Tag Archives: Astrophysics

Events

Upcoming Greer-Heard forum on cosmology, featuring Sean Carroll and William Lane Craig

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(Video: William Lane Craig debates the fine-tuning argument with Duke University philosopher Alex Rosenberg)

Christian Post reports on what promises to be one of the best debates in William Lane Craig’s career.

Excerpt:

The debate over God’s existence heats up next week as leading physicist and atheist Sean Carroll is pitted against William Lane Craig, a top theologian and philosopher, to discuss their views about philosophy, cosmology, and the role of God and the cosmos.

The two experts will debate on Feb. 21 under the theme “God and Cosmology: The Existence of God in Light of Modern Cosmology.” Organizers announced Wednesday that the event will be held at New Orleans Baptist Theological Seminary as part of a Greer-Heard Point-Counterpoint Forum in Faith and Culture Weekend Conference. Modern cosmology is dominated by the Big Bang theory, which attempts to bring together observational astronomy and particle physics.

“Though Carroll is as fiercely anti-theistic as other cosmologists I have debated, he differs in being philosophically informed and civil in demeanor,” Craig wrote in a statement about the event.

Craig is a philosopher, professor, author and founder of ReasonableFaith.org, a web-based ministry “whose purpose is to provide, in the public arena, an intelligent and articulate perspective about the existence of God.” He has debated some of the most notable atheists, including the late Christopher Hitchens, Richard Dawkins, and, most recently, Lawrence Krauss. Some 250,000 people have watched the Craig-Krauss dialogues since they took place last August in Australia.

Over the years, Craig has developed “Eight Reasons for God.” These form his case for theism, showing that God is the best explanation for why anything exists at all; the origin of the universe; the application of mathematics to the physical world; the fine-tuning of the universe for intelligent life; intentional states of consciousness in the world; objective moral values and duties in the world; the historical facts concerning Jesus’ resurrection; and personal experience of God.

Sean Carroll is a physicist at the California Institute of Technology. His research focuses on theoretical physics and cosmology, especially the origin and constituents of the universe. He has contributed to models of interaction between dark matter, dark energy, and ordinary matter; alternative theories of gravity; and violations of fundamental symmetries. He has appeared on TV shows including “The Colbert Report” and Through the Wormhole with Morgan Freeman, and frequently serves as a science consultant for film and television. He is the author of several books including the upcoming The Particle at the End of the Universe.

Each has selected two commentators to round out the discussion, philosophers Tim Maudlin and Alex Rosenberg on Carroll’s tag team and philosopher Robin Collins and physicist James Sinclair on Craig’s. A follow-up discussion is planned for that Saturday.

“I selected the physicist James Sinclair, with whom I co-authored the article on the kalam cosmological argument in the Blackwell Companion to Natural Theology, and Robin Collins, who is writing what will be the definitive book on the fine-tuning of the universe,” said Craig. “Carroll and I will be afforded the opportunity to give brief responses to each of their papers.

“There will also be opportunity for audience interaction with all the participants. Not only will the entire proceedings be video-recorded, but the transcript of the debate, papers, and responses will be published by Fortress Press. So this promises to be a very substantive and important engagement. It will also be live-streamed on the Internet, so you can join in if you’d like.”

The post includes a link to the live stream, which is provided by Tactical Faith.

Dr. Carroll’s blog post about the debate

Dr. Carroll posted about this upcoming debate on his blog, and it seems like he is is going to be a fine opponent for Dr. Craig.

Excerpt: (links removed)

Next month I’ll be doing something related, although under quite different circumstances. On February 21 I’ll be debating William Lane Craig at the Greer-Heard Forum, an event sponsored by the New Orleans Baptist Theological Seminary. It will actually be a two-day event; a debate between Craig and me on Friday night, and follow-ups on Saturday from other speakers — Tim Maudlin and Alex Rosenberg for Team Naturalism, Robin Collins and James Sinclair for Team Theism.

