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Can you see this?

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Yes.

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So then let's get going. So yeah, thanks
everyone for dialing in on your Saturday.

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And I hope everyone is doing as well as
possible given their challenging

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circumstances and so on. So I was asked to
tell you a bit about some recent or less

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recent theory developments in dark
sectors. And so that's what we're going to

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be doing. So you can start by asking a
question, what a Dark Sector is. And if

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you're doing the first thing, which is to
Google this, you'll find a remarkably

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unhelpful answer in the sense that
Wikipedia says that it's a collection of

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unobserved quantum fields and their
corresponding hypothetical particles. So

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that's not it gets a little bit more
specific often done, but it's not really

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particularly helpful for what we want to
do. So I'm going to operate on the

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following definition where a Dark Sector
here means an extension to the stone

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model, which does not carry stone model of
quantum numbers. causes you to be cross

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you want. So in this Venn diagram, you see
the space of obvious and theories, where

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the gluing electroweak, you know, and so
on are stuff like our visible corner of

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quantum numbers from this time model that
are visible. So this is not Dark Sector

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and everything else counts as a Dark
Sector in this definition. So the Dark

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Sector may or may not contain a dark
matter candidate, but that's not

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mandatory. And sort of for the purpose of
focus, I will talk only about accelerator

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applications of these models. There's a
lot of cool astrophysics cosmology that

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won't be addressing at all today. Even in
this with these caveats. This is of

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course, a huge chunk of literature and
I'll be neglecting large chunks of it. So

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my apologies in advance for that. So this
is a bit of a cherry picked set of things.

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So first, I thought it'd be useful to
maybe elaborate a little bit on like, what

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are the two schools of thoughts in my mind
that are In the theory community when we

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think about these things, so the first set
of theory priors you can adopt is that of

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minimalism. So in the sense that you take
the same model, and you try to extend it

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with a smaller set of particles as
possible, maybe one or two new particles,

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but a very small set of couplings. And so
minimalism is really what drives your

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motivation here. So in theorists talk
about simplified models, or portals, this

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is usually the type of thing you're
talking about. The other school of thought

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is, is a realism, as I would call it,
which is where you're really trying to

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address a particular problem in the summit
model, like a hierarchy problem, talk

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matter or whatnot. And so these models
tend to be much more elaborate and much

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more intricate and they tell some sort of
story, rather than just like a set of

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particles. So at the risk of beating a
dead horse, I thought it would be useful

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to very briefly remind you of the pros and
cons of each of these two approaches,

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right. So in minimalist scenario You have
a very few a fairly limited set of options

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that you could be pursuing. Because
there's only so many ways you can extend

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this model with one or two particles. The
models tend to be simple, very low

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dimensional parameter space. And that
makes them really great for benchmarking

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and for comparing one experiment against
another. So that that's, that's, of

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course, a plus. But it's also I put it
also in the negative column in the sense

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that it's very easy to get carried away a
little bit with this if it's not careful,

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because of the convenience of projecting
everything on two dimensional parameter

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space. So this is something we always have
to be mindful of when we do these things.

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And then there is the obvious downside is
that there is no a priori, deep motivation

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as to why these things have to be there.
It's just something that you can consider.

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For the realist models, the theory of
motivation is there. So there is like a

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specific problem that you're trying to
solve and that means that these models

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have much more predictive power. Dan, the
minimalist model in the center, so

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specific question that you're seeking the
answer to And that gives you a prediction

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on the parameter space. The downsides are
that there's a huge number of these things

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like order a hundreds of these each year
of being published. And so it's very, it's

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somewhat unmanageable in that sense. And
often in these models the parameter space

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as relatively high dimensional, and that
means that it can be quite difficult to

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rigorously falsify them. So my personal
view on this is that a model independent

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approach to dark sectors because it's such
a nebulous concept, is is probably not

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possible. And if it is, it's very
difficult. And in that light, I think it's

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important that we balance these two
schools of thought and relying too

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strongly on one of them is can be
dangerous and we could be missing things.

