For thousands of years, people have wondered about the universe
Did it stretch out forever, or was there a limit?
And where did it all come from
Did the universe have a beginning, a moment of creation, as the church taught?
Or had the universe existed forever, as many philosophers believed
The debate between these two views raged for centuries
without reaching any conclusions
But while I was growing up, the debate was virtually settled
One view of the universe prevailed
The story begins with a priest, a scientist and an astronomer
We're at an altitude of just over a mile and
there's cool air coming in from the ocean, on top of...
a layer that's in Los Angles basin below
So there's a pressure lid in the atmosphere...
that keeps the warm air and the haze down below and
keeps the smooth cool air flowing over the mountain top
The images here are the crispest and sharpest in the North American Continent
In 1917, a company which usually built battleships came to this mountain in...
Los Angeles, to weld and rivet the largest and
most optically perfect telescope the world had ever seen
The observatory on top of Mount Wilson
would give us a totally new view of the cosmos
At the same time Albert Einstein unveiled his theory of general relativity,
which seemed to be predicting a universe that couldn't stand still
The models of the universe we build have to have the universe
either expanding or contracting, they can't they can't be static
But this disturbed Einstein
His assumption that the universe was static was so strong he didn't see the...
expansion or contraction of the universe as a prediction of the theory
he just thought of it as a problem that had to be overcome
by changing the theory in some way
Einstein fudged the theory,
by adding a guantity called the cosmological constant to allow
the universe to remain of constant size
But it wasn't long before his ideas were challenged by...
others, including a Catholic priest, George Lemaitre
Like Lemaitre, Father Michael Heller
believes that science and religion go hand in hand
There are two ways of making dialogue... between science and religion
One is a direct dialogue,
when theologians and scientists sit together and
they try to speak to each other and usually it's a disaster
But there is another way of making a dialogue...
between science and religion,
when for instance a priest or a religious man simply does science
Over the centuries, the scientific work...
...carried out inside the church has had a profound influence on the outside world
Father Heller has been called to Rome to attend a conference on cosmology
at the Pontifical Academy of Sciences
The Vatican established the Pontifical Academy
to have uh scientific council to the pope
I think it was an intention to engage the church into the dialogue with science
and the best way of doing this dialogue is just doing science with the Vatican
At the beginning of this century,
the burning issue at the Academy
was-how did the universe begin?
One of the first with a scientific answer was George Lemaitre
George Lemaitre was elected member... of this academy...
He studied both theology and mathematics
He was rather mathematician by training,
but he got very very interested in uh Einstein's theory of relativity
Lemaitre decided to challenge Einstein and
most of the scientific community of the day
with his own ideas of the creation
He suggested, in a vivid description almost more poetic than scientific...
that the universe did indeed have a precise moment of creation:
And that everything expanded from a very dense primeval atom
The evolution of the world...
can be compared to a display of fireworks that just has ended
Some few red, wisps ashes and smoke, standing on the well chilled cinders...
...we see the slow fading of the suns and
we try to record the vanished brilliance of the origin of the worlds
This cataclysmic beginning and expanding universe that
Lemaitre proposed are what we now accept as the Big Bang
But at the time, few scientists took the beginning of the universe seriously
Lemaitre battled on with his ideas
He even tackled Einstein face... to face, but Einstein wouldn't relent
Einstein definitely rejected the model as something unpleasant and
he told Lemaitre that his physics was not very good
Everyone assumed that the universe was static and Einstein was no exception
So probably the idea that the universe was expanding
was just simply not something he was prepared to consider
It was clear that new observations were needed to settle the theoretical debate.
The hundred inch telescope was the largest in the world when it was built in 1917,
it drew observers here the people who could use the telescopes best
to tickles out the details of how the cosmos operated
The most famous observer was an American, Edwin Hubble
His observations were destined
to end the argument between Lemaitre and Einstein
Edwin Hubble came to Mount Wilson in the early...
