2504: Fissile Raspberry Isotopes

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Fissile Raspberry Isotopes
Grandma's shelf-stable blackberry pie meson recipe was a huge seller until her farm was shut down by a joint FDA/NRC investigation.
Title text: Grandma's shelf-stable blackberry pie meson recipe was a huge seller until her farm was shut down by a joint FDA/NRC investigation.


Ponytail is admiring her raspberry fields telling Cueball she expects a good harvest... That is if they do not get too many fissile raspberry isotopes! To which Cueball has to ask Too many whats?

The comic is thus a joking analogy to nuclear chain reactions, in which the fission (splitting in two) of one atomic nucleus releases neutrons, which then strike other nuclei and cause them in turn to fission, releasing more neutrons. This chain reaction releases a great deal of energy and is what makes possible both nuclear power and nuclear bombs.

A fissile isotope, such as uranium-235, is one that is sufficiently large and unstable to undergo such a chain reaction, as opposed to the more common and less unstable uranium-238. Ponytail fear that her raspberries have too many unstable isotopes so that her fields risk undergoing a similar fission-driven chain reaction. This chain reaction is depicted in the second panel, and she explains that if this happens the entire crop may be gone in seconds. It sounds like this is only dangerous for her economy, i.e. all the berries destroyed, but not a runaway explosion that destroys her field and any living thing nearby.

In real life, raspberries don't undergo such chain reactions.[citation needed] As an aggregate fruit, raspberries (as well as blackberries mentioned in the title text) resemble common depictions of atomic nuclei, with each drupelet corresponding to a nucleon (proton or neutron), which is probably why they are the subject of the comic. (The actual "appearance" of atomic nuclei, in contrast to the common depictions, is complicated by Heisenbergian uncertainty, quantum effects, and strong nuclear force interactions.) Perhaps these raspberries are byproducts of the experiments depicted in 1949: Fruit Collider.

This comic is also a pun on "pi mesons" or pions, subatomic particles that transmit the strong nuclear force, and the similarity in name to a pie, the food type, as in a raspberry pie. The transmission of the strong nuclear force happens most importantly in the atomic nucleus and is responsible for keeping the nucleus intact, i.e., preventing it from undergoing fission despite the strong repulsive electromagnetic force present from all the positively-charged protons.

Raspberry pies (and pie mesons of such) are not to be confused with Raspberry Pi, a very popular microcontroller widely used for hobbyist or educational projects.

Ponytail claims that her berries are protected (bound) by fresh raspberry pie mesons. Cueball states he hopes they hold, but Ponytail is confident as these pies are made from her grandma's recipe, i.e., it is actually a fresh pie made from the berries. The faith in the pie recipe being able to impede the danger references the convention of "Just like Grandma used to make", nostalgia for an infallible cookery ancestor, in this case a hallowed family recipe that acts to mitigate any budding 'berry' chain-reaction. Grandma's baking is not always so fondly remembered and, in this case, it could be some (in)famous inertness and solidity to the product that is reassuring, not any form of culinary excellence.

The title text mentions that the grandma's "blackberry pie meson" recipe was a huge seller, but that then the farm was shut down by a joint FDA/NRC investigation. This refers to the Food and Drug Administration (FDA) and the Nuclear Regulatory Commission (NRC). The FDA is responsible for the regulation and inspection of food in the U.S., and the NRC for the regulation and inspection of nuclear facilities and materials. A hypothetical "blackberry pie meson" might well run afoul of both, being both nuclear and therefore subject to NRC regulations and permitting requirements, and unhealthy to eat and thus violating FDA rules. This could in addition also violate the FDA's rules on radiation emitting products. One might be able to imagine the FDA discovering that the blackberry pies are functioning to contain a nuclear chain reaction, and calling in the NRC to consult. The FDA took a similarly incongruous interest in physics in the title text of 2216: Percent Milkfat.

