The Strange Mystery of the Golden Stars.

We live in a universe that can be expressed, or described mathematically, at least to a degree. Indeed, some form of math is something we probably would have in common with other technological alien species in the universe. You're going to need science, math, and engineering to send or receive a radio signal, of obvious technological origin for example. How that math is expressed is going to be different of course, aliens won't have the greek alphabet or our human mathematical symbols, but they will need an equivalent in order to build a radio transmitter or even know to do so. It has to be said that for the vast majority of human existence, we had no idea radio existed. While the universe at large has bombarded us with radio waves for the lifetime of this world, ancient civilizations like the Roman Empire had absolutely no idea that radio existed. Yet now, the vast majority of humanity knows radio, and uses it alongside mathematics. It could be said, however, that the universe itself doesn't care about mathematical concepts, it's merely thought that it can be described using them, usually. But inherently it isn't mathematical, rather it is what it is, and sometimes that line gets blurred. Occasionally the universe will do something so mathematically complicated that it doesn't seem right, and math may stop predicting how the universe is, just look at quantum mechanics. On that level, the universe throws curve balls, and says it may not be as mathematically beautiful and simple as some might wish. But sometimes the universe goes the opposite way and produces something so beautiful and elegant that it almost seems like it shouldn't get to that level. In this case, we're talking about something called the golden ratio. For people interested in mathematics, the divine ratio, as it's sometimes called, starts with phi, sometimes called the most irrational number, 0.61803398875. It's also given as the inverse of that number, 1.61803398875. That's important later. To people interested in human art, the golden ratio is often used by artists and appears in those of Leonardo da Vinci, and Salvador Dali, and a good many others. During Leonardo's time, the ratio was known as the divine proportion, and to visualize it, if you take a rectangle proportion to the ratio, and then divide it into smaller and smaller rectangles, and you get the golden or Fibonacci spiral. Then, you use this to create the proportions of your artwork, the end result being pleasing proportions to the eye, or so it's said. It's been suggested that even ancient architecture like the Parthenon in Athens conforms to this, and that the ancient Greeks certainly knew of the concept. But that's humans and what we find visually appealing. Nature doesn't care about that. Or rather, it shouldn't. Yet, the golden ratio also appears in nature. The patterns and ratios of the Fibonacci sequence and the golden ratio are commonly found in nature, though to be fair there are plenty of other patterns that don't fit. Examples of the golden ratio in nature would be nautilus shelves, arrangements of flower petals, and sometimes even spiral galaxies, though not all galaxies are spirals, far from it. So sometimes it's there, sometimes it isn't. The point here being that this occurrence of the golden ratio in nature, and also mathematics and human art and architecture, is something that seems sort of oddly universal, at least to a degree. Aliens doing math probably would know this, and even see examples in nature as they see it. If it happens here on our world, and from our perspective, then why not them? Could they then understand some aspect of our art? This means that the golden ratio could serve as a common signpost that all civilizations capable of doing astronomy, physics, art, and architecture would recognize. So, like the 1420 megahertz hydrogen line, which serves as a natural signpost frequency, due to it being the frequency at which neutral hydrogen emits radio, and being the most common element in the universe anyone with science would know about, the golden ratio can conceivably do something similar. So, do we see the golden ratio in nature where we really shouldn't? Is there an equivalent of a wow signal here? The answer is potentially yes, but very likely no. Our galaxy, and indeed other galaxies, are full of stars that pulsate. They are very common. Known as variable stars, these stars are enormously useful in probing the universe. Indeed, the discovery of a Cepheid type variable in the Andromeda galaxy in 1923 by Edwin Hubble changed everything. It showed that there were more stars out there than just those of our own galaxy, and ultimately indicated that the universe was indeed expanding and was astonishingly vast, something a lot of astronomers in those days rejected as preposterous. It wasn't, it was reality. One specific type of variable stars of interest here are known as RR Leary stars. These are old stars that have left the main sequence and passed into the red giant phase. These stars burn helium in their cores, and at a certain stage they begin to pulsate due to pressure differences in the inner parts of the star. RR Leary stars tend to pulsate very characteristically, with a main pulse and a secondary one. Indeed, this is thought to possibly be the future of the sun. As it leaves the main sequence, it may begin to pulsate and become an RR Leary variable star. Imagine that, a giant red sun changing radius as it pulsates over a 12 to 24 hour period, gaining and losing as much as 20% of its size. But there's something else odd about these stars. In a paper by John Linder and colleagues, link in the description below, they surveyed six RR Leary variable stars and found something interesting. In four out of the six stars, the ratio between the main pulsation and the secondary was very near the golden mean. Not exactly, which could be important here, but very near. But there's more, in stars that exhibited the golden ratio, they also exhibited fractal behavior, which may indicate another pattern. But, the researchers note this is a small sampling and more observation is needed. While these patterns are very likely natural, and very interesting in that sense since they promise to reveal new clues about stellar dynamics, there's another aspect here hidden deep within the world of SETI. This idea involves Cepheid variable stars, but should also potentially be applicable to RR Leary variables, and promises a way of affecting variable stars technologically in order to produce patterns that might allow for an easy way for alien civilizations to communicate over vast distances. Given that these stars can be used to gauge distance in the universe, then it seems likely alien astronomers would be aware of and study them. It has been suggested that if you inject a relatively small amount of energy into a variable star at just the right time, neutrinos seem ideal here given their speed and penetration ability, you could manipulate the variations in the star. Done correctly, some of these induced variations might be very unambiguous and very indicative of technology. Moving further, this might provide at least a method of signaling that you exist, or more broadly, communication. This has the advantage that variable stars already exist, you would merely be tweaking them, and they are visible over very long distances. In a sense, this would be a far easier method of communication than setting up a huge radio beacon. So here's the big question. As the sun ages, if we are still around, we will need to do some serious work in order to survive. Firstly, the sun's luminosity continues to rise. So within about 600 million years, we will need to mitigate the effects of that. This is, on its face, simple. We could get a lot of mileage as far as mitigation out of putting up a sunshade in space to block out some of the sun's increasing light. In practice however, this probably would present significant engineering challenges, but given that if we are still around millions of years from now, it's a problem we will need to solve no matter what. Or will we bother? Might it be simpler to just close up shop in this solar system and move to another? Perhaps we would migrate to a planet around a long-lived red dwarf that has quieted down that we can terraform into a new earth, or for that matter many planets in many star systems. Maybe the last duty of the sun to the life it spawned in this star system will be to become a pulsating red giant, tweaked by its former residence to pulse out a pattern, perhaps the golden ratio, to tell others that life was once here and they were not alone. Thanks for listening! I am science fiction author and futurist John Michael Godier currently answering an audience question. I was recently asked because of my ten list regarding setting messages that we may not want to receive, which one I may not want to receive. That's easy, a clip from one of my videos. It would be very disconcerting indeed if the message said live. And be sure to check out my books at your favorite online book retailer and subscribe to my channels for regular, in-depth explorations into the interesting, weird and unknown aspects of this amazing universe in which we live.