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16 Answers 16

up vote 9 down vote accepted

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Which properties of wood do I quantify for damage calculation for a shield?

Italicized text is for Sandbox: I'm not entirely sure where this question would go because it possibly falls under the domain of several Stack Exchange sections. It was recommended I ask here in the Sandbox by someone on the Meta Stack Exchange. Someone else recommended the Engineering Stack Exchange with the materials tag.

For a medieval fantasy themed RPG I'm working on, I'm building a semi-realistic crafting system where the properties of the materials you use determine the stats of the completed item, with materials being interchangeable for people to tinker with. The stats are tied directly to the materials, the schematics determine how those stats are applied to the output item.

In my research on various woods, I've found a few numbers that look useful and recorded them on a spreadsheet:

I'm trying to figure out how those numbers would apply to damage calculation for the following stats:

  • Durability
  • Blunt resistance
  • Piercing resistance
  • Slashing resistance

Ideally, I want to simplify the numbers on the materials to those properties or numbers the crafting schematic can apply those numbers to determine the damage those stats.

These shields will be layered with other materials as real shields are, but for the sake of this question, our focus is only on the wooden layer of the shield.

Damage will be loosely based on the pressure applied to the shield, meaning the force of a piercing attack will be focused on a point, sword attacks will be along the edge of the blade and blunt attacks are more spread out.

  • 1
    I think you've possibly come to the wrong place, or more to the point this question, as it stands, is going to be a poor fit. What I just read is a magnet for Primarily Opinion Based VTCs and I can't see a way of fixing that and getting you the information you desire. As is this is a question of should I A or should I B... with 100 odd different permutations I don't think we can answer that. Secespitus is much better than I am at this side of things though, see what he thinks he can probably see something I don't. – Ash Jul 16 at 17:44
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    @Ash I wouldn't say that this is opinion-based. Answers need to provide reasoning for why a certain combination is better than a different one. These answers can be rated against. The way this question is phrased I would say it's on-topic on WorldBuilding. It would be problematic if it was something like "What would you choose for xyz?", but seems to be objective. About the issue where this question should go: there's a certain degree of overlap between lots of sites, leaving it up to the OP to decide where to post. As long as it's on-topic. The difference is just the focus answers will have – Secespitus Jul 16 at 17:48
  • @Secespitus The issue I see is that there are solid arguments for ignoring all other considerations in favour of a single factor, and those are opinion based arguments. – Ash Jul 16 at 17:55
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    I apologize, I can't quite see how it is opinion based. Perhaps I could better word it if I knew what parts of it were problematic? – Arvex Jul 16 at 18:01
  • Discussions with three people are probably easier in the chat. – Secespitus Jul 16 at 18:08
  • I understand this question as follows: I have found a couple of words related to properties of wood. Could you explain them to me? Am I mistaken? I know this is not literally the question, but to me it sounds like the information you are missing is exactly that. Anyhow, consider asking a question about each parameter individually. Perhaps start with one and see how it goes – Raditz_35 Jul 17 at 16:30
  • This is a reminder about keeping the Sandbox clean: are you still working on this draft? If so, please edit it to show how we may help you further. If not, please edit and shorten it to something like "Not posted: title" and delete the draft to make it easier for others to see which drafts still need help. The current guidelines are that a post is eligible for deletion after 30 days without an edit from the OP and a comment like this one for at least a week. – Secespitus Aug 6 at 11:40
  • I don't have hard numbers here, but here's my take: Crushing strength is almost useless here. You want an extremely high modulus of rupture AND modulus of elasticity (you need it to be able to withstand heavy blows, and elasticity helps with that by reducing the force per area (look up impulse)). The Janka hardness will help increase likelihood a shield will survive a longer time, but less important than the first two. The density of the wood will purely translate to weight--you'll wear your arm out with a heavier shield. – Hosch250 Aug 13 at 14:18
  • FWIW, I think this is a good question as it is, but you might want to find a table of this stuff for woods and ask which specific wood would be best considering this stuff. – Hosch250 Aug 13 at 14:19

What event would cause a huge, dominant nation to adopt the language of a smaller, inferior one?

Inspired by this question. I was thinking about the constructed language I'm building and a group of countries in the history of my world and came up with this question:


I have a small little country (think: about the size of modern day Portugal) bordering (the longest border exactly parallel to) a country the size of modern-day China. The little country is not technologically or magically advanced, has very little education or status, and has few resources and weapons. The larger country is highly technologically advanced and has plentiful weapons and resources, lots of education, fine arts, sciences, and many people there are wealthy, as well as powerful mages.

I have a scenario in which the language of the little country (From now on LC) becomes the official language (the only language spoken, surpassing the original language) of the big country (BC). That is to say, the language of LC completely replaces all other languages of BC, including the native language of BC (English).

The language of LC is highly complex, with a different alphabet, sentence structure, and confusing temporal reference system due to verb conjugations.

The language has no punctuation (instead letters and prefixes or suffixes are added to indicate sentence pausing, stopping, quoting, etc.) and takes even native speakers nearly ten years to be able to speak fluently. Learning (as a child) is simply done by picking up phrases and beginning to understand the highly complex grammar. There are ten different conjugations for verb infinitives (there are a total of 7 different verb infinitives, making a total of 70 different possible conjugations language-wide).

So LC's language isn't easier to learn or speak (or write!). It's not magical and doesn't have any kind of power, takes much more time and effort to learn, is a pain to work with, and isn't really connected to, say, important documents, scholarly findings, ancient works of literature, valuable information, etc, and is viewed at all times with open scorn by BC.

The government of BC is a representative republic with three different law systems, each with an elected council: Law makers, law passers, and enforcers.


What sociological event or trend could have made BC make LC's language the lingua franca? It must adopt both the complex written form and the spoken form. It must become both the official language (what's taught) and the only spoken language (what's actually spoken in the street.) A number of "uneducated souls", like street urchins/criminals/poor people, won't speak much of it, but they have to know enough to get by.

Sandbox Question

I feel (especially with below advice) that this is primarily-opinion based or completely opinion-based. Please provide feedback detaling how I could gently change the question scope or add constraints in order to fix this.

I'd also appreciate any comments on additional information you think I should provide.

Tags I'm planning on using:

