Here’s a short article from the Massachusetts Institute of Technology’s Physics arXiv blog. (H/T Wes)
Excerpt:
The Big Bang has become part of popular culture since the phrase was coined by the maverick physicist Fred Hoyle in the 1940s. That’s hardly surprising for an event that represents the ultimate birth of everything.
However, Hoyle much preferred a different model of the cosmos: a steady state universe with no beginning or end, that stretches infinitely into the past and the future. That idea never really took off.
In recent years, however, cosmologists have begun to study a number of new ideas that have similar properties. Curiously, these ideas are not necessarily at odds with the notion of a Big Bang.
For instance, one idea is that the universe is cyclical with big bangs followed by big crunches followed by big bangs in an infinite cycle.
Another is the notion of eternal inflation in which different parts of the universe expand and contract at different rates. These regions can be thought of as different universes in a giant multiverse.
So although we seem to live in an inflating cosmos, other universes may be very different. And while our universe may look as if it has a beginning, the multiverse need not have a beginning.
Then there is the idea of an emergent universe which exists as a kind of seed for eternity and then suddenly expands.
So these modern cosmologies suggest that the observational evidence of an expanding universe is consistent with a cosmos with no beginning or end. That may be set to change.
Today, Audrey Mithani and Alexander Vilenkin at Tufts University in Massachusetts say that these models are mathematically incompatible with an eternal past. Indeed, their analysis suggests that these three models of the universe must have had a beginning too.
Their argument focuses on the mathematical properties of eternity–a universe with no beginning and no end. Such a universe must contain trajectories that stretch infinitely into the past.
However, Mithani and Vilenkin point to a proof dating from 2003 that these kind of past trajectories cannot be infinite if they are part of a universe that expands in a specific way.
They go on to show that cyclical universes and universes of eternal inflation both expand in this way. So they cannot be eternal in the past and must therefore have had a beginning. “Although inflation may be eternal in the future, it cannot be extended indefinitely to the past,” they say.
They treat the emergent model of the universe differently, showing that although it may seem stable from a classical point of view, it is unstable from a quantum mechanical point of view. “A simple emergent universe model…cannot escape quantum collapse,” they say.
The conclusion is inescapable. “None of these scenarios can actually be past-eternal,” say Mithani and Vilenkin.
Since the observational evidence is that our universe is expanding, then it must also have been born in the past. A profound conclusion (albeit the same one that lead to the idea of the big bang in the first place).
They link to this peer-reviewed paper featuring Alexander Vilenkin at the end of the article, which was published in the Proceedings of the 10th Incternational Conference on Gravitation, Astrophysics and Cosmology, Quy-Nhon, Vietnam, December 2011.
The paper concludes:
Did the universe have a beginning?
At this point, it seems that the answer to this question is probably yes. Here we have addressed three scenarios which seemed to offer a way to avoid a beginning, and have found that none of them can actually be eternal in the past. Both eternal inflation and cyclic universe scenarios have Hav > 0, which means that they must be past-geodesically incomplete. We have also examined a simple emergent universe model, and concluded that it cannot escape quantum collapse. Even considering more general emergent universe models, there do not seem to be any matter sources that admit solutions that are immune to collapse.
So where do we stand? There is no eternal universe. There was a beginning to space and time. The entire physical universe came into being out of nothing at some point in the past.
Here’s my previous post on the BVG theorem that explains a bit more about how this data applies to the question of God’s existence.
The OSU [Oregon State University] Socratic Club will sponsor a public dialogue entitled, “Two Philosophers Debate the Existence of God,” on Monday, March 1, at 7 p.m. in the LaSells Stewart Center on the OSU campus. William Lane Craig will argue for the Christian view that a personal God exists and Victor J. Stenger the atheist position that there is no God.
In this debate, Victor Stenger does affirm his belief that the universe could be eternal in his second rebuttal (1:02:30), thus denying the standard Big Bang cosmology. He also denies the law of conservation of energy and asserts that something can come from nothing in his concluding speech (1:33:50). He also caused the audience to start laughing when he said that Jesus was not moral and supported slavery. There is almost no snark in this summary. Instead, I quoted Dr. Stenger verbatim in many places. I still think that it is very entertaining even without the snarky paraphrasing.
The debate includes 30 minutes of Q&A with the students.