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So here is a cartoon of what a journey
through the Dark Sector could look like

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for us. So we live on the standard model,
which is this continent on the on the on

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the bottom left, that's really nice.
There's all our stuff is there. We Have a

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good time, and lots of interesting things
to explore. But we want to see what is

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beyond. And so if you're interested in
minimalist models, so I think the analogy

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is that these are things that live in the
shallow water around our own island in

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some ways. And so here are a few examples
of models that you see show up and

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glitcher. Very often, the more realist
models that we compare with, like islands

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that we see in the distance, and they
require a boat to go there. And to explore

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in some detail, there's a bit more rich
structure on these things. But they're a

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bit more often a distance and we're
basically relying we can come up with

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anything. And so I'll be discussing a
little bit both of these. So let's start

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with a minimum of models. So you will and
the upper right corner you always see the

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art depiction of what I'm talking about.
So you can see which class models I'm

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currently discussing. So usually a single
sort of archetypical a minimalist model is

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just one single new particle that you
connect to the standard model. And so

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there's a production mode and a decay mode
that comes with that. And typically the

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couplings of these things are fairly small
just because of experimental constraints

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that already exist. And so, that means
because these couplings are very small,

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your production modes that are most
promising are either exotic decays or very

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narrow Standard Model particles will
elaborate on or situations where you have

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a very, very high part on luminosity
function for this initial state over here.

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The decay is also quite intricate and is
quite interested in the sense here you see

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sort of simplified formula of what the K
the K width of a particular particle might

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look like or achieve some coupling
constant m is the mass of the particle in

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question and m is some heavy mass scale.
And then m here is an integer that this

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positive in the church depends on the
particular model in question and so So

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from this structure, all the key
amplitudes will will look like this. You

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see that if this mass scale over here is
fairly heavy because we haven't observed

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any of these new particles yet. So this is
of the order of a few TV or so that means

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that if this light particle over here, the
thing that you're actually looking for is

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in the roughly gv mass range, you can you
generically expect that this this weight

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is very small and that you have long with
particles in this context. And that really

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informs the way we look for these these
models, at least in this low mass range.

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So let me Oh, and then yes, because we are
in sort of minimalist mindset, you get

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bonus points if your particular model
predicted decay and production vertex

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which are the same, so if it's the same
vertex, then that's considered better. So

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let's first show you one example of where
you have very high Barca luminosity which

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could be in So this is a nice result that
was updated earlier this week by athletes.

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It's the light by light scattering and
ultra virtual heavy ion collisions. And so

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here, the photon photon luminosity
function is so enormous because of the

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high charge of the ions over here, that
you can actually fuse two field photons

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into a light action like particle which
can indicate back into two photons. And so

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that here are some limits produced by both
Atlas and CMS. On the mass of this is the

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mass of the particle. And this is a
coupling constant, you can probe pretty

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small coupling constants, and the world's
best limits on this scenario are currently

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coming from heavy ion collisions, which is
kind of interesting. sort of more

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bicurious scenario is where you're
producing one of these light states

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through the gay of a standard model
particle which is very, very narrow. And

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so I picked this particular example from
any 62 because it's recently came out a

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few weeks ago. We are looking for a heavy
neutral laptop. And so this is really a

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neutral fermion which makes us with a
standard neutrino. And so with below the K

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on mass, you can produce it in this in
this particular decay over here. And so

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really what they're taking advantage of
here is that the K on itself is an

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extremely narrow particle in the standard
model. So that means even a very small

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coupling like you can see here down to 10
to the minus nine, you can still have an

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appreciable production rate for this
hidden set and neutral laptop. And,

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of course, if you're Atlas and CMS, the
last thing you want to do probably is or

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LCD is to pick a fight with any 62. When
it comes to a key on the case, however,

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you have some heavier particles at your
disposal, which are also very narrow,

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which are the beam as ons. And as tight
multix. I will say very little about the

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Higgs because I'm not going to talk about
that in the next session. So I will be

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largely silent about this. But just to
give you some motivation as to why we

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carry here you see the number of particles
produced in the house. luminosity Elysee

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versus future Collider, like the ILC. In
some optimistic scenario or belt two, you

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see for all the heaviest particle
particles in this model, the high

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luminosity, by far has the largest
production rates, many orders of magnitude

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in some case. And so again, because the
Higgs and the B are so narrow, they're

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really excellent targets for us to look
for hidden sector particles. And so

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really, the challenge is, under what
conditions can we overcome the trigger on

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background challenges to the extent that
we can leverage this this addition this

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increased production rate over some of
these more cleaner experiments like a

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future lepton collider or dumbbell to
experiment? And so that's really the

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challenge that we have to be thinking
about. So one great advance in this

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direction, I think is the concept of data
scouting. So what you're seeing here is

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The sort of famous diamond invariant mass
plot, that every experiment in history so

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far has been made as made in some way one
way or the other. But really what you're

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what's special about this CMS one over
here is that this was done with a data

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scouting data set. And the threshold for
the neurons was was only three gv so this

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is basically low as you can go for the
neurons to still reach to your chamber.

