we've found two correlations one is a
correlation that more massive galaxies
contain more massive black holes and the
other is a correlation that galaxies in
which the stars are moving faster
contained bigger black holes
what the results are telling us both of
these correlations are telling us are
screaming something important others
they're telling us that there's a very
close correlation very close connection
between the time in the history of the
black hole and the black hole got most
of its mass and it's a process by which
the galaxies form and we have suspected
that there is such a correlation for a
long time but it gets a lot more
ironclad when the correlations that we
see get as good as they are now
for the past thirty years many people
have been trying to understand quasars
and they've built up a very complicated
theoretical picture about what quasars
are and on the other hand there have
been other people who have been trying
to understand galaxy formation and
they've picked built up several pictures
actually of how galaxies might form but
the quasar in the galaxy formation
pictures weren't very closely connected
what our work has helped to do is cement
the connection between the quasar and
galaxy formation pictures and in doing
so reduced the number of possibilities
about galaxy formation that people are
thinking about
one of the missions of the hubble space
telescope since the very beginning I
think was always thought to be the
search for supermassive black holes
because what you need to do is be able
to see very close to galaxy centers and
getting outside the atmosphere is
central to being able to do that so this
problem has always been on our mind and
similarly the properties of the
spectrograph were designed in part to
make it possible to do this kind of a
search so both the Hubble Space
Telescope and this spectrograph
specifically are addressing a lot of
problems but one of the central ones has
always been the black hole search
this spectrum shows the other parts of
the galaxy well in the inner parts of
fried
and the problem is that the surface
brightness is bearing a lot galaxy
that's bright so I can also display this
so that you can see the middle
and then you can begin to see that
there's a zigzag in the spectral lines
that's the signature of the black hole
but you can't see it very well so if I
take the surface brightness gradient and
divide it out then I get this image now
the surface brightness doesn't vary
anymore because I've taken it out and
all you see is the spectral lines and if
you look at this you see there's a
collection of very narrow lines here in
here there night-sky absorption lines
water in the Earth's atmosphere these
are the lines that belong to the galaxy
and you can see that these lines have a
very big zigzagging in them and that's
the Doppler shift the color at which the
atoms in the star surfaces are absorbing
light which is that color that color in
that color but not these that color is
being shifted it because the stars are
moving so on one side it's shifted
toward the red and the other side is
shifted toward the blue that's because
as you look at this galaxy this side is
spinning away from you and the other
side is spin towards so on one side the
lights blue shifted and I'm the only
side of the center the light red shifted
like that and that's the signature of my
home near the black hole the Stars have
to move very fast because there's all
this extra mass support and then I can
take this spectrum and run it through a
reduction program that calculates
velocities right because all here here
you see qualitatively what's going on
but if I run it through the program that
car
velocities quantitative data
this shows a quantitative version of
this brightness as a function of color
so it's a cut through this and this is a
cut bad at large Radeon and these three
spectral lines are these three spectral
lines and you can see they're not as
narrow as the night-sky lines but fairly
narrow that's because the stars aren't
moving very fast here
this is a standard stuff so this is one
single stock and you can see how much
narrower the lines are the fact that the
lines were broad and the other one means
the stars are moving a little bit this
is how the rotation velocity depends on
position so rotation here rotation here
rotation here and then as you get into
the zigzag there's the big zigzag and
rotation velocity and I can expand this
up so you see it better this is just the
very center you can see how very fast
the center spinning on one side the
Stars are going away from us at 150
kilometres per second on the other side
the Stars are coming toward us at 150
kilometres per second because the centre
spinning and at the very center of
course the Stars are rotating and if you
look that it gets out of that clary
you