Escaping the bottle

Two years ago, I wrote a post about the work of Nick Bostrom (of Oxford University) and David Kipping (of Columbia University) regarding the unsettling possibility that we -- and by "we," I mean the entire observable universe -- might be a giant computer simulation.

There are a lot of other scientists who take this possibility seriously.  In fact, back in 2016 there was a fascinating panel discussion (well worth watching in its entirety), moderated by astrophysicist Neil deGrasse Tyson, considering the question.  Interestingly, Tyson -- who I consider to be a skeptic's skeptic -- was himself very accepting of the claim, and said at the end that if hard evidence is ever found that we are living in a simulation, he'll "be the only one in the room who's not surprised."

Other participants brought up some mind-boggling points.  The brilliant Swedish-American cosmologist Max Tegmark, of MIT, asked the question of why the fundamental rules of physics are mathematical.  He went on to point out that if you were a character inside a computer game (even a simple one), and you started to analyze the behavior of things in the game from within the game -- i.e., to do science -- you'd see the same thing.  Okay, in our universe the math is more complicated than the rules governing a computer game, but when you get down to the most basic levels, it still is just math.  "Everything is mathematical," he said.  "And if everything is mathematical, then it's programmable."

One of the most interesting approaches came from Zohreh Davoudi, also of MIT.  Davoudi is studying high-energy cosmic rays -- orders of magnitude more energetic than anything we can create in the lab -- as a way of probing the universe for what amount to glitches in the simulation.  It's analogous to the screen-door effect , a well-known phenomenon in visual displays, where (because there isn't sufficient resolution or computing power to give an infinitely smooth picture) if you zoom in too much, images pixellate.  The same thing, Davoudi says, could happen at extremely high energies; since you'd need an infinite amount of information to simulate behavior of particles on those scales, glitchiness in extreme conditions could be a hint we're inside a simulation.  "We're looking for evidence of cutting corners to make the simulation run with less demand on memory," she said.  "It's one way to test the claim empirically."

The reason this comes up is because of a recent paper by Roman Yampolskiy (of the University of Louisville) called, simply, "How to Hack the Simulation?"  Yampolskiy springboards from the arguments of Bostrom, Kipping, and others -- if you accept that it's possible, or even likely, that we're in a simulation, is there a way to hack our way out of it?

The open question, of course, is whether we should.  As I recall from The Matrix, the world inside the Matrix was a hell of a lot more pleasant than the apocalyptic hellscape outside it.

Be that as it may, Yampolskiy presents a detailed argument about whether it's even possible to hack ourselves out of a simulation (and answers the question "yes").  Not only does he, like Tegmark, use examples from computer games, but also describes an astonishing experiment I'd never heard of where the connectome (map of neural connections in the brain) of a roundworm, Caenorhabditis elegans, was uploaded into a robot body which then was able to navigate its environment exactly as the real, living worm did.  (The more I think about this experiment, the more freaked out I become.  Did the robotic worm know it was in a simulated body?)

Evaluating the strength of Yampolskiy's technical arguments is a bit beyond me, but to me where it becomes really interesting is when he gets into concrete suggestions of how we could get a glimpse of the world outside the simulation.  One method, he says, is get enormous numbers of people to do something identical and (presumably) easy to simulate, and then simultaneously all doing something different.  He writes:

If, say, 100 million of us do nothing (maybe by closing our eyes and meditating and thinking nothing), then the forecasting load-balancing algorithms will pack more and more of us in the same machine.  The next step is, then, for all of us to get very active very quickly (doing something that requires intense processing and I/O) all at the same time.  This has a chance to overload some machines, making them run short of resources, being unable to meet the computation/communication needed for the simulation.  Upon being overloaded, some basic checks will start to be dropped, and the system will be open for exploitation in this period...  The system may not be able to perform all those checks in an overloaded state...  We can... try to break causality.  Maybe by catching a ball before someone throws it to you.  Or we can try to attack this by playing with the timing, trying to make things asynchronous.

Of course, the problem here is that it's damn near impossible to get a hundred people to cooperate and follow directions, much less a hundred million.

Another suggestion is to increase the demand on the system by creating our own simulation -- a possibility Bostrom and Kipping considered, that we could be in a near-infinite nesting of universes within universes.  Yampolskiy says the problem is computing power; even if we're positing a simulator way smarter than we are, there's a limit, and we might be able to exploit that:

The most obvious strategy would be to try to cause the equivalent of a stack overflow—asking for more space in the active memory of a program than is available—by creating an infinitely, or at least excessively, recursive process.  And the way to do that would be to build our own simulated realities, designed so that within those virtual worlds are entities creating their version of a simulated reality, which is in turn doing the same, and so on all the way down the rabbit hole.  If all of this worked, the universe as we know it might crash, revealing itself as a mirage just as we winked out of existence.

