Mariana Grana - EFTs with symmetric moduli spaces: the landscape and the swampland
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This study by Mariana Grana and colleagues investigates effective field theories derived from toroidal compactifications of the NS-NS sector, aiming to distinguish which models belong to the "landscape" of consistent string theories and which reside in the "swampland." The analysis rigorously tests these theories against specific swampland conjectures, such as the Swampland Distance Conjecture and the Emergent String Conjecture, without relying on supersymmetry. By modeling the moduli space as a non-compact locally symmetric space defined by a Lie group $G$ and an arithmetic duality group $\Gamma$, the researchers utilize a mathematical framework where boundaries correspond to rational parabolic subgroups. A critical assumption of "semicompleteness" ensures that weight spaces intersect the lattice at infinite points, guaranteeing that an infinite tower of states becomes massless as the theory approaches these boundaries.
The core mechanism for determining validity involves analyzing decay rates, encoded within a convex hull known as a Weyl polytope derived from the group's representation theory. The distance to the facets of this polytope dictates the exponential decay rate of the mass tower, which must satisfy constraints imposed by the Emergent String Conjecture. By demanding that these decay rates align with physical requirements and that the spacetime dimension remains a natural number, the study narrows down the possibilities to a finite list of valid theories associated with specific Lie groups like $E_8$ and $F_4$. This geometric approach naturally limits the maximum spacetime dimension to 11, a result that emerges from the structure of the polytopes rather than being imposed as an external assumption. The resulting valid configurations are classified into simple geometric shapes, such as simplices or orthoplexes, depending on whether tensionless string oscillators are present.
Further examination reveals that while most viable moduli spaces originate from $E_8$, some exceptions exist, such as the 52-dimensional case associated with the $F_4$ group. For these non-$E_8$ instances, although supergravity or orbifold constructions can be formulated, a full string theory realization remains elusive because modular invariance cannot be verified. The analysis distinguishes between different representations of the duality group, noting that in $N=8$ supergravity related to $E_{7(7)}$, the 56-dimensional representation corresponds to electromagnetic charges while the 70 represents moduli. While group-theoretic methods can generate countably infinite families of solutions via seeds, consistency is not guaranteed for all of them; specifically, if the spacetime dimension is non-integer, the resulting polytopes may fail to correspond to any known Lie group.
Ultimately, the research concludes that $E_8$ is the only viable candidate in three spacetime dimensions when strict distance conjecture constraints are applied. The final count identifies exactly 29 distinct theories, or 33 if redundancies are included, which satisfy all geometric and physical conditions. This list encompasses both known string constructions and certain theories without established string realizations, such as those based on $F_{4(4)}$. The work successfully demonstrates how the interplay between group theory, geometry, and swampland conjectures can predict a discrete set of consistent effective field theories, providing a robust classification that bridges abstract mathematical structures with physical viability in quantum gravity.
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Okay. Well, thanks uh for this
invitation and I'm going to talk about
this work I did with Dan Waldram, my
former students, Veronica and Bernardo
who are now both in Madrid and Stephanie
who's Waldram students and came in these
papers and we're still working on future
directions which will be clear
when we discuss.
So um
the first one of the swamp plan session
first before going into this that I'm
I'm sure you all saw this uh this slide
is introduction and spoiler and uh and
everything will be here the idea and
then it's the spoiler of the results. So
I'll go very slowly. If you get this
then uh they will be then I mean I'll be
happy you have a take-home message and
then the rest I mean the how how we got
to those results is very nice uh math I
think and physics and it will be great
if you hear it but if you're not
interested at all in the details just
bear with me on this on this slide.
So everybody saw this picture, right? Is
there anybody who hasn't seen this
picture?
No. Okay, good.
This picture. So
what part of the landscape swabla? So
I'm going we are going to talk about
effective effective field theories and
what effective field theories I'm going
to talk about and these are the theories
with symmetric modulized spaces. For
example, what you get in tooidal
compactifications,
the NS of the NSNs sector, OKKR
divided by OKR * OKR quotient by the
duality group OK KZ. So this is a
symmetric model spaces and this is this
is the kind of effective field theories
that we're interested in and then the
question is uh which ones are on the
sample and which ones are on the
landscape.
We will not let me say from the
beginning we will not assume any super
symmetry even though this is a typical
modulate space that you get in half
super symmetric uh in in in tooidal
toidal compactification let's say toidal
compactifications of Taiwan or or um or
things
um
preserving 16 supercharges we're not
assuming at all super symmetry in this
in this talk which just we just require
the modulate space to be symmetric
and there are the swan constraints so
some conjectures so what are the
properties that effective field theories
have to have in order to be consistently
coupled with quantum gravity and the one
we'll be discussing is the so plan
distance conjecture which I imagine
everybody heard but let me it's
important because That's the whole
subject of the talk. So the this some
plan distance conjecture says that when
you go when you move to the boundary of
the modulate space so modulate space
will be the symmetric modulate spaces
there's always a tower of states that be
that becomes massless at least in this
exponentially massless in in this form
with a where d is a proper distance in
modulate space and n is some charge. So
there's a tower with different n with
some integer n and the masses go
exponential. So that's a that's the
conjecture
and we pro we proved it under my
assumptions that uh I'll tell you what
they are. So for symmetric modulate
spaces using group theory one can prove
the this swamp plan distance conjecture.