[…]William Lane Craig (or WLC as we call him in the business) is of course a very well-known figure, largely for his many public debates, on theism/atheism as well as on various other specific theological issues. As far as debating goes: he’s very good at it! If his debates were being judged by a panel of experts as in an intercollegiate debate tournament, he would have a very good record indeed. This has led many people to conclude that atheists just shouldn’t debate him at all, or at least not until they have devoted 10,000 hours to learning how to be a good debater.

Daniel Dennett warned me that, as soon as word got out that I would be debating WLC, I would be deluged with opinions and unsolicited advice. Which is great! Always happy to hear other perspectives, although I don’t promise to actually follow any of the advice. I won’t reproduce the various emails I’ve received, but here are a few very different perspectives online: Jerry Coyne, Luke Barnes (and another), and Wintery Knight. (WK is relatively restrained, but others predict “pummelings,” presumably for me.)

Dr. Carroll explained his goals for the event:

Just so we’re clear: my goal here is not to win the debate. It is to say things that are true and understandable, and establish a reasonable case for naturalism, especially focusing on issues related to cosmology. I will prepare, of course, but I’m not going to watch hours of previous debates, nor buy a small library of books so that I may anticipate all of WLC’s possible responses to my arguments. I have a day job, and frankly I’d rather spend my time thinking about quantum cosmology than about the cosmological argument for God’s existence. If this event were the Final Contest to Establish the One True Worldview, I might drop everything to focus on it. But it’s not; it’s an opportunity to make my point of view a little clearer to a group of people who don’t already agree with me.

Recently, Dr. Carroll debated Christian philosopher Hans Halvorson, who is a professor at Princeton University, and Hugh Ross was in attendance. In a podcast, Dr. Ross said that Carroll was a gentleman, and it was a good debate, although he wanted Halvorson to disagree with Carroll more. (You can watch the “debate” here, although it really wasn’t a debate because Halvorson didn’t engage Carroll for the most part). Reasons to Believe has since pulled the podcast. However, I was able to find it, (I am a software engineer!), and I’ve posted it here. I have no idea why they pulled it, because it was a good review. If you want a good introduction to the issues they’ll be debating from a particle physicist, check out this recent lecture by Dr. Michael Strauss.

The two duelists choose their seconds

My understanding is that Dr. Carroll has already made one mistake. He selected Alex Rosenberg (see video above) as a respondent. Dr. Rosenberg is not a good spokesman for naturalism, and in his debate with Dr. Craig, he did very poorly. A better wingman would have been someone like Graham Oppy or Quentin Smith. Dr. Carroll’s other choice (Tim Maudlin) looks solid, though.

On Dr. Craig’s side, he’s chosen Robin Collins and James Sinclair. Collins recently had a chapter in “Debating Christian Theism” (Oxford University Press, 2013) and Collins and Sinclair both had chapters in “The Blackwell Companion to Natural Theology” (Wiley-Blackwell, 2009). Collins is an engaging public speaker, and I featured a lecture by him on the fine-tuning argument in this post.

Please pray that God would reach out to Dr. Carroll and for other non-theists listening to the debate so they can see that there are good reasons for them to rethink their views about God.

Dr. Luke Barnes previews the debate

If you would like to read some comments from an accomplished cosmologist, check out these posts (post one, post two, post three, post four) on Dr. Luke Barnes’ Letters to Nature blog. You might remember him because I wrote about his paper critical of atheist physicist Victor Stenger in this blog post. Note that Barnes’ paper has now been published in a peer-reviewed journal. The journal is published by Cambridge University.

Podcasts

Lawrence Krauss debates “A Universe From Nothing” with an astrophysicist

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Dina sent me news of Saturday’s episode of Unbelievable, which features Lawrence Krauss, who debated William Lane Craig. Krauss’ book was also reviewed in the New York Times.

The MP3 file is here.

Details:

Lawrence Krauss is a Cosmologist at Arizona State University who describes himself as an “anti-theist”. His latest book “A Universe From Nothing” has received both acclaim and criticism for its attempt to answer the question “Why is there something rather than nothing?” Debating the issue with Krauss is Rodney Holder, Course director at the Faraday Institute, Cambridge. An astrophysicist and priest by background. In a lively exchange they debate whether Krauss’ “nothing” is “nothing”, fine tuning and multiverses, scientific knowledge, miracles and the usefulness of theology and philosophy.

