The Search for Lost Time

Time is God's way of keeping everything from happening at once
...........sometimes attributed to Einstein or John Wheeler.

The times they are a-changing
......Bob Dylan

Sean Carroll takes up the question of timelessness in physics, quoting Fotini Markopolou:

There are two kinds of people in quantum gravity. Those who think that timelessness is the most beautiful and deepest insight in general relativity, if not modern science, and those who simply cannot comprehend what timelessness can mean and see evidence for time in everything in nature. What sets this split of opinions apart form any other disagreement in science is that almost no one ever changes their mind…

Which unchanging character is certainly plausible if one doesn't believe in time anyway. Neither Sean nor Fotini has much sympathy for the anti-time warriors (whose original ranks included Einstein), though she would like to do away with geometry, gravity, and space instead.

As Sean points out, however, those in the timeless crowd still seem to be able to meet deadlines and read plane schedules. Time might be dispensable in physics but it's surely not in everyday life. One of our most fundamental applications of time is our sense that decisions still wait to be made about the future and still affect its nature. After all, if time doesn't exist, why bother to get out of the way of a speeding car? Or why bother to plan a physics experiment, if its results are already and always determined.

Our sense of time is thus a fundamental survival skill as well as completely necessary for doing physics or any other science. My feeling is that if time fails to appear in what you consider the fundamental equations of physics, so much the worse for the equations. The first duty of a theory of physics is to explain our observations of the world. We wouldn't tolerate physics equations which decided that gravity was unnecessary (sorry Fotini!) and we shouldn't tolerate equations that don't include time, not, at least, until one has an alternate theory which explains the same observations. The fact, for example, that general relativity is essentially timeless is a flaw - proof, probably, that the theory isn't quite right.

The fundamental question is whether there is any physical significance to a statement like "nature is timeless" or "time is an illusion." How would one go about planning an experiment that tested such a statement? Which invites the question of what "plan" (or any almost any other verb) means in a timeless world.

Whether we believe in time or not, however, we will continue to plan, decide, and otherwise act as though it did. And those who fail to do so are likely to quickly come to the end of their own worldlines.

Comments

Post a Comment

Popular posts from this blog

Anti-Libertarian: re-post

The most pointed critique of social security and liberalism in general is the libertarian critique. The problem with libertarians, for a liberal, is that we have too much in common. We both believe in individual rights, tolerance of individual differences, and dislike government prescription of religion. The basic difference, it seems to me, is the different answers we give to Cain's (with thanks to the Captain - my original version had the corpse asking the question!) famous question: "Am I my brother's keeper?" That's not really my basic bitch against the libertarians though. My real complaint is the same as my complaint against most religion - its premise is a fraud. For those who can't stand to wait for the punchline, I believe that trying to implement libertarian principles leads to tyranny or social disintegration. Demonstrating that takes some historical (and pre-historical) context. For all but the last 15,000 or so of the 100,000 years the human spec
Read more

Uneasy Lies The Head

Uneasy lies the head that wears a crown ........... Shakespeare Henry IV, Part II. So it is with us and our slightly distant primate cousins , so it seems. A 9-year study of wild baboons in Kenya by Princeton University and the Institute of Primate Research may turn conventional assumptions of alphas males upside down. The study found that alpha males have high testosterone levels, which allows them to dominate other baboons, get access to more food, and attract better mates. This is expected. Surprisingly, though, the alpha males also have high levels of stress hormone glucocorticoid, which scientists measured from their feces samples. In fact, the stress of alpha baboons was on par with low-ranking baboons. The convention wisdom is that access to food and females provides life security and thus less stress for dominant males. Conversely, weak males who are constantly threatened by starvation and physical violence from stronger males are thought to be more stressed. The st
Read more

We Call it Soccer

The US played its best, and maybe only good game of World Cup, but lost thanks to brilliant goalkeeping by the Swedish keeper and the bizarre method soccer uses to settle ties when three US stars could not put the ball on frame from the 12 yard spot.  At the end it came down to a blocked shot that spun in by maybe a couple of centimeters. Well, that's football - too much like life.   Which brings me to a modest proposal.  Replace the thirty minute overtimes with as many 7-player 15 minute periods as needed to settle it.  Scoring should be much easier with fewer players.
Read more