Vilenkin and Mithani: Did the Universe Have a Beginning?

Frequently when debating with an atheist I will bring up the beginning of the universe as evidence for a creator and the typical response is, “We don’t know that the universe had a beginning.”  Their claim is that models exist that are eternal, so the universe may not have had a beginning.  So far, this claim has not been supported by the math.  Alex Vilenkin and Audrey Mithani wrote a paper called, “Did the universe have a beginning?” where they examine,

“three candidate scenarios which seem to allow the possibility that the universe could have existed forever with no initial singularity: eternal inflation, cyclic evolution, and the emergent universe.”

 

                                          

Here is what they wrote about each type of model:

Eternal Inflation Models

These models theorize that there was a period of exponential inflation during the very early phases of the Big Bang.  These type of models solve several questions surrounding the standard Big Bang model, which makes it a likely candidate for being plausible.  One of the consequences of these models is that they predict a multi-verse.  Once started inflation will continue into the infinite future.  The science magazines love to talk about this prediction as possible evidence for a multi-verse, but there’s a catch; the BGV Theorem has shown that if on average the universe is expanding, the universe/multiverse had a beginning. 

“Therefore, although inflation may be eternal in the future, it cannot be extended indefinitely to the past.”

Cyclic Models

Another type of model examined is the cyclic model.  These are the models that have an infinite series of big bangs followed by big crunches.  Entropy gives these models a couple of problems:

1).  With each bang/crunch cycle, the entropy continues to increase.  If the universe were eternal, we should have run out of usable energy and entered a state of “thermal death”.

2).  One way to avoid the thermal death scenario is to have each subsequent expansion get bigger and bigger for an infinite amount of time.  If this were to happen, the universe would on average be expanding more than it is contracting, which brings you back to the BGV theorem and a beginning.

Emergent Universe Models

In the emergent universe scenario, the universe is in a static quantum state until the “cosmic egg” decides to crack open.  This would bypass the requirement of the BGV theorem such that the average state of the universe would not be one of expansion.  In order for this type of model to succeed, a couple of conditions must be met.

“First, the universe should be stable, so that quantum fluctuations will not push it to expansion or contraction. In addition, it should contain some mechanism to exit the stationary regime and begin inflation.”

Vilenkin and Mithani demonstrate that quantum instability exists because there is a non-zero probability of quantum collapse, so the universe could not have existed in a quantum state for an infinite amount of time.

“Since the tunneling probability is nonzero, the simple harmonic universe cannot last forever…..there do not seem to be any matter sources that admit solutions that are immune to collapse”

Summary

While in scientific terms we are not 100% certain that the universe had a beginning, since nothing in science is considered to be 100% certain, all of the evidence we have suggests that it does.  This paper demonstrates that “eternal” models can only be eternal in one direction; the future. 

“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.”

Roger Penrose on entropy: How did he calculate that?

 

One of the fine-tuning arguments frequently used is the low entropy state of the universe at the Big Bang.  This was calculated by Roger Penrose to be 1:10¹⁰¹²³.  How does he do this?  He explains it in his book, The Emperor’s New Mind.  Here is the section of the book that discusses it.   Penrose uses the Bekenstein-Hawking formula for the entropy of a particle in a black hole to determine the entropy of a particle at the singularity of the Big Bang as if the entire universe were a giant black hole.  He calculates this to be 10⁴³.  There are estimated to be 10⁸⁰ particles in the observable universe. 

 

10⁸⁰ x 10⁴³ = 10¹²³ . 

Entropy is on a logarithmic scale, so that is how he arrives at 10¹⁰¹²³. 

