Agent Plus Environment

Billions and trillions

Step by slow, supercomputed step, we approach singularity.

This step: Two massively parallel cortical simulations, run at the Lawrence Livermore National Labs by Rajagopal Ananthanarayanan, Steven Esser, and Dharmendra Modha of the IBM Almaden Research Center, and Horst Simon of the aforementioned labs–these are the guys who previously simulated at the scale of mouse and rat cortices. They used a Blue Gene supercomputer (with a whopping 456 CPUs and 144 TB of main memory–just wait, ten years from now I’ll look back on this sentence and laugh at how little computing power and memory that is). The first, and larger, simulation included 1.6 billion neurons and 8.87 trillion synapses. Human brains still dwarf these numbers: roughly 20 billion neurons and 200 trillion synapses. But it’s a cat-sized step with the complexity and scale of a feline brain.

The first simulation used experimentally-measured gray matter thalamocortical connectivity from a cat’s visual cortex–the simulations neurons were connected in a biologically plausible fashion. Phenomenological spiking neurons, individual learning synapses, axonal delays, and dynamic synaptic channels were all included in the software. The second simulation, with 900 million neurons and 9 trillion synapses, had probabilistic connectivity.

Speed-wise, the researchers report that their simulation runs 2-3 orders of magnitude slower than real-time, when compared to a human cortex. With near perfect weak scaling (doubling the memory resource doubles the model size that can be simulated), human-scale models may be just around the corner… well, relatively speaking; the researchers predict it’ll happen in less than ten years. Just as soon as there’s a supercomputer super enough.

The research paper is also available at researcher Dharmendra Modha’s blog [PDF].

But bigger isn’t necessarily better

We may have to wait ten years for human-scale simulations, but we may not need a human-scale platform to be able to build intelligent AI. Researchers at Queen Mary, University of London suggest that bigger may not necessarily be better, when it comes to brains. A lot of complexity can be found even in tiny insect brains. Maybe it’ll be a swarm of honeybee robots that takes over the world!

The complexity of models

For a time, I was convinced that every model out there would not be an adequate model of what a human brain could do because every model out there had to simplify, and thus, that no model or computer software would ever be able truly intelligent until we had the computing power to make an electronic human. I knew there was value to models, but deep down, I retained the conviction that no model, no simulation, no AI would ever manage the same level of complexity or intelligence as a human without being, simply put, a human.

Fortunately, I was relieved of this notion around the same time I started taking Cognitive Science classes: Humans aren’t the only intelligent creatures, the point of a model is not to create the thing you are modeling, all models simplify some aspect (it’s just a matter of choosing which aspects are most important to get exactly right). The world may be its own best representation, as Rodney Brooks so aptly said, but that should not preclude us from simplifying the world to better understand how it works, nor should that, in return, prevent us from trying to simulate ourselves in software.

I, for one, am looking forward to watching the intelligent honeybee robots and the supercomputer human brains band together to overthrow the government.

Beautiful and good to eat

Deep down, maybe we all know we are, every one of us, a unique snowflake. But a lot of people, they don’t want it to be true. They want all the snowflakes to melt together into one big puddle. They want to be able to share their subjective view of the world with everyone else. They want to be able to look at a sunset and know that what it’s like for me to see the sunset is the same as what it’s like for you to see the sunset.

Hey, we all want things we can’t have. And in this case, science says no! Here’s a piece of wisdom from David Brin’s sci-fi novel Kiln People:

“We may use similar terms to describe a sunset. Our subjective worlds often correspond, correlate, and map onto each other. That makes cooperation and relationships possible, even complex civilization. Yet a person’s actual sensations and feelings remain forever unique. Because a brain isn’t a computer and neurons aren’t transistors.

It’s why telepathy can’t happen. We are, each of us, singular and forever alien…”

The amazing thing about people is that this fact doesn’t deter us. We keep trying to share our sensations and feelings with each other. As Virginia Woolf writes in her book Orlando:

For it is a curious fact that though human beings have such imperfect means of communication, that they can only say “good to eat” when they mean “beautiful” and the other way about, they will yet endure ridicule and misunderstanding rather than keep any experience to themselves.

To be known and understood

Maybe we’re just stubborn. Maybe we’re clinging to a shred of hope that science is wrong and someday, instead of just overlapping with pieces of each other, we’ll be able to know what it’s like to experience the sunset the way someone else does. Here’s a passage from a favorite book of mine, Man Walks Into a Room by Nicole Krauss:

“When you’re young, you think it’s going to be solved by love. But it never is. Being close—as close as you can get—to another person only makes clear the impassable distance between you. . . .

“But see, the incredible thing about people is that we forgot,” Ray continued. “Time passes and somehow the hope creeps back and sooner or later someone else comes along and we think this is the one. And the whole thing starts all over again. We got through our lives like that, and either we just accept the lesser relationship—it may not be total understanding, but it’s pretty good—or we keep trying for that perfect union, trying and failing, leaving behind us a trail of broken hearts, our own included. In the end, we die as alone as we were born, having struggled to understand others, to make ourselves understood, but having failed in what we once imagined was possible.”

“People really want that, what did you say, merging souls? Total union?” [Samson]

“Yes. Or at least they think they do. Mostly what they want, I think, is to feel known.”

What do you think? Is the ultimate human goal to feel known and understood? And if that’s the case, is the illusion of feeling known enough to compensate for never truly being able to share one’s experiences with anyone else?

