'If time travel is possible then there is no such thing as time'

That sums up the book I finished last night, "A World Without Time," by Palle Yourgrau.

The ostensible subject of the book is the deep friendship between Kurt Gödel and Albert Einstein in Princeton, New Jersey.

Both were early members of Princeton's Institute for Advanced Studies, where the greatest minds in the world were paid to be themselves and simply think about things.

No teaching, no publication requirements, just do what you like each day, forever.

Sounds a lot like bookofjoe, actually, apart from the "greatest minds in the world" part.

There are those who might argue that producing eight posts a day seven days a week is somewhat akin to a "publishing requirement" but I would counter that producing bookofjoe is who and what I am and so not a requirement at all, and certainly not onerous once considered in that light.

Here it is worth noting a definition of work coined by a University of Virginia psychiatry professor years ago, still the best one I've ever come across:

"Work is what you're doing when you'd rather be doing something else."

So if this is my favorite thing to do and what I prefer above everything else then it could hardly be termed "work" and doing it regularly likewise is in no way meeting a "requirement." But I digress.

Yourgrau believes that Gödel's 1949 paper proving that there are possible worlds described by Einstein's theory of relativity in which time — as we ordinarily understand it — does not exist, upended the world of philosophy.

Gödel went further: if time is absent from those theoretical universes, he showed, time does not exist in our world either.

Einstein instantly recognized Gödel's paper as a breakthrough but an overwhelming majority of physicists, mathematicians and philosophers have spent the past half–century–plus trying to either ignore or find fault with Gödel's conclusion.

Neither strategy has succeeded.

Gödel's reasoning, compressed, was this: he could mathematically demonstrate a universe that was closed and rotated on itself.

In such a universe time travel was not only possible — it was inevitable.

If, in that universe, time was travel was possible, and by this Gödel meant precisely what you and I think of as time travel, i.e., the ability to go back and see the past as often as desired, then that past wasn't over: in fact, it never disappeared, since you could go back and find it whenever you liked, exactly as you can travel to Paris as often as you like and expect to find it there in all its reality.

Since the past was there, not having gone anywhere, then there was no such thing as time in the sense that we think of it passing, since nothing had passed at all — it was right there, always accessible.

From the book:

From his discussions late in life ..., it emerges that Gödel believed that the proper philosophy should capture axiomatically — though not purely formally — the fundamental concepts that underlie reality, which he took to include "reason, cause, substance, accidens [a traditional Latin term], necessity, value, God, cognition, force, time, form, content, matter, life, truth, idea, reality, possibility."

The goal of the great logician was not to make room in physics for one's favorite episode of "Star Trek," but rather to demonstrate that if one follows the logic of relativity further even than its father was willing to venture, the results will not just illuminate but eliminate the reality of time.

Gödel wrote, "I love everything brief, and find that in general the longer a work is, the less there is in it."

Gödel argued that if it was possible to return to one's past, then what was past never passed at all.

It is provable that time fails to exist in the Gödel universe.

It cannot, therefore, exist in our own: the final step is taken, and time really does disappear.

Odd, that I should have read the second half of this book in one sitting — or rather, one reclining, as my reading spot of choice (below, with the square red pillow bearing the indentation of my head)

requires assuming the [supine] position, with my legs covered with a chenille blanket and elevated on at least three pillows, thus returning as much oxygenated blood as possible to my cerebral cortex, which needs every last molecule it can get, trust me on this... but I digress — into the late hours, after watching Robert De Niro in John Frankenheimer's 1998 film "Ronin" on DVD.

Usually after a movie I go to bed, or read magazines or easy material, not books deconstructing the work of Kurt Gödel, considered by many the greatest logician and philosopher since Aristotle.

My smart time, if there is such a thing in bookofjoe world, is in the morning, as a rule: I get stupider as the day goes on.

But last night I was compelled to go at this book, and once I got going I was like a cat with fluffy furniture and no owner at home — I just couldn't stop until it was all done.