V = total phase-space volume available

W = original phase-space volume

V/W = 10¹⁰¹²³

 

Therefore, the accuracy of the low entropy value was 1:10¹⁰¹²³.  Penrose says,

“This is an extraordinary figure. One could not possibly even write the number down in full, in the ordinary denary notation: it would be `1' followed by 10<sup>123</sup> successive `0 's! Even if we were to write a `0' on each separate proton and on each separate neutron in the entire universe-and we could throw in all the other particles as well for good measure-we should fall far short of writing down the figure needed. The precision needed to set the universe on its course is seen to be in no way inferior to all that extraordinary precision that we have already become accustomed to in the superb dynamical equations (Newton's, Maxwell's, Einstein's) which govern the behaviour of things from moment to moment.”

 

If there are more particles in the universe than 10⁸⁰ (like an infinite number), all the more extraordinary!!

Sean Carroll pointed out in his debate with William Lane Craig that this low entropy value was not a requirement for life to exist and, therefore, should not be considered finely tuned by a creator.  As I discussed here, Robin Collins addresses this in his paper claiming that without a low entropy at the Big Bang, we would not know that our universe had a beginning and some of our fundamental laws of physics would not have been discovered.

The BGV Theorem

 

In 1927, Georges Lemaître (a priest) proposed the greatest cosmological theory of the last century:  The Big Bang Theory.  There have been numerous confirmations that the Big Bang Theory is true, such as the expansion of the universe and the cosmic microwave background radiation.  This theory has caused a lot of heartburn to the scientific community, since it says that the universe had a beginning.  Atheists do not want the universe to have a beginning because this requires an external agent to cause the change in state and they know what the implications are.  Since the Big Bang Theory was first proposed, atheist scientists have desperately tried to disprove that the universe had a beginning, but unfortunately for them, one cannot disprove the creator of science by using the science he created. 

There have been many additional theories that have been proposed that attempt to incorporate the Big Bang Theory and an eternal universe in order to avoid a beginning.  They have all failed.  The nail was once again put into the coffin in 2003 by a theorem developed by Arvind Borde, Alan Guth, and Alexander Vilenkin known as the Borde, Guth, and Vilenkin (BGV) Theorem.  What they discovered is that any universe that is on average expanding cannot have an infinite past; there is a past boundary.  This rules out all models that try to avoid a cosmic beginning.  Here is the link to their paper and here is a video of Vilenkin explaining the theory.  Here is a quote from the paper.

“Our argument shows that null and timelike geodesics are, in general, past-incomplete in inflationary models, whether or not energy conditions hold, provided only that the averaged expansion condition Hav > 0 holds along these past-directed geodesics. This is a stronger conclusion than the one arrived at in previous work in that we have shown under reasonable assumptions that almost all causal geodesics, when extended to the past of an arbitrary point, reach the boundary of the inflating region of spacetime in a finite proper time (finite affine length, in the null case).”

 

What this is saying is that the only condition that needs to be present to show that ANY universe has a finite past boundary (a beginning) is that it must have an average state of expansion.  This applies to our universe or the multi-verse (if you have faith in such a thing).  There is no doubt in the scientific community that our universe is expanding.  This was discovered by Edwin Hubble in 1929 by looking at the red shift of distant galaxies and repeatedly confirmed.  Since then we have discovered that not only is our universe expanding, but the expansion rate is also accelerating. 

 

“It is said that an argument is what convinces reasonable men and a proof is what it takes to convince even an unreasonable man.  With the proof now in place, cosmologists can no longer hide behind the possibility of a past-eternal universe.  There is no escape, they have to face the problem of a cosmic beginning.” – Alexander Vilenkin

Yet atheist scientists still have trouble admitting that the universe had a beginning and have proposed all kinds of nonsensical, non-falsifiable, faith-based theories to show that the beginning of the universe had a natural cause.  By refusing to follow the evidence, they are saying “Anything, but not God”.

“At this moment it seems as though science will never be able to raise the curtain on the mystery of creation. For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountains of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greeted by a band of theologians who have been sitting there for centuries.”  - Robert Jastrow, God and the Astronomers (1978)

 

Genesis 1:1 - In the beginning God created the heavens and the earth. 

 

Good luck to all who try to disprove this.