Can Scientists Prove That the Universe Cannot Be Eternal?

In the field of science, the debate over whether the Universe had a beginning remains ongoing. One particular scientist has provided compelling evidence to demonstrate that theories which argue against this idea are fundamentally flawed and lack a solid foundation.

Since its inception, the Big Bang theory has been criticised by scientists who support the concept of an eternal Universe. They argue that the theory closely mirrors the biblical account of creation in the Book of Genesis. If the Universe did indeed have a beginning, as is the current scientific consensus, there must have been a cause for its existence. In this regard, science could propose both natural and supernatural explanations, should it choose to do so.

Unfortunately, naturalism remains deeply ingrained in the scientific community. Many scientists reject the idea of an Intelligent Designer who created the Universe. At the same time, they recognise the need to determine the causes of the cosmos’s origin. Over time, several new and competing theories have emerged, attempting to reconcile the Big Bang theory with the hypothesis of an eternal Universe. These include the eternal inflation model, the cyclic universe model, and the emergent universe model, also known as the cosmic egg model.

In early 2012, Alexander Vilenkin, an American cosmologist from Tufts University in Boston, demonstrated that even if any of the theories mentioned above were true, they would still require a beginning for the Universe. As reported by New Scientist, Vilenkin’s presentation at Stephen Hawking’s 70th birthday symposium was one of the two¹ worst birthday presents Hawking could have received.² Why, then, can the Universe not be eternal?

The Eternal Inflation Theory: Is Inflation Truly Eternal?

Professor Vilenkin first examined the eternal inflation model, a modification of the original inflation theory proposed by Alan Guth in 1981. Unlike Guth’s theory, the eternal inflation model, popularised by figures such as Ethan Siegel,³ suggests the existence of a multiverse that is in a state of perpetual, rapid expansion (inflation). Within this multiverse, ‘gaps’ occasionally form where inflation slows, creating ‘bubble universes’ filled with matter and physical laws. One of these bubbles is thought to be our Universe.

As early as 2003, a team of scientists, including Vilenkin and Guth, sought to test how the eternal inflation theory aligns with the Hubble constant. The Hubble constant defines the expansion of the Universe mathematically. However, the calculations did not align with their hypothesis. The team found that the Hubble constant has a lower bound, which prevents inflation from occurring in both temporal directions (past and future). Therefore, inflation could not have existed eternally without a beginning; there is a boundary in the past where inflation ceases. In other words, even ‘eternal’ inflation must have had a starting point.⁴

The Cyclic Universe Theory: Are Cycles Truly Eternal, and If Not, Why?

The second theory that attempts to reconcile the Big Bang with an eternal Universe is the cyclic universe model (or pulsating universe). This theory suggests that the Universe undergoes cycles of a Big Bang, expansion, contraction, and a Big Crunch, only to explode again. The basic version of the cyclic universe model is also known as the Big Bounce. Another version, called conformal cyclic cosmology (CCC), was proposed by Roger Penrose, though it has been heavily criticised for lacking evidence.⁵ Vilenkin referenced the late astronomer Georges Lemaître, who observed that cyclic universes have ‘an irresistible poetic charm, evoking the image of the Phoenix.’⁶

The problem with this theory, as Vilenkin points out, is that with each new Universe, entropy—or disorder—gradually increases. If there had been an infinite number of Big Bang cycles before our Universe, it should now exist in a state of maximum entropy, or complete thermal equilibrium. This would mean a total absence of complex structures in the Universe.⁷ As New Scientist humourously notes, there would be ‘no stars, galaxies, or physicists’—in other words, none of the structures we currently observe.⁸ Since we clearly see order around us, the cycles cannot be infinite, and there must have been an initial cycle.

One proposed solution to this problem is that each subsequent Universe becomes larger than the previous one, thereby reducing the local scale of entropy. However, if each new Universe is larger than the one before it, tracing back into the past would eventually lead to the smallest possible Universe, which must have been the first. Therefore, once again, the cycles cannot continue indefinitely.⁹

The Cosmic Egg Theory – Which Came First: The Egg or the Universe?

The final theory discussed by Vilenkin is less well-known, though it bears some resemblance to the classic hypothesis of the infinitely small point known as the singularity. The cosmic egg theory (or, more formally, the theory of the static or emergent Universe) suggests that, at its inception, the Universe existed in a quantum ‘egg’ state, which eventually ‘cracked.’ From this ‘cracking,’ our expanding Universe was born (or, as some might humourously put it, ‘growing like a chicken’). It is believed that this ‘egg’ existed in a state of complete internal equilibrium until it ‘cracked.’ In other words, before it ‘cracked,’ it existed in a stable state without any beginning.