Then there is the immersion string
conjecture that says that the towers all
these towers is always one frame in
which these towers are either kaluta
climb modes of a compactifying direction
or towers of oscillation towers of
strings of a tensionless strings. So the
so this conjecture says that so both of
these are conjectures. This conjecture
says that these towers are either of
this form or of this form.
And then there is the sharpened
swamp plan distance conjecture that says
that the rate the these rates alpha they
have to be at least or the the
exponential decay has to be at least
of this uh of this form where D is the
space-time dimension of the effective
effective theory. So this decay this
tower should decay at least as as fast
as this.
>> Not the same.
>> It's not the same D. Yeah, thank you.
Yeah, we will use for this D we will use
T. Then here I put distance but we will
use D and in this
Yeah, I should change it here by T. So
this D is this D was the proper
distance. This D is the space-time
dimension of the of the effective
theory.
Um and then there is a so this is a
conjecture. So the names of the
conjecture never mind the
the the contents.
So um there is so this is a conjecture
and then what has been observed in all
the studies of compactifications
and it seems like a also universal
behavior from uh llian at least for for
llian of space that the behavior that
the exponentially exponential decay of
kk towers goes like this. So it's has
this piece and then a one overn and then
it measures the number of directions
that one is the compactifying. So for
kuta line of a single direction the
compact defying this is plus one for two
this is plus one half
and so these two things have been proven
in in all examples worked out
and what we will demand here is that so
we proved the sland distance conjecture
in general and then we looked at the the
alphas and we will demand that one has
so what we call emergence string
conjecture rates. So the emergence
string conjecture so we will demand that
the the towers are of attention string
of kkos and that the rates are this. So
we look at what is in all the set of
effective theories with symmetric
modulate space which of with symmetric
mod spaces which one satisfy
uh which ones satisfy this uh this uh
decay rate
and demanding this we get a finite list
of theories. would think and there are
very very few like 33 and by theories
what I mean is the group because all the
symmetric modulate spaces uh they they
are of the form C over K as as we will
see a group a representation of
particles so the particles are in a
given so for this type of uh of modulate
spaces what we get is that the particles
are in the fundamental representation
So the so that will come out. So for a
given group there is in general a single
representation where this such that this
happens and a single dimension spacetime
dimension where this happens. So there's
a final list up to some uh
up to some redundancy that I will
explain. But um so from this point of
view the the this uh immersion string
conjecture rates this this this
conjecture it's really predictive. So it
tells you out of all these theories then
only these ones can be in the landscape
or only these one satisfy this.
Are there any questions so far? Because
as I said this is the main. So do you
ask him anything about the asic geometry
of the uh uh
>> yeah so if I so what was the question
exactly if I
>> of the of the space time
of the is it flat or in the
>> you mean of space time and not of mod
space no no we don't uh we just assume
modulate space modulate space is this
and then group theory will will let us
study the boundaries of modulate space
and this is what I will to and then once
we know this but we just yeah
there's no potential this
>> no potential it's a real it's a actual
mod space yeah yeah yeah thank you for
the yes no potential yes
>> sorry I just want to make sure I
understood the emergence strain
conjecture rates are those formulas
right there
>> okay
>> yeah yeah so we
exactly so we require the to have a um
to have either. So any at any infin any
infinite distance point should be
associated with a tower that has this
this behavior or this behavior.
>> I suppose you will tell us how many of
them are known and how many are not out
of this 33.
>> Yeah. Yeah. Yeah.
>> And you insist on n being an integer
too. I insist on n being an integer and
in particular also d being an integer
which that's not I mean that's something
that one has to um yeah that one has to
impose the n being in an in an integer
will be natural in the um in the
construction because it it's related to
the number of directions here the
compactifying and that has to I mean
it's a group theory thing But the the D
being integer that's something that you
have to impose and that definitely
restricts what you can do and actually
what I'm going to say is um
well let me say it let me say it
>> yes
>> sorry can you repeat what is m and n on
the first
>> ah sorry okay so uh yeah the sland
distance conjecture is so good I I I
assume this was seen by everybody and
the sland distance conjecture as well.
So the sland distance conjecture says
that when you move to the boundaries of
modulate space there's always a tower
level by some number n. So this n levels
the charge of a tower um such that the
mass so m is the mass of this tower is
proportional to n and decays
exponentially with a distance. So it
becomes light
asotically light as you go to infinite
distance. And in this very particular
behaviors are exponentially decaying and
exponentials then they were conjectured
to be all greater than this. And then uh
and then in particular given I mean this
is the conjecture is that the string uh
the string um
the the I mean well this is very easy to
show that this is the that the the
tensionless string satisfies this is
very easy to show and um and then this
is something so the conjecture is that
alpha is greater than this alpha string
and alpha string is this that's how a
tensionless
a tower of tensionless string
oscillators. This is how it behaves and
then this is a universal behavior. It's
not a conjecture but this is what's been
observed in in all the on all the
compactification studies. So um so we
will prove this that there is a tower of
states becoming exponentially light and
then we will require this and then out
of out of this requirement. So as I said
this um this requirement is predictive
in the sense that you can single out
which effective theory satisfy that.
