 Am I supposed to to be hearing something Nicholas? Okay, I cannot hear anything. Okay, I think Nicholas is in mute, but I Think well Walter, okay. Can you start representation? I think okay, and then sharing too. Okay. Well. Hello, everyone I'm very happy to be here and thank you to Nico for the invitation. I love this this Program of the webinars every week talking about particle physics to special that America but everyone else So today I'm going to present. I'm gonna start screen sharing the Hope it is this one. Okay, and then I have to go Okay, I'm going to to talk about a work that I did with my collaborators in Tel Aviv University with Kosaku Tobioca Lorenzo Baldy and Tomer Bolanski and This was a painful project for like that lasted quite a long time. So finally it's it's out and we gave it the name of a relaxed inflation and It has to do with a continue some Work that was introduced a couple of years ago by Graham Kaplan and Regendran Where they presented another solution to the hierarchy problem. So as we know The hierarchy problem Has to do with the fact that when you consider the standard model as an effective theory Then the mass of the Higgs is not natural in the sense that it's too small for the cutoff that the natural cutoff that the theory should have and and they and there has been a Very large variety that were beautiful works for the last three or four decades of people Presenting different types of solutions to this and they go by the name of supersymmetry extra dimensions a large extra dimensions a Technic color twin Higgs composite Higgs and they are beautiful models and beautiful physics is that what we have learned with this but the majority of these type of solutions they require the introduction of new degrees of freedom at the lecture week scale and Now it's been many years so for several years of probing this energy scale at the at the LHC and nothing has been found So in view of this these people proposed a solution where No new degrees of freedom are introduced at the lecture week scale and instead the solution relies on the dynamics of So the scalar field that is like an action That is true. It's a couple to a strong group similar to QCD for example that effectively produces a cosine potential and And of course that is coupled to the kicks And if this theory is going to be natural then the mass of the kick should be naturally the size of the cutoff of The theory so this lambda here is the cutoff of the theory and Then the Lagrangian written completely or the potential of this Can be written in this way and you see that there is here some effective new term that can be either a Positive or negative depending on the value of fine So the whole idea is that during inflation although fine in this case episode the scalar field It's not the inflation in the original model The idea is that during inflation five is a The rolling very slowly So you have a very flat potential and and there are two different regimes one regime this effective new term is positive So electric symmetry is exact and then basically You have just that five is rolling and the wiggles from the QCD are not there Or the wiggles from the effective Potential for the so the scalar field because this guy is proportional to the level of the Higgs But if the electroic symmetry is exact there is no bed for the Higgs So these are these terms actually not there. So that's what I didn't do the draw the wiggles here So is a five is learning is It's slowly rolling and then at some point when there's me effective new term becomes zero Then the like after that electric symmetry is broken because the new term is negative. Then you have legs spontaneously Spontaneous breaking of the symmetry and then the wiggles appear and then you have the wiggles here and then as as the the Action of the relaxion now it goes over the wiggles at some point There is some condition that it has to be satisfied and it's the there is a minimum of the potential Now you take this and this and that And you take the minimum of that a That is basically given by this condition and Which can be more or less translated to this condition of the parameters Then at that point the relaxion is going to be stuck. He's going to stop and And then the question is where this happens and you if you if you look at the effective new term at which For which this happens you see that it's naturally of the order of the electroic symmetry of the electroic scale and then and then that a sort of Explains why the mass of the keys is so small even if the cutoff of the theory is a much larger An extra condition that we need is that there is at least one wiggle between the point or where the Symmetry breaking happens and where the Relaxion stops and that is a given by this condition now There are ready with these conditions that we have here and with the fact that we are in inflation But that five is not the implant on there are several consequences That were found in this original paper one of those has to do with the fact that because any source mode the Excursion of five during all this process is going to be much larger that the plank scale So we have transplanted motion which is not ideal, but it's not something that you it's not something Rare you find it very often in models of inflation, but anyways, it's one of the consequences Another consequence is that there will be many e-folds I mean here this doesn't say much but to give you an order of magnitude in the paper They found that you should have at least 10 to the 45 e-folds. So that's quite a lot The third consequence has to do with the strong see pre problem And it's basically the fact that Due to this and the the action the action was introduced in physics because we wanted to solve the CP problem the