1920's and for his thesis he had made er a guess,
which is unlike Hubble to have done, a speculation
He thought that some of the faint wispy clouds that
you could see in the night time sky,
and these are clouds on the sky and not clouds in the earth's atmosphere,
these nebulae as they're called er had a spiral shape, have a spiral shape,
and he thought they might be external to our own galaxy
What Hubble was suggesting must have seemed extraordinary at the time
The bright clouds that could be seen
in between the stars in the night sky might actually be other galaxies,
far outside our own
They were so far away that before the hundred inch telescope
they had never appeared as more than wispy clouds
Hubble aimed the telescope at one of these clouds and
took the first ever detailed picture of it
This was not easy. To track a cloud out in space,
as the earth is turning, took great strength and endurance
To take a photograph at the same time keeping thousands of stars
in perfect registration was almost a miracle
Some of the exposures are...
thirty or forty hours, which means he did this for one night...
left the plate in came back the next night and...
re-opened the palate and began exposing again
Hubble would be standing on this platform...
all night long, guiding and guiding and guiding
Hubble found that the faint clouds in the sky were indeed...
galaxies outside our own. He developed this strikingly clear picture...
of the Andromeda spiral galaxy.
By meticulous measurements of... the brightness of individual stars
Hubble could tell how... far away the galaxy was
He found that our...
nearest neighbouring galaxy was over a million light years away.
So almost overnight he turned around our notion of the size of the universe
He increased the volume by something like a factor of a thousand million...
because now all these faint smudges of light
were not interior to our small milky way galaxy,
but were each individual galaxies holding a hundred billion stars or so
So you increased the vastness,
the size of the universe into this vast cosmos that
we know today and also made our place simultaneously,
made the universe large and own place very humble
Once Hubble had identified the galaxies he took his research a step further
By looking at the light from distant galaxies, he could tell they were moving
Hubble looked at the galaxies and as he analysed the light...
of the galaxies...
within the light that he is looking at he could tell whether
or not or how fast the galaxies are moving,
towards or away from us and he found out that
the more distant a galaxies was the faster
it was moving away from us and this is Hubbles Law
The fact that the galaxies were all moving away from us suggested that
the universe was expanding
But Hubble was cautious and didn't want to jump to conclusions
Nor did Einstein want to believe that the universe was...
expanding even though his theory said it should
But when George Lemaitre heard of...
Hubbles's discovery, he knew this was the proof he'd been waiting for
In 1931, while Einstein was visiting Hubble,
Lemaitre journeyed to California to confront them
When science and observation come together,
science often takes a great leap forward...
The basis of modern cosmology was established at this meeting
Looking back, I can recognise this as the foundations for my own work
Lemaitre had to work through Einstein's theory,
through the mathematics which are extraordinarily complex
and after presenting this to Einstein and pressing and
pressing his point and then having the evidence of Hubble there...
to top this all off Einstein was beginning to be...
convinced of the evidence for the expansion. He...
begins to realise as Lemaitre presses his point that he had made a...
great blunder, that is putting
in this cosmological constant to offset the natural expansion...
that falls out of his theories
Einstein rose at the end of the meeting and said
this is the most beautiful thing I have ever seen
From then on...
Einstein called the cosmological constant,
the 'biggest blunder' of his... life
Hubbles' work, Lemaitre and Einstein I think make up the big bang of cosmology,
that is this is the origins of modern cosmology
Hubbles work started it off first by investigating
what these nebula were and then seeing this motion,
this large scale motion of the universe the expansion,
how that linked to Einstein's theory,
showing that the universe had a beginning in time and
space some billions years ago and this is where cosmology has risen from
I was fascinated by the expansion of the universe
when I heard of it as a boy at school
But many scientists didn't like the idea
that the universe had a beginning, a moment of creation
The BBC presents...
the nature of the universe.
The speaker is Fred Hoyle,
a Cambridge mathematician and Fellow of St. John's College.
In this talk he discusses the theory of continuous creation.
Mr. Hoyle.
Perhaps like me you grew up with the notion that
the whole of the matter in the universe was created in one big...
bang at a particular time in the remote past. What I'm now...
going to tell you is that this is wrong
Fred Hoyle's attack contradicted Lemaitre,
Einstein and all the supporters of the Big Bang
Dennis Sciama now lives and teaches in Italy,
but as a young graduate in Cambridge, he remembers being swept along...
by the ideas of Hoyle and his colleagues
Like many young cosmologists Sciama preferred Hoyle's...