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And so I think this type of analysis has a
lot of potential to look for hidden sector

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particles. On the same node, there is the
whole data data parking concept where you

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save some of the data for later
reconstruction. And so in particular, CMS

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has already attempted a 10 unbias beam as
on tape. And so that's something that we

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should be looking into. But for both of
these cases, it's very important that some

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plan is in place before the data has been
taken. Of course So I think this is where

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we have the theory community should engage
more with our experimental colleagues to

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really try to understand what is possible
in the experimental side? And what are

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things that theorists would think we would
be looking for. We weren't looking for in

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these trigger level analyses or in this
data set. Now, so when I'm talking about

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online event reconstruction, I would be,
it would be outrageous, if I wouldn't

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mention lacp. As specific specifically,
there are new online event reconstruction

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or in the next upgrade, it will basically
eliminate the level one hardware trigger,

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and do everything in software. And so here
are some really nice studies where they

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showed that in the particular context of
this dark photon parameter space, they'll

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be able to cover very large chunks off of
the parameter space. And this is really

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thanks to this innovation where they can
do things on the software trigger.

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Specifically, they can cover what I would
call this the triangle of doom in the

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sense that that These upper gray areas are
excluded by Muslim factories. Well, this

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is the triangle over here, the gray area
is from beaten up experiments. And so this

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is a majority difficult part of parameter
space because for a beef factory does the

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production rate is not high enough, while
four being an experiment, the lifetime is

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too short. And so this thing decays before
it hits your detector. And so lacp is

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going to clean up this parameter space.
putting us in a bit of broader context. If

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you extend this plot all the way to lower
couplings. You see basically that once we

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have the lacp result, we will know fairly
robustly that there are no dark photons

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below a mass of roughly hundred meters,
because this just keeps going. All these

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other constraints keep coming in. And so
this will be very nice and very robust. So

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another thing, just focusing on a slightly
different model and focusing on CMS that

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you can try doing this, you can With the
new CMS level one track trigger that will

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be implemented for high luminosity Elysee,
it might be possible to look for these

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dark hex scenarios where you have a light
Higgs a light scalar field phi here, which

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makes us with a standard model Higgs. And
so it picks up a you call a coupling, in

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this case to the top you column. And you
produce it in these

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v penguin decays basically down to the
case of neurons in the displace vertex. So

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when you're rehearsing with that study
last year, are we trying to estimate what

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the potential signal would be for CMS for
this type of model, and you can find we

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can see that it's roughly in the same
ballpark of what lacp could record in

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terms of the number of events. So this
year with Jared Evans have been looking a

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little bit into what would be the offline
sort of offline implications for this and

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you see that you can really potentially
improve the reach for this type of model

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by by quite a lot. If CMS is To do this
now, so this is more or less all I want to

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say about the sort of minimal model
scenario. So there is a really nice review

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that we worked on last year led by a guy
on friendship maximum possible off, which

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I think to the day, that's really the most
comprehensive overview of minimalist

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models, especially in the context of both
in the context of experiment and theory,

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where a lot of things were compared. Now
there's a very fast moving field. So that

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means that some of the things were
outdated already in months after the

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review was put out. But this is a very
good starting point for anyone who's

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interested in these things. I also want to
advertise a small virtual workshop we'll

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have in a few weeks, where many of these
things will be addressed in detail, so it

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does interest you and I encourage you to
sign up for the workshop. Now I will now

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switch gears and talk more about these
more complete models which are attempting

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to address one of the users We'll be
questions that are plaguing us with a

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standard model, what is the dark matter
biogenesis, and so on. I think you're all

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familiar with what this says. So let's get
started on like these three particular

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examples is, of course, many more, but I
had to make some some choices. So let's

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talk about how symmetric dark matter and
biogenesis. So the really underlying

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question is, why is there more matter than
antimatter in the universe? And so the

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question, this question was answered in a
sort of, pragmatic point of view by soccer

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off in the 60s is like, if you want to do
get Baron, a symmetry that's large enough,

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you need some sort of CP violation, some
out of equilibrium process and some amount

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of barrier number violation. Now, it turns
out the standard model has all of these

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things. We have a phase in the CPM matrix,
we have an electric phase transition and

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there are electrics failure on processes.
However, if you do the estimate, you can

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show that none of these things are enough
really to create a large environment

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symmetry in In the universe that has all
the right ingredients, but unfortunately,

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in the details, it doesn't really work.

