May 17, 2004
Parsing 'A Verbless Post'
This is getting a bit ridiculous, but here goes:
A follow up to a previous post about Part-of-speech Tagging 'A Verbless Post' in which Geoff Pullum's post to the language log was analyzed for parts of speech. This post uses Eugene Charniak's statistical parser (parser03) to produce a syntactic analysis of the contents (in the Penn Treebank notation).
First thing to notice in the parser output is that the recall for humourous points scored is substantially reduced due to the fact that no verb to Thaler is produced:
(S1 (S (CC And) (PP (IN in) (NP (DT that) (NN case))) (, ,) (NP (NP (DT a) (NN word)) (PP (IN of) (NP (NP (NN gratitude)) (PP (TO to) (NP (NNP Thaler)))))) (VP (PRN (-LRB- -LCB-) (ADVP (RB otherwise)) (NP (DT an) (JJ unimportant) (NN screwball)) (-RRB- -RCB-))) (. .)))
However, overall the poor parser is strained by the lack of verbs more than the tagger seemed to be, mainly due to the added pressure of producing legitimate syntactic structures. Because verb phrases occur frequently in the training data, the parser produces structures with spurious VPs in some unfamiliar contexts:
(S1 (S (NP (IN Except)) (VP (VBZ ..)) (. .)))
(VP (VBZ nouns) (NP (, ,) (NNS pronouns) ... )
Our experience in trying to parse the output of a statistical machine translation system on the NIST 02/03 data for Chinese to English translation led to similar issues of hallucinated verb phrases for some of the ungrammatical English sentences output by the system. This behaviour is documented in this paper (from HLT-NAACL, 2004).
Understanding the notation of these parse trees is likely to be more challenging for the layperson (I would hope). For the intrepid reader, a good start would be the Penn Treebank manuals.
If you examine the full output of the Charniak parser on Geoff Pullum's post (shown below), there are some strange errors in punctuations, and the usual prepositional phrase (PP) and coordination (CC) attachment errors. But, overall, the performance is very good, especially for some useful constituents like noun phrases (NPs) or parentheticals (PRN).
(S1 (NP (DT A) (JJ verbless) (NN novel) (. ?))) (S1 (FRAG (WRB Why) (. ?) (. ?))) (S1 (NP (NP (WP What) (NN reason)) (PP (IN for) (NP (NP (DT the) (NN accomplishment)) (PP (IN by) (NP (NP (DT this) (JJ showy) (NN fool)) (PP (IN in) (NP (NP (NNP France)) (, ,) (NP (NNP Michel)))))))))) (S1 (FRAG (NP (NNP Thaler)) (, ,) (NP (NP (PRP$ his) (NN effort)) (PP (IN at) (NP (NP (DT an) (JJ entire) (NN novel)) (PP (IN with) (NP (DT no) (NNS verbs))))) (PRN (-LRB- -LCB-) (NP (RB perhaps) (RB not) (NP (DT a) (ADJP (JJ wise) (CC or) (JJ lucrative)) (NN publication) (NN venture)) (, ,) (VP (VBN given) (NP (NP (DT the) (RB not) (JJ total) (NN incorrectness)) (PP (IN of) (NP (PRP$ my) (NNS speculations)))))) (-RRB- -RCB-)) (ADJP (RB recently) (JJ evident))) (PP (IN amongst) (NP (NP (DT the) (JJ vast) (FW efflux)) (PP (IN of) (NP (NP (JJ absurd) (JJ literary) (NN pretense)) (PP (IN in) (NP (DT the) (JJ French) (NN language))))))) (. ?))) (S1 (FRAG (INTJ (UH Well)) (, ,) (SBAR (WHNP (WDT whatever)) (S (NP (PRP$ his) (NNS reasons)) (, ,) (PP (IN in) (NP (NN response))) (, ,) (NP (PRP$ my) (JJ own) (NN contribution)) (: :) (NP (NP (DT a) (JJ verbless) (NN