[extropy-chat] HISTORY: Solved & Unsolved Riddles

[scerir]

Another riddle: the universe.

I fwd the latest on Hawking (unfortunately
also on Derrida).

[Hey, J.R., where are you? Its your concept of universe!]

s.

> NOVEMBER 7 - 13, 2003
>
> Quark Soup
>
>
> Brain Worlds
> Hawking, Derrida and living with the other
> by Margaret Wertheim
>

> STEPHEN Hawking's voice driftsthrough the air, eerily familiar. These 
> are the synthesized vocal cords that attempted to explain to Homer 
> Simpson the nature of space and time, that joshed on the Star Trek 
> holodeck with Newton and Einstein. Along with the latter's shock of 
> hair, Hawking's computerized tones have come to symbolize the ideal of 
> Genius writ large. Yet the source of these sounds seems impossibly 
> small and fragile in the flesh. Bunched in his wheelchair at the front 
> of the room, Hawking is a man in miniature, his doll-like body in 
> hapless contrast to the gargantuan brain it supports.
>
> At the world's first "string cosmology" conference, held recently at 
> UC Santa Barbara, Hawking was expounding on his latest ideas about the 
> creation of the universe. It's a subject he famously catapulted to the 
> center stage of physics with his proof that space and time must have 
> begun with a singularity, a cosmic-scale version of a black hole. That 
> work was the subject of his Ph.D. thesis, and it built upon Einstein's 
> theory of relativity to demonstrate that any viable universe had to 
> have been born from a single, infinitely intense point - a kind of 
> cosmological seed. Hawking had come to Santa Barbara to revise 
> himself, presenting to an audience of fellow physicists a new model of 
> cosmic genesis which, as he explained, describes "a universe that 
> expands, contracts, bounces and expands again."
>
> Up close Hawking looks like an imp, an escapee from Lord of the Rings. 
> His delicate features are preternaturally enhanced by four decades of 
> living with Lou Gehrig's disease. Since I first interviewed him 18 
> years ago, he has visibly shrunk, but at this point it is a medical 
> miracle he is alive at all. It's his eyes that demand your attention, 
> as if the life force withdrawn from his body has concentrated in his 
> orbs. They don't just twinkle, they radiate light. Though he can 
> barely move anymore and must now be attended by a small army of 
> nurses, when he nods assent to a question, one senses the power of a 
> still-extraordinary mind at work. This combination of gymnastic 
> intelligence and immobile body creates a profound sense of otherness - 
> Hawking is as close to an alien among us as Mr. Spock, and every bit 
> as enigmatic.
>
> While he still believes in an original beginning, Hawking suggests 
> that since this cosmic birth our universe might have had many lives. 
> Think of a balloon that's inflated, deflated, then inflated again. 
> According to his new model, our particular space and time will 
> eventually end, but the universal whole will continue, carrying into 
> its next life a residue of its past repetitions.
>
> The impetus for Hawking's revision is the revolution that has 
> electrified the world of theoretical physics: string theory. Using the 
> mathematical putty of this theory, physicists are playing gods, 
> bringing forth from the pluripotent sea of their equations an 
> explosion of universes. At UCSB, string theorists served up visions 
> that contained not just one universe but multiple, expanding and 
> infinitely extending arrays of universes. There were "pocket 
> universes," "toy universes" and "baby universes" budding like spores 
> off parent universes - a dizzying plethora of possibility in which 
> almost any world that might be imagined was deemed to be happening 
> "somewhere."
>
> To its proponents string theory holds out the hope that this may be 
> the longed-for "theory of everything." To others, it seems a theory of 
> nothing. It is not even science, they argue. For as its greatest 
> exponents acknowledge, there is not a shred of evidence to support any 
> of its conclusions so far. Speaking on Nova the other night, Nobel 
> Prize-winning particle physicist Sheldon Glashow expressed his 
> feelings in scathing terms. "Let me put it bluntly," he said, "there 
> are physicists and there are string theorists." For Glashow, physics 
> is about experiment, and without experimental verification string 
> theory has no validity. Not since the Middle Ages has speculation so 
> exceeded the reach of observation. "Is this a theory of physics," 
> Glashow asked, "or philosophy?"
>
>
>
>
>
> WHATEVER string theory's epistemological status, it's hot. Glashow was 
> part of a Nova string theory special, PBS's most expensive science 
> project ever, a $3.5 million, three-part epic titled The Elegant 
> Universe. The series is based on the 1999 best-selling book of the 
> same name by Columbia University physicist Brian Greene, and PBS 
> honchos are clearly hoping it will be the next Cosmos, with Greene the 
