“People like us, who believe in physics, know that the distinction between past, present and future is only a stubbornly persistent illusion.” – Albert Einstein
If I see an article title “Is the Future Already Written?” and it starts out saying that “A conscientious cosmologist rejects Einstein’s notion that time is an illusion and the future is set,” – well, I just have to read it.
Einstein and time [travel] are topics I love. That long article is in the June issue Discover magazine, but I saw it online last spring. If you’re not going to make it through the article or even this post, here is the PowerPoint bullet version: Einstein suggested that the future is just as real as the past and this cosmologist posits that the future remains a collection of possibilities until it merges into the present. That cosmologist is George Ellis and he is concerned with the flow of time itself.
My thoughts on all this started when I was in high school and read about some of Albert Einstein’s thoughts on time. Early in the 20th century, he had the view (which is still widely accepted) that the passage of time is an illusion. There is no difference between the past and the future. In simple terms, both are already determined.
That was a view I never wanted to embrace. First off, it ruins any good time travel scenarios. You go back five years and everything happens as it did before, including you doing what you did the same way with the same results. You don’t even know you traveled back in time. You could be back in time now and you wouldn’t know it. (Except for possibly a little déjà vu feeling that you had done this before? That’s my theory, not Al’s)
Ellis doesn’t like the implications of this theory either because it takes away free will and moral accountability. he is looking at this with some philosophy and ethics mixed in with his physics. He prefers that though the cosmos may create its fate, we have the ability to change our destiny.
As much as I love Einstein, I’d prefer to find confirmation for Ellis’ theory of reality: time exists and the future remains unwritten.
Ellis worked on his theory while on sabbatical at the University of Cambridge. That seems appropriate since that is where Isaac Newton wrote his Principia Mathematica and came up with his notion of time.
Newton imagined a universal clock with seconds, minutes and hours that were the same no matter where you are or how you are moving. Einstein made that seem wrong.
Einstein flipped universal time and threw in ideas about a relative view in which different people could disagree about the duration of events, and even the order in which they happened. Time is a fourth dimension.
Ellis uses this metaphor to explain the theory. Take a quick burst of successive photographs of a location, like people walking around Times Square in NYC. If you projected those photos in series (like a flipbook or on a screen like a movie), time appears to pass as we think of it. But stack the images on top of each other and it all happens at once. This second version is known as the “block universe view” where past, present and future all coexist simultaneously.
That would mean the passage of time has no meaning. All events coexist side by side.
This idea of relativity in time is hard to grasp, especially because the time differences are imperceptible at human speeds. Experiments on the International Space Station and ultra-high speed airplanes have shown that traveling faster changes the passage of time. What one person perceives as the future is what someone else saw as the past. It
Though Ellis respects Einstein’s work, he couldn’t accept the philosophical implications of a future equal with the past. “If we are just machines living out a future that has already been set, then Adolf Hitler had no choice to do other than what he did… To me, that’s an untenable view of the world that will lead to great evil because people will just stand by as evil takes place.”