  • In the title, it seems you are asking about alternative timeline based on our own world. In body, it looks like it is totally fictional world, so no history to make small change to. Please, remove that discrepancy. – Mołot Jun 4 at 12:25
  • In title, maybe change "change" to "event"? Other than that, I'm still not sure about too-broad/opinion-based. You can write a book on it, and there are not any constrains, and nothing to judge between totally different answer, so there hardly can be better and worse one, and that's usually not good. For sure it is world building. it is not high-concept, as you are not asking people to write your world for you, you want just one specific thing - that's the way it should be. – Mołot Jun 4 at 14:13
  • @Mołot, how would you suggest adding constraints? – FoxElemental Jun 5 at 18:44
  • Those links you mention for hard-science talk about "On the other hand if you are talking about a situation where physics just can't apply...and I am having trouble coming up with one, then sure we can recommend the poster remove the HS tag and maybe add science-based or reality-check instead." and "How far can we stretch it? It depend on the specific question. Philosophy is based on logic, much like mathematics. A specific reasoning can be demonstrated and explained just like an equation." – Secespitus Jun 11 at 8:05
  • Why are you not satisfied with using the language tag like the question that inspired yours? This will confuse lots of people. – Secespitus Jun 11 at 8:05
  • "Language" and "writing system" are two different and orthogonal concepts. Biggia could very well adopt the language of Littlia but not its idiotic writing system. (BTW, speech is always linear; there is no excuse whatsoever for a bidimensional writing system.) You must choose between "official" and "spoken"; for example, there was a time when then mighty Chinese Empire used the language of the Manchus officially. Language shifts are common; the larger and more homogeneous a linguistic community is, the more powerful the reason must be. – AlexP Jun 11 at 10:42
  • Edited. What more, anyone? – FoxElemental Jun 24 at 15:34
  • Sorry you don't want to hear this but in my opinion and experience this is always going to be POB because you're asking about societal change and what makes sense to one person in one society makes no sense at all to another. Even asking about a prime factor in such a change is super awkward. – Ash Jul 3 at 11:35
  • You frame your question in terms of asking for historical & cultural precedents for a large nation adopting the language of its smaller neighbour. Your question in its original form blocks specific ways this could happen. Littlia's status, for example. Usually it is small nations adopting the language of bigger nations. Ask about ways the opposite adoption can happen. For example: if Littlia conquered or colonized Biggia's territory. Or changing Littlia's status from low to extra-high. – a4android Jul 16 at 5:51
  • This is a reminder about keeping the Sandbox clean: are you still working on this draft? If so, please edit it to show how we may further help you. If not, please edit your draft to shorten it to something like "Not posted: title" and delete it. The current guidelines are that a draft is eligible for deletion after 30 days without an edit from the OP and a comment like this one for at least 7 days. – Dubukay Jul 28 at 17:50
  • @Dubukay I modified the Sandbox question and the information slightly, to show what I need help with. Do you have any advice? – FoxElemental Jul 28 at 19:26
  • @FoxElemental Honestly, I’m not 100% sure this is a great place for the question. It sounds more like a human nature/grand strategy politics/random occurrence rather than something we can talk about in an opinion-free matter. I guess I personally would start out investigating why Japanese or English is spoken so widely and then as questions about the likelihood/feasibility of their approaches. – Dubukay Jul 29 at 4:02
  • So you could have it be a holy language. Maybe it is spoken by a specific messianic figure and gains cultural significance. Maybe LC's intermarry into a royal clique, in the same way that Christianity was popularized from top-down in the late Roman empire. Maybe rather than a benign change, this was instituted during an authoritarian interregnum by a despot who worked hard to purge BC culture. (Continued) – user49466 Jul 29 at 21:36
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    @user49466 Please don’t answer questions in the Sandbox. I know it’s tempting, but that’s not what we’re here for. In fact, your response highlights the specific POB problems with this question - you’ve provided two reasonable answers, neither of which can be judged better/worse than the other. The goal here is to give FoxElemental a way to discern between those answers before they get swamped with “spitballs” just like yours on the main site. – Dubukay Jul 30 at 2:25
  • 1
    I kind of agree with Dubukay in the sense that people will probably try to close it as primarily opinion-based. I disagree with those people, since I do see it as a difficult problem and thus there is not a huge realm of possibilites answers can have. Maybe you could add some as-objective-as-possible criteria on how you are going to evaluate answers. – ArtificialSoul Aug 3 at 8:42

How to prevent internal bleeding in a steel-skeletoned being?

In my world there are beings identical to humans aesthetically that have steel bones and 6 times muscle density. However, they are still killable because of 2 reasons:

  1. They can still be cut. However, it is harder due to high density and I will give them tougher skin.

  2. The big problem: one whack from an animal or hammer and they are bleeding on the insides.

So I posit this: Can I change their anatomy to make them immune to or, if that cannot work, resistant to internal bleeding?

  • I don't understand the sentence "9 times muscle density (8 times as strong as humans (stell 2x density of bone))" I think you should reword this and split it into multiple sentences. For example I understand that sentence to be equal to "[...] and they have 9 times the muscle density of an average human. I will furthermore replace their bones with steel, which has 2 times the density of human muscles. Taking the Square-Cube-Law into consideratoin this makes them 8 times stronger than a regular human being." Or something like that. – Secespitus Jul 30 at 19:58
  • Oh damn, wait my logic was bad, nvm. Lemme change it. – P.Lord Jul 30 at 20:01
  • 1
    It sounds like you’re saying that these beings are more susceptible to blunt trauma than regular humans - is that your intent? That the steel skeleton actually makes them more likely to have internal bleeding than a similar impact on a human? – Dubukay Jul 31 at 1:57
  • This is a reminder about keeping the Sandbox clean: are you still working on this draft? If so, please edit it to show how we may further help you. If not, please edit your draft to shorten it to something like "Not posted: title" and delete it. The current guidelines are that a draft is eligible for deletion after 30 days without an edit from the OP and a comment like this one for at least 7 days. – Dubukay Aug 15 at 3:21

Determining precise space time coordinates for time travel

Question: When traveling back in time, how can one achieve a spatial precision of 1 part in a trillion?

Let me start by quoting this article from Scientific American:

Let’s do a quick thought experiment. Imagine you have a nifty time machine and decide to pop one month into the past. Maybe you need to avoid a parking ticket or a particularly debilitating curry, the reason is not important. In a typical story you’ll appear at precisely the same location, just a month earlier. But how on earth does your time machine (or whatever device/spell/weird alien entity you’re using) get you to that unique physical place?

To go back 1 month, and to appear at the same place – your favorite coffee shop, your dining room, your DeLorean trundling down a main street – you must also move a significant amount of physical distance. And you must do this extremely accurately. This is the spatial problem.

Let’s take the Earth’s motion around the Sun. A month of orbit corresponds to moving in an arc of approximately 78 million kilometers. During that same period the entire solar system will have also moved approximately 600 million kilometers around our galaxy, and our entire Local Group of galaxies will have swept through about 1.7 billion kilometers of space relative to the cosmic microwave background. Not only do you need to traverse those kinds of distances, you need to get it correct to within a part in a trillion.

Let's assume a team of scientists have found the way of traveling back and forth in time.

How can they achieve a spatial precision of 1 part in a trillion?


