Jolly Old St. Physicist
25 Dec. 2021

Credit: Getty Images
Look! Up in the sky! It’s a bird! It’s a plane! It’s Santa traveling through a wormhole? When first thinking about delivering billions of gifts to children all around the world in one night, it may seem like Santa would never be able to complete his job with just an open-top sleigh and a team of reindeer. Certain Scrooges among us entertain this idea, insisting that such a feat would be scientifically impossible. But what if Jolly Old St. Nicholas was actually an ingenious physicist? With a dive into general relativity and quantum mechanics, all we need is a little Christmas spirit to start to unwrap the mystery of Santa.
One of the easiest strategies Santa could employ to achieve his task is using wormholes. Wormholes, or tunnels that connect two distant points in space or time, are theoretically possible by Einstein’s theory of general relativity, and they would allow Santa to travel enormous distances in very short amounts of time. Dan Holz, a professor of Physics at the University of Chicago, notes that without traveling through wormholes, Santa would have to travel near the speed of light and that the constant deceleration and acceleration of stopping at and starting from each house would kill a normal human, posing issues for Santa. So, this is why Holz finds, “Santa can keep going through a wormhole, doing what needs to be done at whatever leisurely pace he prefers — and given his belly, it’s easy to imagine that’s the option Santa would take.”
If Santa is unable to find a wormhole which he could travel through, he could have become a master of the multiverse. Quantum mechanics interprets the universe as being made of a countless number of duplicate universes, with the past unchangeable but the future uncertain until we make a decision. Dick Ahlstrom, Science Editor of the Irish Times, explains that Santa “can choose a home and appropriate toys and instantaneously be there to deliver them, with that house and presents fixed in time,” moving on to “the next multiverse home with its mix of toy options.” With this theory, Santa may have found a way to handle and traverse the multitude of universes in order to ensure every child receives their gifts.
Speeding from one house to the next with a whole sleigh of presents, though, would require great amounts of energy and, similarly, fuel. A brilliant explanation for this obstacle arises from one of the most indispensable traditions of Christmas: leaving out cookies and milk. Assuming that Santa delivers around 4.5 pounds of toys to each household, he would have to carry about 4000 times the payload capacity of the largest aircraft. As it turns out, however, rocket fuel is inefficient, as only about 0.001% of its mass is used for powering the spacecraft. As American science writer Ethan Siegel considers, it is theoretically possible for Santa’s reindeer to convert every bit of mass from the cookies and milk into energy according to Einstein’s E=mc2. This, then, would supply his sleigh with enough energy to deliver every toy to all the households in the world.
The application of just these few physics principles can help prove that it truly is possible for Santa to exist. The magical mystery of how he can complete his job in such a short period of time not only makes the holidays more exciting but also serves as a reflection of science taught in schools. Certain concepts are taught to exist and apply to various situations, even though we are not explicitly shown why or how. Sometimes, though, we need to trust the process and have faith that accepting what we learn will make sense as we continue developing our understanding of the sciences and the world. Because, as Holz notes, “it’s nice to have some magic in one’s life.”