fact that That we measure a theta a theta parameter that is very small, but here if I get say stuck in some point of an a generic point here then the spec it gets an expectation values that is afforded of F and the effective setup a Parameter is going to have a value that is of order one and that is no I mean that basically reintroduces the the problem that the action sold in the first in the first safe place and then the the fourth a Issue is that the cutoff after you after you Taking to account these constraints and that the energy density of the in store in this So the scalar field cannot be larger than the energy density of the Inflaton because the Inflaton is what it's driving the dynamics of the universe During this epoch then a that imposes a cat that the cat of has to be smaller than than 10 to the 8 10 to the 7 a There is a GB missing here So So it's like it's much larger than the electric week scale. Yes, but it's I mean It's not so large. So what we When we read this paper and we were discussing in Tel Aviv, then we wonder can we do better than this? but can we do better we mean a First can we actually obtain some subplankian motion? So instead of transplankian excursions and the answer I can give it later, but I can give it now to answer is no so then we looked at the For us the most important issue is that it when the CP problem is you they knew in the original paper, of course And and the way that they solve it is to introduce an extra an extra strong group with some new fermions that That are key then so and and then and then this theta is not a is not the theta of the QCD and and That's a that they avoid any issue with QCD But for us the most important issue that has to do with them with naturalness is the fact that we don't have a large enough cat I mean what happens? I mean, can we make the the cutoff as large as the plank scale? And this is going to be the our main our main goal in the in the in the paper, but with that it comes Also a very And this for us a relevant question is can we make the in flat the implant on and the relax on the same field? Instead of playing with two fields at the same time during inflation Can we just have one that plays two roles the implant on and also the relaxation? so that we want to do and And then on our way we found that there might be something important that that is that is already present in this In this toy model, but but that was maybe overlooked or the people didn't pay enough attention to that and is that This place here is important in the sense that it's a place where particle production Can happen due to the fact that here there is an enhanced This is what they call an enhanced symmetry point because the muscle that he's become zero When we start to look in a particle production, we do I like that particle production during this process can be relevant Oh one hand to reheat the universe if we want fight to be the implant then we need to think about how to reheat the universe but on the second hand a It might provide dissipation that helps for the slow roll as especially at the end of inflation And then we don't have to rely so much on the flatness of the potential so after going around many times we arrived to proposing a Relaxing model where the inflaton is the relaxion and now it's coupled to a u1 photon For now, I don't I don't want to specify if this photon is the standard model photon or Or a hidden photon, but it's just an ability is a muscle s we have a muscle s a vector gauge field and And it coples to the to the relaxion If it's till the term and this model was a studied Years ago by by Amber and Sorbo And and then also when we write this model then we want to solve the question emotion that we can write In this fashion here this is the conformal time and I have introduced some redefinition for the velocity wait by the By the hobbled scale that is what the hobble a parameter that is given here and this a dot B comes from from this term a Where this? Brackets here they just refer to the heart approximation where we are integrating over the this is these guys are written in Momentum space and you are integrated over the phase space And So we want to solve this to end of course this you can see that looks just like the like the standard Equation of motion for the for the inflaton except that now we have an extra term here And this is the question of motion for the for the photon of course with the two polarizations, but notice that here this term that is some sort of a efficient a effective frequency It has a peculiarity for some small very low values of k of the momentum For some a values you have that this frequency that is frequency squared is going to be negative That would would imply that there are some modes that become tachyonic This is something that is seen in many places in in particle production during cosmology that there is some Non-perturbative production of particles that is Exponential enhanced due to the tachyonic instability of these modes, but notice that is just one of the modes, right? The one I mean this case in this notation a minus So and indeed they quit a solution to this equation of motion for the tachyonic mode when psi is large enough when it's larger than one Is that the most growth exponentially? Which implies that this that the energy density stored in these photons are being produced a Gross also exponentially and this term that will then back react in the equation of motion For phi is also growing exponentially. So after I so now we want to exploit this a Exponential production of a photons to see what we can do in terms of the relaxation and reheating the universe So with this I can give you what what our picture is we have several regimes here at the beginning We have the slow roll so we