same thing applies To these spiked non-carbonated beverages. They're extremely sweet. I couldn't imagine drinking a can of this straight It's so freaking sweet. This erythritol has an amazing sweet property to it that I'm not sure I'm Too happy about No, I'm wondering how this green is going to come out on my green screen.  I don't care about that stuff. I care about how it tastes and how do I feel the next day? So I down these and there's two important caveats to know about these crooked marker drinks number one the erythritol I'm not a hundred percent sure on what effect because I don't drink erythritol At all really I mean it's very infrequent And these have I think three can let me look here three Three grams of erythritol per can and if I split it up in half It's like one and a half grams per drink and like this right now is a drink That's half a can of iced tea or spiked tea and half a can of smear it off and then the rest is seltzer Plain unalcohol seltzer. I mean, it's a powerfully powerful drink. I mean flavorful drink. I Feel a little bit different when I eat or consume or drink Erythritol especially coming from someone who does doesn't eat any sugar any artificial sweeteners at all It does something to you it changes you and I can't I haven't put my finger on it quite yet I think it might make you a little bit hungry It might make you crave sweets and I don't know if there's any official studies out there Or not about it, but I don't think I'm going to it's kind of addictive to it, which is weird I don't think I'm gonna consume it anymore. I'll stick to my boring smear off seltzers and and and try to stick with that because I Don't like the way I feel when I'm when something is controlling me And I think the erythritol does something and oh, that's the second thing about you. They're so Smooth and and you just seem like just like a diet soda I used to pound diet sodas with the artificial the really lame artificial sugars are aspartame or whatever And I would pound them you drink more you drink more of these than you normally would with something That doesn't have the artificial sweetener. I can say that for certain So you drink more and that's not something I don't want to have something control how much I drink I drink when I an alcohol is it is addictive to begin with and you always have that one extra drink But this you drink faster and you drink more so I like the way they taste I think And that's not saying a lot if it's if it's something that's like a puppet controlling me and my mind and my body So they're more expensive you drink more and there's a suspicious kind of effect on your body So overall I would not recommend these things if you want to give it a try for yourself Make sure you haven't had any sugar or any artificial sweetener for weeks before you try it and let me know how you feel So that's it if you liked the video, please hit the subscribe and the button and all these other fruity things and See you next video


Alright you guys, what is going on? Welcome back to another video. Today's video we're going to be looking at the number 96 player, the 96th best player in the NFL of all time. It's the top 100 NFL greatest players.  So probably about 2 or 3 a day I'd assume. Although I might extend it for a little bit longer. There's going to be other videos put in here and there. Obviously with me training and talking about other things that are going on in my life. I hope you've enjoyed so far and I hope you enjoy the top 96 to come. So we've got Mel Hine, I believe. It's only a short video, 3 minutes long. Let's get into it. If you were picking the greatest players in Giants history on sort of a Mount Rushmore, you know you'd have Lawrence Taylor and you know you'd have Mel Hine. L.T. and Mel Hine. Giants. How old is this? The first Hall of Fame elections were in 1963. 1963, wow. When you look back over the first 43 years of NFL history, Mel Hine was one of the guys who was immediately plucked out as a charter member of the Pro Football Hall of Fame. Coach Steve Owen and his world champion New York football Giants will help us analyze the game as it is played today. Mel Hine, the greatest center in the league. Center. Giants built their franchise in the 30s and early 40s. He's a bit slimmer than the centers today, isn't he? He's demanding according to the dimensions that were used at the time. In the 30s, the NFL was in love with unbalanced lines and the guy who kept track of all that stuff was the center. What's the gap these daylights through? Do they not do that now? Oh no, they must do. The first door. Wow, the only center. Crazy. Nice, he played both positions. Good tackle. Yeah, nobody plays both sides of the field now, did they? Bang! Closed line. I would hate to have come out of a ball game and sit on the bench and watch him play. I don't want to be on the bench. I want to be out there and see the action. Mel Hine is not as well known today as Red Grange was, or as Nagersky, or the great players of that era. The pitch, the lateral. But in an era when Pro Football... It actually looked like he spun there like a rugby pass, believe it or not. Oh, the step! The big star of the New York Giants was linebacker Mel Hine. Mel intercepts a sit-lock control and runs like a half-back. And that's why he goes down with one of those... Oh, I'm glad I saw that. He's got pace. The only center, Mel Hine, the only center to ever win the NFL MVP. Wow, look at that. Oh, we're going to enjoy the next one. Larry Allen. So I want to say, if you have enjoyed this video, please hit that like button. If you want to subscribe, even better, there's going to be so much more content to come. And I'll see you soon. Peace out.