Okay.
Okay. So
uh so this is what I wanted to say but I
will say later so we assume locally
symmetric spaces but maybe what we are
doing is much more general and you'll
see why. So these uh non-compact locally
symmetric spaces are always of the form
can be put always of the form of a coset
of a le group a non non-compact le group
are the ones that interest us divided by
the maximal compact subgroup this group
we assume to be red so the product of
simply groups and some factors of r like
for example in compactifications of the
nsns sector there is this piece that we
we talked about and r would the dilaton
if you if you include the dilaton that's
factor
and then gamma is the duality group in
this case it's okay cases but in general
will be the duality group that that has
to satisfy certain properties and as as
we see
so because it can be written like this
it inherits all the the structure of the
group C so the symmetric in the modulate
space which is given by the gilling form
on G and the
what so what we are interested in are
the shodics and the boundary because the
in the in the swamp plan distance conure
one has to move a shic distance.
So the shicsics are very easy are these
exponential maps. So you start from some
point some element G and then you move
in some tangent direction and if this
tangent direct direction is normalized
to one then t is a fine parameter. So
then this is the what it was called at
the beginning D that um I think it
wasn't it was called so D was used for
the space-time dimension and for the for
the shic for the shic distance we will
now call it T and again you just have to
normalize this to one and then this
becomes a fine parameter that will so we
will see how how um the states the mass
of the the states how it decays with um
with t
and the boundaries. So um one when this
showics go to the boundary so the
boundaries are characterized. So first
we are going to define an equivalent
well we are going to define it's defined
um in the mathematics literature.
So this is literature from the I don't
know 20s 30 40 some something some
things are earlier um so the boundary so
two shes are in the same class if they
have a finite distance when t goes to
infinity so and that defines a point in
the boundary so a point in the boundary
is like aic
as an in asytoic class of of shix
so
Now for the time being let me forget
about the duality group and so make them
totally symmetric spaces. Then once one
put the duality group they become
locally symmetric spaces. But let's
first do without the duality group.
Then the the boundaries are defined by
the parabolic subgroups fixing the point
and uh so how is this? Let me just give
you the example of uh the parabolic
subgroups of of GL4. So
we we we move so we're interested in in
geodessics that go uh along well let's
say let's let's so these are the cartons
and let's move along some direction in
the carton. The direction in which you
move is labeled by this lambda one to
lambda four. And one can always order
them using the while group. One can
always order them in in some way. So
we'll order them in this way. Now if we
act on some element of CL4 by the the
joint action what we get is that each
value each sorry each um each component
of this element when you evolve it it
goes uh it evolves in this way with a
difference of lambda J minus lambda I
and then now if so if they are all
strictly one is strictly larger than the
other um so then these two two um two
shows. So two sorry two elements are
congruent. The only way if they have a
finite so the only way if they have a
finite distance when t goes to infinity
if that the the element is upper
triangular so all these all these things
where lambda lambda j is where this is
positive then all these things have to
be zero. So these all these elements are
are in the same asytoic class as this
some standard element that could be here
the identity the identity for example
for
uh no sorry not the identity because
we're sorry we are we have this order so
not the identity in this order
now for if two of the values are the
same then now one has a little bit more
freedom this H. So all the elements that
are of this form are in the same asytoic
class. If three are the same then you
have this and actually these are the
parabolic subgroups. So the parabolic
subgroups of CL4 are the upper
triangular matrices. This is the
smallest or or the upper triangular with
some element in the lower triangular. So
it's not very hard to see that um that
uh that this define a point uh that the
the the boundaries are defined by
parabolic subgroups. Now let's for
example let's now let's look at the
manifold the one can do CL4 or SL4.
That's an extra factor of R but let's
not care about that. If we now if we
look at this space SL4 over SO4 this is
the space of matrix. This is a modulized
space of matrix in four dimensions. And
let's just look at the let's just look
at the shodic in this uh in this moduliz
space. So we're moving in the cartana
and acting on some some element that we
call the origin of mod space. This could
be the identity. And then when we add in
this uh for this uh this kind of shics
what one has is the the radius. So this
this part is going to infinity. So the
radius of the first direction is going
to infinity. So this is a boundary point
of this form. And then one has to act
with the SO4. So it's not a point but is
the SO4 action of of this point.