Steady State universe to one that started with a Big Bang.
You've got to remember that at the time
there were not many people working in cosmology;
so one or two rebellious characters could make a very big impact on the subject
Now this Big Bang idea seemed to me...
to be unsatisfactory even before details examination,
for its irrational process that...
can't be described in scientific terms
So in... 1948
they proposed the famous steady state theory which...
was a contradiction to the Big Bang; accepting the universe was expanding,
but supposing that as the galaxies move away from one another,
new matter was created between the galaxies continuously on this idea
As the universe expands, everything should spread out
It should become less densely packed
So new matter had to materialise somehow,
to keep the overall density of the universe in an everlasting steady state
If you go backwards in time
there's no increase of density and therefore no Big Bang
So you have this rather grand picture of a universe which is expanding
but which stays the same in it's overall properties for all time
I personally liked the theory
because I thought it had a grand architectural sweep
It just seemed so grand to have a universe that...
didn't change in its large scale structure ever,
and had no awkward... initial moment
But one thing the Steady State theory didn't have was an answer to
where all the matter in the universe could have formed
Supporters of the Big Bang seemed to
have the best explanation of where matte was made
To them, everything was created... in a hot Big Bang
Fred Hoyle developed this idea that we wanted to do without the hot Big Bang
The guestion was where to make... the heavy elements
Hoyle had to find places in the universe
which were hot enough for the nuclear reactions make the elements we now see
The earth and everything on it are formed from combinations of less than...
a hundred basic elements. But where did they all come from?
Geologist Chris Halls is fascinated by this guestion
To learn the geology of a place he uses traditional panning technigues...
to sift out key elements including heavy metals... like gold
The heaviest elements don't dissolve, they seem to survive anything on earth
Gold isn't subject to chemical break down in the atmosphere...
and once you have gold accumulating in a river it's likely to stay there
One suspects of course that... are so durable
must themselves have had their origin in some place
of very intense physical conditions
There is nowhere on Earth with conditions extreme enough to form the elements...
The steady state school had to prove that the Big Bang wasn't responsible...
So they looked to the stars
The great achievement,
in terms of understanding the origin of the elements, came from...
the theoretical work done by the astronomers of the steady state school
and they were able to demonstrate what was possible in terms of
putting elements together to synthesise new and heavier elements in stars
The steady state supporters argued that stars are born
when gravity starts to pull clouds of hydrogen closer together
They thought that as the pressure
builds up some of the hydrogen atoms would fuse into atoms of helium
As conditions inside the star became more intense helium atoms
would in turn fuse into the larger elements like oxygen then carbon and
so on - unitl iron was been formed
Their calculations suggested that at this point the fusion would stop
Small stars would then simply cool and
gently fade away whilst large stars would suffer a more violent death
A really massive star would collapse
in on itself creating a searing hot explosion called a supernova
This supernova triggers the fusion of all the elements heavier than iron
and blows them for billions of miles across space
They wander right across the universe as dust until they mingle with
other dust clouds where gravity starts to form new stars,
planets and eventually life
The steady state...
theorists proceeded to build up stage by stage...
a logical explanation of how...
of how these elements could originate successively,
by synthesis in the stars, but the problem was that
they had to find the fundamental fuel to start the process itself
and of course that fuel is hydrogen,
and the million dollar guestion is where did the hydrogen come from
Fred Hoyle thought that hydrogen would somehow be created continuously
throughout space. But that needed a new law of physics to make it possible
And there was far more helium...
being detected in space than could possibly have come
from the fusion of hydrogen in stars
The one obvious answer was that
the Big Bang explosion would have made both hydrogen and helium
That was the last thing that Hoyle wanted to contemplate
He did not give up easily
Fred Hoyle said that if there had been a Big Bang
there should be a trace of that event, preserved for us in the universe,
a kind of fossil radiation
And this is exactly what the Big Bang theorists went out to look for
If our universe started from a great explosion...
it would have been so intensely hot that, even today,
some faint remnant of that heat should be travelling throughout space
As a research student working for a doctorate,
I realised how significant it would be
if the radiation could still be detected, some fifteen billion years later
By now, it would have cooled to almost the lowest temperature possible,
minus two hundred and seventy three degrees centigrade
In 1964, Professor Bob Dicke,
at Princeton University thought of a way for his students
to detect the radiation from the Big Bang
One afternoon he came in and he was,
seemed particularly excited about something
He started outlining this idea about proving that there's a Big Bang
Well of course at that time...
Big Bang was very controversial...
Not everybody believed it by a long shot. The steady state...
theory was very popular
But one thing the Big Bang would predict
if there were a Big Bang is there must have been some heat radiation in it
Thought it was a long shot, a kind of a risk, such a radical idea,
but it looked like it was possible to do an experiment and check it out
And it wasn't going to take a lot of time and I didn't have anything else to do
So I decided to pitch in and help on the experimental side
David Wilkinson, then a twenty eight year...
old student, helped set up the eguipment...
to look for... evidence of the Big Bang
You have to imagine that we are embedded in this explosion
So if you're thinking of an explosion erm say a bomb going off and
you see this great fire ball, er we're actually inside that fire ball
So the radiation is coming from all directions,
we're outside looking at it and having it go by us,
we're embedded inside so we see the same thing looking all around
To search for the Big Bang radiation,
the team designed this directional horn antenna and
hauled it onto the roof of Princeton University
Back in 1965, as David Wilkinson and his colleagues
were fine tuning their eguipment events took an unexpected... turn
Bob Wilson had just started work at Bell Laboratories
Trained as a radio astronomer,
he had been head hunted by the company's research... department
They wondered if he might be able to find a new use
for their special horn shaped antenna originally...
built to receive the first satellite radio transmissions
When we were given control of the horn reflector
we saw something which we hoped not to see
That is there was more noise coming out of the horn than we expected
We expected a little bit from the earth's atmosphere,
an even smaller amount from the walls of the horn itself,
and then we thought space would be at essentially zero, so that should be it
Wherever they pointed the huge horn detector,
there was a constant annoying hiss
This radio noise didn't stop, even if the antenna was pointed at empty space
We worried as we were living on a... hill that overlooks New York city,
not the typical place that a radio astronomer would go,
so, but we have a very measuring instrument,
so we turned our horn reflector down and
looked at New York city and there was nothing unusual from there
New York city doesn't radiate at those freguencies
So, um you know, sort of one by one
we eliminated sources of excess noise that we could think of,
we still believed in physics
What came out had to come from somewhere
They wondered if the hiss wasn't coming from space at all
They looked to see if there wasn't a problem with the horn itself
The most obvious was that there was a pair of pigeons living in it
and er whenever we weren't using it, which was most of the time,
they would climb up near the cab and roost there and of course
they covered it with white pigeon droppings the same
as they do all sorts of things in cities and we knew that could well have an effect
So Bob Wilson and his team of highly gualified radio astronomers spent...
two weeks cleaning pigeon droppings from the horn
Eventually the birds were trapped and
sent by internal company mail to Whipeny, the furthest outpost of Bell Labs
But these were homing pigeons
Well a couple of days later the same pigeons back
Um, later on our technician brought in a shot gun and...
But the pigeons were innocent
The radio noise continued and the team spent...
the next year checking... their eguipment
In the spring of 1965, in desperation...
they phoned Princeton University for help...
The call was put through to Bob Dicke
We were in Bob Dicke's office and er the telephone rang
and we heard him say something about horn antenna
So then we perked right up because it was pretty clear that
he was talking to some one who had the eguipment that we were building
This turned up to be Arno Penzias and Bob Wilson from Bell Labs,
only thirty five miles away
And Bob hung up the phone and I'll never forget exactly what he said
His precise words were "Well boys we've been scooped"
They gathered their data and drove over to Bell Labs
to experience this radio hiss for themselves
When David Wilkinson saw their eguipment and
their meticulous records he knew that
his team had been beaten to the discovery of the left over radiation...
from the Big Bang
I personally was only giving it about a fifty fifty chance of working anyway,
and then when we found out yes indeed
there was the radiation coming from space that
might be coming from the Big Bang, ah that of course was very exciting
This was a paradigm shift in in cosmology research and
it would have been nice to be the first to see it
The discovery of the background radiation...
along with a number of other things that were coming up at the same time
really drove the final nail in the coffin of the steady state theory
I think it would be very hard to support the,
or to understand the source of the background radiation
in the steady state universe
It seemed this was concrete proof of the Big Bang
Lemaitre, whose primeval atom had started it all,
apparently heard of the discovery just days before he died
Much later in 1978...