In which case the triumph of being right would be cancelled out rather spectacularly by the fact that we'd immediately afterward cease to exist.

The whole question is as fascinating as it is unsettling, and Yampolskiy's analysis is at least is a start (along with more technical approaches like Davoudi's cosmic ray experiments) toward putting this on firmer scientific ground.  Until we can do that, I tend to agree with theoretical physicist James Sylvester Gates, of the University of Maryland, who criticizes the simulator argument as not being science at all.  "The simulator hypothesis is equivalent to God," Gates said.  "At its heart, it is a theological argument -- that there's a programmer who lives outside our universe and is controlling things here from out there.  The fact is, if the simulator's universe is inaccessible to us, it puts the claim outside the realm of science entirely."

So despite Bostrom and Kipping's mathematical argument and Tyson's statement that he won't be surprised to find evidence, I'm still dubious -- not because I don't think it's possible we're in a simulation, but because I don't believe that it's going to turn out to be testable.  I doubt very much that Mario knows he's a two-dimensional image on a computer monitor, for example; even though he actually is, I don't see how he could figure that out from inside the program.  (That particular problem was dealt with in brilliant fashion in the Star Trek: The Next Generation episode "Ship in a Bottle" -- where in the end even the brilliant Professor Moriarty never did figure out that he was still trapped on the Holodeck.)

So those are our unsettling thoughts for the day.  Me, I have to wonder why, if we are in a simulation, the Great Simulators chose to make this place so freakin' weird.  Maybe it's just for the entertainment value.  As Max Tegmark put it, "If you're unsure at the end of the day if you live in a simulation, go out there and live really interesting lives and do unexpected things so the simulators don't get bored and shut you down." 

Which seems like good advice whether we're in a simulation or not.

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Worlds without end

Earlier this week, I dealt with the rather unsettling idea that when AI software capabilities improve just a little more, we may be able to simulate someone so effectively that their interactions with us will be nearly identical to the real thing.  At that point, we may have to redefine what death means -- if someone's physical body has died, but their personality lives on, emulated within a computer, are they really gone?

Well, according to a couple of recent papers, the rabbit hole may go a hell of a lot deeper than that.

Let's start with Russian self-styled "transhumanist" Alexey Turchin.  Turchin has suggested that in order to build a convincing simulated reality, we need not only much more sophisticated hardware and software, we need a much larger energy source to run it than is now available.  Emulating one person, semi-convincingly, with an obviously fake animated avatar, doesn't take much; as we saw in my earlier post, we can more or less already do that.

But to emulate millions of people, so well that they really are indistinguishable from the people they're copied from, is a great deal harder.  Turchin proposes that one way to harvest that kind of energy is to create a "Dyson sphere" around the Sun, effectively capturing all of that valuable light and heat that otherwise is simply radiated into space.

Now, I must say that the whole Dyson sphere idea isn't what grabbed me about Turchin's paper, as wonderful as the concept is in science fiction (Star Trek aficionados will no doubt recall the TNG episode "Relics," in which the Enterprise almost got trapped inside one permanently).  The technological issues presented by building a Dyson sphere that is stable seem to me to be nearly insurmountable.  What raised my eyebrows was his claim that once we've achieved a sufficient level of software and hardware sophistication -- wherever we get the energy to run it -- the beings (can you call them that?) within the simulation would proceed to interact with each other as if it were a real world.

And might not even know they were within a simulation.

"If a copy is sufficiently similar to its original to the extent that we are unable to distinguish one from the other," Turchin asks, "is the copy equal to the original?"

If that's not bad enough, there's the even more unsettling idea that not only is it possible we could eventually emulate ourselves within a computer, it's possible that it's already been done.

And we're it.

Work by Nick Bostrom (of the University of Oxford) and David Kipping (of Columbia University) has looked at the question from a statistical standpoint.  Way back in 2003, Bostrom considered the issue a trilemma.  There are three possibilities, he says:

• Intelligent species always go extinct before they become technologically capable of creating simulated realities that sophisticated.
• Intelligent species don't necessarily go extinct, but even when they reach the state where they'd be technologically capable of it, none of them become interested in simulating realities.
• Intelligent species eventually become able to simulate reality, and go ahead and do it.