There is no scientific evidence for God’s existence in the textbooks
There is no scientific evidence for God acting in the universe
God doesn’t talk to people and tell them things they couldn’t possibly know
The Bible says that the Earth is flat, etc.
There is no scientific evidence that God answers prayers
God doesn’t exist because people who believe in him are ignorant
Human life is not optimally designed and appears to be the result of a blind, ad hoc evolutionary process
The beginning of the universe is not ordered (low entropy) but random and chaotic
It’s theoretically possible that quantum tunneling explains the origin of the universe
The laws of physics are not objectively real, they are “our inventions”
Regarding the beginning of the universe, the explanation is that something came from nothing*
Nothing* isn’t really nothing, it is “the total chaos that we project existed just before the big bang”
If something has no structure, then “it is as much nothing as nothing can be”
Consciousness is explainable solely on the basis of material processes
There are well-informed, rational non-believers in the world and God would not allow that
Dr. Craig’s first rebuttal:
Stenger’s argument that there is no objective evidence for God’s existence:
First, it is not required that God rely only on objective evidence in order to draw people to himself (Alvin Plantinga)
Second, God is not required to provide evidence to everyone, only to the people who he knows would respond to him
Third, Craig gave lots of objective evidence, from science, history and philosophy
Stenger asks for certain evidence (answered prayers, prophecy, etc.), but Craig presented the evidence we have
Stenger’s argument that the balance of energy is zero so “nothing” exists:
if you have the same amount of assets and liabilities, it doesn’t mean that nothing exists – your assets and liabilities exist
Christopher Isham says that there needs to be a cause to create the positive and negative energy even if they balance
the quantum gravity model contradicts observations
the vacuum is not the same as nothing, it contains energy and matter
the BVG theorem proves that any universe that is expanding must have a beginning
Stenger’s argument that mental operations can be reduced to physical operations:
mental properties are not reducible to physical properties
epiphenomenalism: is incompatible with self-identity over time
epiphenomenalism: is incompatible with thoughts about other things
epiphenomenalism: is incompatible with free will
substance dualism (mind/body dualism) is a better explanation for our mental experience
God is a soul without a body
Dr. Stenger’s first rebuttal:
Craig’s cosmological argument:
Craig’s premise is “everything has a cause”, but quantum mechanics has causeless events
There are speculative theories about how something could have come into being uncaused out of nothing
“I don’t know of a single working cosmologist today who believes there was a singularity prior to the Big Bang”
“If there wasn’t a singularity then there’s no basis for arguing that time began at that point”
“There’s no reason from cosmology that we know of that the universe can’t be eternal”
“When I talk about an eternal universe, I mean a universe that has no beginning or end”
The Hartle-Hawking model doesn’t have a beginning
“There was no violation of energy conservation by having a universe coming from nothing”
“The universe could have come from a previous universe for example or even just from a region of chaos”
The paper by Vilenkin is counteracted by other papers (he doesn’t specify which ones)
Craig’s moral argument:
Dr. Craig is arguing from ignorance
But morality can be decided by humanity just like governments pass laws, and that’s objective
Dr. Craig has too little respect for the human intellect
I don’t need to tell me that slavery is wrong
The Bible supports slavery
Atheists can behave as good as theists
Morality just evolved naturally as an aid to survival
Craig’s resurrection argument:
No Roman historians wrote about the execution of Jesus but none of them did
The empty tomb is doubtful because it is only mentioned in the gospels, not by Paul
John Dominic Crossan says there was no empty tomb
Christianity only survived because the Roman empire thought that they were useful
Dr. Craig’s second rebuttal:
Craig’s cosmological argument:
There is no reason to prefer an indeterministic interpretation of quantum mechanics
Dr. Stenger himself wrote that deterministic interpretations of quantum mechanics are possible
The vacuum in quantum mechanics is not nothing
The quantum vacuum he proposes cannot be eternal
The cosmological argument does not require a singularity
The Hartle-Hawking model is from 1983
Hawking says that there is a beginning of space and time after that model
The Hartle-Hawking model does still have a beginning of time – the model is not eternal
The BVG theorem that requires a beginning for expanding universes is widely accepted among cosmologists
Craig’s moral argument:
Stenger redefined objective to mean that most people agree with it – but that’s not what objective means
Objective means right and wrong whether anyone accepts it or not
Richard Dawkins himself says that on atheism there is “no evil and no good” – why is he wrong?
