No better person to talk about this way than Tim Ord of the Ord Oracle Tim. How are you doing? Good. Thanks for having me on again. Absolutely. We're happy to have you. What are we taking a look at today?  Yeah, we got a lot actually There's a chart for I sent you another chart. I got that one. Yep. Charter. Okay. Yep that chart eight takes in place of chart four perfect Sorry, I'll be I'll skip chart one. This is kind of like a I've been showing this chart probably for the last month or better But it's the summation index again. We got a a bullish Well bullish confirmation of an intermediate term trend when this NYSE summation that falls below minus 700 Which it did back in October 27th and within two months it should rally to plus 1,000 and on December 27th exactly two months. It did have a plus 1,000 that predicts the next 12 months in general It could be longer than general should be an uptrend that didn't count You know There'll be some minor declines along the way and what I'm looking at today is is one of those minor declines So let's kind of look at that. What's going on? page or for a chart to And this is the daily SPX TLT ratio and So that's a segment down from the top the RSI is a 10-day RSI instead of 12 or a 14-day RSI just seems to work better And yes, they put it in my market letter This gets up around 70 normally you get short-term highs all those blue lines across there Our times when the RSI for this ratio got above we got at 30 or 70 plus 70 or higher And yesterday after I forgot was like 68 point something or almost 69 So that was kind of a worrisome sign even though the market could have pushed her a little bit more There's kind of a worrisome sign that were due for some sort of Correction and obviously that day that warmed that in my market letter, but I don't think this is anything Really to fret about and this the reason why if you look on Chart number three And you funny you bought the Vicks up. So that's what I'm what are we gonna be kind of looking at here? Acceleration basically the market I Know there's different ways at top but bottoms are a lot easier to pick than tops and this what's going on right now It's probably a short-term bottom. Is it today? You know, it's a good chance could be today But it's not a long-term bottom. This is short-term bottom And what I do is measure the acceleration of the Vicks So there's different ways of Panic panic only comes at bottoms. You don't get panic. You don't have a bottom So what you really want to see right off the bat is panic in the market and we get you measure with with the ticks You can measure with the trend. That's t-r-i-n or you can measure with the Vicks I'm sure there's some other indicators That also panic but I like those three indicators to look at panic and it only Panic only forms of bottoms. So Do we have panic in the market right now? according to the Vicks I Looked at the acceleration of the Vicks how fast that Vicks moves and so I got an RSI hooked up to it I have a percent volume or percent Bollinger Band hooked up to it Which is the second window up from the bottom and I have a rate of change and it's a two-period rate of change and This is our an hourly chart. So it's a short-term chart So we did get a when I made this chart a couple hours ago. The RSI is Almost 90 so anything above 70 showing it does show that the Vicks Was the accelerating at an usually high rate and all those times in the past That's those red lines across the chart at other times when the Vicks accelerated really fast with the Vicks Or the RSI 10 or the 14-period RSI for the Vicks got above 70 and also the percent Bollinger Band did get above 1.25 Today so we got a lot of panic in the Vicks and So this is an hourly chart. So it predicts that we'll probably have some sort of short-term low Let's go look at chart number eight. Yes That's that one to replace this chart number four. This is kind of a similar indicator But it's on the daily time frame. So you're looking at a daily Acceleration of the Vicks and you're looking at an hourly several Acceleration of the Vicks so the bottom window is the RSI 14 for the Vicks and has to get above 70 with 70.44 and I did this chart and The next chart above is rate of change is two periods on a daily part. It has to be above I think 30 it was actually 29.62 close enough And the next higher window is percent volume or percent excuse me percent Bollinger Band and it has to be above one And when it is a chart it was 1.37, but you only need two of the three indicators To reach bullish levels suggesting that you're near a short-term low Well, we actually had three of them there the RSI they were to do period rate of change and the percent Bollinger Band so This is probably and this is expiration week. Normally you get Normally expiration week the week before expiration week you get the weird moves It's kind of unusual to get a weird move during the expiration week, but I think we're getting it here So I do think we're probably at a short-term low But it's not on the bigger time frame If we end up down around 2% today 1.82 is put as we're talking If you get around 2% Declines normally come in clusters So what that means if the market does bounce here, which we think it will because it is till expiration week And we've had a minimal amount of get back to the gap area if not get back to yesterday's high and I think That may be a worthwhile top. I'm thinking back on January 31st, we had a selling climax at around the 482 area and I was thinking we're going to see that test of that selling climax Which is again? January 31st at some point probably this month, but I don't think you're going to do it this week You may do it before the month is out so later in the month, but our short-term basis here I think the market's probably at a short-term low and we may bounce possibly to yesterday's high and that much more and Then we'll probably build some sort of a top pattern and then and take a shot back down to 42 area and And there we'll probably find a base and start rallying again. So I don't think we're at a long-term high here, I think we're more of a Big consolidation where that consolidation is basically a I think I added up to around 4% Trading range that may be developing here where yesterday's highs probably resistance and the January 31st low is probably support Which is about 482 so also around the 5,000 4,000 there's round numbers, but we're around that 5,000 level so I'm thinking we're gonna have some back and forth around Perfect. Yeah, here to the music. Yeah, Tim. Please hang right there folks. We'll be right back with Tim ward of the oracle All right, welcome back folks This is Jacob Schup fill in in for Tom O'Brien, and we are live with Tim or of the oracle Tim are you still with us? Yep, I'm right here Fantastic, so we were just looking at eight which was the replacement for four. That was the VIX so Do you have anything else say on this one or do we need to move the chart? Do you have any questions? I'm just what I don't know is it the acceleration of the VIX and that's panic and That's what I'm trying to point out here We got enough panic in the market at least on a certain basis about the producer rally that may rally into Friday or something So but I think the bigger trend that we're starting a trading range for again That would be right above that 5,000 level down to 482 or not by 500 level 50 502 on the SPY's in the sport around 482 Yeah, I think we may bounce around in that area for a while I don't know how long but that does not in the bull market. I think the bull market I think we still in general have a 10% more to go before the year is out to the upside. So This is not You know at the time to be short other than a trade back down to 482 so Anyhow, do you have any questions or no and honestly Tim? That's why I love filling in on days that you're here because you explain things just so simply, right?  So Okay, well, we'll see if it works out My opinion for right now. We'll see how it works out. Sure But I don't think there's really nothing serious here You know that the serious thing would be if we didn't see any panics in in anything And you know, we got a trend right now 1.25 has been a lot higher today than that But you know, it's I like to see it higher and that may come on a close. I don't know but anything above 1.2 Down day is it leaves a bullet if we had a big down day the trend was say point eight or point seven That'd be a sign of trouble But that would probably mean we're going to go down until that trend starts to you know gets above 1.2 So anyhow, it's to me. I think we're we're okay You know market can prove me wrong for sure, but we can move on or we can discuss this more Yeah, why don't we check out we have on chart five currently unless if there's any questions, too You have for Tim guys in the den go ahead and message them to me and I can also bring them up to him as well Just throwing that out there for everyone and we'll wait for those to come in But we can move to chart five in the meantime if you're all right with that Tim Yep, okay Dev Actually, this is an inflation deflation ratio of Martin Pring bought this indicator I don't know how long it's been out that he's the inventor of this and well actually I use I don't know if he never used it this way I use it, but I use it with an RSI and this is the I think the daily sure Yeah, this is a daily. I'm also going to show a weekly time frame, too But you know that the second window down from the top is then the daily inflation deflation ratio in the top window Is the RSI for this ratio and works the same way but moves any indicator moves too fast you quick one direction Usually you're at Most time either higher or low on this case. I took the RSI anything below 30 on this ratio So when this ratio really dives down is when you get the signals in the bottom window is Gdx next window up to the XAU when we actually got a signal last week on this indicator and So even though we're down 5% today, they're about This indicator can be off a little bit. You're like a week or so So I don't think we're starting a big decline here But since the daily inflation deflation ratio is bullish and it was a bullish late last week, I think we're still okay because Especially with the Gdx a lot of times Gdx trolls a lot of these indicators, but if you flip to chart 6 This is the the weekly inflation deflation ratio and it's also producing a signal. It's pretty rare To get the daily and the weekly to have signals at the same time And this is one of those times that's doing it and this chart goes back to 2016 and shows all the times the RSI of the inflation deflation ratio getting below 30 and turning up which it did last week and And even though we're