It is very difficult for the non-scientist, non-mathematical mind to comprehend the concept of Einstein’s E=mc2: “The mass of a body is a measure of its energy content” (his own words, highlight mine), but it will be less difficult when we add the “body”, the System, as a fundamental part of it (S[e=mc2]).
The vast distances between the planets, between the stars, between the galaxies, are difficult for the human mind to comprehend. And so to have a vague sense of what those distances are, let us review some of the information we already possess starting with the picture below taken by the Cassini Spacecraft in 2013, which shows Earth from the rings of Saturn as a tiny spec of light (click on picture to enlarge).
Since the orbits of the planets around the Sun are ellipses, the distance between Earth and Saturn when closest to each other is approximately 1.2 billion kilometers (746 million miles), and when farthest from each other is 1.7 billion kilometers (1 billion miles). To simplify these enormous distances between the bodies of our Solar System, Astronomers use Astronomical Units (au) which is the average distance from Earth to the Sun at 150 million kilometers (93 million miles). And so the average distance from Earth to Saturn is a mere 10 au, as compared to the distance from the Sun to the Heliopause at 100 au (see chart below showing Voyager 1 traversing the Heliopause in 2014 after 36 years of travel), and the distance from the Sun to the Oort Cloud (the theoretical boundary of our Solar System) at ~100.000 au.
To simplify the astronomical distances beyond our Solar System, Astronomers use Light Years which is the distance Light travels in a year at 299,792 kilometers (186,000 miles) per second. And so, for instance, the distance from the Sun to the farthest edge of the Solar System is 0.3 light-years, and the distance from our Sun to our nearest star, Alpha Centaury (a binary star system), is 4.3 light-years.
When we consider all together 1 – the vastness of our Solar System, 2 – the fact that the Sun holds 99.8% and the planets, moons, asteroids, etc., 0.2% of the mass content of the entire System, and 3 – the fact that the rest of the Solar System, what we call ‘the void’, is the energy content the System exerts … the pull and push … to sustain relative equilibrium as a cohesive unit, we can then begin to glimpse at the meaning of the quantities in Einstein’s equation: The mass content of the Solar System, 1.0014 solar masses, times 299,792 km (186,000 ml) squared, is the relative measure of the energy contained in a bubble with an estimated diameter of 200,000 au (see picture below).
Our Sun is an average-sized star, with other stars in our galaxy 100 times more massive and others just 1/10 of its mass, and it is 4.3 light-years away from our closest star, Alpha Centaury. If we assume 1 – that to be relatively stable each star must maintain a distance from its neighbors proportional to its mass, and 2 – if we take the number of stars in the Milky Way at 200 to 400 billion embedded in a sphere estimated to be ~180,000 light-years in diameter, we can then begin to fathom the content of the vast voids between its stars … what we currently call “dark energy or dark matter” … which is the equivalent energy the galaxy requires to survive while spiraling through space as a cohesive unit.
Now, considering 1 – that the Milky Way and Andromeda are currently about 2.5 million light-years apart, 2 – that our Universe has, at least, 100 billion galaxies embedded within an oval bubble estimated to be 93 billion light-years in diameter … and expanding … and 3 – that if all those galaxies are separated, like the Milky Way and Andromeda, by distances proportional to their mass, we can then begin to fathom the contents of the immense voids between them … what we currently call “Dark Matter or Dark Energy” … which is the energy the Universe requires to survive as a cohesive unit, while it has been unfolding across eons and eons of time into manifold levels of complexity and order.
These figures are staggering … incomprehensible to the human mind … and are, as we know full well, subject to revisions as technology improves. And yet they are even more staggering at the other end of the spectrum; there are, for instance, an estimated 32.7 trillion cells in a human body with ~86 billion neurons in the human brain, and each neuron has an estimated ~200 to ~700 trillion atoms, and each atom is a pocket of relatively minute mass and enormous energy content … think Hiroshima.
Things in our Universe are mostly made out of energy, and we are no exception. That is the reason why we can move our bodies to accomplish incredible physical and mental feats … climbing Everest; engendering and raising a progeny; landing a man on the moon; imagining, as Einstein did, the proportion of energy to mass in our Universe; seeing, as Darwin did, the unfolding of Evolution through creativity in adaptation, or simply getting up each morning to face the world. But this is a subject for another post.
It is incontestable that we are immersed in a fantastic, immensely creative, adaptable, self-organizing, self-generating Universe, and that we are, as far as we know, the only beings becoming more and more consciously aware that, with about 86 billion neurons in our brains, we are like the first little neuron in a developing infant which, upon the first days after birth, begins to build the web of interconnections that ultimately brings the conscious self-awareness of the world within its own and beyond its own.
Our quandary is that we have fields of inquiry searching for the smallest particle, and other fields searching for the farthest object in our Universe. And unless we integrate them into one field of inquiry; a field encompassing the microcosm and the macrocosm and the world in between … the world of our experience …. we will never be able to see the astonishing, self-creating beauty of the Whole Being from which we are made and within which we are immersed.
And so the beauty of Relativity we are not yet aware of, is that it unites every single body in our Universe … without regards to levels of complexity, and from the infinitesimally small to the infinitely immense … with the common urge to survive, whether by instinct or conscious self-determination, through the attainment of the equilibrium embodied in the equal symbol of (S[e=mc2]); “The mass of a body … or system … is a measure of its energy content”.
Source of pictures: Internet sites (earth-from-saturn-900Mmiles-cassini.jpg), (Voyager-1-Goes-Interstellar.jpg), (kuiper_oort.jpg)
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