Approaching the Unknown
[Music]
do you see
the pale blue dot on this image
that’s earth that’s us that’s all we add
to space
a single fleck of dust orbiting a single
star
and a single galaxy in the universe
filled with billions upon billions of
these
but if space is so vast so big
how do we even start to make sense of it
all how do
astronomers make sense of space
i want to introduce you to four concepts
that astronomers use to understand the
universe
four ways to solve mysteries i want to
show you how
these concepts help in in understanding
the universe but also how they can help
you
in your lives so how do these methods
help
astronomers well for the past four years
i’ve been working on one of the greatest
mysteries in modern day astronomy
a mystery which started back in 2007
when something more powerful than we had
ever seen before
fried our telescope in a single flash of
light
we had no idea where it was from and we
had no idea
what to create it at we used this flash
of light
which we called a fast radio burst
or an frb to
test our ideas now
how do these ideas also apply to your
life
wow to that end i want to introduce a
metaphor of the unknown something like
a monster under the bed
at some point in all of our lives we
have been afraid of
such an unknown after all
that monster that could be anything
i mean it could be big could be vast
could be streaming out
under the bed so how would an astronomer
approach
such a monster just as they would
when looking up into the vastness of
space
well that brings us to the very first
concept
always try to think of the connections
to
things you do know everything always has
those connections everything
has to interact with something you do
know
this is always the case take for
instance
a monster under the bed now
we may not know what the monster looks
like
but we know what a bed looks like
regardless of
the shape or the form the monster takes
under the beard
we know that it has to fit under the bed
now that connection the connection
between
a beard and a monster is something we
call
a boundary condition boundary condition
because it is on the boundary of
something we do know the beard
and something we don’t know the monster
now that flash of light which we saw in
2007
that also contained a boundary condition
it was just
a couple of milliseconds long faster
than the blink of an eye
we could calculate that that had come
from something which was
just 300 kilometers across
now 300 kilometers is pretty small for
space
something no larger than the netherlands
was creating more light
in a millisecond than the sun does
in a century here the duration of the
burst formed a boundary condition on the
remarkably
small size now
identifying such boundary conditions
is essential in astronomy
so how would an astronomer go about
finding more of these boundary
conditions more of these beards
well that leads us to the second concept
think about one thing at a time
let’s go back to our monster under the
bed now it might be
tempting to think about the size and the
shape and the smell or the
texture of the monster under the bed all
at the same time
but why do that all at the same time
instead it’s easier to think about one
thing
at a time for instance
does the monster ever move around
and if you think carefully it doesn’t
even if you listen very carefully you
don’t hear it
running around under the bed so you can
start to narrow down your possibilities
it’s probably either standing still
under your beard or
it’s very sneaky now you can use that
same concept
with a flash which we saw in 2007
here too we could think about the size
and shape and the color and the
temperature of the object
emitting that flash all at the same time
but no instead we want to think about
one
aspect at a time for instance
does it ever change over time now
this flash the flash was emitted and
then suddenly there was nothing
that’s not like the sun which is always
shining
so even just that simple step shows us
that whatever it is it’s not like the
sun it has to be something else
something more extreme now
these two concepts finding your boundary
conditions and
thinking about one aspect at a time they
help narrow down your possibilities they
limit your options
but you can do even better even better
using a third concept
keep your idea simple
let’s go back to our monster under the
bed now
here perhaps it’s a yeti like monster
lying flat on the beard
perhaps it’s a picture shaped monster
fitting just in between
any of the boxes you have under your bed
but why go for something so complicated
instead go with a simple idea
start for instance by assuming that it’s
very simple shape
like a soccer ball rather than expecting
it to have
44 tentacles try expecting none
wherever possible run with the simplest
idea
that flash which we had seen we would
try and find its origin what had created
it
now we knew that it had to be very fast
in doing so and we also knew that it had
to be
very bright now if our idea
had to be simple what options did that
leave us
fast bright and simple
well why not an explosion
we know of stars in space that explode
at the end of their lifetimes
perhaps there was something like that
that leads
us to the fourth final and most
important concept in approaching the
unknown
test your ideas take our monster under
the bed
we may have formed an image or an idea
in our minds of what the monster may
look like
but what good is it if we never try to
find the monster one approach would be
to
simply actually look under your bed
and perhaps you don’t have to find the
monster that’s okay
then you can adapt your idea perhaps
it’s only there while you’re sleeping
and then you can test that idea and you
can adapt your idea and test your idea
and on and on
and on and every time you get a step
closer to the truth
that flash which we saw in 2007 wasn’t
the first one
by now in 2020 we’ve seen hundreds of
these flashes of light
coming from all across the sky
remember our idea that some sort of an
explosion
might have been behind these flashes oh
time tested that idea for us at some
point
we saw multiple flashes of light from
all across the sky
and one of them had multiple flashes
from the same spot
now generally explosions only happen
once they explode and then there’s
nothing left to explode
so that told us that explosions probably
weren’t the idea
the right way to go we had to adapt we
had to change our idea
reality isn’t going to change to what
you think it is
it is always us you have to adapt and so
we did
earlier just this week we found evidence
that these flashes might emerge from
objects that
flare these flares then collide with
each other creating these
brilliant beautiful flashes of light
that we then see
on earth but our understanding will
change
that is the nature of science there will
always be more mysteries
but it is what we learn along the way
that changes
how we see the universe all
by using four concepts finding your
boundary conditions
thinking about one aspect at a time
keeping your idea simple and testing
your idea
these four concepts allow astronomers to
explore the vastness of space
they allowed us to approach the monster
under our bed
and they allow you to explore every kind
of unknown
in your life so when you next encounter
something
that you don’t know don’t let its size
or its complexity scare you
instead approach it
and say hello thank you