The multiverse is a religion by any other name

At the end of the 17e century, the German philosopher Gottfried Leibniz said: “The first question that should be asked is: ‘Why is there something rather than nothing?’ » Leibniz turned to this question to prove the existence of God. His reasoning was as follows:

1. Everything that exists has an explanation for its existence.

2. If the Universe has an explanation for its existence, that explanation is God.

3. The Universe exists.

4. Therefore, the explanation for the existence of the Universe is God.

According to this logic, obviously, God exists. But the only obviously correct statement in Leibniz’s reasoning is number 3: the Universe exists. Number 1 is debatable, because “everything” is too strong a quality. Yes, we can explain clouds, atoms, rainbows, and the composition of Jupiter’s atmosphere, using materialistic arguments. But Leibniz pushes this to also include supernatural explanations. He invokes the God of Gaps argument, where gaps in scientific knowledge serve as proof of the existence of God. In this case, since the Universe exists, and since science cannot explain the Universe, only God can explain the Universe. Therefore, God exists.

Slip into cosmic inflation

The very success of the science that emerged during the 17th and 18th centuries – mechanics and Newtonian gravity, optics, chemistry, etc. – created a distance between science and religion. The trend has continued strongly for 300 years, and now most people accept a clear separation between the two. Religion may inspire many scientists, but it is no longer part of scientific discourse.

This was true, at least, until the advent of the multiverse hypothesis in recent cosmology.

The multiverse is a strange idea. Its roots are very old, dating back to ancient Greece. (The interested reader should consult the excellent book by Mary-Jane Rubenstein.) There are two main inspirations for the modern version of the multiverse: inflationary cosmology and superstring theory. In inflation, the Universe undergoes an ultra-rapid exponential expansion very early in its infancy, a few fractions of a second after the Big Bang. The expansion is propelled at such speed by a hypothetical field called the inflaton – essentially a fluid presence that permeates all of space and has the unique property of separating space. A simple image is of a child going down a slide. Why does the child come down? Since it is not on the ground (the lowest point), there is potential gravitational energy which is converted into kinetic energy (movement) when the child slides. When the child hits the ground, all of this potential energy has been converted into kinetic energy. On impact, this energy is converted into friction and heat.

Inflation is similar. It starts with its potential energy, and as it slides down, this is converted into kinetic energy. But since the inflaton fills all the space, this process causes the space to expand like a balloon.

Subscribe to get counterintuitive, surprising and impactful stories delivered to your inbox every Thursday

The multiverse comes into play when we add quantum physics to this picture. In quantum physics, everything is nervous. Inflation is also nervous. This means that as it descends, quantum effects may cause it to rise a little up in some regions of space, or down in others. Since the amount of potential energy determines the speed of expansion of the Universe, inflation will cause regions of space to expand faster or slower. The universe is divided into several universes, each with its own rate of expansion. This collection of Universes, or cosmoids, is the inflationary Multiverse. We live, supposedly, in one of these bubbles.

Arranging the multiverse

In superstring theories, the multiverse originates from the string landscape. In short, superstring theories require additional six-dimensional spaces. This means that superstrings live in nine-dimensional spaces. But we don’t. At some point very early in the history of the Universe (or possibly earlier, it’s not clear), six of these nine dimensions coalesced and remained very small, while the other three – those we live in – have continued to grow. My doctoral thesis, in the mid-1980s, looked at different scenarios that would keep these extra dimensions small so that we couldn’t see them.

Now this additional six-dimensional space has a form, a topology. In fact, it can have many different topologies, and each of them generates a different three-dimensional universe. The theory predicts that the reason why the Universe is the way it is – why the electron has the mass it has, why gravity or electromagnetism have the intensity they have – is due to the shape and topology of this additional six-dimensional space. We can imagine the string landscape as the set of all possible shapes that this extra space can have. Each generates a different three-dimensional universe, with different physical properties. Ours, according to the theory, would be the only one to have physical variables with the values ​​that we measure in the laboratory.

The superstring multiverse is therefore the collection of all these universes that appear in the string landscape. And what does that have to do with God? Well, proponents of the theory argue that our universe is fine-tuned to be what it is and to have the properties it has. These properties include the existence of observers who can theorize about them. Some will say that this fine-tuning requires a finisher, i.e. God. If you don’t want a fine-tuning God, having a plethora of possible universes reduces the problem to a kind of cosmic lottery game. Among many universes, ours is only one. We won the cosmic lottery, at least if you consider our existence a victory – and we didn’t need a God to win it.

Familiar philosophical framework

How reasonable is this argument? First, from a physical point of view, we must accept that superstring theory is a “fundamental theory of ‘everything’, including its predictions of supersymmetry – an additional symmetry of nature which predicts that every particle has a supersymmetric partner – and six extra dimensions of space. So far, we have no experimental evidence for either of these two properties. We have found no supersymmetry and no extra dimensions. argue that supersymmetric particles may simply be too heavy to be seen by our current accelerators, while extra dimensions are too small to detect.Perhaps, but we can never falsify this theory: particles can always be too heavy and the extra dimensions may always be too small to be detected by any machine we build. let’s do.

Ditto for the Multiverse. By construction, these additional Universes exist outside ours and are therefore not directly detectable. They can cause indirect signals, possibly from past collisions, but no such signal has been detected. On a physical level, there isn’t much support for the string landscape and its multiverse.

And philosophically? The whole “if you don’t love God, you better have the multiverse” argument is very similar to Leibniz’s, just backwards. This may be surprising for multiverse enthusiasts to hear. But it should be clear that the Multiverse, in a curious inversion, plays exactly the same role as the God-of-Swerves. The existence of God is not provable by observations. The multiverse is not provable by observations. God explains the Universe. The Multiverse explains the Universe. So the multiverse looks a lot like God. Weird, right?

The false assumption is that something that exists requires an explanation, regardless of the cost of that explanation. In the case of the Universe, it is the problem of the First Cause, the uncaused cause which makes the Universe become. This transition from being (God or a causeless multiverse) to becoming has twisted our logical arguments into knots for at least 3,000 years, and probably longer. So the question is: What is the price to pay for an “answer”? Is the price a supernatural cause or an unverifiable scientific explanation? And in the end, does accepting one or the other make a difference? Does it offer a way out? Rather, we should accept that not all questions need to be answered to make sense.

Comments are closed.