all 5% I think there's just kind of a shakeout going on here So I don't think this is a starter decline I think we're pretty much ending of a decline and it works pretty well It also works when the RSI gets above 70 on this ratio Especially on a weekly time frame, which is the red lines across there you get some sort of a high and So I think we got we had last time we got a signal was in October Now we're getting another one and pretty much close to the same level even though we're down a little bit from it matter of fact this If you look at Gdx really haven't changed much from last August things just Going sideways here and it's still generating bullish signals It was generating very signals going sideways. That'd be a problem But we're not we're generating the bullish signals. So I'm still thinking we're probably basing in here And if you flip to chart 7 Yes, and everyone's asking about the Gdx as well in the dent to so Okay, yeah, this this is kind of unusual. I should probably took this chart back But we're down. I don't know why I did this chart around 5% or better And both those indicators normally when you get above minus 10, which we did a couple of days ago On the way out of the bottom one August you'd find it the bottom one was Gdx Updown volume with an 18-day average next window up as Gdx advanced decline with an 18-day average and even though the Gdx has moved down this indicators moved up and So there's a positive divergence going on But the rally really doesn't get going until this both indicators or at least one of them gets above minus 10 and stays above minus 10 What is unusually here these two indicators are not really backing off much Blow minus 10 even though we're off 5% today. So I'm thinking it's just it's kind of a shakeout thing going on I don't think On the bigger time frames. This is like it's going to continue down. I'm thinking especially with You know if the weekly was more near a cell signal than a bi-signal I think that'd be worrisome, but that's the opposite. We got the daily and the weekly both the generating bi-signal We're still down 5% today, but that kind of What those two indicators the RSI probably today will be even lower than it was a couple of days ago Take on that. Yeah, this is probably still low. So How low is low where's the thing ending and you know, I assume would be right around in this vicinity because I'm not seeing a big I see a positive divergence, especially on this indicator on Chart 7 as the market moved down this indicator was going up showing that Actually the advance the client is getting stronger and they actually up down volume is getting stronger So there must be something in gdx one stock that's doing most of the damage and they're probably was telling me So we'll have to wait and see. Yeah, and really that was gonna be my my question too You know when we've been speaking it's that's what we kind of talk about right the gdx is just not moving a lot It's not it doesn't have a lot of action and then you know today We do have a down move been something about 5% on on some volume, right and I was gonna ask what would Exist essentially that could indicate that this is actually a bullish signal, but you actually did answer that so thank you Tim You're right. Absolutely. Thank you so much for coming on. We enjoy it every time Guys, that is Tim or of the order Oracle. That is word hyphen Oracle comm go give it a check out Tim. Thank you so much for joining us today All right. I'll see you winter. See you Thursday. See you Thursday Tim. Okay folks. Stay tuned. We'll be right back


Cross disciplinary project, we being the computer science students are trying to address the problems which mechanical engineering students face while solving their computational fluid dynamics problems. So actually they use C++ based open form software which is an open source software and it contains a rich set of numerical solvers, okay, form transfer field operations and manipulators. So actually what open form is based on C++ and for a newbie like very, very newbie person in the field of mechanical engineering, it is not the best way to start from C++ APIs. It might get tough if they don't have the proper C++ background, it might get tough for them to use open form. So Python flu addresses that problem. It provides an easy interactive Python interface to open form C++ reference APIs. So actually that was our main aim for the project, main motivation of the project. Actually Python flu was built five years ago and it was built according to open form 2.1.1 version and now the open form has grown drastically from 2.1.1 to 4.1. So we are trying to revive this Python flu package to the current version of open form. So Python flu needs two packages installed before we install the Python flu. It is one is conflu which is a common configuration package. If we run that package we can be sure it installs all the dependencies which are required by Python flu in the system and the second the managed flu what happens is the biggest limitation of open form C++ object solvers are if any one of the sibling object solver object dies unexpectedly then the whole solver crashes and what happens is many a times the simulation is running for six or seven hours. So if that rare incident happens then the whole simulation is gone for nothing. So managed flu provides a C++ layer of managed open form objects. So we need these two things conflu and managed flu for before installing Python flu. So why we cannot allow the null pointers the null solvers is because in Python we cannot afford to have those C++ null pointers. It can be deadly nightmare it can cause any system problem. So that managed flu is required. So while managed flu was built it was built according to keeping in mind the structure of open form 2.1.1 and Ubuntu file structure of 12.04. Since then the Ubuntu file structure has changed drastically also the open form has changed some of the header files some of the source files drastically. Some are totally removed some of them are merged into the other source files some of them are renamed some of them are relocated. So we try to do that thing that making this Python flu compatible but the main problem we encountered was this is the structure for open form 2.1.1. There is a particular reference header file called porouszone.h and mrfzone.h which has some specific fluid dynamics related task which we don't know yet because we have we have we are given a chance to abstract this project but the same mrfzone.h does not exist in open form 4.1 and this is just one example. So we tried to make the new mrfzone.h in open form 4.1 to make it work so we tried to take that mrfzone.h in current open form and make it work with Python flu. But what what has happened is since last five years the constructor for mrfzone.h object has changed from one parameter constructor to four parameter constructors and since we are computer science students and we don't have enough background in fluid dynamics we don't know what to do about those three uninitialized parameters. So that was the main reason that our project was got blocked multiple referenced fields. So we we just know the main abstract thing. We don't know the exact details and our our mentor professor Prabhu also said that you don't need to go into details because this this is not going to help us anyway. We have to just we are just given requirements and we have to make the software. So we instead we tried to do this in form extend 3.2. So form extend is a family based on open form 2 series. So we thought that since this this changes were untraceable we thought that form extend 3.2 might be a better way instead of open form 4.1. But in the form extend 3.2 you can see that these files are present. But again that one parameter constructor is sent to two parameter constructors. So we went through all the logs 3000 to 4000 lines of log while we compile this open form it takes six to seven hours of compiling plus this managed to also take one to two hours of compiling. We are mentor set set and went through whole logs but we could not find any proper reason. So our project got blocked there after five to six weeks. So immediately we changed our project to automated parameter variation in any CFD system computational fluid dynamic system and real time plotting for those systems the parameter plotting for open form. So open form was two point something five five years ago four point something yeah no no no the open form 4.1 is like working correctly. Because we could not yeah no no no actually there is another layer of python package called pyfom which does many great things like changing the dictionary files all the CFD system. The python flow was python APIs but pyfom is just a container for open form it just runs the open form solvers as its sub processes it does not care about how is it going to handle those C++ APIs it's it's just going to run them as a sub process. So pyfom does great things for us it plots the data real time there is a thing called residual in fluid dynamics computational fluid dynamics as we are using the numerical solvers we are committing crime the numerical crimes like we are we are bound to have some particular number of digits to represent as our mantissa and in floating point numbers we cannot we don't have the big size to store the exact number so we are committing numerical crimes. So it is bound to produce errors so those due to those errors the solver might sometime diverge rather than converging to a single solution it may diverge so those results are very important while the while one student is performing the simulation. So on the fly pyfom allows us to plot those results. So what we have done is also there is a thing called there are some some parameters like viscosity relative tolerance if you change those parameters the system the system might get some in some way optimized. So we need to change those parameters for a given range of value and save those plots and try to analyze them that for which value of parameter the system is going to be optimized. So we have tried to automate this thing rather than any CFD student changing those dictionary files the the CFD dictionary files are just a file representation of the system parameters initial values and the other things we have tried to automate the changing parameters also we have tried to save those plots and put them in a tech file directly no no optimization in the sense for a given parameter if no no no in any physical system for some some contour for a particular value of parameter the system might behave optimally. So we are to guess though guess that range and in that range that we have guessed no no no the the CFD student will give that as input and will save the plots append them in a tech file and generate the automated report for them. So that's the work we have done in last week also there is a working demo for that our so we also support real-time dictionary changes see in the the parameters are stored in nested dictionary format. So we have stored them as a graph in where each internal node is a nested dictionary and we have tried to search that if the parameter exists in a graph or not and we have tried we have used the depth-first search algorithm for that and change its value and this is our live demo. I think it's okay if you don't show the demo okay in your particular case it's okay I'll tell you why none of us understand anything about fluids okay whatever you show is going to be going to be a bouncer okay and I completely believe you were the first person who does not need a presentation.  