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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 (and typically, though not entirely, larger and heavier), 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 are large objects that do not suddenly and drastically change form.[citation needed] (Although, almost all matter on Earth, including iPhones, contain some atoms that are radioactive and exhibit nuclear decay, mixed with a non-radioactive majority.)
The iPhones in the comic undergo two different types of decay, which mirror two types of nuclear decay:
- In alpha (α) decay (vertically downwards, in the diagram) the model number changes 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+). No evidence is given as to how the respective masses of the phones actually changes in this analogy.
- In beta minus (β-) decay (a rightward-and-upward step) the iPhones undergo a version upgrade, but also the removal of a brand name modifier (usually denoting additional features included within the same model range), leaving them closer to that new range's most basic model. 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. 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.
The specific reason for the decay chain stopping at iPhone 7 is unknown. A possible reason for this is because lithium, which is often used in phone batteries, has the stable isotope lithium-7. "Stable" may refer to the usability of the device in terms of whether or not it still receives security updates, but the iPhone 6s also received the latest security patch as of the time this comic was published. Apple has paid significant compensation regarding one of their business practices of intentional obsolescence. Alternatively, Randall may be suggesting that models up to iPhone 7 were highly reliable, but that models beyond that have become ever more problematic - this would mirror the case of radioactive decay, where it is the higher numbered elements that are unstable.
(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 occurred, 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 physics processes (in this case in 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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