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But what I really want to talk about is INTERSTELLAR (Spoiler review)

December 3, 2014 1 comment

I finally went to see Christopher Nolan’s Interstellar yesterday. I didn’t get the full IMAX experience; only one theater in reach is showing it that way, and I wanted to go to a different theater so that I could visit a couple of stores nearby. But it was still an impressive experience. There is a lot I love about the film, although it has some significant flaws. I tend to agree with a lot of the reviews I’ve seen that certain ideas in the climax really stretch credibility and take one out of the film, which is a problem for a movie that, for the most part, is very heavily grounded in credible science.

The premise of the film is one that feels familiar from a lot of science fiction I’ve read — which is a good thing, given how rarely cinematic sci-fi feels like it engages the same kind of ideas as science fiction literature. The world is dying, and the heroes of the film are scientists and explorers trying to save the human race. The drama comes largely from the clash between the commitment of the protagonists — including Cooper (Matthew McConaughey), Brand (Anne Hathaway), and her father Dr. Brand (the inevitable Michael Caine) — to exploration and human survival and the more intimate, personal concerns of the people they leave behind, notably Cooper’s daughter Murph (Mackenzie Foy as a child, Jessica Chastain as an adult). There are also conflicts arising from the dispute over whether to place rescuing a loved one over the greater needs of the mission, with the conflict generated by the physical and engineering constraints of the situation, and from the profound isolation that drives the film’s main antagonist Dr. Mann (Matt Damon, who seemed to eschew major billing and whom I was surprised to see in the film) to his desperate actions. So even the character drama is mostly (mostly) placed in the context of thoughtful, plausible scientific scenarios, and that was good to see.

There was so much science here that was awesome to see onscreen at last. I loved the portrayal of the wormhole and the dialogue explaining why it has a spherical mouth instead of the cliched funnel shape. It was amazing to see an accurate version of a wormhole portrayed onscreen for once (although the sequence of passage through the wormhole seemed more visually fanciful). I loved the realistic treatment of the spaceships and their physics, and — as in Gravity — I loved, loved, loved the lack of sound in the space scenes. I’ve come to realize that silence can make things feel more real, and not only in space. Even here on Earth, we often see news footage or surveillance-camera footage that’s soundless, or observe something live from a great enough distance that we can’t hear it. So seeing something without hearing it, without a carefully honed accompaniment of clearly audible sound effects, can make it feel more like a real event and less like a constructed artifice. I had the same reaction to the shot of the Endurance passing by Saturn, visible only as a distant point of light. I gasped in awe at that, because the very absence of clarity and detail made it feel like I was looking at the real thing rather than a constructed special effect.

The reason there’s so much good science is because Nolan made the film in cooperation with Kip Thorne, the physicist whose work on wormholes for Carl Sagan’s novel Contact led him to a whole new field of wormhole physics that improved our understanding of general relativity and the way it could apply in extreme situations. This is taking that kind of collaboration to the next level, since Thorne was actually an executive producer on the film and was involved in every level of building the story. So there is so much good science and effective science exposition — naturally a bit simplified for movie audiences, but nothing that really felt badly wrong or misunderstood by the screenwriters. Even areas other than physics were well-handled. I gather that the filmmakers met with a team of biologists to work out a plausible mechanism for the blight that’s killing all the crops on Earth. And it was so refreshing to see cryogenic pods that didn’t have big windows that would let tons of heat in, that were more like realistic deep-freeze units.

But all that good science made it harder to tolerate the more fanciful moments, the parts that Nolan apparently considered non-negotiable and that Thorne had to compromise on as best he could. The severity of the time dilation on the ocean planet near the black hole was hard to justify, although apparently Thorne found an equation that made it just barely believable. The second planet they visited was just plain weird… so, it’s… made of clouds of solid ice, and has no surface? It’s just some kind of spongy ball of ice? And yet it has 80 percent of Earth’s gravity? There’s just no way that works. Even if such a body could form, if it were so low in density, it would never have gravity anywhere near that high. And it’s more likely that it would condense into a more solid ball of ice. This was just weird. Thorne has said it’s the part he’s most unhappy with.

