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