OpenLLM-France/wikimedia huggingface dataset:
# Human Geography AP/Gravity model

The Gravity Model is a model used to estimate the amount of interaction between two cities. It is based on Newton's universal law of gravitation, which measured the attraction of two objects based on their mass and distance. The gravity model for cities works in the same way; the amount of interaction between two cities is proportional to the size of the cities and inversely proportional to their distance squared. This explains why cities that are far apart, such as New York and Los Angeles, still interact a lot despite being on either side of the United States, thousands of miles apart.
# Human Nature: Catholic Thought and the Sciences/Contraception and Abortion

The claim is often made, sometimes by opponents of Catholic teaching on contraception, that the availability of contraception reduces the prevalence of abortion. This is a topic of much research, including at least one study that contradicts it.

## External Links

First Things: The Myth of the Contraceptive Compromise
# Human Nature: Catholic Thought and the Sciences/Culture and Religion

The idea of culture plays a role in many Church teachings. Catholic doctrine draws fine distinctions between the importance of distinct cultures and the universality of morality and the Christian Gospel.
# Human Digestive System/Stomach

The stomach is the place where food and liquids that pass from the esophagus are stored and prepared for digestion.
The upper part of the stomach is called the fundus (See part A). This part of the stomach stretches to make room for large meals. The food and liquid is then ground up by the lower part of stomach, called the pylorus (See part D). As the food is broken down to tiny particles, stomach juices, including acid and pepsin, begin to break down the food further. Liquids tend to leave the stomach first. When the food is small enough, it passes through the pyloric valve, into the small . The stomach is thick walled.
# Human Nature: Catholic Thought and the Sciences/Climate Change

The relation of Catholic doctrine to climate change is expressed in the Compendium of the Social Doctrine of the Church:
    Programs of economic development must carefully consider “the need to respect the integrity and the cycles of nature” because natural resources are limited and some are not renewable. The present rhythm of exploitation is seriously compromising the availability of some natural resources for both the present and the future. Solutions to the ecological problem require that economic activity respect the environment to a greater degree, reconciling the needs of economic development with those of environmental protection. Every economic activity making use of natural resources must also be concerned with safeguarding the environment and should foresee the costs involved, which are “an essential element of the actual cost of economic activity”. In this context, one considers relations between human activity and climate change which, given their extreme complexity, must be opportunely and constantly monitored at the scientific, political and juridical, national and international levels. The climate is a good that must be protected and reminds consumers and those engaged in industrial activity to develop a greater sense of responsibility for their behaviour.
    An economy respectful of the environment will not have the maximization of profits as its only objective, because environmental protection cannot be assured solely on the basis of financial calculations of costs and benefits. The environment is one of those goods that cannot be adequately safeguarded or promoted by market forces. Every country, in particular developed countries, must be aware of the urgent obligation to reconsider the way that natural goods are being used. Seeking innovative ways to reduce the environmental impact of production and consumption of goods should be effectively encouraged.
    Particular attention will have to be reserved for the complex issues surrounding energy resources. Non-renewable resources, which highly-industrialized and recently-industrialized countries draw from, must be put at the service of all humanity. From a moral perspective based on equity and intergenerational solidarity, it will also be necessary to continue, through the contribution of the scientific community, to identify new sources of energy, develop alternative sources and increase the security levels of nuclear energy. The use of energy, in the context of its relationship to development and the environment, calls for the political responsibility of States, the international community and economic actors. Such responsibility must be illuminated and guided by continual reference to the universal common good.
    (#470, emphasis original)
# Human Geography AP/Unit Outline
### Geography – Its nature and perspectives

This unit focuses on fundamental concepts and tools that are integral to a comprehensive understanding of human geography. Consider it an “introduction to the course.” By the end of this unit you should have a clearer sense of what the course is about. Keep in mind that the concepts and tools covered are only meant as an introduction. Your teacher will probably be using these items consistently throughout the course.
# Human Nature: Catholic Thought and the Sciences
## Contents

* How to Contribute
* Introduction
* Human Origins and God
* The Body and Healing
* The Brain and the Person
* Psychology and Spirit
* Culture and Religion
* Sociology and the Church
* Economics and the Kingdom

## Sample Pages

* Contraception and HIV
* Exorcism
* Just Wages
* Original Sin
* Pornography
# Guide to The Lord of the Rings/The Hobbit/Chapter 11

The Hobbit Chapter 11 - On the Doorstep

## Plot

The townsmen help the expedition trough the lake and to the bottom of the Lonely Mountain. The expedition set out through the Desolation of the Dragon, a waste land. They come across the ruined settlement of Dale, a casualty of Smaug.
The expedition are unable to find a way, as they have forgotten. They have pupt effort through axes, picks, but to no avail.
The few days they try, it is revealed that their efforts were futile. Bilbo sees a snail near the door and is reminded of ELron's story about the keyhole being revealed on Durin's Day. Bilbo and the dwarves wait for the setting sun to reveal the hidden keyhole and Thorin opens the door with the key that was given by Gandalf along with the map.

