Saturday, April 6, 2013

Time, time, time...

Standard Time in a Fictional Universe - what the hell is that supposed to mean?

First is the obvious: STFU.  Although rude this is often the sagest advice that a person can hear.  You need to listen and you can't do that if you don't stop running yer yap.

Second, is my utterly amateur interest in the physics of time.  Time is something like gravity - at once obvious and immediately accessible, but the deeper you delve into it, the more puzzling it becomes.

I read A Brief History of Time some years ago not long after it first came out.  More recently I've been chewing on, slowly, Time's Arrow & Archimede's Point.  In the former, one of the great minds of our era allowed himself a single equation in his book (in order to maintain accessibility of his subject to a non-specialist audience): the equation of course being e=mc2.  This is the touchstone of modern physics.  You can play with it in many ways, altering one variable and reliably deriving another, except for one.  The speed of light.  That is a constant.  Which is strange because in virtually all other contexts speed isn't constant.  But the really curious part isn't that the speed of light is constant, the curious part is time.  After all speed is nothing but distance divided by the time to travel that distance.  For our everyday life this is quite unremarkable.  But in physics in general, equations are supposed to be symmetric.  I can travel from point A to point B in a given time.  And I can travel from point B to point A.  Direction doesn't matter - except for time, at least as we perceive and experience it.  And that is the question at the heart of the latter book.

Standard physics shouldn't allow for such non-symmetric characterization (in contrast to distance which can be traversed in either direction), and Price explores the various ways physicists have tried to sweep that problem under the rug.  No one has cracked the nut.  Considering that some folks have pondered if we aren't approaching the summit of understanding the cosmos, it becomes apparent that they aren't accounting for all of what we don't know.  We once thought of space in Euclidean terms - three dimensions.  Einstein added time as a dimension, yet as far as we understand you can only traverse time in one direction (unlike the other three).  Physics doesn't like special cases - they tend to be less than satisfactory explanations, and yet that seems to be exactly what we have here.

Of course, if you try to think of time just like the other three dimensions of space, your mind gets really twisted - because our reality just doesn't allow for examples of time running in any way but from past to future. Then again, who are we to say that reality is only limited to what we can perceive - for if it is, that quickly leads us to an anthropocentric cosmos.  Imagine that, man at the center of the universe!