Even Dr. Stenger says that morality is the same as passing laws – it’s arbitrary and varies by time and place
But on his view, right and wrong are the same as deciding which side of the road to drive on
But somethings really are right and some things are really wrong
Craig’s resurrection argument:
Josephus is a Roman historian and he wrote about Jesus, for example
There were four biographies of Jesus are the best sources for his life
The scholars that Stenger mentioned are on the radical fringe
Dr. Stenger’s second rebuttal:
Knowledge and the burden of proof:
Dr. Craig has to bear the burden of proof, not me – because his claim is more “extravagant”
“I don’t have to prove that a God was not necessary to create the universe”
“I don’t have to prove that a God did not design the universe and life”
“I don’t have to prove that the universe did not have a beginning”
“I don’t have to prove that God did not provide us with our moral sense”
There are a lot of books written about how morality evolved naturally
“I don’t have to prove that the events surrounding the supposed resurrection of Jesus did not take place”
Bart Ehrman says that the gospels are generally unreliable (Note: Ehrman accepts all 3 of Craig’s minimal facts)
Just because people are willing to die for a cause, does not make their leader God, e.g. – the Emperor of Japan
Aesthetic concerns about the universe:
I don’t like dark matter and I wouldn’t have made the universe with dark matter
I don’t like the doctrine of penal substitution
I don’t like the doctrine of original sin
I don’t like the heat death of the universe
Dr. Craig’s conclusion:
The case for atheism:
Dr. Stenger had two arguments and he has to support his premises
Dr. Craig addressed his two arguments and each premise and Dr. Stenger never came back on it
The contingency argument:
Dr. Stenger has dropped the refutation of this argument
The cosmological argument:
The theoretical vacuum he proposes cannot be eternal
The moral argument:
He asserts that things are wrong, but there is no grounding for that to be objective on atheism
The resurrection of Jesus:
There are surveys of scholars on the empty tomb and 75% of them agree with it
Bart Ehrman agrees with all 3 of the minimal facts that Dr. Craig presented
Ehrman’s objection to the resurrection is not historical: he’s an atheist – he thinks miracles are impossible
Religious experience:
No response from Dr. Stenger
Dr. Stenger’s conclusion
The cosmological argument:
“I argued that we have very good physical reasons to understand how something can come from nothing”
“There is a natural tendency in the universe… to go from.. simpler thing to the more complicated thing”
The transition from a vapor to a liquid to ice shows how something could come from nothing
“It cannot be proven that the universe had a beginning”
The moral argument:
Objective morality, which is independent of what people think, could be developed based on what people think
“Jesus himself was not a tremendously moral person… he had no particular regard for the poor… he certainly supported slavery… he was for the subjugation of women” (audience laughter)
The resurrection argument:
Bart Ehrman says that the majority of the gospels are unreliable
Religious experience:
I don’t see any evidence that there is anything more to religious experience than just stuff in their heads
God’s purpose of the world should be to make people feel happy:
God could have made people feel happier
God could have made people not die
God could could have made the universe smaller: it’s too big
God could have made it possible for humans to live anywhere “even in space”
Victor Stenger is a famous “Internet Infidel” atheist, but what makes him different is that he is has a PhD in physics. He wrote a book published by the atheist publisher Prometheus Press where he explains why he thinks that the universe is not fine-tuned for embodied sentient life.
An Australian physicist named Luke Barnes decided to write a response to his book, and the response is summarized (without the math!) on Uncommon Descent. Barnes has a PhD in Astronomy from Cambridge. He did postdoctoral research in Switzerland at the Institute for Astonomy, and now he is doing more postdoctoral research at the University of Sydney . The response that he wrote does not talk about God, or explanations of why the fine-tuning happened. I have no idea where his convictions are on any of that, because his response just talks about the fine-tuning itself from a scientific point of view.
Professor Victor Stenger is an American particle physicist and a noted atheist, who popularized the phrase, “Science flies you to the moon. Religion flies you into buildings”. Professor Stenger is also the author of several books, including his recent best-seller, The Fallacy of Fine-Tuning: How the Universe is Not Designed for Humanity (Prometheus Books, 2011). Stenger’s latest book has been received with great acclaim by atheists: “Stenger has demolished the fine-tuning proponents,” writes one enthusiastic Amazon reviewer, adding that the book tells us “how science is able to demonstrate the non-existence of god.”
