Tag Archives: Progress of Science

Polemics

Alexander Vilenkin: “All the evidence we have says that the universe had a beginning”

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I’m hearing from atheists that the universe did not begin to exist, so I thought I’d explain why physicists can’t avoid a creation event – or rather, I’d let famous cosmologist Alexander Vilenkin do it.

From Uncommon Descent.

Excerpt:

Did the cosmos have a beginning? The Big Bang theory seems to suggest it did, but in recent decades, cosmologists have concocted elaborate theories – for example, an eternally inflating universe or a cyclic universe – which claim to avoid the need for a beginning of the cosmos. Now it appears that the universe really had a beginning after all, even if it wasn’t necessarily the Big Bang.

At a meeting of scientists – titled “State of the Universe” – convened last week at Cambridge University to honor Stephen Hawking’s 70th birthday, cosmologist Alexander Vilenkin of Tufts University in Boston presented evidence that the universe is not eternal after all, leaving scientists at a loss to explain how the cosmos got started without a supernatural creator. The meeting was reported in New Scientist magazine (Why physicists can’t avoid a creation event, 11 January 2012).

[…]In his presentation, Professor Vilenkin discussed three theories which claim to avoid the need for a beginning of the cosmos.

The three theories are chaotic inflationary model, the oscillating model and quantum gravity model. Regular readers will know that those have all been addressed in William Lane Craig’s peer-reviewed paper that evaluates alternatives to the standard Big Bang cosmology.

But let’s see what Vilenkin said.

More:

One popular theory is eternal inflation. Most readers will be familiar with the theory of inflation, which says that the universe increased in volume by a factor of at least 10^78 in its very early stages (from 10^−36 seconds after the Big Bang to sometime between 10^−33 and 10^−32 seconds), before settling into the slower rate of expansion that we see today. The theory of eternal inflation goes further, and holds that the universe is constantly giving birth to smaller “bubble” universes within an ever-expanding multiverse. Each bubble universe undergoes its own initial period of inflation. In some versions of the theory, the bubbles go both backwards and forwards in time, allowing the possibility of an infinite past. Trouble is, the value of one particular cosmic parameter rules out that possibility:

But in 2003, a team including Vilenkin and Guth considered what eternal inflation would mean for the Hubble constant, which describes mathematically the expansion of the universe. They found that the equations didn’t work (Physical Review Letters, DOI: 10.1103/physrevlett.90.151301). “You can’t construct a space-time with this property,” says Vilenkin. It turns out that the constant has a lower limit that prevents inflation in both time directions. “It can’t possibly be eternal in the past,” says Vilenkin. “There must be some kind of boundary.”

A second option explored by Vilenkin was that of a cyclic universe, where the universe goes through an infinite series of big bangs and crunches, with no specific beginning. It was even claimed that a cyclic universe could explain the low observed value of the cosmological constant. But as Vilenkin found, there’s a problem if you look at the disorder in the universe:

Disorder increases with time. So following each cycle, the universe must get more and more disordered. But if there has already been an infinite number of cycles, the universe we inhabit now should be in a state of maximum disorder. Such a universe would be uniformly lukewarm and featureless, and definitely lacking such complicated beings as stars, planets and physicists – nothing like the one we see around us.

One way around that is to propose that the universe just gets bigger with every cycle. Then the amount of disorder per volume doesn’t increase, so needn’t reach the maximum. But Vilenkin found that this scenario falls prey to the same mathematical argument as eternal inflation: if your universe keeps getting bigger, it must have started somewhere.

However, Vilenkin’s options were not exhausted yet. There was another possibility: that the universe had sprung from an eternal cosmic egg:

Vilenkin’s final strike is an attack on a third, lesser-known proposal that the cosmos existed eternally in a static state called the cosmic egg. This finally “cracked” to create the big bang, leading to the expanding universe we see today. Late last year Vilenkin and graduate student Audrey Mithani showed that the egg could not have existed forever after all, as quantum instabilities would force it to collapse after a finite amount of time (arxiv.org/abs/1110.4096). If it cracked instead, leading to the big bang, then this must have happened before it collapsed – and therefore also after a finite amount of time.

