Okay, so let's change the topic a little bit. So my name is Lily. I'm a postdoc in condensed matter group in ICTP and I work, I'm working with Sandra Scalow. Today I'm going to show you the face diagram of Aaron up to the earth in the cold conditions. Before I go to the neural network potential I developed for Aaron, let's let me just give you a very brief introduction to the earth's interiors and to explain to you why we need to care about Aaron. So every year, there's a lot of earthquakes happening all over the world. On the one hand, it caused harm to human life and human properties. On the other hand, it brings invaluable information about the earth interior, and from this seismic observations, we could get the seismic velocities as a function of depth. And based on the discontinuities in this distribution, we could divide the earth into three layers across the mantle and earth core. As for the earth core, we could further divide into the outer core and the inner core. For the earth outer core, its shear velocity is zero indicating it actually in this liquid phase. For earth inner core, its shear velocity is not zero, suggesting that it's actually in a solid phase. However, geophysical studies won't tell us what is the major conversations in earth interior. For this, we have to use geochemical studies. So, now we know that the major elements in the earth's interior, in the earth's inner core, which is made of iron, nickel, silicon, oxygen, and sulfur. However, neither of these studies could tell us what is the most thermodynamically favorable phase for Aaron. There are a lot of candidates such as BCC phase, the AGCP phase, and FCC phase. So for this, we use density functional theory based method, because clearly, it's very hard to perform diamond adversarial experiments combined with x-ray diffraction pattern at earth inner core conditions. Now, those of this experiment data are not very consistent with each other. The last two decades has seen a great advancement in what we call the computational mineral physics, which is a subject that focuses on the physical properties for different minerals that is relevant with the earth's interior. This is exemplified by these two studies that published in the early 2000s. These studies are actually about the melting curve of iron after the earth core inner core conditions, and these studies actually use only 200 atoms. 200 atoms are actually enough to yield a very accurate estimation for the melting temperature. So why we need to use machine learning potential. This study is really inspired by our previous work done by Benosca. In their study, they perform ab initium molecule dynamic simulations in the MPD ensemble at 360 GPA and 7000 Kelvin. So they found it out that if they perform simulations with the less than 500 items, okay, you can see that the PCC phase is no longer stable. It will automatically switch into the ACP phase. However, if you perform simulations with more than 1000 items, okay, PCC phase is now stable. So clearly, the stability of PCC phase will depends on the how many items that are used in your simulations. So you might wonder that whether the simulation results are converged with respect to the number of atoms they use in simulations. So for this we couldn't use ab initium molecule dynamic simulation animal because it's very expensive. So for this we use machine learning potentials. So we choose, we choose this deep and deep kid package to develop our machine learning potentials. I just want to mention one point, what makes the different difference between this kid and other packages. This is because of the structure descriptor, you can see in the figure B. So if you want to know more details you can read the original paper by Lin Feng Zhang and the latest work, which is overall review, which is given by this paper. So in order to generate neural network potential, the fourth thing is how do we get this training data set. So in this study, we follow the idea, which is called the optimal potential method. In this method, starting with the several configurations, we use a deep MD kit to train for neural network potentials with these four neural network potentials share the same neural network parameters other with different random states. We use it for neural network potentials to run MD simulations. Based on this, this arrow indicator, which is actually the maximum for deviations given by this for new one new one network potentials, we choose several configurations. Once these configurations were then labeled with the DFT simulations, the labor the DFT labor structures were then incorporate to retrain the full neural network potentials, and we repeated this whole process until the labor structures for for below around 10% In this study, we would like to cover a different iron face includes including PCC, it is a BFCC and a legal phase. So considering the extreme conditions, we also want to cover in the pressure and temperature conditions that is starting from 4000 Kelvin and 75 GPA to around 7000 Kelvin and the full 450 GPA. So one, one point that it needs to take a very special kind of attention is that because I work, work on this metallic system at high temperature, we really consider is a simple electric excitations. Okay, so that means we now use the moment extension of density function theory, which is also called a final temperature density fun theory. But now, the extended collision functional include the entropy difference between the non interacting electrons and the interacting electrons, electrons. After the training data set is generated. We retrain only one neural network potential, and then the final training root mean squared error for pressure is around 0.5 GPA, and for energy is about five and people Adam for force is about 0.2 seven you a point strong. So if we characterize the performance of the DP model, we use the train the neural network potentials to run dissimulations for different face, and for at a different conditions. So we select several configurations, what then would they build with the DFT simulations by comparing the prediction given by the DP model and the DFT simulations, we could calculate the test error. So for the energy is tested error for if the system is less than 200 items, it is around the