Also, I’m disappointed that a movie nominally about the wonders of exploration doesn’t give us more interesting environments. We get a bunch of ocean and a bunch of ice, and that’s about it. So monochrome! Apparently the earlier draft by screenwriter Jonathan Nolan had more planetary exploration and even aliens, but director Nolan stripped most of it out.

Oh, and how was that NASA facility supposed to work as a centrifuge if it ever launched? All those vertical columns next to the walls would become big horizontal obstructions at chest level.

But the climax of the film is what really pulled me out of the story, and here’s where we get into the heavy spoilers. So Cooper falls into the black hole — okay, there was Thorne-guided dialogue explaining reasonably why it was the kind of black hole that could allow a survivable entry — and ends up in a tesseract spacetime manifold constructed by the 5-dimensional “bulk beings” that are actually the far-future evolved descendants of humanity reaching back to help us save ourselves. Okay, I can buy that conceit. And I can buy the premise that only gravity can cross the dimensions and transcend time, which is why the bulk beings could only send Cooper and the robot TARS back to Sol System in the relative present and could only send a message back in time. (String theory says that most kinds of particle/string are attached to the 4-dimensional brane of our universe, but gravitons are detached from it and can leak through to other universes, which may be why gravity is so weak.) But still, that’s something I had to reason out after the fact. As it was presented — Cooper just magically turning out to be the “ghost” and sending cryptic messages to Murph through “gravity” — it felt silly and fanciful. Thorne did his best to ground Nolan’s idea in some kind of plausible context, but it’s hard to believe that a force as weak as gravity could be focused tightly enough to have the fine-scale effects shown in Murph’s room. More to the point, even if it can be justified physically in terms of Sufficiently Advanced Technology for 5-dimensional gravity control and spacetime manipulation, there’s the deeper question of why. Why employ such convoluted methods to send the quantum data to Murph? Couldn’t the bulk beings just send the message directly instead of setting up this contrived father-and-daughter-connecting-across-time situation? The only excuse I could think of as I walked back to my car after the movie was that maybe they were so far in the posthuman future that they no longer remembered our languages and communication methods and thus needed a human intermediary to interpret for them. But then, how were they able to communicate to TARS sufficiently that he could explain the situation to Coop? And why couldn’t TARS transmit the data? It felt like Nolan’s intent was to build on Brand’s earlier speech about love being a force that could transcend time and space, that it was only Coop’s love for his daughter that let him connect. But as a number of other critics have said, that’s sentimental silliness in the context of such a hard-science film. It’s a maudlin, corny scenario that just doesn’t feel right, and it’s a shaky foundation for an otherwise mostly solid film.

On top of which, how the hell did adult Murph figure out that it was her father communicating with her? There was no evidence presented to her that would’ve let her make that deduction. She just magically knew it because the timing of the montage demanded that she recognize it at the same time the audience did. It’s the one part where there wasn’t even an attempt to assert some kind of rational justification for the sentimental situation, and the worst part of the sequence. Heck, it wasn’t even justified from a character standpoint. For all these years, she’s felt that her father abandoned her. Why would she suddenly, based on nothing but the Morse-code “STAY” that she’d already known about at age 10, do a total about-face in her perceptions and suddenly believe that her father had been sending her messages from the future all along? Where the hell does that come from, either as an intellectual leap or an emotional epiphany? The only reason she got there was because the script made her do it. That’s as dishonest from a character standpoint as it is from a plausibility standpoint.

And that’s a shame, because the visual portrayal of the tesseract is brilliant. It’s unlike anything I’ve seen onscreen before, and it’s a marvelous visualization of the idea of time as a traversable dimension, although I could quibble about the details.

There’s one other area where the film’s realism failed badly, and it’s more disturbing. This film is set in the United States sometime in the future, probably the latter half of the 21st century. By then, demographic trends suggest that the US is going to be a white-minority nation. I’m sure that the current pool of physicists, engineers, and astronauts working for or with NASA is already highly diverse today. And yet the cast of this film was overwhelmingly white. There were only two black characters in the film, a school principal who appeared in a single scene and a token member of the expedition who stayed behind on the ship on the first landing and then got killed off at the midpoint. The only vaguely positive thing that can be said is that at least the black guy was the second one killed off instead of the first. Other than that, there were only a couple of uncredited bit players in the background. And the only Asian face I noticed in the film was a photo of one of the missing astronauts, one they didn’t bother to rescue. I don’t think there were any Hispanic characters in the film at all. The robots got more screen time in this movie than anyone nonwhite. This is a story about the survival of all humanity, yet virtually the only humans given any agency or participation in the story are white people with Anglo-Saxon names. In a film that strives for realism on so many levels, this is a gross failure of plausibility and common sense. I’m sick of the Hollywood establishment being so out of step with reality when it comes to inclusion in feature films. Television is increasingly catching up to reality as executives realize that their audience is diverse and they can make more profit by appealing to that diversity. But movie executives still apparently haven’t caught on.