Kipping recently extended Bostrom's analysis using Bayesian statistical techniques.  The details of the mathematics are a bit beyond my ken, but the gist of it is to consider what it would be like if choice #3 has even a small possibility of being true.  Let's say some intelligent civilizations eventually become capable of creating simulations of reality.  Within that reality, the denizens themselves evolve -- we're talking about AI that is capable of learning, here -- and some of them eventually become capable of simulating their reality with a reality-within-a-reality.

Kipping calls such a universe "multiparous" -- meaning "giving birth to many."  Because as soon as this ball gets rolling, it will inevitably give rise to a nearly infinite number of nested universes.  Some of them will fall apart, or their sentient species will go extinct, just as (on a far simpler level) your character in a computer game can die and disappear from the "world" it lives in.  But as long as some of them survive, the recursive process continues indefinitely, generating an unlimited number of matryoshka-doll universes, one inside the other.

[Image licensed under the Creative Commons Stephen Edmonds from Melbourne, Australia, Matryoshka dolls (3671820040) (2), CC BY-SA 2.0]

Then Kipping asks the question that blows my mind: if this is true, then what is the chance of our being in the one and only "base" (i.e. original) universe, as opposed to one of the uncounted trillions of copies?

Very close to zero.

"If humans create a simulation with conscious beings inside it, such an event would change the chances that we previously assigned to the physical hypothesis," Kipping said.  "You can just exclude that [hypothesis] right off the bat.  Then you are only left with the simulation hypothesis.  The day we invent that technology, it flips the odds from a little bit better than 50–50 that we are real to almost certainly we are not real, according to these calculations.  It’d be a very strange celebration of our genius that day."

The whole thing reminded me of a conversation in my novel Sephirot between the main character, Duncan Kyle, and the fascinating and enigmatic Sphinx, that occurs near the end of the book:

"How much of what I experienced was real?" Duncan asked.

"This point really bothers you, doesn't it?"

"Of course. It's kind of critical, you know?"

"Why?" Her basso profundo voice dropped even lower, making his innards vibrate.  "Everyone else goes about their lives without worrying much about it."

"Even so, I'd like to know."

She considered for a moment.  "I could answer you, but I think you're asking the wrong question."

"What question should I be asking?"

"Well, if you're wondering whether what you're seeing is real or not, the first thing to establish is whether or not you are real.  Because if you're not real, then it rather makes everyone else's reality status a moot point, don't you think?"

He opened his mouth, stared at her for a moment, and then closed it again.

"Surely you have some kind of clever response meant to dismiss what I have said entirely," she said.  "You can't come this far, meeting me again after such a long journey, only to find out you've run out of words."

"I'm not sure what to say."

The Sphinx gave a snort, and a shower of rock dust floated down onto his head and shoulders.  "Well, say something.  I mean, I'm not going anywhere, but at some point you'll undoubtedly want to."

"Okay, let's start with this.  How can I not be real?  That question doesn't even make sense.  If I'm not real, then who is asking the question?"

"And you say you're not a philosopher," the Sphinx said, her voice shuddering a little with a deep laugh.

"No, but really.  Answer my question."

"I cannot answer it, because you don't really know what you're asking.  You looked into the mirrors of Da'at, and saw reflections of yourself, over and over, finally vanishing into the glass, yes?  Millions of Duncan Kyles, all looking this way and that, each one complete and whole and wearing the charming befuddled expression you excel at."

"Yes."

"Had you asked one of those reflections, 'Which is the real Duncan Kyle, and which the copies?' what do you think he would have said?"

"I see what you're saying.  But still… all of the reflections, even if they'd insisted that they were the real one, they'd have been wrong.  I'm the original, they're the copies."

"You're so sure?... A man who cannot prove that he isn't a reflection of a reflection, who doesn't know whether he is flesh and blood or a character in someone else's tale, sets himself up to determine what is real."  She chuckled.  "That's rich."

So yeah.  When I wrote that, I wasn't ready for it to be turned on me personally.

Anyhow, that's our unsettling science/philosophy for this morning.  Right now it's probably better to go along with Duncan's attitude of "I sure feel real to me," and get on with life.  But if perchance I am in a simulation, I'd like to appeal to whoever's running it to let me sleep better at night.

And allow me to add that the analysis by Bostrom and Kipping is not helping much.