  • Vewy cawefully. Especially difficult since we don't really know all the movements, so even if we hit a precision necessary for our calculations, we still might not hit it. – Hosch250 Aug 9 at 19:15
  • 2
    @Hosch250, this is the sandbox... you should provide hint for improving the question, or not? – L.Dutch Aug 9 at 19:17
  • Interesting draft. What title do you want to use? And I think this is the basic problem that Doctor Who tries to cover with the TARDIS (Time And Relative Dimension In Space). Are you looking for answers like that, which basically revolve around finding a relative point you can use as an anchor? It's also often a good idea to mention the question in a short form in three places: the title, the first paragraph and the last paragraph. You might want to think about starting with the question so that people know whether they want to read the whole question or stop at the first paragraph. – Secespitus Aug 9 at 19:28
  • You might also want to check out some of the questions with similar premise and maybe write how yours is different. For example How can I explain that a time travelling apparatus moves itself through time but appears in the same location? seems to be relevant, though it asks for a generic anchor instead of a certain range of precision if I understand it correctly. – Secespitus Aug 9 at 19:28
  • @L.Dutch Yeah, I should. It looks good to me, though. – Hosch250 Aug 9 at 19:32
  • @Secespitus, I am afraid that Time travel coordinates is very similar. The only difference is just that I specify the needed precision. – L.Dutch Aug 9 at 19:35
  • In that case it might be a good idea to reference that question and some of the answers in your question and state how those do not answer your question. For example: they seem to be mainly qualitative, so you could say something like "[This] answer already answers the theoretical way to do this, but I need an example calculation for 1 part in a trillion. What possibilities exist to use the outlined processs for a quantitative answer with my example?" – Secespitus Aug 9 at 19:49
  • My understanding of these things is limited, but as far as I understand the top answer it's basically a brute-force incremental way that relies on things like GPS and similar technologies. Maybe you could use that as the basis to ask for your precision of 1 part in a trillion? But I feel that this will be a difficult question. The existing answers to this topic basically look to me like "Find some useful technobabble and go for it - you need a relative reference frame anyway as there is no absolute one, so you are srewed in any case". – Secespitus Aug 9 at 19:49
  • I’m a little baffled as to where the “one part in a trillion” comes from. Surely the accuracy required is instead a function of the landing area, both in space and time (so leaving from open air above an open field and being okay with +/- a week is a good idea)? With increasing error margins as the time/space traveled increases? – Dubukay Aug 15 at 3:39
  • @Dubukay, 1 billion km is 1 trillion meter. I assume they want an accuracy of 1 meter. Which is still coarse, I think. I mean, appearing up to your waist in the road is not nice.... – L.Dutch Aug 15 at 5:24
  • @L.Dutch Interesting. So they're just taking the distances traveled in a month and adding them? Which would make time travel back 10 seconds nigh-trivial and travel back 100 years require an accuracy of ppq (parts per quadrillion)? – Dubukay Aug 15 at 6:51
  • @Dubukay, that's my assumption. But I didn't write the article, so I might be wrong – L.Dutch Aug 15 at 6:52
  • @L.Dutch Gotcha. But you're only looking for ppt accuracy and how to make that specifically happen? – Dubukay Aug 15 at 6:54
  • @Dubukay, yes. Though I am still not sure about promoting this to question. – L.Dutch Aug 15 at 7:00

can an STD be used to establish a hive mind?

A parasite exists today which, Although acting on instinct at first, eventually grows more intelligent the further It spreads. It transmits itself by acting in a similar way to an STD, invading a host body and uses it to infect other bodies. This parasite would make the host body infertile, and compel it towards sexual activity with multiple victims. During climax, the parasite passes on a piece of itself into the unsuspecting individual, turning them into a carrier. Over time, it subsumed their mind and compels them to have intercourse with as many people as possible as fast as possible.

Using this method, can a parasite successfully transmit itself into enough people to create a hivemind?

  • And this folks, is how you get a sex-addict apocalypse. If the parasite can access the pheromone-production mechanisms of individuals, master control over the actions for courtship and mating rituals of the host, and amplify the capacity of an individual to be attracted to another species, it could turn the whole world into a red light district within a year or so. – Kyle Zabala Aug 12 at 6:44
  • I think you have already answered your own question by coming up with a way how they spread? Could you perhaps be more precise and state what information you need or what problem needs to be solved? – Raditz_35 Aug 12 at 8:35
  • @Raditz_35 the problem is how would a parasite like this work? There is a type of fungus that can control ants in real life, so I wanted to do the same here. But what mechanism would this creature use to do it and remain undiscovered? – Incognito Aug 12 at 16:15
  • So the question you want to ask is: "How can a parasite can take control over a human?" which is something completely different than what you've asked in your post. If this is your question, please state what apsect you want, for example "How can a parasite can take control over a human biochemically?" or perhaps "Where would the parasite sit in the human body?", but I'm pretty sure I've seen that last one before – Raditz_35 Aug 12 at 17:39


Everything transmits, reflects and absorbs light to some extent. Humans, rocks, the atmosphere, etc.. Everything interacts with any particular wavelength differently.

If you look at a person in sunlight, they cast a shadow as well as reflect certain wavelength back to you while others are absorbed.
Their brown hair absorbs a significant chunk visible light, but reflects a lot of long-wavelength light as well as a uneven mix of other light resulting in the brown colour.

If one could alter matter to no longer reflect any (visible) light, but instead transmit what would under normal circumstances be reflected, what would the visual appearance be?
The light that is being absorbed is still to be absorbed after this alteration.

My guess is that a person altered like this would be invisible, but still cast a shadow.

If we take a more simple example of a piece of red cloth, one could imagine it to be invisible, as it does not reflect any light, but casts a red shadow as all the unreflected red light is now transmitted as if there was nothing in its path.

But the example of a (possibly clothed) human is very difficult, as I am unsure if there are too many layers of different materials that all absorb different wavelength to different extents. So I am unsure whether the shade would likely be grey-black just like a regular shadow or whether it might have some colour if there are certain wavelength that are barely absorbed at all.
I would think that the fleshy inside of a human would mostly reflect red light and thus transmit more of it in this scenario. So would a human cast a slightly red shadow?

How this alteration is to occur is irrelevant to the question. Could be a high-tech sci-fi device as well as magic.
I am well aware that under current scientific understanding this is not possible.
The question is a what-if type of question. Beyond the alteration I mentioned, the laws of physics should not be bent any further.



I am rather certain the question is fine, but I am unsure of what I should put as a title. Originally I wanted to call it something fancy, fantastical, but then I wrote my draft of the question which is rather abstract and thus the originally intended title does not fit well anymore.
But I think solving this issue abstractly is better than a particular scenario.

I am unsure with the tags, too. This is obviously not scientifically possible as electromagnetic waves always interact with matter in a specific way that can not just be changed. So asking this "science-based" feels off. I don't want people to elaborate on magic, but play this what-if-scenario as grounded in science as possible.

  • Isn't this question basically asking what glas looks like? Yes, glas reflects light, but at the right angle, you don't notice that. Tbo, I don't really agree with "the question is fine." Could you perhaps try to rewrite the first couple of paragraphs to make the question more clear? If you want colors btw, you have to explain in what way your people still interact with light. It doesn't really make sense to me right now. I would btw completely cut the paragraph about clothes. – Raditz_35 Aug 13 at 12:13
  • @Raditz_35 It is not like glass. First of all it is not dependend on angle and also it still absorbs a decent fraction of visible light - which glass is specifically designed not to do. Glass is supposed to transmit most of visible light. Of course it does absorb some, but significantly less than any other non-transparent material. The fact that NONE of the light is reflected is what makes the big difference. There is nothing to be seen at the position the object is. – ArtificialSoul Aug 13 at 12:22
  • I agree that there are differences, but they don't seem so big to me. You seem to have a pretty clear picture already, I'm now unsure what you are even asking. I would seriously consider a complete rewrite because as is, the question is confusing to say the least. How the humans interact with light is not sufficiently explained – Raditz_35 Aug 13 at 12:35
  • @Raditz_35 Okay, I'll wait for someone else to comment on it, see what they say and then probably rewrite it. – ArtificialSoul Aug 13 at 12:41
  • I think I get it a bit better now that I read it again. I still think the clothes part should go as it adds nothing but confusion. However, could you be clear on this: Only the light that is absorbed right now by regular humans is being absorbed and not all light that would be absorbed if nothing was reflected? This is such an hypothetical and weird issue which is why I got lost the first time I believe – Raditz_35 Aug 13 at 12:53

Long-term effects of leaving everything you know - the aging issue.

