Tag Archives: Reasons to Believe

Podcasts

Two astrophysicists dialog: Hugh Ross and Paul Davies on Unbelievable

Leave a comment

Here’s the description from the Unbelievable page:

Hugh Ross is an astronomer and founder of Reasons To Believe, an apologetics organisation aiming to show why modern science confirms and supports the Christian worldview. Paul Davies is a British astrophysicist and popular science author currently based at Arizona State University. An agnostic, much of his writing has focussed on the extraordinary “fine tuning” of the Universe that allows life to exist and why the universe’s order and intelligibility defy a purely naturalistic explanation. Hugh and Paul discuss whether the properties of our Universe may be the result of a creator God, competing hypotheses such as the multiverse, whether science can be used to test the Biblical worldview… and Hugh explains why he wants NASA to look for fossils on the moon.

The MP3 file is here.

Paul Davies is one of the scientists that William Lane Craig often quotes in his debates.

Like this quote for the cosmological argument:

The evidence for the Big Bang theory of the origin of the universe points to the creation of the universe out of nothing.  Not just matter and energy, but physical space and time themselves come into existence at the Big Bang.  In the words of the British physicist P. C. W. Davies, ‘the big bang represents the creation event; the creation not only of all the matter and energy in the universe, but also of spacetime itself.’

Or this quote for the fine-tuning argument :

British physicist P. C. W. Davies has calculated that the odds against the initial conditions being suitable for later star formation (without which planets could not exist) is one followed by a thousand billion billion zeroes, at least.  He also estimates that a change in the strength of gravity or of the weak force by only one part in 10100 would have prevented a life-permitting universe.

It’s interesting that Craig chooses non-theistic scientists as sources to support his premises.

By the way, did you know that Unbelievable is having a conference later this month? Click here to find out about it, especially if you like science apologetics.

Podcasts

Brian Auten interviews astrophysicist Jeff Zweerink about the multiverse

1 Comment

Brian Auten of Apologetics 315 has a new interview with Jeff Zweerink on the multiverse.

Brian’s summary:

Today’s interview is with astrophysicist Jeff Zweerink. Jeff is a research scholar with Reasons to Believe, and serves part-time on the physics and astronomy research faculty at UCLA. He is author of Who’s Afraid of the Multiverse?, the main topic of our interview today. He talks about his background and how he got into astrophysics, scientific evidences pointing to God, the role of natural theology, the strongest (and weakest) arguments from science, the multiverse, the various types of multiverses, why scientists postulate the multiverse, various objections to the multiverse, should Christians, how to be well-informed in scientific evidences, advice for apologists, and more.

Full Interview MP3 Audio here (55 min)

Krista Bontrager writes this about Jeff’s book:

Reasons To Believe has a new booklet out. It addresses the multiverse controversy: Who’s Afraid of the Multiverse? (And when I say “booklet” it would really be more accurate to call it a short book. It’s a “good-sized” short treatment.)

RTB’s newest research scholar, physicist, Dr. Jeff Zweerink, explores the multiverse idea and its implications for biblical creation models. He addresses such questions as:

  • Does the multiverse pose problems for the Christian worldview?
  • Does the multiverse offer atheists an escape-hatch, one that is capable of explaining away design of the universe?

Zweerink’s answers to these questions may surprise some readers. He believes it is quite possible that particular types of multiverses to exist. (Whereas I think it would be fair to characterize Hugh Ross as being a little more cautious about this issue.)

Zweerink does a good job of explaining the appeal of the multiverse approach for some athetists. In fact, he is so fair and even-handed that, at times, the reader may wonder whether he’s defending the multiverse in all of its forms.

I am not aware of any other treatment of this quality by a Christian physicist. If you have a teenager who is planning on a career in science, especially in astronomy or physics, Who’s Afraid of the Multiverse? is a must-read. It would probably also be of interest to those who are curious about the topic.