“This is also not a good candidate for a beginningless universe,” Vilenkin concludes.

So at the end of the day, what is Vilenkin’s verdict?

“All the evidence we have says that the universe had a beginning.”

This is consistent with the Borde-Guth-Vilenkin Theorem, which I blogged about before, and which William Lane Craig leveraged to his advantage in his debate with Peter Millican.

The Borde-Guth-Vilenkin (BGV) proof shows that every universe that expands must have a space-time boundary in the past. That means that no expanding universe, no matter what the model, can be eternal into the past. Even speculative alternative cosmologies do not escape the need for a beginning.

Conclusion

If the universe came into being out of nothing, which seems to be the case from science, then the universe has a cause. Things do not pop into being, uncaused, out of nothing. The cause of the universe must be transcendent and supernatural. It must be uncaused, because there cannot be an infinite regress of causes. It must be eternal, because it created time. It must be non-physical, because it created space. There are only two possibilities for such a cause. It could be an abstract object or an agent. Abstract objects cannot cause effects. Therefore, the cause is an agent.

Polemics

MIT physicist explains the challenge of cosmic fine-tuning for naturalism

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Here’s the article from Harper’s magazine.

The MIT physicist says that the fine-tuning is real, and is best explained by positing the existence of an infinite number of universes that are not fine-tuned – the so-called multiverse.

Excerpt:

While challenging the Platonic dream of theoretical physicists, the multiverse idea does explain one aspect of our universe that has unsettled some scientists for years: according to various calculations, if the values of some of the fundamental parameters of our universe were a little larger or a little smaller, life could not have arisen. For example, if the nuclear force were a few percentage points stronger than it actually is, then all the hydrogen atoms in the infant universe would have fused with other hydrogen atoms to make helium, and there would be no hydrogen left. No hydrogen means no water. Although we are far from certain about what conditions are necessary for life, most biologists believe that water is necessary. On the other hand, if the nuclear force were substantially weaker than what it actually is, then the complex atoms needed for biology could not hold together. As another example, if the relationship between the strengths of the gravitational force and the electromagnetic force were not close to what it is, then the cosmos would not harbor any stars that explode and spew out life-supporting chemical elements into space or any other stars that form planets. Both kinds of stars are required for the emergence of life. The strengths of the basic forces and certain other fundamental parameters in our universe appear to be “fine-tuned” to allow the existence of life. The recognition of this fine-­tuning led British physicist Brandon Carter to articulate what he called the anthropic principle, which states that the universe must have the parameters it does because we are here to observe it. Actually, the word anthropic, from the Greek for “man,” is a misnomer: if these fundamental parameters were much different from what they are, it is not only human beings who would not exist. No life of any kind would exist.

If such conclusions are correct, the great question, of course, is why these fundamental parameters happen to lie within the range needed for life. Does the universe care about life? Intelligent design is one answer. Indeed, a fair number of theologians, philosophers, and even some scientists have used fine-tuning and the anthropic principle as evidence of the existence of God. For example, at the 2011 Christian Scholars’ Conference at Pepperdine University, Francis Collins, a leading geneticist and director of the National Institutes of Health, said, “To get our universe, with all of its potential for complexities or any kind of potential for any kind of life-form, everything has to be precisely defined on this knife edge of improbability…. [Y]ou have to see the hands of a creator who set the parameters to be just so because the creator was interested in something a little more complicated than random particles.”