have a very Very flat potential that is written here and we here we have the linear approximation of the potential So in the beginning we have that the symmetry due to the mu term being positive The electric symmetry is exact and we are just slowly rolling at some point the effective new term becomes negative And then the wiggles appear the wiggles from the cosine potential But then we still We are producing photons, but we are having we haven't produced Enough so during this regime the question of motion just looks exactly like the slow regime a slow roller gene that we Started in keep the garden where we just these two terms equal to zero We can ignore the second derivative and we can ignore the production of photons here but at some point the photons are produced enough and And then it's actually these two terms that are important And then I'll show you how what the solution to the question motion is for this case a in a sec and then at some point there is enough energy stored in photons such that it actually is Larger than the energy stored in the in the inflat on at that point the photon starts driving They start driving the dynamics of the universe and we call that the reheating and there is some some relaxation period here at some point the Inflat on the other election stops and here is crucial that we will have to to add a constant to the potential such that That we tune the cosmological constant in the same way that you're doing hybrid inflation or other models of inflation You just tune the cosmological constant to be the the observed value of the cosmological constant and and then that's where our Our dynamics ends So in the first in the first regime, we have slow roll. We define the standard Slow roll parameters. There is nothing new here It's easy to satisfy for the small values of the of the parameter M that we had in the in the morning But I won't go into details here because this is a standard a Story the important thing is that at some point this This regime is is what is going to be relevant because we are producing we have produced and we are keep producing enough Photons so here the equation of motion and leads to a solution where Sight and remember that it's parameterizing the velocity of the speed of of phi It's give is just growing exponentially. So here you can see how we go from one regime to the other Initially, you are growing. I mean this is the you are slow rolling, but But but this but you are sort of spinning out it's been up a little bit But at some point when size of order 10, I mean, oh, yeah 10 to the one a You we go from the regime one to the regime the second regime where Where now the photons are the ones that drive the dynamics and the slow roll and it's actually even more dissipative than Then the slow roll from the put it from the flatness of the potential and phi and the velocity is pretty much constant this XI also logarithmically and And then at some point we want to reheat There are there are several constraints here that were started previously by by a Sorbo and company on one hand and collaborators of Peloso and on another side and it's that a This is this is incredibly nice that we have so much dissipation from the photons But then there is a problem with the generation of the of the fluctuations the curvature fluctuations or any inflation due to the if these guys start Dominating the dynamics early enough and what by early enough I mean Many faults before you end inflation then you generate very large fluctuations and then and then these fluctuations not only will Be incompatible with the with the size of the with the scale of the power spectrum Measurement in CBA by a CMB experiment But also there will be many of the densities that will that will collapse into primordial black holes And will they will create an abundance that is incompatible with what we see today so we want to avoid the if we want to evade these constraints then we need to require that that a That this doesn't that this transition here doesn't happen many Ifos before you any inflation and that's why we have this Transition in our case. We're going to set up such that it happens not earlier That not earlier than than seven or ten Ifos before we end inflation. So so the perturbations that we see in the CMB They are in this type of low-scale inflation. They are generated at 30 or more ifos before you we end inflation So so that's why the fluctuations that you generate during this regime that are very large They are not they won't show up in the CMB nor will create a Primordial black holes that are too large and incompatible with what we have a measure so After and then so we are reached this point where we have to reheat So we have to reheat the universe and this is where actually for us at least the things became more interesting because you have a You have an exponentially large number of photons, but they have a peculiarity the Momentum is very small. You have a huge Occupation number with a very low momentum and that's what we call in physics are classical electric field So indeed you're producing lots of photons But effectively they are they are not behaving as a gas of quantum photons quantites photons But they are just behaving as a classical constant electric field and Then the way that we reheat the universe is by by doing by looking at Non-perturbative effect that exceeds in quantum electrodynamics. That is the swinger effect When in the present zone of a very strong electric field you can create out of the vacuum you break the vacuum You create a prostitute and a electron And the rate is Unsuppressed once the electric field is much larger than the than the mass of the of the electron square so so in this case then You transfer all the a lot of a of the energy of the