My favorite television show is Lost. I’ve been obsessed with it for awhile and now, as if they needed to reel me in even more, they introduced a quantum consciousness sort of time travel storyline that hints at some of the things I’ve been discussing here, here, here, and here, as well as what’s been discussed over at The Observer Effect. It raises the question of whether or not superposition states consisting of two different times might possible exist and might this help explain seemingly inexplicable cases of déjà vu. While it is a radical notion for certain and I’m a serious skeptic of the paranormal, there is some precedent that, at least on the quantum level, this might be possible. In particular, the Leggett-Garg inequalities are Bell-like inequalities that provide correlations for time-separated events. In related work, I recently showed that the Cerf-Adami inequalities are a form of the second law of thermodynamics. Thus, as Ken Wharton agreed, it seems quantum mechanics violates the macroscopic form of the second law of thermodynamics. In short, while the universe appears time asymmetric on a macroscopic scale, it really is time symmetric, at least microscopically.
Archive for February, 2008
Some of my favorite drinks have some funky additives and, oddly enough, a few have ended up changing over the years as the FDA outlawed them. Here’s a look at three.
My favorite drink gets its distinctive taste (and aftertaste) from gentian root. According to Pliny the Eldar, “gentian” is an eponym of Gentius (180-168 BC), King of Illyria, who supposedly discovered its healing properties. In addition to Moxie, it appears in a number of alcoholic beverages including bitters.
Absinthe has generally been illegal in the United States and Europe until recently. The problem arose from the chemical thujone which is present in wormwood, the chief ingredient in absinthe. In the early 1990s some countries in Europe allowed it to be produced again after research showed that absinthe contains less thujone than originally thought and, in some cases, can be made authentically without at thujone present at all (while still using wormwood). Thujone-free absinthe is now manufactured in the US as well. Ernest Hemingway invented a terrific drink called “Death in the Afternoon” that was a mix of absinthe and champagne. I had a glass at lunch at the Morgan Library and Museum back in August. Mmmmm….
Since I grew up in Buffalo, which is only a few hours by car from Detroit, I grew up drinking a lot of Vernors (note the apostrophe was officially dropped years ago). Vernor’s is not exactly a ginger ale, per sé. It’s much more “gingery” than ginger ale and is often likened more to a ginger beer. In addition, it’s extremely carbonated and sometimes causes people to sneeze and cough when the drink it (it tends to tickle my nosehair). My dad is a huge fan and passed on his love of Vernors to me. From 1866 to 1991 it was sweetened with stevia. In 1991 the FDA outlawed it unless it was labeled as a dietary supplement. Vernors is now sweetened with high fructose corn syrup. Of course, it is apparently OK for Coca-Cola to go ahead and develop their own stevia-based sweetener, called Rebiana. Coke doesn’t own Vernors. Cadbury Schweppes owns Vernors and Cadbury Schweppes is a non-US Coke competitor. Anybody smell bullshit? I swear that if you want the US government – any of the three branches regardless of party affiliation – to care about you, you need to incorporate yourself and be loaded with $$$$.
Much of my thinking on certain topics is beginning to coalesce in interesting ways. I’ve been having an ongoing discussion with Ken Wharton about quantifying entanglement and time symmetry, helped along in my thinking by the very patient Rob Spekkens and Matt Leifer. Then, along comes Christopher Altman to tell me he’s actually been working on something along the lines of what I had floating around in my head (my thinking was partially spurred on by some of Kelly Neill’s posts). What have I got so far? Well, let’s take a look at the Chinese room argument again from a new perspective.
I think one of the main problems with the Chinese room argument is that it does not quantify understanding. What does it mean to understand something? Sprevak does not discuss this in his recent article. In a previous post, I argued that perhaps true AI would require quantum computers since real thinking likely involves superpositional thinking. But is that enough to provide understanding?
… and so is my wife. I’m talking about Facebook. In particular, we discovered a number of our good friends on here (who never told us they used it!) and this nifty mapping tool you can use to keep track of the places you’ve been. I, personally, think it’s an easier way to keep in touch with people than e-mail. Post on someone’s wall or your own and that’s that. Quite convenient, if you ask me.