## Analysis

This chapter reveals the fulfillment of Elrond's prophecy. Thorin's claim gains legitimacy when the door opens with the key. The magic surrounding Durin's Day is connected in similarity to ancient pagan beliefs surrounding the equinox and solstice.

## Characters

* Thorin
* Bilbo

### Mentioned

* Smaug
* Elrond
* Durin

## Locations

* Lonely Mountain
* Dale
# Guide to The Lord of the Rings/The Hobbit/Chapter 12

The Hobbit Chapter 12 Inside Information

## Synopsis

The dark passage into the mountain stands open before the Company. Thorin nominates Bilbo to go inside first. Bilbo enters, puts on the ring, and proceeds down the passage into Smaug’s lair. There, he sees the dragon asleep on piles of treasure. Bilbo is horribly afraid, but he works up the nerve to take a single golden cup from one of the piles. He rushes back up to the dwarves, who marvel over the cup.
Bilbo’s theft does not go unnoticed by Smaug, who takes careful account of the treasure. When he awakens, he is enraged to discover the cup is missing. He flies around the mountain breathing blasts of flame, and devours the ponies that belonged to the Company. Meanwhile, the dwarves and Bilbo huddle inside the secret passage, terrified. After a while, Smaug returns to his den and falls asleep. Bilbo works up the nerve to return to the dragon’s lair, only to discover that Smaug was just pretending to be asleep.
Although he cannot see Bilbo because of the ring, Smaug smells him and greets him mockingly. Bilbo answers Smaug only in riddles, which amuses the dragon enough to quell his anger. Cleverly, Bilbo flatters Smaug into displaying his underbelly, revealing an open patch in Smaug’s "diamond waistcoat" above his left breast.
Bilbo rushes back up the passage, just outrunning the dragon’s angry flames. He tells the dwarves all that he has learned while a thrush sits nearby and seems to listen. They hear the roar of the dragon once more and close the secret passage just before an avalanche comes down upon it, and they become trapped inside the mountain.

## Analysis

Bilbo has to undertake the traditional task of the hero.
Bilbo confronts Smaug the dragon, matching with with conversation. During the conversation, he looks for a weak spot, which he spots. The fact that Bilbo brings back an item, he proves he has accomplished the act of entering a place of danger.

## Characters
### Main

* Bilbo Baggins
* Smaug
* Thorin Oakenshield
* Balin

### Other characters

* Fíli and Kíli
* Bifur
* bofur
* Bombur
* Girion (Mentioned only)

## Locations

* Lonely Mountain

## Glossary

* staggerment amazement, confusion

## Objects

* One Ring

## Places

* The Lonely Mountain
# Guide to The Lord of the Rings/The Hobbit/Chapter 14

Fire and Water is the fourteenth chapter of J.R.R Tolkien's The Hobbit.

## Plot

Smaug attacks Lake Town after leaving the Lonely Mountain. The men of Esgaroth see the dragon coming and manage to fight back, but all seems lost until the thrush lands on Bard’s shoulder and informs him of Smaug's weak spot. Bard slays the dragon, but Esgaroth is destroyed in the process. Meanwhile, Thranduil assembles a host of Elves and marches to the Lonely Mountain with the intent of claiming the now unguarded treasure.

## Synopsis

This chapter is devoted entirely to Smaug seeking vengeance against Lake-town for assisting Bilbo and the dwarves. The people of Lake-town see the dragon coming in the distance and prepare archers and many buckets of water to douse the coming flames. Their readiness is of little help, for Smaug flies over and sets the entire town on fire. The men’s arrows bounce harmlessly off the dragon’s body. When most of the men have abandoned the town, Bard, the captain of the archers, readies his last arrow. Suddenly, the thrush from the mountain lands on his shoulder and tells him to look for the dragon’s weak spot in the hollow of his left breast. Bard sees the open patch and fires his arrow. It plunges through the chink in the dragon’s armor and buries itself in his heart. Smaug comes crashing down, destroying what is left of Lake-town as he dies. Bard dives into the water and joins the rest of his people, who are mourning the dead and their lost town. Some blame the dwarves for waking the dragon, but most assume that they too are dead. The townsfolk then realize the treasure in the Lonely Mountain is now unguarded, and they think eagerly of how the wealth could rebuild Lake-town.
News of Smaug’s death spreads quickly, bringing the Elvenking and an army of elves to Lake-town to lend aid. The humans and elves unite in a single army and march toward the Lonely Mountain, with the intent of taking the treasure.