Snapshot: Classroom

Tap tap tap. That’s your pencil hitting the edge of your desk, one rhythmic note at a time. The wood of the pencil has a little indent now from all the tapping (unless you use a mechanical pencil), but at least you’re still awake. The kid next to you has been slumped over his notebook for the past half hour. You’re pretty sure he’s snoring. He has every reason to be, though; the professor has a fantastically monotone voice. Bullet point after bullet point, slide after slide. It’s not like you have to pay attention, either–everything the professor is saying is in the lecture notes handed out at the start of class. But you feel obligated to try to stay awake.

Death by Power Point

Is this at all familiar? Most of us, at some point or another, have experienced the ultimate Boring Lecture: A droning, not-quite-loud-enough voice, reading sentences one by one off a set of elaborate PowerPoint slides. The slides look pretty, sure, but fancy formatting can’t overcome the serious lack of anything remotely engaging.

Fortunately, most lecturers aren’t that bad. But as my friend Carolyn points out, a lot of professors still rely too heavily on PowerPoint. The primary instruction, she says, needs to come from the professors, not from the text slopped across their slides.

And it’s true. A lecture is a performance, and Hubert Knoblauch’s (2008) analysis of PowerPoint presentations suggests that the use of PowerPoint serves to amplify the performance aspect. Slides should complement rather than replace the presenter’s speech. They should be used to emphasize points and help explain difficult concepts with diagrams and photos; after all, a separate sheet of lecture notes with all the text of the bullet points can be handed out later. This may sound obvious, but in practice, most of us conform to convention of cluttering up our slides with too many words and too much visual noise.

Keep it simple, stupid

How do we fix this problem and avoid death by PowerPoint? Garr Reynolds recommends a highly minimalist approach (he’s got a handout[pdf] summarizing his suggestions). Instead of lists and summaries, put just a few key words boldly in the middle of the slide. Use large images and diagrams. Turn off the projector entirely when you happen to digress from the slides. Remove excess logos and irrelevant graphics–they’re just visual noise that detract from your message.

It may take some effort to get the hang of the minimalist presentation (I certainly haven’t gotten it down, though I try), and it will certainly take some guts to be the nonconformist who doesn’t use bullet points. One of my professors at the University of Sydney told a story about a student who went minimalist and was marked down as a result: It wasn’t a proper presentation! (The audience, however, said it was one of the best presentations they had seen in a long time.)

A place for everything

That said, bullet points occasionally have their place: e.g., when the goal is to memorize facts (Kinchin & Cabot, 2007). But if the aim is to make links between concepts and gain a deeper understanding of the subject, other methods of presenting information may fare better.

I’ll open up the floor. What tips and tricks do you keep up your sleeve for making a PowerPoint engaging? Do you adhere to minimalism? Obviously, it’s not all about the slides–it’s also about delivery. Feel free to share thoughts on that, too.

References:
Knoblauch, H. (2008). The Performance of Knowledge: Pointing and Knowledge in Powerpoint Presentations. Cultural Sociology, 2(75):75-97. [PDF]

Kinchin, I., & Cabot, L. (2007). Using concept mapping principles in PowerPoint. Eur J Dent Educ, 11: 194-199. [PDF].

We’re in the dark

Recent measurements of the cosmic microwave background (radiation leftover from the universe’s early hot and dense state) support the hypothesis that dark matter and dark energy make up 95% of everything in existence.

But what’s the matter?

Isn’t it fascinating and mind-boggling that we have almost no idea what the majority of the stuff in our universe is? There are dark matter and dark energy are not rather than explain what these mysterious stuffs are. E.g., dark matter is not just dark clouds of normal matter (called baryonic matter); it is not antimatter; it is not huge black holes. But it is 25% of the universe.

Current research on dark energy hasn’t faired better: Is it a property of space, as suggested by Einstein’s cosmological constant? Perhaps it’s a result of the quantum mechanics of space; maybe it’s a new kind of energy field. It’s also possible that Einstein was wrong. It wouldn’t be the first time a seemingly brilliant solution, explaining everything known at the time, was later replaced. Think “ether.” Think “animal spirits.” Think “caloric fluid.” That said, there’s nothing better to replace it yet. At least this time we’re acknowledging the fact that the names “dark energy” and “dark matter” refer to stuff we don’t yet understand.

The quest goes on

The Joint Dark Energy Mission, a space probe designed to study dark energy, has been in the works for a while now. The mission is currently in a tight spot as NASA, the Department of Energy, and the European Space Agency tussle over who’s in charge of which parts of the probe and who’s paying for what. Don’t you love international politics? A lot of people, such as the folks at the Cosmic Variance blog are up in arms about the disagreements–can’t we all just get along and do science?

“I got these pictures off the Internet.”

This is not a sentence that should ever be uttered when one is giving a presentation, yet last week, a fellow student said those exact words.

“The Internet” is not a reference.

Chapters of books, articles in journals, and individual web pages can be references. The Internet, instead, is like a library: A place to find references. You don’t cite your library in presentations.

Perhaps some of the confusion arises because all the content on the Internet is accessed through the same program (your web browser of choice). Because it is all seen in the same window on your monitor screen, it must all originate in the same place, right? Intelligent people know better, yet it is still easy to fall into the trap of assuming that images in particular and digital media in general belong not to one author, but to the vast, amorphous sea of information floating around cyberspace. If it shows up in a Google search, it’s free for the taking, right?

I’m not going to lecture you on copyright laws or on how to properly cite images. But for the curious, here is a long and detailed explanation of copyright and digital images. If that’s too long, pop a couple words such as “digital images” and “copyright” into Google and I’m sure you’ll find a summary. I’ll also recommend Chris Chesher’s article on blogs and the crisis of authorship, a related but not identical topic.

References:
The Internet. Accessed November 3, 2009.