I love Star Wars, and every time I watch the movies or TV shows, I always wonder whether lightsabers could exist. They seem like the coolest fictional weapons ever imagined. Just think about it: it's a plasma blade contained by pure energy fields. I've always wanted to have lightsabers with my friends—but one mistake could lead to a missing limb… but hey, it's a lightsaber. So what's the physics behind it, and could we one day live in a world where lightsabers become reality?
One popular theory for how a lightsaber could theoretically be possible is through the use of plasma. Plasma is made up of ionized gas, meaning there are free-flowing electrons within it. So, in a lightsaber, you could use a magnetic field to shape and form the plasma into a lightsaber shape, since the free-flowing electrons would respond to it. This would, in theory, give you a real-looking lightsaber, yet there are still many limitations. The first one, ironically, is the magnetic field. To shape the plasma into a lightsaber, you would need to generate a magnetic field that is so unimaginably powerful that we cannot create it with our current technology. Plasma wants to move around; it doesn't want to be contained, making it unimaginably difficult to keep it in place.
The second issue is heat. The heat plasma gives off would not only burn the hand of the user but also burn their entire body, along with any other living thing in its vicinity. At that point, a lightsaber would be more useful from a distance rather than as a futuristic sword. Below, you can see just a little bit of plasma contained within a glass tube.
The most exciting attribute of a lightsaber is the thrilling duels. The sound when lightsabers crash together vibrates through your body, making every fight feel powerful and real. Yet, if we were to use plasma, duels wouldn't be possible. The plasma from the two sabers would simply pass through each other. There wouldn't be any blade-to-blade contact, which would effectively render the entire concept of a real-life lightsaber meaningless. Of course, being able to wave a lightsaber around by yourself is still exhilarating, but without the duels, it loses the very thing that made lightsabers iconic in the first place.
The main workaround would be to use a highly dense plasma that covers a material in the middle of the blade, yet this is still impossible with our modern technology.
However, the single greatest limitation is energy. According to calculations based on lightsabers in the movies, you would need 20 megawatts of power for a single blade. That's enough to power 14,000 homes. Of course, breakthroughs in energy storage and generation are happening rapidly, but if we ever find a way to harness 20 megawatts of power, it surely won't be used for a toy lightsaber. But hey… anything can happen.
While we wait for lightsabers to be available at Target, we'll just have to stay curious and one with the force.