My current ongoing science fiction project has FTL travel that is instantaneous for the ships and their crews, but still, usually, takes years of real-time in the rest of the universe. This is going to have an effect on crews as they are going to lose every contact they make off-ship with every jump they make. I've already assumed that ships crews will therefore be fairly self-contained and have minimal contact with the outside world, but I'm wondering what the long-term effects of such losses might be.

In particular: Would the repeated loss of all of a person's contacts outside their workplace make them age prematurely, psychologically and/or physically?

Answers will need to be grounded in the known science of relationship loss and the long-term effects of repeated trauma and grief. The society is generally much like our own, which means that you're just as likely to find drug abuse, bigotry, and violence in a given population as we might expect to see today.

Starship crews are slightly separated though, partly by a certain mystique and also by an isolationism that cuts both ways. Crews on established circuit routes will usually take 20-30 years to complete a circuit back to a given port, often stopping for only a few weeks at most. Even the people who are still alive will not be the same people they left behind. Crews don't want to get attached to someone they'll likely never see again and people know they're unlikely to ever meet the same crewman twice.


Sandboxing: Just trying to work out the context and content kinks.

  • I am not sure about the title. While I understand the intention behind it the title should already tell people what the question will be about. Maybe something like "What are the psychological effects on my FTL travelling crew when losing their contacts every time they jump?" It should be on-topic, but psychology is always a bit more difficult on this site than maths and physics. I don't know how something like this would fare on a site like Psychology & Neuroscience. – Secespitus Aug 13 at 11:23
  • I rarely see such questions answered successfully, but I don't know why it should be off-topic. However, could you explain if there is the possibility of substance abuse? People in such situations tend to do such things and that would contribute to them aging faster. Cigarettes and some booze have comforted millions of lonely people – Raditz_35 Aug 13 at 11:24
  • @Raditz_35 Thanks I hadn't even thought about that, in general, let alone in relation to this particular question but you're right it could make a big difference. – Ash Aug 13 at 11:26
  • @Raditz_35 Is that clear enough? – Ash Aug 13 at 11:37
  • It's not only people you know, it's everything. Geopolitics for example: after a century-long travel, your country can become a dictatorship, be invaded by another one, decline... The company that send you to this particular planet for profit may have disapeared due to bankrupt... is the question only focused on loss of peoples you know? – Kepotx Aug 13 at 11:58
  • @Kepotx Think a couple of decades between returns to a given port in most cases rather than centuries, very rarely do corporate and governmental structures change. – Ash Aug 13 at 12:10
  • @Ash The length of travel and their frequences can indeed matter, you should probably write it on your question – Kepotx Aug 13 at 12:12
  • To directly answer your question, you have a case of incredibly long and complicated sentence syndrome. I think it is possible to explain the premise in a clearer way – Raditz_35 Aug 13 at 12:15

What could trigger an Inverse Chronological Order experience?

In the movie "Memento", we as the viewer see the movie from what's called Inverse Chronological Order experience, where we see the ending first, and then the subsequent events leading up to the "beginning" of the story (which is not actually the beginning). This is because the character suffers from short term memory loss and cannot form new short term memory, so in order to emulate that, the story is tell using Inverse Chronological Order trope.

Is there any other situation where this situation can be triggered? Just an example I can think of, a brain scanner to find traumatic memory, so the doctor starts from the most recent memory, and then goes further back in the past memory.

Sandboxing: What I'm looking for is the condition or situation that can trigger this, much like this question. But I have a hard time formulating my wording to fit for the community.

  • This question is equivalent to asking : "What premise makes sense to combine with a story/movie told in reverse order?" If it is, please clarify. Or are you looking for someone experiencing life literally like that? In that case, i like your brain idea, the brain is not magic, thus in theory you can trigger someone to experience anything imaginable. I personally would prefer if you excluded all answers that say: make the brain experience that via technology because you already have that option. You just formulated it very narrowly – Raditz_35 Aug 14 at 7:04
  • 1
    I see you have already posted your question on the main site. It seems like you posted it there first. I am not sure what you want from posting it here in the Sandbox. The idea behind the Sandbox is to help people phrase their drafts before posting them or for example if their question is closed and they need help to phrase it in a way to reopen it if you don't want to edit it directly on main. Having two places to work on the same thing is not very useful. And I have no idea how the snowman question is related to this one. – Secespitus Aug 14 at 7:43
  • @Secespitus It's exactly as you think. I posted there first, and then a comment told me to post it here. As I read the sandbox purpose, I think that this is the place to get suggestion to reword my question on the main site. After I reword it here, I will reword my question on the main site. Or delete it and post a new one. The snowman question is asking about "what to do to achieve something". This is the same as that. – Chen Li Yong Aug 14 at 8:47
  • @Raditz_35 Yes, it's equivalent to "What premise makes sense to combine with a story/movie told in reverse order?" If I reworded my question into that, will this be appropriate to post the question on the main site? A comment on my original question says that this is not the place to discuss about storytelling, and refer me to this sandbox. But I see some other questions were talking about something similar to storytelling, so I'm still exploring about what is and what's not about this stack exchange. – Chen Li Yong Aug 14 at 8:51
  • Could you explain the world building context? I think if you can, it might be appropriate eventually. There is a SE for writers if you are just interested in this sort of thing. – Raditz_35 Aug 14 at 8:55
  • There is a little bit of a misunderstanding of the basic idea. The purpose of the Sandbox is to get feedback before you post, not for getting feedback on an open question that is currently on main. But if you want you can use it here, just be aware that only a few people are active in the Sandbox and you might get different or repeated comments on the different versions of your question. – Secespitus Aug 14 at 8:58
  • For me the sentence "Is there any other situation where this situation can be triggered?" is unclear, because it uses the word situation two times and I am not sure what to make of that. The snowman question has a clear goal (snowman should not melt) and asks how to achieve this given a certain starting point (medieval technology with lots of money). Your question asks for the seed of a story (what situation can trigger someone going back-in-time to find something out). I am also not quite sure how this is different from basically every crime story. – Secespitus Aug 14 at 8:59
  • @Raditz_35 ok, I tried to go around the site tour to understand better about the term "world building". I think I will make the question more suitable if I make it more specific like "What kind of technology can make people experience life in backwards?" But this question kinds of limiting the answerers that the answer must be technology, whereas I'm exploring various possibilities and scenarios (or state of the world) where this thing can happen. Actually, I'm trying to look at an established world building from different angle, and then build a new world around that angle. – Chen Li Yong Aug 14 at 9:14
  • @Secespitus sorry, that's probably the influence of my native language slipping out, to use redundant words. Same as what I've explained to Raditz_35, I actually don't want to give the starting point because I want the starting point can come from anywhere. I probably can give the starting point like "In 1000 years in the future, what kind of technology can make people experience life in backwards?" But that will severely limiting the domain of answer, while I'm expecting answers as out of the box as possible. – Chen Li Yong Aug 14 at 9:28
  • Here is the thing: You can write any story like that. Some are more suitable than others, but this sort of thing was really popular a while ago and people did this with everything. Even Seinfeld has a backwards episode. I think your question could fit, but you have to make absolutely clear what you want the answers to be and how it relates to world building – Raditz_35 Aug 14 at 9:38
  • If you are only looking for ideas and basically brainstorming then WorldBuilding.SE may not be the site for you. At least not the main site. Your question is primarily opinion-based if every reasonable answer is exactly equally valid without any criteria that would make one answer somewhat objectively better than another one. That means it will be closed as opinion-based, because ultimately you are looking for a pool of ideas where you can choose which one sounds the most cool to you. StackExchange is built around clear question with clear best answers. Worldbuilding Chat is more open-ended, but main not. – Secespitus Aug 14 at 10:23
  • Secespitus and Raditz have given you some good feedback already, but one surefire way to avoid a lot of POB votes is to pick your best guess and reality-check it. I think you’ve got a good start with the doctor idea and that could serve as the nucleus of a question in which you check it’s plausibility. Sadly, idea-generation questions here are generally off-topic. – Dubukay 23 hours ago
  • 1
    @Dubukay thanks! I'll try to look for answers elsewhere. But in the meantime, the sole answer provided in my original question actually was sufficient. – Chen Li Yong 8 hours ago
  • @ChenLiYong Great to hear! If you don’t need this draft anymore, please shorten it to something like “Not posted: title” and delete it to keep the Sandbox clean. – Dubukay 1 hour ago