Thank you sir. I have done a course in fluid dynamics. I have also done fluid dynamics I have forgotten everything about it. So there is a ICO foam there is a solver called ICO foam for which stands for incompressible This is our script PyFoam underscore automated we are changing the end time for the simulation from the two to three. So it will start the simulation it will plot those things in real time if the simulation is carried for a long time for say for a two hours it will be plot real time. These graphs are saved in a tech file which I have just closed and I will compile that tech file the PDF will be generated which can be later used for analysis of the simulation and this is the compilation of tech file and that was for end time simulation we can change the tolerance which we allow for numerical errors. So in the next example I have changed the tolerance which command yeah which command yeah the first PyFoam underscore automated.py is my script yeah which uses PyFoam and some my some algorithms which help me to get those parameters and change those parameters while the simulation is doing. So this is the first thing is my script the second thing is the file there may be some parameters like viscosity of the system yeah yeah because it's the need no no the for suppose the for viscosity from two to three two to three in the interval of point one you want to observe and for which viscosity the system behaves optimally then my script allows you to do that yeah that's automation for parameter variation yeah but for yeah so that's the second would be the files name which I want to which the parameter is located in which I want to change the third thing would be the total path that these are nested dictionaries so for that file in the solver dictionary there will be a key called P it would be in itself a dictionary which will have the parameter called tolerance I want the tolerance to be in 10 is to minus five to five into 10 is to minus five at the intervals of 10 is to minus five so I'll do that iteration on the go using the icofoam solver of open form so if I in this case I have typed the wrong parameter because it is solver slash P slash tolerance so it will give me the error and when I type the correct path it will start the simulation so it's real time just the parameter changes the lots will come on the fly yeah the backgrounds are the logs which open form generates for us to see what is the pressure value what is the velocity value what are the current numbers and etc so that was our project then the future word there are some parsers which I can make for particular dictionary files also I can add specific commands for some specific open form solvers and I can make those report very much interactive so that was our project any more questions if so actually the parameters are located in a very nested dictionary so I have made a graph like representation for each internal node is a nested dictionary and leaf nodes are the single key value pair so for that I have generated all kinds of corner test cases to check whether whether a full path exists or not suppose I given system slash p slash some parameter name and if that path does not exist then I'll produce the false error that parameter does not exist so I have tried to cover the whole depth first search test cases for that thank you


So, how we describe the pressure of a gas as it depends on its temperature and its volume differs depending on whether we believe the gas might behave ideally or maybe whether it might obey the Van der Waals model or in fact since those are both only models and there's the actual real world gas has its own pressure as a function of V bar and T that isn't perfectly described by any one of these models. Regardless of whether you were using a Van der Waals model or a more complicated equation of state we're often interested in the fact how ideal in fact is either the model or the gas itself. So we can define a quantity that we can think of, I'll give it a name in just a second, but we can think of it as a description of how ideal the molecule is. If I say what's the actual volume of the gas divided by the volume it would have if it were an ideal gas. So the name for that quantity is something called the compressibility factor which is a somewhat unfortunate name because we're usually not explicitly talking about the compressibility of the gas when we describe the compressibility factor but it's most useful to think of it as this measure of the ideality. If in fact the volume is exactly the same as the ideal gas law would have predicted then if we have Z equals one, V equals V ideal then the gas is behaving perfectly ideally and that also means let's go ahead and say if it's behaving perfectly ideally then PV equals NRT works just fine. In fact if I rewrite the ideal gas volume as pressure sorry not pressure as RT divided by pressure so I've just used the ideal gas law to rewrite V ideal as RT over P if I clean that up a little bit moving the pressure to the numerator. Another way to think about the compressibility factor is it's the ratio of PV bar to RT and again if the gas is behaving ideally PV is equal to RT the volume is equal to the ideal gas volume and the compressibility is one those are all identical ways of saying the same thing. On the other hand if the compressibility factor is smaller than one because this ratio is less than one because V bar is less than V ideal the gas takes up less volume than it would have if it were behaving like an ideal gas or in this case PV bar is less than RT and of course the opposite is true if the compressibility factor is greater than one that means the gas is taking up more volume than an ideal gas would and PV bar is bigger than RT. The first of these cases the volume is smaller than the ideal gas volume that happens when the most important deviation from ideal gas law is the attraction between the molecules. The molecules attract themselves occupy a smaller volume than they would have that PV product is smaller than we expect it should be. On the other hand when the volume is bigger than what the ideal gas law says is because the molecules the deviations are driven by the the finite volume of the molecules so it's making them take up more space than the ideal gas law predicts they would. So one thing that the compressibility factor is useful for is a prediction of whether or a measurement of whether it's the intermolecular attractions or the finite volumes that are dominating the deviation away from ideality and we can see that a little more explicitly if we bring up a graph of what the compressibility factor looks like so let's go ahead and add a graph here so this is a graph for a real gas this is real data for nitrogen at various different pressures measuring the compressibility factor z at a particular temperature of 200 Kelvin so the flat line here z equals one shows what the compressibility factor would be if the gas behaved ideally and we see in fact that the compressibility factor is not one it starts out at one and it's no surprise that at very low pressures at pressures near zero the the gas doesn't behave does in fact behave like an ideal gas at low pressures we expect gases to behave ideally but as we increase to pressures of one or two or ten or all the way up to 50 or 100 bars 100 atmospheres worth of pressure we can see that the compressibility factor has gotten much smaller only about 80 percent the volume is only about 80 percent of what the ideal gas volume would be and for this type of behavior what's going on as i change from let's say the ideal gas where i've got molecules in a box if i've compressed the the gas down to a much smaller volume the main differences the molecules are now much closer to each other than they were over here so there's closer to each other means they can interact more favorably and more strongly with one another so the effect of the intermolecular attractions has become more important so that's what decreases the compressibility factor but if i continue increasing the pressure up to 200 or 300 then what i see is now i've got the molecules packed so closely together that they're almost overlapping and on top of one another and now the size of the molecules has come into play and they've started to to bump into one another so that's generally what happens both at 200 kelvin as we see here also at at higher temperatures like 300 kelvin is at first the attractions between the molecules dominate and then later on the finite volume of the molecules begin to dominate and notice that at the higher temperature of 300 kelvin the effect of the interactions is is weaker than it was at 200 kelvin and that's for boltsman type reasons the interaction between the molecules is relatively weak and at temperatures of 300 kelvin thermal energy is more than enough to break those molecules apart fairly often so the effect of the intermolecular interactions is not as strong and in fact if we go to even higher temperatures of a thousand kelvin we see that the effect from the intermolecular interactions has disappeared completely and the only deviations from ideality that we see are in the positive direction so it's only the finite volume of the molecules that is affecting deviations from ideality and at these high temperatures the weak interactions between the molecules are not terribly important so that's an introduction to this idea of the compressibility factor and both this graph and this way of understanding that the compressibility factor might be sometimes lower than one because of intermolecular interactions or higher than one from finite volumes and we do in fact see both of those behaviors in real gases that brings up the interesting questions of what happens when coincidentally or otherwise those deviations from ideality happen to exactly cancel one another and that's the topic of the next video lecture.