five and even Adam and for force about 0.3 and even Armstrong for pressure is about 0.6 GPA. We also consider the final size effect. For this we run a bigger simulation cell for, for example, for it to be our right now you use a 216 items. Okay, so, but the performance is still consistent with the smaller cell and with the, with the, the, the, the error in a training data set. So the overall consistency suggesting that there's no underfeeding or over floating problems in my deep, deep model. In the figure on the right, I should actually show this normalized force error because somebody is very interesting in this figure. So it's actually measure the, the, the first difference between the DP model and the DFT simulations divide by this absolute value for the force. So for all the conditions and for all the face, the relative force error is below 10%. To determine the face diagram at high pressure and temperature, we not only need to know the pressure, the force and the internal energy is very accurate. We will also need to know the friends the difference between the DP model and the DFT, DFT simulations. For this, we run molecular dynamic simulations. This is only example, a given example for the ACP iron. We run, I'm dissimulations at around the seven gram per centimeter cube and a thousand Kelvin with only 100 items. Then we also select different civil say ratio. Then we select several configurations, which was labeled with DFD simulations. So in a, in a figure on the top, I show the energy difference between the DFT model and the DP model. And we can clearly see that the energy difference is a force within around five MVV per atom. Let's think about the free energy perturbation theory for free energy perturbation theory. In the first order, the friend difference is actually equals to the internal end difference. So from the table from figure on the top that shows actually our friend is very close to the DFT to the DFT potentials. We can also incorporate the second order corrections that is related with the standard vision about this internal energy difference. So by plugging all the numbers into this formula, we derived that the friend, the deep, the friendly accuracy is below one MVV pattern. So this is, I mean, it's very accurate. We also compare the relative force error, which is very consistent between the DFT potentials and the DP model. In the end, the last property is very interesting. We compare the difference of Sigma 33 minus Sigma 11 between the DP model and different simulations. So this, this, this difference is very, is very important because for a nice social bigger solid face, you would like to hear the very accurate cell parameters. Otherwise, we will do some dimensions for the solid face. You will have extra elastic energy in it.  So this slide is actually my personal interest because I would like to know whether some like discrims in the leadership is caused by simulations with different simulation package or different pseudo potentials, or different extended collision functionals. So for this I reused the previous snapshots and redo DFT simulations. Okay. But for different simulation package, they have different zero energy. So now the absolute energy doesn't make any sense. So what we can measure is that the Internet difference between the first configurations and the configurations in the in the following. So let's say not from the figure on the top, you can see that for different simulation package and the external collection functional, or different showed the potentials, they give a very similar, or exactly the same energy difference that actually indicates that if we will do simulations with the in the top, you will get the exact very similar the face face diagram for our comparing to the simulation given by Conan special. So if you find some great discrims between different studies that must not be caused by simulation itself, it must cost by something else. So we also compare the relative force. And the last point is that we compare the Sigma, the difference of Sigma 33 minus, and the Sigma 11. And also again, this quantity is very is very consistent between different different potentials. Okay, so that means if you run simulation with advanced, you will get exactly a C was a C was a ratio, compared to the simulation by vast. In the ratio in the literature that for this quantity, the C was a ratio is scattered. Before we apply our potentials to a very big system, we would like to know whether we can do that. So we need to again test the final size effect. Okay, for this we run a very big simulation cell with more than 400 items. Okay, but here we don't do for all the faces at the, at the issue conditions, we only select several conditions to do a test. Again, the performance is very consistent consistent with the smaller cell, and based off free energy perturbation theory, we know that the accuracy of our free energy is less than three and maybe Adam. So that's very accurate. We also do a little bit comparison between the previous and potentials, because I mean, the embedded Adam method has been frequently used in a literature to study the metallic system. In this study we use a parameter parameters from this binosical 2002 2001 paper. So, for the, for the relative energy era, which measures the energy difference divide by the fluctuation of the energy for the em potential is, is a relative energy error is more than 10%. And for the relative first era, the em potential gives about more than 30%. So that is a little bit surprising because in the past, people think that the em potential is very accurate. And actually it's not that accurate. So I don't think I have enough time so I just give you a few, few cases, and to explain to you that actually we can use a DP model to solve some longstanding problems in earth science. So the first key, the first example I want to show is that the sea was a hit ratio for it to keep an iron at 360 GPA. For it to keep an iron is called audition number is a 12, however, for this 12 neighboring items, it distributed evenly. That means the atomic distance that is represented by this blue era is different compared to the atomic distance that is represented by this red arrows. That actually has some impact on the sound wave propagations. So