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Originally Posted by Weltevreden SA
Astrophysics treads warily on the terrain of literary techniques such as metaphor, simile, allegory, and so on. Astronomers are not noted for taking liberties with the limits of lateral thinking. Yet unwittingly they do it all the time. Black holes, for example, convert the rapid exchange of matter density into energy density using mathematical analogs of magical transformation. These are called Lorentz transforms. Graduate students assigned the task of calculating them consider the duty a form of ritual sacrifice. These students also have an odd fondness for old films which feature maidens, volcanoes, and scowling old men with short spears.
Core collapse Type II supernovae have poorly explored literary analogs. Any star which acquires more than 8 times the Sun’s mass will eventually self-destruct in a giant explosion. Here is the screenplay scenario: Consider the the fate of a glutton at a banquet: he piles too much on his plate and then wolfs it all down, which typically results in an urge to leave the table in a hurry. Similarly, a gluttonous category of overweight star called a Wolf-Rayet ingests massive amounts of cabbage and beans from a nearby nebular salad bar (hydrogen and residual metallicity in a contracting Bok globule). In no time the W-R realizes it has gained too much weight (envelope mass) for its core capacity (hydrogen fusion). Whereupon the W-R goes on a crash diet and sheds roughly sixty percent of its mass in an enormous cloud of gas. The tableside companions have an earthier term for the result: Fast Acting Rejection Thermodynamics. This plot device is as old as Thucydides: it is Fate that dooms you, not the way you behave. A Wolf-Rayet is fated to self-annihilation no matter what it does to reform itself. Morality melodrama is an inexplicable fixation in Western thinking. In no other world culture do we find so many tales of self-destruction by self-indulgence. Every astronomer will tell you that the most abstemious stars live the longest.
Another class of supernova, Type 1a, is a morality tale involving the rich robbing the poor. These occur in my house all the time in the form of thermodynamic mass-energy transfer between two cats and one food dish. (The quantum physics explanation is that no two particle-energy states can occupy the same place at the same time; this does not cut much ice with cats.) My neighbour’s cat likes to steal food from my cat’s dish. Meanwhile, my cat is doing the same at his house. However, if they try to occupy the same food dish at the same time, the result is recorded as a feral detonation by two aural-band energy detectors in my head, via the distinctive spectral signatures of hisses, yowls, and thumps. In stars up above, a similar process is at work. One star steals mass—gas—from the surface of the other and adds it to its own waistline. If it’s a specific type of star, a white dwarf, it will reach a point where it has simply out-eaten its own capacity, and iron-dissociates into total destruction. (Intense energy and pressure can dissociate an iron atom into eleven helium atoms and an enormous amount of energy—that is why helium overabundance is the hallmark of Type 1a spectra, while iron is the signature of Type II.) The begrieved companion star receives a colossal kick in the behind as a thank-you-very-much and skulks off to get over it in a different part of the galaxy. This is analogous to a wastrel lass moving to a new town and starting over as a virgin. The physical evidence of this type of supernova—a distinct light curve seen by witnesses all over the universe—has its analog in the physical evidence of the explosion at my household cat dish. Next morning the spectral signatures of the encounter easily tell me which star exploded and which skulked off: the colour of the fur on the floor. My cat is gray, the neighbour cat is black. Alas, however, unlike their stellar colleagues, earthly cats don’t just end it there and be done with it. Not hardly! They wait all night long for the next matter-to-energy transfer, and sniffily leave me to tidy it up in the morning.
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WHOOOAAA. You have just blown my mind
THanks for the insightful metaphors of astronomy and astrophysics!!! I think some of this can be very useful. I have a discord between rich and poor in this particular story and may be able to hijack your Type 1a supernovae analogy. Royalty cheque's in the mail if this ever gets made
