Sunday, December 6, 2015

Fermilab: Universe Looks a Little Bit Less Simulated

Fermilab tried to measure "quantum jitter", which would be expected if space and time are quantized, like energy. They did not find it.

This is another way of testing the holographic theory of the universe - which is itself an extension of the model that black holes' entropy can be measured entirely from their event horizons. Of course, the model could be wrong or the instrument might not be detecting it, but even from a primitive Bayesian standpoint this moves us away from quantized spacetime, a holographic universe, and our expectations of what we might find if we are in a simulation. The two problems with simulation arguments remain: in general what we mean by "simulation" is very poorly defined and not agreed upon, and there is the PEP (pointless epistemological problem) of saying that the simulators could always make us forget the results, or change that parameter somehow when we try to measure it. In which case, the simulation argument is about the most untestable thing there is, and if we can't ever in principle know, why are we bothering to discuss it? (By the way, the "simulators could change it" argument assumes we know something of the simulators' nature and that it/they are trying to deceive us.) (Below from SMBC of course.)

Sunday, September 13, 2015

Early Evolution of Intelligence More Likely Toward Galactic Center, Model Shows

As argued previously by other parties. From the abstract:
Our model also shows that [the likelihood of the emergence of intelligence] is increasing with time. [According to our model and fitting actual observations,] intelligent life emerged at approximately the present time at Earth's galactocentric radius, but a similar level of evolutionary opportunity was available in the inner Galaxy more than 2 Gyr ago. Our findings suggest that the inner Galaxy should logically be a prime target region for searches for extraterrestrial intelligence and that any civilizations that may have emerged there are potentially much older than our own.
1. Note that their point is that we should be searching there, NOT announcing our presence in any particular direction, especially core-ward. We should not do that if we seriously think there may be aliens in that direction, and there is a nonzero chance of any of them not being warm and fuzzy.

2. Furthermore, as we look toward the galactic center, we should be looking for Super-Earths (more surface area means more reaction volume to produce complex chemistry for biogenesis.)

Morrison Ian S. and Gowanlock Michael G. Extending Galactic Habitable Zone Modeling to Include the Emergence of Intelligent Life. Astrobiology. August 2015, 15(8): 683-696. doi:10.1089/ast.2014.1192.

Thursday, August 27, 2015

Greatest American Hero Ep. 22, "The Shock Will Kill You"

This was a great show. First of all it had Bill Katt (who should've been Luke Skywalker instead of Mark Hammill, because Bill Katt can, you know, ACT), it had Connie Sellecca, who was an early crush (of course before I found my true love Jane Badler). I remember that the alien eel thing scared the crap out of me, despite that they were obviously filming in such a way as to protect their budget. (Re-watching the nuclear attack scene in the 1980s made-for-TV The Day After similarly reactivated an old fight-or-flight response.)

Watching it again as an adult in comparison with modern "rules" for television genres, I found it interesting that the astronauts on the space shuttle unambiguously died. Today, that would be allowed in a serious prime-time show, but not a show with tongue-in-cheek overtones like this one had. I also liked that a random FBI agent comes into a California dam facility and demands an immediate water release so that a reservoir can be filled, and the guy listens to him! Of course we were much more loosey goosey in this state back before California turned into Arrakis; today the alien eel would have overrun the state!

Saturday, June 6, 2015

Computers Can Solve Long-standing Problems in Science and Create Theories

Yes, of course they can, because after all we create theories, and we're computers - but this is less trivial, because this is the first time silicon computers have created theories. There have already been exercises where data about the motions of bodies in the Solar System was put through automated inductive reasoning and reproduced the laws of gravitation. But this is different, because we already knew the answer when we re-constructed laws of gravitation. Software has now solved a problem in genetics that troubled the field for a century. (Original paper here.)

An objection might be "but does the computer understand the theory?" We humans often have a non-propositional, subjective sense that we understand something once we arrive at a model. But this sense is really like an emotion - that is, an internal experience that doesn't correlate to an object in the external world, and is separable from the reality it purports to relate to. That is to say: everyone has had the experience of feeling a "Eureka!" and then realizing they were wrong (and this feeling can range from seconds to years) - just as people with panic disorder genuinely feel terror as if they're going to die when they have a panic attack, without actually having their lives in jeopardy, in a kind of emotional hallucination. The computer is likely not experiencing a subjective eureka, but this has nothing to do with being correct.