electric field into the electrons And then the electrons are also accelerated by the electric by the constant electric itself and they will start colliding and Then they they will thermalize and and this is a type of reheating that for us it was more like a surprise in the process and We hadn't seen before Started in the literature and when the energy that is transferred into the electrons is afforded or of the energy that was in the photons then We have a thermal bath that will give us a temperature of the order of the of the of lambda not that is a The the size of the potential in the small we both basically so this is something similar to the lambda QCD and So this so far sounds very good except that there is an effect that we hadn't taken into account here and is that a If this photon is the photon from the standard model then They will thermalize very quickly with the photons that are being produced and Then once you produce what once you have a thermal bath then there is some screening mass some divide mass for the for the photons that will kill the tachyonic instability and then you kill the particle production of photons and then And then you are not to hit in the universe the maximum in this case the maximum temperature that you can Obtain for the reheating for the reheating temperature is afforded of the mass of the electron that is not enough for bbm so the way that we went around this was to To introduce a dark photon instead that has a tiny couple into the electrons that here we parametrized with this Kappa, I mean the full coupling we just call it e kappa and And then in this case This guy is a couple and we clean up to the electron such that they don't thermalize fast enough The photons the electrons will thermalize among them Serves but not with the dark photons and then and then when the electric field because we can produce very large electric fields There is no problem with producing a much much larger electric field than than in the case where we had the photons at the standard model and then And then we will we will still be able to use the schwinger mechanism to produce a pairs of electrons and positrons and And then and then we need to require first that the electrons That the photons don't get a thermal mass that is given by this condition here, but also we need to Make sure that that we don't we don't we don't suppress the schwinger effect In the sense that in the sense that the shrink it this rate has to be fast enough so that a that we can transfer the energy and And then during this time the relax on is still a slowly rolling and And at some point we reach again this condition that we mentioned at the beginning where we stop and and at that and then we We end our dynamics and notice that and like in the first day in the original model here The relaxation of the stopping of the relax of the relaxion happens after you reheated and after you exit the inflation And so so then with all these dynamics then we can look at all the constraints we have we have a six Parameters in our in our theory. We have the coupling To the fall of the relaxation to the photons. We have a the the size of the wiggles we have the well the this is this is also this also the the Characteristic scale of the the characteristic scale of the of the decay rate of the of the of the Relaction and then this was the slope or of the potential is the flat potential the cutoff of the theory and the coupling of the dark photons to the electrons and On hand we need to be we need we need to have so since we want to have the cosine potential We need F to be just larger than the cutoff of the theory And This constraint came from the fact that we needed to have at least more than one wiggle between Between the symmetry breaking point and the stopping of the of the field and this one came from the fact that we need to have as as more enough Flatten of potential such as you can stop at some point a When when this condition is satisfied and and this condition comes from what I mentioned that you want you want to have the the second regime the photon production regime a We want to enter that regime Not too early so so that we are consistent with C and B constraints But also we want to enter at some point this regime. We don't want to enter this regime before five stop after five Should have stopped. So so it shouldn't be too late. Basically Usually, I mean we require that we enter this regime before inflation ends. So at least a few e-falls a Everything of inflation happened while while the photons are driving the dynamics So all this basically all these together they give us this region of the primary space these lines the Red lines are the ones that are the values of the coupling constant of the the coupling between phi and the photons given by by this condition here This is the type of temperatures that we can obtain and we can see that we can even get t of TV or the yeah TV reheat temperatures, so that's nice And this condition of this notion get effect comes from the fact from from disinnequality because this if you see you take this guy and this guy you obtain any Condition of lambda not there is some there is some factor of psi Missing here that that basically gives that's why this is a diagonal and not just a vertical line but anyways Conditions that looks like this up to a factor of psi and then and then there are some conditions on on Experiments are looking for fifth forces and That were presented in this paper by a group from Weisman and Constraints from astrophysics in the sense that this is this coupling between phi and the kicks is Relevant enough then large enough then you would you would obtain Some extra cooling for stars and supernova and that enters here, and then you would you could produce these