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So this means

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when you think about hidden sectors, you
put all your hopes and dreams in the

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hidden sector, which means that you can
really realize all the things that the

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standard model has the potential for but
didn't actually really achieve. And so

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here to to understand how this works, we
need to take a look at the history of the

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universe as a function of time and
temperature. So we always start very hot

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as usual. And as the universe cools on
time, all side you first go through an

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electric phase transition. All the W m z
bosons are getting a mass essentially.

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Then around one gv there's a QC phase
transition where you start condensing

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gluons and so on into metals, and around
BBN, you BBN around one and the V you

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start forming nuclei. On the Dark Sector,
something somewhat analogous happens if

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you want to realize this scenario. So
first You have a dark phase transition,

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which tends to happen at a temperature
higher than the electric phase transition.

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And you want this to be a very strong face
position. So you can generate lots of

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large enough barium, barium number in the
Dark Sector. So the next thing that

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happens is that that barium number in the
Dark Sector must be somehow transferred to

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the standard model. And then finally,
you're left over with a lot of symmetric

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degrees of freedom in the Dark Sector. And
so they have to annihilate away to the

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standard model. And ideally, that's
happened before the onset of Big Bang

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liquid census, otherwise, you end up in a
boatload of trouble. And so these last two

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steps are very interesting for us because
it means that there is some mandatory

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coupling between the Dark Sector and a
standard model for this to work for this

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cosmology to work. And so these are these
are exactly the couplings that we're going

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to try to use in order to discover these
things and experiment. So here's just a

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recent example from the group the group at
UC Berkeley. So they considered like a

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confining Dark Sector, where you have a
dark neutron with a MOS of roughly a gv,

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which acts as a dark matter candidate. And
so since they are dark neutrons, they end

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up with a lot of dark pi zeros as well.
And so those guys you have to get rid off

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before BBN stars, otherwise you will, you
will mess up the predictions from Big Bang

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nucleosynthesis. And so it is works and
their model is this dark pion will decay

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to dark photons. And then the dark photons
themselves will decay back to the standard

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model. And so you can see the parameter
space here on the right, so this is the

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same plot that we showed before the dark
photon mass versus the mixing angle. With

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the Standard Model photon This is the
triangle of doom that I talked about

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earlier. And in their model, they don't
have a specific prediction of where where

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you should live in this parameter space,
but they just tell you that well, we have

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to live to the left of this blue line. And
to the above this, this red line over

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here. So that means that the the model is
definitely discoverable, but like it's not

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strictly Speaking falsifiable at least not
in this channel in the sense that you

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could, in principle be a magnet scenario,
look over here. And this is sort of

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inherently a generic feature of these more
complicated models. That tends to be

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always like some way out. I think I need
to speed up a little bit. So the other

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problem that is interesting is the actual
quality problem. So if you're interested

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in the strong CP problem, this works
really well. If there's no, so there's a

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global symmetry of pq symmetry,
something's broken the actual fixed

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potential by contributions from QC D, and
you want to sit in his minimum over here,

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but even very small deviations from for
instance, gravity will mess this up and

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you're slightly off the center of the
potential which ruins the setup. In this

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plot, you're seeing the mass of the axiom
versus the coupling constant and so this

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line over here, as you can see the axial
line above this line, you have an axiom

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question. The problem below this line you
end up with, with the data quality problem

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that you need to solve. So there exists UV
solutions for this some additional model

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building is needing it. But there is
another interesting question is like, Can

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you make the axiom heavy enough so that
you live in this space you don't have, you

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can see the colliders but you don't have
this quality problem. And so this is where

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a doctor comes in. So if you have an extra
Dark Sector, in addition to the standard

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model, and it's connected with the axiom,
in this way, the axiom derives its miles

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both from the standard model and from the
Dark Sector. And it's still parametrically

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lighter than than the standard model.
However, if you now make the Dark Sector

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much, much heavier than the stone model,
you can pull up the mass of the action in

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this way, and solve the oxygen quality
problem. Of course, as always, there's

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some cleverness that's needed in the sense
you have to set this up very, very

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carefully. So you don't reintroduce a
strong safety problem. But there's a set

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of nice papers over here which do it so
This

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experimentally, consequences were studied
recently in these two papers over here,

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which I encourage you to take a look at.
So this is the parameter space, the axial

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inverse of the coupling constant. And here
are some projections for instance for lacp

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dye photon search, which are many
different channels that are of interest.

