Mike McCulloch, from Plymouth University in the UK, has revealed a theory that tries to clarify how this physics-breaking method of travel could really work. And his notion has some proponents of this technique of transport rather thrilled. EM Drive actually is, in short, is a propellant system that could allow us to travel our universe in ways that, today, we can just dream about… but Em Drive could make it happen.
Image Credit: Elvis Popovic
It works with the help of microwaves. According to the recent claims, you bounce microwaves back and forth inside a condensed cone, and the outcome will be a thrust in the direction of the narrow end of the cone. That looks simple enough, yes? But there is a catch: The overall momentum increases as the device starts to move. That is like putting yourself inside a box, pushing on one side, and producing thrust. Yeah it does sound silly, doesn’t it?
Well, here is another catch: So far, a number of research groups around the world have assembled their own forms of the EM Drive. And they actually produce thrust… but only a small amount. Scientists have no idea where this increased momentum comes from.
But the new hypothesis that could explain EM Drive revolves around inertia. The thrust produced by the EM Drive has to do something with 'the Unruh effect'.
According to 'the Unruh effect, an accelerating object experiences black body radiation, meaning that the universe heats up when you speed up. And in this respect, according to McCulloch, inertia is the pressure the Unruh radiation applies on an accelerating body.
According to MIT notes, "at very small accelerations, the wavelengths of Unruh radiation become so large they can no longer fit in the observable universe. When this happens, inertia can take only certain whole-wavelength values and so jumps from one value to the next. In other words, inertia must quantized at small accelerations."
Therefore, the inertia of photons that are enclosed in the above-mentioned condensed cone have to change as they bounce back and forth. And to preserve momentum, this must produce a thrust.
Thus, the inertia of photons that are inside of the aforementioned truncated cone have to change as they bounce back and forth. And to conserve momentum, this must generate a thrust.
RIT astrophysicist Brian Koberlein explains:
“The Unruh effect (basically) says that an accelerated object should see a thermal background due to background quantum fluctuations. The calculation of the Unruh effect is straightforward, and isn’t controversial. Unruh radiation is (basically) the idea that in the detection of this thermal background you can trigger the emission of real particles. In other words, can you create real radiation ‘out of the vacuum.’ So they are claiming Unruh radiation is real, and causing the EM effect.”
Researchers are still skeptic about this theory as the quantized inertia notion at least creates some predictions that can be tested but this does not mean that it is accountable for the thrust that is observed in relation to the EM Drive.
Mike McCulloch originally devised this theory to explain "flyby anomalies". In December 1990, as the Galileo probe flew past Earth on its way to Jupiter, its speed unexpectedly jumped by 4mm/s. Then again in January 1998, Nasa's Near spacecraft’s speed rapidly jumped by 13mm/s as it swung past Earth. The same occurrences were also observed in 1999 with the Cassini spacecraft and in 2005 with the Rosetta spacecraft.
These happenings are called "flyby anomalies" and no one has any idea why they occur. McCulloch was trying to solve this with quantized inertia.
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