Well, it seems that the great Stenger has finally met his match. Dr. Luke A. Barnes, a post-doctoral researcher at the Institute for Astronomy, ETH Zurich, Switzerland, has written a scathing critique of Stenger’s book. I’ve read refutations in my time, but I have to say, this one is devastating.
In his paper, Dr. Barnes takes care to avoid drawing any metaphysical conclusions from the fact of fine-tuning. He has no religious axe to grind. His main concern is simply to establish that the fine-tuning of the universe is real, contrary to the claims of Professor Stenger, who asserts that all of the alleged examples of fine-tuning in our universe can be explained without the need for a multiverse.
Dr. Barnes’ ARXIV paper, The Fine-Tuning of the Universe for Intelligent Life (Version 1, December 21, 2011), is available online, and I shall be quoting from it below. Since the paper is quite technical at times, I’ve omitted mathematical equations and kept the references to physical parameters to a minimum, since I simply wish to give readers an overview of what Dr. Barnes perceives as the key flaws in Professor Stenger’s book.
First, the abstract:
The fine-tuning of the universe for intelligent life has received a great deal of attention in recent years, both in the philosophical and scientific literature. The claim is that in the space of possible physical laws, parameters and initial conditions, the set that permits the evolution of intelligent life is very small. I present here a review of the scientific literature, outlining cases of fine-tuning in the classic works of Carter, Carr and Rees, and Barrow and Tipler, as well as more recent work. To sharpen the discussion, the role of the antagonist will be played by Victor Stenger’s recent book The Fallacy of Fine-Tuning: Why the Universe is Not Designed for Us. Stenger claims that all known fine-tuning cases can be explained without the need for a multiverse. Many of Stenger’s claims will be found to be highly problematic. We will touch on such issues as the logical necessity of the laws of nature; objectivity, invariance and symmetry; theoretical physics and possible universes; entropy in cosmology; cosmic inflation and initial conditions; galaxy formation; the cosmological constant; stars and their formation; the properties of elementary particles and their effect on chemistry and the macroscopic world; the origin of mass; grand unified theories; and the dimensionality of space and time. I also provide an assessment of the multiverse, noting the significant challenges that it must face. I do not attempt to defend any conclusion based on the fine-tuning of the universe for intelligent life. This paper can be viewed as a critique of Stenger’s book, or read independently.
Here’s a quote that I wanted to put out there from the paper about how widely accepted fine-tuning is among scientists:
There are a great many scientists, of varying religious persuasions, who accept that the universe is fine-tuned for life, e.g. Barrow, Carr, Carter, Davies, Dawkins, Deutsch, Ellis, Greene, Guth, Harrison, Hawking, Linde, Page, Penrose, Polkinghorne, Rees, Sandage, Smolin, Susskind, Tegmark, Tipler, Vilenkin, Weinberg, Wheeler, Wilczek. They differ, of course, on what conclusion we should draw from this fact. Stenger, on the other hand, claims that the universe is not fine-tuned.
That is a very diverse list. I know that Sandage, Ellis, Page, Tipler and Polkinghorne are theists. But I also know that Weinberg, Rees, Hawking, Greene, and Dawkins are atheists. So scientists all across the spectrum of worldview admit that the fine-tuning is real.
Now, let’s look at Barnes’ paper and see why Victor Stenger disagrees with the view of those scientists.
1) Stenger doesn’t show why the entropy at the beginning of the universe isn’t a case of fine-tuning:
Entropy
We turn now to cosmology. The problem of the apparently low entropy of the universe is one of the oldest problems of cosmology. The fact that the entropy of the universe is not at its theoretical maximum, coupled with the fact that entropy cannot decrease, means that the universe must have started in a very special, low entropy state. (p. 23)
Let’s return to Stenger’s proposed solution… Stenger takes it for granted that the universe is homogeneous and isotropic. We can see this also in his use of the Friedmann equation, which assumes that space-time is homogeneous and isotropic. Not surprisingly, once homogeneity and isotropy have been assumed, Stenger finds that the solution to the entropy problem is remarkably easy.