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The generic thing to remember is that if
you want to solve a strong CP problem, you

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must have a coupling to gluons. So, there
is some way of producing these particles.

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And you're also very likely to couple to
photon So, photon jets, which is the study

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assumption, this study is a very well
motivated signature for this scenario. So,

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the final thing I wanted to talk about is
the hierarchy problem, specifically class

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of models are called twin Hicks models.
And so this is motivated by the fact that

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the status of the hierarchy problem thanks
to the excellent work for our colleagues,

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Atlas and CMS, is a little bit bleak these
days in the sense that your stop is

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excluded down below roughly 1300 gV or so
while you're really wanting to lose Around

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500 feet. And so the question is, can you
still have top partners that are living in

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the sort of more preferred parameter
space. So this is addressed in so called

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twin x models where you have an additional
sector dice to the standard model, which

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is more or less a symmetric copy of the
standard model. And in particular, it also

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has a top Quark and, and really what's
happening is that the top Quark in the

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Twin sector serves to partially cancel the
divergence off the Standard Model top and

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this reduces the hierarchy problem to some
degree. Again, of course, some cleverness

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is required. And you can see this was
achieved in this paper and then when you

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follow papers, since. So I think the
citation history of this particular paper

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is actually interesting because it's a
very nice metaphor for the psychology of

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theoretical physics and in the last couple
in the last decade or so. So one The paper

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came out like this is well before the
Elysee, people were quite confident that

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this is a nice model and so on. So we give
you some citations, but Susie will

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definitely show up at the Elysee. So not
to concern that we discovered a Higgs. And

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then you see here around 25 members of the
barn data being collected as this spike,

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this threshold of citations are suddenly
reality was starting to set in. And the

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sort of more exotic possibilities became
suddenly much more attractive for us to

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study. But jokes aside, just in terms of a
pragmatic point of view, what are the

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implications of these type of models? So
twin Higgs models

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it's almost up. So

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I'm I this is my second to last slide. So
Twin Peaks model is is an example of a

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Hidden Valley which means there is some
confining dynamics there and some

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complicated things can happen. So for
instance, what can happen is that you have

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quarks and gluons in the Dark Sector so
you can create some dark shower Large

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multiplicity of dark metals, which then
decay back to the standard model,

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sometimes their displays are too short. So
you got this very goofy signature over

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here where you have a jet with a bunch of
this place where it shows. The general

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question here is how do we build a set of
maximally inclusive searches that can

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capture all these types of signatures with
a minimal amount of searches on the

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experimental side. And so this is a very
complicated problem, a lot of theory work

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is needed and is in progress for this. But
the current status has been summarized in

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the Longwood article white paper that came
out last year. And so it's a very nice

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subject in the sense that it combines
things you're doing along with particle

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searches with jet substructure and
precision PCT calculations as well as new

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tools like machine learning and so on.
Alright, so this is why I will will

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conclude so the one of the points I wanted
to make is that the dark sectors if you

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want to call it or like it's really like
the jack of all trades and stuff, bsm

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model, it just shows up everywhere because
it's such a incredibly broad framework in

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some way. And there's a lot of flexibility
in terms of doing things, which makes it

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also difficult to really pin it down.
There's a lot of great work going on in

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all different types of frontier. So Atlas
and CMS we talked about, we didn't mention

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much about intensity from fear, but even
neutrino experiments are contributing a

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lot to this field now. And on the theory
side, I talked about model building. But

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in the appendix of this talk, what are
some nice results and proof calculations?

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Also, production decay rates have so many
scenarios, we didn't even touch cosmology.

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Now, what is there to do for experiments
for experimentalists? I think the

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challenges are really how do we maximize
our sensitivity to exotic Higgs the case

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it's like been a case of high luminosity
Elysee to make sure that we really squeeze

336
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the most out of this. And I'm a sort of
more long term perspective is like how do

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we preserve our data for future
generations because given the complexity

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of these models, and the inherent level of
uncertainty is quite clear. possible that

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in a few decades from now, someone will
come up with a completely plausible new

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model. And we really need to find a way of
making sure that that does not get lost at

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that point. On the theory side, I would
say that we need to engage our

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experimental friends more, but things like
triggers and scouting techniques and so

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on. So they're really maximize, maximize
the efficacy of these very cool methods.

