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| Decay Chain |
 Title text: If you have an old phone in a drawer, and you listen very carefully, you can occasionally hear the occasional tap of an emitted SIM card hitting the side of the drawer as the phone transmutes to a lower-end model. |
Explanation
This comic is a play on nuclear decay chains, the series of radioactive disintegrations that the nuclei of unstable atoms undergo. Example diagrams of such nuclear decay chains can be seen here. This comic suggests that as iPhones model iterations get higher, they, similarly to heavier chemical elements, become unstable and susceptible to decay into lesser models. Some isotopes of atoms decay into other isotopes, releasing particles in the process. This process is generally dictated by the number of the positively charged protons in an atomic nucleus, which dictate its chemical identity, and the neutrons, which keep the protons in as stable a clump as possible. Particular isotopes, increasingly so for heavier atoms, are known to be subject to one or more modes of nuclear decay in order to attain a more stable and simpler form, including by several such steps. This comic humorously explores how an iPhone would decay if decaying worked similarly, which is absurd as iPhones aren't subject to atomic decay. (Almost all matter on Earth, including iPhones, contain some atoms that are radioactive, mixed with a non-radioactive majority.)
The difference between iPhones undergoing alpha (α) decay (vertically downwards, in the diagram) is the change in model number from a higher one to a model two steps lower, except for the step involving the iPhone X which apparently exists instead of a "9" model. This is equivalent to the change in atomic number when two protons together with two neutrons leave the nucleus in the form of a helium ion (He2+), known as an alpha particle. The atomic number of such atoms reduces by two and the mass number reduces by four (that held by the departing He2+), though no evidence is given as to how the respective masses of the phones actually changes in this analogy. The specific reason for the decay chain stopping at iPhone 7 is unknown, although a possible reason for this is because lithium, which is often used in phone batteries, has the stable isotope lithium-7.
The process of beta minus (β-) decay (in elements, the effective conversion of a neutron into a proton and a free electron) raises the atomic number by one by transforming a neutral particle to a positive one via emission of a small negatively charged beta particle (an electron), leaving the mass only slightly decreased. In the terms of iPhones, this is represented by the removal of a brand-name modifier (usually denoting additional features included within the same model range) in order to perform a version-upgrade but now being closer to that new range's most basic release of model. This is represented by a rightward-and-upward step. The decay step from the iPhone 13 Pro to the iPhone 14 Plus, which is missing a symbol, is clearly one of the β- decay steps.
(After alpha or beta decay, atoms may then emit gamma radiation (high-energy photons) as they rearrange their atomic state without changing their composition, but this process does not change the element in any meaningful way. It also will occur when neutron capture and/or atomic fission has occured, which is generally considered outside the natural decay chain of any such isotope, and can also result from nuclear fusion. Beta decay also requires emission of an antineutrino, but that particle interacts so weakly with matter that it's undetectable except by extremely sensitive experimental equipment.)
The title text suggests that the "alpha particle" of the iPhone is a SIM card, and that alpha-decaying phones will emit one of these with each decay (despite few phones having more than two, and most working ones only having one, but perhaps that's part of the mystery of telephonic transmutation). The sound of an old phone, sitting in a drawer, ejecting the unnecessary SIM is likened to the slow click of a Geiger counter registering the decay particles ejected from a decaying radioisotope. Radioactive decay is a random and spontaneous process; without the sound, one would never otherwise know if the phone even had decayed without opening the drawer to find out.
A similar comparison between smartphones and stars happened in 1422: My Phone is Dying.
Transcript
[A flowchart with arrows leading from a circle with the words "iPhone 16 Pro Max", to circles with other iPhone names, eventually leading to a circle with the words "iPhone 7"]
- [Caption below the panel:]
- Physicists believe that an iPhone 16 Pro Max will, if left alone long enough, eventually decay into an iPhone 7, the heaviest stable model.
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