On a more positive note, I wanted to commend Hans Zimmer’s score. As I’ve remarked before, I find Zimmer a chameleonic composer that I have a mixed response to; he’s good at adapting to what different directors want, so sometimes I find his work brilliant and fascinating, yet on other films I really don’t like it at all. I really disliked his work on Nolan’s Batman films, Inception, and the Nolan-produced Man of Steel, finding those scores ponderous and blaring, so I wasn’t expecting to like his score for Interstellar. But it’s actually very good. It’s in kind of a Philip Glass-y, minimalist vein, but it works well for the film. I’m glad that it ends up being another tick in the plus column for the film rather than adding another minus.

All in all, then, Interstellar is a film that mostly works as an installment in the all too small but growing category of hard-science fiction motion pictures. It’s more successful than Gravity at being believable, and hopefully it will add momentum to the trend of SF films getting more grounded in real science. In many ways, it’s a refreshing treat for fans of physics and hard SF. But it has a couple of major flaws that are hard to get past, especially for fans of physics and hard SF.

Musings on quantum gravity

Recently I came across this article about an experiment to reconcile quantum physics with gravity, the one fundamental force that hasn’t yet been explained in quantum terms:

New Experiments to Pit Quantum Mechanics Against General Relativity

The problem with reconciling gravity (which is explained by Einstein’s General Theory of Relativity) and quantum physics is that they seem to follow incompatible laws. Quantum particles can exist in superpositions of more than one state at a time, while gravitational phenomena remain resolutely “classical,” displaying only one state. Our modern interpretation suggests that what we observe as classical physics is actually the result of the quantum states of interacting particles correlating with each other. A particle may be in multiple states at once, but everything it interacts with — including a measuring device or the human observer reading its output — becomes correlated with only one of those states, and thus the whole ensemble behaves classically. This “decoherence” effect makes it hard to detect quantum superpositions in any macroscopic ensemble, like, say, a mass large enough to have a measurable gravitational effect. Thus it’s hard to see quantum effects in gravitational interactions. As the article puts it:

At the quantum scale, rather than being “here” or “there” as balls tend to be, elementary particles have a certain probability of existing in each of the locations. These probabilities are like the peaks of a wave that often extends through space. When a photon encounters two adjacent slits on a screen, for example, it has a 50-50 chance of passing through either of them. The probability peaks associated with its two paths meet on the far side of the screen, creating interference fringes of light and dark. These fringes prove that the photon existed in a superposition of both trajectories.

But quantum superpositions are delicate. The moment a particle in a superposition interacts with the environment, it appears to collapse into a definite state of “here” or “there.” Modern theory and experiments suggest that this effect, called environmental decoherence, occurs because the superposition leaks out and envelops whatever the particle encountered. Once leaked, the superposition quickly expands to include the physicist trying to study it, or the engineer attempting to harness it to build a quantum computer. From the inside, only one of the many superimposed versions of reality is perceptible.

A single photon is easy to keep in a superposition. Massive objects like a ball on a spring, however, “become exponentially sensitive to environmental disturbances,” explained Gerard Milburn, director of the Center for Engineered Quantum Systems at the University of Queensland in Australia. “The chances of any one of their particles getting disturbed by a random kick from the environment is extremely high.”

The article is about devising an experiment to get around this and observe a superposition (potentially) in a “ball on a spring” type of apparatus. What interests me, though, is a more abstract discussion toward the end of the article.

