The timeless universe of Julian Barbour

Bookshops and public libraries are powerful attractors in my life: hardly a day passes by without a fleeting visit to these cornucopias of information and dreams. Friday was no exception: I was at Borders loafing about, and I ended up in the Physics section. My trained eye spotted an interesting title within seconds: The End of Time, by Julian Barbour. I had vaguely heard of the fellow before, through some readings on the interpretation of Quantum Mechanics and on Quantum Gravity. Barbour, I seemed to recall, does not believe in Time. He in not alone, mind you: Melissus, Nagarjuna, Plotinus, McTaggart, and numerous others were also vocal disbelievers. But there is a difference: Dr. Barbour is a theoretical physicist, and physicists (with some notable exception, such as the Loop Quantum Gravity folks) assume space-time as the background where physics happens.

What kind of universe does Barbour envision? His world, which he cleverly christened Platonia, is a world of Nows (by the way, Platonia is also the name of his web site). Each Now is a possible configuration of the entire universe, complete in itself, and static (think of a single photo snapshot). How are Nows concatenated to one another? They aren't. Quite simply, there is notion of similarity describing how far apart two Nows (i.e. two universe's configurations) are. Some photos look similar, others do not. By arranging a list of contiguous Nows, one gets a factitious timeline, a bit like arranging photo grams one gets a movie (notice that you could arrange the deck in more than one manner).

All right, but how come we do experience the flow of time? Here is a clever move by Barbour (as matter of fact, a few others, like Emanuele Severino in Destino della Necessita', had a similar argument, albeit from a different angle). It is called time capsule. A time capsule is a special type of Now, containing some data that appear like traces of other Nows, or fragments of recorded history. Thus, in his view, there is no flow whatsoever, only we (you and I) are inside the same time capsule that suggests the existence of past & future.

Crazy? Not really. After all, what do we know about past and future? Only what our memory and our imagination tell us. No more, no less.

Summing up, Julian Barbour brings us back to the number 3 instead of the Minkowskian 3+1 =4. Space is real, time is not (*). Instead of increasing dimensions, like String theorists do, he reduces them by one. He kills Time.

Allow me to add a coda here, before quitting. I like all of the above, so much so that in my book on Time a section will be dedicated to charting the charming land of Platonia. However, I have a gut feeling that this is a great start, but not the entire story. Perhaps space too is not that real after all. Perhaps we live in a space-time capsule, and the entire vast expanse of this universe is no more than a mad game of mirrors within mirrors. Perhaps the basic ingredients of reality are not Nows, but a multiplicity of Here-And-Nows, hic et nunc. Perhaps....

(*) A note for the math-savvy: I hope my sentence above hasn't mislead anyone into believing that Barbour's universe is R^3. It is not; his kosmos is the so-called configuration space, whose dimension depends on how many entities there are. For instance, if there were only 3 particles, our physical universe would be the manifold whose points are the different configurations of a three-body system. As you can see, it is a pretty roomy house...

PS After coming back home, I chased Barbour all over the net. He appears in a riveting 1/2 hour video, which I truly liked. It is called Killing Time: enjoy.

Sherlock Holmes on Decluttering

A few days ago an acquaintance of mine suggested a post on decluttering, after I had been extolling its broad benefits at all levels of the human ladder: physical, emotional, mental & spiritual. I shall candidly avow that by nature and by inured habits I tend to be a hoarder, so only quite recently I came to realize the importance, indeed the absolute necessity of letting go.

At the very moment when I decided to follow through with the cited suggestion, a chunk of memory emerged rather abruptly to the surface of my consciousness: it was none less than an entire passage from A study in Scarlet, first novel of the wildly successful Sherlock Holmes series.

To be sure, I could not recollect the exact words, only their gist and flavor, but a quick look up over the net came to rescue (I was away from home, where on my library's shelves loom large the two stately volumes of The Annotated Sherlock Holmes). Here is Doyle's text, in all its sparkling elegance and wit:

-His ignorance was as remarkable as his knowledge. Of contemporary literature, philosophy and politics he appeared to know next to nothing. Upon my quoting Thomas Carlyle, he inquired in the naivest way who he might be and what he had done. My surprise reached a climax, however, when I found incidentally that he was ignorant of the Copernican Theory and of the composition of the Solar System. That any civilized human being in this nineteenth century should not be aware that the earth travelled round the sun appeared to me to be such an extraordinary fact that I could hardly realize it.

