How we see is an intriguing question - especially for quantum physics. Photo: Mark Mainz/Getty Images
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What does it mean to see something? Take a look at Schrödinger’s cat

It takes only a few photons to trigger our visual sense. Tantalisingly, a few photons can exist in superposition.

What does it mean to see something? It’s a surprisingly philosophical question, especially where quantum physics is concerned.

Quantum physics describes the world at the level of single atoms and smaller, looking at things such as photons, particles of light. These objects are able to be in two places at once, or to spin clockwise and anticlockwise at the same time, a phenomenon known as superposition. Something happens to stop bigger stuff being in two places at once, even though it is composed of atoms and molecules that can exhibit superposition. In experiments, we have achieved superpositions of molecules composed of about 800 atoms but these collapse very quickly. Something about increasing size (or weight) seems to stop the weirdness in its tracks.

Intriguingly, our eyes may help to unravel this. At a meeting of the American Physical Society in Columbus, Ohio, researchers reported that our eyes can register things at the level where quantum weirdness remains. It takes only a few photons to trigger our visual sense. Tantalisingly, a few photons can exist in superposition. The next step is to see whether we notice anything weird when photons in superposition enter our eyes.

This is ambitious. Our unconscious perception is important even to establish whether we see a few photons. The experiments reported in Ohio put subjects in a blacked-out room. When photons were flashed at their eyes, they had to say whether the flash came from their left or their right. Because of the low light intensity, few of the flashes were registered consciously: the subjects couldn’t remember seeing the flash but had to report their gut instinct. They got it right enough of the time to suggest that their brains had registered the photons.

Conscious perception has long been of interest to those who study quantum physics because observation can disturb quantum weirdness. Fire a photon at a double aperture and it will go into a superposition and pass through both apertures simultaneously – but only if no one is looking. Put a detector on the apparatus and the superposition disappears. This is the source of Erwin Schrödinger’s well-known thought experiment. He conceived a situation in which quantum physics leaves a cat both dead and alive, as long as no one observes it.

What is particularly interesting about real-world experiments is that the detector’s presence seems to determine whether the photon behaves like a wave or a particle. It does not require that a person consciously register the result. There is a mystery here about the nature of observation and measurement and what effect it has on the way the microscopic world manifests in our experiments.

No one understands how an atom or photon “knows” that it is – or might be – being tracked. That is what makes the new proposal so exciting. If you cut out the detection apparatus and go straight to the human eye, a slew of questions and opportunities arises. Does a future collision with the molecular apparatus of the retina count as a detection? Is there a difference between human and electronic photon detection? Does it make a difference whether we are conscious or unconscious of the photon’s arrival?

We may have to wait a couple of years for answers. These experiments are beyond our present capabilities, but our horizons are expanding. They promise insight into issues that have been bothering quantum philosophers for a century.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 19 June 2015 issue of the New Statesman, Mini Mao

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The Sad Part Was: this story collection puts the real Bangkok on display

Thai author Prabda Yoon descends into the voices and minds of a small cast of characters.

In Bangkok’s budding literary scene, Prabda Yoon sits at the centre. Born in 1973, he’s the scion of a well-known family (his father Suthichai Sae-Yoon is the co-founder of the Nation newspaper) and is known in Thailand as not only an enfant terrible of letters but as an illustrator, screen-writer and director (his first film, Motel Mist, was shown at European festivals in 2016).

His reputation rests mainly on a collection of short stories published in 2000 entitled in Thai Kwam Na Ja Pen, roughly translated as Probability, and it is from this early collection that most of the stories now collected in The Sad Part Was are derived. Translated with cool elegance by Mui Poopoksakul, they are among the first modern Thai stories to be published in the UK.

As Poopoksakul points out in her afterword, she and Yoon are the products of similar backgrounds and epochs: upper-middle class children of Bangkok who came to consciousness in the late Eighties and Nineties. Often foreign-educated, fluent in English and conversant in global pop culture and media – Yoon did a stint at Parsons in New York after prep school at the Cambridge School of Weston – this new generation of Thai writers and artists were born into a society changing so fast that they had to virtually invent a new language to transcribe it.

In The Sad Part Was, the result is stories that one could glibly label as “post-modern” but which, in reality, perfectly match the qualities of the megacity where they are set. Bangkok is infamously mired in lurid contradiction, but it’s also a city of subtle and distorted moods that journalism and film have hitherto mostly failed to capture. The whimsical and playful surfaces of these stories have to be read against the high-octane anxieties and surreal dislocations of what was, until recently, one of the fastest-growing cities in the world.

Yoon uses the short form of the ten-page story to descend into the voices and minds of a small cast of characters: a schoolgirl and a beautiful female teacher who form a platonic lesbian infatuation while riding a daily bus in “Miss Space”; a couple making love during a thunderstorm whose activities are interrupted by the dismantling of two giant letters, which fall onto their roof in “Something in the Air”; a young man who meets a mysterious older man in Lumpini Park called Ei Ploang, who forces him to consider the intertwined nature of good and evil. In “Snow for Mother”, a mother waits for her little boy to grow up so that she can take him to Alaska to experience the real snow, which he never knew as a little boy in the tropics.

In “The Sharp Sleeper”, a man named Natee obsesses over losing his shirt buttons and is led into a strange reverie on the nature of dreams and the competing qualities of red and yellow pyjama shirts (Thailand’s political culture is riven by two parties popularly known as Red and Yellow Shirts). The commentary slips into effortless sarcasm:

Natee has proudly worn the red pyjama shirt several times since then, and his dream personality hasn’t altered at all. On the contrary, the shirt has encouraged him to become a man of conviction in his waking life. As to what those convictions were supposed to be, Natee wasn’t quite sure. But it was safe to say that a night shirt so principled wouldn’t drop a button so easily.

Since these stories were written, Bangkok’s political schizophrenia has lost its former air of apathy and innocence, but Yoon’s tone is quietly prescient about the eruption of violent irrationality a few years later. It’s a reminder how precious the subtlety of fiction is when set against the shrill certitudes of activism and reportage.

My favorite story here is “Something in the Air”. Its dialogues are written with hilariously archaic, bureaucratic formality, while delving into the disorientation of sexual and romantic hopes in the present century. After the couple’s love-making is interrupted, the young man suggests insolently to the woman that they resume in the open air, exposed to the furious elements. She agrees. They then notice that a dead body is lying on the roof nearby, crushed by the giant letters.

While waiting for the police to arrive, the woman sits quietly and describes her future, a happily married future in which her current lover will play no part whatsoever. He listens in melancholy astonishment until the couple are called to give their testimonies about the dead man. The officers then suspect that the couple themselves have done something scandalous – and so, stung by shame, the woman considers breaking off the relationship and setting in motion her own prophesy.

The Sad Part Was is unique in the contemporary literature of Bangkok – it doesn’t feature bar girls, white men, gangsters or scenes redolent of The Hangover Part II. Instead it reveals, sotto voce, the Thai voices that are swept up in their own city’s wild confusion and energy, and it does so obliquely, by a technique of partial revelation always susceptible to tenderness.

Lawrence Osborne is a British novelist living in Bangkok. His next book, “Beautiful Animals”, will be published by Hogarth in August

The Sad Part Was
Prabda Yoon
Tilted Axis Press, 192pp, £8.99

This article first appeared in the 20 July 2017 issue of the New Statesman, The new world disorder