An interview with David Conyers, from Albedo One Magazine
"Do transhuman characters with god-like powers alienate readers? Are they too far removed from human emotions and frailties that we experience in modern society?
The frailty of our bodies is an enormously important part of our current reality — and I very much doubt that anyone will ever be literally immortal — but I don't think there's anything all that strange or alienating about the prospect of having, say, a far more robust body, or back-up copies of your mind. These are just ways of enabling us to do the kind of constructive things we're doing right now, with fewer unwelcome interruptions. If you asked someone who'd moved from a country with endemic violence, women dying in childbirth, high infant mortality, and no effective treatment for dozens of infectious diseases to a place where all of those problems had been solved whether they felt alienated by the loss of their precious human frailty, they'd just laugh."
5 out of 5
http://www.gregegan.net/INTERVIEWS/Interviews.html
Sunday, June 20, 2010
Friday, June 18, 2010
Gummelt Applet - Greg Egan
"Gummelt draws Petra Gummelt's quasiperiodic tiling of the plane with overlapping decagons.
Decagonal tile
This tiling is related to the rhombic Penrose tiling, with a decagon associated with each “fat” rhomb, and the side-matching rules replaced by the requirement that wherever two decagons overlap, the coloured darts they contain are superimposed. Each decagon contains four darts, two of them pointing clockwise and two pointing counter-clockwise, with one pair overlapping."
4 out of 5
http://www.gregegan.net/APPLETS/06/06.html
Decagonal tile
This tiling is related to the rhombic Penrose tiling, with a decagon associated with each “fat” rhomb, and the side-matching rules replaced by the requirement that wherever two decagons overlap, the coloured darts they contain are superimposed. Each decagon contains four darts, two of them pointing clockwise and two pointing counter-clockwise, with one pair overlapping."
4 out of 5
http://www.gregegan.net/APPLETS/06/06.html
With "Zendegi," Greg Egan plunges us into the techno-future of Iran - Chris Braak
"In Zendegi, Greg Egan has created a beautiful, brilliant, near-future world that expertly explores the consequences of mind-mapping technology in the politically volatile world of Iran."
3.5 out of 5
http://io9.com/5564075/with-zendegi-greg-egan-plunges-us-into-the-techno+future-of-iran
3.5 out of 5
http://io9.com/5564075/with-zendegi-greg-egan-plunges-us-into-the-techno+future-of-iran
Wednesday, June 16, 2010
Aurealis interview 2009 - Greg Egan
By Russell Blackford :-
"7. Blackford: Is it similar when you deal with advanced scientific and mathematical concepts—concepts that might “lose” even readers with reasonable levels of scientific literacy—or do you see that as a different kind of problem? Again, I'm interested in how it feels from the inside to an author writing this kind of work that could be challenging to an audience and must be extraordinarily challenging to create.
Egan: When scientists and mathematicians think about “advanced” concepts, what they're really doing mostly just involves some relatively simple manipulation of ideas that happen to be unfamiliar to the wider population. There are plenty of card games whose rules are more complex than the rules for doing tensor calculus! So depending on the context, I'll sometimes just try to give the reader the gist of what those manipulations are, even if they're going to be a little bit hazy about the things being manipulated. At other times, I'll do as much as I can to unpack the whole process and demystify it completely. It's impossible to write about every topic in modern science in a way that absolutely anyone can follow, but I'm not afraid to transcribe characters having detailed thoughts or conversations in which they make sense of scientific ideas, and by eavesdropping on those conversations the reader gets invited into the loop."
Originally “Aurealis interview”
Aurealis #42, August 2009. Interview by Russell Blackford.
5 out of 5
http://www.gregegan.net/INTERVIEWS/Interviews.html
"7. Blackford: Is it similar when you deal with advanced scientific and mathematical concepts—concepts that might “lose” even readers with reasonable levels of scientific literacy—or do you see that as a different kind of problem? Again, I'm interested in how it feels from the inside to an author writing this kind of work that could be challenging to an audience and must be extraordinarily challenging to create.
Egan: When scientists and mathematicians think about “advanced” concepts, what they're really doing mostly just involves some relatively simple manipulation of ideas that happen to be unfamiliar to the wider population. There are plenty of card games whose rules are more complex than the rules for doing tensor calculus! So depending on the context, I'll sometimes just try to give the reader the gist of what those manipulations are, even if they're going to be a little bit hazy about the things being manipulated. At other times, I'll do as much as I can to unpack the whole process and demystify it completely. It's impossible to write about every topic in modern science in a way that absolutely anyone can follow, but I'm not afraid to transcribe characters having detailed thoughts or conversations in which they make sense of scientific ideas, and by eavesdropping on those conversations the reader gets invited into the loop."
Originally “Aurealis interview”
Aurealis #42, August 2009. Interview by Russell Blackford.
5 out of 5
http://www.gregegan.net/INTERVIEWS/Interviews.html
Quote - Greg Egan
" Keep using crappy software, or the AI overlord will eat your children."
5 out of 5
http://www.gregegan.net/INTERVIEWS/Interviews.html
5 out of 5
http://www.gregegan.net/INTERVIEWS/Interviews.html
Tuesday, June 15, 2010
Schwarz Applet - Greg Egan
"Schwarz performs two successive Schwarz-Christoffel transformations of the complex plane: f(z)=1+(z–z0)/(1–z0*z), which maps z0 to 1 and the unit disk centred on 0 to the unit disk centred on 1, and g(z)=(z+1)/(z–1), which maps 1 to infinity and the unit disk centred on 0 to half the complex plane; z0 is either a random point, or the point where you last clicked the mouse."
4 out of 5
http://www.gregegan.net/APPLETS/05/05.html
4 out of 5
http://www.gregegan.net/APPLETS/05/05.html
Laplace Applet - Greg Egan
"Laplace displays solutions of Laplace's equation in three dimensions, sampled on the surface of a sphere. The intensity of each colour cycles between two randomly oriented spherical harmonics — functions whose angular dependence has a simple pattern of regularly spaced peaks and troughs."
4 out of 5
http://www.gregegan.net/APPLETS/04/04.html
4 out of 5
http://www.gregegan.net/APPLETS/04/04.html
Cantor Applet - Greg Egan
"Cantor is a 2-dimensional Cantor set, a square divided into nine parts with the middle rectangle removed, and the same process applied to the other eight rectangles, ad infinitum. The black region is the Cantor set; the gaps are decorated. A version where all the rectangles are identical squares can be described mathematically as the set of (x,y) such that x and y lie between 0 and 1 and contain no 1s in their base 3 representation (e.g. 0.02202 would be in the set), repeatedly excluding the middle third of both coordinates."
4 out of 5
http://www.gregegan.net/APPLETS/03/03.html
4 out of 5
http://www.gregegan.net/APPLETS/03/03.html
Sunday, June 13, 2010
Dark Integers - Greg Egan
Novelette
Number of words : 16300
Percent of complex words : 11.9
Average syllables per word : 1.5
Average words per sentence : 22.9
READABILITY INDICES
Fog : 13.9
Flesch : 53.6
Flesch-Kincaid : 11.5
PEOPLE
Bruno Costanzo
Mathematical defect mapper and watcher.
Sam
Bruno's counterpart on the far side.
Alison Tierney
Bruno's friend and co-watcher.
Yuen
Alison's mentor.
Laura
Alison's daughter.
Tim Campbell
A number theory researcher working at Victoria University.
Kate
Bruno's girlfriend.
Machiavelli
Political theorist.
Gerard Hooft
Quantum mathematician.
Bridget
Campbell's wife, an organic chemist. Also a lecturer at Victoria University.
Richard Branson
English billionaire.
Brando
An actor.
Hedy Lamarr
An actress.
Genghis Khan
Mongol warlord.
ORGANISATIONS
Industrial Algebra
Company that wants to exploit Bruno and Alison's discovery.
Victoria University
In Wellington.
JJJ
Radio station, focused on new music for the young.
PLACES
Sydney
Australian city.
Shanghai
Major city in China.
Zurich
Where Alison lives.
West Ryde
Suburb of Sydney.
Tasman
Sea between Australia and New Zealand.
Blue Mountains
Outside Sydney.
Penrith
Sydney suburb.
MEDIA
The West Wing
American tv show.
Dick Tracy
Comic strip detective.
Dr Strangelove
Bomb movie.
CONCEPTS
Planck scale
Very, very small. Physics measurement.
Dark Integers
A type definition of 4096 bits.
Fields Medal
Prize awarded to young mathematicians.
VEHICLES
Sputnik
Russian spacecraft.
PLOT
Ten years after Luminous, Bruno, Alison and an ill Yuen work to keep a detente with the far side, who are led by Sam as their contact.
When a New Zealand number theorist makes a discovery on his own, this threatens cordial relations, and Bruno has to scramble to get him onside. As he doesn't want to kill him, being Alison's other option.
Further work of Campbell's allows him to map the other side, showing their space is different, they are in a different solar system, and have different life.
Conflict starts, and changing mathematical axioms can do bad things, like crash markets and make planes fall out of the sky, killing many people.
Bruno and company have to very rapidly come up with proof of the ability to set up a buffer zone between the two sides of the border, to stop a war.
5 out of 5
http://www.asimovs.com/_issue_0805/DarkINtegers.shtml
Number of words : 16300
Percent of complex words : 11.9
Average syllables per word : 1.5
Average words per sentence : 22.9
READABILITY INDICES
Fog : 13.9
Flesch : 53.6
Flesch-Kincaid : 11.5
PEOPLE
Bruno Costanzo
Mathematical defect mapper and watcher.
Sam
Bruno's counterpart on the far side.
Alison Tierney
Bruno's friend and co-watcher.
Yuen
Alison's mentor.
Laura
Alison's daughter.
Tim Campbell
A number theory researcher working at Victoria University.
Kate
Bruno's girlfriend.
Machiavelli
Political theorist.
Gerard Hooft
Quantum mathematician.
Bridget
Campbell's wife, an organic chemist. Also a lecturer at Victoria University.
Richard Branson
English billionaire.
Brando
An actor.
Hedy Lamarr
An actress.
Genghis Khan
Mongol warlord.
ORGANISATIONS
Industrial Algebra
Company that wants to exploit Bruno and Alison's discovery.
Victoria University
In Wellington.
JJJ
Radio station, focused on new music for the young.
PLACES
Sydney
Australian city.
Shanghai
Major city in China.
Zurich
Where Alison lives.
West Ryde
Suburb of Sydney.
Tasman
Sea between Australia and New Zealand.
Blue Mountains
Outside Sydney.
Penrith
Sydney suburb.
MEDIA
The West Wing
American tv show.
Dick Tracy
Comic strip detective.
Dr Strangelove
Bomb movie.