Inspired by the possibility of experimental tests, Milburn and other theorists are expanding on Diósi and Penrose’s basic idea. In a July paper in Physical Review Letters, Blencowe derived an equation for the rate of gravitational decoherence by modeling gravity as a kind of ambient radiation. His equation contains a quantity called the Planck energy, which equals the mass of the smallest possible black hole. “When we see the Planck energy we think quantum gravity,” he said. “So it may be that this calculation is touching on elements of this undiscovered theory of quantum gravity, and if we had one, it would show us that gravity is fundamentally different than other forms of decoherence.”

Stamp is developing what he calls a “correlated path theory” of quantum gravity that pinpoints a possible mathematical mechanism for gravitational decoherence. In traditional quantum mechanics, probabilities of future outcomes are calculated by independently summing the various paths a particle can take, such as its simultaneous trajectories through both slits on a screen. Stamp found that when gravity is included in the calculations, the paths connect. “Gravity basically is the interaction that allows communication between the different paths,” he said. The correlation between paths results once more in decoherence. “No adjustable parameters,” he said. “No wiggle room. These predictions are absolutely definite.”

Now, this got me thinking. Every particle with mass interacts gravitationally with every other particle with mass, so there would be no way to completely isolate them from interacting. For that matter, gravity affects light too. So if gravity is an irreducible “background noise” that prevents stable superpositions, that would explain why quantum effects don’t seem to manifest with gravitational phenomena.

And that does sort of reconcile the two. The decoherence model, that classical states are what we get when quantum states interact and correlate with each other, basically means that classical physics is simply a subset of quantum physics, the behavior of quantum particles that are in a correlated state. So the “classical” behavior of gravity would also be a subset of quantum physics — meaning that relativistic gravity is quantum gravity already, in a manner of speaking. We just didn’t realize they were two aspects of the same overarching whole.

Now, this reminds me of another thing I heard about once, a theory that gravity didn’t really exist. It might have been the entropic gravity theory of Erik Verlinde, which states that gravity is, more or less, just a statistical artifact of particles tending toward maximum entropy. Now, what I recall reading somewhere, though I’m not finding a source for it today, is that this — or whatever similar theory I’m recalling — means that particles tend toward the most probable quantum state. And statistically speaking, for any particle in an ensemble, its most probable position is toward the center of that ensemble, i.e. the center of mass. So I had the thought that maybe what we perceive as gravity is more just some sort of probability pressure as particles tend toward their most likely states.

Now, if Stamp’s theory is right, then Verlinde’s is wrong; there must be an actual force of gravity, or rather, an interaction that correlates the paths of different particles. But it occurs to me that there may be some basis to the probabilistic view of gravity if we look at it more as a quantum correlation than an attraction. To explain my thinking, we have to bring in another idea I’ve talked about before on this blog, quantum Darwinism. The idea there is that the way decoherence works is that the various states of a quantum particle “compete” as they spread out through interaction with other particles, and it’s the more robust, stable states that prevail. Now, what I’m thinking is that as a rule, the most stable states would be the most probable ones. And again, those would tend to be the positions closest to the center of mass, or as close as feasible when competing with other particles.

So if we look at gravitation not as an attractive force per se, but as a sort of “correlational field” that promotes interaction/entanglement among quantum particles, then we can still get its attractive effect arising as a side effect of the decoherence of the correlated particles into their most probable states. Thus, gravity does exist, but its attractive effect is fundamentally a quantum phenomenon. So you have quantum gravity after all.

But how to reconcile this with the geometric view of General Relativity, that gravity is actually a manifestation of the effect that mass and energy have on the topology of spacetime? Well, that apparent topology, that spatial relationship between objects and their motions, could be seen as a manifestation of the probabilistic relationships among their position and movement states. I.e. a particle follows a certain path within a gravitational field because that’s the most probable path for it to take in the context of its correlation with other particles. Even extreme spacetime geometries like wormholes or warp fields could be explained in this way; an object could pass through a wormhole and show up in a distant part of space because the distribution of mass and energy that creates the wormhole produces a probability distribution that means the object is most likely to be somewhere else in space. Which is analogous to the quantum tunneling that results because the peak of a particle’s probability distribution shifts to the other side of a potential barrier. And for that matter, it has often been conjectured that quantum entanglement between correlated particles could be caused by microscopic wormholes linking them. Maybe it’s the other way around: wormholes are just quantum tunneling effects.

