This week I found myself in a conversation concerning the possibility of life elsewhere in our galaxy, so reference was made to the Fermi Paradox (http://en.wikipedia.org/wiki/Fermi_paradox).
The conversation then rapidly moved onto detecting other forms of life and how would we, with our technology, be able to detect signs of a far superior civilisation and if their technologies were so different to ours, how would they recognise our signature?
All good questions.
My answer was that a far superior civilisation would still have needed to use technologies and methods similar to ours at some point in its history and so would be able to recognise the difference between natural and manufactured elements.
“What if the maths they use is different? or what if their planet has different natural elements that we don’t even know of?”
My answer was that just because the symbols and language they use to describe maths is different, the calculations to determine things like the effects of gravity or the methods used to determine the elements in the atmosphere of a distant planet remain the same. The distance from here to there is the same despite you measuring it in kilometres and me measuring it in miles.
The elements question is interesting. However, despite not having been to every planet in the galaxy, we can say with very high confidence that we can describe all the elements that are found naturally in planets because we’ve been experimenting on the natural elements for a very long time. Scientists know so much about the natural elements that they can describe which ones work well together and which ones don’t, which ones are stable and which ones aren’t and a whole host of other characteristics.
Scientists also know enough about how planets form that a sole planet in a distant solar system is not likely to be the only place an unknown elements resides. If there was such an element, we would expect it to exist in other objects that were formed from the same source material as the planet, the source of the material would possibly be from a supernova and so the element would be spread about locally (locally being a relative term, the distance spread would actually be large). Also, because we now have good knowledge of what is formed in a supernova we’d not expect a supernova to generate an element that we’ve not seen yet. So another equally dramatic but poorly understood event would be required. Dramatic events like that would not go unnoticed.
It was at this point than the charge came.
“Science is so arrogant that it thinks it can say things like that about objects it hasn’t even seen. How can it possibly say it’s not possible for a new element to exist on another planet on the other side of the galaxy?”
“Did you listen to what I said?”
“Yes, and it’s still arrogant to say you know that.”
“We know that because for decades and centuries scientists have been experimenting with these things and the confidence is high. You can’t just think up a hypothetical element and then accuse science of being arrogant for saying it doesn’t exist.”
So the conversation ended and while I did my best to explain why science knows things and can be confident about other things, people will still mistake this for arrogance and invent impossible scenarios to try and demonstrate that.
What was odd about the conversation is I was once on the other side and I recognised so much about my former self that I really don’t miss. I hope I made a good impression on my conversation partners.
For the interested, one was a Christian and the other an atheist. Yet they both shared the same view that science can be arrogant. A view that, in this specific case, can be shattered with good knowledge that isn’t difficult to find.
I had a bigger chuckle yesterday as I was thinking up this blog post because this appeared in my feed: http://pseudoastro.wordpress.com/2014/12/05/how-to-not-understand-science-and-use-that-to-say-science-is-wrong/
If you have even a passing interest in things astronomy and don’t already follow Stuart’s blog and podcast, I highly recommend that you start.