This debate is quite entertaining, and do not be intimidated if your don’t understand science. You can understand pretty easily who is arguing based on facts and who is speculating about unobservable, untestable entities. At one point, Krauss actually denies that there is any fine-tuning in the universe, so please see this link to refute that claim as well as this podcast which explains some examples of fine-tuning. Krauss gets a bit angry at the beginning, but calms down.

Quotation marks are for direct quotes, italics is for made-up snark. See below the summary for more posts that are related to this one.

Summary of the discussion: (picked up at 9:30 when they start talking about the book)

Brierley:

  • explain your theory of how the universe can come into being from nothing

Krauss:

  • the nothing that preceded the universe is “no space, no time, no universe”
  • theists say that God is responsible for creating the universe out of this nothing
  • but the laws of nature can create the universe uncaused out of nothing

Holder:

  • Krauss sometimes writes that the nothing is really a quantum vacuum, but that is not nothing
  • He even acknowledges in his book that a quantum vacuum is not nothing
  • He thinks that the nothing has properties, even though it has no being
  • It has the property of being unstable
  • It has the property of being acted on by quantum fields
  • It has the property of being acted on by gravity

Krauss:

  • But nothing can have the potential to do things inside it
  • For example suppose you have an electron, which is not nothing
  • If it jumps from one level to another, it emits light
  • There was no potential for the light in the electron, but it was there as part of atomic structure

Holder:

  • But in cases like that, there is something physical that has the potential
Krauss:
  • Well, how did God makes the universe then if it had no potential?

Holder:

  • God existed, and the potential for creating the universe in himself

Brierley:

Krauss:
  • It was written by a philosopher, so I dismissed it

Brierley:

Krauss:
  • These book reviewers have not even read my book!

Krauss:

  • Science will be able to figure out how to make something from nothing in the future
  • We are even now speculating about interesting questions, like is there a multiverse?

Brierley:

  • Consider the critical review of your book in the New York Times
  • The author of the review claims that you equivocate on the term “nothing”
  • In order to get things to pop into being, you have to make “nothing” mean “something”
  • Reviewer: none of Krauss’ theories explain how something can come from actual nothingness

Krauss:

  • In physics, something and nothing are not that different
  • The reviewer doesn’t understand the physics
  • He doesn’t understand quantum field theory
  • You could call a quantum vacuum “nothing”, (this is the vacuum fluctuation model, refuted by William Lane Craig in a peer-reviewed publication in an astrophysics journal – get the full text of the article here)
  • Maybe there is an eternally existing multiverse that we can’t observe or test scientifically
  • Maybe it has laws that we don’t know about which allow our universe to pop into being
  • Maybe this popping into being is uncaused
  • (alarmed) Who made God? Who made God?

Holder:

  • God is eternal and necessary

Krauss:

  • (interrupting, angry) What does it mean for something to be necessary?

Holder:

  • Basically, you have to decide whether there is more evidence that the necessary being God or a multiverse

Brierley:

  • So Dr. Krauss are you willing to say that the universe is a brute fact, in some sense, and requires no explanation

Krauss:

  • (angry) Religious people are stupid because they just assume brute facts, not like me and my unobservable, untestable multiverse
  • (angry) Religious people are against the progress of science, they don’t want to figure out how things work

Brierley:

  • But isn’t it possible that naturalists can be opposed to the progress of science?
  • What about the way the Fred Hoyle opposed the Big Bang because he wanted an eternal universe

Krauss:

  • (angry) But naturalists like me let the facts determine our beliefs, like the facts about the eternal unobservable, untestable multiverse
  • (angry, shouting) Philosophers are stupid, they know nothing!

=== Break ===

Brierley:

  • Do you see any evidence of purpose in the universe?

Krauss:

  • Well maybe I would believe if the stars lined up to spell out a message from God

Brierley:

  • Actually no, that wouldn’t be evidence for God on your multiverse view
  • if there an infinite number of universes existing for an infinite amount of time, then anything can happen no matter how unlikely it is
  • therefore, no evidence could convince you that God exists, since the unobservable, untestable, eternal multiverse can make anything it wants

Krauss:

  • That’s a true statement, and very convenient for atheists who don’t want to be accountable to God, don’t you think?
Brierley:
  • Back to the multiverse, how does it solve the fine-tuning?