guys In being dump experiments, so that enters here and so So that is where these two constraints come from and this comes from the fact that the lambda wiggle that is lambda not In this case should be larger should be larger than the oh this is actually Should be smaller than the than the electric week scale that we call here. Yes, Mw So this is this is what we did We think that there that this relaction that has been around for two years now is a very interesting mechanism and And now we were we were able to incorporate the features of inflation and in some ways it sort of Brings back into the attention the what we what what has had been called in literature action inflation Because there were many constraints from action inflation due to the perturbations and everything but but but this is a nice realization of action inflation And where now the action is not only the inflatum, but also the relaction that the stabilizes the the The mass of the kicks and notice that it seems the only condition is the lambda is smaller than f We can have lambda that is the cut of the theory as large as 10 to the almost 10 to the 17 gb So that is very close to the Planck scale Just one of them I need to be low That is many orders of magnitude about the original model that was only like around here So we were able to obtain a very high Cut of that was our our original Purpose and then in in our way to this to get to reach in this point We realized a particle production, especially this tachonic instability features a That this is crucially in reheating of course and can be used also as and for a dissipative effect at the end of inflation because a Of the back reaction of the of this energy density into the dynamics of the of the relaction And and then there was the nice reheating process that we sort of bumped into About using the schringer effect And that if you use I mean if you use it carefully without I mean taking into account the thermal effects You can you can you can use it to reheat the universe And now we are working on the on like more specific Details of this and we hope at some point we can present it later this year And And that's it. Thank you very much I mean, I don't know if you guys actually were listening but Let me see. What do I do? Okay Thank you. Walter. That was great um, okay Okay, so you guys listen. I don't know if people are hearing Yeah, I know everybody heard the only problem was that on Nicholas, um Microphone died. So I'm going to so he did an introduction for you, but it's it's it's silent Oh, okay So what I'm going to do is I'm going to open the floor for for questions From the audience here, and then I'm going to go over um, the twitter And also the the google hangouts page to see if there are any questions from the audience That has been watching your seminar and are not here. So but let's first, um Let's just ask What are any questions that we might have for him? So I'm opening the floor for anyone here Okay, so I think nico last whose microphone is dead has a question and so he's going to type it up and I'm going to just Say back to you go ahead that nico Okay, his question is basically From the introduction, uh, why do you want to avoid and not too large cutoff? well, I mean the That that is the purpose of Presenting a pro a solution to the hierarchy problem If there is no new energy and up to up to plank scale and no new degrees of freedom up to plank scale then then you should Of course 10 to the 8 gv cutoff is it's a it's a nice enough cutoff if you want to explain why the Why the the mass of the case is noted to the 8 but 10 to the 2 but But I mean ideally It would be nice to have but but so what happens then we've got Theories for example, let's suppose that we believe in that So so then the reaction is the original reaction Morel is not good enough. I mean it's not efficient. Yeah, it's not good for For stabilizing the mass of the hicks if if there is energy or if there are new degrees of freedom at 10 to the 16 gv So we wanted to just push it as large when the the higher the cutoff At least from our point of view the more efficient and the and the nicer Disconstruction is I mean if there is something Who's which goal whose goal is to stabilize the mass of the hicks then the higher the cutoff the better the model no Yeah, in essence, you would want the cutoff to be the plank mass, no exactly that that would be yes We couldn't reach the the plank scale, but I mean 10 to the 17 is good enough Yeah, well, yeah 10 to the 17 is pretty high up there Um, I do have one question really quick. Um, what happens? How do you deal with this cosmological constant tuning? Isn't that just another tuning? Yeah, this is not different from from the cosmological constant tune the tune of the cosmological constant that you do in other in in other inflationary models You always need to make sure that at the end the the vacuum energy is Is zero. I mean pretty much zero Uh, so that's that that's why I mean in any in any flat potential that you write for any any inflationary model At least for most of them you have You have to set the zero at the end of inflation Right the zero of the of the of the potential is It's at the end of inflation. Otherwise you will start with with cosmological constant. So so the I mean there is some there is some quick analysis that you can do of Because it's true that that that there would be some worry that What we're doing here is sort of cheating because we are tuning the cosmological constant in order to Tune the the the weak scale. So it's like we are double tuning, but it's not it's not deep I mean in this case it's not It has nothing to do with the two of the of the of the electric scale It's just it's just the the normal tune and if you if you take one of