Monday, May 25, 2015

What does the Turing Test test?

Saw the movie Ex Machina. The outside shots, filmed in Valldalen, Norway, are are simply gorgeous. Good flick and provoked some ruminating (avoiding plot details).

There seems no a priori reason to suppose that machine intelligence cannot reach the point of passing the Turing test. A complex enough programed machine able to “learn” from extracting patterns from massive data and using them to interact with humans should be able to “exhibit intelligent behavior equivalent to, or indistinguishable from, that of a human.” One can imagine such a machine as pictured in the movie.

But what does the Turing test really test. An “artificial intelligence” might be able to interpret and respond to the full range of human behavior and simulate the same. It might be able to “read” a conscious human better than an actual human might by picking up on subtle physical manifestations (as stored in its memory). With a large enough data base behind it and a multitude of “learned” behaviors it might convince a human that it was indeed intelligent and even self-aware. But would it be? Would the ability to simulate human behavior completely enough to appear human actually be human or entail consciousness? If programed with a sub-routine causing it to seek to persist (i.e., resist termination), would it be a self seeking self-preservation? Would programing allowing it to read human emotions and respond “appropriately” with simulated emotion mean it actually felt such emotions?

Would a machine intelligence able to simulate human behavior and emotions actually be able to love, hate, feel empathy and act with an awareness of itself and, perhaps more importantly, of an Other? Or might there still be something missing?

Smoked a cigar on my favorite bench while considering all this and watched some ants going about their business. Ants are extremely complex biological machines acting and reacting within their environment with purpose and an overall drive to self-perpetuate (both as individuals and as a collective). They may be conscious even if not self aware. Or is a certain basic self-awareness something that goes with being alive? Would even a very complex machine ever be alive even if very “intelligent?”

My guess is that machine intelligence – even if very complex and advanced and equipped with a self-referential sub-program allowing algorithmic analysis of itself – would not be conscious or alive. Thus not capable of emotion and therefore what we might call coldly rational. Is this why Bill Gates, Stephen Hawking and others are concerned about AI?

Tuesday, May 19, 2015

Gravity, Mass and Time

Recently finished physicist Kip Thorne's The Science of Interstellar about his work to make the movie as scientifically grounded as possible. While written for the interested layperson, some of it was hard to follow. But it provided a lot of food for ruminating about the deep connections between gravity, mass, time and the speed of light.

At the speed of light, time stops. Anything with mass that reached the speed of light also achieves infinite mass. (This is one good reason to believe that nothing with mass can go that fast. Anything of infinite mass would need a great deal of thrust to keep going, indeed, an infinite amount.) Photons have no mass and thus they gain no mass. Anything – some ghost without a machine – traveling with that photon at 186,000 MPS would also be timeless and thus everywhere that photon will ever be all at once.

Time also stops with an infinite mass that is not going anywhere, at a black hole. Gravity slows time. At the event horizon of a black hole, spacetime is so warped that nothing can escape upwards – not time, not space, not matter, not light – but falls down into the black hole until it reaches the singularity at the “bottom.” While the black hole may have a certain mass – the mass left over from the collapse of the star that formed it – the singularity itself has the equivalent of infinite mass. Anyone watching a friend drop into a black hole would never see him or her actually fall all the way past the event horizon. From the outside, the friend would be seen moving ever slower. At some point, a second to the falling friend might be, for example, a billion years to the outside observer.

Not just black holes slow time. Anything with mass does, including earth. Einstein's theory of relativity predicts this. And indeed, time on the GPS satellites (orbiting over 16 thousand miles up) run some 45,900 nano seconds slower per day than clocks on earth. The stronger the gravity, the slower time goes compared to places of less gravity.

Mass warps spacetime and achieves that effect through gravity. We don't understand where gravity comes from and it does not fit into the Standard Theory of quantum physics. Relativity seems to describe the effects of gravity but neither meshes with the Standard Theory nor explains from whence gravity comes. String theory has been the Standard Model's framework to incorporate relativity as quantum gravity. To do so, it would require extra dimensions beyond the four we observe (three space and time). But recent experiments have found no supporting evidence for the simplest forms of such theories.

It may be that mass, gravity, and time are just givens. Gravity is something that slows time. At the speed of light, time stops. Our experience of time – our consciousness – seems related to the speed of light. Mass keeps us from exceeding the speed of light. Random?