Krauss:

  • “We have no idea if the universe is fine-tuned for life”, even though the atheist Martin Rees who endorsed Krauss’ book wrote his own book about the fine-tuning of the universe called “Just Six Numbers”
  • Inflationary theory does suggest a way to create multiple universes, (this is the chaotic inflationary model, refuted by William Lane Craig in a peer-reviewed publication in an astrophysics journal – get the full text of the article here)

Brierley:

  • But this theory is still very much a hypothesis, isn’t it? We can’t observe or test this hypothesis can we?

Krauss:

  • “No, and that is really important to state”
  • “I’m an empiricist, so if you can’t falsify it and if you can’t test it then it’s not science”
  • In my book, I speculate about a way that we could test the multiverse theory

Holder:

  • Yes, in principle, the multiverse would be scientific if you could test it through other theories like inflationary theory
  • There are a lot of speculations about multiverse theory, but no evidence from predictions that were validated in the lab

Krauss:

  • “I agree completely with everything you just said”

Brierley:

  • Roger Penrose agrees with Holder that the multiverse theory is too speculative
  • (To Holder) Isn’t the multiverse theory better than positing a completely different kind of being, which is God?

Holder:

  • The multiverse theory is extremely speculative
  • Even if the multiverse were true, you would still need to explain the multiverse

Krauss:

  • People don’t oppose my book because it’s full of self-contradictory speculations
  • People oppose my book because they are stupid and ignorant

Holder:

  • There are things that exist that science cannot measure, like objective morality
  • It’s possible to give explanations for moral behavior by appealing to evolution
  • But that does not ground self-sacrificial morality, such as what occurs in the Christian life

Brierley:

  • Dawkins says there is no purpose or morality in in the universe, do you agree?

Krauss:

  • “There is certainly no evidence of any of that”

Brierley:

  • In the book, you talk about how we live in a special time in the universe’s history to be able to do science, (i.e. – The Privileged Planet hypothesis)
  • You also write about how all the discoveries were are making will not be communicated to anyone in other places in the universe
  • So what is the meaning of doing science on your view? And why are you sad at the knowledge that will not be available to people in the future?
  • Are you longing for some kind of purpose?

Krauss:

  • No, I just get enjoyment from studying the universe with science to gain understanding

Holder:

  • What do you make of Einstein’s statement about the unexpected comprehensibility of the universe
  • Theists would say that this is because God wanted us to study and understand and gain knowledge

Krauss:

  • “It is remarkable that the universe is comprehensible”

Brierley:

  • Why is the universe comprehensible?

Krauss:

  • Well, maybe the universe just has to be that way

Brierley:

  • What do you make of the heat death of the universe, when all life in the universe will die out?

Krauss:

  • That’s the way the universe is
=== BREAK ===

Krauss:

  • I wouldn’t want to live in a universe where there was a God
  • God is a cosmic Saddam Hussein
  • “Religious people turn their minds off” and believe in God for consolation

Holder:

  • First, Jesus is the revelation of God and he is no Saddam Hussein
  • Second, the Christian life is anything but easy, we are facing some persecution already in the UK
  • Third, there is also the problem of being accountable to God when we die
  • It’s very much like science – Christianity is the way it is, not the way we want it to be

Krauss:

  • “If you don’t believe in him, you don’t get any of the benefits, so you have to believe”
  • “And then if you’ve done something wrong, you’re going to be judged for it”
  • “So I don’t want to be judged by God, I want to be… that’s the bottom line”

Holder:

  • Well, Jesus has died to pay the price for those things we’ve done wrong
  • Although we will have to face the charges for what we’ve done, believers will ultimately be forgiven

UPDATE: Peter Sean Bradley note that Krauss is now walking back his rhetoric in response to criticisms from people like atheist John Horgan.