One other thought I’ve had that has a science-fictional impact: if gravitation is a “correlational quantum field” that helps the most probable state propagate out through the universe, that might argue against the Many-Worlds Interpretation of quantum decoherence. After all, gravity is kind of universal in its effect, and the correlation it creates produces what we see as classical physics, a singular state. It could be that coherent superpositions would only happen on very small, microscopic scales, and quantum Darwinism and gravitational correlation would cause a single consensus state to dominate on a larger scale. So instead of the whole macroscopic realm splitting into multiple reality-states (timelines), it could be that such splitting is only possible on the very small scale, and maybe the simmering of microscale alternate realities is what we observe as the quantum foam. It could be that the MWI is a consequence of an incomplete quantum theory that doesn’t include gravity, and once you fold in gravity as a correlating effect, it imposes a single quantum reality on the macroscopic universe.

Which would be kind of a bummer from an SF perspective, since alternate realities are useful story concepts. I’d just about come around to believing that at least some alternate realities might be stable enough to spread macroscopically, as I explained in my quantum Darwinism essay linked above. Now, I’m not so sure. The “background noise” effect of gravity might swamp any stable superpositions before they could spread macroscopically and create divergent timelines.

However, these thoughts might be applicable to future writings in my Hub universe (and as I’ve discussed before, I’ve already given up on the idea of trying to reconcile that with my other universes as alternate timelines). The Hub is a point at the center of mass of the greater galaxy — i.e. the system that includes the Milky Way proper, its satellite galaxies, and its dark-matter halo — that allows instantaneous travel to any point within that halo. I hadn’t really worked out how it did so, but maybe this quantum-gravity idea provides an answer. If gravity is quantum correlation, and all particles’ probability distributions tend toward the center of mass, then maybe the center of mass is the one point that allows quantum tunneling to the position of every other particle. Or something like that. It also provides some insight into the key McGuffin of the series, the fact that nobody can predict the relationship between Hub vectors (the angle and velocity at which the Hub is entered) and arrival destinations, meaning that finding new destinations must be a matter of trial and error. If the Hub works through quantum gravity and correlation with all the masses within the halo, then predicting vectors would require a complete, exact measurement of the quantum state of every particle within the halo, and that would be prohibitively difficult. It’s analogous to how quantum theory says that every event in the universe is already part of its wave equation, but we can’t perfectly predict the future because we’d need to know the entire equation, the behavior of every single particle, and that would take an eternity to measure. So it’s something that’s theoretically deterministic but functionally impossible to determine. The same could be true of Hub vectors.

Although… we’re only talking about one galaxy’s worth of particles, which is a tiny fraction of the whole universe. So maybe it’s not completely impossible…

Anyway, those are the musings I’ve had while lying awake in bed over the past couple of early mornings, so maybe they don’t make much sense. But I think they’re interesting.

Hints of Higgs? Maybe…

The big science news today is the announcement of the latest results from the Large Hadron Collider”s search for the elusive Higgs boson, and while the results are far from conclusive so far, they’re actually mildly encouraging.  Two independent detectors got pretty much consistent results suggesting the possibility of a particle with a mass somewhere around 125 GeV.  (That’s giga electron volts — since E=mc^2, physicists measure particle mass in units of energy.)

Here’s the New York Times piece on the news, including links to the raw data published on a site called TWiki (whose motto is probably not “bidi-bidi-bidi”).  Here’s a more detailed article from New Scientist.  However, the most useful link I’ve come across is this Higgs FAQ from the blog of particle physicist Matt Strassler.  I’ve never quite understood what all this Higgs field/particle business was all about until recently, but I’m starting to get a handle on it now.  The FAQ does a good job of explaining the Higgs field and its role, and why not finding the Higgs particle would be just as intriguing and useful a result as finding it.  (Because the particle isn’t the key, it’s just the simplest and only known way of detecting the Higgs field, which is the thing that’s actually important.  And if there were no particle, it would just mean the field is different than the simplest model suggests, or that it works in a different way, not that it didn’t exist.)

So nothing conclusive today, but interesting hints that will be pursued further.  Apparently they’ll be able to confirm or deny this evidence by next summer, and if it doesn’t pan out, they’ll try something else when the LHC reaches full power in 2015.