How about this two color RPA CJ shroud there we go 11 of 50 let's go CJ shroud That's what we're looking for. That is what we are looking for Let's go Like that of course Let's go Jeremy as nasty box three


Hey there, Savlings. Welcome back to Esoteric Moment Today. I have a book review for you. It is Jailbreaking the Goddess by Lesara Firefox Allen. One of the things I love most about Druidry is that there is freedom to interpret and use language that fits your relationship with deity in the best way for you. There is not a dogma about a certain group of gods that you need to use, that you have to follow gods that there's just so much room for exploration of deity in Druidry. Because I was raised Catholic, one of the things that really drew me to paganism when I first started exploring it was the concept of goddess and having a more female archetype to work with in my spirituality. That was very empowering to me and even now as much of my practice has really shifted to talking about deity in terms of an animist point of view, the concept of goddess is still very powerful and that archetype is useful when doing ritual or working with groups, certain magics. It's still something that I call upon so a little bit of a hodgepodge work in how I interpret deity. Most pagans have heard of maiden mother crone as being aspects of the goddess. This book adds two more archetypes to that idea and mixes the maiden mother crone in such a way that the goddess interpretation reflects better how our lives as women in this world go about. There are different elements than just maiden mother crone in our lives, so it seems strange to have a goddess that doesn't reflect the full life of a woman and also the maiden mother crone doesn't really fit in well to the mythology and stories that we have of goddesses. The goddesses that we worship are more multifaceted than just three archetypes and this book attempts to kind of draw out what those other phases of the goddess could be like. Of course, you can't talk about feminism and goddess without also talking about gender, gender identity, that inherent transphobia that we have in our culture and this book starts out by talking a little bit about that. Now, those aren't issues that affect me personally, so I'm not an expert, of course, and I would strongly encourage you if that's an issue that's close to home or you're looking to research more. Definitely read this book with a keen eye looking for things that, you know, maybe don't fit the way our culture is now starting to talk about deity. So there is a chapter that addresses those concerns at the beginning of the book. Maybe read that first before you decide to purchase it, if that is something that is important to you. The book begins by going into the five archetypes as the author sees them. I will do my best to pronounce them, but pronunciation as we all know is not my strong suit. So the first is femilla, which is more like your inner child, that beginning stage before maiden goddess. The second is the potens, which is more like the maiden, this potential full of waiting expectation. The third is creatrix. This surpasses the mother archetype by leaving a more all encompassing view of the creative business, families, all the things that a woman can create in their life, all the things that we have read and experienced with working with goddesses bringing to life. There's just more room by calling that a creatrix instead of just a mother. Then there is the sapientia, which is kind of that golden time between whatever project, whatever family you brought to life is kind of on its own. You have this period after that, before retirement, maybe a little bit after retirement, before you're an elder, before you're experiencing lots of aging effects in your body, where you have amassed tons of wisdom. You have experience to put that wisdom to good use, and you have more energy to actually do something with that. So this book adds that between mother and crown. And then finally, it calls Antiqua the final archetype of kind of crone, the elder with lots of wisdom, a bit closer to the gateways of death and the other worlds. There's wisdom there, and what that role then brings to our community. The second part of the book talks more about what if we envision relationship with goddess in this new five archetype way? What does that mean for our ritual, for our magics, for our groups? And it talks a bit more about that, and it definitely gets a little political. So if that's not your cup of tea, this is not the book for you. But I think many people who are interested in goddess worship, who are interested in paganism will find that to be enjoyable and lots of interesting thoughts there. The book is easy to read. I like the author's tone. It was not super conversational, but still felt intimate and honest, not too dry or anything like that. I will say there are a lot of journal prompts kind of hajpaji in between all the sections in each chapter. And eventually, I became quite annoyed with them. It could be just because of the amount of pagan how-to-e books I was reading at the time, but yeah, it wasn't my favorite part. I think the real value of this book comes in pushing ourselves to keep innovating and experimenting with our own thoughts and our practices. It's easy when we are overwhelmed or at least on autopilot with our daily lives to kind of set whatever we've figured out in those first stages of exploration or the second half of our training or whatever to kind of coast on those ideas. And this is a prime book for those who are looking to shake things up a little bit more or to kind of dive further in. Often in Druidry we talk about spirituality and your life as a spiral. You are constantly revisiting the same ideas and thoughts and feelings, but from a slightly different angle. There's a little bit more for us to discover in every turn of the spiral as we get closer to ourselves, as we get closer to the world and the purpose here. Universal flow, whatever you want to call it that we're centering towards. I'm less concerned about where that center is and just curious about the way our perspective changes as we spiral around these ideas. And this book is an excellent aid on that spiral as you're looking at goddess in a different way or exploring deity in new ways in general. Maybe you haven't considered goddess worship or working with a specific goddess or even what that would mean in your practice. This could be a really great read to kind of shake up your thoughts and try something new on for size. This is a definite check out of the library. I think it's going to be harder for most to justify keeping on their bookshelf as like a reference book. However, it has managed to stay on my bookshelf through a couple of purges. So it's holding up better as a reference book than I first originally thought and it might for you as well. In the comments, tell me what you think about the maiden mother crone archetypes of working with goddess. Are you intrigued by having two additional archetypes or is your relationship with deity so far removed from those archetypes as it is that adding more is kind of irrelevant? Tell me your thoughts in the comments below. This week's sapling shout out goes out to someone on Instagram, WayDJack, and they comment on my profile a bunch, but mostly because their profile picture is gorgeous. You should go check it out. It's like two trees and the owen flowing between. I don't know if they did it themselves or if they're using somebody else's art, but I really love that piece. So you should go check them out on Instagram. And if you want to be the next sapling shout out, definitely follow me on Instagram at esotericmoment or comment on videos here on YouTube. That's how I get to talk to you and learn a little bit about what you are enjoying in Druidry, your practices, books, all that jazz. Thanks for watching and as always, may you find peace in the sacred growth.


Well, I was really very pleased if the girls came back in good shape. Freshmen typically are all going to come in shape because they're scared. They don't know what to expect. The returners, their spots open. And so if they want to win that spot, they need to come ready. And with two a days and three a days, if you're sore and that's going to hinder you, that's tough. You know this was coming. So the kids that are dedicated and pleasantly pleased with how everybody came in shape and were able to get a lot of work done. We have had a really good rivalry with Salisbury and have played them three times over the last two years. So two years ago we played them twice. They just happened to be at the same tournament. So last year we played them once and did not play well. So we definitely will be ready for Salisbury. The girls look forward to that. They know a lot about each other and some of them are good friends in high school. So they're really looking forward to playing Salisbury over the weekend. We know we had the target on the back but we really don't talk about it at all. In fact, we're talking less about winning and more about team chemistry and bonding this year than anything and any other year I think we need to re-establish our culture when we've had some leaders graduate and re-establish our culture and how we're going to treat each other. What is it that's important to us, our core values as a team and how we want to compete together as a team are the two of the things that we really have talked a lot about. Just like last year if we can get that win against Messiah, it puts us in good position for the rest of the season. Messiah, we think is going to be one of the top teams in the conference again and you always will like to get that first conference win. When you have a second team all-american returning, and everybody knows Annika Schwartz, so of course she is a huge part of our offense and our team and our passing and our defense so and Mariah Savage who was honorable mention all- American last year she looks very good in practice and Victoria Prokic will be back and she was honorable mention all-conference last year but I think after she got that freshman year under her belt I'm looking for her to do a lot of things there's so there's so many Joe you know Katie Leffridge came in in fantastic shape and she you know is really stepping up to help us in that outside position and Chelsea Ireland and Elb and Lauren Jan look really really good in the middle and we've got three setters that are really competing to see who's going to be who's going to set who's going to set this year and so that's yet to be decided so there is you know and and then there's Lauren Weaver you know another senior right side so there are so many which is I which is part of our six you know Anika's not having a good day it's okay you know we've got a lot of other people that can step up and that's the strength of our team now I didn't even mention I love our Diana Bradbury was honorable mention all-American as a sophomore in all region as a junior and she's being pushed by Megan Ren and sophomore and freshman Sarah Brigham so I mean it goes all the way down the line now we host my host Messiah on September 6th sponsored by the president's office that's our first big home match and we're really looking we're really looking forward to it we're so athletic and so entertaining and fun to watch and our games are free


Three fast facts about Marquette University. We're home to boards, goblins, and elves? Yes, you heard that right. Did you know Marquette Rainer Library is home to the J.R.R. token collection? The collection includes original manuscripts and drafts of three of the opera's most celebrated books. Their history on campus dig back to the year 1420. St. John of Arc Chapel, arguably one of the most beloved sites on campus, was originally constructed in early 15th century France. It was rebuilt in the heart of campus. Haven't checked it out yet? Attend St. John of Arc's weekly Tuesday night mass at 10 p.m. We have a big Marquette family. A network spanning all 50 states and many parts of the globe, our alumni community has rallied to support our students and our campus through the Time to Rise campaign, which has surpassed its goal of raising $750 million. It goes without saying that we love our alumni. Want to learn more? Visit marquette.edu.