CONCEPTS
Planck scale
Very, very small. Physics measurement.
Dark Integers
A type definition of 4096 bits.
Fields Medal
Prize awarded to young mathematicians.
VEHICLES
Sputnik
Russian spacecraft.
PLOT
Ten years after Luminous, Bruno, Alison and an ill Yuen work to keep a detente with the far side, who are led by Sam as their contact.
When a New Zealand number theorist makes a discovery on his own, this threatens cordial relations, and Bruno has to scramble to get him onside. As he doesn't want to kill him, being Alison's other option.
Further work of Campbell's allows him to map the other side, showing their space is different, they are in a different solar system, and have different life.
Conflict starts, and changing mathematical axioms can do bad things, like crash markets and make planes fall out of the sky, killing many people.
Bruno and company have to very rapidly come up with proof of the ability to set up a buffer zone between the two sides of the border, to stop a war.
5 out of 5
http://www.asimovs.com/_issue_0805/DarkINtegers.shtml
Industrial Algebra : Dark Integers - Greg Egan
Company that wants to exploit Bruno and Alison's discovery.
3 out of 5
3 out of 5
Bridget : Dark Integers - Greg Egan
Campbell's wife, an organic chemist. Also a lecturer at Victoria University.
3 out of 5
3 out of 5
Tim Campbell : Dark Integers - Greg Egan
A number theory researcher working at Victoria University.
3.5 out of 5
3.5 out of 5
Luminous - Greg Egan
Number of words : 12600
Percent of complex words : 13.1
Average syllables per word : 1.6
Average words per sentence : 15.3
READABILITY INDICES
Fog : 11.4
Flesch : 54.0
Flesch-Kincaid : 9.5
PEOPLE
Bruno
Alison's ex-lover and co-operator. Mapper of mathematical defects.
Alison
Bruno's ex-lover and co-operator. Has idea that mathematics might be wonkier than we think.
Julia and Ramesh
Friends of theirs.
Andrew Wiles
Princeton researcher.
Lu Xun
A writer.
Andy Warhol
Artist.
Mao
Chinese leader.
Pinochet
Chilean dictator.
Yuen Ting-fu
Alison's supervisor for her Ph.D. on advanced applications of ring theory.
Cantor
A famous mathematician.
PLACES
Shanghai
Large Chinese city.
Hotel Fleapit
In Shanghai.
Hanoi
Vietnamese city.
Yuyuan Bazaar
Market in Shanghai.
Helsinki
Finnish city.
Zurich
Swiss city.
TECHNOLOGY
Necrotrap
Implanted carrying technology that breaks if disconnected from the host's biology.
Luminous
Chinese supercomputer made of light.
Surgical grade tissue repair cream
Good for stopping bleeding.
CONCEPTS
Mandarin
Chinese dialect.
Fermat's Last Theorem
No three positive integers a , b, and c can satisfy the equation an + bn = cn for any integer value of n.
Platonist
Follower of Plato's ideas.
Big Bang
Universe creation event.
ORGANISATIONS
Industrial Algebra
Aggressive UK IT company that wants their secrets.
Star TV
International Asian broadcaster.
Fu-tan University
Where Alison studied ring theory.
Exxon
Large corporation.
McDonnell-Douglas
Large corporation.
People's Institute for Advanced Optical Engineering
In Minhang. Houses Luminous and Yuen works there.
RACES
Han
A Chinese race that Bruno looks nothing like.
Australopithecus
Early human ancestor.
MEDIA
1984
Science fiction novel by George Orwell.
Winston Smith
Major character in 1984.
ANIMALS
Sea-urchin
Small, shiny ball-shaped ocean creature.
PLOT
Bruno wakes, having been found by an agent, but their precautions defeat her.
In June 1994, his fellow student Alison and he had a discussion, where she said:
"You're claiming that . . . mathematics might be strewn with primordial defects in consistency? Like space might be strewn with cosmic strings?"
"Exactly." She stared back at me, feigning nonchalance. "If space-time doesn't join up with itself smoothly, everywhere . . . why should mathematical logic?"
Which led to them researching such defects with success, and to agents of IA wanting their secrets to use in financial manipulations.
To further their work they manage to obtain some time on the most advanced computer in the world, thanks to Alison's old supervisor. They are quite shocked to find that what they are doing is being resisted - and stunned when they are contacted with information from this far side realm.
5 out of 5
http://www.fictionwise.com/ebooks/b974/Luminous/Greg-Egan/?
Percent of complex words : 13.1
Average syllables per word : 1.6
Average words per sentence : 15.3
READABILITY INDICES
Fog : 11.4
Flesch : 54.0
Flesch-Kincaid : 9.5
PEOPLE
Bruno
Alison's ex-lover and co-operator. Mapper of mathematical defects.
Alison
Bruno's ex-lover and co-operator. Has idea that mathematics might be wonkier than we think.
Julia and Ramesh
Friends of theirs.
Andrew Wiles
Princeton researcher.
Lu Xun
A writer.
Andy Warhol
Artist.
Mao
Chinese leader.
Pinochet
Chilean dictator.
Yuen Ting-fu
Alison's supervisor for her Ph.D. on advanced applications of ring theory.
Cantor
A famous mathematician.
PLACES
Shanghai
Large Chinese city.
Hotel Fleapit
In Shanghai.
Hanoi
Vietnamese city.
Yuyuan Bazaar
Market in Shanghai.
Helsinki
Finnish city.
Zurich
Swiss city.
TECHNOLOGY
Necrotrap
Implanted carrying technology that breaks if disconnected from the host's biology.
Luminous
Chinese supercomputer made of light.
Surgical grade tissue repair cream
Good for stopping bleeding.
CONCEPTS
Mandarin
Chinese dialect.
Fermat's Last Theorem
No three positive integers a , b, and c can satisfy the equation an + bn = cn for any integer value of n.
Platonist
Follower of Plato's ideas.
Big Bang
Universe creation event.
ORGANISATIONS
Industrial Algebra
Aggressive UK IT company that wants their secrets.
Star TV
International Asian broadcaster.
Fu-tan University
Where Alison studied ring theory.
Exxon
Large corporation.
McDonnell-Douglas
Large corporation.
People's Institute for Advanced Optical Engineering
In Minhang. Houses Luminous and Yuen works there.
RACES
Han
A Chinese race that Bruno looks nothing like.
Australopithecus
Early human ancestor.
MEDIA
1984
Science fiction novel by George Orwell.
Winston Smith
Major character in 1984.
ANIMALS
Sea-urchin
Small, shiny ball-shaped ocean creature.
PLOT
Bruno wakes, having been found by an agent, but their precautions defeat her.
In June 1994, his fellow student Alison and he had a discussion, where she said:
"You're claiming that . . . mathematics might be strewn with primordial defects in consistency? Like space might be strewn with cosmic strings?"
"Exactly." She stared back at me, feigning nonchalance. "If space-time doesn't join up with itself smoothly, everywhere . . . why should mathematical logic?"
Which led to them researching such defects with success, and to agents of IA wanting their secrets to use in financial manipulations.
To further their work they manage to obtain some time on the most advanced computer in the world, thanks to Alison's old supervisor. They are quite shocked to find that what they are doing is being resisted - and stunned when they are contacted with information from this far side realm.
5 out of 5
http://www.fictionwise.com/ebooks/b974/Luminous/Greg-Egan/?
People's Institute for Advanced Optical Engineering : Luminous - Greg Egan
In Minhang. Houses Luminous and Yuen works there.
4 out of 5
4 out of 5
Industrial Algebra : Luminous - Greg Egan
Aggressive UK IT company that wants their secrets.
4 out of 5
4 out of 5
Fermat's Last Theorem : Luminous - Greg Egan
No three positive integers a , b, and c can satisfy the equation an + bn = cn for any integer value of n.
4 out of 5
4 out of 5
Necrotrap : Luminous - Greg Egan
Implanted carrying technology that breaks if disconnected from the host's biology.
4 out of 5
4 out of 5
Yuen Ting-fu : Luminous - Greg Egan
Alison's supervisor for her Ph.D. on advanced applications of ring theory.
4.5 out of 5
4.5 out of 5
Alison : Luminous - Greg Egan
Bruno's ex-lover and co-operator. Has idea that mathematics might be wonkier than we think.
4.5 out of 5
4.5 out of 5
Bruno : Luminous - Greg Egan
Alison's ex-lover and co-operator. Mapper of mathematical defects.
5 out of 5
5 out of 5
Friday, June 11, 2010
Escher Applet - Greg Egan
"Escher is inspired by the conflicting orientation cues that are used throughout the artwork of M.C. Escher. The technique of projecting selected faces from hypercubes is adapted from deBruijn's method for quasiperiodic tilings, which is illustrated in the deBruijn applet."
4 out of 5
http://www.gregegan.net/APPLETS/02/02.html
4 out of 5
http://www.gregegan.net/APPLETS/02/02.html
SO (3) - Greg Egan
"SO(3) is a schematic of the group of rotations in three dimensions. Any rotation can be specified by a vector pointing along the axis of rotation, with a length equal to the amount of rotation; using this correspondence, each cube here has been rotated by its own position vector, relative to the central cube. The group is drawn as a sphere — with a wedge removed to reveal the interior — but the true topology identifies opposite points on the surface, which represent rotations of 180° around opposite axes."
3.5 out of 5
http://www.gregegan.net/APPLETS/01/01.html
3.5 out of 5
http://www.gregegan.net/APPLETS/01/01.html
Spin Networks Technical Notes - Greg Egan
"The effect of parallel-transporting vectors along a path, viewed as a linear map between the tangent spaces at the beginning and end of the path, is known as the holonomy for that path, and will always take the form of some rotation, R. The family of geometries for which the applet evaluates each spin network is characterised by the following simple rule: parallel transport along a straight line from the point (x0,y0,z0) to the point (x1,y1,z1) rotates vectors around the axis a, by an angle equal to the magnitude of a, where:
a = κ (y0 z1 – z0 y1, z0 x1 – x0 z1, x0 y1 – y0 x1)"
5 out of 5
http://www.gregegan.net/SCHILD/Spin/SpinNotes.html
a = κ (y0 z1 – z0 y1, z0 x1 – x0 z1, x0 y1 – y0 x1)"
5 out of 5
http://www.gregegan.net/SCHILD/Spin/SpinNotes.html
Quantum Mechanics and Quarantine - Greg Egan
"This essay contains spoilers for my novel Quarantine. If you haven't read it, and have any intention of doing so, you will probably enjoy it more if you read it before you read this essay.