## Analysis

The account of the destruction of Lake Town, the town of humans, attests and emphasizes the formidable power and might of Smaug. Bard appears for the first time and becomes a hero. He kills the dragon by shooting an arrow into the weak spot that Bilbo had observed earlier. Interestingly, a thrush was the creature that reminded Bilbo of Durin's Day and allowed the dwarves to unlock the secret opening to Smaug's lair.

## Main

* Smaug
* Bard the Bownman
* Master of Laketown
* Elvenking

### Other characters

* Girion (Mentioned only)
* Thorin (Mentioned only)

### Locations

* Guide to The Lord of the Rings/Places/Esgaroth
* Guide to The Lord of the Rings/Places/Dale (Mentioned only)
* Guide to The Lord of the Rings/Places/Lonely Mountain (Mentioned only)

### Objects

* Black Arrow

## Events

* Death of Smaug
# Guide to The Lord of the Rings/The Hobbit/Chapter 15

The Gathering of the Clouds is the fifteenth chapter of J.R.R Tolkien's The Hobbit.

## Plot

Bilbo and the Dwarves learn of Smaug's death, and of the approaching hosts of the Mirkwood Elves and the lake-men, from Roäc the Raven. The Dwarves send messages via ravens to Dáin of the Iron Hills requesting aid, and the dwarves have the ravens report the movements of any who approach the Lonely Mountain. Bard comes before the front gate of the mountain and requests a parley, but Thorin refuses. After another attempt at parley, the Elves and men declare the mountain besieged.

## Synopsis

The thrush returns to the Company in Ravenhill. Finding that they cannot understand its speech, the thrush brings an old raven that can speak in the common tongue, and the raven informs them of Smaug's death. Their rejoicing is short-lived, as the raven goes on to describe the army of humans and elves marching toward them, as well as the suffering of Lake-town’s people, who feel they deserve some share of the treasure in the mountain. Thorin regards the treasure as his inheritance and plans to fight for it, regardless of what the people of Lake-town have suffered.
Under Thorin’s orders, the Company retreats to the mountain and fortifies it by building a wall at the main gate. From there, they watch as Bard and representatives of the elves approach. Bard informs them that he killed Smaug and Lake-town has been destroyed, and asks that the dwarves be generous in sharing the treasure, since they benefited so much at the expense of the humans. Thorin flatly refuses, and feels that he owes them nothing since the gold belonged to his people originally. Bard gives Thorin time to reconsider, but Thorin will not change his position. The mountain is then declared besieged: no one will be let in or out without being captured or killed. Bilbo, for his part, would gladly share the treasure, and is entirely discouraged by the whole turn of affairs. However, no dwarf questions Thorin, and Bilbo has no say in the matter.

## Appearances
### Main Characters

* Thorin Oakenshield
* Bilbo Baggins
* Balin
* Roäc
* Bard the Bowman

### Other characters

* Elvenking
* Smaug (Mentioned only)
* Thrpr (Mentioned only)
* Girion (Mentioned only)

### Species

* Hobbits
* Dwarves
* Men
* Elves
* Dragons

## Locations

* Lonely Mountain
* Ravenhill (Mentioned only)
* Mirkwood (Mentioned only)
* Esgaroth (Mentioned only)

### Objects

* Arkenstone
# Introduction to Astrophysics/Stars/Classification

Stellar classification is the classification of stars based on their spectral characteristics.
Currently, most stars are classified under the Morgan-Keenan system (MK)., where each star is assigned a spectral class from the older Harvard classification and a luminosity class using Roman numerals, forming the star's spectral type.

## Conventional colour description

The conventional colour description only looks at the peak of the stellar spectrum. In actuality, though, stars radiate in all parts of the spectrum and because all spectral colours combined appear white, the colours the human eye would see are far lighter than the conventional colour descriptions would suggest. Meaning, the simplified assignment of colours of the spectrum can be misleading. For example, so-called red dwarfs are a deep shade of orange and brown dwarfs would hypothetically appear to a nearby observer as a dim grey.