It sounds like Jeff actually is open to the multiverse. BOOOO! James Sinclair’s essay in Contending With Christianity’s Critics also seemed to give the idea a fair treatment. Oh well, I have to be open to being proven wrong, so here is the podcast and let’s see the evidence!

Commentary

What are galactic habitable zones and circumstellar habitable zones?

1 Comment

The Circumstellar Habitable Zone (CHZ)

What do you need in order to have a planet that supports complex life? First, you need liquid water at the surface of the planet. But there is only a narrow range of temperatures that can support liquid water. It turns out that the size of the star that your planet orbits around has a lot to do with whether you get liquid water or not. A heavy, metal-rich star allows you to have a habitable planet far enough from the star so  the planet can support liquid water on the planet’s surface while still being able to spin on its axis. The zone where a planet can have liquid water at the surface is called the circumstellar habitable zone (CHZ). A metal-rich star like our Sun is very massive, which moves the habitable zone out further away from the star. If our star were smaller, we would have to orbit much closer to the star in order to have liquid water at the surface. Unfortunately, if you go too close to the star, then your planet becomes tidally locked, like the moon is tidally locked to Earth. Tidally locked planets are inhospitable to life.

Circumstellar Habitable Zone
Circumstellar Habitable Zone

Here, watch a clip from The Privileged Planet: (Clip 4 of 12, full playlist here)

But there’s more.

The Galactic Habitable Zone (GHZ)

So, where do you get the heavy elements you need for your heavy metal-rich star?

You have to get the heavy elements for your star from supernova explosions – explosions that occur when certain types of stars die. That’s where heavy elements come from. But you can’t be TOO CLOSE to the dying stars, because you will get hit by nasty radiation and explosions. So to get the heavy elements from the dying stars, your solar system needs to be in the galactic habitable zone (GHZ) – the zone where you can pickup the heavy elements you need but not get hit by radiation and explosions. The GHZ lies between the spiral arms of a spiral galaxy. Not only do you have to be in between the arms of the spiral galaxy, but you also cannot be too close to the center of the galaxy. The center of the galaxy is too dense and you will get hit with massive radiation that will break down your life chemistry. But you also can’t be too far from the center, because you won’t get enough heavy elements because there are fewer dying stars the further out you go. You need to be in between the spiral arms, a medium distance from the center of the galaxy.

Like this:

Galactic Habitable Zone
Galactic Habitable Zone and Solar Habitable Zone

Here, watch a clip from The Privileged Planet: (Clip 10 of 12, full playlist here)

The GHZ is based on a discovery made by astronomer Guillermo Gonzalez, which made the front cover of Scientific American in 2001. That’s right, the cover of Scientific American. I actually stole the image above of the GHZ and CHZ (aka solar habitable zone) from his Scientific American article (linked above).

These are just a few of the things you need in order to get a planet that supports life.

Here are a few of the more well-known ones:

  • a solar system with a single massive Sun than can serve as a long-lived, stable source of energy
  • a terrestrial planet (non-gaseous)
  • the planet must be the right distance from the sun in order to preserve liquid water at the surface – if it’s too close, the water is burnt off in a runaway greenhouse effect, if it’s too far, the water is permanently frozen in a runaway glaciation
  • the solar system must be placed at the right place in the galaxy – not too near dangerous radiation, but close enough to other stars to be able to absorb heavy elements after neighboring stars die
  • a moon of sufficient mass to stabilize the tilt of the planet’s rotation
  • plate tectonics
  • an oxygen-rich atmosphere
  • a sweeper planet to deflect comets, etc.
  • planetary neighbors must have non-eccentric orbits

By the way, you can watch a lecture with Guillermo Gonzalez explaining his ideas further. This lecture was delivered at UC Davis in 2007. That link has a link to the playlist of the lecture, a bio of the speaker, and a summary of all the topics he discussed in the lecture. An excellent place to learn the requirements for a suitable habitat for life.