The the this corresponds to two radio
going to infinity and this correspond to
two to three rad going to infinity. and
then and the off diagonal pieces of the
I can grow off diagonal pieces by
putting another putting another group C
but it doesn't they they all they are
all finite distance with respect to
having the off diagonal pieces to zero
so one can forget about the off diagonal
pieces and and think that all the
boundaries correspond to radi going to
zero one two or three these are the
different
>> parabolic subgroups
>> there's a fourth one Actually there
>> yeah if it's
>> there is the 2 plus two parab
>> there is the two well here I mean the
the
>> any partition of force
>> yeah yeah that's right I was thinking of
uh yeah sorry I was thinking of SL4 here
in which the volume is fixed um and then
the this is minus the the lambda yeah no
and and then yeah any partition so this
is up to rotation so any partition of
two is equivalent ent as a parabolic is
equivalent to this and and then here
yeah I was otherwise if uh if we are
free to move the if you really do CL4
there's the the R direction which is the
volume
okay now we introduce the duality group
and we're going to demand what
um Matilda
and and collaborators
called us being compactififiable. So
it's a um there's an argument that uh
that quantum gravity amplitudes are
finite if the modul spaces are what what
they call compactififiable and this
means that a volume of a geodessic ball
of radius r grows no faster than what it
will grow in aidian space. So in aidian
space this bo thish volume will be r to
the dimension of the space and they said
okay let's call that I don't know
material why compactifiability I don't
like this terminology
>> I mean yeah at best flat and then all
the others are finite volume so we had
the finite volume example that it's not
it's not right now
>> yeah so yeah it's not compact but uh and
and indeed the finite volume actually
here comes
comes out immediately by this
compactifiability.
They are finite volume because in
general for G over K the the volume of a
shodic ball of radius R grows
exponentially with R. So this is some
norm of something like the highest root
is something that is is non zero.
So it grows exponentially with R. So the
only way for this to be uh the only way
for C over K and divided by a duality
group to be uh to grow linearly sorry
power law with R is that R cannot uh
that R has to be bounded that you cannot
um you in in geodessic terms R is
bounded and then this and it was shown
that then if R is bounded then this has
finite volume. So basically the modul
spaces if one assumes if one assumes
this which they argue about the finess
of quantum gravity amplitude so makes
sense as a as a conjecture as a swamp
plank or landscape conjecture let's say
then for symmetric modulate spaces it
means that the duality group should be
such that this has finite volume and
this means that the duality group has to
be arithmetic what is called arithmetic
which is just uh to be to make it simple
like CLN CLK Z if we're looking at the
groups can always be embedded in some
CLKR and this is like CLK Z
but this uh brings a lot of uh mileage
because if gamma is arithmetic then the
spectrum trans that usually transforms
in representations of the duality group
now this extends to representations of
the group
So from now on we can forget about the
duality group. We know it's there and
it's very important and and there is a
latis and this and that. But because
this is arithmetic which is a
consequence of this requirement then we
can talk about representations of the
group C.
And then this is important because the
duality groups are not the same for
example in
well we won't do eerotic because we will
do the split form as I will say but in
compactifications of the super symmetric
eterotic and the non-super symmetric
erotic group the the duality the duality
group is not the same the the latis is
not the same but it doesn't matter here
for for for what we are doing it doesn't
matter
question
>> so does the fact that in this context
the compact reliability implies the
arithmeticity.
Do you see this as support for the
original conjecture? Can you have people
thought about the extent to which that
might be expected or not expected in
quantum gravity and therefore this is
telling us something about whether the
original conjecture is correct or not?
Yeah, I think uh yeah, this was
surprising uh to us that this is exactly
um I mean and this was
yeah this was discussed uh before that
uh um that the the the that this volume
grows exponentially and the only way
that uh that this is uh
yeah that this can grow power law means
uh means that Then this is finite
volume. So the the the I mean I think
the the non-compactness and finite
volume it's I'm not sure it's a
conjecture. So you know better what
exactly what's conjecture
I'm not but uh the fact that model
spaces have finite volume um well I'm
not sure has a name as a conjecture but
>> in all the cases that had to do with
this by duality group it was always
finite. Yeah.
>> Yeah. So yeah, rank one things are
always an exception. But yeah, when
Yeah. Yeah. And then Yeah, I think that
Yeah, that tells you about the the
duality group. the the duality group
should be such that this these modized
spaces have finite volume and that that
should be true in general but
I think
so here it's a I mean yeah here it's
very easy to to to
determine whether something is a good
good duality group or not in general for
for general mod spaces
I don't think there's such a
there's such a crit there such an easy
criterium an easy way.
Okay. Now so so now once we put the
gamma in before the the the
boundary points were fixed by some
parabolic subgroup and now the relevant
thing are the rational parabolics. And
maybe one way to see it is uh from the
simplest case which is SL2 over SU2
which is like the upper half plane and
so if this acts so if if these groups
act on by fractional linear
transformation the standard here there's
only one parabolic subgroup which is the
one upper triangular there's nothing
else you can do and this parabolic
subgroup fixes the point at infinity and
then If you do so rotations on this then
you get all the all the real line. So
the boundary of this is the real line.
So be before the gamma right before the
duality group is all the real line and
the point at infinity.