At the behest of some of my friends, one of whom lives in Australia, I finally joined Facebook. I’ll admit I was apprehensive and felt I wasn’t perhaps the right generation, but I’ve come to discover many of my colleagues including a few who are closer to my parents’ age than mine are on there. But, now with Facebook, a blog, and SecondLife (which I’ve been on for over a year now), how am I ever going to keep track of all these people???
I’ve been thinking a lot lately about artificial intelligence and I have a hunch that what separates natural intelligence from the artificial variety is that the former includes what I might term “superpositional thinking” in that it simultaneously can consider multiple possibilities without necessarily being pre-programed to do so. As such, I think (and, again, it’s just a hunch at this point) that realistic AI will require quantum computers since, unlike classical computers, they allow for the existence of superposition states. But it’s just a hunch…
My lecture today in my Quantum Cryptography course brought together several recent threads on this blog. In particular, several interesting questions arose during the course of the lecture (I love having engaged and motivated students). The questions arose from our discussion of the BB84 protocol and the No-Cloning theorem. Essentially: 1. Do Alice and Bob need to be people or can they be machines? and 2. In what instances can Eve impersonate Bob (or Alice, for that matter)?
I love problems with funny names. In artificial intelligence circles, one such problem is called the Chinese room argument. Ostensibly it is an argument against so-called Strong Artificial Intelligence (Strong AI). Strong AI says that simply running a program imbues the system with “mentality,” one aspect of which is understanding. So, for example, I can read a story in Chinese but I won’t have the slightest understanding of it since I don’t know any Chinese. J.R. Searle gave the following argument against Strong AI (called the Chinese room argument).
Imagine a monolingual English speaker/reader in a room. The person has on a table an instruction booklet, pen, and paper. Notes written in Chinese are then passed into the room. The instruction booklet tells the person things like, “If you see Chinese character X on a slip of paper and Chinese character Y on another slip of paper, write Chinese character Z on your pad.” Chinese speakers outside the room label the slips going in ‘stories’ and ‘questions’ and the slips coming out ‘answers to questions.’ The instruction manual can be as sophisticated as you’d like. The question is, does our English speaker/reader – who only speaks and reads English – understand the Chinese, i.e. the details of the story and the associated questions and answers? Searle says no. To Searle, the room and the English speaker/reader is a computer and you can run as sophisticated a program as you’d like, but that it cannot understand Chinese regardless of the program. As such, Searle claims no program can be constitutive of understanding.
There have been critiques to Searle’s argument and the first one that comes to mind is adaptability. In a sense, for example, one might say that Akismet, the WordPress spam filter, “learns” what is spam and what is not and thus “understands” spam. Likewise, linguistic programs can “learn” language. Is there not an element of understanding inherent in learning?
In any case, a completely different set of arguments against Searle’s Chinese room has recently been published by Mark Sprevak in the British Journal for the Philosophy of Science. Amazingly enough, BJPS happens to have a considerable amount of freely available content and, hence, you can read all about Sprevak’s arguments here.
OK, I’m not entirely sure Rob Spekkens understood me, but I think I got it anyway. So, here’s how I guess I could explain it, then, to a student. You prepare a bag with two marbles – one black and the other red. You have someone reach in and randomly grab one. Before they look at it, you chuck the other one far, far away. If the person then looks at their marble and sees that it is red, then the other one must be black and is known instantaneously, even though there’s no violation of relativity in that sense. Conversely, any measurement made on the black marble is independent of whether or not we’ve looked at the red marble. The only difference is that, in quantum systems, the state isn’t necessarily pre-determined.
Taking Bob Griffiths’ consistent histories interpretation, the above (as well as true entanglement) could be rephrased in terms of events. Suppose the measurements of the marbles are events A and B respectively. While they are not causally linked (neither is in the past or future lightcone of the other), there is another event C such that A and B are both in its future lightcone (and it is in their past lightcones). Event C is what, in a sense, pre-determines A and B. So event C is the preparation. In our marble example, it is our act of first preparing the red and black marbles and then having someone choose one.
In any case, that is how a measurement can affect our knowledge – my making our measurement, we immediately know the state of the other particle without the need to measure it (assuming the two are entangled).