The Physics of Waterbending
The Physics of Avatar: The Last Airbender and The Legend of Korra
Let’s continue our journey into the physics of bending with the element of change, water.
I recommend you read my first post on the physics of Avatar and Korra if you haven’t already. It will be important for understanding this series.
Moving Water
The most basic part of waterbending is just moving water. There are actually two pretty straightforward ways to do this. You see water is diamagnetic, which means in the presence of a magnetic field, water molecules will produce an opposing magnetic field. The end result is that the water is repelled by a magnetic field. So all a waterbender would need to do to move water is create a magnetic field. As we discussed in the last post, benders can likely create electric currents by forcing the motion of charged particles. An electric current traveling in a circuit automatically produces a magnetic field. This field is made stronger when the current travels in a loop called a solenoid. A circuit with a solenoid in it is called an inductor. By generating electric currents in the form of inductors within a thin layer of the water being bent, waterbenders could repel water and make it move anyway they wanted. Here are some visuals to help illustrate this idea:
In addition to being diamagnetic, water molecules are also polar molecules. This means that regions of the water molecules are electrically charged, so an alternate way to move water is to use the positive and negative charges of excitons to attract water molecules. Here is a video demonstrating this effect:
Water is still diamagnetic in its solid state, so waterbenders could just as easily use magnetic fields to move ice and snow. Bloodbending and plantbending should work the same way since both techniques essentially boil down to moving the water inside humans, animals and plants. Waterbenders could also use this ability to move water to heat it up so that ice melts and water evaporates. They’d likely do this by creating pressure waves, a.k.a. sound waves, in the water or ice to increase its thermal energy so that it changes phase. Changing the phase of water in the other direction is going to be more complicated.
Water Propulsion
Water propulsion is pretty simple now that we understand moving water. Rather than create inductors within a layer of the water being bent, the waterbender creates the inductors in themselves so that they are pushed in the opposite direction of the water being repelled by their magnetic field. This water would be collected behind the bender using waterbending. This process would likely involve waterbenders running a large electric current through their body that would be harmful to an ordinary human, but people in the world of Avatar appear to consistently survive conditions that would be fatal to real humans.
Freezing Water and Bending Water Vapor
Freezing water can be explained with the same physics as simply moving water, but it would require far greater precision. To freeze water, the waterbender would need to manipulate the motion of individual water molecules and slow them down to reduce their thermal energy. Every force applied to each water molecule would need to be carefully aimed so as to be directly opposed to whatever random direction that molecule was moving in its natural vibration. It would likely be easiest to do this by using electric fields created by excitons and polarons to effect the polar water molecules. It may not be possible for a waterbender to create electric currents that flow in looped inductors at the scale of individual molecules, but they still could create magnetic fields in other ways at this scale. For example, they could generate magnons like I mentioned in my last post. The same process used in freezing water would also be necessary to bend steam and fog or condense water vapor into a liquid. This is because in gaseous form water molecules are no longer bound together by cohesion. A waterbender moving water vapor would need to bend all the molecules individually. Freezing is a bit easier than that because a waterbender could just continually cool the surface of the water and let heat flow out from below said surface.
Healing with Water
Water healing at first struck me as the place where the shows broke their own rules and gave water properties it didn’t naturally have, but I think I’ve figured out how it works. We’ve already seen that in order to freeze water and bend water vapor waterbenders would need to be able to influence the motion of water down to the molecular level. With this amount of precision, it’s reasonable to conclude water benders could also use water molecules to move around other molecules suspended in water. My theory is that waterbenders are manipulating the flow of water at such small scales that they can flush out pathogens, reassemble bodily tissues and even aid in the metabolic processes within someones body. Since many of the substances waterbenders would need to move around when healing are larger than individual water molecules, they would be able to make use of the inductor method I outlined before more easily then when freezing water or controlling steam. The real question is: why does the water glow? My guess is that the magnetic fields being produced are so tightly wound on the small scales involved in healing, and that the inductors are so close together, the magnetic fields overlap and become strong enough to force electrons moving around in the water to accelerate. We’d already expect there to be electrons in the water moving free from their atoms because bending likely involves excitons. In a magnetic field, charged particles move in circles. If the electrons are forced to move fast enough in their circular paths, they may exceed the speed of light in water(which is slower than the speed of light in a vacuum). Whenever a particle exceeds the speed of light in a medium, it begins to emit Cherenkov radiation. This is what that radiation it looks like:
Look familiar?
If waterbenders can run precisely controlled electric currents through the water they bend, they may also be able to influence the bioelectric signaling in a person’s body. Bioelectricity plays a significant role in the regeneration of tissues, and you can learn more about it here:
Drawing Energy from the Tides
It’s common knowledge in Avatar that waterbenders draw power from the Moon, seeing how the moon is what pulls on the ocean to create tides. One way of interpreting this is that the motion of the water caused by the Moon provides waterbenders with energy. Now in order to bend water, or any element for that matter, benders need to establish a physical interaction between the substance being bent and the electromagnetic fields they produce. This means that not only can the fields transfer energy to the substance, but the substance can transfer energy to the fields. So the natural kinetic energy of water molecules, when moving in the presence of a waterbenders’ magnetic field, could be transferred to said field and increase the energy stored within it. According to Michael Faraday’s law of induction, a changing magnetic field produces an electric current, and electric currents can transfer energy.