Now once you add once you add the group
in what happens is that first this is
not the real the whole this is not the
real line but is the the the rational
points which are dense but uh but still
these are these are the rational points
and then what happens is that with any
SL2C
one can go from one rational point to
another with an SL2C. So any rational
point is equivalent by SL2C to any other
and the and so that means that here the
boundary is I infinity and um and and
that gives you an idea I'm not sure that
really uh with that you can really
understand in general but why why
up to the duality groups then the
important piece is the rational part of
the of the parabolics of the parabolic
subgroup but this will be key in uh the
fact that it's rational parabolics. This
will be key in showing the the sump plan
distance conjecture once you have the
duality group in
okay and then yeah and then the once you
have this then the you can the the you
can draw the fundamental cell which is
the one the one we all know and it has a
single boundary point which is infinity
high infinity.
So
the also something that is interesting
is that the only shistics associated to
rational subgroups reach the boundaries.
The other have energetic motion. So for
example this is well known for this case
that if the B field is not rational then
you keep bouncing bouncing bouncing and
you never go to the boundary. Only if B
is rational then you can eventually go
to the boundary. And that has to do also
with I mean that has to do with this
rational rational parabolic subgroups.
Yeah, you you keep doing SL2C
transformations and uh and you stay this
way. So if you want to go to the
boundary, you have to start from a B
field that is rational.
Okay. So now to the sland distance
conjecture
that the clock is
so so this is the conjecture and so
first we're talking about states that
become massless so we have to so states
there's a spectrum of states and the
spectrum of states is is representation
and representation of the group because
everything the representation of the um
of the duality group extends to
representations of the group and if the
representation acts on Rn then one can
think of the latis as as CN Z
and so this is all the possible charges
we're not we're not going to assume
completeness that all the charges are
there but that this the spectrum of
states is some invariant subset under
this some subset that is some subset
that is invariant on the duality group
so for example if for OKK Okay, the
charges are momentum and winding and
then the populated latis could be some
sublatis of this like states which have
purely momentum or purely winding. These
are this is invariant under
under SL2Z
and um so so again so we are going to
assume something assuming that you have
all the states could be assuming
completeness we are going to assume
something that is a little bit weaker
than completeness. So, so far this is
not an assumption. The spectrum should
be uh should be something that is
invariant under gamma.
We're going to assume something about
the the spectrum.
And now the mass of the states in some
invariant function of the charges and
the moduli and this depends on the
representation. So let me do the case of
OKK
because people are familiar. So the
masses of momentum and winding states
can be computed using this generalized
metric that has the metric and the B
field inside. So that gives a n / r 2
and then m * r² and then the b field.
So it's some function like this and this
function is some invariant of the of the
group of the duality group. Now this
generalized metric you can you can split
in vine
like here using the vvine for the metric
and and the inverse and if we call this
thing so this is this is called the
momentum. So this is the momenta that
depends on the charges and on the modul
here are the moduli. So the the the well
metric and and field moduli. So this uh
this this is the dress momentum or or
actually for the the for the nar latis
these are called in general these are
called momenta.
So in general the mass square has to be
some invariant function of the group
some invariant of the group some
function of this momenta and now we
assume two things one that the function
is analytic which might not always be
the case um
but we can discuss that and then we
assume that one state becomes massless
at the boundary. So um so remember the
slandista conure is about the tower of
states. So we are going to assume that
there is at that point of the boundary
there is one state becoming massless. So
at that point on the boundary one cannot
have this constant state this constant
term and you start from a from p squ
and
>> why do you need to uh assume that a
state becomes mass boundary? because
otherwise this doesn't work.
this uh um yeah you you
mean this so
this is true
sorry
so one can expand one can expand this
assuming it's analytic one can expand
this in powers of p but uh to get rid of
this constant term you need to assume
something otherwise uh um that could be
a constant term there. Uh so in general
this is so in general what you get this
p square and this is the invariant uh
this is the group invariant the cmir
invariant of of the group um but why not
a constant I mean it would be weird to
have some constant term in all the
>> yeah but
you're trying to prove some general the
question is what assumptions you have to
make in order to
>> Yeah. Yeah. So I said
>> this is a very important assumption
because if you put it there it's the end
of the conjecture right
>> I I I agree. So I said at the beginning
prove that there are mild assumptions.
This is one of the m these two are the
two of the mild assumptions. There will
be another one
soon.
Yeah maybe you don't like to call it
mild. You you think it's strong but I
mean just to otherwise I mean what we
say can be said. So there will be a
tower of states become with who for
which this will go to zero that we can
prove and then if there's a constant
term then they as to this constant the
world states as to
>> there's no version where you say since
you have a compact space and you look at
uh things that are analytic
by some general analytic function
theorem I either the function is
constant everywhere or it needs to have
a zero for example is that else.
>> No, I
>> logic like that.
>> No, I don't think so. Um,
yeah. No, I don't think so. Uh,
I mean, but well-
compact. It's compact. That's why I
don't like the terminology of
compactifiable.
