Title: On the power of PPT-preserving and non-signalling codes
| Speaker: | Debbie Leung |
| Affiliation: | University of Waterloo |
| Room: | MC 5501 |
Abstract:
We
start
by
considering
the
general
problem
of
transmitting
quantum
information
over
multiple
uses
of
a
memoryless
quantum
channel,
which
encompasses
several
rich
but
challenging
areas
of
study
including
quantum
error
correcting
codes,
entanglement
purification,
and
quantum
channel
capacity.
We
then
discuss
recent
development
in
optimal
finite
block-length
communication,
a
refinement
to
the
study
of
quantum
channel
capacity.
To
approach
this
difficult
problem
we
consider
a
relaxation
of
the
optimization
that
corresponds
to
channel
codes
assisted
by
operations
that
are
non-signalling
between
the
sender
and
the
receiver,
and
that
are
PPT-preserving
(cannot
create
entanglement).
The
optimal
rate-distortion
tradeoff
can
be
formulated
as
a
semidefinite
program
and
can
be
precisely
computed.
We
discuss
applications
of
our
results
and
open
problems.
Joint work with William Matthews.