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There is a question about what our
comprehensive coverage is possible. And if

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00:27:28,890 --> 00:27:33,870
so, is that what does that even really
concretely mean? How do we define this is

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00:27:33,870 --> 00:27:38,610
a debate we can have? And maybe on a more
philosophical level is like in this space

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00:27:38,610 --> 00:27:42,270
of theories, what are we mean when we are
trying to when we're saying we're making

348
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predictions? Do we insist on
discoverability falsifiability? Or do we

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00:27:46,320 --> 00:27:51,030
do we are we insisting on need or if the
theory solves a problem, are we satisfied

350
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with it? So these are some open questions.
So I will finish I thank you all for

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listening. I hope everyone stays healthy
and unwell in these difficult times I

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00:28:04,590 --> 00:28:08,970
think the agar Eagle especially for for
helping me think through some of the

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things that were discussed in this talk.
And if anyone wants to discuss more at the

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00:28:13,140 --> 00:28:17,340
end of the session if your zoom meeting ID
and a password will be present after the

355
00:28:17,340 --> 00:28:18,360
last talk in this session.

356
00:28:20,130 --> 00:28:26,130
Okay, thank you very much, Simon for this
nice overview talk. So we have now 92%

357
00:28:26,130 --> 00:28:35,580
participants, I'm sure there should be
questions. At the moment, I don't see any.

358
00:28:35,880 --> 00:28:41,790
So let me ask you about precision in this
area. What is the status here? I mean, do

359
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you are you at one loop level to low level
QC electric?

360
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It really depends on on the specific
scenario. So for example, I can I can show

361
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maybe like, these are some two results on
the theory side that I think I wanted to

362
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Highlighted enough time for. So if you
have a dark Higgs, which is what's

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happening on the left hand side, this is
your you're trying to calculate the decay

364
00:29:08,580 --> 00:29:11,730
width of this particle mixing with the
Higgs, but it's around a few gv. So it's

365
00:29:11,730 --> 00:29:15,720
very challenging to actually do this
calculation and so you need to use all

366
00:29:15,720 --> 00:29:19,920
these unitarity methods and so on. And so
this this resolved by Martin Winkler is

367
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very nice. The theory uncertainty on this
and the few gv regime is fairly large, I

368
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mean, it's still or one and it will
probably remain, remain like that in the

369
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foreseeable future in the lower masses in
the higher models, the uncertainties are

370
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fairly small. And then on the right hand
side is the same thing for accident like

371
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particle again, the future here is very
challenging.

372
00:29:40,350 --> 00:29:45,420
Okay, I see. Thank you very much. I have
now one question. So you can talk now.

373
00:29:45,720 --> 00:29:49,260
Think of unmuting yourself. Water.

374
00:29:49,530 --> 00:29:56,700
Yeah. Very nice Talk. Thank you very much.
I have perhaps a little bit Viet question

375
00:29:56,730 --> 00:30:02,370
we had just recently, a very nice seminar
by Madison. center. And he brought forward

376
00:30:02,490 --> 00:30:08,040
the big question that how we may test that
actually quantum field theory is the right

377
00:30:08,070 --> 00:30:13,740
theory. Because if I did all your models
correctly, all the models rely on this

378
00:30:13,740 --> 00:30:19,020
very, very fundamental assumption that we
are working with a quantum field theory,

379
00:30:19,020 --> 00:30:19,380
right?

380
00:30:19,740 --> 00:30:20,550
That's correct. Yeah.

381
00:30:21,090 --> 00:30:26,160
Yeah. And and I found this intriguing
question, if we have now this tremendous

382
00:30:26,160 --> 00:30:31,020
data and this tremendous position, and you
were mentioning position, choose leaf as

383
00:30:31,020 --> 00:30:39,180
an example. Would you see Is there any way
forward also, this respect to possibility

384
00:30:39,210 --> 00:30:40,710
and this?