How can I keep myself from going crazy while drifting through space?

I was a nuclear physicist working in a spaceborne laboratory, in orbit a far orbit around the sun, near Pluto. We were working on developing specialized radioactive compounds and chemicals for use in various top-secret experiments, when one of the scientists in a neighboring laboratory accidentally punctured a tank full of a certain explosive solvent we were using. On recognizing that I would surely die, with nothing to lose, I injected myself with every single substance I could find in my section of the laboratory.

Our safety systems failed, and the whole space station exploded violently. I was hurled into space. My space suit has holes burned into it, and I was hit with a wide variety of shrapnel, but I have no marks or injuries on me, and I'm tolerating the vacuum of space comfortably. I'm immortal.

As it happens, the laboratory fanny-pack I was wearing remains in tact. It contains this solar powered handheld computer, a few small tools (screw drivers, etc), some string, some aluminum foil, and a flask full of whisky which I smuggled onto the station

The handheld computer has the ability to transmit simple ASCII messages one-way to earth, and some software for calculating orbits. I've figured out that I'm on a trajectory which will eventually escape the solar system. There's no chance of rescue, as far as I can tell, and I expect to spend the next trillion years or so drifting through space.

How can I best make use of my time drifting through space, in order to invoke the least amount of psychological harm to myself? I'd like to avoid going crazy if possible, but I know that I have a very long time to wait.


This is for a character in a story I'm working on. The character enters the story this way: Eventually he lands on a planet very far away in space. His computer breaks in the process of landing, and during the time it takes for earth to develop the technology to reach him, they forget about him. Over the course of a very, very long time, he single-handedly fosters the development of the planet. He eventually produces a beacon, which is detected by far-future humanoid space explorers, who bring him back to society where he interacts with the main group of characters in the story.

A favored answer will include, in addition to some time-wasting ideas, information about the psychological effects that prolonged participation in various activities will have. Is the outcome always the same for him, psychologically? I'm looking for his mental status at the time when he reaches the planet. Ideas which involve meditating to transcend the physical body are ok, too, as long as they are fleshed out a little bit toward how it affects the development of this character's personality, whether the meditation succeeds or fails.


  • ASCII is normally written in all-caps as it's an abbreviation. I'd also link to the corresponding Wikipedia article for those not familiar with it. Are the notes Sandbox notes or do you intend to keep them in the question? I think they should be kept. Especially the last paragraph is important as it details what answers should provide, but the first doesn't seem to add too much to the question, which might make people skip the rest once they reached the bolded question. A little warning: psychology questions tend to be more difficult on WorldBuilding than for example physics. What about tags? – Secespitus Aug 15 at 20:35
  • You might also be interested in New stages of human psychology if we live forever? and How long is the subjective experience of eternity? (both of which are closed as primarily opinion-based) – Secespitus Aug 15 at 20:47
  • @Secespitus Good feedback, thanks! Also, helpful links. Since both of those linked questions were closed, do you think my question would be better if I simplified it down to "ideas for wasting time while drifting through space", and then posted separate questions to the Psychology and Neuroscience SE for the psychological impact? – boxcartenant Aug 16 at 1:39
  • Asking for ideas is not a good idea. It would be a good idea for the Factory Floor, WorldBuilding.SE's main chat room, but it's discouraged on the main site as every somewhat reasonable idea is exactly equally valid - which means the question is primarily opinion-based. It would be up to you which ideas you think are "cool" and which are not. Asking about psychological effects of long-term loneliness and how to combat it should be on-topic (We don't have data about this time range, but that should be extrapolated), ideas are not. – Secespitus Aug 16 at 7:33
  • I agree with Secespitus’s last comment. Asking for idea generation will definitely get your question closed, while focusing exclusively on the psychological effects of doing nothing would certainly be on-topic. Perhaps pick one of your time-wasting ideas and reality-check how feasible it is and how long it could reasonably keep you occupied? – Dubukay 23 hours ago

Making the 'Master Swordsman' fantasy realistic?

The idea of a truly masterful swordsman capable of taking on dozens of average swordsmen by himself (sometimes even above average!) is a pretty common depiction in fantasy media.

A recent example I can think of is Barristan Selmy from A Song of Ice and Fire, who supposedly could have taken on a room full of elite swordsmen by himself.

Realistically, though, such a thing is certainly not possible.

Clearly, some changes would need to be made to human physiology in order for the Medieval world to resemble our own while still being sufficiently different enough to enable this concept.

I propose two changes:

  • Make 'reaction time' a muscle that can be trained just like any other
  • The rate at which muscles expand while growing stronger is halved (more compact muscles, less energy requirements, but still stronger)

Would the realistic results of these two changes enable classical Medieval combat to more closely resemble the 'Master Swordsman' fantasy exemplified earlier?

This is my first post to the Sandbox, so I'm not sure if I'm doing this right. I've asked questions before that have gotten closed, so I figured maybe I should see what you think here, first.

  • Take the room-full on--one at a time... P.S. Only so many can reach you at a time. You are using the sandbox correctly, FYI. – Hosch250 Aug 14 at 17:41
  • Hi, this is exactly what the Sandbox is intended for. Currently your draft looks a bit opinion-based: what kind of change are you looking for? Something like the Matrix allowing you to "download" unlimited knowledge compared to normal people? Something "physical" like allowing people to live forever and therefore train one skill for centuries? Something like "magic for some individuals"? Something "ethical" that only allows people to fight one-on-one? You have a lot of possibilities and most fiction is simply glossing over this, so currently it's basically up to what you think sounds cool. – Secespitus Aug 14 at 20:34
  • @Sescespitus Thank you for your help! I added some more details, specifying what specific genre I was looking for, does that help? – Onyz Aug 15 at 11:15
  • A little tip: you should try to use the autocomplete function. I didn't get any notification because there is an extra "s" before the "c" in your last comment and just saw this because I was going through the Sandbox ;) Are you looking for something like a scientifically semi-valid super soldier? Your question might be a bit too broad. – Secespitus Aug 15 at 20:46
  • @Secespitus Let me see if I can narrow it down to a particular possibility, and see if that helps. – Onyz Aug 16 at 11:28

Ringstadt: Getting sulphur into my water

You sure lad? For some of you folks normal beer is already an acquired taste, but this... this beer definitely is. You understand that this stuff is brewed with water from the devil's choke? You know, that vile spring right behind the abbey?