Intelligent design, however, is an answer to fine-tuning that does not appeal to most scientists. The multiverse offers another explanation. If there are countless different universes with different properties—for example, some with nuclear forces much stronger than in our universe and some with nuclear forces much weaker—then some of those universes will allow the emergence of life and some will not. Some of those universes will be dead, lifeless hulks of matter and energy, and others will permit the emergence of cells, plants and animals, minds. From the huge range of possible universes predicted by the theories, the fraction of universes with life is undoubtedly small. But that doesn’t matter. We live in one of the universes that permits life because otherwise we wouldn’t be here to ask the question.

I thought I was going to have to go outside this article to refute the multiverse, but Lightman is honest enough to refute it himself:

The… conjecture that there are many other worlds… [T]here is no way they can prove this conjecture. That same uncertainty disturbs many physicists who are adjusting to the idea of the multiverse. Not only must we accept that basic properties of our universe are accidental and uncalculable. In addition, we must believe in the existence of many other universes. But we have no conceivable way of observing these other universes and cannot prove their existence. Thus, to explain what we see in the world and in our mental deductions, we must believe in what we cannot prove.

Sound familiar? Theologians are accustomed to taking some beliefs on faith. Scientists are not. All we can do is hope that the same theories that predict the multiverse also produce many other predictions that we can test here in our own universe. But the other universes themselves will almost certainly remain a conjecture.

The multiverse is not pure nonsense, it is theoretically possible. The problem is that the multiverse generator itself would require fine-tuning, so the multiverse doesn’t get rid of the problem. And, as Lightman indicates, we have no independent experimental evidence for the existence of the multiverse in any case. Atheists just have to take it on faith, and hope that their speculations will be proved right. Meanwhile, the fine-tuning is just as easily explained by postulating God, and we have independent evidence for God’s existence, like the the origin of biological information, the sudden appearance of animal body plans, the argument from consciousness, and so on. Even if the naturalists could explain the fine-tuning, they would still have a lot of explaining to do. Theism (intelligent causation) is the simplest explanation for all of the things we learn from the progress of science.

We need to be frank about atheists and their objections to the progress of science. Within the last 100 years, we have discovered that the physical universe came into being out of nothing 15 billion years ago, and we have discovered that this one universe is fine-tuned for intelligent life. I don’t think it’s like that the last 100 years of scientific progress on the origins question are going to be overturned so that science once again affirms what atheists believe about the universe. Things are going the wrong way for atheists – at least with respect to science.

See it in action

To see these arguments examined in a debate with a famous atheist, simply watch the debate between William Lane Craig and Christopher Hitchens, and judge which debater is willing to form his beliefs on scientific progress, and which debater is forming his beliefs against the science we have today, and hoping that the good science we have today based on experiments will be overturned by speculative theories at some point in the future. When you watch that debate, it becomes very clear that Christian theists are interested in conforming their beliefs to science, and atheists are very interested in speculating against what science has shown in order to maintain their current pre-scientific view. That’s not what rational people ought to do when confronted with evidence.

Positive arguments for Christian theism

Videos

William Lane Craig lectures on naturalistic alternatives to the Big Bang

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Here’s the lecture, which was given in 2004 at the University of Colorado, Boulder. A very liberal university!

This lecture might be a little advanced for beginners, but if you stretch your mind first, you shouldn’t tear anything. (Note: standard disclaimers apply if you do tear something!)

The description of the video states:

This is quite simply one of the best lectures William Lane Craig (a philosopher of science) has given. Craig explores the origins of the universe. He argues for a beginning of the universe, while refuting scientific models like the Steady State Theory, the Oscillating Theory, Quantum Vacuum Fluctuation Model, Chaotic Inflationary Theory, Quantum Gravity Theory, String Theory, M-Theory and Cyclic Ekpyrotic Theory.

And here is the description of the lecture from Reasonable Faith:

A Templeton Foundation lecture at the University of Colorado, Boulder, laying out the case from contemporary cosmology for the beginning of the universe and its theological implications. Includes a lengthy Q & A period which features previous critics and debate opponents of Dr. Craig who were in attendance, including Michael Tooley, Victor Stenger, and Arnold Guminski.

