Quantum Physics And The Snake Of Emptiness

I love getting my melon twisted. I’m betting you do too. I mean, you’re hanging around looking at this blog, so there must be something wrong with you.

My go-to melon-twister is Carlo Rovelli. He’s an academic physicist who specialises in quantum theory. He’s also written some brain-popping popular books about it. I’ve already enthused about them a couple of times.

One of the things that’s fun about Rovelli is that he’s shamelessly partisan. In his latest book, Helgoland, he provides a pop-science explanation of his own pet theory: the “relational” interpretation of quantum mechanics.

He’s completely upfront about the fact that the relational interpretation is the topic of a lively and ongoing debate. He doesn’t pretend that everyone in the field agrees with him. I’m far too ignorant to be able to weigh up the pros and cons. For all I know, Rovelli might be completely off-beam. But the ideas in Helgoland are so dazzling, and he writes about them so elegantly, that it’s impossible not to get caught in the thrill of them.

Unlike my review of Reality Is Not What It Seems, I’m not going to attempt to summarise Helgoland‘s overall argument step by step here. But the thesis in a nutshell is this: the universe is made up not of matter or objects, but of relations and interactions.

In Rovelli’s words:

The best description of reality that we [theoretical physicists] have found is in terms of events that weave a web of interactions. “Entities” are nothing other than ephemeral nodes in this web. Their properties are not determined until the moment of these interactions; they exist only in relation to something else. Everything is what it is only with respect to something else. (p. 166)

Helgoland explains how (some) quantum physicists have reached this conclusion, and what (some of) its implications are. In the process, the book canters entertainingly through the history of science, and also through philosophy – ancient and modern, Eastern and Western.

In particular, Rovelli devotes almost a whole chapter to the ancient Buddhist philosopher Nāgārjuna. That was when I got most excited of all. Excited, but also a bit uneasy.

A Slippery Thinker

Speaking as a proud member of the snake-haired minority (see photo), I love Nāgārjuna.

According to some traditional stories, Nāgārjuna retrieved a Buddhist sutra from the bottom of the sea, where the Buddha had placed it under the protection of the nāgās – supernatural beings that are part-human and part-snake. Iconography often shows Nāgārjuna in conversation with and/or protected by nāgās.

On a less poetic and possibly more factually accurate level, Nāgārjuna was a leading figure in the establishment of Mahayana Buddhism. He was a scholar and a monk, and he probably lived in South India during the second century CE.

The most revered of Nāgārjuna’s works is the Mūlamadhyamakakārikā or “Fundamentals Of The Middle Way”, the central concept of which is Emptiness. It is to this work, and this concept, that Rovelli devotes his chapter in Helgoland.

Rovelli is interested in Nāgārjuna’s concept of Emptiness because it can be used as a tool. The relational interpretation of quantum theory has such wildly radical implications that we need new conceptual tools to think about the world.

The point is not that Nāgārjuna meditated so hard that he magically intuited quantum theory 2000 years early. He didn’t. It’s just that Nāgārjuna came up with a set of ideas that happen to be useful now. Rovelli and his colleagues can use Nāgārjuna’s idea of Emptiness for their own purposes.

Rovelli explains this a billion times better than I can, so I’ll let him take over:

The central thesis of Nāgārjuna’s book [i.e. Mūlamadhyamakakārikā] is simply that there is nothing that exists in itself, independently from something else. The resonance with quantum mechanics is immediate. […]

The technical term used by Nāgārjuna to describe the absence of independent existence is “emptiness” (śūnyatā): things are “empty” in the sense of having no autonomous existence. They exist thanks to, as a function of, with respect to, in the perspective of, something else.

If I look at a cloudy sky – to take a simplistic example – I can see a castle and a dragon. Does a castle and does a dragon really exist, up there in the sky? Obviously not: the dragon and the castle emerge from the encounter between the shape of the clouds and the sensations and thoughts in my head; in themselves they are empty entities, they do not exist. So far, so easy. But Nāgārjuna also suggests that the clouds, the sky, sensations, thoughts, and my own head are equally things that arise from the encounter with other things: they are empty entities. (pp. 126–7)

When you see the world in this relational-quantum way, ordinary things like chairs, tables, clouds and heads become difficult to talk about. One of Rovelli’s explicit ambitions in Helgoland is to infuse contemporary culture with what he calls the “distilled honey, sweet and intoxicating” (p. 165) of relational quantum theory. He wants people other than physicists and philosophers to be able to take relationality on board. Nāgārjuna offers a route into that.

Lovebites And Snakebites

The meaning of Emptiness or Śūnyatā in Mahayana Buddhism is central. It is vast and profound. Whole lifetimes can be spent pondering it.

Consider the celebrated words of the Heart Sutra, for example. One of Mahayana literature’s greatest masterpieces, it dates from around 500 years after Nāgārjuna. It evokes Emptiness with the deceptive simplicity of a crystal:

[…] Here then,
Form is no other than emptiness,
Emptiness no other than form.
Form is only emptiness,
Emptiness only form.

Feeling, thought, and choice,
Consciousness itself,
Are the same as this.

All things are by nature void
They are not born or destroyed
Nor are they stained or pure
Nor do they wax or wane

So, in emptiness, no form,
No feeling, thought, or choice,
Nor is there consciousness.
No eye, ear, nose, tongue, body, mind;
No colour, sound, smell, taste, touch,
Or what the mind takes hold of,
Nor even act of sensing.

No ignorance or end of it,
Nor all that comes of ignorance;
No withering, no death,
No end of them.

Nor is there pain, or cause of pain,
Or cease in pain, or noble path
To lead from pain;
Not even wisdom to attain!
Attainment too is emptiness.

So know that the Bodhisattva
Holding to nothing whatever,
But dwelling in Prajna wisdom,
Is freed of delusive hindrance,
Rid of the fear bred by it,
And reaches clearest Nirvana […]

As these beautiful and mysterious words make clear, the meaning of Emptiness is not merely descriptive, or theoretical, or conceptual. Buddhism is not just a philosophical world view (although it is that too). It is above all a path of spiritual transformation. And the apprehension of Emptiness requires such a transformation.

It’s not that Rovelli gets the concept of Emptiness wrong. His use of it as a tool certainly works. But it’s curiously stunted. Like glimpsing an ocean and thinking: Wow, I could use that to wash my socks.

I confess I’m not clear whether Rovelli gets this or not. On one hand, he explicitly says he’s not at all interested in what Nāgārjuna actually thought or was trying to say two thousand years ago. On the other hand, he also says – on the very same page (p. 131, for those of you following along at home) – that he sees Nāgārjuna as offering a path out of suffering and towards serenity. Which sounds a lot more like spirituality than physics.

Now, I’m not claiming to understand Emptiness either. As Nāgārjuna famously said: “Emptiness wrongly grasped is like picking up a poisonous snake by the wrong end.” It’s beautiful, it’s mysterious, it’s profound, it’s dangerous. In Buddhist terms, understanding Emptiness is not just a life’s work, but the work of many, many lifetimes.

Its apparent overlap with the relational interpretation of quantum theory is exciting and provocative. Quantum is not the whole story of Emptiness, or even a fraction of a fraction of the story. But this side of Enlightenment, a fraction of a fraction may be as much as we can glimpse.

I’m intrigued to know more about Rovelli’s take on Nāgārjuna. So I’m going to tune into his upcoming conversation with the Vajrayana Buddhist Gehse Namdak, which is going to be on that very topic. If you want to check it out too, you can book a ticket online. See you there?

Image credits:
Helgoland book cover reproduced under fair use.
Other images in the public domain.

Take a peek behind the veil.