Quantum mechanics was born early in the twentieth century as a way of dealing with some puzzling aspects of the behaviour of light and matter. In the process of constructing theories to make sense of what seemed at first to be a few niggling loose ends in classical physics, a revolution was started that has led to powerful, detailed, predictive models for describing almost every aspect of the microscopic world. However, while quantum mechanics has been an incontrovertible success, its ultimate implications remain a matter of controversy. We know how to calculate the behaviour of nuclei and molecules, lasers and logic gates, but there is still no consensus as to what quantum mechanics tells us about the fundamental nature of reality. Classical mechanics assumed that reality was more or less the way it appeared to be from everyday experience. Quantum mechanics shows that it isn't, but there is still no firm consensus as to exactly what should replace the classical view.
My 1992 novel Quarantine centred on a tongue-in-cheek, science-fictional resolution of that controversy, with a hypothesis that was chosen solely for its technological and existential ramifications, not because I considered it plausible. I said as much in interviews at the time. However, the world is full of misinformation about quantum mechanics, and while nobody would mistake Quarantine for a textbook on the subject, over the years I've often looked back and winced at some scientific flaws in the novel that go beyond the mere implausibility of its central premise."
4.5 out of 5
http://www.gregegan.net/QUARANTINE/QM/QM.html
Quantum mechanics was born early in the twentieth century as a way of dealing with some puzzling aspects of the behaviour of light and matter. In the process of constructing theories to make sense of what seemed at first to be a few niggling loose ends in classical physics, a revolution was started that has led to powerful, detailed, predictive models for describing almost every aspect of the microscopic world. However, while quantum mechanics has been an incontrovertible success, its ultimate implications remain a matter of controversy. We know how to calculate the behaviour of nuclei and molecules, lasers and logic gates, but there is still no consensus as to what quantum mechanics tells us about the fundamental nature of reality. Classical mechanics assumed that reality was more or less the way it appeared to be from everyday experience. Quantum mechanics shows that it isn't, but there is still no firm consensus as to exactly what should replace the classical view.
My 1992 novel Quarantine centred on a tongue-in-cheek, science-fictional resolution of that controversy, with a hypothesis that was chosen solely for its technological and existential ramifications, not because I considered it plausible. I said as much in interviews at the time. However, the world is full of misinformation about quantum mechanics, and while nobody would mistake Quarantine for a textbook on the subject, over the years I've often looked back and winced at some scientific flaws in the novel that go beyond the mere implausibility of its central premise."
4.5 out of 5
http://www.gregegan.net/QUARANTINE/QM/QM.html
Quantum Soccer - Technical Notes
"The energy eigenfunctions of Schrödinger's equation for a two-dimensional square-well potential with infinitely high walls are:
φn,p(x,y,t) = (2/√LM) sin(nÏ€x/L) sin(pÏ€y/M) exp(–2Ï€iEn,pt/h) (1)
where L and M are the dimensions of the well in the x- and y-directions (x and y being zero at one of the corners of the well), n and p are integers greater than or equal to 1, specifying the number of half-wavelengths that fit across the well in each direction, h is Planck's constant, and En,p is the energy of the eigenfunction, given by:
En,p = (h2/8m)((n/L)2 + (p/M)2)"
5 out of 5
http://www.gregegan.net/BORDER/Soccer/SoccerNotes.html
φn,p(x,y,t) = (2/√LM) sin(nÏ€x/L) sin(pÏ€y/M) exp(–2Ï€iEn,pt/h) (1)
where L and M are the dimensions of the well in the x- and y-directions (x and y being zero at one of the corners of the well), n and p are integers greater than or equal to 1, specifying the number of half-wavelengths that fit across the well in each direction, h is Planck's constant, and En,p is the energy of the eigenfunction, given by:
En,p = (h2/8m)((n/L)2 + (p/M)2)"
5 out of 5
http://www.gregegan.net/BORDER/Soccer/SoccerNotes.html
Partition of Unity Detailed - Greg Egan
"The surface of a hypersphere in 5 dimensions can be described by the equation:
x2 + y2 + z2 + u2 + w2 = R2 (1)
where x,y,z,u,w are the 5 spatial coordinates, and the origin of the coordinate system lies at the centre of the hypersphere.
Suppose this hypersphere is rotating as a rigid body. In general (in any number of dimensions) the velocity v of any point of a rotating body is given by the product of the body's angular velocity matrix, Ω, with the vector for the point in question, r.
v = Ω r"
5 out of 5
http://www.gregegan.net/DIASPORA/17/17det.html
x2 + y2 + z2 + u2 + w2 = R2 (1)
where x,y,z,u,w are the 5 spatial coordinates, and the origin of the coordinate system lies at the centre of the hypersphere.
Suppose this hypersphere is rotating as a rigid body. In general (in any number of dimensions) the velocity v of any point of a rotating body is given by the product of the body's angular velocity matrix, Ω, with the vector for the point in question, r.
v = Ω r"
5 out of 5
http://www.gregegan.net/DIASPORA/17/17det.html
Truth Mining Detailed - Greg Egan
"The standard way to embed a torus in 3 dimensions is:
(x, y, z) = ((a – b cos B) cos A, (a – b cos B) sin A, b sin B) (1)
where a and b are the major and minor radii of the torus, and A and B are angles that vary from 0 to 2 π radians. This is shown below left."
5 out of 5
http://www.gregegan.net/DIASPORA/02/02det.html
(x, y, z) = ((a – b cos B) cos A, (a – b cos B) sin A, b sin B) (1)
where a and b are the major and minor radii of the torus, and A and B are angles that vary from 0 to 2 π radians. This is shown below left."
5 out of 5
http://www.gregegan.net/DIASPORA/02/02det.html
Lizard Heart Details - Greg Egan
"The relationship between the orbital period, T, and the separation between the neutron stars, a, is given by Kepler's Law: the period squared is proportional to the separation cubed.
T2 = (4Ï€2/GM) a3
where M = m1+m2 is the combined mass of the two stars, and G is the universal gravitational constant.
The total power being radiated in gravitational waves is inversely proportional to the fifth power of the separation."
5 out of 5
http://www.gregegan.net/DIASPORA/04/04det.html
T2 = (4Ï€2/GM) a3
where M = m1+m2 is the combined mass of the two stars, and G is the universal gravitational constant.
The total power being radiated in gravitational waves is inversely proportional to the fifth power of the separation."
5 out of 5
http://www.gregegan.net/DIASPORA/04/04det.html
Orbits and Tidal Accelerations Detailed - Greg Egan
"Consider a space station moving in a circular orbit around some massive body (a planet, a star, or perhaps a black hole), “tidally locked” so that it always keeps the same face towards whatever it's orbiting. At the centre of the station objects will be weightless, but away from the centre how will they move? Or if they are kept from moving by appropriately oriented “floors”, what weight will they experience? These seem like very simple questions, but it turns out that they involve a lot of interesting physics, and can even reveal whether or not the station is in an orbit where relativistic effects come into play, without the need to make observations of anything outside the station itself."
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Orbits/OrbitsDetailed.html
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Orbits/OrbitsDetailed.html
Deriving Part of the Kerr Geometry - Greg Egan
"In Chapter 20 of Incandescence, the Splinterites derive a spacetime geometry that is symmetrical under rotations around a single axis. This is a much harder feat than the case of a geometry that has spherical symmetry. In our own history, the spherically symmetrical case was solved by Schwarzschild in 1915, but the Kerr spacetime, with axial symmetry, was not found until 1963! The Kerr solution describes a black hole formed by the collapse of a rotating star, and the imprint of the star's angular momentum can be seen in the geometry surrounding the hole.
The spherically symmetrical problem is essentially one-dimensional; everything depends only upon r, the radial coordinate, and so it boils down to solving equations for functions of one variable, known as ordinary differential equations. In the axially symmetrical version, the geometry depends not only upon r, but also upon the “latitude” of each point, which measures its relationship to the axis of symmetry. So we're forced to solve equations for functions of two variables: partial differential equations. These are not so simple to deal with."
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Schwarzschild/X.html
The spherically symmetrical problem is essentially one-dimensional; everything depends only upon r, the radial coordinate, and so it boils down to solving equations for functions of one variable, known as ordinary differential equations. In the axially symmetrical version, the geometry depends not only upon r, but also upon the “latitude” of each point, which measures its relationship to the axis of symmetry. So we're forced to solve equations for functions of two variables: partial differential equations. These are not so simple to deal with."
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Schwarzschild/X.html
Deriving Newtonian Spacetime Geometry - Greg Egan
"In Chapter 12 of Incandescence, the Splinterites succeed in deriving a possible geometry for the spacetime they inhabit. They come up with the simplest possible geometry that conforms to Zak's principle (that the sum of the three perpendicular “weights”, or tidal accelerations, is zero, after the effects of spin have been removed) while explaining the fact that the ratio of the garm-sard weight to the shomal-junub weight is less than three.
Before reaching that solution, though, they make a couple of false starts. Initially, they assume that there is a notion of universal time, and when they look for a connection that is consistent with that assumption, they end up deriving a spacetime geometry where the ratio of weights is always precisely three."
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Schwarzschild/W.html
Before reaching that solution, though, they make a couple of false starts. Initially, they assume that there is a notion of universal time, and when they look for a connection that is consistent with that assumption, they end up deriving a spacetime geometry where the ratio of weights is always precisely three."
5 out of 5
http://www.gregegan.net/INCANDESCENCE/Schwarzschild/W.html
Decoherence Technical Notes - Greg Egan
" * Quantum and Classical Behaviour
* Pure States
* Superpositions
* Mixtures and Density Matrices
* Subsystems
* How Entanglement Hides Quantum Interference"
5 out of 5
http://www.gregegan.net/SCHILD/Decoherence/DecoherenceNotes.html
* Pure States
* Superpositions
* Mixtures and Density Matrices
* Subsystems
* How Entanglement Hides Quantum Interference"
5 out of 5
http://www.gregegan.net/SCHILD/Decoherence/DecoherenceNotes.html
Cordelia's Tour Technical Notes - Greg Egan
" * Preliminaries
* (A) Blueshift outside the hole, for a stationary observer
* (B) Red- and blueshifts inside the hole, for a stationary observer
* (C) Red- and blueshifts for a free-falling observer
* (D) Apparent position and brightness of stars"
5 out of 5
http://www.gregegan.net/PLANCK/Tour/TourNotes.html
* (A) Blueshift outside the hole, for a stationary observer
* (B) Red- and blueshifts inside the hole, for a stationary observer
* (C) Red- and blueshifts for a free-falling observer
* (D) Apparent position and brightness of stars"
5 out of 5
http://www.gregegan.net/PLANCK/Tour/TourNotes.html
Newtonian Hoop Applet - Greg Egan
"This applet models a Newtonian rotating elastic hoop as a polygon with point masses at the vertices, and edges consisting of elastic material; the edges are assumed to have negligible mass, always to be straight line segments, and to obey Hooke's law exactly. (Note that only one in every 10 vertices is marked, rather than all of them; this gives a clearer sense of the motion of the hoop by avoiding “strobe” effects.)"