So uh that that gives you some mileage
but you cannot use the the the theorems
of compact
manifold. So um so
I don't think so but I don't know maybe
so yeah indeed. So one this is these are
two of the assumptions which you can
call mild or or strong.
I mean it would be weird that the states
go to a constant uh and also
um
it's at every point in modulate space I
mean well there are points when this can
be when this can be um
when this can be important but at all
the boundaries of modulate space the
masses go to a constant that would be
very weird.
Okay.
So
and again to to understand how this is
let me again use the example of OKK and
in particular O22.
So this is the generalized metric has so
if I I'm interested in so moving along
the cartons because the rest doesn't
gives you finite distance and here the
cartons there are two so you can you can
have only two rad going to infinity.
This is these are the inverse radia and
the states are momentum and winding
states. So in general you can write so
here is very easy to see but this is a
general formula. So your charges your
the space the spectrum is divided into
some weights under the
h
under so under the group. So the the
state each state has a weight and then
the the the way it it behaves from I
mean this term the way it behaves is in
this form. So for a given so each one so
for example and and this has to be
normalized. So we have to have this. So
for example, if you take the cartana, if
I'm just growing this radius or the way
we wrote it, yeah, if I'm just growing
this radius, then uh
then the well the states that will
become massless faster the leading tower
are the states that have momentum along
this direction. So this is a yeah this
is a general formula of the shics just
because I mean we know how the shics
are. We know that we just have to move
along the cartons. The rest will go if I
grow some pieces in here, I will go in
this direction. And and then the way we
choose these lambdas tells you which
boundary point you go. You can take R1
to infinity or R2 to infinity or both.
Um
so if I take just R1 to infinity, then
the leading tower will be this. And the
the weight of that leading tower we call
it omega star. So this is for a given
age. So it depends in what direction
what what rad you're growing for a given
age. Um there is a there is a decay rate
that is a um that is the maximum the I
mean you you see for a given age you
take the weight such that this is this
is maximum and that way we call omega
star
and this is is very nice encoded all
this information in a convex hull and
this uh this formulation we're going to
use and we're going to get mileage of
This convex hull is that was worked out
by by Jose calron and Valenuela is that
this set of alpha define a convex hull.
So for example, let's take the three of
SU3.
So the the tower has this decay with
this inner product of the weight and the
carton. The inner product of the weights
and the carton is given by these bubbles
which is called the the alpha hal. So
this for for an h this bubble gives me
the projection of h along omega and
which one is the leading so for a given
h like again I'm taking r1 to infinity
which one is the the weight such that
this is maximum so depends on the h but
if h is along any direction here then
this will be the the this will be the
the weight this was this will be the
weight of the leading tower
and these alphas then are larger or
equal than the distance to the convex
hull. So these bubbles which measure the
the the decay rate are larger or
distance larger or equal than the
distance to this convex hull and this
convex hull is in nothing else but the
wild polytop of the representation. So
using this then we get a lot of mileage
that these alphas are given by the
distances to the to the wild polytope of
the of the representation
and that's how we got I mean all the a
final list of polytopes because now now
we're interested is in these distances
and given requiring that these distances
are what I want them to be then uh then
it gives a finite list of of theories is
so now the before going into that the
proof of the swamp plan distance
conjecture.
So how do we prove so we assume that
there is one state that becomes
massless. So how do we prove that there
is a whole tower? Well, we have the
latis and then the the space the the
space on which the representation acts
is h is divided into weight spaces and
now it's not it's very easy to show
because the boundaries are associated to
rational parabolic subgroups that these
slopes are rational that these weight
spaces they um they meet the latis in an
infinite number of spo of points. So
assuming that one assuming that the
function doesn't go to a constant and
it's analytic then you have an infinite
number of states in this weight space.
Now since if we were if we were assuming
completeness then this will be the whole
story. We're assuming something a little
bit milder than completeness
which is that for all the vertices in
the wild polytope the so there is no
state um for all the vertices in the
wild polytope then the the the
intersection of h of the latis with with
this with these spaces is the same as so
basically that these spaces are
populated um
this is a bit milder than complete if
but I don't know it maybe it's less
intuitive so one can think of one of our
assumptions so we call this semico
completeness um if you assume
completeness of the spectrum then it
just goes through because of this
parabolic uh this this rational this
property of the rational parabolics
so and this is true for any boundary
point so for any boundary point there
will be this infinite number of states
becoming light and becoming light in
this in this form.
Okay. So now to the um prediction. So
it's quarter to three. I might skip some
things and and go to the result. Let me
just explain a little bit what we did
and then maybe skip some um some
details.
So again the question is what modulate
spaces satisfy this what we call
immersion string conjecture rate. So
there they are um particles that decay
and decay in this fashion and we are
going to do this from the convex hull.