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Last week's Skeptophilia book-of-the-week was about the ethical issues raised by gene modification; this week's is about the person who made CRISPR technology possible -- Nobel laureate Jennifer Doudna.

In The Code Breaker: Jennifer Doudna, Gene Editing, and the Future of the Human Race, author Walter Isaacson describes the discovery of how the bacterial enzyme complex called CRISPR-Cas9 can be used to edit genes of other species with pinpoint precision.  Doudna herself has been fascinated with scientific inquiry in general, and genetics in particular, since her father gave her a copy of The Double Helix and she was caught up in what Richard Feynman called "the joy of finding things out."  The story of how she and fellow laureate Emmanuelle Charpentier developed the technique that promises to revolutionize our ability to treat genetic disorders is a fascinating exploration of the drive to understand -- and a cautionary note about the responsibility of scientists to do their utmost to make certain their research is used ethically and responsibly.

If you like biographies, are interested in genetics, or both, check out The Code Breaker, and find out how far we've come into the science-fiction world of curing genetic disease, altering DNA, and creating "designer children," and keep in mind that whatever happens, this is only the beginning.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

In the dark

To further investigate our general topic of people giving woo-woo explanations to damn near everything, today we investigate: The Dark.

First, a brief physics lesson.

Things are generally called "dark" for one of two reasons.  First, there are objects whose chemical makeup results in their absorbing most of the light that falls on them.  Second, there are things that don't interact with light much at all, so they neither absorb nor reflect light -- light passes right through them.  An example of the first would be a charcoal briquet.  An example of the second would be interstellar space, which is sort of dark-by-default.

This whole thing comes up because of the discovery of an extrasolar planet with the mellifluous name TrES-2b.  TrES-2b orbits the even more charmingly named GSC 03549-02811, a star about 718 light years away.   More interestingly, it has the distinction of being the darkest extrasolar planet yet discovered.  David Kipping, of the Harvard-Smithsonian Center for Astrophysics, stated, "TrES-2b is considerably less reflective than black acrylic paint, so it is truly an alien world."

Artist's conception of TrES-2b [image courtesy of of NASA/JPL-Caltech and the Wikimedia Commons]

That was all it took.  Whereas my reaction was, "Huh!  A Jupiter-sized charcoal briquet!  That's kinda cool," the woo-woos just couldn't resist wooing all over this story.  We now have the following speculations, all from websites owned by people who probably shouldn't be allowed outside unsupervised:

• TrES-2b is made of antimatter, and we shouldn't go there because it would blow up.  We know it's antimatter because antimatter has the opposite properties to matter, so it's dark. 
• TrES-2b is made of "dark matter," and yes, they're not just talking about stuff that's black, they're talking about the physicists' "dark matter," about which I'll have more to say in a moment. 
• TrES-2b is dark because it's being hidden by aliens who are currently on their way to Earth to take over.  Lucky for us we spotted it in time! 
• TrES-2b is hell.  No, I'm not making this up. 

Well. You just opened the floodgates, now didn't you, Dr. Kipping?

The first two explanations left me with a giant bruise on my forehead from doing a faceplant while reading.  At the risk of insulting my readers' intelligence, let me just say quickly that (1) antimatter's "opposite properties" have nothing to do with regular matter being light and antimatter being dark, because if it did, the next time a kindergartner pulled a black crayon out of the box, he would explode in a burst of gamma rays; and (2) "dark matter" is called "dark" because of the second reason, that it doesn't interact with much of anything, including light, so the idea of a planet made of it is a little ridiculous, and in any case physicists haven't even proved that it exists, so if some astrophysicist found a whole freakin' planet made of it it would KIND OF MAKE HEADLINES ALL OVER THE FUCKING WORLD, YOU KNOW?

Sorry for getting carried away, there.  But I will reiterate something I have said more than once, in this blog; if you're going to start blathering on about science, for cryin' in the sink at least get the science right.  Even the least scientific woo-woo out there can read the Wikipedia page for "Dark Matter," for example, wherein we find in the first paragraph the sentence, "The name refers to the fact that it does not emit or interact with electromagnetic radiation, such as light, and is thus invisible to the entire electromagnetic spectrum."  (Italics mine, and put in so that any of the aforementioned woo-woos who are reading this post will focus on the important part.)

And I won't even address the "secret alien base" and "hell" theories regarding TrES-2b, except to say that it should come as a relief that the evil aliens or Satan (depending on which version you went for) are safely 718 light years away.  To put this in perspective, this means that if they were heading here in the fastest spacecraft humans have ever created, Voyager 1, which travels at about 16 kilometers per second,  it would still take them eleven million years to get here.

