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Population of the Imperium

Real-world explanation (in case this isn’t obvious): different tools/rules being used to generate the sectors over time, and a lack of ability/effort/determination to identify and correct the inconsistency.

In-world: dunno. Maybe many of the naval bases in the rim - which would have been claimed by the rebelling Sollies - were destroyed during the Rim War as the Imperial fleets advanced, and only those along the de facto border following the armistice have been a priority to re-establish.

For me it isn't obvious, somewhere in the back of my mind I had been presuming that for Imperial sectors, at least, they had all been generated all at once using the same ruleset so statistical anomalies probably had a design purpose behind them. I don't know the history of how the canon maps came about. I need to take a closer look at the sector metadata at some point.

But I was mostly looking for in-world explanations, and if the solomani rim is filled with burnt out husks of military bases scattered across dozens of worlds.
 
Are the populations of those worlds in the UWP representative of permanent civilian population or are military also counted? I noticed that some of the world named Depot have fairly small populations, like Depot/Corr and Depot 2/Delp, at 10,000 each (given that today's pentagon on earth has more than 25,000 employees, 10,000 seems small for a giant military base)

IRL Guam has around 7000 active military with an additional 5000 family members, from what I've been able to determine. I'll admit that my confidence level in those numbers is not super high but I think they are in the ballpark at least (and given current tensions in the Pacific Guam is not an inconsequential naval base).

My guess is that those are -not- 'giant military bases'. After all, when it was initially created Fort Wainwright only housed about 50 soldiers (yes, it has since expanded to around 7700 soldiers, but my point is that sometimes a government will feel that there needs to be some sort of presence in a location, even if it is a pretty small presence). Yes, they are bases and they are about the only thing around, hence the naming of the place as 'Depot', but they are not what most people in the Imperium would view as 'large'.
 
IRL Guam has around 7000 active military with an additional 5000 family members, from what I've been able to determine. I'll admit that my confidence level in those numbers is not super high but I think they are in the ballpark at least (and given current tensions in the Pacific Guam is not an inconsequential naval base).

My guess is that those are -not- 'giant military bases'. After all, when it was initially created Fort Wainwright only housed about 50 soldiers (yes, it has since expanded to around 7700 soldiers, but my point is that sometimes a government will feel that there needs to be some sort of presence in a location, even if it is a pretty small presence). Yes, they are bases and they are about the only thing around, hence the naming of the place as 'Depot', but they are not what most people in the Imperium would view as 'large'.

The US has about 800 military bases for a population of about 322 million people, one base for roughly every 400,000 people. Scaling that up to the imperium (population 18,049,041,349,210, give or take) we would expect to see just under 45 million military bases, but instead there are 1377 naval bases and 1465 scout bases for a total of 2842 bases: that's a factor of 15759, if we presume that the imperial military scales similar to population that the US military does. I would argue that basing is more important in the Imperium given how long it takes to move soldiers around vs on earth, but since this is all speculation let's leave it at that.

So with a factor of 15759, we could claim that Guam, in relative terms in the Imperium, would have about 121 million personnel.

It is difficult to determine if military size and basing requirements would scale with population though.
 
Are the populations of those worlds in the UWP representative of permanent civilian population or are military also counted? I noticed that some of the world named Depot have fairly small populations, like Depot/Corr and Depot 2/Delp, at 10,000 each (given that today's pentagon on earth has more than 25,000 employees, 10,000 seems small for a giant military base)

Good question.

Depots turn up in the reference material a bit, they're listed as entire systems devoted to the Navy - which could be a lot of people. The only real in-depth discussion I've seen was an adventure in DGP's MegaTraveller Journal, and again it waxed poetic on how many people were there in its heyday.

I guess it depends on how you decide you want it counted - does the current US Census list serving military personnel as a separate category, or under the state the people declare as their permanent residence?

Using that as an example, there could very well be ten thousand 'natives of Depot/Corridor' that run farms and ranches and fishing boats and sell to the Navy, and only those people get counted there, while the other fifty million officers and ratings of the Navy that make the Depot work get counted as temporary postings, so not counted there.
 
For me it isn't obvious, somewhere in the back of my mind I had been presuming that for Imperial sectors, at least, they had all been generated all at once using the same ruleset so statistical anomalies probably had a design purpose behind them. I don't know the history of how the canon maps came about. I need to take a closer look at the sector metadata at some point.

https://travellermap.com/doc/credits may be useful. It's organized semi-chronologicaly, at least at first.