4 out of 5
http://www.gregegan.net/SCIENCE/Rings/SimpleHoopApplet.html
4 out of 5
http://www.gregegan.net/SCIENCE/Rings/SimpleHoopApplet.html
Rotating Elastic Rings, Disks and Hoops - Greg Egan
"In the history of special relativity, numerous thought experiments have involved rotating rings, disks and hoops. One striking feature of a uniformly rotating body in special relativity is that a family of observers who are tied to the body — and hence in a colloquial sense might seem to be “at rest” relative to each other — nonetheless can't synchronise their clocks, or agree on a shared definition of how spacetime should be split up into space and time. The reason, of course, is that the forces that maintain the body's shape are accelerating each point of the body, and the magnitude and direction of the acceleration varies from point to point. Unlike the situation where observers are tied to a body undergoing uniform linear motion, there is no way to slice up spacetime into hypersurfaces that are everywhere orthogonal to the observers' world lines.
The purpose of this web page is to give a very simple model for an annular ring of elastic material rotating with a constant angular velocity in the plane of the ring. If the inner radius of the annulus is zero, we have a disk; if the inner and outer radii are equal, we have a hoop. We will assume that the vertical thickness of the ring is zero, making the problem essentially one in two spatial dimensions, plus time."
5 out of 5
http://www.gregegan.net/SCIENCE/Rings/Rings.html
The purpose of this web page is to give a very simple model for an annular ring of elastic material rotating with a constant angular velocity in the plane of the ring. If the inner radius of the annulus is zero, we have a disk; if the inner and outer radii are equal, we have a hoop. We will assume that the vertical thickness of the ring is zero, making the problem essentially one in two spatial dimensions, plus time."
5 out of 5
http://www.gregegan.net/SCIENCE/Rings/Rings.html
Relativistic Elasticity - Greg Egan
"In thought experiments in special relativity, when a rocket engine pushes on the rear of a spacecraft, or a tether is dragged behind an accelerating craft, assuming that these extended objects respond to the forces on them instantly and without deformation can lead to confusion and apparent paradoxes. The idealisation of a rigid body, which can often be useful in Newtonian physics, is generally no longer applicable, since it corresponds to an assumption of an infinite speed of sound within the body, in violation of relativistic causality.
In many cases, a qualitative understanding that perfectly rigid motion will be the exception rather than the rule in special relativity is enough to avoid the pitfalls. At other times, though, it can be useful to have a simple, quantitative model that deals with elastic deformation in a way that is consistent with special relativity.
The purpose of this page is to describe such a model of relativistic elasticity. We will restrict ourselves to the simplest possible situation: one-dimensional hyperelastic bodies. By “hyperelastic”, we mean the body will obey Hooke's law, which states that any change in length of a portion of the body (compared to its unstretched, or “relaxed” length) will be proportional to the tension to which it is subjected. For any real material, Hooke's law is just an approximation which holds over a limited range of tension and compression. However, for the sake of producing a (reasonably) mathematically tractable model, we will treat it as an exact law which holds up to the point where the material breaks."
5 out of 5
http://www.gregegan.net/SCIENCE/Rindler/SimpleElasticity.html
In many cases, a qualitative understanding that perfectly rigid motion will be the exception rather than the rule in special relativity is enough to avoid the pitfalls. At other times, though, it can be useful to have a simple, quantitative model that deals with elastic deformation in a way that is consistent with special relativity.
The purpose of this page is to describe such a model of relativistic elasticity. We will restrict ourselves to the simplest possible situation: one-dimensional hyperelastic bodies. By “hyperelastic”, we mean the body will obey Hooke's law, which states that any change in length of a portion of the body (compared to its unstretched, or “relaxed” length) will be proportional to the tension to which it is subjected. For any real material, Hooke's law is just an approximation which holds over a limited range of tension and compression. However, for the sake of producing a (reasonably) mathematically tractable model, we will treat it as an exact law which holds up to the point where the material breaks."
5 out of 5
http://www.gregegan.net/SCIENCE/Rindler/SimpleElasticity.html
Wednesday, June 9, 2010
The Cutie - Greg Egan
Short Story
Number of words : 4400
Percent of complex words : 10.4
Average syllables per word : 1.5
Average words per sentence : 19.3
READABILITY INDICES
Fog : 11.9
Flesch : 58.0
Flesch-Kincaid : 10.0
PEOPLE
Diane
A woman who doesn't want a kid.
Frank
A man who does want a kid.
Bach
A composer.
Angel
The Cutie.
ORGANISATIONS
EFT
Manufacturers of the Cutie kit.
TECHNOLOGY
Cabbage Patch Doll
A toy.
Video Baby
A toy.
Computer Crib
A toy.
Black Box
Part of the system used for making and monitoring Cuties.
CONCEPT
Cutie
A child substitute made by genetic modification of the donor's DNS. Stupider than puppies.
PLOT
A man who really wants a child cannot find a willing partner and decides to carry a Cutie to term. A genetically modified person that is made to look like a cute baby, but to be dumb and not live long enough to make it past this stage.
4 out of 5
Number of words : 4400
Percent of complex words : 10.4
Average syllables per word : 1.5
Average words per sentence : 19.3
READABILITY INDICES
Fog : 11.9
Flesch : 58.0
Flesch-Kincaid : 10.0
PEOPLE
Diane
A woman who doesn't want a kid.
Frank
A man who does want a kid.
Bach
A composer.
Angel
The Cutie.
ORGANISATIONS
EFT
Manufacturers of the Cutie kit.
TECHNOLOGY
Cabbage Patch Doll
A toy.
Video Baby
A toy.
Computer Crib
A toy.
Black Box
Part of the system used for making and monitoring Cuties.
CONCEPT
Cutie
A child substitute made by genetic modification of the donor's DNS. Stupider than puppies.
PLOT
A man who really wants a child cannot find a willing partner and decides to carry a Cutie to term. A genetically modified person that is made to look like a cute baby, but to be dumb and not live long enough to make it past this stage.
4 out of 5
Cutie : The Cutie - Greg Egan
A child substitute made by genetic modification of the donor's DNS. Stupider than puppies.
4 out of 5
4 out of 5
Black Box : The Cutie - Greg Egan
Part of the system used for making and monitoring Cuties.
3.5 out of 5
3.5 out of 5
Crystal Nights - Greg Egan
Novelette
Number of words : 9800
Percent of complex words : 11.5
Average syllables per word : 1.6
Average words per sentence : 20.7
READABILITY INDICES
Fog : 12.9
Flesch : 54.4
Flesch-Kincaid : 10.8
PEOPLE
Daniel Cliff
A billionaire that wants to do AI research.
Julie Denghani
The best AI researcher of her generation.
Lucien Crace
A scientist for Cliff. Has a doctorate in genetic programming.
Sunil Gupta
Multimedia search engine entrepreneur.
Angela Lindstrom
Creator of AfterLife dying client avatar software.
Primo
A Phite who communicates with Daniel and gives him insight.
TECHNOLOGY
FLOPS rating
Measure of processing power for a computer.
Lattice QCD
Is a well established non-perturbative approach to solving the quantum chromodynamics theory of quarks and gluons.
AI
Artificial Intelligence.
Crystal
A photonic optical computer. Extremely expensive.
Thought Police
Phite monitoring software.
The Play Pen
Vacuum chamber containing an atomic force microscope with fifty thousand independently movable tips, arrays of solid-state lasers and photodetectors, and thousands of micro-wells stocked with samples of all the stable chemical elements.
CONCEPTS
Pascal's Wager
The name given to an argument due to Blaise Pascal for believing, or for at least taking steps to believe, in God.
Project Sapphire
Term for the Phite world experiment.
Higgs field
Theoretical field that permeates space and endows all elementary subatomic particles with mass through its interactions with them. Discovered by the Phites.
Big Bang
Universe creation event.
Matrioshka Brain
Hypothetical megastructure, based on the Dyson sphere, of immense computational capacity.
ORGANISATIONS
WiddulHands.com
Made Cliff his first billion in Social Networking for infants.
Foodexcuse.com
Where Crace made his money. Web tech that finds reasons to eat bad stuff.
Transhumanists
An international intellectual and cultural movement supporting the use of science and technology to improve human mental and physical characteristics and capacities.
Lunar Project
Phite research operation.
RACES
Phites
A created race, crablike, used in Cliff's evolutionary intelligence experiments.
PLOT
Daniel Cliff is a technology billionaire who wants a research advantage. He thinks conventional AI research is a dead end, and decides to embark on a genetic programming evolution experiment. Thanks to his investment in advanced supercomputing technology he has the poewr to run these cycles of life far faster than time passes in the real world.
Various successes and failures happen, but he pushes his creations to outstrip humans in the area of physics. They discover the Higgs field and bootstrap themselves out of their computing prison, leaving him severely burned in the process, with his rivals catching up to him.
5 out of 5
http://ttapress.com/553/crystal-nights-by-greg-egan/
Number of words : 9800
Percent of complex words : 11.5
Average syllables per word : 1.6
Average words per sentence : 20.7
READABILITY INDICES
Fog : 12.9
Flesch : 54.4
Flesch-Kincaid : 10.8
PEOPLE
Daniel Cliff
A billionaire that wants to do AI research.
Julie Denghani
The best AI researcher of her generation.
Lucien Crace
A scientist for Cliff. Has a doctorate in genetic programming.
Sunil Gupta
Multimedia search engine entrepreneur.
Angela Lindstrom
Creator of AfterLife dying client avatar software.
Primo
A Phite who communicates with Daniel and gives him insight.
TECHNOLOGY
FLOPS rating
Measure of processing power for a computer.
Lattice QCD
Is a well established non-perturbative approach to solving the quantum chromodynamics theory of quarks and gluons.
AI
Artificial Intelligence.
Crystal
A photonic optical computer. Extremely expensive.
Thought Police
Phite monitoring software.
The Play Pen
Vacuum chamber containing an atomic force microscope with fifty thousand independently movable tips, arrays of solid-state lasers and photodetectors, and thousands of micro-wells stocked with samples of all the stable chemical elements.
CONCEPTS
Pascal's Wager
The name given to an argument due to Blaise Pascal for believing, or for at least taking steps to believe, in God.
Project Sapphire
Term for the Phite world experiment.
Higgs field
Theoretical field that permeates space and endows all elementary subatomic particles with mass through its interactions with them. Discovered by the Phites.
Big Bang
Universe creation event.
Matrioshka Brain
Hypothetical megastructure, based on the Dyson sphere, of immense computational capacity.
