 Hello everybody and welcome to this low physics webinar series. So welcome back. And this time we have Daniel Lopez Foliani. He is professor in the University of Buenos Aires, also Conecinette, and professor in the Pontifix University of Catolica de Argentina. Here in the past he did the PhD in the University of Tunoma de Madrid, and also he did some postdocs in Sheffield and in Norside. So the talk of this webinar is going to be very interesting because it's going to be about supersymmetry, and the title of this talk is going to be reinterpretation of the Higgs field, new quarks, and neutrino physics in supersymmetry. So Daniel, if you are ready you can start your webinar whenever you want. Okay, thank you very much. Hello to everybody. And let's go for the transparency, okay? Let's see this works. Okay, can you see the talk now? Yes, we can see the slides. Okay, then as you said the talk is based in reinterpretation of the Higgs fields, new quarks and neutrino physics in supersymmetry. This talk is based in a work in collaboration with Carlos Munoz, this is the archive number. And let's start with the situation in this day. There are a lot of people in this day saying that supersymmetry is already dead or more or less, but this is too much to say. But let's try to understand why we are in this situation with this pessimistic in the community and then which was the situation in the 20th century. Let's say at the end of the 20th century. We were completely sure that the neutrino was dead or more or less until 98 when the situation changed and we started to discover that neutrino was massive. Then a lot of Darmatter experiment were running at that time, especially direct detection of Darmatter and people were really very optimistic with this. The idea was that Darmatter will be discovered very soon. And also in experiment of colliders where the idea that things to missing energy that was the main point in the simple model of supersymmetry it will be easy to find supersymmetry. And it was the situation. The situation was a standard model with the spectrum of the standard model that this one is well known and it's the fermion of the standard model and there were no needs at all for right-handed neutrinos. As I said at the end of the century we realized that the neutrino was massive but the first approach was to say ok don't worry about this because in principle you can give much of the neutrinos without doing a finance and then you could continue working with the standard model as usual. Of course the standard model has this gauge group apart from the leptons and you need to add a hex boson that introduce in the model the hierarchy problem. But in principle everything was nice and working very well. For the MCC and the minimal substandard model things were really better because the minimal substandard model was correcting the hierarchy problem of the standard model. Since to her parity there was a Darmatter candidate in principle the neutrino was the candidate that people like most and a lot of the experiment of direct detection of the Darmatter were there and people were expecting to detect this neutrino and also in collider sense again to the Darmatter because at the end of the cascade you were obtaining a neutrino that was stable and was a lot of miscellaneous energy and that was easy to be detected. This was the situation at the beginning of the century things changed really because neutrinos we know that are not massive they are massive and they like to mix a lot together. Of course you could have a lot of extension of the standard model where the only thing you do is to give mass to the neutrinos and you want to make them to mix together and you have a better and better experiment. There were no evidence of the Darmatter and this was the situation in the 2003. You can see here that the guys who were exploring the experiment were exploring tension minus 6 picobar. There was also an experiment called Dama that was claiming that the Darmatter were there and people were very optimistic that in the first decade of the 21st century will appear the Darmatter but the situation today is this one. These are the updated constraints from different experiments and you can see that now we are in this is 10 to the minus 9 picobar. Remember the last plot? You were in 10 to the minus 6 exploring that region and now you are 10 to the minus 6, 10 to the minus 9 and we are close to the neutrino background that is going to be very difficult to make an experiment there. Not impossible but difficult to make an experiment there. The situation is incredible. Incredibly in the sense of the experiment the experiment has improved a lot and now we have checked all this region. This was a lot of effort for part of the experimentalist but the situation for the third company is a bit depressed because we don't have a detected Darmatter in the colliders appear the Higgs. At the end the Higgs is there. We complete the standard model point of view. The Higgs is more or less of the order of what you are expecting supersymmetry that is close to the mass of the set but it's a bit higher for the minimal suppository standard model Higgs but it's still consistent with the minimal suppository standard model Higgs. The problem is that the experiments also in colliders are putting a lot of constraints but still these constraints are reasonable. We are talking about TV exclusion limit in supersymmetry particles and this experiment do not cover all the parameter space. They are for very specific models for instance for the constraint minimal suppository standard model and they are putting constraints especially they are in that specific model or that specific region of parameter of the minimal suppository standard model. Still we don't have a lot of luminosity we need to wait really to have better statistics and the good point is that the u-breaker parity things change a lot. You don't have any more of this stable particle giving missing energy. A lot of constraints are weaker and then the point here is to ask the question we like minimal models because minimal models give a clear idea of which is the phenomenology you expect but perhaps we were too much minimal let's say because the model we construct perhaps is too minimal and with this question in mind let's review which is the situation what we have instead of fields we have super fields because we are in supersymmetry then we have of course the gauge group s u2 times s u3 times u1 and you have the