The True Father Christmas

with Dr Adam Rutherford off of BBC Radio 4’s Inside Science

ASK ANYONE in the street to describe Father Christmas, and they’ll say he’s a ruddy-faced man with a scarlet tunic and a big white beard. However, the REAL Father Christmas could not have been more different from Santa Claus, and he lived thousands of miles from the North Pole. Shy, unassuming, and slight of build, the world’s greatest scientist Sir Isaac Newton was born near Grantham, Lincolnshire, on December 25th 1642. It is entirely thanks to him and his invention of Gravity that we enjoy the festive season we know and love today. Andifyouthink that’sanover-exaggeration of Isaac Newton’s importance to the festive season, then let us imagine what a typical family Christmas would be like if the force of Gravity had never existed.

Every Christmas Eve, excited children leave a mince pie and a glass of sherry for Santa, and a carrot for his magic reindeer

( Rangifer tarandus). But if Newton had never come up with his

gravitational equation F=GMm/r2, these Yuletide offerings for St Nick wouldn’t stay on their occasional table by the fire. They would simply bob around in mid-air, just like they would in a space capsule floating through the gravity-free vacuum of space. Even worse, the occasional table would be bobbing round as well, floating annoyingly in front of the telly.

Decorating your tree in the run-up to a gravity-free Christmas would be infinitely more difficult. The baubles we are familiar with in our post-Newtonian world are pulled towards the centre of our planet by a powerful force that is proportional to the product of their own and the planet’s enormous mass. Without gravity to hold them in place on the branch, they would instead be pushed upwards with an equal and opposite force, shattering on the ceiling and showering everyone with shards of broken glass.

Without Gravity, we would have no point of reference to tell us which way was up or down, so it would be impossible to leave presents “under” the tree on Christmas Eve. Likewise, the tree itself would not have a “top” on which to put the fairy. In an absence of geotropism – the phenomenon that makes roots grow downwards and stems grow upwards – our Christmas trees ( Picea abies) would evolve into bizarre, hovering spheroids, with branches radiating from a central apical growing node, and an infinite number of tops where the fairy could be stuck. On the plus side, there would be no needle drop; although your tree would still shed its needles, they would simply remain floating in mid-air instead of falling on the floor and going in your socks.

But it wouldn’t all be bad news. Believe it or not, if Isaac Newton had never invented gravity, your Christmas dinner would be bigger than ever… and cheaper. Despite the best efforts

of present-day poultry farmers, who pump their livestock full of steroids and exogenous pulsatile growth hormones to plump them up in readiness for the festive season, the size to which a traditional turkey ( Meleagris gallopavo) can grow is limited by the strength of its legs. Freed from the constraints of gravity, these birds could be made to reach truly colossal proportions, meaning there would be plenty of meat left over for sandwiches and curries well into the new year and beyond.

Also, because they wouldn’t be restricted to living on the floor, gravity-free turkeys could be crammed into their rearing sheds in three dimensions. A typical 10 yard x 10 yard coup that accommodates 2,000 free-range turkeys at the moment could easily accommodate 20,000 or more in the absence of gravity. This would push production costs down, and turkeys would become much cheaper in the shops.

Oneof Britain’s best-lovedChristmastraditions is the Queen’s Speech on the afternoon of December 25th, but this could be another tragic casualty of a gravity-free world. After all, if her majesty were to float off into space and suffocate due to a lack of Oxygen (O2 – a colourless and odourless diatomic gas in the Chalcogen group of the Periodic Table that is essential for her majesty’s survival) while making her annual address to the people of the Commonwealth, it would cause a constitutional crisis.

Accordingly, some means of holding the Queen down for the duration of her speech would have to be employed. She could be tethered by monafilament carbon fibre guyropes that would be invisible on screen. Perhaps she could wear lead deep-sea divers’ boots, or she may simply elect to jam her knees under her desk and grip the sides of her desktop tightly.

There is no more welcome sound at Christmas than a band of merry carol singers on the doorstep. Old favourites such as God Rest Ye Merry Gentlemen,

Silent Night and Hark the Herald Angels Sing are all guaranteed to instil a warm, festive glow in a householder’s heart. However, hiding behind the settee until they stop ringing the bell and go away would be much more difficult without Gravity. Either you or your sofa could drift upwards off the ground at any moment, revealing that you were in to any wassailer peeking in through the front window.

Also, carol singers would sound very different. At the moment, we rely upon the force of gravity to hold the earth’s atmosphere firmly in place, providing us with air to breathe at a pressure of approximately 101,325Pa (1.01325 Bar). In its absence, much of our breathable air would simply disappear into the trackless void of outer space, leaving our atmosphere painfully thin. As a consequence, the carol singers’ voices would be much higher pitched, making them sound like Pinky and Perky or Joe Pasquale.

Since it relies on chemically based visco-elasticity rather than gravitational attraction for its adhesive properties, the Sellotape used for wrapping presents would be one of the few things to remain relatively unchanged in a gravity-free Christmas. In fact, one would be hard-pressed to tell the difference between a gift that had been wrapped in the world as we know it from one wrapped in a world where Sir Isaac Newton had never existed. However, if you picked up the present and shook it to guess what was inside, the difference would immediately become apparent. Whilst we, in our Gravity-filled world, can instantaneously tell whether a package contains something heavy, such as a coffee machine or a big socket set, or something light like some fucking socks or fucking hankies, in the absence of Gravity both presents would have exactly the same weight… zero lbs (0.000kgms- in SI units).

No Christmas is complete without a visit to church for the Midnight Service on Christmas Eve. It’s a delightful event that brings the whole community together, only spoiled when the vicar asks for donation to pay for repairs to his leaky vestry roof. But without Isaac Newton’s universal force attracting the rain earthwards from the

clouds with an acceleration of approximately 9.81ms- 2, there would be no need for him ever to get his leadwork fixed. However, it’s unlikely this would stop him handing round the plate, although it would have to be fitted with a powerful electromagnet to stop the coins floating off and getting lost in the rafters.

Perhaps the most satisfying part of Yuletide is the hour each of us spends on the toilet enjoying our Boxing Day stool while perusing a new book. But this pleasurable annual episode in the smallest room is only as relaxing as it is thanks to Newton’s 1686 discovery that every point mass attracts every other point mass by a force acting along a line intersecting both points. For it is Sir Isaac Newton’s Gravitational Constant (6.674×10- 11 Nkg- 2m2) that does the hard work of pulling the dense, figgy-pudding-rich foulage out of our anal sphincters and down into the toilet. If this figure were to be reduced to zero, as it would be had Newton not come up with it, our turds would float upwards and ricochet endlessly from pan to cheek to taint, soiling everything in their path.

Rather than being one of Christmas highlights, our December 26th lavatory visit would be an unhygienic, semi-farcical nightmare. To alleviate this problem, every home would have to be fitted with an aeroplane-style, vacuum-operated toilet that would use negative air pressure to do Gravity’s job.