However, shortly before the symposium, Vilenkin and his student Audrey Mithani published a paper on the emergent Universe theory.¹⁰ They concluded that this ‘cosmic egg’ could not have maintained quantum stability indefinitely. In quantum mechanics, every possible event has a non-zero probability of occurring, meaning there is always a risk of quantum collapse.¹¹ If the ‘egg’ were to have not cracked, it would eventually have collapsed due to this quantum instability. If it were to have ‘cracked’ before collapsing, it would have done so after a specific period. In other words, the ‘cosmic egg’ could not have existed forever.¹²

The Universe Had a Beginning: However, Could It Have Arisen from Nothing?

Vilenkin concluded his presentation with the following words: ‘All the evidence we have says that the Universe had a beginning.’¹³ In this, we can undoubtedly agree with the professor. Unfortunately, Vilenkin points out that the scientific community has developed models that supposedly offer convincing explanations for the Universe emerging from nothing.¹⁴ One such model is the Hartle-Hawking model, which suggests that, before the Big Bang, the time dimension was so small that it effectively behaved as an additional dimension of space.¹⁵ The four-dimensional space, which is capable of expanding into the Universe we know, is said to have arisen as a completely random quantum fluctuation.

However, these models also have their weaknesses. Questions inevitably arise, such as: What is the origin of this quantum ‘nothing’?¹⁶ What about the rational (and comprehensible) laws of physics? Finally, one must ask: How could a quantum state of minimal energy, concentrated within a space smaller than the Planck length¹⁷—also known as zero-point energy—randomly generate the vast amount of energy that not only caused the Universe to expand rapidly via inflation, but also produced approximately 3.28 x 10⁸⁰ elementary particles travelling through the observable Universe,¹⁸ with exponentially more across the entire Universe? These are not just unanswered questions, but questions for which a naturalistic explanation is difficult to find.

Their greatest weakness, however, is that these are purely mathematical models with little practical connection to real physics. In other words, they are simply speculations. Although based on mathematics, they remain empirically unverifiable speculations.¹⁹ This, therefore, represents a form of non-scientific activity, akin to faith in God as the creator of our Universe.

Or Perhaps…

Alternatively, believing in God as an Intelligent Designer might be more rational than trying to identify naturalistic causes for the Universe’s origin or relying on probabilistic-quantum-mathematical explanations to avoid the issue. After all, science is about seeking the causes of existence and the processes occurring in nature. If a scientific endeavour avoids addressing the cause of a particular phenomenon, it is difficult to consider it science.²⁰ In this regard, the hypothesis of intelligent design may be more scientific than mathematical models that evade causality concerning the Universe’s origin.

Footnotes

1. The second was Hawking’s lost bet about naked singularities.
2. Grossman, L., 2012. Why physicists can’t avoid a creation event. New Scientist, 11 January.
3. Siegel, E., 2017. The Multiverse Is Inevitable, And We’re Living In It. Forbes, 12 October.
4. Grossman, L., op. cit.
5. Siegel, E., 2020. No, Roger Penrose, We See No Evidence Of A ‘Universe Before The Big Bang’. Forbes, 8 October.
6. Grossman, L., op. cit. (own translation).
7. Mitchell, J., 2012. What Happened Before the Big Bang? Tufts Now, 29 May.
8. Grossman, L., op. cit.
9. Mitchell, J., op. cit.
10. Mithani, A.V. & Vilenkin, A., 2011. Collapse of simple harmonic universe. Cornell University, 16 December.
11. Mitchell, J., op. cit.
12. Grossman, L., op. cit.
13. Ibid.
14. Mitchell, J., op. cit.
15. Adamczyk, A., 2018. Gdy czas był przestrzenią: Model Hawkinga-Hartle’a. Kwantowo, 11 May.
16. That “nothing” always hides a quantum vacuum state.
17. Planck length is the smallest measurable length: 1.616255(18)×10⁻³⁵ m.
18. Bennett, J., 2017. How Many Particles Are in the Observable Universe? Popular Mechanics, 11 July.
19. Catchpoole, D., 2012. Physicists: The universe had a beginning. Creation Ministries International, 5 July.
20. Sarfati, J.D., 2013. In the beginning God created—or was it a quantum fluctuation? Creation Ministries International, 21 November.
    

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