if the sound probably in this way, they probably has a different sound velocities, if if the sound propagate in this way. So that's a big impact for how do we interpret the seismic observations. To calculate the sea was a ratio we could use a different method, for example, we could run nvt simulations at a fixed volume that will adjust the sea was a ratio to one to find the one point that the difference between the sigma three and the sigma one one is zero. And then we use thermodynamic integration method in this method, we vary the sea was a ratio, then then we use thermodynamic integration to calculate the hammers of frenzy, we found one point that is how much the frenzy is, is at its lowest point. Our results are consistent with the previous some of them integration method, but has a very large discrepancy compared to this method. But so we couldn't figure out what actually causes this, this discrepancy, but what do we can see that our simulation are converged comparing with the experiments, or can say that our sea was a ratio is actually larger than the experimental work. However, for, for this such this very difficult experiments, they only sometimes you only have around two diffraction peaks, I mean based on two diffraction peaks, you have a two premise you have a two diffraction peaks, we, it's very hard to evaluate the error in this sea was a sea was a ratio. In the end, we calculated the is lasting constants of the C11 and C33 as function C was a sea was a ratio, because in the past people will think that if the sea was a sea was a was a ratio is close to the ideal value of around 1.63 C C 11 and C33 will be equal. But from our simulations, we found that it's not equal that access in suggests that for elastic constants isn't it's not only related with this shorter range correlations is also related with a long range structure correlation. Based on our elastic constant calculations at a 360 GPA up to 7000 Kelvin, and it's the results from our study agrees very, very well with previous studies. And based on this elastic constant calculations, we could estimate. Okay, the sound of velocities at earth in the core conditions. So our calculation suggesting that for the for each CBR is a shear velocity is actually 20% larger than a real observations. So that's actually the first order of times problems, how do we explain the very low shear velocities at the inner core conditions. So we are still working on that to find the plausible possible cause for that. So this probably is very is more related with the reality properties for our own. So at a high temperature high pressure, especially at a, at the earth this very long age. So the, the, the solid is no longer elastic, it has some reality properties. So from MD simulations for each to be our own with the 447 items. We also put a one weakness in it. Then we calculated the, the mean square displacement based on the mean square displacement we could add, we could estimate this effective self diffusivity. But in order to calculate the real diffusivity we need to know the incredible because in concentrations for this, we use thermodynamic integrations. So this is particularly the French difference between the perfect crystal and the crystal with the one we can see, and our results are shown in the insect. So it shows that comparing with the previous work, our, our, our value actually is a 1.5 EV lower than previous estimations and this discrepancy is clear by by the hominicity that is not included in the previous study. So this, all this for the, for vegan free and vegan form of formation free energy, and this effective diffusivity we could estimate the self diffusivity for a real system. Based on this we could also get calculated the viscosity that's not shown here. So for the take home message, the optimum potential method is very efficient in generating the training data set. So we have was set up a very excellent RN potentials. So well constrained the sea was a ratio for the first time also for the first time, the last constant for each is to be our own. The self diffusivity has also been determined. So this is also ongoing, ongoing process in order to determine the whole face diagram that covers the from, covers from the whole in interior conditions. So thank you for your attention. Any questions. Thank you for the nice talk. It was very one for work. So, in the beginning you mentioned that I will meet you MD is limited to hundreds of atoms. So but it is says dependent, you have to go to thousands of items to decide to calculate the property that he want. But in your model you, you didn't go to thousands of items to validate it right. Yes, yes, although I didn't go to 1000 items, but I did a test at 500 items, it doesn't show any finances effect. So I think the potential is converted. So probably this, this phenomenon is not related with a long range of potentials is more related with the collective collective motion of items. So that is different, different things. Yeah, I have a question related to this I mean I know this is not your work but it's the interpretation of this data seems a little bit dubious to me because if this conversion from BCC to FCC or what it is is a rare event. Right this is a single observation for the 432 atom cell. And then you have the longer trajectory on top that is twice as long maybe you don't observe the event but is that really proof that this was the size effect at all I mean this could just be that if you run the top one for longer that at some point it switches right. So that's also the point we would like to try so yeah. Because for ab initium oligodynamic is this is the largest cell you can you can do. I think for this simulation is you will be wrong around one year. Okay, thank you again.


