Researchers Find the New-Fastest Way to Generate Random Numbers

Image Courtesy of Wired

By Garrett Farrell

Hfndjfblfbabanbflanbglahvoahbghabfhabouygtjbhv. When I typed out that “word,” I did not pay any attention to the letters I was typing or to the order in which I was typing them. Although I typed these numbers in a random fashion, because of human nature it is more than likely that the sequence is not “truly” random. 

The problem of true randomness is one that has existed for thousands of years, and for generations scientists have been struggling to find ways to generate random numbers faster. Last month a team of researchers announced that they had found a way to generate random numbers quicker than ever imagined.

In a study published in the prestigious journal Science, Dr. Kyungduk Kim, an applied physicist from Yale, and an international team of researchers described the experiment and the design of the new generator. While the machine is incredibly complex, its design is surprisingly elegant: essentially, a laser is fired into an hourglass shaped cavity with mirrors at each end. The beam of photons that is emitted steadily interferes with itself, so that both the frequency and intensity of the light that emerges from the cavity are irregular. In layman’s terms, this means that researchers were not able to predict where light would appear, and how intense it would be. 

The researchers used a high speed camera to track where the light appeared and its intensity over a grid of 256 squares, and used the information of any given frame to assign a bit value to that frame. Although the intensity of light may sound like a subjective measurement, there is actually a unit, called the candela, that scientists use to measure an objective intensity of light: one candela is simply defined as the amount of energy a source of light gives off in a set amount of time over a solid arc. More technically, a candela is defined as the luminous flux of a light source per steradian. 

Now, the questions I’m sure you’re all asking yourselves: exactly how fast is this random number generator, and why should I care. 

To answer the first question, let me give you a comparison: the fastest speed Usain Bolt has ever achieved is 44.72 kilometers per hour, which translates to .27777 meters per second. Assuming that Bolt is consistently traveling at this speed, it would take him roughly .9 seconds to travel a quarter of a meter. In the time it takes Usain Bolt, the world’s fastest man, to travel one quarter of a meter, this random number generator will have already generated 228.6 TRILLION random digits. Not only is that a mind boggling feat, it is roughly ten times faster than the next fastest random number generator.

Now, why should you care? Truly random numbers are growing more important every day, especially with quantum computing on the horizon. In fact, a random number problem was used to “confirm” that Google’s quantum computer had achieved supremacy over traditional computers. Random numbers are essential to encryption, and have applications in areas such as gambling, statistical sampling, and search algorithms. The multitudinous applications of random numbers are why the news of a generator this fast is so groundbreaking, and why it will have a far reaching impact in the future.