385
00:30:41,730 --> 00:30:46,770
This is a this is a very, very challenging
question. I spent a little bit of time

386
00:30:46,770 --> 00:30:50,970
thinking about this at some line, or Well,
let's put it this way. I had useful

387
00:30:50,970 --> 00:30:55,470
discussions with people who were thinking
about mostly at the Institute for Advanced

388
00:30:55,470 --> 00:31:02,370
Study like the one and EMA and so on and
Yeah, I mean, like so one thing that you

389
00:31:02,370 --> 00:31:06,900
know, if if you're suppose you were
measuring a distribution, let's say the

390
00:31:06,900 --> 00:31:10,950
beauty spectrum of TT by production or
something like that, and for some reason

391
00:31:10,980 --> 00:31:15,420
your your spectrum with some would be a
discontinuity, right, like so. So one

392
00:31:15,420 --> 00:31:20,310
thing one robust prediction of quantum
field theory is that you should see a very

393
00:31:20,310 --> 00:31:24,600
well behaved behaved continuous spectrum
and so on. So if you would see, you know,

394
00:31:24,600 --> 00:31:27,900
discontinuities like, like delta
functions, or just like things falling off

395
00:31:27,900 --> 00:31:32,670
cliffs, that would be strong evidence that
something very major is wrong. Now, that

396
00:31:32,670 --> 00:31:37,710
being said, we don't know how to calculate
anything, and that's an area right so so

397
00:31:37,710 --> 00:31:42,660
you might be able to consistently do a
tree level calculation. But then at one

398
00:31:42,660 --> 00:31:47,820
loop, if you're violating things like
locality and so on, it becomes very

399
00:31:47,820 --> 00:31:52,170
difficult to really understand what it is
that you're doing when you're trying to

400
00:31:52,170 --> 00:31:58,530
calculate particular observables. But yes,
there if you would see very strange things

401
00:31:58,530 --> 00:32:04,500
in the data. Like discontinuities, I think
that would be my shortstop, my first

402
00:32:04,500 --> 00:32:05,010
guess.

403
00:32:06,089 --> 00:32:10,859
Thank you. So this was presented at the
winds that we may need from the theories

404
00:32:11,309 --> 00:32:13,079
that say, just look into this. And this

405
00:32:15,179 --> 00:32:17,399
is really helpful, perhaps. Thank you.

406
00:32:18,149 --> 00:32:22,409
Thanks a lot. So we are running out of
time, but maybe you can ask very quickly

407
00:32:22,409 --> 00:32:26,129
on this question from the chat. So the
question is, what's your point of view

408
00:32:26,129 --> 00:32:31,079
about the x 17? As you mentioned, the
current exclusion limit on gamma t mas

409
00:32:31,109 --> 00:32:32,639
less than 100 MDB.

410
00:32:34,140 --> 00:32:36,330
So if you repeat the question, is it
related?

411
00:32:36,360 --> 00:32:41,940
So the question is, what's your point of
view about the x 17 x 17.

412
00:32:42,990 --> 00:32:45,240
So, this is the are you referring to the

413
00:32:46,890 --> 00:32:51,300
the the x is in the Hungarian experiment
at 17. MEP or is this

414
00:32:51,840 --> 00:32:57,390
was like it was extended? Then you
resonance? Yes. Yes. Then you resonance?

415
00:32:57,540 --> 00:33:07,350
Yeah. So There are there are two, I want
to be careful about this the theory model

416
00:33:07,350 --> 00:33:13,380
as models that you have to build in order
to accommodate this access exist. But

417
00:33:13,380 --> 00:33:18,930
that's, but they're very complicated and
quite contrived. So they don't give you a

418
00:33:18,930 --> 00:33:22,650
lot of confidence in my opinion, but this
is this is real, at least from a theory

419
00:33:22,650 --> 00:33:29,700
prior point of view. And then yeah, this
is not my opinion, necessarily, but I hear

420
00:33:29,700 --> 00:33:34,440
from experimental colleagues that the
observation itself, the experimental

421
00:33:34,440 --> 00:33:38,760
measurement is tricky and there might be
there might be questionable, but this I'm

422
00:33:38,760 --> 00:33:43,800
not I don't want to elaborate on because
I'm not qualified to weigh in on that very

423
00:33:43,890 --> 00:33:44,430
accurately.

424
00:33:45,600 --> 00:33:50,010
Okay, thank you very much. I'm sorry, but
we are running out of time. People can

425
00:33:50,010 --> 00:33:53,760
join you in the Zoom Room afterwards.
Thank you for giving your talk and I hand

426
00:33:53,760 --> 00:33:57,360
over now to Catalina Yes,

427
00:33:59,400 --> 00:34:00,000
move on to the