left hand and now our super fields and you need to add two hexes and this is the simple thing to do is to have the minimal suppository standard model is this here is to say ok first we write the complete super potential which is allowed by gauge symmetries and you get these two lines here but the minimal suppository standard model to say ok this line is forbidden because of the parity and you have only this here ok but let's think a bit why we are forbidden the other terms because this is too much in principle the ones that are allowed are all of them this one at least this one in red must be not there because of proton decay but only this one in principle these are these two terms that we don't like it very much because in principle they are introduced to the new problem that is they are terms with dimensions in the super potential that in principle we understand easy if we say that that is zero or that is a big scale but when we need this to be ordinary to a weak scale or less we start to not understand why that is there then really in principle the simple thing to do more in the philosophy of supersymmetry that is to not have this new problem to not have that with dimension of mass because we don't need it in principle in principle the soft terms are the ones that are breaking supersymmetry and in principle are the only scale you need the scale of the breaking of supersymmetry but you need to forbid this because this one in red because you don't want to have a proton decay of course but you don't need really to impose our parity and to have only the first line then the idea is to say okay let's do that let's put the things that are in principle the more natural more simple and when we observe is that these are the terms this has a problem because there is no mass for the chargino and this is a problem because this is already screwed but also there is a symmetry here that is that you see what is in magenta and in blue you see that you can interchange L and HD because L and HD has really the same quantum numbers under a gauge symmetry they have the same quantum numbers then in principle you could say okay this could be called an L4 this is another super multiplicity of leptons this in principle could be done but you have the problem to what you do with the HU HU in principle has no interpretation here but this is something that is allowed because the quantum numbers of L and HD are the same okay then it will continue with this philosophy and we say okay but wait a minute we know now that the neutrino has mass and really we look to this we look to the spectrum we see that looks more symmetric we include the right-handed neutrino then let's include the right-handed neutrino and we solve the mu problem now because we are going to generate the mu term with the vacuum spectrum value of the right-handed neutrino and then the charcino is going to be massive but also we can make the interpretation that what we really have is here a lepton and a right-handed lepton now this interpretation is completely allowed we see the first line here the three families this three family leptons are the chiral ones and you have the right-handed part and now adding this right-handed neutrino this is more symmetric and really we can make the right interpretation that the HU is really the right-handed part of the four family of leptons that are lector-like that is the right-handed part it's also a tablet under SU2 and this looks very symmetric this is really what we can write it's exactly the same we are not doing anything the only thing we are doing is to reinterpret make a right interpretation of things and then with the right interpretation of things the superpotential looks very, very simple this is the superpotential but this superpotential is equivalent to the one we wrote before it's equivalent to the one we proposed in 2016 a physical regulator with Carlos Muñoz that is really, it's only to say okay, let's solve the new problem including right-handed neutrinos but also making this you can make this interpretation the interpretation that the hexes are really leptons remember this here it's only this then let's talk a bit about the phenomenology of this model because this changes completely the phenomenology not the phenomenology of the minimal supersubstantial model first of all one has mass for the neutrinos the neutrinos we know that are massive they like to mix together and the mass for the neutrinos goes with the CISO here the only scale is the scale of the supersubstantial vacuum and then because of this you are obtaining a CISO at Electroweak or TVSK and then this parameter the chukawa, the neutrinos must be ordered to the minus 6 10 to the minus 6 is more or less the same, it's the same order of the mass of the the chukawa of the electron and then the looks consistent, looks nice looks that we are not doing nothing different to the things we already know it's 10 to the minus 6 similar to the chukawa of the electron okay, but there is a surprise here that is when we calculate the mass for the neutrinos assuming that everything is diagonal we do not impose any mixture of the flavor what you obtain is a DNA mass for the neutrinos that like to mix this one is off-diagonal even if you are putting diagonal terms here the chukawa for the neutrinos you are getting off-diagonal mass matrix, that is in this model neutrinos like to mix and this is what we observe in principle they are not preference on one or another mixture but they like to mix they mix even when you try to not do so then this could be also a good point for the model it's a kind of prediction you are making okay, another thing is that one of the problems in the Minimum Superstitution Standard Model is that the mass for the Higgs is a bit low it's at three level it's below the mass of the set and that is not really very nice in this model sense to the S neutrinos right handed the mass of the Higgs at three level is more it's bigger and then you don't have really this problem then let's continue let's continue with what you expect in colliders in principle you could expect something like this that is a paper in preparation that is S neutrinos decaying to photons and it could be a miscellaneous energy and this could give display vertex because here herparity is broken but since you need to reproduce the mass of the neutrinos remember the Chukawa the neutrinos is very small and that makes a sort of approximate herparity symmetry and then you can obtain long life objects