Can you hear me? Oh, yeah, welcome back. So let's continue. Let me quickly review the first episode. So we were discussing infrared structure of gravitational theory in Minkowski space in four dimensions, or more generally, theory with massless particles discusses three different topics and their relation. And then we focused on the simple toy model, which was the analog of this 2D icing, which seems to capture some of the things and would be helpful when we move now to the most general case of asymptotically flat nonlinear dynamical spacetime. So the toy model was that we discussed the Penrose diagram. It's global aspect, so we have null infinity. We have some sources, which are particles coming from, say, null infinity interacting at a point and going to future null infinity. They start in some directions specified by initial momenta and end up in some final dimension. So this is just a stress tensor, which enters in the right-hand side of Einstein equations. And then we solved for the metric, very simple exercise. And we focused on the behavior of the metric close to the null infinity, which corresponds.  So this is a constant U. Looks the time U runs here on scry from minus infinity to plus infinity. And V, which is T plus R, which also run from minus infinity here to plus infinity here. Then we found that, so this kind of source, which is a typical source when we consider gravitational scattering problem, being gravitational scattering problem, we fixed the initial data here and we look for the final data here. So we found that if we focus on the value of the metric in some observational direction labeled by unit vector n, that the expression was very simple. And moreover, we had this overall change, which is called memory. And this was related in a simple way to famous Weinberg soft factor. That was lecture one. Now let me add a couple of comments about that. And first one is that notice that if you observe the change or this metric in some direction n on the sphere, it's a very large distances. R is very large. You cannot see explicitly this other particles because they're very far away from you. They're piercing the sphere in other directions. It's like celestial sphere away from a gravitational scattering event. You cannot see what's going on. We are sitting at one point on the sphere. That's where we have our detector. Nevertheless, this metric explicitly depends on all the momentum which is piercing the sphere in all directions. So this effect in a sense is very infrared. It is sensitive to the particles, which are even far away from you. It's not local on the sphere. Second comment is that you can, as an exercise, as a very interesting exercise, you can generalize this computation with a retarded propagator to d dimensions. And you will find that in d dimensions, the picture is the following. That you have a radiation that appears at the order 1 over r d over 2 minus 1. In d equal 4, it's just 1 over r. And you will find a memory that appears at the order 1 over r d minus 3. Notice 1d is equal to 4. It's the same order. And this is related to many special things that happen in four dimensions. In high dimensions, these are different orders, and it also leads to many complications. Also, you can compare your result with a recent paper by Wald. They say that there is no memory in high dimensions. But they look at this order. So if you look at high orders, there is a memory. OK, so these are two comments. Now let us move to some other interesting aspects of this toy model, a very simple one, which is, namely, let us ask, what is the asymptotic behavior of this metric at the boundaries of SCRI? So what are the boundaries of SCRI? The SCRI is labeled by this time u and a sphere. So we can take this time, if we take u to infinity, let us denote it i plus plus. When it goes to plus minus infinity, we will denote this as i plus plus minus. Similarly, on the SCRI minus, taking the time plus minus infinity, we will denote i minus plus. So this is on the diagram we are approaching these points. This is i plus minus. This is i plus plus, i minus plus, et cetera. So notice we started with a metric, which is completely irregular on a spatial slice. You can find this metric everywhere you like.  We can explicitly find everything. You will find a surprising result, which is, well, maybe it's surprising at first sight only, but you will find that the metric on the future, on the i plus minus, so when you approach past on the SCRI plus here, is equal to the metric when you approach from the SCRI minus, which is untypidally matched. So there is a flip on the sphere. That's a crucial thing. And what happens is that we have a completely smooth metric on a spatial slice, but when we go to SCRI plus or SCRI minus, we first take a limit r to infinity. And then we're taking the limit. This is first. And then we're taking the limit of u going to approaching this point. In a physical space, when you're doing this order of limits, two points never come close to each other. That's why it makes a total sense that you might have thought this is completely crazy. We started with a smooth field, and now we are getting that, first of all, the limit exists. So it makes sense to talk about this limit. The field takes finite value. And second of all, we find that they are untypidally matched. So this is a, you can explicitly compute and check in this example. Also, you can, well, as an exercise or as a side comment, there is a famous, let me just write it, for electromagnetism. If you somehow feel like it, you can write the value of electric field similarly. It takes a form which satisfies the same, the same untypidal matching condition. So on i plus minus, it has a similar form, similar to this, with a soft factor. And on the other side of i naught, which is a special infinity, it's the same formula, which is, but you flip, you flip, well, let me write it just minus n. Yes, thank you very much. Please ask me about notations. I'm introducing so many of them. So ui is a four-velocity of a particle, if you remember. It's a four-velocity of a particle. Over here, where you can consider sources instead of particles with a mass, some charges, which come, again, come and go. And n is, again, observational direction. And n is a four-vector, one, and the direction in which you observe. Okay, so that's surprising, the upper. So yes, in this model, this is a result of a computation. So we start it with a source, we find metric everywhere, it's completely smooth. But then, when you take the limit first, you're going to scry, you read off the value of field and scry, and then you discover that they are typically matched. So one of the, well, as we will review, this is one of the, I think it's a main ingredient in the paper by Streminger, which is, I guess, realization, or that's a correct thing in general. So even though we did this thing in a very simple model, and as far as I know, apart from these arguments, like this kind of boundary conditions, they respect Lorentz invariance and they work, so they lead to correct predictions, there is no really mathematically rigorous derivation of antipodal matching in a generic nonlinear problem. So if you wish this is, at the moment, in our general treatment of asymptotically flat spacetime, this will be a crucial insight in all the conservations, all the conservation laws, super translation, super rotations, it will come from the fact that we match things here. So this is a really important step, and this is called antipodal matching condition. So, I'm sorry, say again? No, I think that if you will specify the some cache data here, we will find that this holds, yeah. Right, you can think about it as follows, for example. Let's take the spatial slice, there is some cache data. You can evolve it forward or backwards. So there is one initial data that is specified that specifies everything. And now, if you wish, you take this initial data and you go to square plus and square minus, and in general, these are different things. But then when you move this point further and further, you discover that what survives is just the tail, tail of the metric. What matters for this thing is tail of the metric, which controls ADM mass, ADM mass aspect. And it, first of all, it will be well-defined, and then moreover, it matched in this way. I don't know, I don't think there is a rigorous derivation in a full general framework. I would say that it's more like a correct picture that Strominger got. I don't know, maybe it is. As far as I know, that's a state of affairs. Maybe you can play this game of going from finite, I think, I wrote a paper about going from finite r, and some maybe in QED, but as far as I understand, in the full general relativity, there is no rigorous derivation. At the level of rigor, for example, as I will talk about Christa Duller-Kleinermann theorem and results which are pretty rigorous. But it seems to be completely correct picture, which actually always works and lead to correct predictions, and all the new conservation law come from realizations that this limit exists and then you have to match. So let's, this would be an important, this is a very important point. And here in this model, again, you just can compute it and verify that it's correct. Yeah, yeah, yeah, yeah, you will not see any memory. Yes, you will not see any memory, yes. That's a, so this is basically making sense of this story in high dimensions, namely how do you connect to asymptotic symmetries, et cetera, is an open problem, it's not done. But it should be all the same things, because the SOF theorem exists. So one way this way, one way this, for example, this connections work is that you find the Weinberg SOF theorem. You see that Weinberg SOF theorem exists in all dimensions, completely universal. So you know just physically that there should be memory in all dimensions. So you go to the GR literature and you see where these things go wrong and say, you see that it's subleading orders, things