post)) (-LRB- -LCB-) (NP (NP (DT the) (JJ first)) (PP (IN on) (NP (NN Language) (NN Log)))) (-RRB- -RCB-)))) (. .))) (S1 (S (NP (NP (DT No) (NNS verbs)) (PP (IN at) (NP (NP (DT all)) (PP (IN in) (NP (NP (DT this) (NN book)) (PP (IN of) (NP (NP (NNP Thaler) (POS 's)) (, ,) (ADVP (RB just))))))))) (VP (VBZ nouns) (NP (, ,) (NNS pronouns) (, ,) (NNS adjectives) (, ,) (NNS adverbs) (, ,) (NNS prepositions) (, ,) (NNS subordinators) (, ,) (NNS coordinators) (, ,) (CC and) (PRN (: --) (INTJ (UH oh) (. !)) (: --)) (NNS interjections))) (. .))) (S1 (S (NP (PDT All) (DT those)) (PP (IN among) (NP (DT the) (JJ permissible) (PRN (-LRB- -LCB-) (CC and) (PP (IN for) (NP (PRP him))) (, ,)) (NN past))) (VP (VBZ participles) (ADVP (RB too)) (, ,) (PP (IN though) (NP (NP (DT no) (JJ participial) (NNS intrusions)) (PP (IN in) (NP (DT this) (NN post))))) (, ,) (NP (NP (NP (PDT such) (DT the) (JJ extreme) (NN character)) (PP (IN of) (NP (PRP$ my) (ADJP (JJ cruel) (CC and) (JJ unreasonable)) (JJ self-applicable) (NNS strictures) (-RRB- -RCB-)))) (, ,) (CC but) (RB never) (NP (CD one) (JJ single) (JJ solitary) (NN verb)))) (. .))) (S1 (S (CC And) (, ,) (ADVP (RB fantastically)) (, ,) (NP (PDT all) (DT this)) (VP (NP (NP (NP (DT a) (NN vision)) (PP (IN of) (NP (NP (DT some) (NN liberation)) (PP (IN for) (NP (NNS authors)))))) (, ,) (RB not) (NP (NP (DT an) (JJ absurd) (JJ literary) (NN straitjacket)) (PP (IN with) (NP (DT the) (NN writer))))) (PRN (-LRB- -LCB-) (PP (IN albeit) (NP (RB willingly))) (-RRB- -RCB-)) (VP (VBN imprisoned) (PP (IN within) (NP (PRP it))))) (. .))) (S1 (NP (NP (DT Some) (NN freedom)) (, ,) (NP (DT this)) (. .))) (S1 (FRAG (NP (NNP Thaler)) (: :) (S (NP (NNS nuts) (, ,) (NNS bonkers) (, ,)) (VP (VBP round) (DT the) (VP (VB bend)))) (. .))) (S1 (NP (NP (JJ Mad)) (PP (IN as) (NP (DT a) (NNP March) (NN hare))) (. .))) (S1 (S (NP (DT The) (NNP Liberman) (NN conjecture)) (PRN (-LRB- -LCB-) (PP (IN about) (NP (NP (NN survival)) (PP (IN of) (NP (NP (JJ high) (NN school) (JJ literary) (NN experimentation)) (PP (IN into) (NP (NP (NN adulthood)) (PP (IN because) (IN of) (NP (DT a) (ADJP (JJ dysfunctional) (JJ authoritarian)) (JJ French) (JJ educational) (NN system))))))))) (-RRB- -RCB-)) (: :) (S (ADVP (RB probably)) (ADJP (JJ true))) (. .))) (S1 (NP (NP (PRP$ My) (NN attitude)) (: :) (NP (NP (NN contempt)) (, ,) (ADVP (RB really))) (. .))) (S1 (S (NP (IN Except)) (VP (VBZ ..)) (. .))) (S1 (FRAG (PP (IN Unless) (NP (CD ..))) (. .))) (S1 (S (ADVP (RB Just) (RB possibly)) (, ,) (NP (NP (DT an) (NN exercise)) (, ,) (PP (IN for) (NP (NP (DT the) (NNS undergraduates)) (PP (IN in) (NP (NP (PRP$ my) (NN course)) (PP (IN on) (NP (NNP English)))))))) (VP (NN grammar) (NP (DT this) (NN fall) (NN quarter))) (. .))) (S1 (NP (NP (DT An) (NN effort)) (PP (IN at) (NP (NP (NN construction)) (PP (IN of) (NP (NP (JJ fifty) (NNS words)) (PP (IN of) (NP (NP (JJ coherent) (NN prose)) (PP (IN with) (NP (NP (ADVP (RB never)) (DT a) (NN verb)) (, ,) (PP (IN with) (NP (NP (RB only) (DT those)) (PP (IN in) (NP (NP (NN possession)) (PP (IN of) (NP (NP (JJ enough) (JJ grammatical) (NN knowledge)) (PP (IN for) (NP (NP (JJ verb) (NN identification)) (ADJP (JJ capable) (PP (IN of) (NP (NN success)))))))))))))))))))) (. .))) (S1 (FRAG (ADJP (JJ Worth) (S (NP (DT a) (NN try)))) (, ,) (ADVP (RB perhaps)) (. .))) (S1 (S (CC And) (PP (IN in) (NP (DT that) (NN case))) (, ,) (NP (NP (DT a) (NN word)) (PP (IN of) (NP (NP (NN gratitude)) (PP (TO to) (NP (NNP Thaler)))))) (VP (PRN (-LRB- -LCB-) (ADVP (RB otherwise)) (NP (DT an) (JJ unimportant) (NN screwball)) (-RRB- -RCB-))) (. .))) (S1 (FRAG (NP (RB Always) (DT that) (JJ extra) (NN possibility)) (: :) (S (NP (DT the) (NN idea)) (VP (VBP justifiable) (PP (RB not) (PP (IN because) (IN of) (NP (PRP$ its) (NN implementation))) (, ,) (CC but) (PP (IN in) (NP (NP (NN virtue)) (PP (IN of) (NP (NP (DT a) (ADJP (JJ complementary) (CC or) (JJ counterposed)) (NN idea) (NN emergent)) (PP (IN in) (NP (NP (DT the) (NN mind)) (PP (IN of) (NP (NP (NN someone) (RB else)) (: --) (NP (NP (JJ serendipitous) (JJ bastard) (NN offspring)) (PP (IN of) (NP (DT a) (JJ deranged) (JJ cognitive) (NN parent))))))))))))))) (. .))) (S1 (FRAG (RB So) (NP (NP (PRP$ my) (NN gratitude)) (PP (TO to) (NP (PRP you)))) (, ,) (NP (NNP Thaler)) (, ,) (NP (PRP you) (JJ pusillanimous) (NN poseur)) (, ,) (NP (PRP you) (JJ literary) (NN clown)) (. .))) (S1 (NP (DT A) (JJ new) (NN idea) (. !))) (S1 (FRAG (NP (PRP$ My) (NN idea)) (, ,) (NP (NP (DT all) (NN mine)) (PRN (-LRB- -LCB-) (NP (NP (ADJP (JJ accessible) (PP (ADVP (RB here)) (IN on) (NP (NN Language)))) (NN Log)) (PP (TO to) (NP (QP (RB just) (DT a) (JJ few) (CD thousand)) (JJ close) (NNS friends)))) (-RRB- -RCB-))) (. .))) (S1 (FRAG (NP (NNP Ooh)) (, ,) (NP (CD one) (JJ other) (NN thought)) (, ,) (PP (IN for) (NP (JJ computational) (NNS linguists))) (: :) (SBAR (WHNP (WP What)) (S (VP (NNS bets) (PP (IN on) (NP (NP (DT the) (NN performance)) (PP (IN of) (NP (NP (JJ part-of-speech) (VBG tagging) (NNS algorithms)) (PP (IN on) (NP (NN prose))) (PP (JJ such) (IN as) (NP (DT this)))))))))) (. ?)))
QED: The Strange Theory of Light and Matter by Richard P. Feynman
The QED in the title stands for Quantum Electrodynamics and this is a book explaining this physical theory which underlies phenomena as diverse as heat, magnetism, electricity, light, X-rays, ultraviolet rays, indices of refraction and coefficients of refraction among other properties.
This book has the clearest descriptions and explanations of the so-called wave-particle duality that I have read. It is not as easy to read as Feynman's other book of lectures "The Character of Physical Law", however the payoff is greater as well. By the end of this book you might just get a real feeling of exactly how counter-intuitive Nature can be.
This book is a transcription of four lectures given by Feynman at UCLA to a non-expert audience. However, Feynman does not pull any punches and does not dilute the subject matter to the point that it becomes vacuous. By the end of the book, you are actually comfortable with his non-notational method of computing the probability of photon transmissions.
Feynman's style is as usual conversational and informal, although the figures and the text do not flow together very well since each figure has a detailed description of its own and it feels like it was added later as an afterthought even though the text refer to the figures often. This is perhaps a side-effect of this book being transcriptions of the original lectures.
