The metal in my gold wedding ring was made in a blinding flash of light billions of years ago in a supernova – an exploding star. That’s the line that pulled me into a TV program where Stephen Hawking explains his theory of everything. Having read his latest book I was hungry for more! Plus, hearing an idea in different ways is really helpful in understanding it better. I’ve read it, now I’m going to hear and see it. I wonder if there is a song about string theory or even a musical!
Anyway, back to the source of my ring. In the early universe hydrogen was pulled together under gravity and in the burning furnace of the star other elements like carbon, oxygen and sodium were made. The process stops at iron as making heavier elements requires rather than releases energy. As more of the matter turns to iron the star compresses in on itself, which makes it hotter and hotter (10 times our own sun) and eventually it explodes in a supernova. The shock wave of the explosion causes heavy elements like gold to be formed. All these newly formed particles explode out into the universe creating a beautiful nebula. Gravity then begins to pull it all back together to form new stars and planets. Apparently our sun sent out a huge blast of solar wind which cleared the dust and debris away to the outer edge of our solar system.
Some stars are big enough to make a black hole when they collapse. Although they explode the central core continues to crush in on itself even pulling in light. If you crushed the earth to the size of a pea it would be dense enough to form its own black hole. These things (black holes not peas) are really useful to have around. There is one in the centre of each galaxy holding the swirling mass of stars together.
Hawkins also talks about life:
“Life is one of the strangest phenomena known. In my opinion it shows that the universe is capable of almost anything. Yet is amazes me that we can know so much about how the universe began many millions of years ago but we have yet to discover how life itself began. The most likely explanation is probably that we are an accident. Just by chance some molecules bumped into each other at random until finally one formed that could copy itself.”
I wonder what makes it the most likely explanation (I won’t comment on the ‘molecules bumping into each other’ as I’m sure he is simplifying it for us).
Then began the slow process of evolution that lead to all the extraordinary diversity of life on earth. Life seems to be simply what emerges given the right conditions and enough time. I think that life is probably very common throughout the universe… “
Based on what I wonder? We have one example of life forming. A sample of one tell us nothing about the chances of it happening.
“One thing sometimes troubles people when they hear this story. How could such an astonishing chain of events which resulted in us be an accident. Perhaps Science has revealed that there is some authority at work setting the laws of nature such that we can exist. On the face of it life does seem to be too unlikely to be just a coincidence. The earth is the right distance from the sun…. the sun lasts long enough for life to get going….the solar system is littered with all the right elements for life….these elements are only possible because of older stars that burnt out. These older stars only existed because of a tiny unevenness in the early primordial gas that was itself produced by a 1 in a billion imbalance in the sea of particles that came from the big bang. So is there a grand designer who lined up all this good fortune? In my opinion. Not necessarily.
What if there were other universes not a lucky as our own, each coming into existence from its own big bang and hand having different laws. Some without gravity or without hydrogen that fused and so no stars could form…In these dead dark universes there can be nobody to wonder how lucky they are to exist. So perhaps we should not be too surprised to find ourselves in a perfect universe, on a perfect planet orbiting a perfect sun because that’s the only place that life can exist.”
But that only pushes the issue further back doesn’t it? Why is there something that produces multiple universes? The proposed multi-universe system seems set up to produce life. Where did that come from?
He goes on to talk about the possible demise of our planet and eventually the universe.
“Physicists can also tell us what mankind will face in the future and even the fate of the universe itself.”
In 2020 a large rock will pass so near to the earth that it might pass beneath the satellites that orbit our planet and broadcast sky TV to us. It should miss us but there are other really large rocks out there, some the size of Manhattan! In fact one hits the earth every 100 million years or so. Queue some cool CGI sequences. The last one probably wiped out the dinosaurs. Maybe it’s us next time! Or maybe well blow ourselves up sooner with a nuclear bomb. Or maybe a gamma ray bust from a nearby sun will strip away our protective atmosphere in dazzling light show that will put the northern lights in the shade. His advice is basically that we have got to get out of here as quickly as possible!
“in my opinion the launch of Apollo 11 is probably the most important moment in human history. It was a turning point for the universe too. Life in the form of us escaped its home plant and stepped onto another surface. The astronauts footprints stand persevered to this day, a testament to the beginning of what I think could be the next chapter in the story of the cosmos; the spread of life to other parts of the universe”.
The next stepping stone he says is Mars. But sooner or later our solar system will cease to exist when the sun heats up and expands. By then we would have to have made it over 20 light years away to somewhere like “Gliese 581 d”, a planet that might support life. That will be tricky and expensive and the journey would take a lifetime. We would need to extend our lives. Genetic engineering he says will help us do this as well as increase our abilities. In 3 billions years our galaxy will merge with another neighboring galaxy which would probably make it hard for anyone who was around then. Then there might be a big crunch when the universe goes back to a tinny point (our universe has at least 30 billion years left so don’t panic) but Hawking’s puts his money on a big Chill when the universe gets ever bigger and colder.
And that’s the end of the program. I think it was more based on his first book so didn’t talk much about string theory. Oh well. Interesting anyway. I am still amazed as I look at my ring to think that it came out of a supernova.
A corollary of all this is that we are made of star dust. That might sound special but actually it gives us no value what so ever. A worm is made of star dust too and when you think about it being made of something does not impute intrinsic value. People put a price on gold. It’s only worth something to someone. Value is assigned by people, it is not a product of particles. The bible tells me we were fashioned out of dust by God to be in his image and in relationship with him. Our value and purpose and reason for living comes from our creator.