become subtle, but usually then you figure out how to proceed to make things work. So remember, so we found this formula, the metric here that we found was decayed as one over r. Now in higher dimensions, you will find that radiation, if you have a gravity wave, it's decayed like one over r to d minus one, but this h here, which will depend as a function of u. If you computed integral, it will be zero. Whereas if you want to see something on zero, you have to go to this order in one over r. That's the statement. Okay, so this is the end of the toy model. Here everything is explicit, but you see many of the things. And of course there will be huge non-trivial steps of this toy model and all the asymptotics and matchings. They're supposed to work in completely general and linear asymptotical flat Minkowski space. Okay, let me introduce you to the asymptotically flat Minkowski spaces and let me raise this part because I feel that in the center everybody sees it better. Okay, of course one, if you formulate the problem that we have asymptotically flat Minkowski space, there are many subtle questions about what do we exactly mean that things is asymptotically flat and what are the fall-offs on the metric which you usually impose by hand so that you capture the correct physics. So let me first write again the metric of Minkowski space. So now I will be focusing close to, we're talking about Scribe plus and space time close to Scribe plus. So now if we will be talking about the most generic space time, of course the metric can be very different from the Minkowski space and here I introduce just coordinates on a sphere which are convenient. So Z is related to usual angle like that. The gamma is a simple fact. Okay, great. Now if we attack the full non-linear problem, of course the space time can be very different from Minkowski space but the idea of asymptotically flat space time is very easy that when you're going far away the space looks asymptotically flat and look to leading order like that, plus small corrections which become small and smaller as you take distance to be large. The way to make it a bit more precise is first let me introduce again it's, I introduce it, I don't know if it will survive next years of development but until now it was a useful gauge. So if you have a space time at any point or you can choose the coordinates of this type plus, so this is just motivated by metric above but it has nothing to do with flat space yet. It's just a gauge which you can choose at any point and it's called a boundary gauge.  So as here fixed angle and fixed U, it's a null subspace. Now to make things more interesting we ask us the following question. Okay, this is just a gauge, it's always true. So what do we call asymptotically flat space time? Well, what we have to do is we have to figure what happens when R goes to infinity. What happens to the metric? And what happens to the leading order is easy to guess. It's just you get the same formula in Kowski space. So you get DS Kowski, let me write it. But now the question what happens next? And in general to figure out correct follow-ups, well, I haven't tried, but the lore is that it's a state of art because you have to basically figure out what are the correct follow-ups which allow for non-trivial physics but also exclude seek physics like infinite energy excitations, et cetera. And in the context of say four-dimensional asymptotically flat space times, this follow-ups work out correctly in the sixties by Bondi and Saks and friends. And let me write the answer. So now here, this is just a gauge, but here's the physical insight already enters because now I'm taking the R to infinity limit and I think of R as approaching now infinity and I'm saying to you, what is the behavior of fields in this limits? And here are how the people talk about them. So first, there is a correction of this type and B over RGU square. This is called mass aspect related to a sense to mass of a space time that you will see in a second. So at this line, it will be a little bit that you, if you want to read the papers you just have to accustomed yourself with this. This ingredients, that's the objects that people discuss when they talk about asymptotically flat space time. Then there is this CZZ tensor and this will be related to radiation. So CZZ is related to radiation. It doesn't have its name, but its derivative has a name. So NZZ, which is equal to derivative with respect to U of CZZ. That has its own name and it's called news tensor. Okay, so we have this. Then there is the term of this type. And now we will discuss one more piece, which is one more subletting in R, which has this form, probably the longest formula. Last complex conjugate. Okay, so that's the expansion of the metric at large R. And here is the main player, so it's mass aspect. It's a news tensor or CZZ. And this thing here is called angular momentum aspect. Yes, please. The bracket, the bracket for CZ, ah, close here. There is no bracket, sorry. Oh, there is a bracket, yes, yes, yes, yes. It's here and it close here, yeah. So it just refers to CZ that you have to take complex conjugate of CZZ, yeah. Thanks. Okay, so sorry, this is a derivative with respect to U. And important thing is that because it's an expansion at large R, all these fields, they adjust the function of all these fields. Let me write them phi, a function of U, Z and Z bar. So they only depends on the point on the sphere and this time. Okay, very good, so, yeah, very, yes, thank you. So now we have, we have, this is a sphere. So we're playing with the metric on the sphere. So these calligraphic Ds, they refer to covariant derivative on a two-sphere. What is this metric? Now we do the following thing. So let's now write the equations of motion. Or, okay, let me maybe do another thing. So far I haven't used the equation, Einstein equations, I haven't wrote. Now let me, let me write, yeah, let me write equations of motion so that we get a bit of an intuition about what's going on. Just to understand a little bit, to have some physical intuition about what are these objects, what do they mean, it's, let us consider, for example, these equations of motion, Einstein tensor, some matter, UU component, and we expand it at large r, and we get the following equation, UU of mb is equal to one quarter, of plus t2, z bar, and z bar, z bar. This one? Yeah, notice that the sphere, sphere has r square in front of it, in the Minkowski space. And here, this is the equation, and here the stress tensor tUU is defined as a, is equal to one, four, nz, z, nz, z. Plus the limit of the matter stress tensor. Okay, what does it mean? Well, tUU, you can think of tUU as a flux of radiation through null infinity. It has two pieces, if you have some massless particles, you have a flux of massless particles, which is equal to this. And nz, z square is a flux due to gravity waves. So this is a, this is a gravity waves. That's why this new, this new tensor is related to gravity wave, and it has its own name. Now you can, there is a famous, famous equation, which is, if you integrate this formula on the sphere, let's integrate it over the sphere. We get dU integral, d2z, mz, z bar, mass aspect. And this is just total divergence. It integrates to zero. And you get the formula that this is, and notice that tUU, if the energy, so this is the energy of the matter, which is positive. And this is a square of, also, it's an energy of gravity waves, so tUU is positive definite. We get that the change of the integral of mb is negative. Along the u. So it's monotonic, along scry. And this formula called Bondi-Mass loss formula. If you wish, the picture is that you have a space time with some mass, which is adm mass. The integral of Bondi-Mass aspect here at minus infinity is equal to adm mass. And as soon as you evolve forward in the future, your space time loses its energy, because it radiates it away. And the change of your mass is negative definite, because radiation carries energy away. That's a picture. So you wish, so mass aspect is a density of this integral. It is not positive definite anymore. And it has this energy flux part. And in the discussions of soft theorems, et cetera, this part is called hard part, because you can really measure it. And this piece called usually soft part. Because it integrates to zero, and it will be related to the subtle memory-like effects, which we discussed in the lecture. Now that's very, very simple. And now let's get the first, say, non-trivial conditions or set of conservation laws. And by noticing the following. Yeah, so it's an excellent question. If you write Einstein equations, we will find that there are relations between those. And so NZZ is completely unrestricted. You can take it whatever you like. And then for, there are extra data, which is integration constants. And there are integration constants for mass aspects. There is an integration constant for CZZ. And there is an integration constant for angular momentum aspect. So I will come to that. And there is a similar equation for, there is a similar equation for DU and Z. Let me write it. So that, again, you can do it yourself if you plug this ansatz and Einstein equations. You can check this formulas. There are also some leading terms, which are important. This is sometimes confusing in the papers because in the papers it's written this plus dot dot dot. But actually to get things right, you have to write some little bit of dot dot dots to add these components. Sorry, okay, so let me finish this. It's a question, again, similar to the one we wrote before. TUZ, it's, again, the same thing. It's related to angular momentum flux. You can show that TUZ measures the flux of angular momentum. Again, you can write it. There is, again, the soft part. There is also derivative of MB, but importantly, okay, you have this evolution equation for NZ. So what is the data after you plug all these equations? What is the data that specifies the solution? Well, let me write