In any case, I guess it's all a matter of how you view what's around you.  I find the universe, and therefore science, endlessly fascinating, because what scientists have uncovered is weird, wonderful, and counterintuitive.  I don't need to start attaching all sorts of anti-scientific bunk to their discoveries -- nature is cool enough as it is.

Okay, thus endeth today's rant.  I will simply end with an admonishment to be careful next time you barbeque.  I hear those charcoal briquets can be made of antimatter, which could make your next cook-out a dicey affair.  You might want to wear gloves while you handle them.  Better safe than sorry!

Cloaking device activated

New from the "Don't We Have Worse Things To Worry About?' department, we have two astronomers from Columbia University proposing that we use a laser-based device to cloak our planet from being spotted by hostile aliens.

[image courtesy of the Wikimedia Commons]

In a paper in the Monthly Notices of the Royal Astronomical Society, David Kipping and Alex Teachey suggest that it might be time to consider shielding our planet from unfriendly eyes.

"About ten years ago, it was proposed that aliens might choose to signal their presence to us not through radio waves, but by building megastructures, which would transit their star and create very weird and artificial-looking transits," Kipping said, bringing to mind the odd luminance drops discovered last year in "Tabby's Star," an anomaly that has yet to be satisfactorily explained.

Scientific luminaries as prominent as Stephen Hawking have suggested that however exciting the discovery of extraterrestrial intelligence would be, it might not be so great if the aliens came for a visit.  "We don't know much about aliens, but we know about humans," Hawking said.  "If you look at history, contact between humans and less intelligent organisms have often been disastrous from their point of view, and encounters between civilizations with advanced versus primitive technologies have gone badly for the less advanced.  A civilization reading one of our messages could be billions of years ahead of us.  If so, they will be vastly more powerful, and may not see us as any more valuable than we see bacteria."

Put even more succinctly by none other than Dave Barry, "It's all well and good for Carl Sagan to talk about how neat it would be to get in touch with aliens, but I bet he'd change his mind pronto if they actually started oozing under his front door.  I bet he'd be whapping at them with his golf clubs just like the rest of us."

Kipping says that the idea of cloaking the Earth is feasible, and wouldn't be very expensive, costing around the same in energy as seventy typical homes.  "We realized that because lasers are narrow directed beams, it was quite feasible to produce artificial transits," Kipping said.  "We then took this a step further and had the idea that one could use such a laser system to completely cloak the Earth's transit."

So that sounds okay.  But this does bring up two troubling points.

The first is that if there are intelligent life forms out there looking in our direction, they already know we're here.  Starting in the 1950s, we've been beaming radio waves into space carrying our television shows, an idea that has spawned movies as different as Starman and Galaxy Quest.  Any aliens intercepting our transmissions started with such feats of brilliance as Gilligan's Island, The Beverly Hillbillies, and (heaven help us all) Lost in Space, which means they have probably already decided that Earth's inhabitants are a bunch of complete morons.  It wouldn't surprise me to find out that we've already been the subject of a documentary on another planet entitled The Derpuloids of Dumbass-3.

So there's the problem of too little, too late.  But the more serious issue is that maybe instead of worrying about the arrival of hostile aliens, we should attend to more pressing problems.  To wit: climate change (and the fact that our leaders are largely sitting around with their fingers in their ears saying, "la-la-la-la-la, not listening" whenever a climate scientist brings up the topic).  Environmental devastation on a mammoth scale.  The increase in earthquakes directly caused by hydrofracking.  The fact that the American presidential election is increasingly looking like it will boil down to, "Which disease would you like?  Leprosy or syphilis?"

I know that installing a Romulan Cloaking Device on the Earth doesn't preclude our attending to some of these other issues, but I do worry about our attention being trained on the wrong things.  If you consider overall risk, I think that the collapse of the ice shelves, and the flooding of every coastal city on Earth -- now considered virtually inevitable -- is a little more critical than taking measures to keep away the Cardassians.

So anyway.  I'm all for SETI (the Search for Extraterrestrial Intelligence).  I would love nothing better than to have concrete proof that we're not alone in the universe.  But considering the vast distances we're talking about -- keep in mind that light from the nearest star takes a little over four years to get here -- I'm thinking we're safe.  Even if the aliens watched episodes of Green Acres, decided that humanity didn't deserve to live, and took off in their spaceship with planet-destroying missiles, I think we won't have anything to fret about for a long time yet.