CapnTrippy's New Writeups

Swimming in spacetime (idea)

2003-07-29T11:30:49Z

Did you know that its possible to swim in the cold, hard vacuum of space, even though you have nothing to push against? Well according to Jack Wisdom from M.I.T. you can; admittedly not very far, and the space-time has to be curved. But even so its the principle here that counts and this unlikely result appears correct.

This "thrust" doesn't arise from some wacky warping of space, gravity waves or manipulation of zero-point energy, but is due to conservation of momentum and the geometry of the whole system. Although it takes some maths thats way above my head to prove it, Jack starts simply considering two concentric spheres in flat space, connected at their centres. When one is rotated, the whole orientation of the system changes, due to conservation of angular momentum. You see this effect all the time, if you hold a heavy spinning disk by its axle, whilst sat on a office swivel chair, then by changing the angle of the disk, you can rotate…

Zwicker tone (idea)

2003-07-11T15:37:35Z

Introduction

We are all used to the idea of optical illusions, but auditory illusions also exist. One such is the 'Zwicker tone', first characterised by Eberhard Zwicker at Bell Labs in 1964.

The illusion is created by playing a subject (for a few seconds) broad spectrum white noise that contains a frequency gap, i.e. if you were to play it through a spectrum analyser all the bars would be at maximum, except one. Then sound is then turned off, and even though there is complete silence, the subject hears a very faint, pure tone of about equal frequency to the frequency gap in the noise. In essence the effect is like brief tinnitus lasting only a few seconds. Various configurations of noise, silence and the addition of a pure tone can give differing, or indeed no Zwicker tone. Various configurations, and their effects are shown below (reproduced from reference 1)


(a)                  (f)
 ^                     ^

…

thixotropy (idea)

2003-02-05T12:47:29Z

It was Herbert Max Finlay Freundlich a physical chemist who coined the term thixotropy ('change by touching') in 1935 during his research on gels. The standard scientific definition of thixotropy is usually given along the lines of :-

A decrease of viscosity under constant shear stress or shear rate, followed by a time dependant recovery when the shear load is removed.

Hmmm... Like reading the unix man pages, you get a good definition, in a way that takes even more work to find out what the meaning of it is. An example here will be more illuminating I feel; tomato ketchup. The reason why it doesn't flow out of the bottle is because it is a thixotropic liquid. When its sitting on the shelf, the shear stress/load is zero and the molecules/components making it up take on a more ordered structure by forming inter-molecular bonds (usually through hydrogen bonding),…

multiverse (idea)

2003-01-03T00:56:03Z

First a caveat, the following is largely the product of mine and one of my friend's late night discussions and so at best (I hope) will be a piece of entertaining philosophy, and at worst a load of dingo's kidneys. If you have the patience and forbearance gentle reader, then please read on and let me know your comments. ¹

Towards the Multiverse

The many-worlds hypothesis states that at any one point in time the universe we live has one co-ordinate in a phase space, and it could be said that the laws of (quantum) physics determine the probability of going from this point to any other within this phase space. (That is to say; one arrangement of stuff going to a different arrangement of stuff)

Is there a level of complexity above this? Well if you consider that the phase space our universe has generated, its dimensionality will be determined by the amount of 'stuff' you started with, and any path through it describing its evolution b…

epibatidine (thing)

2002-07-09T12:45:23Z

Introduction

Epibatidine is a potent analgesic of the alkaloid family of drugs. It was first isolated from a frog (Epipedobates tricolor) found in the rain forests of Equador by Dr. John Daly of the National Institutes of Health in the USA in 1974. Using the Straub tail response test on mice it was found to be 200 times as effective as morphine. However only about 750 millgrams was ever extracted from this rare type of frog, and political reasons made it impossible to go back and juice more of them to extract the compound. When in the 1980's an international treaty banned the collection of many species, including this frog, Daly was forced to try and breed the frogs in captivity. Although the frogs survived, their skins did not contain the the compound with the analgesic effect. It is possible therefore the frogs do not biochemically produce it, but may ingest it in their natural habitat, extracting then secreting it.In the 1970's and 1980's…

Wilma Deering (person)

2002-05-10T23:11:13Z

A colonel and star fighter pilot of the Earth Directorate in the year 2491; companion to Buck Rogers throughout many 'epic' adventures in the television series and films, Buck Rogers in the 25th Century!.

Played by the actress and model Erin Gray, Wilma's no-nonsense tough character actually gave many girls the inspiration to become pilots themselves, as well as providing sex appeal for the boys! In the first series Gray a natural brunette had to dye her hair blonde to fit the roll, something that gave her some consternation, as she worried about the long term damage it might do her hair. At this time she was still working as a model, and so as a compromise the studio came up with a hair style of blonde at the front and brown at the back. Also she thought the character to impersonal and cold, and the scenes that showed a softer side to Wilma were always edited out. During the second series, on board the space ship Searcher this…