Sunday, April 9, 2017

An Introduction to the Anthropic Principle and Fine Tuning

Most of the readers of this blog have probably heard about the anthropic principle and the fine-tuning of the universe.  However, because future posts will discuss the ramifications and speculations about fine-tuning, I thought it would be prudent to give a brief overview of these topics. Although not identical, the anthropic principle and the fine-tuning are definitely related.

The anthropic principle takes different forms, but is basically the idea that the universe has the necessary conditions for the existence of any conscious being that is able to observe the universe.  These conditions could, in principle, be very narrow or very broad in their scope. Many of the observations about the anthropic nature of our universe were developed beginning in the 1960's and continue to this day. Perhaps the most definitive book on the subject was written in 1986 by John Barrow and Frank Tipler, The Anthropic Cosmological Principle. The authors actually develop four anthropic principles with the first one, the Weak Anthropic Principle, being the most well known and uncontroversial principle, "The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirements that the universe be old enough for it to have already done so"1

Although the parameters required for life to exist could, in theory, span a large or small range, it turns out that many of the parameters necessary for life to exist in our universe must fall within a very narrow region, or the universe would either not exist or not be able to support life. The fact that the conditions for life fall into such a narrow range, plus the many incredible mechanisms that give rise to the needed building blocks of life, constitute the fine-tuning of the universe.

I liken the finely-tuned universe to a panel that controls the parameters of the universe with about 100 knobs that can be set to certain values. If you turn any knob just a little to the right or to the left the result is either a universe that is inhospitable to life or no universe at all.

Saturday, March 25, 2017

The Second Law of Thermodynamics: An excerpt from the Dictionary of Christianity and Science

On April 25, 2017, Zondervan will publish the Dictionary of Christianity and Science. This is the definitive reference book discussing the intersection of Christian faith and contemporary science.  It has been a project that has taken over five years to complete. The four general editors, Paul Copan, Tremper Longman III, Christopher L. Reese, and myself have worked with over 100 outstanding contributors and our amazing editor, Madison Trammel, to bring this book to fruition.

There are a few features of this book that separate it from other such works. While most articles in the dictionary are unbiased, for topics that are controversial among Christians, the Dictionary presents various advocacy articles with opposing views. For instance, different views on evolution and the length of the days of creation are included. These articles represent the viewpoint of the author and are not completely unbiased. This multiple presentation model serves as a great resource for each reader to understand the complexities of the issue and come to his or her own conclusions.

Most of the articles in the Dictionary relate the particular subject to some aspect of Christian thought. For instance, articles on Special Relativity or Conservation of Energy have a concluding paragraph that mentions how some aspect of that subject relates to the character of God. This feature that explicitly discusses the intersection of science and faith distinguishes this reference book from others.

I have written 22 of the 450 or so articles. If you preorder the Dictionary you will get a number of bonus features including a presentation slide deck discussing String Theory which includes one of the articles I wrote on that subject. As an introduction to the Dictionary the rest of this post reproduces the entry I have written on the Second Law of Thermodynamics. This reprint is copyrighted by Zondervan and the four general editors and is used by permission. At the end of this article I briefly discuss the relationship of the second law of thermodynamics to biological evolution. I want to point out that I am not advocating for evolution but just stating facts regarding whether or not evolution violates the second law of thermodynamics.

Wednesday, March 15, 2017

A Universe From Nothing?

Could the universe spontaneously come into existence from nothing as the astrophysicist Lawrence Krauss has proposed in his 2012 book, A Universe From Nothing: Why there is something rather than nothing? And what is this "nothing" that Lawrence Krauss has proposed? Is it actually no thing? Does Krauss's proposal eliminate the theists' claim that the Big Bang beginning of the universe requires a transcendent cause that is not bound by space and time? The publication of this book generated a significant dialogue that dealt with these questions. Although initial publication of the book was five years ago I still consistently get asked questions about its content and the scientific validity of its proposals. I think it is important and valuable to address these issues from both a scientific and Christian perspective.

Saturday, March 4, 2017

Looking for God in Nature


One of the biggest misconceptions in the discussion about science and faith has to do with our ability to explain natural phenomena and what those explanations imply about God's actions in the universe. This is a misconception that is explicitly held by many who don't believe in God and implicitly held by many who do believe in God. The result of believing this idea is a complete misunderstanding of God and biblical teaching, and leads to false conclusions about God's involvement in the natural world. The misconception is the idea that if science has developed a naturalistic explanation for some phenomena then that removes God's involvement from the process. A closely related corollary to this misconception is the idea that if there is a phenomena that we can't explain, then God must be the explanation. This latter corollary is called the "god of the gaps". We invoke God as an explanation for things we don't understand.  Both of these ideas, a god of the gaps argument or the idea that a scientific explanation removes God, are false, unbiblical, poorly reasoned, and lead to incorrect conclusions.

Saturday, February 25, 2017

A Small Big Universe

The universe is unfathomably large. Our galaxy, the Milky Way, is made of around 200,000,000,000 stars and there are about 200,000,000,000 galaxies in the visible universe. The Milky Way galaxy is about 100,000 light years across, which is  9.5 × 1017 km (6 × 1017 miles). (A light year is the distance light travels in a year which is 9,500,000,000,000 km or 6,000,000,000,000 miles.) We can see galaxies that are so far away it has taken about 13 billion years for their light to reach us.  Since the universe is expanding, those galaxies have continued to recede away from us during the time it took their light to reach us. So the present size of the known universe is approximately 93,000,000,000 light years across in all directions. That is, the universe we can see is now a sphere about 9 × 1023 km (6 × 1023 miles) in diameter. We talk about the "visible" or "known" universe because that is all of the universe we can see. We have no idea how large the universe is beyond that.

It is impossible to understand how big this is. Consider something much smaller, the distance to the nearest star which is about 4.3 light years away. If we could travel to that star at about the same speed as the Apollo astronauts traveled to the moon, it would take almost 1 million years to get there. That is just to the closest star in our galaxy! Even if we could travel at the fastest speed of any object ever created by humans it would take about 30,000 years to reach the nearest star.  You can do the math, but even at that extreme speed it would take 700,000,000 years to cross our galaxy.

Friday, February 17, 2017

The World at CERN



And now for something completely different...  The main focus of this blog is to discuss issues relating science and reason to Christianity and God.  However, I have spent the last week at CERN attending meetings, talking with people, trying to develop computer code to analyze data, and other such activities.  So I'm going to take this opportunity to talk about how experimental particle physics research is done within large collaborations like those at CERN.

I am a member of the ATLAS collaboration.  ATLAS is the name given to both the detector that we use to analyze data from proton-proton collisions at the Large Hadron Collider and the group of scientists who use the data from that detector to try to understand the fundamental particles and forces in the universe.  There are currently about 5000 scientists from about 180 institutions in 38 countries who are members of the ATLAS collaboration, with 1200 of those scientists being students working toward their Ph.D.  It takes that many people to operate the ATLAS detector and to analyze all of the data that we take with the detector.