Welcome to the ekpyrotic universe

No money back, no guarantee.

Spurred on by their success with the Higgs boson, physicists have been studying the small print of the universe and it has given them quite a shock. It turns out that there’s a limited warranty: the cosmos may well vanish from existence at some unspecified point in the future. The only crumb of comfort is that, if it does, there’ll be another one along in a minute.

There is good reason to believe that the universe is a stretched rubber band, ready to ping back at a moment’s notice. More stable universes than ours, more akin to a rubber band sitting peacefully on a table, are possible. And the Higgs boson is at the heart of what turns one into the other.

The Higgs boson arises from a field – the Higgs field – that permeates space and time. You can think of it as elastic that runs through the Lycra of the universe. If it provides too much tension, space and time collapse in on themselves, causing the universe to scrunch up and disappear.

The elastic tension is related to the mass of the Higgs boson: the heavier the boson, the safer we are. However, the boson discovered at the Large Hadron Collider at Cern near Geneva is not quite heavy enough: it’s only 98 per cent of the mass needed to safeguard the universe. That seemingly esoteric discovery made in Switzerland last year has serious historical implications, as it turns out. There may well have been a universe before ours and there’ll probably be one after it.

The standard cosmological story deals with only one universe, in which both time and space began at the Big Bang. Here, our best guess for the origin is that something (its other workings are known to us through quantum theory) created a bubble of energy from nothing. Eventually, this energy blew up to become time, space and matter.

Yet there is another possibility. The instability-inducing Higgs mass is a shot in the arm for a theory that has long been in the shadow of the standard Big Bang model of the universe. Proponents of the “ekpyrotic universe” theory (the word comes from the Greek for “born out of fire”) argue that there has been a succession of bangs and scrunches; the cataclysmic death of every universe brings forth a new one.

It’s not a vague, fanciful notion – it comes from the mathematics of string theory, in which the fundamental constituents of the universe are the result of packets of energy that pulsate in ten-dimensional space (OK, so it’s a bit fanciful). The theory suggests that something like our threedimensional universe can be created when two vast and multidimensional objects collide. The collision simultaneously destroys one universe and creates another.

The ekpyrotic universe model has been around for a while and remains widely unaccepted but there is much to recommend it. To make the standard Big Bang story fit with what we see in the cosmos, we have to introduce a few oddities. One is that the universe is peppered with dark matter, exotic stuff unlike anything else we know. There is also an unexplained source of dark energy: a mysterious force that is causing the expansion of the universe to speed up. Then there’s inflation, a force that made the universe 1060 times bigger in the tiny fraction of a millisecond just after the Big Bang.

However, the ekpyrotic universe doesn’t need a period of inflation and, unlike the standard Big Bang model, it can account for where the dark energy comes from. Now, it has support from the Higgs boson. So, enjoy your 21st-century, ecofriendly, self-recycling universe. Just don’t expect it to last.

A picture with a zoom effect show a grafic traces of proton-proton collisions events. Photograph: Getty Images

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 11 March 2013 issue of the New Statesman, The audacity of popes

Getty
Show Hide image

Not just a one-quack mind: ducks are capable of abstract thought

Newborn ducklings can differentiate between objects that are the same and objects that are different, causing scientists to rethink the place of abstract thinking.

There’s a particular loftiness to abstract thought. British philosopher and leading Enlightenment thinker John Locke asserted that “brutes abstract not” – by which he meant anything which doesn’t fall under the supreme-all-mighty-greater-than-everything category of Homo sapiens was most probably unequipped to deal with the headiness and complexities of abstract thinking.

Intelligence parameters tail-ended by “bird-brained” or “Einstein” tend to place the ability to think in abstract ways at the Einstein end of the spectrum. However, in light of some recent research coming out of the University of Oxford, it seems that the cognitive abilities of our feathery counterparts have been underestimated.

In a study published in Science, led by Alex Kacelnik – a professor of behavioural psychology – a group of ducklings demonstrated the ability to think abstractly within hours of being hatched, distinguishing the concepts of “same” and “different” with success.

Young ducklings generally become accustomed to their mother’s features via a process called imprinting – a learning mechanism that helps them identify the individual traits of their mothers. Kacelnik said: “Adult female ducks look very similar to each other, so recognising one’s mother is very difficult. Ducklings see their mothers from different angles, distances, light conditions, etc, so their brains use every possible source of information to avoid errors, and abstracting some properties helps in this job.”

It’s this hypothesised abstracting of some properties that led Kacelnik to believe that there must be more going on with the ducklings beyond their imprinting of sensory inputs such as shapes, colours or sounds.

The ability to differentiate the same from the different has previously been used as means to reveal the brain’s capacity to deal with abstract properties, and has been shown in other birds and mammals, such as parrots, pigeons, bees and monkeys. For the most part, these animals were trained, given guidance on how to determine sameness and differences between objects.

What makes Kacelnik’s ducklings special then, as the research showed, was that they were given no training at all in learning the relations between objects which are the same and object which are different.

“Other animals can be trained to respond to abstract relations such as same or different, but not after a single exposure and without reinforcement,” said Kacelnik.

Along with his fellow researcher Antone Martinho III, Kacelnik hatched and domesticated mallard ducklings and then threw them straight into an experiment. The ducklings were presented pairs of objects – either identical or different in shape or colour – to see whether they could find links and relations between the pairs.

The initial pairs they were presented served as the imprinting ones; it would be the characteristics of these pairs which the ducklings would first learn. The initial pairs involved red cones and red cylinders which the ducklings were left to observe and assimilate into their minds for 25 minutes. They were then exposed to a range of different pairs of objects: red pyramid and red pyramid, red cylinder and red cube.

What Kacelnik and his research partner found was that the ducklings weren’t imprinting the individual features of the objects but the relations between them; it’s why of the 76 ducklings that were experimented with, 68 per cent tended to move towards the new pairs which were identical to the very first pairs they were exposed to.

Put simply, if they initially imprinted an identical pair of objects, they were more likely to favour a second pair of identical objects, but if they initially imprinted a pair of objects that were different, they would favour a second pair of differing objects similar to the first.

The results from the experiment seem to highlight a misunderstanding of the advanced nature of this type of conceptual thought process. As science journalist Ed Yong suggests, there could be, “different levels of abstract concepts, from simple ones that young birds can quickly learn after limited experience, to complex ones that adult birds can cope with”.

Though the research doesn’t in any way assume or point towards intelligence in ducklings to rival that of humans, it seems that the growth in scientific literature on the topic continues to refute the notions that human being as somehow superior. Kacelnik told me: “The last few decades of comparative cognition research have destroyed many claims about human uniqueness and this trend is likely to continue.”