Craig has previously debated famous atheists Stenger and Tooley previously. And they both asked him questions in the Q&A time of this lecture. Imagine – having laid out your entire case to two people who have debated you before and who know your arguments well. What did they ask Craig, and how did he respond?

The scientific evidence

The Big Bang cosmology that Dr. Craig presents is the standard model for how the universe came into being. It is a theory based on six lines of experimental evidence.

Scientific evidence:

  1. Einstein’s theory of general relativity (GTR)
  2. the red-shifting of light from distant galaxies implies an expanding universe
  3. the cosmic background radiation (which also disproves the oscillating model of the universe)
  4. the second law of thermodynamics applied to star formation theory
  5. hydrogen-helium abundance predictions
  6. radioactive element abundance predictions

If you are looking for some detail on these evidences, here’s a re-cap of the three main evidences for the Big Bang cosmology from Caltech. (Numbers 2, 3 and 5 from the list above)

Excerpt:

Until the early 1900s, most people had assumed that the universe was fixed in size. New possibilities opened up in 1915, when Einstein formulated his famous general relativity theory that describes the nature of space, time, and gravity. This theory allows for expansion or contraction of the fabric of space. In 1917, astronomer Willem de Sitter applied this theory to the entire universe and boldly went on to show that the universe could be expanding. Aleksandr Friedmann, a mathematician, reached the same conclusion in a more general way in 1922, as did Georges Lemaître, a cosmologist and a Jesuit, in 1927. This step was revolutionary since the accepted view at the time was that the universe was static in size. Tracing back this expanding universe, Lemaître imagined all matter initially contained in a tiny universe and then exploding. These thoughts introduced amazing new possibilities for the universe, but were independent of observation at that time.

[…]Three main observational results over the past century led astronomers to become certain that the universe began with the big bang. First, they found out that the universe is expanding—meaning that the separations between galaxies are becoming larger and larger. This led them to deduce that everything used to be extremely close together before some kind of explosion. Second, the big bang perfectly explains the abundance of helium and other nuclei like deuterium (an isotope of hydrogen) in the universe. A hot, dense, and expanding environment at the beginning could produce these nuclei in the abundance we observe today. Third, astronomers could actually observe the cosmic background radiation—the afterglow of the explosion—from every direction in the universe. This last evidence so conclusively confirmed the theory of the universe’s beginning that Stephen Hawking said, “It is the discovery of the century, if not of all time.”

It’s probably a good idea to be familiar with these if you are presenting this argument, because experimental science is a reliable way of knowing about reality.

Published research paper

This lecture by Dr. Craig is based on a research paper published in an astrophysics journal, and was delivered to an audience of students and faculty, including atheist physicist Victor Stenger and prominent atheist philosopher Michael Tooley, at the University of Colorado at Boulder.

Here’s the peer-reviewed article that the lecture is based on.

Here’s the abstract:

Both cosmology and philosophy trace their roots to the wonder felt by the ancient Greeks as they contemplated the universe. The ultimate question remains why the universe exists rather than nothing. This question led Leibniz to postulate the existence of a metaphysically necessary being, which he identified as God. Leibniz’s critics, however, disputed this identification, claiming that the space-time universe itself may be the metaphysically necessary being. The discovery during this century that the universe began to exist, however, calls into question the universe’s status as metaphysically necessary, since any necessary being must be eternal in its existence. Although various cosmogonic models claiming to avert the beginning of the universe predicted by the standard model have been and continue to be offered, no model involving an eternal universe has proved as plausible as the standard model. Unless we are to assert that the universe simply sprang into being uncaused out of nothing, we are thus led to Leibniz’s conclusion. Several objections to inferring a supernatural cause of the origin of the universe are considered and found to be unsound.

The whole text of the article is posted online here.

If you want something to post on your Twitter or Facebook that is much shorter than this lecture, then you should check out this quick 4-minute explanation of the kalam argument.