Dynamics of Protoplanetary Disks
By Philip J. Armitage, 2011
Protoplanetary disks are the observational manifestation of the initial conditions for planet formation. They can be defined as rotationally supported structures of gas (invariably containing dust) that surround young, normally pre-main-sequence stars. Although most observed disks have inferred masses that are a small fraction of the stellar mass, no meaningful distinction can be drawn between physical processes in protoplanetary disks and those that occur in the earlier, protostellar phase, in which both star and disk are accreting rapidly. Similarly, a common set of processes operate, albeit to varying degrees, in disks around brown dwarfs, Classical T Tauri stars (low-mass pre-main-sequence stars that are actively accreting), and massive stars. A clear demarcation does separate protoplanetary disks from debris disks: dusty gas-poor structures around older stars whose properties reflect the collisional evolution of a population of small bodies (Wyatt, 2008).
Around low-mass stars, protoplanetary disks are persistent; the typical lifetime of ∼106 years (Haisch, Continue reading
“You don’t get it do you, I built this place. Down here I make the rules. Down here I make the threats. Down here… I’m God.“―The Trainman to Neo
The Trainman is an exile who created and operates Mobil Avenue and is a servant of another exile program known as the Merovingian.
After saving fellow Resistance member Axel, Niobe is approached by the Trainman in a subway station. While Niobe does not know who this person is, the Trainman tells her that Zion lasted 72 hours the last time it was attacked by the Machines (referring to the fifth iteration of the Matrix). When questioned about his identity, the Trainman states that he is only an observer of the events unfolding.
Later, the Trainman is approached by Morpheus, Seraph, and Trinity onboard a train. When he sees Continue reading
IF we analyse the principles of thought on which magic is based, they will probably be found to resolve themselves into two: first, that like produces like, or that an effect resembles its cause; and, second, that things which have once been in contact with each other continue to act on each other at a distance after the physical contact has been severed. The former principle may be called the Law of Similarity, the latter the Law of Contact or Contagion. From the first of these principles, namely the Law of Similarity, the magician infers that he can produce any effect he desires merely by imitating it: from the second he infers that whatever he does to a material object will affect equally the person with whom the object was once in contact, whether it formed part of his body or not. Charms based on the Law of Similarity may be called Homoeopathic or Imitative Magic. Charms based on the Law of Contact or Contagion may be called Contagious Magic. Continue reading
By Michael Dawson, 2010
Connectionism is the modern form of empiricist philosophy (Berkeley, 1710; Hume, 1748/1952; Locke, 1706/1977), where knowledge is not innate, but is instead provided by sensing the world.
“No man’s knowledge here can go beyond his experience” (Locke, 1706/1977, p. 83).
If recursion is fundamental to the classical approach’s rationalism, then what notion is fundamental to connectionism’s empiricism?
The key idea is association: different ideas can be linked together, so that if one arises, then the association between them causes the other to arise as well. Continue reading
The Matrix 101
Q: Morpheus doesn’t seem himself in Revolutions – he’s just not kicking butt with the confidence of the previous movies. What’s happened?
A: Morpheus has just learned from Neo that the prophecy is a lie. It’s another system of control engineered by the machines. While he’s likely not completely convinced of this yet, the simple fact is that this man has based his entire existence on finding the “One of Prophecy” to stop the war and free his people. Now, today, he’s been told his life’s work is a sham. This has a debilitating effect on Morpheus. He cannot lead any longer because he doesn’t know where to go next. It’s up to Neo, and Morpheus still believes in Neo, so he does what he has to do to support Neo. If that means co-piloting the Hammer with Niobe, he’ll do it. If it means being the first human to lay down his weapon when faced with hesitating Sentinels after the battle of Zion, he’ll do it. His role is not diminished, nor is his importance, but the path he’s following has changed. We learn the prophecy is a lie from The Architect’s conversation
A false awakening is a vivid and convincing dream about awakening from sleep, while the dreamer in reality continues to sleep. After a false awakening, subjects often dream they are performing daily morning rituals such as cooking, cleaning and eating. A subset of false awakenings, namely those in which one dreams that one has awoken from sleep that featured dreams, take on aspects of a double dream or a dream within a dream. A classic example is the double false awakening of the protagonist in Gogol’s Portrait (1835).
A false awakening may occur following a dream or following a lucid dream (one in which the dreamer has been aware of dreaming). Particularly, if the false awakening follows a lucid dream, the false awakening may turn into a “pre-lucid dream”, that is, one in which the dreamer may start to wonder if they are really awake and may or may not come to the correct conclusion. In a study Continue reading
“1408” is a short story by Stephen King. It is the third tale in the audiobook collection titled Blood and Smoke, released in 1999. In 2002, it was collected in written form as the 12th story in King’s collection Everything’s Eventual.
In the introduction to the story, King says that “1408” is his version of what he calls the “Ghostly Room at the Inn”, his term for the theme of haunted hotel or motel rooms in horror fiction. He originally wrote the first few pages as part of an appendix for his non-fiction book, On Writing (2000), to be used as an example of how a story changes from one draft document to the next. King also noted how the numbers of the title add up to the supposedly unlucky number 13. Continue reading