it. It's, you take N, NZZ as a function of U, Z and Z bar. And you take integration constants for, say if you wish, CZZ at I plus minus, MB at I plus minus, and Z at I plus minus. So these are first order equations. We have three first order equations. This one, this one, and this one. They're all specified in terms of NZZ, but they have integration constants. So these are these three integration constants, and this is a new tensor which specifies the radiation. That's a phase space. If you go to higher orders, I think it's an open problem, again, as far as I know in relativity to figure out if it's all the data, if everything is subleading terms related to that, or there are some new tensors. I think it's, maybe it's believed that it's all you need. If you go to higher orders in R. Now, here comes, by the way, I'm leading you with not the usual path. The usual path is that we have a symmetries, and then we derive the conservation laws. But in this, in this subject, it happens that it's easier actually to first find the charges in conservation laws and then figure out what the symmetries are. And that's what we will, we are one step away from this infinite number of new conservation equations. Yep. I wouldn't say so. So this is some, this is some data, this function in a sphere. It's not a number, actually. It's not a number, yes, sorry. This is a, because we are on the boundary, it's not a function of you, but it's a function of a sphere. So it has these three functions. Oh, it's crime minus one. Well, that's, I think that's the current picture. I don't know if it's not a theorem as far as I know. Yeah, it's a boundary, and then you integrate it with the news. So, well, it's actually far from my zero, because this, but yeah. On a picture, yeah, exactly. So you specify the three integration constants, and then you integrate along with the NZZ and the constraint equations. Okay, now we will do the step, the glorious step of getting infinite number of new conservation laws. So, and this step is as we, as again, I tried to explain a little bit in this toy model. Now you can ask, okay, we have our Penrose diagram. We identified the fields. The NZZ is a radiation. What happens, what are the asymptotic properties of the fields as they approach boundaries of scry? If I ask you if I give you some system, nonlinear equations with some matter, it's a non-trivial question. And, well, in particular in Strominger's paper, it seems to re-occurring result which pops out in this discussion about by Kristadul and Kleinermann. It's, I know nothing about it, but so this is some rigorous theorem about nonlinear stability of Minkowski space. The idea is that if you take some Kashi data which is finitely but small, close to vacuum, it all disperses to now infinity and you don't form a black hole. But also they figure out, from that, the fall-offs of these fields. In particular, you can ask, how do we know that if I take the limit of these fields on a scry, when u goes to zero, it is at limits exists. Maybe it blows up, maybe these fields blow up as we take u to infinity. In a paper by Strominger, he referred to this paper, this result from this theorem where they show that, say, a new tensor, it falls fast enough that you can integrate it. And this limits exist. As far as I know, this is only, say, you can refer to this Kristadul and Kleinermann only to show that this guy exists, this CZ guy. Even this thing about mass aspect is just a conjecture again because you see that it works. You assume that it exists, then you do some trick and you get some relations which happen to be correct when you check them. So it suggests that this is a correct picture. Moreover, then another stretch is, okay, Kristadul and Kleinermann is for spacetime without black holes, but again, this picture seems to be correct even in the presence of black holes. So maybe this Kristadul and Kleinermann, I don't know what's its role at the end. Maybe that's just a correct thing, correct way to think about scattering and it's extremely hard to prove it with some mathematical rigor. Anyhow, so, with a small digression about this famous result, we get this data. Moreover, we believe that this limits exist and now the idea is that, well, if we have a scattering problem, we believe that say there are some symmetries here, there are some symmetries there, there are generators of symmetries, there should be some match along this point I note. There should be some match of the fields and the idea that the correct matching is this antipodal matching, let's cry. As we write before, now we write the following things. Mass aspect, Z bar at i plus minus is equal to i minus plus where important points at this coordinates which I choose on the sphere are antipodal. So if you take point Z here, if you take point on the sphere in the north pole on this part of the equation, the same point Z and Z bar in this coordinate on scri minus corresponds to the south pole. So you identify fields with a flip. Is that clear? What are we imposing? We are matching this integration constant here and here with a flip, which is very non-intuitive. And you can ask, okay, how is it possible? We have a completely smooth date on spatial slides. How is it possible we have a flip? Well, it's possible that these points are really not close to each other. You should not think of them as close to each other. You have some smooth data, you take some limits and you get this picture. So as soon as you have this equation, we get an infinite number of new of conservation loss, as you will see now. And the second equation that we will write is related to the same type of identity for all other three constants. So we have the same thing, we have for NZ, again with a flip and the same hip for CZZ. There are some minus signs involved, but I choose a convention such that we get the flipping. Let's see what are the consequences of this identification. To get to it, it's very simple. Let me introduce some hints. The conservation charge. Two set of conservation charges.  And here we have mass aspect ZZ bar at I plus minus. And this conservation charges will be super translation conservation charges. Super translation. I haven't explained why so far, just we are following the road of charges. And the second set is the same thing but with angular momentum aspect. So you take some vector field and you integrate gamma ZZ bar, angular momentum aspect. So this is another set of charges. Why do I call them conservation charges? Well, let's integrate this equation with some function F and with some vector field Y. Now notice that we can use integration by parts and write, simply, we can write, for example, here, we can rewrite it as an integral over scry plus of dU dU mB, the minus sign. So here was a minus mB i minus minus. What I did here is simply integrated by parts, if you wish. I rewrite, this is the integral of total derivative. It's equal to the difference of its boundary values. This is a one boundary value and the second boundary value I just subtract. Start with these charges and then I rewrote the total derivative. Okay, now we are getting, and now for this total derivative we can use Einstein equations. Exactly this. And for this term, imagine that we start, we consider space time where it starts in a vacuum. So mB is zero and it ends up in a vacuum where mB is zero. Consider space time like that. This term is then zero. Now we do the same thing on the left-hand side and we use again equations of motion for mB. How much time do I have? This is, if you do this for these equations and for these equations, this is what is called this infinite number of conservations law for super translations, this is this. And this is called super rotations. What is the meaning of this conservation laws? Well, let me first discuss super translations. So we're doing this procedure. We get the following identity. We get that the integral of this right-hand side, no, it's absolutely arbitrary. Yes. We get that the integral of this thing on the square plus is equal to the same integral with, again, it's a typically matched point on the sphere on the square minus. So this is a crucial point. Now what is the meaning of this thing? Let me explain. Let me write first the same thing here. So this is the flux of energy in y minus and y plus. If you choose f, if you choose f to be constant, this is just the conservation of total energy. This term integrates to zero and then we get that the total flux of energy through a square minus is equal to total energy flux of square plus, yeah? Oh, thank you. Yes, I'm sorry. Absolutely crucial. Yes, it's... Yes, there is dv. So now this fields, the functions of u and z. And if you take f to be its lower harmonics on the sphere, say, if you take a constant, it's just the conservation of total energy and total momentum. This piece drops out and you get that total energy is equal to total momentum. Now the idea is that what we have arrived is that it's a new set of identities which express some conservation, but for any function of f. Sometimes this thing is called... For example, let me choose f to be a delta function on a sphere. Then sometimes this is called energy conservation at every angle. This might be confusing because how can energy be conserved at every angle, you would say? Consider scattering of two particles like that, which end up being like that, and measure the energy flux somewhere here or somewhere here. Clearly energy flux is not conserved. So this part is different from the point on the sphere. However, the point is that this integral of N, notice that for this part we can do this integral over U and it will become just Czz. So it will become the soft mode because remember that we can plug for Nzz du Czz and then we can just do this integral and we will get this soft mode. So the idea is that the change in the energy flux at every angle in the antipodal image spheres is exactly compensated with this change in the columnic field which you can measure with