Last words Hans M'wambe, Private 1st Class, recalls before getting booted out of the Lifted Spirits Pub for distributing the contents of his stomach all over the Bartender.

This question is a spin-off to this question about the topography in the below map. Please refer to it for general questions or observations about the map & area.

This spin-off is about the peat bog in the I3 to J5 area (the square denoted by these corners), and the spring at I5; regarding the process 'enriching' the spring-water with sulphur up to a degree where it needs to be filtered to be consumable.


From reading this article on sulphur in peat bogs and other lay-man's research, I understand that peat bogs are areas where sulphur is filtered from the surroundings and deposited.

I imagine that precipitation collects from the hills around and drains into the bog, from which it sips into lower strata where it meets rock and gets eventually pushed out of the cliff-side in I5.

My hopes are, that the water, when seeping through the bog, can be 'enriched' with sulphur by some sort of process, but I do not understand enough about biology to know of any such process - or if this is even impossible.

[SANDBOX NOTE: The below map will be adjusted and replaced once the previous question has enough views and/or an answer with 10+ votes]

Ringstadt topological map

 brown                ->  topological lines, 10 meters each
 light blue -line-    ->  streams, rivers
 light blue -shaded-  ->  bodies of water
 turquoise            ->  peat bog
 olive                ->  reed marshes

Each grid-cell is 400m by 400m.

Q: Can my peat-bog-spring-idea result in water enriched with sulphur to a degree that it needs to be filtered?

A good answer should at least address the following topics:

  • What circumstances are necessary for this to happen?
  • If this cannot work, what alternative process could provide the desired result?

In addition it would be amazing if an answer could delve into the science:

  • How does the process of 'enriching' the water work?
  • What compounds are involved?

Sandbox Questions

This question is designed as a follow-up in a series of questions accompanying me during the process of designing and mapping out my fictional city 'Ringstadt' (fancy German title based on the fact that the city has a circular wall with a 2 mile diameter).

This question will be one of a bunch exploring different details of the topographical map I drew in the series' primer. The features being explored in this and other questions have originally been decided as being distracting from the main problem and thus been marked as spin-offs.

  • Information I would like to get from asking this question:

    • Does my proposed process achieve the desired result?
    • Is there any viable alternative to achieve my desire?
    • BONUS: How does the process work under the hood?
  • Standard Sandbox Stuff:

    • Is this question feasible for the WB format?
    • Any better ideas for the title?
    • Any better ideas regarding the tags?
    • Is the partitioning of the question contents making it easier or harder to read the question?

Ringstadt: Which of my streams are spring-fed, and why?

Aside from that ghastly thing behind the abbey, yeah. No need for iodine in this city, unless you feel like drinking from the harbour basin that is.. haha!

Quartermaster of the Foreign Casern to Hans M'wambe, Lance Corporal Aspirant Mechanic, after the latter proclaiming disbelief about people drinking directly from wells on the streets.

This question is a spin-off to this question about the topography in the below map. Please refer to it for general questions or observations about the map & area.

This spin-off is about determining which of the streams marked on below map could & should be spring-fed. Or, alternatively, which of the streams can absolutely not be originating from a spring.

Streams & Springs:

From my reading up on springs on wikipedia I understand that I can have a spring at I5, fed by the seepage of the peat bog further north and above it.

But how would springs further up work, e.g. some of those feeding into the upper lake, or the into the river? Do I need to have lakes/ponds further up that have no direct outflow or are there also other ways?

[SANDBOX NOTE: The below map will be adjusted and replaced once the previous question has enough views and/or an answer with 10+ votes]

Ringstadt topological map

 brown                ->  topological lines, 10 meters each
 light blue -line-    ->  streams, rivers
 light blue -shaded-  ->  bodies of water
 turquoise            ->  peat bog
 olive                ->  reed marshes

Each grid-cell is 400m by 400m.

Q: Which of my streams are spring-fed, and why?

Answers should go about either explain which streams would be springs, and why or go about the inverse and explain which streams would not be spring-fed, and why.

A good answer will, in either case, at least address the following topics:

  • What kinds of springs are feasibly encountered in this mapped area?
  • Are there any parts of the map that are obviously missing streams?

Sandbox Questions

This question is designed as a follow-up in a series of questions accompanying me during the process of designing and mapping out my fictional city 'Ringstadt' (fancy German title based on the fact that the city has a circular wall with a 2 mile diameter).

This question will be one of a bunch exploring different details of the topographical map I drew in the series' primer. The features being explored in this and other questions have originally been decided as being distracting from the main problem and thus been marked as spin-offs.

  • Information I would like to get from asking this question:

    • Which of the streams I marked on the map could/should be fed by springs?
    • What kind of spring would be best for each of these and why?
  • Standard Sandbox Stuff:

    • Is this question feasible for the WB format?
    • Any better ideas for the title?
    • Any better ideas regarding the tags?
    • Is the partitioning of the question contents making it easier or harder to read the question?
  • To make an informed judgement on this we're going to need to have a look at the prevailing weather, springs are only required in rainshadows, elsewhere it's "it could a spring but doesn't have to be." – Ash 21 hours ago
  • @Ash that is a very good point; this question is now likely to remain in the sandbox for a month; unless I manage to find very easy to comprehend material about weather patterns – dot_Sp0T 21 hours ago
  • Also we need to know the underlying geology to understand where, if at all, springs are possible, springs need permeable material (rock, sand, or gravel) for the water to flow through and usually impermeable layers as well. – Ash 21 hours ago

Would planets be cubic in my "cuboverse"?


The main idea behind the "cuboverse" is that spacetime distances are measured by (something close to) the sup norm or infinity norm. Under this norm, spheres (the set of points at a fixed distance from an origin) are the same as cubes, hence the name.

Other features that I have been able to derive from this are:

  • Geodesics are straight lines like in our world, but

  • Objects can basically only move at a certain constant speed, and only in one of eight special directions, $(\pm 1, \pm 1, \pm 1)$ in Cartesian coordinates.

  • There is an attractive force of "gravity", and a second cohesive force that allows primordial material to form big planet-like bodies of liquid.

My question is:

Would planets be cubic in this universe? If not, what shape would they attain (octahedra, ordinary spheres, unstable, something else)?

I would prefer answers based on physical reasoning, taking into account the relevant changes to real-world physics (see the details section below). Any other plausible modifications to the physics are allowed if needed for the answer, but not magic/handwaving.

Background [Sandbox note: should I remove this?]

I recently discovered the science fiction writer Greg Egan. Many of his novels like Diaspora, the Orthogonal series and Dichronauts share the idea of changing one or more fundamental things about our world's physics (the number of dimensions, the metric signature of these dimensions, changes to particle physics etc.) and exploring the consequences of that change. The author keeps some science notes online relating to these works, and after reading them I got inspired to attempt to build one such world myself.

