Sunday, May 21, 2017

Extraordinary Claims and Extraordinary Evidence

"Extraordinary claims require extraordinary evidence" is a phrase that was popularized by Carl Sagan but has its roots from at least the 18th century Enlightenment when the miracles of Christianity were being questioned by certain intellectual thinkers of the day. The most famous Enlightenment critic of Christianity was probably David Hume who wrote an essay called Of Miracles in 1748 where he states, "Suppose, for instance, that the fact, which the testimony endeavours to establish, partakes of the extraordinary and the marvellous; in that case, the evidence, resulting from the testimony, admits of a diminution, greater or less, in proportion as the fact is more or less unusual."

At first this statement may sound reasonable. For instance, I am more likely to believe you if you tell me you had breakfast this morning than I would believe you if you told me that you levitated off the ground this morning without anything holding you up. But does the fact that I believe you if you say you did something ordinary and I don't believe you if you say you did something extraordinary support the statement that "Extraordinary claims require extraordinary evidence?" Actually, it doesn't. Although I may believe that you ate breakfast this morning, I must obtain supporting evidence if I want to actually determine whether or not that fact is true. If you have cleaned up your kitchen, such evidence may be hard to find. I might have to pump out the contents of your stomach, for instance to see what you ate and when you ate it. It is one thing to say that I believe you ate breakfast because it is an "ordinary" event, but it is quite another to actually find enough evidence to validate your claim. My point is that actual validation of any event requires sufficient evidence.

Sunday, April 30, 2017

Some Thoughts on a Multiverse

It may sound more like science fiction than serious science, but many scientists have recently embraced the idea that there may be many more universes than just our own.  Such an idea can produce a great science fiction story, such as that in the original Star Trek episode "Mirror Mirror" where a transporter accident causes Captain Kirk to move to an alternative universe that is more brutal and savage aboard its version of the Starship Enterprise.

There are a few different scenarios for producing many universes (or a "multiverse") within proposed scientific theories.  One mechanism is the probabilistic nature of quantum mechanics. The "many worlds" interpretation of quantum mechanics proposes that every time a quantum event occurs that has multiple possible outcomes, all outcomes are produced in some universe. This is similar to saying something like every time I flip a coin, if a "heads" shows up, then an additional universe branches off from ours in which everything is the same except the coin shows "tails." Not many scientists actually believe that quantum mechanics produces these universes, but some do.

A different scenario that produces many universes is called "eternal inflation" in which our universe is somewhat like one bubble in a boiling pot of water, but there are many other bubble universes that are also produced. This theory of eternal inflation1 is an extension of the inflationary big bang model in which our universe had a period of rapid expansion in the first 10-35 seconds. In the eternal inflation model, the rapid expansion may have stopped in our universe but continued in others producing many other universes.
Perhaps the most popular theory that includes a multiverse is string theory, that postulates the fundamental particles we know of, like quarks and leptons, are composed of "vibrating strings of energy."  String theory requires that the universe is actually composed of 10 dimensions, rather than just the three dimensions of space and one dimension of time that we are familiar with.  Different string theories can be derived from an even more exotic theory, called "M-theory" which requires an 11 dimensional universe.  I'm not an expert on string theory so I don't understand all of the calculations that produce the string theory landscape, but my understanding is that there are many different minimum energy states (vacua) within string theory and any universe could occupy one of those states.  Depending on certain assumptions the number of possible vacua is often estimated at something like 10500. This means that there are 10500 different kinds of possible universes, but since every one of these universes could be duplicated many times within string theory, there could even be many more universes than that unimaginably large number.

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.

Saturday, February 4, 2017

A Changing Arrow of Time?

This is one post I am not looking forward to writing.  Some of my readers have asked me to comment about alternative theories to the Big Bang which remove the necessity of our universe having a beginning.  I have been thinking for some time about how to write on this subject in a non-technical manner, which is the tone I strive for on this blog.  Because most of these ideas are quite theoretical, requiring complex mathematics and intricate nuances, it is quite a challenge for me to give an accurate and adequate description of most of these proposals, yet still be comprehensible.   Nevertheless, in this post I want to try to discuss the paper by Anthony Aguirre and Steven Gratton (AG) that describes a scenario which they claim requires no beginning.1   I also want to give some thoughts on how their idea fits into the whole discussion of evidence for or against a deity, particularly the Christian God.  My attempt may be an epic fail.

In the model proposed by Aguirre and Gratton, they claim to avoid a beginning by proposing a thermodynamic arrow of time that points in different directions depending on whether the universe is expanding or collapsing.  To understand what this means I need to first take a diversion to discuss what the thermodynamic arrow of time means.  Actually, no one really knows for sure why we experience time moving forward but we do know that a quantity called entropy must increase in any non-reversible process.  Entropy strictly has to do with the number of microstates available to a system. The concept of a microstate can be illustrated by considering two six-sided dice. There is only one microstate available for the dice to roll 2: both must show a one. However, there are six possible microstates available for the dice to roll a 7. The combinations are 1 and 6, 2 and 5, 3 and 4, 4 and 3, 5 and 2, or 6 and 1. Because there are more available microstates, the dice will more often roll a 7. A macroscopic system with more available microstates has a greater entropy than one with fewer microstates. The second law of thermodynamics states that an isolated system will evolve spontaneously to the state with maximum entropy.   This is a statistical idea.  In general, all processes move toward those that are more statistically probable.  That gives us the arrow of time.   Time moves in the direction where entropy increases.