"You appear to be astonished," he said, smiling at my expression of surprise. "Now that I do know it I shall do my best to forget it."
"To forget it!"
"You see," he explained, I consider that a man's brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it. Now the skillful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order. It is a mistake to think that that little room has elastic walls and can distend to any extent. Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones."
"But the Solar System!" I protested.
"What the deuce is it to me?" he interrupted impatiently: "you say that we go round the sun. If we went round the moon it would not make a pennyworth of difference to me or to my work."

As you can see, there is more to decluttering than getting rid of that nasty heap of junk mail on the couch. This often neglected activity must be quietly and persistently carried out across the board, day by day: everything that is not useful must be disposed of, not excluded bad habits, stale friendships, ill-digested information, and, of course, physical trash.

Decluttering is a large component of the subtle metabolism of life: let us thus boldly embrace it, and we shall feel healthier, lighter and smarter too, voire the inimitable and unforgettable Mr. Holmes.

Mathematician and Art Collector

In the aftermath of his passing (January 30th 1998), two tight and a bit idiosyncratic communities independently mourned Professor Samuel Eilenberg: mathematicians and art collectors said goodbye to one of their brightest stars.

For several decades this remarkable man had shifted, with no apparent effort, back and forth between two worlds as far apart as our modern compartmentalized culture would permit: in the first one, populated with commutative diagrams, abelian groups, towers of topological spaces, he was simply and only Sammy to everyone. In the other he painstakingly bought, sold, exchanged, assessed Burmese statuettes, Chinese ceramic, south east Asia religious artifacts of all kinds and sorts, all the while being known as the Professor. And professor he certainly was, but of what? Of math, of course, but I bet you that most of his fellow dealers wouldn't know, and wouldn't care either. He was The Professor, a darn good dealer.

I hear a voice rising:- What is the big deal? Aren't there thousands of individuals out there having a career and a hobby? - Well, sure there are, but there is a difference, a big difference, in fact two big differences.

First, Eilenberg was extremely successful at both. As a mathematician he literally changed the course of many fields of research, not to mention the fact that he was also at the very heart of countless initiatives and relentlessly promoting a mathematical enterprise of gargantuan proportions. In art, starting from virtually nothing (he immigrated in a rush from his native Poland, fleeing the Nazis), he built a unique collection worth several millions at the time of his donation to the Metropolitan Museum of Art in NYC.

Second, he tried (and apparently succeeded remarkably well) to keep his two identities as separated as he could. He was two-in-one-body: a Mathematician and an Art Collector.

How did he manage to handle his dual life? What was the hidden thread between the two passions that ruled his life? What kind of mind shift (if any) did he need in sliding from one world to the next? Why did he keep his two roles so far apart?

So many questions....

Few weeks ago I called one of his students, asking for answers. There was only one: -I am afraid I cannot help. Sammy did not volunteer any information- To be sure I expected it, but I have to confess I was a bit disappointed. Somehow, I was still clinging to the tenuous hope that the veil would be lifted and I could peep inside Sammy's mysterious life...

In the last few years, after a long neglect, laymen books on mathematicians and outstanding math problems have cropped up at a steady pace (who hasn't heard of A beautiful Mind? ). I hope that someone, with a lot of time available and a good deal of patience (a bit of detective skills wouldn't hurt), will inquire into Sammy's story and write it down for the rest of us.

Till then, we are left with a great mathematical legacy, and a treasure trove at the Metropolitan Museum. Till then, we can just think one more time of a truly enigmatic man:

Sammy Eilenberg, Mathematician & Art Collector.


PS The photo of Sammy with his penetrating & pensive eyes at the top of this post renders full justice to the man (I know, as I was under his scrutiny for 30 very long seconds). However, there was another side of him, lighter, brighter, and a bit ironic too, as marvellously witnessed by this great pic at a Math Conference, in 1992 (please notice the big cigar & the exotic ring).