What Was The Big Bang?

in the wood-paneled chapel of the

catholic university of louvain in

belgium

a priest lights a candle and kneels

before the statue of christ for his

daily devotion

his name is georges lemaitre

and it is 1927. as he rises his eyes

wander to the towering windows that line

the chapel's walls

and to the stars twinkling in the early

evening light

he smiles in distant reflection

imagining the sequence of events that

brought that starlight

to the belgian sky but

despite his faith lumetra's beliefs were

lacking

a creator so fundamental to the catholic

doctrine

he had no need for divine intervention

when it came to the making of the

universe

no seven-day miracle instead he saw it

as a natural

consequence of natural laws and

processes

proved by mathematics and visible in the

movements of the heavens themselves

his extraordinary insight would earn him

two nobel prize nominations

for george lemaitre was more than just

a catholic priest he was also a

theoretical physicist a cosmologist

fascinated with the workings of god's

perfect universe

it was here in naivan that he began work

on a theory that would come to shape our

modern

understanding of the cosmos all based on

the remarkable observation

that space seemed to be

expanding

mathematics had laid out the history of

the universe

and now lemaitre traces it backwards in

his mind's eye

he imagines a time before humans or

indeed any living thing inhabiting the

earth

before that of course the earth must

have formed as a barren rocky ball

around the glowing sun

before that the sun ignited in a blaze

of nuclear glory crushed into being by

the irresistible force of gravity

in a vast cloud of gas and dust that gas

and dust was a consequence of many

generations of stars living and dying

before our own

igniting fusing elements and exploding

in terrific supernova

that spread their elemental waste

products across the cosmos

he imagined a time before these many

lineages of stars before the chemical

complexity that we enjoy

when only hydrogen and helium floated

inert in a lightless universe

if space is expanding now then in the

reverse chronology of lemaitre's mind it

is contracting

there would be a point in this dark

gassy cosmos before the first star

when all the matter in the universe was

compressed into a vastly smaller space

atoms would become packed so tightly

that even photons are unable to pass

through

there are no light sources here but it

doesn't matter the universe is

utterly opaque when the contracting

reversed universe crushes down even

further the atoms themselves are crushed

first into subatomic particles and then

into pure energy

in this small dense universe there is

only radiation

here even lumetra's imagination begins

to falter

the universe can become even smaller

even hotter

but what happens then

lumetra pushes the unanswerable from his

mind content in having grasped 13

billion or so years of cosmological

history

and unperturbed by the mysteries

contained within the first fraction

of a second

but the big bang theory of which lumetra

was unknowingly the first true proponent

has been the subject of debate research

and speculation

for nearly 100 years

how did the universe begin

what was the trigger for its incredible

expansion

and could our simple matter brains

ever even comprehend the real truth

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before le metre studies of the cosmos

had largely focused on our own place

within it

as well as observations to determine its

composition and extent

the 13th century philosopher sigur of

brabant was alone in venturing the

statement that the universe

was eternal with no beginning his

heretical views

outraged the theologians of the time and

earned him condemnation by the pope in

1277.

rumor has it he was murdered with a pen

a symbol of the damage his ideas had

done

since then no serious scholar had

contemplated changing history or

a beginning and so

lumetra's calculations rocked the

cosmological world

but they were not embraced by everybody

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the idea was that the universe started

its life a finite time ago

in a single huge explosion and that the

present expansion is a relic of the

violence of this explosion

this big bang idea seemed to me to be

unsatisfactory even before detailed

examination showed that it leads to

serious difficulties

one respected but controversial

astronomer fred hoyle

railed against lumetra's expanding

universe history even

coining the term big bang as an insult

for the implication of an expanding

universe is that

at some point it must have begun

expanding

and at some point the universe itself

must have begun

this hoyle confidently declared was

pseudoscience

little different from trying to justify

the existence of a creator

the only reason he said that we were so

attracted to this

novel big bang theory was because the

teachings of the book of genesis

are so ingrained into our collective

psyche

and yet lemaitre was quite happy to keep

physics and religion separate

his mathematics didn't yearn for

theological validation

and they were supported by real

observations of the real

universe made by eminent astronomer

edwin hubble

just a few years later from the mount

wilson observatory northeast of los

angeles hubble had gazed tirelessly

through the largest aperture telescope

of the time

peering at some of the dimmest parts of

the night sky

his measurements would prove

conclusively the long-held suspicion

that there were more galaxies than just

our own milky way

but they would also show something that

nobody

had expected luminous objects like stars

emit light as a result of the fusion in

their cores

the colour and characteristics of that

light depends on the temperature

and the composition of the star but it

also depends

on the star's movement just as an

emergency vehicle sounding a siren will

sound different when it's moving towards

us

or away from us so too the light from

the star will be altered

when it's moving closer or further away