Dec 13 2012
What is Time?
One of the joys of having children is the opportunity to vicariously view the world through child-like eyes. Children are generally curious, and are free from the bias of “knowledge.” I am not trying to make ignorance into a virtue – knowledge helps us to think about things on a deeper level and to see the connections that make up the tapestry of reality. But knowledge can also be a trap that constrains how we think about things.
Children may highlight this fact by innocently asking questions that are free of assumptions we didn’t know we had. Every parent has likely faced these questions. In my opinion these moments are tremendous opportunities to engage a young mind with everything that is awesome about science and intellectualism itself.
Alan Alda seems to get this. He has been parlaying his TV and movie fame to promote science communication. He is a founding member of the Center for Communicating Science at Stony Brook University. He wants scientists to explain basic concepts to the public – to children, in fact – in a way that they can understand. He gets questions from 11 year olds and then challenges scientists to explain the answer in a way that is engaging and accessible to 11 year olds, and then has 11 year old judge the answers (although referred to as “11 year olds” it seems the job of submitting questions and judging answers is open to 4-6th graders).
Last year Alda posed the question – what is flame? This is a perfect child-like question that adult may take for granted or just assume there is no specific answer to (a complacency to mystery perhaps not entirely shared by children). Many scientists submitted answers, the winner was Ben Ames whose answer was in the form of a video. Nicely done.
Alda decide to make the “Flame Challenge” a recurring thing, and this year he solicited questions from children and came up with a new challenge – what is time?
This is a perfect question, the kind of thing that most adults may assume does not have a specific answer, or if it does it’s too “sciencey” to be understandable by non-experts, or perhaps they think they know what what the answer is. Try to put the answer into words, however, and it becomes immediately obvious that this is no small challenge.
There are lots of pithy if snarky answers, such as, “time is what keeps everything from happening at once,” (which I believe was the focus of a Doctor Who episode). Such answers, however, tend to be more philosophical than scientific. A thorough scientific answer can be extremely technical and mathematical, involving relativity and thermodynamics, for example. This has the makings of a good challenge and I will be interested in seeing what real experts come up with.
My off-the cuff crack at an answer is this:
Time is a property of the universe – a measurable quantity that separates two events. It is like a stream that moves in only one direction. You are always at one point on that stream, being carried forward at a steady rate. Part of the stream is forever behind you, while the rest is in front of you. You can move more quickly or more slowly along that stream, but never backwards. Further, you cannot see in front or behind you. You can only see the boat that is your “now.” You can remember where you have been, but you cannot see or remember the future in front of you.
That is, perhaps, a simplistic analogy. I will have to think about this some more to see if I can come up with anything better. Feel free to take a crack at it in the comments as well, or even submit an official answer to the challenge.