these measures of like how much tune the model is This is basically as tuned as any other model of inflation Okay, so in this case it's not that we are transferring or even increasing the tuning It's just the normal tuning that we have in inflation But isn't it do you think do you think it's it's I mean, they're totally unrelated, but if they were related, wouldn't that be a natural kind of Oh, yeah So at the beginning for for some time we actually thought that that they were related that by tuning the cosmological constant We are setting the electroweak scale and in that case it would be even better because yeah Yeah, but but but at the end we realize that That that no that is not what's happening at some point We were excited because we were saying okay good So given give me a solution to the cosmological constant and then and then that Turning the cosmological constant will give you the solution to the electroweak to the hierarchy problem But but that is not what I mean. Yeah, it's not what is happening here. Okay. It would be nicer But but it's not do you think are you going to explore any models which can Accomplish that or or it's just an yeah, I think that I'm not allowed to say I'm not allowed to comment on that Okay, all right Okay, so now I have two questions from from from the audience here watching your seminar Well, the first one is what are the constraints for the the side field for side? No, I don't know Yeah, okay. So XI is just XI is a redefinition of the velocity XI is a Is five dot divided by f times h where f is the you know, it's the coupling of the of the Of five to the photons and h is the Hubble parameter. Uh, the constraints are well, there are more constraints except that Well that during the slow roll of course, XI is incredibly tiny because Because five there is no much kinetic we are in slow roll regime. So it's very tiny And and then and then it does grow but it won't go it won't go beyond Of order 20 because after you enter the and this this happens that it gets of order 20 during When we enter the photon the photon driven dynamics But because the because it grows logarithmically then it won't grow it won't grow much larger than 20 And and then at some point we just reheat the universe. So and five will stop. So just XI becomes zero and And there is no That's that's the end of the story for XI Okay And the second one are are there any constraints on non-gaussian uh gaussianities Well, the construction of gaussianities are basically the same that are that that come for that that are present in in the action inflation papers But but here they actually don't since we are entering the photon driven dynamics Only the last five defaults they won't affect the The gaussian and non-gaussian distributions of the perturbations during that that we see in the cmb because these guys are going to be generated Uh in this case, we are talking about low-scale inflation and in low-scale inflation The cmb what we see the fluctuations that we see in cmb. They are they enter They are produced. They are there They come from like 10 to they from 30 to 35 defaults before the end of inflation Not 60 like in the I mean in in in high-scale inflationary models so So far I mean we haven't explored deeply this question of the non-gaussianities we we didn't compute the the power spectrum coming from from from this part from from We have the photon driven dynamics but But the most constraints that that apply to action inflation apply to would apply to this inflationary model if the if the the photon production regime And when the this regime is dominant If you enter this regime Much earlier than this but then by entering so so late We are evading this so in our case in our case We are we don't care about our this regime so much for the inflation part But for the relaxation of of the lecture week scale part But this happens anyways after the end of inflation. So we only care About entering this regime just in the in a couple of faults before we we end inflation And then this this one affect this one affect the cmb with non-gaussianities Would you mind showing your your plot again the archive or the cybers? Who's uh cybers of the e-folds plot? Yes, I I don't mind. Oh, no, I don't mind Hey, let's Can you see I can you can you see? Yeah, I can see your screen. Okay Ah, yes, echo Uh, yeah, so see for example here. So you're a size growing indeed. This is the velocity But but you know, it's growing only because the velocity is Defy is speeding up just a little bit. But also the hobble because we are slow We are going down hobble is growing is is decreasing. So excited just grow But then in the like for example in sorbo's paper so amber and sorbo and some papers by peloso or Or a few other groups that have explored this this regime would happen like in in In 30 e-folds, for example, like around here But then in that case you produce the power the size of the power spectrum the scale of the power spectrum is like Oh For the fluctuations are four orders of magnitude larger than what you see in cmb So in that case, that's why that's why that's why many people discovered this type of models early a Early in the like a few a few years ago But but because they were trying to they were trying to avoid having a flat potential But so they could they wanted to have just like a very steep potential or an arbitrary steep potential And and then and then the dissipation would come from the photons, right? Meaning photons are giving you dissipation. You don't care about the flatness But then the problem is that if you are relying only the on the dissipation for the for the rolling of the of the inflatone During during the relevant e-folds for cmb, then you are you are this is ruled out Basically, so so nicolas says, okay, so