that is you can see display vertex in the collider of course this is complicated to see these analysis are not easy to make but this is a possible signature at the colliders and what about the armature because ok one of the fantastic points of the MCCM herparity conservation was that you were expecting the armature to be seen soon here the neutrinos cannot be the armature because it's decaying it's another leptome the hexeno is really in this interpretation you can think about it as a leptome with a lot of mass that is a direct one it's a vector like a leptome it's a vector like one then you cannot forget that in supersymmetry you work in supergravity and in supergravity you have the gravitino and the gravitino can be a armature candidate then we have in the minimal version we already have a armature candidate and you can in principle see this armature candidate and Fermi collaboration, Hermann and all the guys that are there Lineros has made analysis taking this into account and they are exclusions for the armature gravitino armature in this model we also have some works in this direction and this is something that is already analyzed and it's a possibility to see because the gravitino can go to a photon and a neutrino you can see in principle monochromatic photon is the easier thing to see and you can detect the armature it has a reasonable mass if the gravitino the mass is very small you are not going to see it but in principle you don't know the mass of the gravity then this is the idea in principle I can stop here and say ok you can make the interpretation of the leptome as a full family of leptomes but when you are making that you see this you say ok come on but this is really a leptome why not to do this why not to make this more symmetric to include a vector like work and then the picture is very simple the picture was simple for air parity conservation the reason people like very much air parity conservation because you have particles and super partners and they don't mix together here everything mixed together you are a bit lost the idea of what are you doing now with this interpretation it's easy what you are doing is always to have leptomes and quarks nothing else are leptomes and quarks with the super partners ok this is very easy to understand and if we have add the leptome why not to add the quarks and this is the idea now is to think ok what happen if we do so if we include vector like works then the super potential looks in principle it will be complicated if we take the one as we were writing at the beginning that is continue with the idea that are hexes you need to add all these terms here in red and you get here you see this is q and the qc that is the other this fill here and this multiplied by the right handed is neutrino in the Lagrangian but that is going to have a back on a protein value and then this is going to be a mass in principle you put here and this is 110 dB this is completely safe but you can expect to see it in the future in the LAC of course one can simplify this because if we work in this philosophy we say ok but these are leptomes these are quarks and we can write this very simple expression this is at the end expression for the super potential it is very simple then one can think ok it is possible to detect this quark and the idea the answer is yes you can detect it you can detect this in the LAC you can produce this vector like quarks and then this let's call it a new top and new bottom ok that the reason is here in T capital T and capital B and this can decay to the normal standard model particle that is W and every set and a top, a hex and a top and so on and this is completely allowed by experiments it is not excluded and we can expect to see this in the near future ok but really it is more complicated the Lagrangian that what I am writing here there are more possibilities these are the simplest one and we have a work in preparation in this direction let's finish with the talk saying that what we have is a reinterpretation of the heat fields where we can think that it is really for family of leptons but it is not normal for family it is a vector like for family this makes a clear idea how to work and what you expect in experiments in this model and we have asked ourselves ok if we are allowing or if vector like leptons are there why not for family of vector like quarks and that is what we have done we include it and this is the proposal now is to make this reinterpretation and to be open in mind to find vector like quarks because in principle could be there ok thank you very much for being there in the other side of this webcom ok thank you very much Daniel it was a very nice webinar so now we can and just to remind to the people that is following this webinar that you can make questions to Daniel via the chat in YouTube or via Twitter if you use the you mentioned our law physics Twitter account so if you want to make question meanwhile we are going to start the session with the people that is present here in the hangout so for the moment if someone want to start with a question please it's free to do it hi hello can you hear me hi I'm sorry my internet is not working well so I missed part of your talk so maybe you answer that question but if may ask you said that you have now Dirac like Hixinos is that right? sorry I didn't hear you properly ok I mean you said that now that you have the symmetry that the Hixinos are vector like Dirac particles so they cannot decay is that correct? no no they can decay when you have a particle conservation yes ok you have the neutrino that is the LSP here a particle is broken and since a particle is broken they are decaying and what we are saying is that really you can make the rate of rotation that really you don't have the Hixino down and up where you have really a vector like leptom ok but it mixes with the guine with the Wienos for example right? it makes with everything everything that has the same charge it wants to mix it is mixing with the leptons and mixing with everything but you need to remember that since you want to reproduce neutrino physics the air parity is broken but is a kind of approximate symmetry because the Chicago neutrino are more are 10 to the minus 6 more or less the same as the Chicago the electron but that's air parity as an approximate symmetry and then leptons and Hixinos or the 4th family of leptons mix together but not a lot in the 4th family of course they have to mix very little to avoid proton