Thursday, December 3, 2020 1:00 pm
-
1:00 pm
EST (GMT -05:00)
Title:Twisted Hopf algebras
| Speaker: | Loïc Foissy |
| Affiliation: | Université du Côte d'Opale |
| Zoom: | Contact Karen Yeats |
Abstract:
A
twisted
Hopf
algebra
is
a
Hopf
algebra
in
the
category
of
linear
species.
The
Fock
functors
allow
to
recover
"classical"
Hopf
algebras
from
twisted
ones.
Numerous
constructions
and
results
can
be
lifted
to
the
level
of
twisted
bialgebras,
such
that
cofreeness,
shuffle
and
quasi-shuffles
products,
etc.
Using
two
tensor
products
in
the
category
of
species,
we
define
the
notion
of
cointeraction
of
twisted
bialgebras.
Examples
on
finite
topologies
and
graphs
allow
to
reconstruct
Ehrahrt
polynomials
and
chromatic
polynomials
in
a
canonical
way
from
cointeraction
of
twisted
bialgebras.