Short version: Spinward Marches and Solomani Rim were generated by hand by GDW. A few other sectors were developed by licensees (Old Expanses, Trojan Reach, Reavers Deep, etc). Then the rest of the Imperium was generated using code (original code and data presumed lost) for Atlas of the Imperium. The data was seemingly handed off to DGP, which massaged it a bit and eventually released it online, although it doesn't exactly match what was in the Atlas - unsure how/why the errors crept in. Various individuals made tweaks to the data over time, and attempted to reconcile it with later publications. Eventually the recent "T5SS" process took a snapshot of what data was out there, fixed some errors, incorporated some feedback, did some amount of updating.
 
IRL Guam has around 7000 active military with an additional 5000 family members, from what I've been able to determine. I'll admit that my confidence level in those numbers is not super high but I think they are in the ballpark at least (and given current tensions in the Pacific Guam is not an inconsequential naval base).

My guess is that those are -not- 'giant military bases'. After all, when it was initially created Fort Wainwright only housed about 50 soldiers (yes, it has since expanded to around 7700 soldiers, but my point is that sometimes a government will feel that there needs to be some sort of presence in a location, even if it is a pretty small presence). Yes, they are bases and they are about the only thing around, hence the naming of the place as 'Depot', but they are not what most people in the Imperium would view as 'large'.
Some Depots have such a small population because the sector duke was worried they might tip over and capsize....
https://www.youtube.com/watch?v=cesSRfXqS1Q
 
The US has about 800 military bases for a population of about 322 million people, one base for roughly every 400,000 people. Scaling that up to the imperium (population 18,049,041,349,210, give or take) we would expect to see just under 45 million military bases, but instead there are 1377 naval bases and 1465 scout bases for a total of 2842 bases: that's a factor of 15759, if we presume that the imperial military scales similar to population that the US military does. I would argue that basing is more important in the Imperium given how long it takes to move soldiers around vs on earth, but since this is all speculation let's leave it at that.

So with a factor of 15759, we could claim that Guam, in relative terms in the Imperium, would have about 121 million personnel.

It is difficult to determine if military size and basing requirements would scale with population though.

I really wouldn't use the number of military bases America has and compare them to the total number of Scout and Navy bases because the American bases also include our air bases, marine bases, and army bases. We are never told which planets have army or marine bases but I think we can safely assume that they do exist which means we don't have any good way to do a total 'bases to bases' comparison.

Of the 800 bases only about 95 of those are Navy bases, or about 1 base per 3.4 M people. Scaling to the Imperium's population that should be about 5.3 M Navy bases, divided by 1377 gives you a factor of only 3,867 as opposed to 15,759.

And really, those final numbers are really pretty meaningless at the end of the day. Yes, it takes weeks to fly from one edge of the Imperium to the other but one large ship can easily protect (or threaten) a significantly larger area than a modern naval vessel meaning you need far fewer ships per capita for the Navy to be effective.
 
imperium (population 18,049,041,349,210, give or take)

I wanted to correct myself here. Reading through the T5SS thread, it turns out that the population multiplier n represents the interval [n, n+1) , so I have recounted Imperial population with that. The result is:
[18049041349233, 21832723838688]

So we can presume imperial population is somewhere between 18.05 trillion and 21.83 trillion.
 
Another factor is that the Imperium isn't technically concerned with what happens on the planets, only in the space between them.

Also, we can assume that the Imperium's ability to project force has scaled up since the 21st century. Maybe they need fewer ships now, by a factor of 100-200, and the "space between" jurisdiction accounts for another factor of 100-200, account for the entire 15,759 multiplier.
 
...Guam ... would have about 121 million personnel.

Oh, not going there, not even for the bad joke/quote I heard...

Ships that do 127c is fast, even if it takes a week.

The force multiplier of higher tech requires fewer soldiers, but may be offset by more supply and maintenance.
 
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[ . . . ]
My guess is that those are -not- 'giant military bases'. After all, when it was initially created Fort Wainwright only housed about 50 soldiers (yes, it has since expanded to around 7700 soldiers, but my point is that sometimes a government will feel that there needs to be some sort of presence in a location, even if it is a pretty small presence). Yes, they are bases and they are about the only thing around, hence the naming of the place as 'Depot', but they are not what most people in the Imperium would view as 'large'.
A large imperial power with centuries of history might design such a base to run with a skeleton crew for decades or centuries and then get spun up quickly when there is a need to deploy a large naval contingent into the region. Supply lines to a remote location will be expensive and even the Imperium might see the point in keeping it staffed with a skeleton crew in peacetime. A skeleton crew of 10,000 could actually be maintaining a very large mothballed facility and if fully activated the staff could grow by an order of magnitude or more. That 10,000 might be the base staff and a brigade sized garrison with some sort of rapid deployment capability. In peacetime the base might support a small detachment - maybe just a couple of cruisers plus auxiliaries. In wartime the base might have capacity to support an entire fleet.
 