If the motion of water molecules in a magnetic field causes it to increase in stored energy, then it would produce an electric current that would carry some of the energy from the motion of those molecules. If waterbenders could then get the current to flow to them from the location of the inductors creating the magnetic fields, using quasiparticles to improve conductivity in the air or whatever the current travels through, then they would be able to draw energy from the motion of water molecules caused by the tidal forces from the Moon. This idea introduces the concept that benders draw energy from far away, meaning they must be using the process of quantum entanglement mentioned in my last post to influence physical systems as large as the planet Earth in small ways. This range of energy collection would be necessary for them to pull off the feats we see in the shows. This explanation even explains why waterbenders are at their strongest during a full moon, because that is the time when the Moon, Sun and Earth are all in alignment. At this time, both the Sun and the Moon are pulling in opposite directions, creating maximum displacement for water on Earth’s surface and maximum tidal forces. Technically, this also occurs during a new moon(when the Moon isn’t visible at all), so waterbenders should also be powered up then. As for why waterbenders are also stronger at night, I think it may be because their style of bending relies heavily on the magnetic part of electromagnetism, and electromagnets work better at colder temperatures because electricity flows more easily through cold materials.
That concludes our analysis of the benders of the Water Tribe.
In my next post, I’ll be looking at the physics of earthbending. I hope to see you there. Also, please let me know anyways I can improve my hypotheses or better explain them.
Works Cited
DiMartino, M. D., & Konietzko, B. (Writers). (2010, June 30). Avatar: The Last Airbender [Television series]. Nickelodeon.
DiMartino, M. D., & Konietzko, B. (Writers). (2012, April 14). The Legend of Korra [Television series]. Nickelodeon.
Patrick, M. (Producer). (2019, September 26). Film Theory: Avatar and the Science of Waterbending (Avatar the Last Airbender) [Video file]. Retrieved August 5, 2020, from https://www.youtube.com/watch?v=e-kU0FPwXSc&list=LL9IjFp5KSeYJpXJvPrSAENg&index=295
Steele, Z. (2020, August 05). The Physics of Avatar: The Last Airbender and The Legend of Korra. Retrieved August 05, 2020, from https://medium.com/whiteboard-to-infinity/the-physics-of-avatar-the-last-airbender-and-the-legend-of-korra-1c212efb4b9a
Nicholson, J. (2019, March 02). How Does a Solenoid Work? Retrieved August 05, 2020, from https://sciencing.com/a-solenoid-work-4567178.html
Plasma Channel (Producer). (2016, August 10). How to WATER BEND | Using ELECTRICITY | PLASMA [Video file]. Retrieved August 5, 2020, from https://www.youtube.com/watch?v=0dS7-I2c1Eg
Grigalunas, R. (2019, July 31). What Is An Inductor? — ES Components: A Franchised Distributor and Manufacturer. Retrieved August 05, 2020, from https://www.escomponents.com/blog/2019/7/31/what-is-an-inductor
Hartley, J. H. (2000, January 25). Is Snow or Ice Magnetic? Retrieved August 05, 2020, from http://madsci.org/posts/archives/2000-01/948845813.Es.r.html
Baird, C. S. (2015, November 5). Can sound waves generate heat? Retrieved August 05, 2020, from https://wtamu.edu/~cbaird/sq/2015/11/05/can-sound-waves-generate-heat/
Ling, S., Sanny, J., Moebs, W., Friedman, G., Druger, S., Kolakowska, A., . . . Janzen, D. (2018, November 28). 8.3 Motion of a Charged Particle in a Magnetic Field. Retrieved August 05, 2020, from https://openpress.usask.ca/physics155/chapter/8-3-motion-of-a-charged-particle-in-a-magnetic-field/
Alaeian, H. (2014, March 15). An Introduction to Cherenkov Radiation. Retrieved August 05, 2020, from http://large.stanford.edu/courses/2014/ph241/alaeian2/
Muller, D. (Producer). (2012, October 9). Levitating Barbecue! Electromagnetic Induction [Video file]. Retrieved August 5, 2020, from https://www.youtube.com/watch?v=txmKr69jGBk
US Department of Commerce, N. (2005, June 01). Tides and Water Levels, Tidal Variations — The Influence of Position and Distance, NOS Education Offering. Retrieved August 05, 2020, from https://oceanservice.noaa.gov/education/tutorial_tides/tides06_variations.html
Heat Resistance. (2019, June 17). Retrieved August 05, 2020, from https://nationalmaglab.org/education/magnet-academy/watch-play/interactive/heat-resistance
Steele, Zia. “Will Humans Ever Regenerate Like Time Lords?” Medium, Whiteboard to Infinity, 31 Aug. 2020, medium.com/whiteboard-to-infinity/will-humans-ever-regenerate-like-time-lords-6dd0d12601b0.