Now the convex hull. So when you measure
the distance to the facet the the so
this the distance of the complex hal is
extremised at this point at the vertices
or at the middle of the facets and this
h the the so what so this extrema should
correspond so this this extrema
corresponds to a weight. So in the case
of uh in the case of SU3 or SL3 this
this correspond and I'm moving or and
and I'm making one direction in one
radius to infinity then this will
correspond to the this extrema will
correspond to the kuda line tower that
has momentum in that direction
and so that should be kuda client tower
I I call it n plus one because it's
simpler to keep where n is the dimension
of the facet So a point here corresponds
to one. So dimension zero corresponds to
a facet one dimension and it's a kooa
client tower of one direction going uh
going to infinity. Then this middle can
this middle will correspond to two
directions going to infinity because
this line is like r1 is equal to r2 and
they're both going to infinity.
So we require that all the I mean the
different facets according to the
dimension have this this distance to the
center and the last facet the last co-
dimension one facet could be either
kaluta client or string it could be a
tower of kuta client states if there are
only kaluta client states and if there
is a string there's a um there is a
point in at infinite distance so if the
daton is inside our modulate space there
will be a point where there is a
tensionless thing. So for the last facet
one can require this or this but it says
that all facets are at the same distance
are equal and so they are regular
polytopes
and they are very simple just so because
if you do the the the difference between
a facet of dimension n and n plus one
this d disappears and there's a relation
so the polytopes are very very simple
the the you get simplex or orex
depending whether you have a string
a string um a limit where the where the
tension string goes or not but they are
very simple these are classified not
many is is very nice now what makes
things uh
what what now for the full polytope so
these are the facets of the polytope for
the full polytope and this this is where
D comes because this was all about
distances between a facet a a a point
the distance from the difference between
this distance and this distance let's
say but the overall distance to the
center now it's related to the dimension
and here we have to put the requirement
that the is a natural number and this is
what uh really boils down to um a finite
a finite list and there's a unique
dimension for each for each of these
each of these polytops. So the
requirement that D is natural. So as a
you were saying and natural comes here
because it's a dimension of the facet
but even natural is not a natural thing
that comes out. And the nice thing well
this rank polytops agree with this.
The nice thing is that the list of all
the polytos that appear actually with
this are realized by one. So are the
wild polytopes of a given group. So all
the so in a sense
maybe all we need is that the boundary
is a locally symmetric modulate space
and we don't care about the bulk and we
can show this very generally. Um there
are these polytopes for um that realize
the different boundaries and what's in
the middle we don't care. And then yeah
we didn't um I mean we we work the other
way around. So looking at the polytopes
and satisfy this and put this and this
is natural and going case by case but we
could have done the other way around and
then see the final list of polytopes and
ask code. So we once once we knew the
result and then when we had this result
cloud wasn't so cloud chip PT wasn't so
powerful but uh then once once once we
had this then we asked CHP and then it
is yeah they're all realized one given
that provided is a natural number they
are all real there so they're all the
wild polytope of some representation of
some league group so um that's why I was
saying this might be much more general.
Okay. So, effective field theories in
the landscape. So,
uh one thing is that we assume that
there is a so we assume the split form
okay K for simplicity. So, split form
means this that the real rank is the
same as the complex rank. So, we're not
doing K + 16 for example K. um we I mean
we're we are thinking of it we're doing
it now but uh we haven't done it for the
for the paper and then we assume that
all the vertices are at the same
distance and that means that particles
are in a single representation of of
row. So also another obvious future
direction is to is to relax this
condition and look at what happens with
there are multiple representations
and uh well let me know I mean if
there's an factor then it's very easy to
satisfy this you put this these very
regular polytopes at some point from the
center and then you you can realize all
these groups in any dimension so these
these groups once you have the R factor
then you can realize this in any in any
dimension because you you use I mean
this is where you put the the center. So
these are a little bit of of a cheat.
