Why Is The Universe Perfect?

[Music]

richard feynman was worried

about a number

in the 1940s he had worked out how

electrons interact with light an insight

that earned him a nobel prize but a

particular number bothered him

all good theoretical physicists put this

number up on their wall and worry about

it

immediately you would like to know where

this number comes from

nobody knows it's one of the greatest

damn mysteries of physics a magic number

that comes to us with no understanding

by man

that number

was the fine structure constant

it sits at the heart of feynman's

theoretical success quantum

electrodynamics it is a number that

tells us about the strength of

electromagnetism and has a value close

to one divided by 137

feynman's theory cannot calculate this

number and his equations are impotent

until you measure its value in an

experiment

and scientists today are still asking

the same question that feynman did 70

years

ago where does

this number

come from

and it is not alone

our physical theories are awash with

constants of nature

they dictate how the fundamental pieces

of the universe operate how electrons

repel electrons and how gravity draws

matter together some of these constants

are familiar such as the speed of light

and planks constant others such as quark

mixing and yukawa couplings are found

within the complicated mathematics of

physics on the edge and without

measuring and calibrating these numbers

all physical theories would be useless

the constants of nature are clearly

central to all physics

but they appear to play a pivotal role

in an even bigger question

how

are we

here to understand this we are going to

have to take a journey

into ourselves

peeling apart a human we find a complex

mix of organs and fluids as we appear

closer we find that these are built from

a diverse range of individual cells each

interacting to perform the task of the

liver or muscle or the brain closer

still each cell is revealed to be a sea

of complexity a wealth of smaller

elements ribosomes and chromosomes

cytoplasm and mitochondria each playing

a part in the running of the cell the

pieces of these cells are composed of

molecules proteins and lipids dna and

rna each level so far has uncovered a

wealth of complexity but as we go

further simplicity appears molecules are

built from atoms with each complex

arrangement enabling the complex

interactions with others but chemistry

tells us that there are only 92 natural

elements from hydrogen to uranium

so only 92 different kinds of atoms are

available

entering the world of the subatomic and

even simpler picture is uncovered with

each atom being a mix of three different

particles protons and neutrons within

the atomic nucleus with orbiting

electrons and the protons and neutrons

are also composed of smaller particles

known as up and down quarks here at this

fundamental level we find that matter

people trees planets and stars are

nothing but different arrangements of

these quarks and electrons

of course these pieces need glue to hold

them together and for fundamental

particles this is provided by the

fundamental forces atomic nuclei are

held together by the strong force atoms

hold on to electrons with the

electromagnetic force gravity draws

matter together to form planets and

stars in the mix also is the weak force

which can influence the stability of

atoms

simply put we are built from the ground

up

our physical existence in this universe

is nothing more than the manifestation

of a huge number of interactions of its

fundamental pieces

and all these interactions are dictated

by the values

of the constants

of nature

but where did these values come from

does the cosmos

have to be this way

and was the fundamental universe primed

from the big bang to now to necessarily

produce the complexity that appears to

be essential

for life

these seem like strange questions

we have only this universe with the

values of these constants of nature

revealed to us by experiment

they appear to be written into the very

fabric of existence

but science is built on what-if games

pondering how things would change if the

situation were different

what if questions have the potential to

answer not only the question of how we

are here

but maybe

even why

[Music]

this video is sponsored by magellan tv

the documentary streaming service

question at the speed of light how long

would it take to travel to andromeda our

nearest galaxy a 500 years b 2.5 million

years or c

25 million years

that's right it's 2.5 million years and

infinite energy

probably not worth it

and so our recommendation this week is

the documentary faster than light the

dream of interstellar flight a

fascinating exploration of the different

possibilities when it comes to venturing

towards our nearest neighbours

antimatter drives warp speed laser

engines explore the wild edges of

theoretical science magellan are a sort

of netflix for documentaries with more

than 3 000 documentaries to choose from

on a wide range of topics

so click on the link in the description

for an exclusive month-long free trial

for history of the universe viewers

thanks

standing here on earth it is easy to

think that the universe was made for us

it feels like we are at the center of

everything with the sun and the stars

whirling around us

indeed as human civilization began our

cosmic location was written into our

developing religions

to the ancient babylonians our flat

circular earth was surrounded by an

infinite ocean of chaos

the greeks and romans saw the patterns

in the stars as a storyboard of myths

and legends of gods and monsters

in china the universe was arranged in

rotating shells centered on the earth

and containing the stars and planets

but science has since stripped away this

illusion in 1543 the astronomer and

mathematician nicolaus copernicus

displaced the earth placing the sun at

the center of everything the dethroned

earth orbited this fiery heart of the

universe

the coming of the 20th century saw us

demoted further as massive telescopes

peered into the heavens it became clear

that the sun is but one of billions of

other stars within our milky way galaxy

and now we know the milky way is one of

potentially trillions of galaxies in the

observable universe

whilst hubble charted the cosmos

measuring immense distances between the

galaxies einstein friedman and lametra

found it to be evolving and expanding

born in an event 14 billion years ago we

now call the big bang