The cuboverse I imagined consists of big cubic planets made of liquid (similar to water), one of them inhabited by a small intelligent species of eight-spiked "sea urchins", along with some other eel-like and carpet-like sentient creatures, all of them living near the surface. There are no stars in this world, so the necessary heat comes from the planet itself. I have already thought of a method of propulsion for the sea urchins and some rough details about their society. I still haven't developed the chemistry and particle physics, and I also have some questions about the biology, but first of all I would like to know whether the setting I imagined (specifically the shape of the planets and their stability) is realistic in the context of this modified physics.


As a warning, I'm not at all experienced in exploring alternate world physics, it's my first time doing this, so some of the things I derived below could be wrong. Anyways, my basic idea is to change the Minkowski metric

$$ds = (-c^2 dt^2 + dx^2 + dy^2 + dz^2)^{1/2}$$

to a $\lambda$-norm

$$ds = (-c^\lambda |dt|^\lambda + |dx|^\lambda + |dy|^\lambda + |dz|^\lambda)^{1/\lambda},$$

where $\lambda$ is a very big number (I decided not to choose the sup norm itself $\lambda \to \infty$ because that would make geodesics non-unique). According to this, with this norm spacetime seemingly becomes a kind of Lorentzian analog of a Finsler geometry. We can calculate geodesics (which turn out to be straight lines) and define a four-momentum vector for point particles as usual.

Taking the nonrelativistic limit and choosing appropiate units for the energy (I can provide details if needed), we arrive at equations for the momentum $p_i = m |v_i|^{\lambda-1} \operatorname{sign}(v_i)$, rest energy $E_{\mathrm{rest}} = mc^\lambda$ and kinetic energy $E_{\mathrm{kin}} = \dfrac{m(|v_x|^\lambda+|v_y|^\lambda+|v_z|^\lambda)}{\lambda}$.

Newton's second law $\mathbf{F} = \dfrac{d\mathbf{p}}{dt}$ still holds, so heuristically, for a generic set of particles at generic positions under the action of generic forces, the probability that the momenta have one or more components nearly equal to zero will be very small. Since $\lambda$ is very big, the components of the velocity vector will generically be $$v_i = \pm \left\vert\dfrac{p_i}{m}\right\vert^{1/(\lambda-1)} \approx \pm \left\vert\dfrac{p_i}{m}\right\vert^0 = \pm 1,$$ as I claimed in the summary. This implies, among other things, that it is virtually impossible for any object to stay still: its velocity will always be one of the eight possible vectors pictured below (which one depends on which octant the momentum vector lies).

Eight possible velocity vectors in the "cuboverse"

For gravity, the most reasonable thing would be to work with a generalized gravitational potential $V = \dfrac{Gm_1 m_2}{\lVert\mathbf{r}\rVert_\lambda}$, where $\lVert\mathbf{r}\rVert_\lambda = (|r_x|^\lambda + |r_y|^\lambda + |r_z|^\lambda)^{1/\lambda}$ is the sup norm distance between two particles of masses $m_1$ and $m_2$. I managed to make some calculations but the orbits look too funky, so I decided to get rid of stars and planetary systems completely, having instead a single kind of astronomical body. If planets are cubic (that's my question!), I believe the gravity near the surface would be constant.

Since it is extremely easy to move a stationary object by applying a very small force, every big structure would become unstable under gravity and contact forces alone, so I decided to have a secondary Van der Waals-like cohesive force that sticks particles of primordial matter together, while still allowing for some free fluid-like motion. I am not really sure how this force will look like since the chemistry isn't yet developed, so for the moment I'm forced to work with this rough description of how I want it to behave.

For the moment, as a starting point I'm assuming the primordial matter consists of small hard particles, either ordinary spheres or cubes, and studying the collapse of a cloud of this material under gravity and a perfectly inelastic cohesive force (these assumptions can be changed if needed for the answer). At this point the analysis becomes more difficult, and I've been unable to find whether the planets are cubes or not. Based on the form of the gravitational potential, I would expect a "yes" answer, but the weird restrictions on the velocity make me doubt. Also, I'm not completely sure that a cohesive force will fully solve the instability problem. Perhaps a simulation would help at this point, but I don't currently have access to simulation software, and anyways I have a feeling that the answer is easy and I'm just overlooking something.

Sandbox Questions

-Is this question appropiate for this site?

The question is kind of in the limbo because it's too otherwordly to be posted in Physics Stack Exchange. I was doubting whether to post it here or to post it in Math Stack Exchange as a mathematical physics question (stripped of all context). I'm leaning towards posting it here because many aspects of the physics are not rigorously fleshed out yet.

-Is the question clear/understandable?

The question is meant to be directed at users with some knowledge of physics/astronomy, but I don't know if that's an ok thing to do here. Perhaps I should avoid some of the technical jargon and/or reword the question in a way that more people can understand and answer. I included a summary but I don't know if that's enough. Also I'm not a native English speaker so I may have made some spelling/grammar mistakes.

-Is the question too specific or too broad? Did I provide too many unnecessary details, or not enough essential details?

My worry is that I provided too many details, making the question too long.

-Did I make any bad mistakes (the kind that would make the question trivial or stupid)?

-Are the tags and the title appropriate?

Thanks for your help.

  • Hi pregunton, and welcome to Worldbuilding! It’s awesome that you found our sandbox because I think this question is an excellent fit, although I don’t understand a lot of the math you use or what even the sup norm really is lol. Don’t worry, we’ve got some veteran astrophysicists here who will probably love to take some time on your question. – Dubukay yesterday
  • I have two specific comments - one, I think your equation for a generalized gravitational potential should have a superscript where it currently has a subscript? Second, I think this is begging for the hard-science tag. What other ones are you thinking about using? – Dubukay yesterday
  • @Dubukay Hi, and thanks for the warm welcome! :) About the potential, the notation $\lVert \mathbf{r} \rVert_\lambda$ was meant to be an abbreviation of $(r_x^\lambda + r_y^\lambda + r_z^\lambda)^{1/\lambda}.$ I took it from wikipedia, but I see now that it can potentially be confusing, I'll add a sentence explaining it (also I just noticed I missed the masses in the formula). – pregunton yesterday
  • @Dubukay About the tags, I had thought of using reality-check, alien-geometry, physics and nonspherical-worlds. From reading the tag description, I mistakenly understood that hard-science was only for real world settings, since it requires the use of empirical evidence or scientific papers, but now I'm taking a look at some of the questions and it seems there are some that deal with modifications of physics like mine. Do you think I should add that tag instead of the physics tag? – pregunton yesterday
  • Cool! Thanks for expanding that, it helps (me) a lot. I think your tags are very apt, but I’d swap the reality-check for hard-science. I think of reality-check as a vaguer kinda sciencey kinda not tag, while hard-science makes it clear that you’re looking for specifically the science ones. I do think I’d include physics though! – Dubukay yesterday
  • @Dubukay Thanks again for your help, you convinced me to replace the reality-check tag by hard-science. Now I guess I should wait some more days before deeming the question ready, in case anyone else has more comments or concerns. – pregunton 16 hours ago
  • sure! That’s what we’re here for :) The Sandbox is currently a little full (a good thing!) so I might leave it up a week or more to get some really good feedback. – Dubukay 16 hours ago

Ringstadt: Can my mountains be what I need them to?