ORGANISATIONS
WiddulHands.com
Made Cliff his first billion in Social Networking for infants.
Foodexcuse.com
Where Crace made his money. Web tech that finds reasons to eat bad stuff.
Transhumanists
An international intellectual and cultural movement supporting the use of science and technology to improve human mental and physical characteristics and capacities.
Lunar Project
Phite research operation.
RACES
Phites
A created race, crablike, used in Cliff's evolutionary intelligence experiments.
PLOT
Daniel Cliff is a technology billionaire who wants a research advantage. He thinks conventional AI research is a dead end, and decides to embark on a genetic programming evolution experiment. Thanks to his investment in advanced supercomputing technology he has the poewr to run these cycles of life far faster than time passes in the real world.
Various successes and failures happen, but he pushes his creations to outstrip humans in the area of physics. They discover the Higgs field and bootstrap themselves out of their computing prison, leaving him severely burned in the process, with his rivals catching up to him.
5 out of 5
http://ttapress.com/553/crystal-nights-by-greg-egan/
Phites : Crystal Nights - Greg Egan
A created race, crablike, used in Cliff's evolutionary intelligence experiments.
4 out of 5
4 out of 5
Transhumanists : Crystal Nights - Greg Egan
An international intellectual and cultural movement supporting the use of science and technology to improve human mental and physical characteristics and capacities.
3 out of 5
3 out of 5
Foodexcuse.com : Crystal Nights - Greg Egan
Where Crace made his money. Web tech that finds reasons to eat bad stuff.
3.5 out of 5
3.5 out of 5
WiddulHands.com : Crystal Nights - Greg Egan
Made Cliff his first billion in Social Networking for infants.
3.5 out of 5
3.5 out of 5
Matrioshka Brain : Crystal Nights - Greg Egan
Hypothetical megastructure, based on the Dyson sphere, of immense computational capacity.
3 out of 5
3 out of 5
Higgs field : Crystal Nights - Greg Egan
Theoretical field that permeates space and endows all elementary subatomic particles with mass through its interactions with them. Discovered by the Phites.
4 out of 5
4 out of 5
Pascal's Wager : Crystal Nights - Greg Egan
The name given to an argument due to Blaise Pascal for believing, or for at least taking steps to believe, in God.
3 out of 5
3 out of 5
The Play Pen : Crystal Nights - Greg Egan
Vacuum chamber containing an atomic force microscope with fifty thousand independently movable tips, arrays of solid-state lasers and photodetectors, and thousands of micro-wells stocked with samples of all the stable chemical elements.
4 out of 5
4 out of 5
Lattice QCD : Crystal Nights - Greg Egan
Is a well established non-perturbative approach to solving the quantum chromodynamics theory of quarks and gluons.
4 out of 5
4 out of 5
Primo : Crystal Nights - Greg Egan
A Phite who communicates with Daniel and gives him insight.
3.5 out of 5
3.5 out of 5
Angela Lindstrom : Crystal Nights - Greg Egan
Creator of AfterLife dying client avatar software.
3 out of 5
3 out of 5
Lucien Crace : Crystal Nights - Greg Egan
A scientist for Cliff. Has a doctorate in genetic programming.
3.5 out of 5
3.5 out of 5
Incandescence 1 - Greg Egan
"“Which makes it no less true,” Rakesh protested. “Our ancestors have sucked the Milky Way dry. We were born too late; there's nothing left for us.”
“Only several billion other galaxies,” Parantham observed mildly. She smiled; her position on this subject had barely shifted since Rakesh had met her, but for her it was still a worthwhile debate, not the empty ritual it had become for Csi.
“Containing what?” Rakesh countered. “Probably more or less the same kinds of worlds and civilisations as our own. Probably nothing that would not be a hideous anticlimax, after travelling such a distance.” A few thousand intrepid fools had, in fact, set out for Andromeda, with no guarantee that the spore packages they'd sent in advance would survive the two-million-light-year journey and construct receivers for them."
4 out of 5
http://www.gregegan.net/INCANDESCENCE/01/IncandescenceExcerpt.html
“Only several billion other galaxies,” Parantham observed mildly. She smiled; her position on this subject had barely shifted since Rakesh had met her, but for her it was still a worthwhile debate, not the empty ritual it had become for Csi.
“Containing what?” Rakesh countered. “Probably more or less the same kinds of worlds and civilisations as our own. Probably nothing that would not be a hideous anticlimax, after travelling such a distance.” A few thousand intrepid fools had, in fact, set out for Andromeda, with no guarantee that the spore packages they'd sent in advance would survive the two-million-light-year journey and construct receivers for them."
4 out of 5
http://www.gregegan.net/INCANDESCENCE/01/IncandescenceExcerpt.html
Schild's Ladder 1 - Greg Egan
"“The danger doesn't seem real to me,” Yann admitted. “Viro is seventeen light-years away, and we can't be sure that this thing won't snuff itself out before it even grazes the shell of the Quietener. But I would like to know the general law that replaces the Sarumpaet rules. It's been twenty thousand years! It's about time we had some new physics.”
Cass turned to Bakim.
He shrugged. “What else are we going to do? Play charades?”
Cass was outnumbered, and she wanted to be swayed. She ached to get her hands on even the smallest piece of evidence that the disaster could be contained, and if they failed, it would still be the least morbid way to go out: struggling to the end to find a genuine cause for optimism.
But they were fooling themselves. In the few subjective minutes left to them, what hope did they have of achieving that?
She said simply, “We'll never make it. We'll test one hunch against the data, find it's wrong, and that will be it.”
Rainzi smiled as if she'd said something comically naïve. Before he spoke, Cass recalled what it was she had forgotten.
What it was she had become.
He said, “That's how it will seem for most of us. But that shouldn't be disheartening. Because every time we fail, we'll know that another version of ourselves will have tested another idea. There will always be a chance that one of them was right.”"
5 out of 5
http://www.gregegan.net/SCHILD/00/SchildExcerpt.html
Cass turned to Bakim.
He shrugged. “What else are we going to do? Play charades?”
Cass was outnumbered, and she wanted to be swayed. She ached to get her hands on even the smallest piece of evidence that the disaster could be contained, and if they failed, it would still be the least morbid way to go out: struggling to the end to find a genuine cause for optimism.
But they were fooling themselves. In the few subjective minutes left to them, what hope did they have of achieving that?
She said simply, “We'll never make it. We'll test one hunch against the data, find it's wrong, and that will be it.”
Rainzi smiled as if she'd said something comically naïve. Before he spoke, Cass recalled what it was she had forgotten.
What it was she had become.
He said, “That's how it will seem for most of us. But that shouldn't be disheartening. Because every time we fail, we'll know that another version of ourselves will have tested another idea. There will always be a chance that one of them was right.”"
5 out of 5
http://www.gregegan.net/SCHILD/00/SchildExcerpt.html
Permutation City Prologue - Greg Egan
"He closed his eyes again for a few seconds. When he opened them, the feeling was already less oppressive. No doubt it would pass; it seemed too bizarre a state of mind to be sustained for long. Certainly, none of the other Copies had reported anything similar … but then, none of them had volunteered much useful data at all. They'd just ranted abuse, whined about their plight, and then terminated themselves — all within fifteen (subjective) minutes of gaining consciousness.
And this one? How was he different from Copy number four? Three years older. More stubborn? More determined? More desperate for success? He'd believed so. If he hadn't felt more committed than ever — if he hadn't been convinced that he was, finally, prepared to see the whole thing through — he would never have gone ahead with the scan.
But now that he was “no longer” the flesh-and-blood Paul Durham — “no longer” the one who'd sit outside and watch the whole experiment from a safe distance — all of that determination seemed to have evaporated.
Suddenly he wondered: What makes me so sure that I'm not still flesh-and-blood? He laughed weakly, hardly daring to take the possibility seriously. His most recent memories seemed to be of lying on a trolley in the Landau Clinic, while technicians prepared him for the scan — on the face of it, a bad sign — but he'd been overwrought, and he'd spent so long psyching himself up for “this”, that perhaps he'd forgotten coming home, still hazy from the anaesthetic, crashing into bed, dreaming …
He muttered the password, “Abulafia” — and his last faint hope vanished, as a black-on-white square about a metre wide, covered in icons, appeared in midair in front of him."
5 out of 5
http://www.gregegan.net/PERMUTATION/Excerpt/PermutationExcerpt.html
And this one? How was he different from Copy number four? Three years older. More stubborn? More determined? More desperate for success? He'd believed so. If he hadn't felt more committed than ever — if he hadn't been convinced that he was, finally, prepared to see the whole thing through — he would never have gone ahead with the scan.
But now that he was “no longer” the flesh-and-blood Paul Durham — “no longer” the one who'd sit outside and watch the whole experiment from a safe distance — all of that determination seemed to have evaporated.
Suddenly he wondered: What makes me so sure that I'm not still flesh-and-blood? He laughed weakly, hardly daring to take the possibility seriously. His most recent memories seemed to be of lying on a trolley in the Landau Clinic, while technicians prepared him for the scan — on the face of it, a bad sign — but he'd been overwrought, and he'd spent so long psyching himself up for “this”, that perhaps he'd forgotten coming home, still hazy from the anaesthetic, crashing into bed, dreaming …
He muttered the password, “Abulafia” — and his last faint hope vanished, as a black-on-white square about a metre wide, covered in icons, appeared in midair in front of him."
5 out of 5
http://www.gregegan.net/PERMUTATION/Excerpt/PermutationExcerpt.html
Teranesia 1 - Greg Egan
"he island was too small for human habitation, and too far from the commonly travelled sea routes to serve as a navigation point, so the people of the Kai and Tanimbar Islands had never had reason to name it. The Javanese and Sumatran rulers who'd claimed tributes from the Spice Islands would have been oblivious to its existence, and Prabir had been unable to locate it on any Dutch or Portuguese chart that had been scanned and placed on the net. To the current Indonesian authorities it was a speck on the map of Maluku propinsi, included for the sake of completeness along with a thousand other uninhabited rocks. Prabir had realised the opportunity he was facing even before they'd left Calcutta, and he'd begun compiling a list of possibilities immediately, but it wasn't a decision he could make lightly. He'd been on the island for more than a year before he finally settled on a name for it.
He tried out the word on his classmates and friends before slipping it into a conversation with his parents. His father had smiled approvingly, but then had second thoughts.
“Why Greek? If you're not going to use a local language ... why not Bengali?”
Prabir had gazed back at him, puzzled. Names sounded dull if you understood them too easily. Why make do with a lame Big River, when you could have a majestic Rio Grande? But surely his father knew that. It was his example Prabir was following.
“The same reason you named the butterfly in Latin.”
