Thursday, October 27, 2016 2:00 pm
-
2:00 pm
EDT (GMT -04:00)
Title: A Looped 4-Vertex Path Never Has Perfect State Transfer
Speaker: | Christopher van Bommel |
Affiliation: | University of Waterloo |
Room: | MC 6486 |
Abstract:
A
continuous
quantum
walk
on
a
graph
is
determined
by
a
unitary
matrix
defined
as
a
function
of
the
adjacency
matrix
of
the
graph.
A
graph
has
perfect
state
transfer
between
two
vertices
if
there
is
a
time
at
which
the
corresponding
entry
in
the
unitary
matrix
has
norm
1.
It
is
known
that
perfect
state
transfer
does
not
occur
between
the
end-vertices
of
any
path
of
length
at
least
4,
however,
there
is
a
claim
based
on
numerical
evidence
that
it
can
be
achieved
for
any
length
path
by
adding
loops
of
an
appropriate
weight
to
the
end-vertices.
We
will
demonstrate
that
the
claim
is
false
for
a
4-vertex
path.