When the old mining town was founded, nobody did think of this ever growing into much more than a coal-mining town. The deposits of iron-ore, aside from the already developed peat bog to the north, driving the tools & weapons industries this city is now thriving from, have originally been estimated to be much smaller in size - and deemed not worthy of exploitation..

Introductory course to the History & Sociology of the tri-region area, Ringstadt Militaric University.

This question is a spin-off to this question about the topography in the below map. Please refer to it for general questions or observations about the map & area.

This spin-off is about understanding & determining the make up of the mountains to the north of the map. For future story-purposes the mountains/rock will have to fulfill certain properties, this is about finding out if my goals for them are possible or if I need to rethink this part.

Desired Properties:

For the purpose of developing an eventual city in this area, I was planning to have initial mines along the ridge from D2 to F3 (later expanding towards H4) producing coal from strata mostly parallel to adjacent ground-level.

Eventually I wanted expansion and further prospecting to reveal massive depots of iron and preferably some other ores/minerals as well (maybe copper?) in the deeper strata below the coal. Coal being carbonized organics, I imagined that the coal layer(s) could have been folded on top of the ore deposits by glacial movement or similar.

In order to get access to lower strata and deposits I imagined some eventual open-pit mining in the F2 area, the resulting waste-rock being used as building materials (if I can have sandstone, granite or other building rock there) and to raise embankments in the C2 to C5 area, creating a protected harbour.

For story & fanciness purposes I would love to have big tunnels leading into the mountains, and massive underground caverns that are left-overs from the mining process (so I can fill them with secret military installations, or simply storage, or what not).

[SANDBOX NOTE: The below map will be adjusted and replaced once the previous question has enough views and/or an answer with 10+ votes]

Ringstadt topological map

 brown                ->  topological lines, 10 meters each
 light blue -line-    ->  streams, rivers
 light blue -shaded-  ->  bodies of water
 turquoise            ->  peat bog
 olive                ->  reed marshes

Each grid-cell is 400m by 400m.

Q: Can the above described desired properties be realistically met by the rock and soil in this area Can my mountains be what I need them to?

A good answer should at least address the following topics:

  • Can I have the resources I in the described area?
    • Can I have the upper layer of coal-seams?
    • Can I have the massive iron deposits?
    • Can I have the supplemental Copper (or other useful ore) deposit(s)?
  • If this cannot work, why - what stands in the way of it?

In addition it would be amazing if answers that explain why this cannot happen, to include a section proposing alternative situations of resources that come close/to a similar result as what I am describing in the above prose.

  • Please ignore the resources available in the peat-bog; I know there will be bog-iron and it will play a significant part in the earlier development of the region. Same goes for the clay and gravel available through the reed-marshes and river-deposits.

Sandbox Questions

This question is designed as a follow-up in a series of questions accompanying me during the process of designing and mapping out my fictional city 'Ringstadt' (fancy German title based on the fact that the city has a circular wall with a 2 mile diameter).

This question will be one of a bunch exploring different details of the topographical map I drew in the series' primer. The features being explored in this and other questions have originally been decided as being distracting from the main problem and thus been marked as spin-offs.

  • Information I would like to get from asking this question:

    • Can I have this?
    • How does the dirt and rocks and strata of them look?
    • Why can't I have this?
    • What can I have instead that is close to this?
  • Standard Sandbox Stuff:

    • Is this question feasible for the WB format?
    • Any better ideas for the title?
    • Any better ideas regarding the tags?
    • Is the partitioning of the question contents making it easier or harder to read the question?
  • Unless you change the current biomes you'll get bog iron, you might want to point out that you already know about it or everyone will tell you all about it. – Ash 21 hours ago
  • @Ash I did not know about bog iron. I will add a paragraph pretending that I did and secretly thank you here – dot_Sp0T 21 hours ago
  • All good it's one of those odd resources that history has largely forgotten. – Ash 21 hours ago
  • If you remember ping me on chat when you post these, I don't want to miss any of them if I can avoid it. – Ash 20 hours ago
  • @Ash as long as this comment stays I will remember – dot_Sp0T 20 hours ago

Posted Question: What is a usable formula for determining the necessary strength of a planet’s magnetic field for it to be habitable?

  • 1
    This could also be on topic for something like Astronomy.SE: they have that nice astrochemistry tag :) – JavaScriptCoder Aug 14 at 14:55
  • 1
    I'd change it to ask about the generic way to figure this out yourself so that answers give you some formula that lets you plug in some numbers from a certain star and get your result that way. Then add something like "As an example answers should use [Super Special Star X]" to get some example numbers and calculations. That makes it easily applicable to a wide audience, gives you a specific example and an easy way to get the rest of the numbers. It's also likely people will just add a handful of numbers for other star classes. A few links to Wikipedia, especially for the star, would be nice. – Secespitus Aug 14 at 14:57
  • @JavaScriptCoder Does SE allow duplicate questions on different sites? I’d rather ask here since I’m more familiar with our rules, but asking on Astronomy would probably yield better results... Hmmm... – Pleiades Aug 14 at 18:36
  • 1
    I think it’s probably frowned upon. I’m not sure, haven’t done it before, but ask one of the more experienced users like @Secespitus. If stuff goes wrong on Astronomy you could always ask around in Astronomy.SE chat. – JavaScriptCoder Aug 14 at 18:39
  • @Secespitus I wasn’t sure if that was too broad or not. Having given this question some though, it occurred to me that planetary size AND star size would be factors, so asking for a formula probably would be better. The only issue there for me though is figuring out which variables to include and which to ignore lol. I might reword this when I have time later and have two versions of this and decide which one works better. – Pleiades Aug 14 at 18:39
  • (Also, thank you for responding to quite literally every question I draft here. You’re a godsend to this site, @Secespitus ) – Pleiades Aug 14 at 18:41
  • 1
    You shouldn't cross-post on different sites of the network. It is frowned upon because it basically shows that you didn't think carefully about the scope of the sites and the goal of your question. There are certainly cases where a question is off-topic on one site and on-topic on another one - that's why we have migrations after all - but in general there are quite a few differences between sites and it's a good idea to think about whether you want a worldbuilders perspective that might for example give you some "That's not fun for a story, use this instead" additional info. CC: @JavaScript – Secespitus Aug 14 at 20:41
  • 1
    If you are not sure which factors are relevant that is fine, too. Just state in your question that your researched showed that planetary size and star size should be relevant, but you are not sure if there is more to account for. If you go with the specific star example people can just add the needed information - they have a concrete example after all - so there is no information missing, preventing "unclear what you are asking" votes. Thanks for the compliment, I am trying my best to help where I can :D – Secespitus Aug 14 at 20:41
  • 1
    When you have two question drafts in one post I'd add something to visually differentiate them. Otherwise it looks like one draft with one question because that is what most people do. People who have read your post might otherwise skip over the first part they remember to have read already and go to the second part, only to be a bit confused about reading the same start. I'd still combine them and say "I am looking for a formula so that I can check out the numbers for different star classes and would appreciate an example calculation with [this specific star]". – Secespitus Aug 15 at 20:38
  • @Secespitus Does this draft look better? – Pleiades 11 hours ago
  • 1
    If you are fine with educated guesses science-based is better, especially because people will also expect the same kind of scientific rigor from you as the querent that you expect from people answering a hard-science question. I think it's fine. Good luck! – Secespitus 7 hours ago

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