Monthly Archives: September 2021

September 6, 2021

BB #78: Relational Theories

I read Three Roads to Quantum Gravity (2001), by Lee Smolin, a theoretical physicist whose thoughtful style I’ve always appreciated. I don’t always agree with his ideas, though. This book is about Loop Quantum Gravity, in which Smolin has invested considerable effort, and that idea I’m utterly neutral on. It does seem to make more sense than string theory.

One notion I have a lot of trouble swallowing (like a cup of coffee with eight lumps of sugar) is the relational view. (As a philosophy, relationism. Al stayed home.) It’s a fundamental aspect of LQG.

But I (and apparently Kant agrees) think Leibniz was wrong.

7 Comments | tags: Lee Smolin, Loop Quantum Gravity, quantum gravity | posted in Books, Brain Bubble

September 6, 2021

BB #77: Smooth Spacetime

By Wyrd Smythe

I read Three Roads to Quantum Gravity (2001), by Lee Smolin, a theoretical physicist whose thinking I’ve appreciated since I read his 2006 book, The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next.

Three Roads, as the title suggests, is about the efforts to reconcile quantum mechanics and General Relativity, our two best physical theories. String theory is one road, Loop Quantum Gravity (Smolin’s preferred approach) is another. The third road is complete theory reconstruction (such as discussed by Philip Ball in his book Beyond Weird).

None of that is the subject of this post.

2 Comments | tags: General Relativity, Lee Smolin, Loop Quantum Gravity, quantum gravity | posted in Books, Brain Bubble

September 6, 2021

BB #76: The Holographic Theory

By Wyrd Smythe

I finished reading Three Roads to Quantum Gravity (2001), by Lee Smolin, a theoretical physicist whose general sensibility I’ve always appreciated. I don’t always agree with his ideas, but I like the thoughtful way he expresses them. Smolin brings some philosophical thinking to his physics.

While he added a lengthy Postscript to the 2017 edition, the book is outdated both by time and by Smolin. In 2006 he published The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next, which explored issues in the practice of theoretical physics. But in 2001 he still thought string theory was (at least part of) The Answer.

Almost none of which is the subject of this post.

15 Comments | tags: black hole, Lee Smolin, Loop Quantum Gravity, quantum gravity | posted in Books, Brain Bubble

September 3, 2021

Pancomputation III

By Wyrd Smythe

Oh, look! Dancing Pixies!

In the last two posts I’ve explored some ideas about what a computer is. More properly, what a computation is, since a computer is just something that does a computation. I’ve differentiated computation from calculation and, more importantly, evaluation. (This post assumes you’ve read Part I and Part II.)

I’ve also looked at pancomputationalism (the idea everything computes). The post hoc approach of mapping of random physical states to a computation seems especially empty. The idea of treating the physical dynamics of a system as a computation has more interesting and viable features.

That’s where I’ll pick things up.

4 Comments | tags: analog computer, computation, computationalism, digital computer | posted in Computers, Science

September 2, 2021

Pancomputation II

By Wyrd Smythe

Computer cluster?

Last time I began exploring what we mean by the terms “computer” or “computation.” Upon examination, these turn out to be not entirely obvious, so some resort to the edge cases: Computers are Turing Machines; or Everything is a computer.

Even then the situation remains stubbornly not obvious. Turing Machines are abstractions quite different from what we typically call computers. Saying everything computes creates such a broad umbrella that it renders the notion of computation nearly useless.

This series explores the territory between those edge cases.

7 Comments | tags: analog computer, computation, digital computer | posted in Computers, Science

September 1, 2021

Pancomputation I

By Wyrd Smythe

Two computers?

Earlier this year I wrote a trilogy of posts exploring digital dualism — the notion that a (conventional) computer has a physical layer that implements a causally distinct abstract layer. In writing those posts I found my definition of computation shifting slightly to embrace the notion of that dualism.

The phrase “a (conventional) computer” needs unpacking. What is a computer, and what makes one conventional? Computer science offers a mathematical view. Philosophy, as it often does, spirals in on the topic and offers a variety of pancomputation views.

In this series I’ll explore some of those views.

5 Comments | tags: analog computer, computation, digital computer | posted in Computers, Science