When you want to travel a long distance, from one continent to another, you book a plane flight hoping to spend a few hours in the air. However, when it comes to space travel, you need to travel fast because all points of interest are very far away.
Space explorers have always been looking for a way to travel faster than light, allowing them to travel more quickly in deep space! Basically all the methods discovered have significant drawbacks, we can walk without bumping into objects unexpectedly. However, you’ve probably heard that light travels and travels fast.
But how fast is light? Interestingly, the exact speed of light is known and is the basis for most other measurements. The speed of light in a vacuum is exactly 299,792,458 meters or 983,571,056 feet per second. This means that light will travel approximately 186,282 miles in just one second. The light is so bright that if you turn on a single bulb in a dark room, the light fills in almost instantly.
You may not know that light travels. Another unit of measurement related to light is the light year, which is the distance that light can travel in one year. This value is approximately 6 trillion miles or 10 trillion km. It is one way astronomers and physicists measure extreme distances in our universe. As mentioned earlier, the universe is so vast that it can take many years for light to travel from one part to the other! For example, light travels from the Moon to our eyes in about 1 second, which means the Moon is about one light-second away.
However, it takes about 8 minutes for the Sun’s light to reach our eyes, which means that the Sun is about eight light-minutes away. Light from Alpha Centauri, the closest star system to us, takes about 4.3 years to reach, so Alpha Centauri is 4.3 light years away! Other stars and objects beyond our Solar System are anywhere from a few light-years to a few billion light-years! This is why what astronomers “see” in the distant universe is actually history.
When they study distant objects, they are seeing light that shows objects as they existed at the time the light left them! While there are many fascinating things you can do with light, scientists have tried to find a way to travel at the speed of light. This is interesting because humans will eventually become an interplanetary species. For example, Elon Musk, the billionaire CEO of SpaceX, wants to build a settlement on Mars, but his explorers have to travel through space for at least five months before touching down on the Red Planet.
It can even reach almost a year, depending on how close the two planets are! And that with all the dangers it brings before landing on the Red Planet! However, even with the speed of light travel, they can make a long journey in less than four minutes! Researchers have tried many different methods to travel at very high speeds. However, until a scientist announced a new discovery. It’s also very hard to achieve even one percent of the speed of light, which is still pretty fast since it can get you from Los Angeles to New York in a little over a second, very hard! The problem is, in a word, energy.
Any moving object has energy due to its motion, and physicists call this kinetic energy. To go faster, you need to increase kinetic energy. The problem is that it takes a lot of kinetic energy to accelerate! It takes four times as much energy to make something go twice as fast. Moving something three times as fast requires nine times as much energy, and so on. For example, to get a teenager weighing 110 pounds from 1 percent of the speed of light would cost 200 trillion joules! This is roughly the same amount of energy as the U.S. 2 million people use in a day.
Take the mdrive, for example, which was touted as the technology that would take us to the most distant parts of the universe much faster. The invention, which has also been patented, works in principle by trapping microwaves in a shaped chamber where their bouncing creates thrust. The chamber is closed, meaning from the outside, it will appear to just be moving without any fuel input or any thrust output! The mdrive relies on Newton’s second law, where force is defined as the rate of change of momentum. Thus an electromagnetic, or EM, wave traveling at the speed of light has a certain momentum that will move a reflector, resulting in a small force.
This small force accumulated over a large amount is what enables the EmDrive, which sounds simple, but essentially changes our understanding of physics as well! No energy is going in or out, which leads us to ask the question, how do waves get started, how do they keep going, and where is their momentum coming from? You can’t have spontaneous, built-up momentum without some exploratory push, which is why many scientists don’t take the EmDrive seriously. If the mdrive works, it invalidates everything physicists know about the universe.
The Mdrive was also put to the test by physicists from the Dresden University of Technology, showing promising results obtained by NASA and showing the Chinese assert they were all false positives that were explained away by external forces! However, warp drive shows great promise, as Dr. Portrayed by Eric Lentz. Even Lentz wasn’t the first to work on making warp drive a reality, and not just science-fiction. The first person to attempt this was the Mexican mathematician Miguel Alcubierre.
In 1994, his proposal became the official literature debut on the warp drive. Unfortunately, the “Alcubierre warp drive,” as it has become known, requires a staggering amount of energy, along with terrifying exotic matter as a co-ingredient. This highly radioactive material is only theoretical and not something that researchers have actually observed in nature, much less been created. A handful of variations have since been suggested, including former NASA engineer Dr. Harold G. Contains a 2010 update to the physical design of the Alcubierre Drive, created by “Sonny” White.
His update reduced the amount of energy needed to a less challenging number, even though it was still not practical because the solution still required exotic matter, albeit much less than the Alcubierre solution. Another group of researchers from Switzerland, known as Applied Physics, APL, put forward their concept.
Interestingly, their drive didn’t require any exotic material to create the warp bubble. However, his model could not go beyond the speed of light, which is the holy grail of space travel. To explain how his concept differs from those previously proposed, Lentz first points to the physical structure of the classical Alcubierre drive, on which almost all other solutions are more or less based.
He noted that the Alcubierre solution provided an intuitive picture of what a warp drive would do, i.e. contract the space immediately in front of the central area containing the ship or transport, and expand the space immediately behind. This shows warp drive as a wave of curvature on which a ship will travel to its destination! Even though it is a cornerstone of warp travel, Lentz argues that it is not even an essential feature. Instead, he says, a solution proposed by physicist José Natario in 2002 showed that expansion and contraction were not necessary to propel the ship.
That work inspired him to rethink how a warp could be made using only conventional materials, not exotic materials. Natario was able to prove that the expansion can be trivial or zero everywhere and still do the same job of steering! This is a significant breakthrough as it means that the space-distorting exotic matter in almost all theoretical warp drive solutions is no longer needed in front of the theoretical passenger and behind them.
Building on Notario’s theory, Lentz created his own variation that he believes is even more tenable because it is rooted in conventional physics. In addition to this major physical difference, Lentz indicated that his solution is geometrically different from Alcubierre’s and most others because of how the energy is kept around the warp bubble. In the Alcubierre solution, the energy density and curvature are maximally separated, with energy confined to a small torus between regions of high contraction and expansion.
In Lentz’s proposal the curvature and source are instead highly correlated with regions of high energy density and high expansion and contraction. It is these geometric differences between his concept and conventional concepts that make Lentz’s proposal a potentially more viable warp solution than those previously proposed. Of course, Lentz’s warp drive is still purely theoretical. However, he sees some steps that can be taken immediately to try to bring his version closer to reality, which, like all previous drive theories, involves reducing the amount of energy required.
Where does Lentz want to take his warp drive from here? The next goal, he said, is to create a warp bubble capable of operating at 1 percent of the speed of light using a modern-day fission reactor. The physicist said he would consider patenting his warp drive, but made it clear that his work was only one part of a larger, rapidly growing body of work in this area and new warp drives since Alcubierre’s 1994 proposal.