Penzias and Wilson received the ultimate accolade in science
It was thirteen years or something before we received the Nobel prize... for it
The Nobel prize is given for discoveries
It's not given for being the best physicist or the best scientist,
it's given for discovering things that are interesting or useful to mankind
I still have a hard time putting myself in the same category as Einstein,
but er I do realise that this was an important discovery and
uh feel that I was very lucky to be in the right place when that happened
and I have enjoyed the results from it
The background radiation was discovered while I was finishing my doctorate
Here at last was observational evidence that could confirm my work
I had gone to Cambridge university
because I had wanted to work with Hoyle on cosmology,
and the expansion of the universe
But luckily for me, I didn't get the supervisor I wanted
When Stephen came to Cambridge...
he was hoping to work with Fred Hoyle,
but Hoyle was not taking new students at that time and
I was the only other person in the department able to supervise students
in cosmology which is what Stephen wanted to work on
So I became his supervisor and we talked together about various projects
I had made a bad start at Cambridge
I had just been diagnosed with ALS or motor neurone disease, and...
didn't know if I would live long enough to finish my doctorate
And I was having difficulty finding a problem for my thesis
To be awarded a PhD you have to...
write a thesis which contains a substantial original contribution
to knowledge and that's a very heavy reguirement and
it is very unnatural in a way because you are supposed
to produce this particular substantial original contribution
of knowledge in a given three year period...
And so you're forced a bit artificially to produce this significant result in...
a given time scale
In Stephen's particular case er his
first couple of years were a bit slow
because cosmology...
...was fallow at that time and he couldn't find a really good problem and
I couldn't find one for him
Time was running out
There was less than a year left when a suitable project was finally found
It involved developing a theory
to describe the starting conditions for the Big Bang
The inspiration was the work on stars...
done by Roger Penrose
Well Roger Penrose was by that time a good friend of mine
and he was working on a problem
which lead to a remarkable discovery of his,
which I suppose was the most important contribution to relativity
since the very early days of the theory, around 1916 or so
The issue involved not the whole universe,
that was Stephen's later contribution, but a star
Roger Penrose proved that when the biggest stars collapse
they end up crushed into a black hole
Inside which has to be an infinitely dense point called a singularity
Something as tiny and dense as the early universe must have been
Stephen said to me,
"But look he said we can adapt er Roger's argument to the whole universe
In a certain sense the whole universe is like a big star,
of course the universe is expanding,
but if in your mind you reverse the sense of time
then the universe is collapsing
It's a bit like a collapsing star, a very large star,
perhaps you can prove that in that
collapse you again must... ...achieve a singularity
So going back to the ordinary direction of time
it would mean that
the Big Bang origin of the universe would have to be singular
Should I work on that?"
So I said that sounds like a very good problem Stephen,
yes I think because that would be a very great discovery
So he went away and in his last year
he proved his first singularity theorem for the universe that
on the basis of certain very reasonable assumptions
the Big Bang had to be singular
I was awarded my PhD for showing that Einstein's General Theory of Relativity
implied that the universe must have begun with a Big Bang
It couldn't have...
collapsed, bounced, and then expanded again
From Lemaitre's primeval atom to my own work had taken only a few decades
The case for the Big Bang... was now almost complete
But there was till one major problem.
To account for the formation of galaxies,
the early universe couldn't have been completely uniform.
The radiation Penzias and Wilson had detected should somehow reflected this...
but it seemed to be the same in every direction
For the Big Bang to be...
right the radiation coming in different directions...
had to be slightly different and this had not been observed
In California, a cosmologist called George Smoot realised
there was a huge challenge beckoning...