> next Carl Sagan. "If string theory is right," Greene enthused giddily 
> at the start of the show, "we may be living in a universe where 
> reality meets science fiction."
>
> Certainly the producers seemed determined to distract us with all the 
> techniques of sci-fi cinema - there were more things flying at the 
> screen than in a Star Wars battle. Like Luke Skywalker, Greene seemed 
> to be continually dodging projectiles. He took the task in stride, for 
> he had evidently been schooled in The Crocodile Hunter style of 
> presentation. I half expected him to wrestle one especially annoying 
> graphic to the ground. Things whirled and whizzed and flashed; lights 
> pulsed, objects popped in and out of existence.
>
> Not that science shouldn't be spectacular. It's just that in the blitz 
> of special effects it was often hard to keep track of the ideas. It 
> was a relief whenever they cut to one of the physicists talking about 
> his work. Especially good was Nobel laureate Stephen Weinberg, whose 
> insights into why physicists care about this stuff helped to remind us 
> that science - even string theory - remains a deeply human pursuit, 
> driven by psychological needs and desires that all too often resist 
> rational reduction.
>
> 
>
> STRING theorists are excited, Weinberg noted, because their equations 
> suggest a path by which physics might be unified. For most of the past 
> century, physics has portrayed a disturbingly schizophrenic vision. On 
> the large scale, it describes the universe using Einstein's theory of 
> general relativity, but on the subatomic scale it reverts to the 
> wildly "other" perspective of quantum mechanics. General relativity 
> tells us how space and time behave on the celestial, or cosmological, 
> scale and ultimately gives us a picture of the universe as a whole. It 
> has made predictions tested to more than 40 decimal places of 
> accuracy, yet at the subatomic level it breaks down. Here, quantum 
> laws prevail and everything is ruled by laws of chance.
>
> At the cosmological level, things flow; in the subatomic realm they 
> jitter. Physicists like to use musical analogies, and we might say 
> that if general relativity describes a Strauss waltz, quantum theory 
> gives us a speed-metal riff. Practically speaking this duality has 
> little effect, but aesthetically it's profoundly unsatisfying. 
> Physicists cannot bear the bifurcation within their world picture; 
> they yearn for unity. At the Santa Barbara conference, David Berman, a 
> young English physicist from Hawking's department at Cambridge 
> University, took the musical theme further. In music, he told me, "You 
> can have two voices that sound discordant, then a third comes in and 
> resolves them into a harmonic whole." Physicists are searching for 
> this resolving voice, and in string theory they believe they might 
> have found their answer.
>
> Certainly, the universe has no trouble reconciling itself. The 
> schizophrenia is not in nature but in our mathematical models. It is 
> not the world that is fractured, but our understanding of it.
>
>
>
> ON THE DAY following Hawking's talk, UCSB hosted another intellectual 
> superstar, Jacques Derrida, at 73 the bad pensioner of French 
> philosophy. Derrida had been invited to speak at a conference on 
> religion, and his theme was living together, a subject he addressed 
> through the prism of his experience as a Jewish child growing up in 
> prewar Algeria. I had gone along to his sold-out lecture for entirely 
> separate reasons beyond my interest in string theory, but it turned 
> out there were uncanny resonances between the two events. The 
> organizing motif of Derrida's talk, the idea to which he returned 
> again and again (his singularity, as it were), was the notion of the 
> ensemble, or collection. Here, of course, he meant ensembles of people 
> - ethnic groups, religious communities, nation-states, local 
> neighborhoods, families and so on. But Derrida also wanted to alert us 
> to the French use of the word, its adverb sense, ensemble, as in 
> "vivre ensemble - living together."
>
> For Derrida the two senses of this one word were necessarily entwined. 
> Unity, he said, is an illusion. Ensembles are never homogeneous; 
> differences between members and parts of the whole will always exist. 
> Not just small differences, but radical dissimilarity. "Otherness," 
> Derrida insisted, is the norm, and we must learn to live with it. Even 
> within ourselves there is fragmentation. In Derrida's terms we are all 
> multiple beings, ensembles within. Accordingly, the demand for oneness 
> is a pathology we must renounce, for only by accepting the radical 
> "otherness" of others can we live in harmony with them. As he put it, 
> "Living together contests the closure of the ensemble."
>
> From a Derridian perspective, physicists' demand for a harmonic whole 
> takes on the cast of an unhealthy obsession. Insistence upon closure 
> is the very ideal he rejects.
>
> 
>
> STRING THEORY closes the chasm between relativity and quantum 