## Modern classification

As described above, the modern classification system used is the Morgan-Keenan system (MK). Stars are given labels such as G2 (the Sun) or K1.5 (Arcturus). They are composed of the Harvard spectral classification (O, B, A, F, G, K and M, ranging from the hottest to the coldest), and a Roman numeral also ranging from the hottest (0) to the coldest (9).
Other modern systems, (e.g. the UBV system) are based on colour indexes - the measured differences in three or more colour magnitudes. Those numbers are given labels such as "U-V" (Ultraviolet) or "B-V" (Blue and Visual), which represent the colours passed by two standard filters.

## Harvard spectral classification

The Harvard system, which was developed by the astronomer Annie Jump Cannon, is a simple alphabetical classification. Physically, the classes indicate the temperature of the star's atmosphere (effective temperature) and are normally listed from hottest to coldest.
| Class | Effective temperature | Vega-relative chromaticity | Chromaticity (D65) | Main-sequence mass (solar masses) | Main-sequence radius (solar radii) | Main-sequence luminosity(bolometric) | Hydrogen lines | Fraction of all main-sequence stars |
| O | ≥ 30,000 K | blue | blue | ≥ 16 M | ≥ 6.6 R | ≥ 30,000 L | Weak | ~ 0.00003 % |
| B | 10,000 - 30,000 K | blue white | deep blue white | 2.1 - 16 M | 1.8 - 6.6 R | 25 - 30,000 L | Medium | 0.13 % |
| A | 7,500 - 10,000 K | white | blue white | 1.4 - 2.1 M | 1.4 - 1.8 R | 5 - 25 L | strong | 0.6 % |
| F | 6,000 - 7, 500 K | yellow white | white | 1.04 - 1.4 M | 1.15 - 1.4 R | 1.5 - 5 L | Medium | 3 % |
| G | 5,200 - 6,000 K | yellow | yellow white | 0.8 - 1.04 M | 0.96 - 1.15 R | 0.6 - 1.5 L | weak | 7.6 % |
| K | 3,700 - 5,200 K | light orange | pale yellow orange | 0.45 - 0.8 M | 0.7 - 0.96 R | 0.08 - 0.6 L | Very weak | 12.1 % |
| M | 2,400 - 3,700 K | orange red | light orange red | 0.08 - 0.45 M | ≤ 0.7 R | ≤ 0.08 L | Very weak | 76.45 % |
# Introduction to Astrophysics/Stars/Hertzsprung-Russell

The Hertzsprung-Russell diagram (usually referred to by the abbreviation H-R diagram or HRD, also known as a Colour-Magnitude (CM) diagram) shows the relationship between absolute magnitude, luminosity, stellar classification, and surface temperature of stars. The diagram was created circa 1910 by Ejnar Hertzsprung and Henry Norris Russell, and represented a huge leap forward in understanding stellar evolution, or the 'lives of stars'.

## Interpretation

There are two equivalent forms. One is the observer's form which plots the color index of the star on one axis and the absolute magnitude on the other axis. These two quantities can be derived from observations. The theoretician's form plots the temperature of the star on one axis and the luminosity of the star on the other. These two quantities can be calculated from computer models.
The exact transformation from one to the other is not trivial, and depends on the model being used and their parameters (like age and composition). See Sekiguchi and Fukugita, for example, for a transformation between B-V color index and temperature.
The H-R diagram is used to define different types of stars and to match theoretical predictions of stellar evolution using computer models with observations of actual stars.
Most of the stars occupy the region along the line called main sequence. During that stage stars are burning hydrogen. Next concentration of stars is on horizontal branch (helium fusion in the core and hydrogen burning in a shell surrounding the core). Another prominent feature is Hertzsprung gap located in the region between A5 and G0 spectral type and between +1 and -3 absolute magnitudes (i.e. between the top of main sequence and the giant stars in the horizontal branch). RR Lyrae stars can be found in the left of this gap. Hertzsprung gap is a subset of instability strip. In the upper section of instability strip Cepheid variables are residing.
The H-R diagram is also used by scientists to help the figure out roughly how far away the stars are from Earth. This can be done if we know the apparent magnitude we can plot the star onto the graph using its spectral class and the type of star it is. We can then use the graph to deduce the absolute magnitude of the star.