He began a lifelong guest to find hot and...
cold temperature variations in the early...
universe-tiny imperfections that...
would mark the starting points of galaxies
For the Big Bang to be right...
we had to look out and we had to see these imperfections that
tell us how the universe formed and started expanding and
also what were going to be seeds for the large structure that we see,
that is the stars and the galaxies and the clusters of galaxies,
all of these things had to be there
When you start out you think,
well we should discover it pretty easily right away, you know,
we'll point our antenna up here and see what the temperature is and
we'll point it over in this direction and see what the temperature is,
we'll point it over and we'll compare...
and see if we can see the variations
When you start to realise that
those imperfections are going to be a part in a thousand,
a part in a hundred thousand...
it becomes a very great experimental challenge
Using directional horns like the one built
by the team from Princeton George
Smoot began a series of experiments...
His intent was to make a detailed map of the big bang radiation showing up
the cold spots where galaxies formed...
It seemed essential to get his sensitive eguipment
out of the Earth's atmosphere First they tried helium filled balloons,
but these were
very unreliable and kept getting... lost
U2 planes looked like they'd offer better control
but the pilots couldn't stay up long enough
From the beginning...
it was clear to me that if only we could get in space that
was the right way to do it
And what I really had to do was to wait for a opportunity,
wait for a chance for NASA to say all right we are looking for new ideas
for experiments for satellites that could go into space
After years of waiting NASA...
gave George his opportunity with the first ever cosmological satellite...
...called COBE
Finally in 1989 they scheduled us for a dawn launch and it was windy and...
you know, you knew too much if you were on the team,
you knew too much that it might go, it might not go,
and there was this problem and that problem
We had a problem with the guidance on the second stage test and
the test and you know there all these things to be concerned about
And then it became time for the launch and
we had only a few minutes left on the window and it was OK
You saw suddenly a second sun
which was the fire out of the rocket coming out and...
I was going what's the matter, I don't hear any sound,
I don't hear any sound and
then I realised you know light goes faster than sound and
then suddenly your chest is shaking you know
it's like your being hit at a rock concert,
your standing at the speakers of a rock concert just being vibrated like this
and this thing lifts off really majestically and goes up and
it's just spectacular thing you know and you're going you know,
everything is crossed, and you're going please make it up,
please make it up, right
The COBE satellite was a fantastic success. The results were unprecedented
At the end of that first day...
we made a map that covered half the sky and it was as good a map
as we'd ever had before, but it was way less than we eventually ended up
It took a whole years worth of data almost three million,
three hundred million observations to be summed together
before we got a map that started to show some interesting structure
At last a picture of the universe as it was fifteen billion years ago
The hot fireball has cooled down and structure is beginning to form
The pink and blue patches represent minute temperature differences;
the cooler blue areas are where matter is beginning to cluster to form galaxies
COBE really puts the big bang on a firm footing, not...
...only you know the big bang is right
but now you have some idea about how structure is going to form,
but also you can learn about how the universe itself was created
COBE finally clinched the... of how the universe formed.
The project is now at an end...
and the Smithsonian Institute is setting up a museum...
display to commemorate its historic achievement
COBE had traced the earliest structures ever seen in the universe
If you're religious it's...
like you know you're you're you're seeing God or you're seeing the handwriting of...
God when he wrote out how he was going to make the universe
It's like getting the ten commandments in front of you and
and being able to read, right except instead of the commandments these are,
here's how the universe is put together, right
Just you know, read between the lines and you'll know,
you'll know the recipe for making the universe
In this technological cathedral
they are building a successor to the COBE satellite
Whatever it's destined to reveal it is unlikely to overturn the evidence
in favour of the Big Bang offered by COBE. Lemaitre's primeval atom
and the discovery of the Big Bang provided the Church with...
a moment of creation
But it also gave science it's most convincing explanation of the cosmos
In 1975... I was awarded a medal by the Pope
for my part in proving the Big Bang Theory
I went back to the Vatican in 1981, for a...
conference on cosmology this time under a different Pope
He told us that it was fine to study the universe after the Big Bang,
but that we should not inguire into the Big Bang itself,
because that was the moment of creation...
and the work of God
If science and religion were now at one,
perhaps they were still not guite seeing eye to eye