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"Preserve OTU" is also an available tag. From the description it sounds like this is OTU, doesn't get reviewed, and is a placeholder for whatever a local referee decides is appropriate? The star positions are official but no other data gets assigned to those stars?

Also, this might be below your paygrade, so to speak, but what's the deal with the very regularly placed stars in The Beyond?



Centered around {-122.54259463549806`, 14} (Map coordinates). That doesn't appear like it could be natural random generation, but is tagged InReview OTU, meaning this is likely to be official, pending review?
That is the I'Sred*N Heptad Web of Worlds The sophonts are described as arachnid in The Beyond book, as is the illustration there. They are dangerous and xenophobic. Some of those mainworlds are asteroid belts in defiance of random generation. Gven all that, the "spiderweb-like pattern" thematic appearance of their empire worlds makes sense.
 
Color me amused, Some topics and lines of exploration seem to repeat themselves. Yes this topic has been discussed before, but not with such wonderful graphics.

I was considering chapter and verse of what had come before, but then the thought strikes me is all of those discussions used various differing assumption for world generation. While those sources have been referenced for the TravellerMap, the act of collating the map itself enforce a fair amount of uniformity. (Though if one did want to do some Paleo-Cartography I would suggest digging into the sector files accompanying the program Galactic.)

Though we have been talking Population spread, my recent contemplation is what is the native Gravity of the average Imperial citizen.
 
Color me amused, Some topics and lines of exploration seem to repeat themselves. Yes this topic has been discussed before, but not with such wonderful graphics.

I was considering chapter and verse of what had come before, but then the thought strikes me is all of those discussions used various differing assumption for world generation. While those sources have been referenced for the TravellerMap, the act of collating the map itself enforce a fair amount of uniformity. (Though if one did want to do some Paleo-Cartography I would suggest digging into the sector files accompanying the program Galactic.)

Though we have been talking Population spread, my recent contemplation is what is the native Gravity of the average Imperial citizen.

unless there's something I don't know about (easily possible), world density for all worlds across the Imperium isn't recorded anywhere, so we can't compute surface gravity except for the few worlds that it is mentioned.

The average world size is 5.30563 for all Im allegiance worlds, and presuming earth-mean density of 5.515 g cm^-3 (probably a bad assumption), the acceleration on an average sized imperial world would be 6.58236 m s^-2 ,

This isn't quite what you asked though, you asked what the average acceleration would be, not the surface acceleration on a world of average size. Since there are several non-linear terms, we'd have to get the distribution of worlds, make assumptions about density and then compute mean acceleration.

It could be done, but I'd probably have to throw out or assume 0 m s^-2 for world size 0.

Oh, and weight it for population per world, which we don't exactly know except for the cases the population is between 0 and 9.
 
unless there's something I don't know about (easily possible), world density for all worlds across the Imperium isn't recorded anywhere, so we can't compute surface gravity except for the few worlds that it is mentioned.

In general the earliest reference to gravity assumed that all terrestrial worlds shared a similar density as Earth, to the point calculations that as the standard density.

The average world size is 5.30563 for all Im allegiance worlds, and presuming earth-mean density of 5.515 g cm^-3 (probably a bad assumption), the acceleration on an average sized imperial world would be 6.58236 m s^-2 ,

Honestly 6.6g works for me as a generalization (General rounding and setting it in Traveller Assumptions of 1g = 10 m s^-2. Which generally matches the numbers provided in the Scouts book.

This isn't quite what you asked though, you asked what the average acceleration would be, not the surface acceleration on a world of average size. Since there are several non-linear terms, we'd have to get the distribution of worlds, make assumptions about density and then compute mean acceleration.

It could be done, but I'd probably have to throw out or assume 0 m s^-2 for world size 0.

Oh, and weight it for population per world, which we don't exactly know except for the cases the population is between 0 and 9.

Honestly you got close enough for overarching assumptions, which fine by me. The real question in depth is what is the gross environment of the world where the average person comes from.
 
Honestly you got close enough for overarching assumptions, which fine by me. The real question in depth is what is the gross environment of the world where the average person comes from.