It is mentioned that the pies were shelf stable, which means it can last a long time without being in a refrigerator. This may be because of its innate radioactivity keeping it free from germs. This may also explain why they were shut down by both the above-mentioned agencies. The word "stable" also describes atoms, and therefore substances, that do not spontaneously undergo nuclear decay, though a stable isotope may (eventually) result directly from the decay of an unstable one.


[Ponytail and Cueball are standing in a field, looking at rows of crops disappearing in the distance over rolling hills.]
Ponytail: I reckon it'll be a good harvest.
Ponytail: So long as we don't get too many fissile raspberry isotopes.
Cueball: Too many whats?
[In a half height panel is shown a picture of a raspberry with an arrow to a situation where it is splitting in to two equal parts. From the split there also comes two small drupelets flying out as shown with arrows. Below these two situations is a smaller sketch of how one of these two drupelets will eventually hit another raspberry, which will send out three drupelets when splitting, two of those hitting other berries, that each send out two drupelets. The lower of these are not depicted hitting any, but the upper split hits two again, which each send out two, in an ongoing chain reaction. The depiction stops there. Above this panel is what Ponytail tells Cueball:]
Ponytail (narrating): If a raspberry breaks in half, it releases fragments which can cause more splits. Within seconds you've lost the whole crop.
[Ponytail and Cueball are standing in an empty panel talking.]
Ponytail: Luckily the berries are bound by fresh raspberry pie mesons.
Cueball: I hope they hold.
Ponytail: It's my grandma's recipe. They'll hold.

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This joke is like a visual pun, a raspberry fruit looks sorta like a nuclear model, and so it behaves the same (ie can go supercritical). 20:38, 18 August 2021 (UTC)

Along with an actual pun: pi in "pi meson" sounds like pie in "raspberry pie". Barmar (talk) 20:43, 18 August 2021 (UTC)
If it isn't also an intentional tertiary reference to the Raspberry Pi computer board, I'll eat my hat! 21:22, 18 August 2021 (UTC)
I'd say you would have to eat it. Cannot see what this comic has to do with a computer board, just because it is named after a raspberry pie. This joke is obviously about the berries looking like nuclear cores, and pie mesons. Not about anything with a computer. So take some salt an eat (or swallow one the hats in your link, along with a camel :p ) --Kynde (talk) 10:21, 19 August 2021 (UTC)
I interpreted 'tertiary' to mean that randall was 'primed' to talk about raspberry pies due to his exposure to the board, and similarly for readers finding it interesting and humorous. Baffo32 (talk) 08:28, 20 August 2021 (UTC)

Though raspberries resemble the common depiction of nuclei, perhaps we need to explain that in reality, nuclei are rather different..? BunsenH (talk) 03:41, 19 August 2021 (UTC)

I think anyone reading xkcd and this page, will figure it out via the links ;-) --Kynde (talk) 10:21, 19 August 2021 (UTC)
I tend to forget that nuclei aren't little raspberries made of nucleons, even though I used to be a fusion researcher. In fact I'm sure I was only ever half-aware they weren't (I didn't study the actual nuclear physics, ok!)... so +1 from me in favour of adding a bit about the 'real' nature of nuclei, that would be interesting. --192·168·0·1 (talk) 09:39, 20 August 2021 (UTC)

I would suggest referring to the raspberry parts as 'drupelets' rather than 'ovaries'. 12:58, 19 August 2021 (UTC)

I love eating the juiciest and sweetest of fruit ovaries, raspberries and strawberries are my favorite but I also enjoy apples and grapes --Lackadaisical (talk) 17:29, 19 August 2021 (UTC)
I looked this up briefly and I _think_ that the ovaries are what develop into the drupelets, here, not certain, judging by phrasing on wikipedia. So I changed it. Don't eat the ovaries, eat the part that's designed for eating. Baffo32 (talk) 08:37, 20 August 2021 (UTC)
Fine but you forgot the transcript. I have changed it there so drupelet is the word used. --Kynde (talk) 15:57, 20 August 2021 (UTC)