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Thinking about other universes (or, the trouble with infinities)

December 8, 2011 8 comments

I’ve been mulling over another subject that was suggested by the recent NOVA miniseries “The Fabric of the Cosmos,” hosted by physicist Brian Greene based on his book of the same name.  I felt some of the ideas it put across were too fanciful, putting sensationalism over plausibility or clarity, and one of them was the topic of its concluding episode, “Universe or Multiverse?”

The premise of that episode was that, if the Big Bang happened as the result of localized symmetry-breaking in an ever-inflating realm of spacetime, then our universe could be just one “bubble” in a perpetually expanding cosmic foam, with other universes being separate “bubbles” with their own distinct physics and conditions, forever out of reach because the space (how many dimensions?) between us and them is forever expanding.  Now, that’s okay as far as it goes.  It’s a somewhat plausible, if untestable, notion given what we currently know.  But what Greene chose to focus on was a rather outre ramification of this: the idea that if the multiverse is infinite, if there’s an infinite number of other universes alongside ours, then probability demands that some of them will be exact duplicates of our universe, just happening by random chance to have the exact same combination of particles and thus producing the same galaxies, stars, planets, species, inviduals, etc. — kinda like how the famous infinite number of monkeys banging on an infinite number of typewriters will inevitably produce all great literature by chance.  Thus, so the claim went, there could be other universes out there that are essentially parallels to our own with duplicates of ourselves, except maybe for some minor variations.  (Or maybe universes where duplicate Earths and humans exist in different galaxies, or where a duplicate Milky Way coexists with a different configuration of galaxies, or all of the above.)

Note that this is entirely different from the concept of parallel timelines, the usual way of generating alternate Earths in science fiction.  Parallel timelines aren’t separate universes, despite the erroneous tendency of SF to use the terms interchangeably.  They’re coexisting quantum states of our own universe.  The idea is that just as a single particle can exist in two or more quantum states at the same time, so can the entire universe.  These alternate histories would branch off from a common origin, and thus it’s perfectly reasonable that they’d have their own Earths and human beings and the same individuals, at least if they diverged after those individuals were born.  And there’s at least the remote possibility of communication or travel between them if nonlinear quantum mechanics could exist.  What we’re talking about here is something else altogether, literal other universes that just happen by random chance to duplicate ours because it’s inevitable if there’s an infinite number of universes.  While parallel timelines would be facets of the same physical universe we occupy, and would thus essentially be overlapping each other in the same place, these duplicate universes would be unreachably far away, except maybe by some kind of FTL or wormhole technology if such a thing could ever exist.  And they might predate or postdate our own universe by billions of years.

But I think it was a flawed conceit to dwell on that aspect of the multiverse idea, and I have my problems with the reasoning employed.  For one thing, it’s purely an ad hoc assumption that the multiverse is infinite rather than finite.  If it’s finite, then there’s no guarantee that there would be other universes that exactly duplicate ours.  Certainly there could be ones with compatible physical laws, with their own stars and galaxies and planets and life forms, but odds are they’d be different planets, different species, different individuals.  No duplicate Earth, no duplicate Lincoln or Kennedy or Jet Li.

And if the multiverse is infinite, then sure, you could argue that with an infinite number of tries, it’s inevitable that our universe would be exactly duplicated somewhere.  But the flip side to that argument is that if there’s an infinite number of universes, then the odds that any given universe would duplicate ours would be n divided by infinity, or effectively zero.  In practical terms, if we found a way to visit other universes via wormholes or something, then we could search for an infinite amount of time before finding one that had its own Earth and human race and history duplicating ours except for having more goatees or whatever.  Thus, by any realistic standard, such duplicates would be effectively nonexistent. (This is the problem with infinity as a concept in science — it tends to lead to absurdities and singularities.  Physicists generally try to avoid infinities.)  So while that result (the existence of duplicate universes) might be a logically sound consequence of the premise of an infinite multiverse, it’s also a trivial result, one that has no practical meaning and can’t be proven or falsified.  So it’s not science, just sophistry.  It’s angels dancing on the head of a pin.  And that makes it a waste of time to focus on in a program that’s supposed to be about science.