Sunday, May 31, 2015

Spike Jonze's Her Is Not About the Future

There are a few comments online about Her that are fully on the mark about the content of the movie, yet miss the main goals I think Jonze was striving for. That people think enough about any work of fiction to be annoyed by it is usually a compliment. What Robin Hanson said was
The main character of Her pays a small amount to acquire an AI that is far more powerful than most human minds. And then he uses this AI mainly to chat with. He doesn’t have it do his job for him. He and all his friends continue to be well paid to do their jobs, which aren’t taken over by AIs...Soon after they all leave together for a place that ”it would be too hard to explain” where it is. This is somewhat like a story of a world where kids can buy nukes for $1 each at drug stores, and then a few kids use nukes to dig a fun cave to explore, after which all the world’s nukes are accidentally misplaced, end of story.
Yes, when you think about AI for a living, you can't help but notice these kinds of incongruities. For that matter I'm a casual fan of Roman history, and I still get annoyed when I see tailored clothing in Roman-period movies. Along these lines, for me the silliest thing in Her in terms of predicting the future might be the China-India merger news near the beginning of the movie. But if you can get past the window-dressing to remind you it's the future so the creator has some license to alter the setting to make his point, then you can also realize Her isn't about geopolitics and economics. The technology Jonze creates is only a means for him to focus on his main themes. First, even though Her is set in a science fiction near-future LA, it's a better depiction of LA than in most movies. For example: LA is on the coast, and it often has really nice clouds. (If you live or travel there, pay attention. It's not the vanilla neutral people-terrarium portrayed on our screens.) A simple touch like this, letting LA speak for itself, warms the heart and makes the city in the movie feel more similar to the world outside the theater. In fact, the movie almost made me homesick for Southern California, while I was living in Southern California! And another thing about LA: there is a natural world that the city hasn't obliterated. There are mountains. There are islands. There are things to do outside. There are restaurants very much like the ones the people in the movie go to. And speaking of restaurants, the differing ratio of white:non-white you can see among the characters' friends, as opposed to waitstaff, felt accurate too. (People in California don't like to talk about this discrepancy.)

But more importantly, Her is about how the nature of intimacy has changed in the modern age, with the gain turned up a little on the role of technology to help focus on this. There is the obvious point being made that the protagonist's job is to write heartfelt cards for others' intimates, and in so doing, interpose himself (by invitation, for commercial reasons) in the most tender moments between lovers and family members. Yet he himself spends most of his life alone in a dark apartment, his only close friends from back in college. There's always clearly a connection missing - made all the more obvious by the people around him during his commute - always physically alone - constantly talking to friends on their earpieces. His material comforts (which are many - witness the great view and the cool video game system) don't make up for his lack of connection. In all the material and surface aspects, this guy has a great life - even with that dumb mustache he manages to get a date with Olivia Wilde, which seems to go well, and then he whiffs. And finally, the most aggressive and uncomfortable experiment in intimacy is the "real" woman standing in for the virtual Samantha, yet another intimacy intermediary. I found this scene not at all salacious and indeed only slightly less uncomfortable than the threesome in the film version of The Handmaid's Tale. (Seriously, don't look it up.)

Thursday, February 19, 2015

Probability of Pre-Intelligent Life Seeding Between Solar Systems

That probability is increasing. Scholz's Star passed well within the outer edge of the Oort Cloud a mere 70,000 years ago. It's important to keep in mind that one theory for why we should expect to see life on Europa is that impacts on Earth must have thrown biological material into space, which must eventually impact on Europa. We shouldn't hold our breath for a whole giraffe to make it to Europa just yet, although it's worth recalling that the C. elegans worms (not giraffes, but at least metazoans!) on the Columbia survived re-entry and were found alive 3 weeks after impact (link here). While many outlets are covering the "Neanderthals must have seen this!" angle of the Scholz's Star near-miss, a more important take home is that if biological material can plausibly mix between bodies in the same solar system, it is not much less likely to mix between solar systems.

Scholz's Star is not unique. If this just happened 70,000 years ago, we can reasonably infer that this has happened frequently. 70,000 years is not a long time in astronomical terms. A number of known stars have come or will come within Oort-mixing distance in this 100,000 year period. In point of fact, the Stardust mission - which returned physical material from Wild-2 - showed based on isotope ratios that Wild-2 must have originated in a different solar system besides our own. We have classically thought about life moving between solar systems in terms of intelligent aliens building ships, but it may be more plausible to expect that something at the level of unicellular organisms or even simpler than that is what usually moves back and forth. The ideas is not new (probably Fred Hoyle articulated it first mid-20th century) but we now have more data to support the ideas as plausible.

Tuesday, February 10, 2015

Enceladus Ocean is Alkaline NaCl/Na2CO3 Solution

Similar to alkaline lakes on Earth; well within the pH range of extremophiles. Paper here.

Above: geysers at the south pole of Enceladus, credit Below: Soda Lake in the Carrizo Plain, California, USA, Earth, credit Wikipedia.

Sunday, February 8, 2015

Modeling Gamma Ray Bursts as Causes of Mass Extinctions

One of the explanations for the apparent rarity of life in the universe is the frightening gamma ray burst - perhaps life is astonishingly rare, and Earth has just been lucky to be in a narrow slice of space that for the last five billion years. But (almost?) everywhere else the planetary Petri dishes have undergone regular GRB autoclaving, or at least they got autoclaved before complex nervous systems develop. Putting numbers to this based on the observed distribution of GRBs, a recent paper modeled frequency and distribution of GRBs to estimate the chance over time of a GRB happening close enough to Earth to be life-damaging. Among their conclusions:

1) There's a 50% chance that a life-damaging GRB took place in the last 500 million years. Permian-Triassic extinction anyone?

2) The probability of a system being exposed to life-damaging GRBs goes up as you move toward the center of the galaxy. Many of our SETI efforts focused on our own galaxy have focused coreward, on the reasoning that there are more stars in that direction, therefore more chance of finding life. The reflex to this paper's model is to worry that we're looking in the wrong direction - but if you assume galaxy-colonizers, looking coreward may still be the best strategy - the GRB survivors on the galactic rim would be able to colonize inward.

Paper here.

Tuesday, February 3, 2015

Evidence for a Methane Source In Enceladus Oceans

Paper here. Hinges on the trapping of methane as clathrates, similar to subglacial lakes (i.e. Vostok) on Earth.