Mr Tyner told us a week ago that we would have a lecture today by Andy Fletcher that would change our lives. I was looking forward to it all this past week. He told us we would probably write a whole page about it for our TOK weekly reflections and I’m now going to find out if this is true.
Andy Fletcher is a great captivating and funny man who wasn’t afraid to start off with a joke, that I think not many people including me got. He said this presentation could go on for a day but that he was glad he could give us an hour and a half, showing his interest and passion for this subject.
He started by showing us a picture of the star-forming Eagle Nebula 22 light-years away from here. “What can we deduce from this?” he asked us. The answer was stars form in clouds.
This is what he told us: how do we know science is true?
– Science comes from facts
– Facts come from evidence
– Evidence comes from observation, experiment, assumption and interpretation.
– Time passes, technology improves and so does evidence.
-Evidence is limited by our abilities to observe and experiment, by our assumptions and interpretations.
One of our assumptions, for example, is that the law of physics work everywhere. We’ve only been able to test it on the moon. So we can’t prove this is right. The moon is extremely close to the earth relatively to the size of the universe.
Today, we might think there are many things that are true, that are facts, that may not be. Is evidence the same as proof? Are facts really facts? We used to think the earth was flat, the universe was geocentric, the earth/universe was young (about 6,000 years old)… Religion unnecessarily used to say that the earth was at the centre of the universe. When this was proved wrong, religion lost all its credibility about the rest it said.
“Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, none absolutely certain.”
– Richard Feynman
And then it got really interesting. This captivated the attention of the whole room. Right when some were starting to lose interest and concentration, he started giving examples of how time was affected by gravity. The closer you are to the center of the earth, the less you are affected by time. This is amazing! At first I thought he was joking, but then realized he was serious. He said in the future, when we will be able to travel much farther and faster, astronauts could leave for a few seconds, come back to earth and be 20 years younger than they would have been if they had remained on earth! I found this hard to believe and decided to look more into this. And indeed this is true. It’s called time dilation. You can check out the wikipedia page to learn more about it, which I did. http://en.wikipedia.org/wiki/Time_dilation This is just mind-blowing! Who knows, maybe time machines do exist after all!