Besides, it’s boring.  The show presented us with the prospect that there could be an infinite number of possible forms for universes to take, whole other sets of physical laws, an unlimited range of possibilities… and all they wanted to talk about was duplicates of the world we already know?  What a staggering failure of imagination — or what a staggering triumph of self-absorption.  I would’ve been far more interested in hearing about the endless variety of universes that weren’t just like ours.  Why not dazzle the viewers with some discussion about what physics would be like in a universe with more than three spatial dimensions?  Or one with a higher or lower speed of light?  That would’ve been so much cooler and more enlightening than the silly, dumbed-down examples they gave, like Earth with a ring around it or Brian Greene with four arms.

I suppose the one appeal of the infinite-monkeys premise is metafictional: You can use it to argue that if every remotely possible combination or interaction of particles is inevitable, then every fictional universe really happens somewhere.  So, for instance, I could claim that my various fictional universes — my default/Only Superhuman universe, the Hub universe, the “No Dominion” universe, whatever else I might eventually get published — all coexist in the greater multiverse, and their different physical rules, different principles of FTL and whatever, could be explained by subtle variations in the laws of physics of their distinct universes (and yet somehow don’t prevent the fundamental interactions, dark energy, and so forth from having the exact same values so that stars and planets and life can form the same way).  And it’s handy for fans who want to believe that, say, a crossover between Star Trek and Transformers, or Star Wars and Firefly, or whatever might be possible despite the huge differences in those universes’ histories and physics.  But I’m not sure I find it desirable.  To me, if there’s some planet in some unreachably distant universe that exactly duplicates Earth’s evolution and history, and has a duplicate of myself who’s writing this post at this equivalent point in his Earth’s orbit (which might be billions of years in the past or future relative to my “now,” if such a thing could even be meaningfully measured), I wouldn’t really think of him as me, or his Earth as being my Earth.  So it wouldn’t really feel to me that those other fictional universes connected to my world’s history, and that would make them less meaningful.

Or would it?  I mean, just going in, I know these fictional universes don’t have the same physical laws as our universe, that the specific characters or alien races or whatever that exist in them don’t exist in our world.  So I know going in that they’re already separate realities from my own.  Their versions of Earth and its history may correspond almost exactly to ours, yet they’re still separate entities.  So maybe it’s no worse to think of my various written worlds (blog name drop!) as coexisting realms in an infinite multiverse than it is to think of them simply as independent fictional constructs.

And sure, sometimes I think it would be nice to have some sort of grand unified theory linking my universes together.  I already tend to think of “No Dominion” as being in a parallel quantum timeline of my Default universe, because it has no visible discrepancies in physics or cosmology and has a lot of similar technological and social developments; it’s just that some technologies develop decades too early to be compatible with my published or soon-to-be-published Default-universe fiction.  That won’t work for something like the Hub, though, since it has distinct differences in physical law.  And yeah, I admit I’ve tried to think of a way to fit my universes together into a unified multiverse, at least in passing.  I suppose the “infinite monkeys” idea could give me a means to do that.

But I don’t think I find it appealing, because it just multiplies the variables to such an insane degree.  If these universes are just infinitely separated samples of an infinitely expanding metacosmos, then that doesn’t really unify them in any way, does it?  They’re so far apart, so mutually unreachable, that the “connection” doesn’t really count as a connection at all.  (After all, given the underlying physical premise, there’s no realistic chance of any kind of wormhole link or inter-universe crossover anyway.)  It’s a trivial and useless result fictionally for the same reasons it is physically.  And if they’re specks in an infinite sea of universes, it makes them all feel kind of irrelevant anyway.  So why even bother?  It’s simpler just to treat them as distinct fictional constructs and not bother trying to unify them.  Besides, even if I know intellectually that the humanity and Earth and Milky Way of my fictional universes aren’t the same as my own, it’s more satisfying to pretend they are, to construct a satisfying illusion for the readers that they’re reading about an outgrowth of our own reality, than to pretend that they’re some totally separate duplicates in universes unreachably distant from ours.  No point going out of my way to create a premise that alienates me and my audience from the universes they’re reading about.  Granted, judging from some conversations I’ve had in the past, there are some people out there who wouldn’t have a problem with that.  But it doesn’t really work for me.