hey jam to another welcome back to another therapy Thursday it was a good session I feel like I needed more time because it's been such a heavy and long and overwhelming week every time I get to a point in therapy where I feel like you got this you doing your thing you healing you moving on you know you're good spirits and then life happens and I get back into a space where I realize that you got more to dig up you got more to face you got more to analyze and process and release listen although I went to therapy for one specific thing I have to remember that I am dealing with pretty much 30 years of unprocessed emotions and realities you know and when you think about it it all kind of just boils back down to when you think about it it it definitely goes way back to like your childhood and we all have an inner child that needs healing so this work is definitely continuous I don't know how long I'm gonna be in therapy but I don't think I'll be stopping anytime soon because I gotta I said that work to do you know I had a rough week mentally like my mentally I am overwhelmed I'm exhausted and a lot is going on in my head I've been very much in my head all week so I haven't been as productive as I wanted to or needed to be so we were kind of just going through what is causing that for me right now even last week I had yeah last week my son had a meltdown and I'm not gonna go into all the details but he I was you know I was getting them ready for bed and you know he was upset about something he was crying and screaming and he was just saying a lot of mean things and you know I the only would react because that triggers me stuff like that triggers me but in I've learned to not react and instead talk him through it and try to help him identify his feelings and help him understand why he's feeling like how he's feeling in that moment yeah at one point but he blurted out my baba died already I only have you and in that moment I broke down like I started crying and I had to just I had to step away from the situation so I asked my mother to finish getting them ready and I went outside and I cried for like 20 30 minutes because like although I know that I'm their only parent now like with him saying that in that in such a emotional way and such a hurt like you could I could hear it or hurt in his voice I could see the hurt on his face and he said it was so much passion that like it hit me that like I am all you have you know like the one thing that I cannot do for you is bring your baba back I could never fix up for him I'm not gonna cry I could never fix stuff for him nobody could replace that not even my father like my father doesn't even replace the absence of his baba because my father doesn't do the things that his baba did for him or did with him and I can't even put that on nobody I can't I can't ask anybody to be that for him he misses baba you know like he if he can verbally say that listen my baba is dead but I don't think he fully completely understand what that means yet he's still trying to process that and I just after I calm down I came back inside and I he was laying down and he was still crying and I just rubbed his back and I had to just talk to him and explain to him like it's okay for you to miss your baba it's okay for you to be sad about missing your baba or be sad because your baba is in here and you know I told him like I get sad too I get sad sometimes I said but you can't take that out on mama like I am not it's not my fault that your baba is in here it's not your fault that your baba is in here you know and I'm sorry but I cannot I can't fix that for you I can't bring him back but because I am all you have you have to be kind to mama you have to be respectful you know we have to work together we have to stick together and you know like as I talked to him and told him like I do the best I can for you you know I make sure that you're healthy that you're safe that you have everything you need like I do the best that I can for you at one point he did say like oh you're gonna at one point he said like you're not my mama anymore whatever you know he was just burning out things so when I when I was talking to him to calm him down I asked him I said you don't want me to be your mama anymore he said yes I do and I said do you want to be around mama he said yes I do so like he I know he was burning out those things out of frustration and and and confusion and anger and whatever emotions he was feeling but I had to bring it back down to reality to him to read to make him understand that his words carry a lot like his words can hurt feelings his words can hear your words hold power so I said you cannot say those mean things to mama because I am all you have and you know I take care of you and you know I love you so he calmed down as I talked to him and explain everything to him anyways I say all of that to say this because I was having a heavy week and I was way more emotional than I've been in a very long time this week and a lot of stuff has been coming up for me and my therapist pointed out she was like do you think that that incident with my son last week him pointing out that I'm all he has kind of triggered something in you to feel like you have to do everything alone and I I thought about it I was like wow yeah because everything is my responsibility even with the support that I do get at the end of the day it is my responsibility if I don't ask it doesn't get done if I am not on top of things it doesn't get done if I don't if I don't initiate if I don't if I don't remember like any little mistake at the end of the day nobody else is there to pick up that slack because it is my responsibility if I need help I have to ask for that you know even last week when I was sick like I was so out of it so out of it but I still have to cook I saw how to braid the hair make sure they got ready for the week do laundry like I literally dragged myself to the day feeling like shit because at the end of the day it's my responsibility and if I don't ask nobody's gonna say hey I see that you're not feeling well go and get some rest I'll do this you know so I did ask I asked for help at the end of the day and thankfully I did get a little assistance but which I am so grateful for but my point is it is my responsibility and that gets overwhelming sometimes and that's what's been happening this week like everything is hitting me at once if I drop the ball it's not gonna get done and it's just weighing on my head the another thing that I explored in therapy today which part of this I know is because and if you understand how your chakras work and you also understand that women hold emotion and trauma in their womb and their hip area you'll understand what I'm about to say this week have been because I do yoga and Pilates