a memory. Find useful to think about it is that you say that energy... energy flux is not conserved at every angle but it's remembered. If you take a flux plus memory in the past, it's equal to flux plus memory in the future along every angle. So that's what the super translation conservation is about. Any questions? So far you should be... Here's a charger. You see it's co-dimensioned too in the quantum field theory the question is in the quantum field theory the charge is defined in co-dimension 1 here we have the sphere whereas the charge is given by the value of the field on the sphere or the integral on the sphere which is co-dimension 2 but this is because it comes from gauge theory. The simplest example of this type which you can have in mind is consider a particle which is freely propagating through flat space. Minus infinity to plus infinity. In this case this change in the memory will be trivial as it will be zero and then you see that the flux of energy on untypedally matched points on the sphere because if you start with some point if you start with the south pole and you then propagate forward you will end up in the north pole so then this becomes trivial. So that's... consider your favorite example and see that it works. Great that I confused everybody. Please ask me questions if you... Yeah, so if you... remember we... we discussed in the first lecture this model where it was H so this... to connect to the previous lecture just think of Czz as being H and then you integrate Nzz you get delta Czz which is delta H so it's a memory and this is the centipidal matching that we discussed for H now you can write exactly the same... exactly the same identity for this second set of charges using this equation and again making... you will get something which looks like relation between fluxes of angular momentum this type of expression it has hard part which is this which is really if you put a colorimeter and you measure the flux you will measure this and it has a soft part which is something that will be measured with some type of residual deformation in your detector for example this... for this guy you can measure it with some clock desynchronization but there are many other ways anyhow so this... the philosophy here is always that this new conservation laws they generalize the existing ones like energy conservation momentum conservation by including this soft piece now... that's a picture notice that I haven't...  I shouldn't have raised that the idea would be now that if you... if we call them charges so what kind of symmetries they generate that's the next question I would like to ask so we identify infinite set of quantities which can serve we can use them to constrain the data given if you know something if you know something on SCRI- you know something on SCRI+, and the next step which I was going to explain is, ok, miraculously in hindsight identify the charges what are the symmetries that they correspond to and we will find that these are indeed the charges and they do indeed generate the symmetric symmetries that's... that's the idea and moreover if you assume well... if you assume that these charges commute with S-metrics if you imagine now some quantum theory scattering and you assume that they commute again maybe for for super translation you can try to relate to some ADM Hamiltonian and... argue for this but for super rotation basically I think this is an assumption again that these things commute so if you assume that if you consider this as the charges and you assume that they commute and then you sandwich these identities into some in and out between some in and out states you will recover soft theorems that's a connection to soft theorems and this way you get these charges which are conserved they have a flux of energy which is familiar they have this memory part if you sandwich them between the S-metrics they generate soft theorems and this is a notice that's completely full in on linear analysis of Minkowski space we don't... so we jumped from the linear simple problem to full in on linear problem there is no approximation here if there are no questions I would I would like to... in a five or... ah no if I just I lost the track of time ah we started at 2.30 so yeah I should... I will finish in a minute ok so now in principle I would have to explain I would like to explain two more things and I will explain them then partially in the next lecture is that one thing is that this a bit unusual unusual thing from charges to symmetries from charges to asymptotic symmetries so we will find that we introduce the notion of asymptotic symmetries and then try to find the charges that generate them we will find that this are they this are those and then ah from another second piece is that from these charges to familiar soft theorems because you if you think about scattering amplitudes you are used to think in momentum space here everything in coordinate space and so to go from this charges in coordinate space to usual soft theorems there is this sort of LSE procedure Lehmann-Symanchik Zimmermann in coordinate space so this is this are the things I will explain next time thank you


Hi Ian, good to see you. How are you David? We talked way back in the early days, so after Linnar had first started a bad enterprise and how we might tackle that. I don't think you had grey hair in those days. I've got more of grey hair anyway. After that leg was formed and all these two or three years have gone by now and this morning in the keynote we had AMD with real hardware, real software, all upstream, done properly. Exciting isn't it? Yeah, exciting. So where do we go next with this thing? Wow. So I think there's a few things, right? If you think about what Suresh said this morning, he was talking about standards, right? And I think one of the exciting things is to see these sorts of products coming out with a standard platform. He mentioned Trustzone as well and SPSA compliance. And I think that's really going to be a platform he talked earlier about the real need now to actually go and put more software onto these things, right? Yeah, we've got a base and the benefit of SPSA is people can get software written once as a kernel or whatever and it's all going to boot in a consistent way. Right. And you're not wasting effort everybody doing their own thing. Right. And standards drive the whole enterprise market. Yep. And I think we need to see standards in other markets as well because I think everybody doing everything slightly differently, mobile, particularly in embedded is going to be pretty inefficient. So I think we need to drive standards in all areas. I agree. And I think one of the things that you see with the networking areas, I think we've realized that if you look at SPSA, it was a very low level set of standards, right? Yeah. Booting of a device in a standard way, devices on PCIe enumerate themselves in a standard way. Pretty standard stuff. If you look at what we're doing with ODP now, we're trying to bring that up at a standards level so sort of middleware and application software can be written in one way and it will take advantage of all the goodness. The programmer writes it once, but it will take advantage of the goodness on a Cavium part or an NVIDIA part or an AMD part. Right. Really away from the programmer. And I think one of the things we've got to look at is where's the right level of those sorts of standardization, not just down at low level firmware, but what are the right things further up the stack? Yeah, I agree. There's a bunch of key areas where with the right standards, not too many, not too few, but how they link together will really level the playing field and allow the ARM community to really compete in those places. Yeah. I mean you look at power management, one of the great things about the ARM architecture is people's vision of how they can conserve energy, right? Right.  That's much about software frameworks, which are also a standard.  I'm a dumb hardware guy, so I just lump them all into the same thing.  So the other thing that's been happening in Lunaro, perhaps you might want to comment on, is the members are putting more engineers in. So they're taking their teams that are outside of Lunaro, putting them outside the firewall and really working on the things that they want to do. We call them lead projects. ARM's been doing amazing things, putting teams in various parts. You're very kind. I mean, we're... Thank you, yeah. Yeah, well, number one, we're committed to Lunaro. I think it was something like 50 ARM people here at Lunaro. I think it's about 70. Oh. There's a huge number. 20 other people snuck in.  You know, you look at what we are. If we are to really grow an ecosystem around our own products, whether that's for servers or networking or mobile platforms or other new things that, you know, other new areas that we're looking at to do standard work, we have to pull those resources, right? And so for ARM, we have to go off and invest in that group. We're committed to doing that. And what's coming out at the other end is you're seeing, first-class citizen releases, you know, and kernels coming out optimized for the ARM architecture. And the way we're going to continue to do that across all of these markets is by putting more into that central area. That gets a, you know, we want downstream kernels to be taking full advantage of technology like Big Little, other new things that will bring out in the architecture as we come out going forward. We do that through Lunaro. That goes upstream, and then all of these other distributions take full advantage of it. Everybody benefits. So it's been five years. I can't believe Lunaro's been around five years. So when you were there at the start, I was. You were always enthusiastic. So hopefully we can do this interview again in five years time. More grey hair. Hopefully similar way. Hopefully the grey hair will be fine. I'll be here in the next five. Thanks for all that cheer. Thank you, David.