His mother had laughed. “He's got you there!” And his father had relented, hoisting Prabir up into the air to be spun and tickled. “All right, all right! Teranesia!”"
3.5 out of 5
http://www.gregegan.net/TERANESIA/Excerpt/TeranesiaExcerpt.html
He tried out the word on his classmates and friends before slipping it into a conversation with his parents. His father had smiled approvingly, but then had second thoughts.
“Why Greek? If you're not going to use a local language ... why not Bengali?”
Prabir had gazed back at him, puzzled. Names sounded dull if you understood them too easily. Why make do with a lame Big River, when you could have a majestic Rio Grande? But surely his father knew that. It was his example Prabir was following.
“The same reason you named the butterfly in Latin.”
His mother had laughed. “He's got you there!” And his father had relented, hoisting Prabir up into the air to be spun and tickled. “All right, all right! Teranesia!”"
3.5 out of 5
http://www.gregegan.net/TERANESIA/Excerpt/TeranesiaExcerpt.html
Quarantine 1 - Greg Egan
"was eight years old when the stars went out.
November 15th, 2034, 8:11:05 to 8:27:42 GMT.
I didn't witness the circle of darkness, growing from the antisolar point like the mouth of a coal-black cosmic worm, gaping to swallow the world. On TV, yes, a hundred times, from a dozen locations — but on TV it looked like nothing but the cheapest of special effects (the satellite views all the more so; in glare-filtered shots, the “mouth” could be seen closing precisely behind the sun, an implausible symmetry, smacking of human contrivance).
I couldn't have seen it live, it was late afternoon in Perth — but the news reached us before sunset, and I stood on the balcony with my parents, in the dusk, waiting. When Venus appeared, and I pointed it out, my father lost his temper and sent me inside. I don't recall exactly what I said; I'm sure I knew the difference between stars and planets, but perhaps I made some childish joke. When I looked through my bedroom window — with a choice of smeared glass or dusty flyscreen — and saw, well, nothing, it was hard to be impressed. Later, when I finally caught an unimpeded view of the empty sky, I dutifully tried to feel awestruck, but failed. The sight was as unspectacular as an overcast night. It was only years later that I understood how terrified my parents must have been.
There were riots on Bubble Day across the planet, but the worst of the violence took place where people had seen the event with their own eyes — and that depended on a combination of longitude and weather. Night stretched from the western Pacific to Brazil, but cloud covered much of the Americas. There were clear skies over Peru, Colombia, Mexico and southern California — so Lima, Bogota, Mexico City and Los Angeles suffered accordingly. In New York, at eleven past three in the morning, it was bitterly cold and overcast — and the city was all but spared. Brasilia and Sao Paulo were saved by the light of dawn.
Disturbances in this country were minor; even on the east coast, sunset came too late, and apparently most Australians sat glued to their TVs all night, watching other people do the looting and burning. The End of the World was far too important to be happening anywhere but overseas. There were fewer deaths in Sydney than on the previous New Year's Eve."
4.5 out of 5
http://www.gregegan.net/QUARANTINE/Excerpt/QuarantineExcerpt.html
November 15th, 2034, 8:11:05 to 8:27:42 GMT.
I didn't witness the circle of darkness, growing from the antisolar point like the mouth of a coal-black cosmic worm, gaping to swallow the world. On TV, yes, a hundred times, from a dozen locations — but on TV it looked like nothing but the cheapest of special effects (the satellite views all the more so; in glare-filtered shots, the “mouth” could be seen closing precisely behind the sun, an implausible symmetry, smacking of human contrivance).
I couldn't have seen it live, it was late afternoon in Perth — but the news reached us before sunset, and I stood on the balcony with my parents, in the dusk, waiting. When Venus appeared, and I pointed it out, my father lost his temper and sent me inside. I don't recall exactly what I said; I'm sure I knew the difference between stars and planets, but perhaps I made some childish joke. When I looked through my bedroom window — with a choice of smeared glass or dusty flyscreen — and saw, well, nothing, it was hard to be impressed. Later, when I finally caught an unimpeded view of the empty sky, I dutifully tried to feel awestruck, but failed. The sight was as unspectacular as an overcast night. It was only years later that I understood how terrified my parents must have been.
There were riots on Bubble Day across the planet, but the worst of the violence took place where people had seen the event with their own eyes — and that depended on a combination of longitude and weather. Night stretched from the western Pacific to Brazil, but cloud covered much of the Americas. There were clear skies over Peru, Colombia, Mexico and southern California — so Lima, Bogota, Mexico City and Los Angeles suffered accordingly. In New York, at eleven past three in the morning, it was bitterly cold and overcast — and the city was all but spared. Brasilia and Sao Paulo were saved by the light of dawn.
Disturbances in this country were minor; even on the east coast, sunset came too late, and apparently most Australians sat glued to their TVs all night, watching other people do the looting and burning. The End of the World was far too important to be happening anywhere but overseas. There were fewer deaths in Sydney than on the previous New Year's Eve."
4.5 out of 5
http://www.gregegan.net/QUARANTINE/Excerpt/QuarantineExcerpt.html
The Dual Pythagoran Theorem - Greg Egan
"Much of the physics in the universe of Orthogonal can be understood as arising from fairly simple ideas in geometry. Although the physical consequences are sometimes very different from the consequences in our own universe, the geometry itself is still the same. This page describes one very simple example, which nonetheless underlies one of the most important scientific discoveries in the novel. It's also a result well worth knowing for its applications in our own world."
5 out of 5
http://www.gregegan.net/ORTHOGONAL/01/DualPythagorean.html
5 out of 5
http://www.gregegan.net/ORTHOGONAL/01/DualPythagorean.html
Tuesday, June 8, 2010
The Rindler Horizon - Greg Egan
"This web page was inspired by a discussion on the Usenet group sci.physics.research entitled “The Black Fishing Hole”, in which Edward Green asked for an account of precisely what would happen if someone lowered an object through a black hole's horizon on a fishing line. I gave a reply describing a slightly different, but related, scenario: that of a constantly accelerating observer in flat spacetime trailing an object behind them. Darryl McCullough made the connection explicit, pointing out that a first-order approximation of the Schwarzschild metric near a black hole's horizon gives a coordinate system for flat spacetime describing just such a class of observers."
5 out of 5
http://www.gregegan.net/SCIENCE/Rindler/RindlerHorizon.html
5 out of 5
http://www.gregegan.net/SCIENCE/Rindler/RindlerHorizon.html
Weak-field GR near the centre of a light planar mass - Greg Egan
"In Newtonian gravity, an infinite planar mass of uniform density σ produces a uniform gravitational field: at every point in space, test particles experience an acceleration of magnitude 2 π σ (in units where G=1), directed towards the plane and orthogonal to its surface.
Is there an analogous situation in General Relativity, and if so, in what ways does it depart from the Newtonian case? In fact there are at least two exact solutions of Einstein's equation that deserve to be called “infinite plane” solutions [1], but they both have exotic aspects (a cosmological constant, and relativistic pressures) that make them less similar to the Newtonian case than we might wish, if we're not interested in a strictly infinite plane for its own sake, but only in the mathematical simplicity that it yields."
5 out of 5
http://www.gregegan.net/SCIENCE/Planar/Planar.html
Is there an analogous situation in General Relativity, and if so, in what ways does it depart from the Newtonian case? In fact there are at least two exact solutions of Einstein's equation that deserve to be called “infinite plane” solutions [1], but they both have exotic aspects (a cosmological constant, and relativistic pressures) that make them less similar to the Newtonian case than we might wish, if we're not interested in a strictly infinite plane for its own sake, but only in the mathematical simplicity that it yields."
5 out of 5
http://www.gregegan.net/SCIENCE/Planar/Planar.html
Hot Plate results - Greg Egan
"This page shows some results computed with the Hot Plate applet.
* Displacement vs particle number
* Force on locked plate vs particle number
Displacement vs particle number
For particle radius 10-2 and 10-3, the displacement at t=100 reaches a peak at around 250 particles. For particle radius 10-4, the results are too noisy to be useful."
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMillResults2.html
* Displacement vs particle number
* Force on locked plate vs particle number
Displacement vs particle number
For particle radius 10-2 and 10-3, the displacement at t=100 reaches a peak at around 250 particles. For particle radius 10-4, the results are too noisy to be useful."
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMillResults2.html
Light Mill results - Greg Egan
"This page shows some results computed with the Light Mill applet (follow that link for the applet itself, along with details of the toy model that the applet simulates).
* Locked rotor
* Varying the rotor's outer radius"
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMillResults.html
* Locked rotor
* Varying the rotor's outer radius"
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMillResults.html
Hot Plate Applet - Greg Egan
"The applet below is a simplification of the Light Mill applet, in which a single plate (hotter on the black side than the white side) is constrained to move only horizontally in a container with wrap-around topology: when anything reaches the left or right edge it moves instantly to the opposite edge. (The top and bottom edges are ordinary walls.) All the physics for this applet is essentially the same as for the Light Mill applet; this version basically just changes the geometry to make the situation less complex. Note that the width and height of the container are 1.0, the same as the radius for the Light Mill applet, so the area of this container is smaller."
3.5 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMill2.html
3.5 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMill2.html
Orthogonal - Greg Egan
A little about the upcoming novel can be found at the link :
"In Yalda's universe, light has no universal speed and its creation generates energy.
On Yalda's world, plants make food by emitting their own light into the dark night sky."
4 out of 5
http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html
"In Yalda's universe, light has no universal speed and its creation generates energy.
On Yalda's world, plants make food by emitting their own light into the dark night sky."
4 out of 5
http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html
Distress 1 - Greg Egan
"ll right. He's dead. Go ahead and talk to him.”
The bioethicist was a laconic young asex with blond dreadlocks and a T-shirt which flashed up the slogan SAY NO TO TOE! in between the paid advertising. Ve countersigned the permission form on the forensic pathologist's notepad, then withdrew to a corner of the room. The trauma specialist and the paramedic wheeled their resuscitation equipment out of the way, and the forensic pathologist hurried forward, hypodermic syringe in hand, to administer the first dose of neuropreservative. Useless prior to legal death — massively toxic to several organs, on a time scale of hours — the cocktail of glutamate antagonists, calcium channel blockers, and antioxidants would halt the most damaging biochemical changes in the victim's brain, almost immediately.
The pathologist's assistant followed close behind her, with a trolley bearing all the paraphernalia of post-mortem revival: a tray of disposable surgical instruments; several racks of electronic equipment; an arterial pump fed from three glass tanks the size of water-coolers; and something resembling a hairnet made out of grey superconducting wire.
Lukowski, the homicide detective, was standing beside me. He mused, “If everyone was fitted out like you, Worth, we'd never have to do this. We could just replay the crime from start to finish. Like reading an aircraft's black box.”"