decay for instance no but proton decay we are avoiding because we don't have the lambda 2 prime term in principle you can think that the symmetry that is behind this model is a variant reality because that symmetry at the end is forbidden only the lambda 2 primes term but it will be another symmetry not necessary to be a variant reality but could be a variant reality a variant parity variant what's called a variant reality a long time ago a variant parity is a zeta 3 symmetry is a gauge disk symmetry 30 is the model of dry and retard right? yes the original paper was a paper of Ivanias and Ross no they introduced air parity and this 2 gauge disk symmetry the zeta 2 and the zeta 3 ok thank you zeta 2 is air parity and is that the people like more because for a lot of terms and you have the SP as stable but the other possibility the other gauge disk symmetry compatible with the spectrum standard model is a this variant parity is a zeta 3 gauge disk symmetry ok I have a question over here ok so how does the introduction of these new fields affect unification well we are not worried about unification of course you can add more and more vector like things and have unification that when you introduce the quarks without introducing the quarks you have unification because they must in the mcsm let's say no right because of single gauge you don't have this problem but once you introduce the quarks it's true you are worried about unification you are losing this but you have the possibility to include more and more vector like quarks as you wish because vector like things do not have the problem of introduce gauge anomalies yes but I mean how does this affect unification I mean no the cabinet are not going to unify you introduce these vector like quarks ok doesn't matter what you do you don't unify no you need to to add more vector like things you want unification or you don't introduce these vector like quarks you have unification you think that you only have a family for the leptons but not for the quarks you can think that you have unification but remember that you have unification you need to make some trick to think that it's su5 and you need to make a definition of your gauge couplings you are paying a price always to have unification so is there another question people here in the audience I'm going to take just very fast in youtube no for the moment no but also I have a couple of questions for you Daniel one is the usually when people discuss this stuff of proton decay there is a scale that is very high 10 to the 15 gb the scale for to make the proton very stable but from here from where is coming this scale no here you don't need to do so because we are not including the lambda 2 prime the one that breaks variant number you are breaking only lepton number but no variant number if you want the lambda 2 prime is 0 yeah but also there are these modeling which you can break variant number but not lepton number I don't know how is the we don't have that problem because we are forbidden the variant variation term from the beginning one possibility to think that you have this gauge that is this variant parity that forbids the variant number variation terms also this is more stable really because for this also dangerous terms that are not renormalizable this is completely safe ok ok so I have related a little bit with this in the case when you have this new reinterpretation of the quark fields in the sense of this new vector like quarks assuming that maybe in your model also you are going to suppose that gravity is going to be your dark matter but gravity is going to be your candidate in this new model you can add whatever you want but gravity is there yeah the gravity is going to be there since you don't have air parity is the most likely candidate of your model but I was wondering which type of new signature because this new vector quark flight in principle gravity could decay using these new fields in principle it's very heavy you are thinking that this vector like quark is order tv or more then not a problem for that ok because you are assuming that you are assuming lighter than that no lighter than that order tv could be because of the fermic constraint let's say 10 tv or something like that but no more than that then because it cannot be more than that you don't need to worry about these new quarks so yeah but also one of the stuff that for me was similar kind of I mean an idea not my idea in the sense the model that introduced these new vector quark lights to reinterpret hits with quarks or leptons is it possible to explain the number of families that you observe in the standard model let's say kind of using this idea or you require to go to kind of discrete symmetries or other type of gauge extractor for that I don't think so, in principle you have these three families for the standard model like let's say the chiral ones and you have this vector like family that is for family but you don't have an explanation for that it's more satisfactory the theoretical point of view because at the end you're working only with leptons and quarks but you don't have an explanation of why three families or why this strange family this vector like family but really this is not a strange one if you think really the strange are the other one because vector like is the more simple one the strange are the other ones this is the easy one I understand so I don't know this is the question that I have from my side I don't know the people from the hangout let me just check if we have some questions in Twitter or in YouTube it seems that we don't have I mean we have some many people saying thank you Daniel thank you very much for the invitation from the other people but anyway if there is more questions this is the moment to do it otherwise we can first of all thanks Daniel because of this very interesting webinar and the model is very nice very appealing so and also to tell to the people that is following the webinar and or people that is watching this webinar via our YouTube channel that you can subscribe to the channel and to get the notification each time that we have a new webinar and of course you can visit our WordPress page it's lawphysic.wordpress.com and of course we can see again in the next time for a new webinar of this lawphysic webinar series that is going to be Professor Enrico Nardi from Flascati University so since we don't have anything else to say so we can see you next time see you and thank you Daniel for everything bye