That’s So Second Millennium
Episode 018 - SCS Conference: Peter Koellner, Andrew Sicree

Episode 018 - SCS Conference: Peter Koellner, Andrew Sicree

July 30, 2018

As I've mentioned, we batch recorded the last four episodes about a month ago, and so we opened with a retrospective on the conference as a whole and its significance.

We moved on to discuss Peter Koellner. Koellner was the next talk and probably deserves his own podcast. I have gotten his lecture slides from him but won't have time to analyze them for a few weeks. The short version for now is that he gave us some perspective on Godel's theorem, a result in mathematical logic that many (including many agnostics like the physicist and mathematician Roger Penrose) have taken to imply that human thought must transcend any finite logical system that could be, say, programmed into a computer: in other words, the human mind is not a computer. Koellner argued, in large part from Godel's own writings, that what he actually proved is probably that EITHER human thought transcends the mechanical OR that there are mathematical truths that transcend mind. This is potentially a blow to a number of people who rely on the argument to prove our superiority to our own machines, but I myself find either conclusion to be exciting.

Andrew Sicree was next. He gave this tremendously gung-ho talk about Father Nick Steno, the 17th century member of the founder's club of geology (I think that's fair; Sicree basically called him the founder, singular). It was mostly fairly familiar stuff to me, some of which I have lectured on myself in classes in passing. He is still known today for Steno's Laws of stratigraphy (i.e., the relative ages of rocks):

Principle of Superposition

Principle of Original Horizontality

Principle of Inclusions

and in mineralogy he is remembered for the Law of Constant Interfacial Angles, basically the very dimmest beginning of crystallography. However, Sicree gave some time to other aspects of Nicolaus Steno's thought and also to his career as a layman and cleric. I only thought I was a Nick Steno fan before this talk. Andrew Sicree is the real deal.

Episode 017 - Aaron Schurger at SCSC: Fifty Years Without Free Will

Episode 017 - Aaron Schurger at SCSC: Fifty Years Without Free Will

July 23, 2018

It's a short one this week. We discuss the talk at the Society of Catholic Scientists Conference by Aaron Schurger with the delightfully provocative title "Fifty Years Without Free Will." (Those of you who are similiarly obsessive about grammar will appreciate my deep feeling of conflict about capitalizing the preposition "without" is not supposed to capitalize prepositions, yet it looks awful to have a seven letter word not capitalized. It's not capitalized in my notes, but it was in the program.)

Notes I took during the talk, which for this podcast pretty closely follows the drift of our conversation:

Distinction of the "neural decision to move"
Readiness potential with ~1 sec onset time
Libet et al 1983  Brain 106:623-42
    asked subjects to report when they decided to move
    happened ~3/4 sec after readiness potential, only ~1/4 sec before the movement
Taken by many as proof that "there is no free will"
Alternative interpretation: the "readiness potential" is random drift of neuron voltages
    under the weak imperative to move
Need to pay careful attention to experiment setup & analysis of data [Paul's comment today: *always*]
    Problems with only analyzing data time-locked to movement and extracted

Paul’s reread of the Divine Comedy

Paul’s reread of the Divine Comedy

July 17, 2018

The Divine ComedyThe Divine Comedy by Dante Alighieri
My rating: 4 of 5 stars

I have only ever read the Inferno and the Purgatorio in Ciardi's translation. I found the Paradiso in Mandelbaum's translation and could not make the transition between styles.

Someone got me this omnibus edition of Ciardi's translations, and I was excited to finally read the Paradiso in Ciardi's verse, but of course I let all sorts of lesser things get in the way and it sat on my shelf for a decade-ish.

I've finally gone back and read the whole thing through. I'm 25 years older and have learned to criticize the stuff I read rather than simply glide through it, mesmerized, like I used to do with all my favorite books when I was a youth. Not all positive. In any case, there are certainly patches where I suspect I would have found different words and a different tone.

Ciardi's introductions and notes were tremendously helpful to me when I was young. In fact, they were as important as the poem itself, if not more so, in the way reading the Divine Comedy introduced me to the whole medieval intellectual synthesis and the sense I have had ever since that there is a similar modern synthesis between science and Catholic faith, mediated by philosophy, waiting for us that would be far grander. So it is rather strange to me that now I almost feel they get in the way. I plan to read the book again and deliberately skip everything but the poem itself sometime in the next few years in preparation for a writing project I hope to dare to undertake.

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Episode 016 - Valerio Scarani at the Society of Catholic Scientists Conference 2018

Episode 016 - Valerio Scarani at the Society of Catholic Scientists Conference 2018

July 16, 2018

Dr. Scarani opened the talk by noting a paper he placed on about Aquinas and the sense that the universe would not be perfect without randomness.

He moved on to discuss randomness in two senses: Process Randomness, which implies that there is an observer unable to predict the output of the process; and Product Randomness, the lack of structure of a product, which turns out to equate with the need for a very long algorithm to replicate the product. Products are tested for randomness by a battery of statistical tests. He gave an equation embodying a mathematical definition of [product] randomness. Not being an information theorist, I had not seen it before.

He went on to note the difference between the randomness of classical physics, which is always about a lack of complete information about a system. If one had that information, the system under the classical assumption would be perfectly defined, and as we have noted a number of times, Einstein among others desperately wanted to get back to that deterministic paradigm. "The Old One doesn't throw dice."