The nice thing is when these are factors
inside like in the exceptional mod in
the in the exceptional modulate spaces
where the the dilaton is is inside the
the group
and what we get is this only these
polytopes satisfy
only this I think there are 11 polytopes
satisfy the requirements and each of
them is realized by two three or at most
five different groups. So these are all
the groups
and and the representations
that you can have in the landscape. This
is the I mean that's it. Anything else
except for example that I'm going to say
but everything else is outside the
landscape or does not satisfy this um
this uh
immersion string conjecture rates
one. So there are only 29 theories. So
with a four before that we had before it
makes it 33. And one interesting thing
is that if you look at the maximum
dimensions. So for example uh this
arises in three dimensions
and it's rank three. So you can
decompactify
this up to six dimensions and you cannot
go any further because there are three
directions you can decompactify. And one
can never we didn't put this 11 that the
maximum number is 11 but this comes out
this is not an assumption but it comes
out that you cannot decompactify up to
more than 11 dimensions
and then well we see the E87 E6 E5
deceptional theories and there are some
some theories that we don't know the
string construction for example F44
neither of them we know the string
construction
But um yeah, let me say so we could in
principle get it. Um so yeah, one
important thing I'll say quickly is that
actually
for every for every point in the table
there's an infinite family because you
can you can
you can multiply the highest weight by a
number and divide. So there's a symmetry
of the system which is multiplying the
highest weight by this uh number p and
dividing the dividing the the inner
product the metric and then you get a
bunch of representation for example for
C2 you get the seven the 27 the 77 they
are related by this so actually if this
is possible then all these series is
possible and we don't know of some
arguments such that this is not allowed
h you change the curvatur
but uh I mean we don't know of a
principle I mean maybe one can put some
plank uh plank like it shouldn't be more
curve than one over plank square or
something like that but yeah I I don't
know so
this up to that subtlety
then the point is whether all these
these theories are related and the
answer is mostly yes there are slices
from each other so slices of the type of
orifold
that arise in the dimensions or slice of
the type of decompactification
and yeah let me skip the details but as
polytos they are all related so one can
all these are slic slices of this but
once you put the representations in in
uh inside it's not true that they are
all related and if we look at the
threedimensional the ones that arise
sorry not threedimensional ones but the
ones that arrive in three space-time
dimensions. What we get is that most of
them come from the eight
but there are very few of them that
don't. So this don't come from that and
uh so we don't know if string
realization and doesn't seem to be uh
some string realization if they don't
come from this. There are others like
for example this f4 with a 52
we can so it comes as a modulate space
it can we can construct it as an orifall
or a u fold better of this so that it's
not hard to to construct and this is we
don't know if the string realization of
this so we could give you the moduli
space realization or the super gravity
realization of this but this doesn't
tell us that uh it was it's a U-fold so
we cannot check I don't know modular
invariance for example of that so we we
can construct again the sort of the
super gravity realization of all these
mod spaces but that's not necessarily I
mean doesn't necessarily mean that there
is a really string theory
real a string theory construction
>> okay
this representation In all of these
examples in subra these are the vector
multipliers and under this
representation of the duality group or
>> this is a representation of the so this
is a represent
so the the group here is a duality group
and this is a representation of the of
the particles so since we are not
assuming any super symmetry um it's a
the representation of scalar particles
>> for instance the e77 which is like n= 8
to grow in four dimensions. I think the
56 is the vectors.
>> So yeah, E77 but we so E77 is not here,
right? Because this is the So let me go.
The 56 is the is the particle. It's not
the vectors. E77 is yeah the 56.
>> I think the the scalers are in the 70,
right?
>> The sorry this is the
Yeah. So it's not the scalar. So this is
these are the states with momentum
winding. Uh and yeah if if you if you
want these are the
yeah so these are not so the the the 70
are the moduli and these are the states
that have momentum or winding in the
seven. So if you start from M theory
these are the states that have a
momentum or M2 or M5 brains wrapped on
the parts and the cycles of the Torah.
This this is what forms this 56.
>> It's just electromagnetic charges.
>> The electromagnetic charges. Yeah,
exactly. The electromagnetic charges.
Yeah.
>> Okay.
Okay. So, yeah, I was at the
conclusions. Uh so, okay. Assuming
semicmpeness plus assumptions that
some people don't want to call mild and
the the rates. So we we show the SL plan
distance conjecture and then given that
the the the
requiring this distances to be this the
we have a final list of uh of groups and
a final list of polytops and they all
have realizations in terms of regroup.
So they're all the while polytop of
irreducible representations and uh well
every solution comes in with this
countably
infinite theories and um the coming
families generated by a seed. These
these are things that I say they should
we should with this we can give the
realization of some exotic modulate
spaces but it might not be consistent
and there are three families in three
dimensions that will come from E8 which
are this and I leave with the the
introductory the introductory picture of
of the landscape.
Thanks.
>> Right questions.
>> This D that appears in alpha the square
root of D minus 2 was that supposedly
related to the dimension of something
originally or
>> so this is the dimension of space time
but
>> it it seemed to not be related to the
dimension of spacetime at all. It was it
came from the schol
it's also the space time dimension in
any way or is it
>> so it it turns out to be I mean so what
you get is that E8 is only possible in
dimension in space time dimension three
so it cannot be um
>> that was gravitational input or that's
all pure
>> no no that pure I mean we require that
the distances are this and then d comes
out and d comes out to be what it it is
in all examples that we know,
>> right? But there was no but your group
theoretical construction up here we had
no reference to any dimension
whatsoever. no no okay and did you did
you uh you assumed that d was integer to
to call that
>> so yeah as I said we did this in two so
when we did it we did it in general
trying one polytope after the other blah
blah blah and yeah assuming that d was
integer then once we knew the polytopes
uh actually we then we asked CPT okay
what are the polytopes that satisfy this
simplex or complex plus DV natural a
natural number and then it came out uh
that that they are all associated
they're all the Y polytops of a of a
group
>> but but just purely group theoretically
D could also not be an integer
>> based on your input like the assumptions
that you made
>> yeah yeah yeah I think D cannot be D is
not necessarily any integer and then and
then it's not going to be I guess my
guess is that it's not going to be the
well polytop of any league group if D is
not an integer but I'm not sure I'm not
100% sure but definitely yeah this D
does not need to be an integer once I
mean if you do this purely from the
group theory
>> all right let's take other questions to
the break and we reconvene in 15 minutes
maybe a little less