## External links

* Sekiguchi and Fukugita, AJ 120, 1072 (2000)
# Introduction to Astrophysics/Vacuum Energy

Vacuum energy is an underlying background energy that exists in space throughout the entire Universe. One contribution to the vacuum energy may be from virtual particles which are thought to be particle pairs that blink into existence and then annihilate in a timespan too short to observe. They are expected to do this everywhere, throughout the Universe. Their behavior is codified in Heisenberg's energy–time uncertainty principle. Still, the exact effect of such fleeting bits of energy is difficult to quantify.
The effects of vacuum energy can be experimentally observed in various phenomena such as spontaneous emission, the Casimir effect and the Lamb shift, and are thought to influence the behavior of the Universe on cosmological scales. Using the upper limit of the cosmological constant, the vacuum energy of free space has been estimated to be 10−9 joules (10−2 ergs) per cubic meter. However, in both quantum electrodynamics (QED) and stochastic electrodynamics (SED), consistency with the principle of Lorentz covariance and with the magnitude of the Planck constant requires it to have a much larger value of 10113 joules per cubic meter.This huge discrepancy is known as the vacuum catastrophe.
# Introduction to Astrophysics/Laws and Formulae
## Gravitation
### Kepler's Laws

* The orbit of each planet is an ellipse which has the sun at one of its foci.
* Each planet moves in such a way that the line joining it to the sun sweeps out equal areas in equal times.
* The squares of the periods of revolution of the planets about the Sun are proportional to the cubes of their mean distance from it.

### Newton's gravitational law

$F=G{\frac {m_{1}m_{2}}{r^{2}}}$
| F = | The gravitational force between two bodies. |
| G = | Universal gravity constant, 6.67 x 10$^{−11}$ N m$^2$ kg$^{−2}$ |
| m$_1$ = | The mass of the first body. |
| m$_2$ = | The mass of the second body. |
| r = | The distance between the centres of mass of two bodies. |

## Black body radiation

Wein’s displacement law(only for black bodies)
λ$_{max}$ = W/T
Wein’s constant(W)= 2.90 × 10$^{−3}$ m K
T= temperature of the black body

### Stefan's Law

$E={\sigma }{T^{4}}$
| E = | Rate of energy radiated from the surface of a black body per unit area. |
| σ = | Stefan's constant, 5.67 × 10$^{−8}$ W m$^{−2}$ K$^{−4}$ |
| T = | Surface temperature of the black body. |

## Stellar Magnitude
### Apparent Magnitude

$m=-2.5\log _{10}I+K$
| m = | Apparent magnitude of star. |
| I = | Intensity of light received. |
| K = | a constant |

### Pogson's Formula

$m_{1}-m_{2}=2.5\log _{10}\left({\frac {I_{2}}{I_{1}}}\right)$
| m$_1$ = | Apparent magnitude of first star. |
| m$_2$ = | Apparent magnitude of second star. |
| I$_1$ = | Intensity of light received from first star. |
| I$_2$ = | Intensity of light received from second star. |

### Absolute Magnitude

$m-M=5\log _{10}\left({\frac {d}{10}}\right)$
| m = | Apparent magnitude of star. |
| M = | Absolute magnitude of star. |
| d = | Distance to star in parsecs. |
# Introduction to Astrophysics/Red Giants

A red giant is a phase most typical stars (i.e. the sun) go through. During this phase, the star inflates to hundreds of times its original size. After the red giant phase the star shrinks and becomes a white dwarf star.
# Introduction to Astrophysics/Stars/Luminosity

Luminosity is a measure of energy flux. This is the rate of flow of energy per unit area per unit time from the surface of the body. Luminosity depends both on the temperature of the body and the size of the body. We assume that a body like the Sun emits radiation effectively as a black body. This means it can be modelled using Stefan-Boltzmann's Law.
L ∝ R$^2$T$_{eff}$$^4$ Which gives us L = 4πR$^2$σT$_{eff}$$^4$
Where T$_{eff}$ = 5777 K and Stefan-Boltzmann constant: σ = 5.670400 × 10$^{−8}$ W·m$^{-2}$·K$^{-4}$
Example: What is the Solar luminosity at the surface of the Sun?
Radius of Sun: R$_{sun}$ = 6.96 × 10$^8$ m
L = 4 × π × (6.96 × 10$^8$ m)$^2$ × 5.670400 × 10$^{−8}$ W·m$^{-2}$·K$^{-4}$× (5777 K)$^4$ = 3.85 × 10$^{26}$ W