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The Past is the Past, or You Gotta Believe

Science fiction plots took a serious hit yesterday when two professors, using quantum mechanics theory, moved a step closer to showing that even if we could figure a way to travel through time – we couldn’t change the past. While…
June 21, 2005

Science fiction plots took a serious hit yesterday when two professors, using quantum mechanics theory, moved a step closer to showing that even if we could figure a way to travel through time – we couldn’t change the past.

While I was fascinated by the article (and implications), the idea of the discovery got me thinking about the role of science in our current world.

First, though, let’s get to the discovery. This from the story on RedNova:

‘It would appear that things were happening which you could not control, which just do not allow you to alter the past in a way that would be inconsistent with the future you came from.’ Professor Greenberger added:

‘Once something has happened, the effect is that it kills the other possibilities because there is this feedback into the past. The past is determined. The future is still undetermined, which is consistent with our ideas of free will. It is a nice philosophical solution.’ Their findings solve the conundrum which has puzzled scientists for years: if a time traveller can change the past, could he jeopardise his own survival?

In The Fabric of the Cosmos, Brian Greene wrote about this conundrum and the String Theory problem created by an interchangable past and future. (Since the equations appeared to work both backwards and forwards, it suggested that all of time was fluid – and not an arrow, which is how we perceive it.)

And that takes me to the end of my understanding about String Theory.

However, it does raise an interesting question about the scientific process, one which Greene addresses in light of trying to marry quantum equations with real-life perceptions. What takes precedent: Our perception of how we believe reality works? Or the math that may redefine our perceptions in ways that we literally cannot comprehend on a macro level?

I’ve always been comfortable with the idea that the ‘answers’ to these questions would be beyond our perception. It makes sense. I wouldn’t expect to ‘get’ everything. The universe is too large. But those answers do leave themselves open to very easy attacks, since the obvious response is, ‘But I don’t see it.’

And that is what frightens me because we see this assault on science all around us, from the creationist arguments in Kansas to the White House’s denials about global warming.

It’s as if we, as a people, believe we have a divine right to perceive all of the answers before our very eyes (as if faith in science is somehow less important than faith in religion). And, absent any visual proof, disbelievers in science feel emboldened to cast aside new findings because they can’t be ‘seen’ (or more likely, because they don’t fit into a political framework for one’s beliefs).

I wouldn’t argue that science is the end-all, beat-all for answers. Much of what I read about high-end mathematics and physics borders on the religious. In many respects, I think the two are fused together in at least one fundamental area: the search for who we are.

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Illustration by Rose WongIllustration by Rose Wong

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