Saturday, January 28, 2017

The Significance of the BGV Theorem

Let's continue to explore the question of whether or not our universe had an actual beginning.  In two previous posts I have said that (1) if our universe had a beginning, then the cause of the universe must be transcendent, a characteristic of the Christian God, and (2) we may never have any observational or theoretical evidence about what happened in the first 10-35 seconds of the universe.

However, there have still been a lot of ideas from theoretical physicists about what may have happened to bring the universe into being and what we can surmise from the equations and laws that we know describe our universe.  One of the most often discussed papers dealing with our past was published by Arvind Borde, Alan H. Guth, and Alexander Vilenkin in 20031 and called the BGV theorem after the three authors.  In this paper, the authors show that any universe which is on average expanding has a timeline that cannot be infinite into the past, it must have had a beginning when it started to expand.  Since our universe is known to be expanding this theorem seems to require that it had a beginning.  (There are some technicalities to this conclusion like, for instance, the difference between "expanding" and "on average expanding" but, in general, what is known about our universe corresponds with the requirements of the BGV theorem.)

Saturday, January 21, 2017

A Singularity at the Beginning?

A previous post about the Big Bang elicited a few comments and questions about alternative scenarios for the origin of our universe that would not require an actual beginning.  I'd like to respond to those questions, but I think it would be beneficial to first discuss some of the scientific challenges that are faced when we try to understand what happened in the first 10-35 seconds of the universe.

One major challenge is to try to determine what laws of physics are applicable during that time.   This is a problem that you may have already heard about for it has to do with the incompatibility between Quantum Mechanics and General Relativity.  If you do a web search about this subject, you will find multitudes of articles written, from those that are quite basic to those that are quite technical.  The purpose of my blog is to describe things accurately, but simply, so my discussion will necessarily be basic.

Monday, January 16, 2017

Proof, Evidence, Science, and Christianity

In my previous post I said that the Big Bang was evidence for the existence of God, though not proof.  This raises the question of whether or not there is proof for God, or for that matter, whether or not there is proof for anything, even within the scientific realm.   

If by proof, we mean absolute certainty of truth without any doubt or possibility of exception, then proof is not possible within a scientific framework.  Proofs are only possible in logic and in mathematics where there are well defined rules within the discipline.  In those two fields, once a proposition has been proven, that proof is complete and will remain valid.  In contrast, scientific knowledge is the best explanation for the results of current experimental observations among all the available options.  As additional evidence and observations are made, the facts may require modifications and adjustments to the theory.  If an experiment is done that contradicts the current scientific paradigm, then that theory is not wholly true and must be refined or discarded.  Therefore, scientific ideas can be disproved, but never absolutely proven.  

Tuesday, January 10, 2017

Should the Big Bang be Disdained?

When my children were young, I would often drive to the home of the person babysitting my kids, usually a young teenage girl, pick her up, then drive her back to my house.  In the car I would ask questions about her interests or her school.  In addition, I would sometimes ask a question that intrigued me since I am a scientist and a Christian, "Do you think the Big Bang is a theistic theory or an atheistic theory?"  Now that question is not on most people’s list of babysitter interview questions, but I was interested to know their answer even though it would not affect their monetary tip.  Every time I asked this question I always got the same answer, that the Big Bang is an atheistic theory.  This is just one example of the fact that many kids growing up in an evangelical church environment have the perception that the Big Bang is an idea which removes God as the creator.  It seems that many Christians may disdain the Big Bang.

Subsequent conversations with people of all ages have shown me that many individuals (1) don't really understand what the Big Bang is, (2) don't know the scientific evidence for the Big Bang, and (3) don't comprehend the theistic significance of the Big Bang.   So let's explore these ideas a little bit.  The ultimate conclusion for me is that the Big Bang is among the very best objective evidence available for the existence of God, and is consistent with the biblical record.  Many of you readers probably already know much of what follows, but maybe you will find something of interest anyway.

Thursday, January 5, 2017

The God Particle...and God

On July 4, 2012 two collaborations of over 3000 physicist each independently announced the discovery of a particle colloquially known as "The God Particle."  Where did this elusive particle get its name?  Why did its discovery make international news?  And does it have anything to do with God?

Every scientist I know dislikes the moniker "The God Particle."  Physicists, instead, have named the particle after one of the six people who predicted its existence in 1964, the British theoretical physicist Peter Higgs.  Thus, it is the "Higgs particle" or "Higgs boson."  (For those of you who don't know but care about such things, a boson is a subatomic particle with an intrinsic quantum mechanical property of spin equal to an integer value times the Planck constant, named after Indian physicist Satyendra Nath Bose.)

In 1993, Leon Lederman, a Nobel Prize winning physicist, wrote a book about the search for the Higgs boson and named the book The God Particle at the urging of his publisher in order to maximize sales.  So the nickname "The God Particle" is mostly a marketing gimmick to sell books.  The name doesn't give any insight into the particle's properties or its place in the ensemble of fundamental particles.

Sunday, January 1, 2017

The Soul of the Artist

I have a friend who is quite an accomplished artist.  In fact, one of his paintings (shown above) hangs in the main gallery of the Oklahoma Capitol Building.  He has told me that when you look at a piece of art, you see the soul of the artist.  When I look at a piece of art I often just see the superficial subject and colors.  But an art aficionado would truly see the soul of the artist in things like the intricate technique used to paint the picture, or the subtle use of light and shadow, or the way the artist has created a scene that draws your eyes from one place to another.

As a scientist, I have the privilege of looking at God's work of art, his creative work called the universe, and seeing his soul.  Like the art expert, I may be able to see things in the creation that give me insight into the Artist's soul in a way that the casual observer might not notice.