> mechanics by smoothing out the jitters of the subatomic realm, 
> replacing point particles with microscopic loops, or "strings." 
> According to the mathematical basis of this theory, everything in our 
> universe is made up of tiny vibrating loops of some fundamental 
> stringy stuff. Don't even ask what this might be - there is no answer. 
> Just accept the notion that at its most basic level the world is made 
> of minute rubber bands.
>
> But in order to get this theoretical unity, you have to be willing to 
> take on board a radical extension of the universe beyond all bounds of 
> human experience. According to string theory, these microscopic loops 
> require their own dimensions of space. In most currently popular 
> versions, strings vibrate in six dimensions, though in some versions 
> it is seven. All of these are additional dimensions tacked on to the 
> three dimensions of space and the one of time we normally encounter. 
> It is this aspect of string theory that its detractors so dislike. 
> Where are these dimensions?, they demand. What are they? How come we 
> don't see them?
>
> This last question, at least, has an answer. We don't see the extra 
> dimensions because they are too tiny to observe with any current 
> technology. On Nova, Brian Greene gave us an analogy: If an atom was 
> as big as our solar system, a string would be the size of a large 
> shrub. To detect something that small, you'd need a particle 
> accelerator the size of a galaxy.
>
> Strings aren't the only things the theory predicts. The other 
> revelation has been a class of objects called "branes," short for 
> membranes. Over dinner at the Santa Barbara conference, Joseph 
> Polchinski, from UCSB's hosting Kavli Institute for Theoretical 
> Physics, offered some illumination. Where strings exist at the 
> subatomic level, branes are the structures the theory generates on the 
> cosmological scale. Strings are tiny, branes are huge. If strings are 
> like spaghetti, branes would be vast sheets of lasagna. Our universe, 
> according to the theory, is a brane, a cosmic-scale incarnation of the 
> same fundamental stringy substance. "You can ask what branes are made 
> of," Polchinski said, "but they're not made of anything. They're just 
> the stuff the theory describes."
>
> While strings suggest a subatomic space that has yet to be detected, 
> branes conform to some of our usual spatial conceptions. The brane of 
> our universe is said to have the accepted dimensions of space and 
> time. Yet it is seen as just one potential part of a much larger 
> five-dimensional realm known as "the bulk." Within the bulk, 
> Polchinski told me, there may well be other branes. Here "the 
> universe" becomes not just our brane but the total set of branes 
> within the bulk-space.
>
> String theory does not stop there. In Hawking's version, an individual 
> brane can be continually reborn. Other versions allow the possibility 
> of branes that spawn from prior branes or infinitely foaming seas of 
> branes, like a vast cosmological head of beer. In Santa Barbara, 
> Leonard Susskind, one of the pioneers of string theory, presented an 
> alarmingly fecund vision in which there were hundreds of "dimensions" 
> of potential universes, with new ones coming into being all the time. 
> Spaces upon spaces upon spaces, a multiplication of possibilities that 
> defy the very notion of limit.
>
> Although some physicists have objected to the almost organic 
> proliferation that string theory allows, Derrida, I think, would be 
> pleased by this explosion of ideas, which supports in the totality of 
> its weirdness the fundamental theme of his talk.
>
> 
>
> With his impeccable tailoring and leonine presence, the most 
> controversial philosopher of our time would command attention even if 
> he wasn't supported by the buttress of fame. Derrida told us that the 
> "commandment" to live together imposes upon us demands "beyond law and 
> nature." Law, he said, is never sufficient to dictate our actions, 
> which operate in a wider realm of possibility than the statutes of any 
> legal system. Derrida urged us to embrace this "excess," to live and 
> love in a broader field of potential. And that is what I like so much 
> about the new string cosmologies. Despite physicists' desire for 
> oneness, in the end their equations also have multiplied the 
> possibilities, giving us a vast domain of potential in which the 
> "natural laws" here on Earth are just one set among many. It is as if 
> nature itself resists efforts to press it into a single mode, joining 
> Derrida on the path of radical multiplicity. Whether we can prove the 
> existence of these alternate worlds seems of little consequence.
>
> In string theory we have discovered a language which may well be more 
> lyrical than empirical, but which, in that very quality, enables us to 
> contemplate a wild excess of other options. Derrida and Hawking - the 
> physicist and the philosopher - would, I believe, have embraced one 
> another.
>