Tag Archives: Physics

A Guide to Reality, Part 2

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A couple days ago, I stated my intention (you might even say I promised) to work through Alex Rosenberg’s The Atheist’s Guide to Reality: Enjoying Life Without IIlusions right here at WOCS. That was in part 1. Believe it or not, this is part 2.

In his preface, Professor Rosenberg explains that he wrote the book for people who are ready to face reality. By that he means people who believe there is no God (atheists) or have serious doubts (agnostics) and who want to know what science has to say about a few perennial questions that keep some of us awake at night. He thinks the scientific view of reality has certain consequences:

The book is about those consequences. It provides an uncompromising, hard-boiled, no-nonsense, unsentimental view of the nature of reality, the purpose of things, the meaning of life, the trajectory of human history, morality and mortality, the will, the mind and the self (ix).

Rosenberg scoffs at attempts to reconcile science and religion. He holds that “an unblinking scientific worldview requires atheism” (viii), which explains why most of America’s leading scientists are atheists and those who aren’t atheists are mostly agnostics.

I don’t think it makes any difference to Rosenberg whether science leads us to atheism or atheism leads us to science. He started out in physics, ended up in philosophy, branched out to biology and economics, and somewhere along the way became an atheist. But someone might proceed in the other direction: doubting God’s existence and then looking to science to explain why the world is the way it is. His contention is that science and atheism are compatible, while science and religion (or theism) aren’t.

In my opinion, however, he exaggerates the conflict. You don’t have to deny God’s existence in order to be an excellent scientist. Instead, what you need to do is put thoughts of God aside when you’re doing science. Science is the search for natural explanations, not supernatural ones. Invoking God as the explanation for the existence of the human eye, for example, amounts to throwing up your hands and choosing a different subject. If you want to speculate about some god or other creating the universe and initializing the fundamental constants (like the mass of an electron) to values supportive of life, you’re not doing science. In this methodological sense, a scientist has to be an atheist.

But despite what Rosenberg says, nobody knows why or how the universe came into existence; or if it’s always existed in some form or other; or whether our universe is one of many. Even if scientists eventually figure out the answers to those questions, we’ll never be able to rule out the possibility that some creator or creative force beyond our universe got the cosmic ball rolling. Nor will we ever be able to prove that God, Zeus or Santa Claus isn’t watching right now to see if we’ve been naughty or nice. What evidence could there be to prove that kind of negative?

What we can say is that, historically speaking, science has shown a vast number of previously mysterious phenomena to be natural processes. There is no reason to think we need an entity outside space and time to explain why there are stars and galaxies, or why there are birds and bees, or why the Red Sox sold Babe Ruth. As fewer phenomena have seemed to require a supernatural explanation, it has seemed less and less likely that there is Anyone Up There. As we’ve learned more about our world, ancient stories have become much less plausible. So far as science is concerned, God is a dead letter.

But that doesn’t necessarily mean God is dead, however implausible that he, she, it or they either are or ever were “alive”.

Next time: stories and scientism.

A Guide to Reality, Part 1

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Alex Rosenberg is the R. Taylor Cole Professor of Philosophy and chairman of the philosophy department at Duke University. He’s published more than 100 articles and reviews. Among his books are Microeconomic Laws: A Philosophical Analysis, Hume and the Problem of Causation, The Structure of Biological Science and Darwinian Reductionism. Like most philosophers these days, he writes for an academic audience. In 2011, however, he published a book for a general audience: The Atheist’s Guide to Reality: Enjoying Life Without Illusions.

The title is a little misleading, since Rosenberg derives his atheism from a more fundamental belief called “scientism”. That’s the view according to which, in Rosenberg’s words, “the methods of science are the only reliable ways to secure knowledge of anything”. Unfortunately, there is no word for a person who accepts scientism other than “scientist” and you can be a scientist without believing in scientism. For that matter, you can be an atheist without believing in scientism. 

On the other hand, if you’re sure of God’s existence, The Atheist’s Guide to Reality probably won’t change your mind. It’s a book for people who are willing to take science extremely seriously, even to the point of concluding that many of humanity’s most common beliefs are wrong. Since I’m one of those people, I enjoyed the book, even while disagreeing with some of Rosenberg’s conclusions.

Because The Atheist’s Guide is well-written and covers so much ground (for example, physics, evolution, perception, consciousness, free will, history and morality), I thought it would be an interesting exercise to work through it, explaining and responding to Professor Rosenberg’s views right here on this blog (while continuing to write about other things, like class warfare and mowing the lawn). 

If you want to consider the professor’s views first-hand and be able to correct my account of what he has to say (assuming you want to participate), the paperback and electronic versions are going for less than $15 online.

9780393344110_p0_v1_s260x420

Next time:  the relationship between science and atheism.

The Atheist’s Guide to Reality: Enjoying Life Without Illusions by Alex Rosenberg

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The author is a professor of philosophy at Duke University who usually writes books for other philosophers and people who aspire to be philosophers. This one was written for a general audience. Maybe that’s why the book comes on so strong. Borrowing Nietzsche’s phrase, it’s philosophy with a hammer.

I assume Professor Rosenberg chose the title, but it’s a little misleading. Rosenberg derives his atheism from a more fundamental view called “scientism”. He defines that as the worldview according to which “the methods of science are the only reliable ways to secure knowledge of anything”. Unfortunately, there is no word that refers to someone who accepts scientism except “scientist” and you can definitely be a scientist without believing in scientism. Plus, a title like The Guide to Reality for People Who Accept Scientism isn’t exactly catchy. So “The Atheist’s Guide to Reality” it is.