4.5 out of 5
http://www.gregegan.net/DISTRESS/Excerpt/DistressExcerpt.html
The bioethicist was a laconic young asex with blond dreadlocks and a T-shirt which flashed up the slogan SAY NO TO TOE! in between the paid advertising. Ve countersigned the permission form on the forensic pathologist's notepad, then withdrew to a corner of the room. The trauma specialist and the paramedic wheeled their resuscitation equipment out of the way, and the forensic pathologist hurried forward, hypodermic syringe in hand, to administer the first dose of neuropreservative. Useless prior to legal death — massively toxic to several organs, on a time scale of hours — the cocktail of glutamate antagonists, calcium channel blockers, and antioxidants would halt the most damaging biochemical changes in the victim's brain, almost immediately.
The pathologist's assistant followed close behind her, with a trolley bearing all the paraphernalia of post-mortem revival: a tray of disposable surgical instruments; several racks of electronic equipment; an arterial pump fed from three glass tanks the size of water-coolers; and something resembling a hairnet made out of grey superconducting wire.
Lukowski, the homicide detective, was standing beside me. He mused, “If everyone was fitted out like you, Worth, we'd never have to do this. We could just replay the crime from start to finish. Like reading an aircraft's black box.”"
4.5 out of 5
http://www.gregegan.net/DISTRESS/Excerpt/DistressExcerpt.html
Monday, June 7, 2010
Light Mill Applet - Greg Egan
"The applet below is a very simple toy model that might be useful for exploring some aspects of the “Light Mill” or “Crookes Radiometer”, which was once thought to rotate due to radiation pressure. It's now known that thermal effects associated with residual gas drive the rotation, but the details remain somewhat contentious, as discussed in this thread on the n-Category Café. Some results obtained with this applet are collected on on this companion page.
This applet performs a very simple, two-dimensional particle-based simulation; it certainly does not come remotely close to capturing the actual physics of the real device. The units of distance are such that the outer radius of the container is 1; the units of time and mass are arbitrary."
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMill.html
This applet performs a very simple, two-dimensional particle-based simulation; it certainly does not come remotely close to capturing the actual physics of the real device. The units of distance are such that the outer radius of the container is 1; the units of time and mass are arbitrary."
4 out of 5
http://www.gregegan.net/SCIENCE/LightMill/LightMill.html
The Planck Dive - Greg Egan
"The key idea dated back to Sakharov: gravity was nothing but the residue of the imperfect cancellation of other forces; squeeze the quantum vacuum hard enough and Einstein's equations fell out. But since Einstein, every theory of gravity was also a theory of time. Relativity demanded that a free-falling particle's rotating phase agree with every other clock that traveled the same path, and once gravitational time dilation was linked to changes in virtual particle density, every measure of time--from the half-life of a radioisotope's decay (stimulated by vacuum fluctuations) to the vibrational modes of a sliver of quartz (ultimately due to the same phase effects as those giving rise to classical paths)--could be reinterpreted as a count of interactions with virtual particles.
It was this line of reasoning that had led Kumar--a century after Sakharov, building on work by Penrose, Smolin and Rovelli--to devise a model of spacetime as a quantum sum of every possible network of particle world lines, with classical "time" arising from the number of intersections along a given strand of the net. This model had been an unqualified success, surviving theoretical scrutiny and experimental tests for centuries. But it had never been validated at the smallest length scales, accessible only at absurdly high energies, and it made no attempt to explain the basic structure of the nets, or the rules that governed them. Gisela wanted to know where those details came from. She wanted to understand the universe at its deepest level, to touch the beauty and simplicity that lay beneath it all.
That was why she was taking the Planck Dive."
4 out of 5
http://www.fictionwise.com/ebooks/b919/The-Planck-Dive/Greg-Egan/?si=0
It was this line of reasoning that had led Kumar--a century after Sakharov, building on work by Penrose, Smolin and Rovelli--to devise a model of spacetime as a quantum sum of every possible network of particle world lines, with classical "time" arising from the number of intersections along a given strand of the net. This model had been an unqualified success, surviving theoretical scrutiny and experimental tests for centuries. But it had never been validated at the smallest length scales, accessible only at absurdly high energies, and it made no attempt to explain the basic structure of the nets, or the rules that governed them. Gisela wanted to know where those details came from. She wanted to understand the universe at its deepest level, to touch the beauty and simplicity that lay beneath it all.
That was why she was taking the Planck Dive."
4 out of 5
http://www.fictionwise.com/ebooks/b919/The-Planck-Dive/Greg-Egan/?si=0
Our Lady Of Chernobyl - Greg Egan
"I said carefully, "Nothing is ever really lost. You might find that a strongly-worded letter from your lawyers to the courier is enough to work miracles."
Masini smiled humourlessly. "I don't think so. The courier is dead."
Afternoon light filled the room; the window faced east, away from the sun, but the sky itself was dazzling. I suffered a moment of strange clarity, a compelling sense of having just shaken off a lingering drowsiness, as if I'd begun the conversation half asleep and only now fully woken. Masini let the copper orrery on the wall behind me beat twice, each tick a soft, complicated meshing of a thousand tiny gears. Then he said, "She was found in a hotel room in Vienna, three days ago. She'd been shot in the head at close range. And no, she was not meant to take any such detour."
3.5 out of 5
http://www.fictionwise.com/ebooks/b935/Our-Lady-Of-Chernobyl/Greg-Egan/?si=0
Masini smiled humourlessly. "I don't think so. The courier is dead."
Afternoon light filled the room; the window faced east, away from the sun, but the sky itself was dazzling. I suffered a moment of strange clarity, a compelling sense of having just shaken off a lingering drowsiness, as if I'd begun the conversation half asleep and only now fully woken. Masini let the copper orrery on the wall behind me beat twice, each tick a soft, complicated meshing of a thousand tiny gears. Then he said, "She was found in a hotel room in Vienna, three days ago. She'd been shot in the head at close range. And no, she was not meant to take any such detour."
3.5 out of 5
http://www.fictionwise.com/ebooks/b935/Our-Lady-Of-Chernobyl/Greg-Egan/?si=0
Oceanic - Greg Egan
"He said, "Archaeologists have shown that we must have arrived about twenty thousand years ago. Before that, there's no evidence of humans, or any co-ecological plants and animals. That makes the Crossing older than the Scriptures say, but there are some dates that are open to interpretation, and with a bit of poetic license everything can be made to add up. And most biologists think the native microfauna could have formed by itself over millions of years, starting from simple chemicals, but that doesn't mean God didn't guide the whole process. Everything's compatible, really. Science and the Scriptures can both be true."
I thought I knew where he was headed, now. "So you've worked out a way to use science to prove that God exists?" I felt a surge of pride; my brother was a genius!
"No." Daniel was silent for a moment. "The thing is, it works both ways. Whatever's written in the Scriptures, people can always come up with different explanations for the facts. The ships might have left Earth for some other reason. The Angels might have made bodies for themselves for some other reason. There's no way to convince a non-believer that the Scriptures are the word of God. It's all a matter of faith.""
4 out of 5
http://www.fictionwise.com/ebooks/b922/Oceanic/Greg-Egan/?si=0
I thought I knew where he was headed, now. "So you've worked out a way to use science to prove that God exists?" I felt a surge of pride; my brother was a genius!
"No." Daniel was silent for a moment. "The thing is, it works both ways. Whatever's written in the Scriptures, people can always come up with different explanations for the facts. The ships might have left Earth for some other reason. The Angels might have made bodies for themselves for some other reason. There's no way to convince a non-believer that the Scriptures are the word of God. It's all a matter of faith.""
4 out of 5
http://www.fictionwise.com/ebooks/b922/Oceanic/Greg-Egan/?si=0
Cocoon - Greg Egan
"Lansing said, "Our main project here was engineering improved syncytiotrophoblastic cells." I smiled patiently, and she translated for me. "Strengthening the barrier between the maternal and fetal blood supplies. Mother and fetus don't share blood directly, but they exchange nutrients and hormones across the placental barrier. The trouble is, all kinds of viruses, toxins, pharmaceuticals and illicit drugs can also cross over. The natural barrier cells didn't evolve to cope with HIV, fetal alcohol syndrome, cocaine-addicted babies, or the next thalidomide-like disaster. We're aiming for a single intravenous injection of a gene-tailoring vector, which would trigger the formation of an extra layer of cells in the appropriate structures within the placenta, specifically designed to shield the fetal blood supply from contaminants in the maternal blood."
"A thicker barrier?"
"Smarter. More selective. More choosy about what it lets through. We know exactly what the developing fetus actually needs from the maternal blood. These gene-tailored cells would contain specific channels for transporting each of those substances. Nothing else would be allowed through.""
4.5 out of 5
http://www.fictionwise.com/ebooks/b955/Cocoon/Greg-Egan/?si=0
"A thicker barrier?"
"Smarter. More selective. More choosy about what it lets through. We know exactly what the developing fetus actually needs from the maternal blood. These gene-tailored cells would contain specific channels for transporting each of those substances. Nothing else would be allowed through.""
4.5 out of 5
http://www.fictionwise.com/ebooks/b955/Cocoon/Greg-Egan/?si=0
Chaff - Greg Egan
"Colombia was tearing itself apart; La Violencia of the 1950s, all over again. Although all of the spectacular terrorist sabotage was being carried out by organized guerilla groups, most of the deaths so far had been caused by factions within the two mainstream political parties butchering each other's supporters, avenging a litany of past atrocities which stretched back for generations. The group who'd actually started the current wave of bloodshed had negligible support; Ejército de Simon BolÃvar were lunatic right-wing extremists who wanted to "reunite" with Panama, Venezuela, and Ecuador--after two centuries of separation--and drag in Peru and Bolivia, to realize BolÃvar's dream of Gran Colombia. By assassinating President MarÃn, though, they'd triggered a cascade of events that had nothing to do with their ludicrous cause. Strikes and protests, street battles, curfews, martial law. The repatriation of foreign capital by nervous investors, followed by hyperinflation, and the collapse of the local financial system. Then a spiral of opportunistic violence. Everyone, from the paramilitary death squads to the Maoist splinter groups, seemed to believe that their hour had finally come."
3.5 out of 5
http://www.fictionwise.com/ebooks/b933/Chaff/Greg-Egan/?si=0
3.5 out of 5
http://www.fictionwise.com/ebooks/b933/Chaff/Greg-Egan/?si=0
Transition Dreams - Greg Egan
""I understand. But if my brain has been shut down by hypothermia ... why will I dream?"