We conclude that Stenger has not only failed to solve the entropy problem; he has failed to comprehend it. He has presented the problem itself as its solution. Homogeneous, isotropic expansion cannot solve the entropy problem – it is the entropy problem. Stenger’s assertion that “the universe starts out with maximum entropy or complete disorder” is false. A homogeneous, isotropic spacetime is an incredibly low entropy state. Penrose (1989) warned of precisely this brand of failed solution two decades ago... (p. 26)
2) Stenger responds to calculations showing the need for fine-tuning by speculating that future calculations will overturn the ones we have now:
The Cosmological Constant, Lambda
The cosmological constant problem is described in the textbook of Burgess & Moore (2006) as “arguably the most severe theoretical problem in high-energy physics today, as measured by both the difference between observations and theoretical predictions, and by the lack of convincing theoretical ideas which address it”. A well-understood and well-tested theory of fundamental physics (Quantum Field Theory – QFT) predicts contributions to the vacuum energy of the universe that are [approx.] 10^120 times greater than the observed total value. Stenger’s reply is guided by the following principle:
Any calculation that disagrees with the data by 50 or 120 orders of magnitude is simply wrong and should not be taken seriously. We just have to await the correct calculation. [FOFT p. 219]
This seems indistinguishable from reasoning that the calculation must be wrong since otherwise the cosmological constant would have to be fine-tuned. One could not hope for a more perfect example of begging the question. More importantly, there is a misunderstanding in Stenger’s account of the cosmological constant problem. The problem is not that physicists have made an incorrect prediction. We can use the term dark energy for any form of energy that causes the expansion of the universe to accelerate, including a “bare” cosmological constant (see Barnes et al., 2005, for an introduction to dark energy). Cosmological observations constrain the total dark energy. QFT [quantum field theory – VJT] allows us to calculate a number of contributions to the total dark energy from matter fields in the universe. Each of these contributions turns out to be 10^120 times larger than the total. There is no direct theory-vs.-observation contradiction as one is calculating and measuring different things. The fine-tuning problem is that these different independent contributions, including perhaps some that we don’t know about, manage to cancel each other to such an alarming, life-permitting degree. This is not a straightforward case of Popperian falsification. (pp. 34-35)
3) Stenger doesn’t consider the full range of values when deciding if something is fine-tuned or not:
Protons, Neutrons, Electrons
We turn now to the relative masses of the three most important particles in our universe: the proton, neutron and electron, from which atoms are made. Consider first the ratio of the electron to the proton mass, … of which Stenger says: “…we can argue that the electron mass is going to be much smaller than the proton mass in any universe even remotely like ours.” [FOFT p. 164] (p. 50)
The fact that Stenger is comparing the electron mass in our universe with the electron mass in universes “like ours” is all the evidence one needs to conclude that Stenger doesn’t understand fine-tuning. The fact that universes like ours turn out to be rather similar to our universe isn’t particularly enlightening. (p. 50)
Finally, and most importantly, note carefully Stenger’s conclusion. He states that no fine-tuning is needed for the neutron-proton mass difference in our universe to be approximately equal to the up quark-down quark mass difference in our universe. Stenger has compared our universe with our universe and found no evidence of fine-tuning. There is no discussion of the life-permitting range, no discussion of the possible range of [mass(neutron) – mass(proton)] (or its relation to the possible range of [mass(down quark) – mass(up quark)], and thus no relevance to fine-tuning whatsoever. (p. 51)
Those are just a few of the examples in the paper, highlighted in the Uncommon Descent article (emphasis theirs).
By the way, here is a good debate between William Lane Craig and Victor Stenger from 2010 (this is their re-match):
It’s very important, I think, for theists and atheists alike to understand the force of the fine-tuning argument, and how firmly rooted the fine-tuning argument is in science. Christian theists look to science to ground the way we see the world. And this is really just an extension of Paul’s admonition in 1 Corinthians to Christians to be ready to dump Christianity if the resurrection didn’t happen. If the world isn’t the way we say it is, then there is no point in going through the motions to make parents and church people happy.
UPDATE: Peter Sean Bradley note that Krauss is now walking back his rhetoric in response to criticisms from people like atheist John Horgan.
WINTERY KNIGHT 