I guess I kind of probably answer this question So so the flat regime corresponds to the epoch when the dark photon dominates them Hey, no, say no, you have to say that again the flat regime The flat the regime number two in your in your plot Hey, yes. Yes, exactly exactly when yeah, it's this regime right the way the solution is logarithmic. See Yeah, yeah, yeah, right. So that's why I call it regime two is this yes this Is this regime here? Yes. Okay, and then I well you're you're we're getting some more questions here. So one one question is so From from the audience here that the mechanism Breaks parity symmetry. Are there any sizable signals on on this model from? You can put on the cmb again again if if the cmb is In the fluctuations in the cmb That is that that that that generated around again If we were already in the second regime here, like for example in sorbo state but again in that case Yes, there should be because you are generating more one more one polarization more than the other So you should see you should see Some breaking of the parity there. So there would be you will see one polarization more than the other But in this case again the cmb that we see today The the fluctuations coming from this regime We don't see them in the cmb. They don't show up in the cmb Of course, I mean it would be nice if we if we had this this parity breaking Show up in the cmb because that would that that would be uh I don't know survival more one more Definitely, but unfortunately now We can we can see it All right, and one last question from inicio santos terra the temperature on the end of the reheating period Yes, it's sufficient to suppress the creation of monopoles Um It's sufficient to suppress the creation of monopoles I don't know how to answer that question. Okay monopoles come monopoles coming from the from the dark you one Yeah, and let's see Let me ask initiatives Which monopoles here refers to? Okay So we'll wait till uh, uh, Benicio's rephrases this question, but is anyone here in the audience? Would anyone like to ask another question? So you have additional fermions in your model? Uh, well, so the yeah, we would need additional fermions that they can be Very heavy in order to get because we are now we are talking about these dark photons Yeah, we need we need anomaly to couple the to couple five today to the photos He's one we have the strong dynamics. I mean if you want to avoid the the the the strong cp problem then You need a strong c a dark strong a group Yeah, no, yeah, but so which which I mean, I don't know if you said this already, but uh, Can you can you probe this in the lhc? Well, there are constraints there are constraints for On this coming from so there are constraints from not finding in the lhc That that that is included here in the Oh, where am I again? Okay. That is included in this in this a Orange. Yeah, so what is it? It's orange a region here, but But I think that the production the production Prospects in the lhc are quite limited because of the Of the smallness between the in the coupling between these guys. I mean m m this this value is very very small Is it's not it's natural because once m goes to zero then you recover a symmetry because for this is the scanner But but it's very small So so here's a crazy question So you you're basically saying that the inflat on is this action, right? Yes, okay how So so can you can you probe this model through top through any topological? um effect in neutron stars or or or sort of mediums that are really uh, strongly coupled and topological in the sense. I don't know like I mean, if it's an axion then it has some sort of topological coupling right to to matter Yeah, well, the yeah the fact the if it's still uh, um I think we can discuss this later, but I mean I'm interested in this topological effect. So probably we could talk about Yeah, so yeah, yeah, you can you can think about about because this this guy is absolutely scalar Then there are many things that you can think of doing with this a That people have done with actions, right? But but this is a very different action, right because the f well f can be much larger But also I mean the I mean the the effective mass of this guy is incredibly tiny I mean if you think like, uh, yeah the effective mass of these guys Is incredibly tiny, but anyway, we can we can discuss a Yeah Days later So so I think Vinicius hasn't uh, rephrased the question. So maybe perhaps we can follow up with you Later on, um, so if there are no more questions, I'm gonna just give you a little I like to give you a little brief Intro that probably no one heard. So so just to remind everyone Walter is I graduated from the University of Texas at Austin cool town um, and he will now be a faculty at Colgate University in New York, right? Yes, and Uh So we will have them we will have him teaching next generation of undergraduates and doing research with them and he will be also collaborating with people in Cornell Um, Walter has just he's finishing a postdoc in the University of Tel Aviv And um, I met Walter a while ago in Argentina. I do in one of my favorite, uh, Summer schools that I've attended. So and I've also worked with I've had the pleasure of of working with Walter and In a paper. So so I want to thank you Walter for this really nice seminar Um, no, thank you guys. It was it's great that we have this This space. Yeah, and if you can pass out if you can pass around and you know this This to anyone else who would like to talk to send us, you know, send them Ask them if they want to participate. It would be nice to have Many many other speakers around the world So with that I'm going to you know close today's webinar and we hope to see you all next Next time Thank you Walter. Gracias