"Your brain won't do the dreaming. The software model we're creating will. But as I said, you won't remember any of it. In the end, the software will be a perfect Copy of your--deeply comatose--organic brain, and it will wake from that coma remembering exactly what the organic brain experienced before the scan. No more, no less. And since the organic brain certainly won't have experienced the transition dreams, the software will have no memory of them.""
4 out of 5
http://www.fictionwise.com/ebooks/b876/Transition-Dreams/Greg-Egan/?si=0
"Your brain won't do the dreaming. The software model we're creating will. But as I said, you won't remember any of it. In the end, the software will be a perfect Copy of your--deeply comatose--organic brain, and it will wake from that coma remembering exactly what the organic brain experienced before the scan. No more, no less. And since the organic brain certainly won't have experienced the transition dreams, the software will have no memory of them.""
4 out of 5
http://www.fictionwise.com/ebooks/b876/Transition-Dreams/Greg-Egan/?si=0
Silver Fire - Greg Egan
"When the Silver Fire virus infected fibroblasts in the subcutaneous connective tissue, it caused them to go into overdrive, manufacturing vast quantities of collagen--in a variant form transcribed from the normal gene but imperfectly assembled. This denatured protein formed solid plaques in the extracellular space, disrupting the nutrient flow to the dermis above--and eventually becoming so bulky as to shear it off completely. Silver Fire flayed you from within. A good strategy for releasing large amounts of virus, maybe--though when it had stumbled on the trick, no one knew. The presumed animal host in which the parent strain lived, benignly or otherwise, was yet to be found."
4 out of 5
http://www.fictionwise.com/ebooks/b973/Silver-Fire/Greg-Egan/?si=0
4 out of 5
http://www.fictionwise.com/ebooks/b973/Silver-Fire/Greg-Egan/?si=0
Reasons to Be Cheerful - Greg Egan
"The pressure in my skull explained most of my symptoms, but tests on my cerebrospinal fluid had also revealed a greatly elevated level of a substance called Leu-enkephalin--an endorphin, a neuropeptide which bound to some of the same receptors as opiates like morphine and heroin. Somewhere along the road to malignancy, the same mutant transcription factor that had switched on the genes enabling the tumor cells to divide unchecked had apparently also switched on the genes needed to produce Leu-enkephalin."
4 out of 5
http://www.fictionwise.com/ebooks/b975/Reasons-To-Be-Cheerful/Greg-Egan/?si=0
4 out of 5
http://www.fictionwise.com/ebooks/b975/Reasons-To-Be-Cheerful/Greg-Egan/?si=0
Mitochondrial Eve - Greg Egan
"In the foyer, a holographic bust of Mitochondrial Eve herself, mounted on a marble pedestal, gazed proudly over our heads. The artist had rendered our hypothetical ten-thousand-times-great grandmother as a strikingly beautiful woman. A subjective judgment, certainly--but her lean, symmetrical features, her radiant health, her purposeful stare, didn't really strike me as amenable to subtleties of interpretation. The esthetic buttons being pushed were labeled, unmistakably: warrior, queen, goddess. And I had to admit that I felt a certain bizarre, involuntary swelling of pride at the sight of her ... as if her regal bearing and fierce eyes somehow "ennobled" me and all her descendants ... as if the "character" of the entire species, our potential for virtue, somehow depended on having at least one ancestor who could have starred in a Leni Riefenstahl documentary."
3.5 out of 5
http://www.fictionwise.com/ebooks/b918/Mitochondrial-Eve/Greg-Egan/?si=0
3.5 out of 5
http://www.fictionwise.com/ebooks/b918/Mitochondrial-Eve/Greg-Egan/?si=0
Mister Volition - Greg Egan
"He calls up another database, and types PAN*. "Ah. No catalog entry. So--it's black market ... unapproved!" He grins at me, like a schoolkid daring another to eat a worm. "But what's the worst it can do?"
"I don't know. Brainwash me?""
3.5 out of 5
http://www.fictionwise.com/ebooks/b900/Mister-Volition/Greg-Egan/?si=0
"I don't know. Brainwash me?""
3.5 out of 5
http://www.fictionwise.com/ebooks/b900/Mister-Volition/Greg-Egan/?si=0
Luminous - Greg Egan
"I spoke softly, in English. "What you're in the process of hacking out of me is a necrotrap. One heartbeat without oxygenated blood, and the cargo gets fried."
My amateur surgeon was compact, muscular, with short black hair. Not Chinese; Indonesian, maybe. If she was surprised that I'd woken prematurely, she didn't show it. The gene-tailored hepatocytes I'd acquired in Hanoi could degrade almost anything from morphine to curare; it was a good thing the local anesthetic was beyond their reach.
Without taking her eyes off her work, she said, "Look on the table next to the bed."
I twisted my head around. She'd set up a loop of plastic tubing full of blood--mine, presumably--circulated and aerated by a small pump. The stem of a large funnel fed into the loop, the intersection controlled by a valve of some kind. Wires trailed from the pump to a sensor taped to the inside of my elbow, synchronizing the artificial pulse with the real. I had no doubt that she could tear the trap from my vein and insert it into this substitute without missing a beat."
5 out of 5
http://www.fictionwise.com/ebooks/b974/Luminous/Greg-Egan/?si=0
My amateur surgeon was compact, muscular, with short black hair. Not Chinese; Indonesian, maybe. If she was surprised that I'd woken prematurely, she didn't show it. The gene-tailored hepatocytes I'd acquired in Hanoi could degrade almost anything from morphine to curare; it was a good thing the local anesthetic was beyond their reach.
Without taking her eyes off her work, she said, "Look on the table next to the bed."
I twisted my head around. She'd set up a loop of plastic tubing full of blood--mine, presumably--circulated and aerated by a small pump. The stem of a large funnel fed into the loop, the intersection controlled by a valve of some kind. Wires trailed from the pump to a sensor taped to the inside of my elbow, synchronizing the artificial pulse with the real. I had no doubt that she could tear the trap from my vein and insert it into this substitute without missing a beat."
5 out of 5
http://www.fictionwise.com/ebooks/b974/Luminous/Greg-Egan/?si=0
Sunday, June 6, 2010
Klein's Quartic Equation - Greg Egan
"Klein's quartic curve is a surface of genus 3 (a three-holed torus) of constant negative curvature. It can be constructed by specifying a 14-gon in the hyperbolic plane and identifying pairs of edges. However, it can also be constructed as the solution to Klein's wonderfully simple equation:
u3v + v3w + w3u = 0
You can read Klein's derivation of this equation in his original article on the quartic curve, “On the Order-Seven Transformation of Elliptic Functions”, translated into English in this book:
The Eightfold Way: the Beauty of Klein's Quartic Curve, edited by Silvio Levy; MSRI Research Publications 35, Cambridge University Press, Cambridge 1999."
5 out of 5
http://www.gregegan.net/SCIENCE/KleinQuartic/KleinQuarticEq.html
u3v + v3w + w3u = 0
You can read Klein's derivation of this equation in his original article on the quartic curve, “On the Order-Seven Transformation of Elliptic Functions”, translated into English in this book:
The Eightfold Way: the Beauty of Klein's Quartic Curve, edited by Silvio Levy; MSRI Research Publications 35, Cambridge University Press, Cambridge 1999."
5 out of 5
http://www.gregegan.net/SCIENCE/KleinQuartic/KleinQuarticEq.html
Saturday, June 5, 2010
Klein's Quartic Curve - Greg Egan
"Klein's quartic curve is a surface of genus 3, which is to say that it is like a 3-holed torus. As well as having that topology, the surface has a metric (a definition of distances and angles) of constant negative curvature, which means it has the local geometry of the hyperbolic plane. By drawing a 14-sided polygon in the hyperbolic plane and indicating that certain edges need to be connected to each other, you can specify the geometry of Klein's quartic curve completely. There are a variety of other ways to specify the curve, most of them involving algebra and/or complex analysis. I've written a simple account of the construction of the curve via the wonderful quartic equation for it, u3v+v3w+w3u=0, in this page on Klein's quartic equation."
5 out of 5
http://www.gregegan.net/SCIENCE/KleinQuartic/KleinQuartic.html
5 out of 5
http://www.gregegan.net/SCIENCE/KleinQuartic/KleinQuartic.html
General Relativity in 2+1 dimensions - Greg Egan
"In 2+1 dimensions, Einstein's equation in a vacuum requires that spacetime is completely flat. This is in stark contrast to the situation in 3+1 dimensions, where the vacuum solutions are only required to be “Ricci flat”, that is, the Ricci curvature tensor must be zero, but the complete, Riemann curvature tensor need not be, allowing for gravitational waves, and for the familiar gravitational effects of the sun on the Earth, and so on."
5 out of 5
http://www.gregegan.net/SCIENCE/GR2plus1/GR2plus1.html
5 out of 5
http://www.gregegan.net/SCIENCE/GR2plus1/GR2plus1.html
Orphanogenesis - Joe Schacher
"Inspired by Greg Egan's novel Diaspora, Orphanogenesis describes the birth of a very special child. This child comes into being not as a combination of two people's genetic material, but as a spontaneous construct with only the most basic common threads coming from many sources."
3.5 out of 5
http://composersforum.ning.com/forum/attachment/download?id=773368%3AUploadedFi105%3A136359
3.5 out of 5
http://composersforum.ning.com/forum/attachment/download?id=773368%3AUploadedFi105%3A136359
Friday, June 4, 2010
A Simple Asymmetric Resonant Cavity - Greg Egan
"This web page analyses an extremely simple example of an asymmetric resonant cavity: a tapered quadrilateral in two dimensions. The analysis demonstrates that the net force on the cavity walls is zero, providing a simple counterexample to the absurd claim by the British engineer Roger Shawyer [2] that closing off the ends of a tapered waveguide will produce a cavity that can experience a net force from internal radiation pressure (a claim, sadly, much hyped by the magazine New Scientist [1])."
5 out of 5
http://www.gregegan.net/SCIENCE/Cavity/Simple.html
5 out of 5
http://www.gregegan.net/SCIENCE/Cavity/Simple.html
Thursday, June 3, 2010
Resonant Modes of a Conical Cavity - Greg Egan
"In September 2006, the magazine New Scientist published an unfortunate beat-up [1] in which they hyped the immensely unlikely claims of a British engineer named Roger Shawyer, who had designed what he described as an “electromagnetic drive” (aka “EmDrive”) for satellites. This device supposedly produced a net thrust solely by bouncing microwaves back and forth in a closed metal cavity, the idea being that making the cavity asymmetric would mean that a greater force would be exerted by the microwaves on one end compared to the other, causing the entire device to accelerate [2]."
5 out of 5
http://www.gregegan.net/SCIENCE/Cavity/Cavity.html
5 out of 5
http://www.gregegan.net/SCIENCE/Cavity/Cavity.html
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