One way Rosenberg explains scientism is to say that physics fixes all the facts (except, presumably, for the facts of logic or mathematics). Physics says that all events in the history of the universe, except some at the quantum level, are determined by previous events and the laws of nature. Furthermore, the Second Law of Thermodynamics (entropy ultimately increases in an isolated system) is the “driving force” behind evolution, which is the result of haphazard genetic mutation. Evolution gave us minds, but our minds are nothing more than the activity of our brains.

Rosenberg concludes that we don’t have free will, introspection is generally misleading and thoughts (whether conscious or unconscious) aren’t “about” anything (since what happens in a neuron can’t be “about” anything — it’s just a tiny input/output device). Furthermore, there are no purposes in nature, even in our minds, and there are no ethical facts. Morality is just another evolutionary adaptation. In addition, we can learn nothing from history or economics, since human culture is constantly evolving.

Rosenberg expresses his conclusions with an air of almost absolute certainty, which is odd for someone who believes in science (maybe it’s not so odd for someone who believes in scientism). For example, he says that “what we know about physical and biological science makes the existence of God less probable than the existence of Santa Claus”. Perhaps he’s being facetious in that passage, but many atheist or agnostic philosophers would agree that God’s existence is a metaphysical question beyond the reach of science. Natural processes don’t count for or against the supernatural. Besides which, there is no evidence at all for the existence of Santa Claus.

Getting to the Bottom of Things Physics-Wise

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One of the things that made physicist Richard Feynman famous was his invention of the Feynman diagram. Feynman diagrams provide a method for understanding the interactions between sub-atomic particles. Here, for example, is a diagram that represents the collision of an electron and a positron, resulting in the creation of two photons:

640px-Feynman_EP_Annihilation.svg

Using Feynman diagrams to describe certain interactions turns out to be extremely challenging, however. The collision of two gluons, resulting in the creation of four less energetic gluons, requires 220 diagrams. Some calculations based on this methodology cannot be done without the aid of a powerful computer, since they require thousands, millions and even billions of mathematical terms.

Over the years, various physicists and mathematicians have found ways to simplify these calculations. Recently, in fact, physicists have discovered a new geometrical object, the use of which simplifies the calculations to an amazing degree. They call the new structure an “amplituhedron”:

Interactions that were previously calculated with mathematical formulas thousands of terms long can now be described by computing the volume of the corresponding jewel-like “amplituhedron,” which yields an equivalent one-term expression.

“The degree of efficiency is mind-boggling,” said Jacob Bourjaily, … one of the researchers who developed the new idea. “You can easily do, on paper, computations that weren’t feasible even with a computer before.”

For example, calculating the volume of the amplituhedron in this diagram, which represents the interaction of 8 gluons, provides the same result as 500 pages of algebra based on Feynman diagrams:

amplituhedron-drawing_web

I learned about this latest development in an article called “A Jewel at the Heart of Physics”, which can be found here:

https://www.simonsfoundation.org/quanta/20130917-a-jewel-at-the-heart-of-quantum-physics/

The article suggests that the discovery of the amplituhedron might one day lead to major consequences for our understanding of the universe: “a theory of quantum gravity that would seamlessly connect the large- and small-scale pictures of the universe”:

Attempts thus far to incorporate gravity into the laws of physics at the quantum scale have run up against nonsensical infinities and deep paradoxes. …The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry. The usual picture of space and time, and particles moving around in them, is a construct.

If two methods give the same results, the simpler method is clearly preferable from a pragmatic point of view. In fact, it’s likely in such a case that the simpler method better reflects the way the universe works. Perhaps the simplicity of this new method indicates that fundamental reality is simpler than previously believed:

Beyond making calculations easier or possibly leading the way to quantum gravity, the discovery of the amplituhedron could cause an even more profound shift, [physicist Nima] Arkani-Hamed said. That is, giving up space and time as fundamental constituents of nature and figuring out how the Big Bang and cosmological evolution of the universe arose out of pure geometry.

“In a sense, we would see that change arises from the structure of the object,” he said. “But it’s not from the object changing. The object is basically timeless.”

None of this means that there are tiny amplituhedrons underlying the universe, floating around outside space and time (whatever that would mean). It’s not even clear (to me anyway) what “pure geometry” is, since the geometry of an object, whether real or imagined, usually refers to its spatial characteristics.

Nevertheless, this latest labor-saving device may help physicists get closer to the bottom of things, assuming there is a bottom to get to.

Getting Down to the Truly Nitty Gritty

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I live near one of the research centers that used to be known as Bell Labs, the place where scientists found evidence of the Big Bang; invented the transistor and the laser; and developed the UNIX operating system and C programming language. A friend once suggested that I try to get a job there, since they would always need janitors.

Nevertheless, even with my weak qualifications, I enjoy reading about theoretical physics. I didn’t understand much of the article below, but it’s good to know that physicists are trying to understand where space and time come from. You might think space and time are fundamental, but there appears to be more to the story.

If you follow the link to the article, you can click on this diagram and make it bigger (spatially, not temporally).

quantum-gravity-nature-online

http://www.nature.com/news/theoretical-physics-the-origins-of-space-and-time-1.13613