Related posts

News

Scientists discover that tides affect a planet’s habitability

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Circumstellar Habitable Zone
Circumstellar Habitable Zone

Science Daily reports on a new factor that affects planetary habitability: tides. Specifically, tides can affect the surface temperature of a planet, which has to be within a certain range in order to support liquid water – a requirement for life of any conceivable kind.

Excerpt:

Tides can render the so-called “habitable zone” around low-mass stars uninhabitable. This is the main result of a recently published study by a team of astronomers led by René Heller of the Astrophysical Institute Potsdam.

[…]Until now, the two main drivers thought to determine a planet’s temperature were the distance to the central star and the composition of the planet’s atmosphere. By studying the tides caused by low-mass stars on their potential earth-like companions, Heller and his colleagues have concluded that tidal effects modify the traditional concept of the habitable zone.

Heller deduced this from three different effects. Firstly, tides can cause the axis of a planet`s rotation to become perpendicular to its orbit in just a few million years. In comparison, Earth’s axis of rotation is inclined by 23.5 degrees — an effect which causes our seasons. Owing to this effect, there would be no seasonal variation on such Earth-like planets in the habitable zone of low-mass stars. These planets would have huge temperature differences between their poles, which would be in perpetual deep freeze, and their hot equators which in the long run would evaporate any atmosphere. This temperature difference would cause extreme winds and storms.

The second effect of these tides would be to heat up the exoplanet, similar to the tidal heating of Io, a moon of Jupiter that shows global vulcanism.

Finally, tides can cause the rotational period of the planet (the planet’s “day”) to synchronize with the orbital period (the planet’s “year”). This situation is identical to the Earth-moon setup: the moon only shows Earth one face, the other side being known as “the dark side of the moon.” As a result one half of the exoplanet receives extreme radiation from the star while the other half freezes in eternal darkness.

The habitable zone around low-mass stars is therefore not very comfortable — it may even be uninhabitable.

Here is my previous post on the factors needed for a habitable planet. Now we just have one more. I actually find this article sort of odd, because my understanding of stars was that only high-mass stars could support life at all. This is because if the mass of the planet was too low, the habitable zone wouldbe very close to the star. Being too close to the star causes tidal locking, which means that the planet doesn’t spin on its axis at all, and the same side faces the star. This is a life killer.

This astrophysicist who teaches at the University of Wisconsin explains it better than me.

Excerpt:

Higher-mass stars tend to be larger and luminous than their lower-mass counterparts. Therefore, their habitable zones are situated further out. In addition, however, their HZs are much broader. As an illustration,

  • a 0.2 solar-mass star’s HZ extends from 0.1 to 0.2 AU
  • a 1.0 solar-mass star’s HZ extends from 1 to 2 AU
  • a 40 solar-mass star’s HZ extends from 350 to 600 AU

On these grounds, it would seem that high-mass starts are the best candidates for finding planets within a habitable zone. However, these stars emit most of their radiation in the far ultraviolet (FUV), which can be highly damaging to life, and also contributes to photodissociation and the loss of water. Furthermore, the lifetimes of these stars is so short (around 10 million years) that there is not enough time for life to begin.

Very low mass stars have the longest lifetimes of all, but their HZs are very close in and very narrow. Therefore, the chances of a planet being formed within the HZ are small. Additionally, even if a planet did form within the HZ, it would become tidally locked, so that the same hemisphere always faced the star. Even though liquid water might exist on such a planet, the climactic conditions would probably be too severe to permit life.

In between the high- and low-mass stars lie those like our own Sun, which make up about 15% percent of the stars in the galaxy. These have reasonably-broad HZs, do not suffer from FUV irradiation, and have lifetimes of the order of 10 billion years. Therefore, they are the best candidates for harbouring planets where life might be able to begin.

This guy is just someone I found through a web search. He has a support-the-unions-sticker on his web page, so he’s a liberal crackpot. But he makes my point, anyway, so that’s good enough for me.

Maybe the new discovery is talking about this now, but I already knew about the tides and habitability, because I watched The Privileged Planet DVD. Actually that whole video is online, and the clip that talks about the habitable zone and water is linked in this blog post I wrote before.