The page says "Of course, in real life raspberries don't do that.[citation needed]" - where is one supposed to find a useful citation to state that fields of raspberries don't explode? 22:18, 19 August 2021 (UTC)

That’s the point! 02:55, 20 August 2021 (UTC)
It's a joke, and you are free to remove it if you so judge. Others may disagree. Sometimes raspberry farms have some pretty hard to describe explosive activity when their parts combine in rare chain reactions. Baffo32 (talk) 08:39, 20 August 2021 (UTC)
It's a reference to 'xkcd 285', a long running joke in the xkcd community, What If? and Randal's other books, and the xkcd merch shop (talk) (please sign your comments with ~~~~)
And severely overused. Imho it should only be used when we are actually looking for a citation for someting stated without proof in the explanation. So I generally feel free to remove them as I did here. --Kynde (talk) 15:54, 20 August 2021 (UTC)
I agree there can (and has been) overuse, but by your criteria there would be absolutely no 285-backrefetencing at all. In use on The Original Wiki and all the rest there other cite-markers requesting an edit to clarify, expand, use better units, add comic issue and page, etc, and th9se exist (or can be made to exist) here.
I wouldn't suggest every clause of every sentence of every paragraph of every comic's explanation be in-joked, but (with exceptions on a very few rare occasions that will doubtlessly be edited down by a future editor like you, or me, anyway) I see no harm in so labelling up to one axiomatic statement this way per article (the absolutely most obvious and inarguable and, by editors' aggregate concensus without resorting to an edit-war, humorous-to-so-label statement).
By dint of the humour-decay so described, results in one permanent example fit to tickle the funnybone of all but the most curmudgeonly every 2, 3 or 4 comics, on a rolling average. In every case being absolutely obvious to pretty much everyone that it is there for amusement value (especially amidst dry, technical detail) even to those only just arrived upon these particular digital shores...
IMO, of course, having no authority or desire for authority here. 17:30, 20 August 2021 (UTC)
I'm pretty sure part of the joke here is the edit war it can stimulate, not sure. But clearly it would be overdoing it to formalize including one every single explanation. Baffo32 (talk) 00:13, 21 August 2021 (UTC)

I feel like there might be more to this joke. When I'm plucking raspberries in the forest, they break in half pretty often, causing me to get juice on my hands, which is pretty annoying. 21:42, 20 August 2021 (UTC)

And then that juice on your hands breaks another raspberry in half, because you are worried less about keeping your hands clean ... and then you hand your juicy raspberries to a friend, getting their hand juicy from your hand ... The NRC arrive and it's just red, everywhere. Baffo32 (talk) 00:16, 21 August 2021 (UTC)

If a Raspberry breaks, germs can better feed off the fruit and multiply then decompose nearby fruits. The title text states blackberries, not raspberries. Mesons consist of quark and antiquark. Quark is a dairy product used as ingredient in baking pies. 13:33, 21 August 2021 (UTC)

Can't believe that the Raspberry Pi is not implicated here, but personally I can't see the connection. Can someone? Asimong (talk) 17:33, 23 August 2021 (UTC)

It's talked about above. Maybe there wasn't room for a microcontroller-based allusion (after helping sparking the base word-association that begot the comic's final target), or maybe it's totally coincidental to the original inspiration and had not enough commonality to suggest bringing it into the fray. I can't believe it did not cross Randall's mind somewhere along the way, though. Perhaps its lack of intricate tying-in is more indicative of it being actively not shoehorned in. (Every idea I have about how to cameo the Pi seems rather clunky to me, at best. But then I'm not a polymathic parodist of long standing...) 11:59, 27 August 2021 (UTC)

I thought it was a miss that it wasn't pie masons (as in mason jars... frequently used for preserving fruit). WileyC (talk) 02:02, 9 September 2021 (UTC)