The possible mean range is:

6.91184 - 6.91244 (m s^-2), depending on if the total imperial population is more toward the lower end of the counts we've been talking about or the higher end. About 0.704g, basically.
 
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The possible mean range is:

6.91184 - 6.91244 (m s^-2), depending on if the total imperial population is more toward the lower end of the counts we've been talking about or the higher end. About 0.704g, basically.

And accustomed to Thin atmosphere, I suspect.
 
And accustomed to Thin atmosphere, I suspect.

The average imperial citizen lives with an atmosphere of 5.21.

If you disregard vacuum atmospheres that changes to 5.63, which between Thin and Standard.

Counts of Imperial citizens living in each kind of atmosphere (hex codes converted to decimals so they could be averaged):
Code:
5	Interval[{3420958453473, 4115458778025}]
6	Interval[{2945989500913, 3526999420393}]
8	Interval[{2074450446383, 2536642816376}]
7	Interval[{1574589505903, 1912448801095}]
4	Interval[{1523926658051, 1826518666607}]
0	Interval[{1355775155914, 1646235367411}]
3	Interval[{1345950390301, 1629702666745}]
9	Interval[{1218251560840, 1498749805339}]
2	Interval[{992659528212, 1233251761533}]
1	Interval[{942467258282, 1114091854322}]
13	Interval[{198034283900, 232114440431}]
11	Interval[{195339834690, 237154907616}]
12	Interval[{128517892600, 152953430935}]
10	Interval[{118788498481, 154736383981}]
14	Interval[{13202541220, 15503786410}]
15	Interval[{139840070, 160951469}]

Regrettably the atmosphere codes really shouldn't be averaged. A "Thin, Low" atmosphere isn't more dense than a standard atmosphere, but it gets counted that way if you average codes. To do stats like this, the UWP should really have both an atmosphere mass code and an atmosphere composition code, then it's up to you to determine surface pressure based on the mass of the atmosphere.

So I realize that it's a little absurd to present an "average atmosphere" to three significant figures when some of those atmosphere types are meaningless for this computation, but it is probably safe to say the average atmospheric pressure is between Thin and Standard.
 
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sudnadja, you could recode the atmosphere code in a two dimension plot. Do this for each planet (or sophont).
Create two codes based on atmosphere. Mongoose and Cepheus lists atmo amd pressure values. While they are a range, they listed tainted or not as similar pressures
One is for the atmospheric pressure so
0 is vacuum (numeric 0)
1 is trace (numeric 1)
2,3 is vthin (numeric 2)
4,5 is thin (numeric 3)
6,7 is normal (numeric 4)
8,9 is dense (numeric 5)
D and E should be normal (numeric 4) as these codes refer to extremes of pressure worlds and people live at altitude/depths where pressure is normal.
A, B, C suggest normal
F Not sure

Now create a 2nd code for toxicity.
1,3,5,6,8,D,E is normal (numeric of 0)
2,4,7,9 is tainted (numeric of 1)
A,B,C is toxic (numeric of 2)
0 whatever amuses you
F Not sure

Now plot this in some manner maybe in a x/y cartesian plot pressure by toxicity.

The Mongoose/Cepheus table is below
Digit Atmosphere Pressure Survival Gear Required
0 None 0.00 Vacc Suit
1 Trace 0.001 to 0.09 Vacc Suit
2 Very Thin, Tainted 0.1 to 0.42 Respirator, Filter
3 Very Thin 0.1 to 0.42 Respirator
4 Thin, Tainted 0.43 to 0.7 Filter
5 Thin 0.43 to 0.7
6 Standard 0.71–1.49
7 Standard, Tainted 0.71–1.49 Filter
8 Dense 1.5 to 2.49
9 Dense, Tainted 1.5 to 2.49 Filter
10 (A) Exotic Varies Air Supply
11 (B) Corrosive Varies Vacc Suit
12 (C) Insidious Varies Vacc Suit
13 (D) Dense, High 2.5+
14 (E) Thin, Low 0.5 or less
15 (F) Unusual Varies Varies
 
I’ll take a shot at this in the evening, I am unfortunately crammed on an ~80 Dton aircraft traveling through the pre-contact terran atmosphere, and don’t have my computers available. Basically TL 0.

I am trying to keep the traveler universe in two categories, canon and then a 3d, more realistic version inspired by canon, and I’ll probably end up trying to generate more detailed atmosphere metrics, but I’ll give this a try.
 
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