The core of the talk was what Scarani called a "high school level" presentation of Bell's theorem. I would like to meet the high school student who could follow it at the speed at which he gave the talk, but probably could have unpacked it given a couple of hours to do so even at that age. Bell's theorem is one of those cunning little mathematical gems that seems to prove the unprovable, namely, to make a prediction about something going on in a process one by definition cannot see into. Bell sets up a statistic that, if there are hidden rules governing physics below the scale at which the uncertainty principle lets us see, must nevertheless in real experiments end up being less than 2. Since the 1980s a series of ever more careful experiments have been done, and the answers in the papers Scarani reviewed had answers between 2.4 and 2.7; the answer is never below 2. According to Bell's theorem, this means that there is a really random process going on down there, and not just random products.

At the end, as we discuss in the audio, Scarani ran down the list of remaining possibilities for understanding the quantum foundations of the universe:
- There is real randomness.
- "Superdeterminism." This depends on breaking an assumption of the Bell theorem, which is that the quantum process is being fed input that itself is not really random from the perspective of that process, which would seem to imply some sort of physics puppet master controlling the experimenter.
- The many worlds hypothesis, again something we have mentioned a number of times. I am still not buying that stock.
- The only allowable sort of hidden variables (the name Bohm is attached to the most commonly discussed of these) would require particles communicating with each other at infinite speed, "deliberately" trying to wreck the experiment, and with the interaction hidden in a way workers in the field have called "conspiratorially hidden." I.e., we would be living in a universe run by a sort of Cartesian evil deity.

On that theme, note that I blundered off into talking in a sort of Cartesian dualist fashion about the relationship between soul and body there after the 14 or 15 minute mark.

Episode 015 - Stephen Barr at the Society of Catholic Scientists Conference 2018

Episode 015 - Stephen Barr at the Society of Catholic Scientists Conference 2018

July 9, 2018

In today's episode we discuss Stephen Barr's talk at the SCS conference on June 9. His topic was the observer question in quantum mechanics. The observer problem is closely tied to the issue of probability and wavefunctions. We spend quite a while discussing what this problem is and how the question arises in the context of experiments like the famous two-slit experiment. The example of "Schrodinger's Cat" is an attempt to make this problem more understandable to the non-quantum mechanic. The cat is in some uncertain state, neither alive nor dead, until the observer opens the box and "collapses the wavefunction" to either a live cat or a dead one. In a two-slit experiment, a particle exists in some distribution of possible positions until an observer collapses the wavefunction and "forces" it to one tight range of locations (and for that matter momenta...).

This is very weird. Barr cited a long list of quantum theorists (von Neumann, London, Bauer, Wigner, Peierls, and others) who considered the problem and whether mind as such is crucial to whatever it is that does the measuring and observing to collapse quantum systems. Wavefunctions, with their consequent probability distributions, evolve according to Schrodinger's [or Dirac's?...a question I've had in the back of my mind many times...] equation with no internal mechanism to cause this collapse. Clearly two very unlike things interact to form quantum mechanics as we know it, as von Neumann stated explicitly (calling the observer / collapse phenomenon "process 1" and the wavefunction evolution "process 2").

It is clear that we can shift our mathematical formalism to incorporate any physical measurment device into the "system" and thus recognize it to be in the realm of wavefunction behavior. There is the "Wigner's friend" thought problem where even a human observer of an experimental setup can be placed in the "box" from the point of view of another human observer.

When we consider the observer problem from the point of view of a descriptive science (geology, astronomy, zoology, etc.) there is the immediate and rather alarming philosophical question: What was happening to, say, this star or tectonic plate or ancestral population of invertebrates before there was an observer to collapse the wavefunctions? Someone raised this question with Dr. Barr in the question and answer session after the talk. There is a phenomenon called "decoherence" (warning: that link is informative in places but far from the clearest read) which occurs for systems that are very open, interacting with their surroundings. Broadly speaking, the observable in question can trade uncertainty with its surrounding and settles down into a tighter range of possible states, simulating to some extent the effect of an observer collapsing the wavefunction. However, the two phenomena are not the same.

Episode 014 - Ed Feser’s Keynote at SCS

Episode 014 - Ed Feser’s Keynote at SCS

July 2, 2018

In this episode we begin a series of recaps and discussions of the issues brought up by individual lecturers at the Society of Catholic Scientists conference on June 9 and 10. We start with Ed Feser's keynote, "The Immateriality of the Mind."

Feser's objective was to highlight how our ability to be rational, and in particular for our thoughts to mean something unambiguous - even in the face of our inability to express ourselves in a completely unambiguous way in our spoken or written words - makes it difficult to maintain a purely materialist / physicalist view of human minds and therefore of the universe they inhabit.

At the outset he noted that rationality tends to occupy less attention in philosophy of mind and matter than two other properties, consciousness and intentionality, which seem widely taken as more difficult to explain by our contemporaries. For ancient and medieval philosophers, however, rationality was probably the clearest indication that the human mind is not some sort of solely physical mechanism.

Feser presents an argument via James Ross (Thought and the World) to try to bring this older consensus into the mainstream. It can be presented thus:

  • Formal thought processes can have an exact, unambiguous content.
  • Material signs and processes never have unambiguous content.
  • Formal thought processes must employ an element not dependent on materials signs and processes.

We discuss Feser's points and a few of our own in favor of the two premises: our inability to be sure of the content of arithmetical symbols used outside our own range of experience, the ambiguity of translating ancient languages like Linear A, and the absurdity of believing I can't ultimately know what I'm thinking about.

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