pretty much every day but this week specifically I'm I'm consciously and intentionally focusing on my hips and opening my hips so I've been doing a lot of hip openers this week which I usually don't work on hip openers because it's such an uncomfortable thing for me but I I really do know that I hold a lot in my hips which is why I am being intentional about it now and I've been a lot like a lot of emotions just started coming up for me and a couple days ago I was talking to somebody and I realized that I don't vent to this person anymore and I didn't I didn't notice it there's more than one reason for all of that I'm not gonna get into details but I'm gonna get to the point so I was telling my my therapist about you know my relationship with this person and how I don't vent to them anymore and she pointed out that oh she asked me why do I think that is and I told I thought I thought about it because in the moment when I realized I don't vent to the person anymore I was the person said like you know I'm here you know you can vent for me vent to me and in my mind I'm saying like why would you make that assumption you know you can vent to this person you know this like it's a safe space it's okay but a voice in my head immediately said nah they don't think you're weak in that moment I got emotional and I started crying and like I was like what is going on why are you crying why do you feel like this what is happening why is all of this coming up I was so confused but I just sat there in that discomfort and thought about it and I realized that in my last relationship the more I vent to him the more he called me weak the more I express it the more I asked for help the more I wanted him to do things for me or with me he called me weak especially when we lived in Ghana like he compared me to the Ghanaian women and just said that I wasn't tough enough and that how I because I didn't want to live such a hard life and I didn't want to do certain things like I was just weak to him he called me weak so much that I shut down I stopped opening up to him of course I stopped asking him to do me do anything for me I just I completely shut that down and I started to do things on my own and did things so that he didn't so that I didn't have to hear him call me weak or see me as weak so anyways when that voice said nah they don't think you weak I immediately realized after think no after thinking about it I realized that like you have subconsciously shut yourself down because of this man and how he calls you weak and like I know I'm not weak but now I have to rewire my brain to understand that just because he saw you as weak doesn't mean another man is gonna see you as weak you know because a real man would know that he should be a safe space for you to vent and to unload your feelings and emotions and your needs on him and although I used to vent to this person my therapist pointed out that maybe the reason why I stopped is because the dynamic of our relationship changed and now you're putting up a wall because subconsciously protecting yourself because of what your ex did or what your ex said you know I don't know where I'm going with all of this I'm just working through stuff as things come up I'm working through it and now I am just going to work through that I'm going to make a conscious effort to open up more and feel safe in doing that you know and know that although I know I'm not weak in any capacity like I also need to know that whether or not someone else sees me that way it does not matter but specifically people close to me yeah I just it's I just kind of been going through it this week that's all I'm going to shift my focus because one thing about me is that I don't I don't thrive in multitasking like I work better by focusing on one thing at a time and because the people around me feel like I have to do all these things at once and be able to do everything and be a mother and be a business owner and work and take care of home and it's a lot it's a lot and I don't have another person there who can equally share that responsibility for me so when I have to ask for help and the response is oh you should be able to do it by yourself I shut down in shutting down I start thinking about all the things I have to do on my own and I get mentally overwhelmed and I become unproductive and I guess in short I kind of I've been feeling a little stuck this week and my therapist said stillness is productive too and in that stillness you'll be able to I can't remember the exact word she said but she pretty much said like in that stillness you'll be able to figure out what you need to focus on next and find direction so she said be still until spirit tells you to move again and listen that was a word okay be still until spirit tells you to move again because then when you move again you will have that motivation you will be productive and you will be focused and you'll be able to pour into whatever it is you're working on so I've been so hard on myself this week because I'm like I need to be productive I have a timeline I have things I have to get done if I don't do it it's not gonna get done but girl just be still just be still so I'm gonna refocus and try again next week anyways I did not mean for this video to be so long I kind of was all over the place with what I was talking about but that's because we were literally all over the place in therapy today because it was just so many different things that I had to pour out and then she like connected the dots to everything and at the end of the day it boiled down to me creating some mental ease so that I can refocus and give myself some grace so yeah anyways I hope this video turns out to be somewhat informative or helpful to somebody because I know when I'm editing this I'm gonna be like what are you talking about why are you all over the place there's no direction with this video but that's that is literally the direct reflection of what my week has been so I hope that if you've been thinking about going to therapy that this video is a reminder for you to start and to all my Melanita women protect your womb by any means necessary and to everybody watching protect your peace by any means necessary I wish you all love light and prosperity and you'll see me in my next video