%T QED: The Strange Theory of Light and Matter %A Richard P. Feynman %I Princeton Science Library %D 1985 %G ISBN: 0691083886 (hc) %G ISBN: 0691024170 (pb) %P 158 %K science, physics
Review written: 1999/07/26
May 15, 2004
Axiomatic by Greg Egan
A collection of short stories. Very enjoyable, but not as consistently good overall as "Luminous", another collection of short stories by Greg Egan.
My favorites in this collection were:
- "The Hundred Light-Year Diary", which uses the interesting premise that time will run in reverse when the universe contracts. This premise was proven to be false by Hawking, I believe, since the story was published;
- "The Caress", which combines bio-engineering with art history (the story takes its name from an 1896 painting by the Belgian symbolist artist Fernand Khnopff);
- "Seeing", an interesting neuroscientific speculation about visual processing in the brain.
- Also, "A Kidnapping" fore shadows some of the plot elements that he used later in "Permutation City".
%T Axiomatic %A Greg Egan %I HarperPrism %D 1997 %G ISBN: 0061052655 %P 293 %K science-fiction
Review written: circa 1999
May 12, 2004
Part-of-Speech Tagging 'A Verbless Post'
Geoffrey Pullum, in full TOPIC .. COMMENT form, has posted on the language log, a reasoned critique entitled A Verbless Post of Michael Thaler's verbophobic novel. Pullum's post, of course, contains no verbs, but more to the point for this posting, has the following concluding statement:
Ooh, one other thought, for computational linguists: What bets on the performance of part-of-speech tagging algorithms on prose such as this?
I reached for Adwait Ratnaparkhi's aging but conveniently handy Maximum Entropy part-of-speech tagger and ran it on Pullum's post.
The first thing to notice about the output is the depressing amount of tokenization it takes to make sure that spurious errors do not arise.
Errors? Of course, there are some, but not as many as one would expect. More importantly, the tagger puts its own label biased tongue in its cheek and creates a new verb, to Thaler:
And_CC in_IN that_DT case_NN ,_, a_DT word_NN of_IN gratitude_NN to_TO Thaler_VB -LCB-_-LRB- otherwise_RB an_DT unimportant_JJ screwball_NN -RCB-_-RRB- ._.
Here is the entire output of the tagger on Pullum's post:
A_DT verbless_JJ novel_NN ?_. Why_WRB ?_. ?_. What_WP reason_NN for_IN the_DT accomplishment_NN by_IN this_DT showy_NN fool_NN in_IN France_NNP ,_, Michel_NNP Thaler_NNP ,_, his_PRP$ effort_NN at_IN an_DT entire_JJ novel_NN with_IN no_DT verbs_NNS -LCB-_-LRB- perhaps_RB not_RB a_DT wise_JJ or_CC lucrative_JJ publication_NN venture_NN ,_, given_VBN the_DT not_RB total_JJ incorrectness_NN of_IN my_PRP$ speculations_NNS -RCB-_-RRB- recently_RB evident_JJ amongst_IN the_DT vast_JJ efflux_NN of_IN absurd_JJ literary_JJ pretense_NN in_IN the_DT French_JJ language_NN ?_. Well_UH ,_, whatever_WDT his_PRP$ reasons_NNS ,_, in_IN response_NN ,_, my_PRP$ own_JJ contribution_NN :_: a_DT verbless_JJ post_NN -LCB-_-LRB- the_DT first_JJ on_IN Language_NNP Log_NNP -RCB-_-RRB- ._. No_DT verbs_NNS at_IN all_DT in_IN this_DT book_NN of_IN Thaler_NNP 's_POS ,_, just_RB nouns_NNS ,_, pronouns_NNS ,_, adjectives_NNS ,_, adverbs_NNS ,_, prepositions_NNS ,_, subordinators_NNS ,_, coordinators_NNS ,_, and_CC --_: oh_UH !_. --_: interjections_NNS ._. All_PDT those_DT among_IN the_DT permissible_JJ -LCB-_-LRB- and_CC for_IN him_PRP ,_, past_JJ participles_NNS too_RB ,_, though_IN no_DT participial_JJ intrusions_NNS in_IN this_DT post_NN ,_, such_PDT the_DT extreme_JJ character_NN of_IN my_PRP$ cruel_NN and_CC unreasonable_JJ self-applicable_JJ strictures_NNS -RCB-_-RRB- ,_, but_CC never_RB one_CD single_JJ solitary_JJ verb_NN ._. And_CC ,_, fantastically_RB ,_, all_PDT this_DT a_DT vision_NN of_IN some_DT liberation_NN for_IN authors_NNS ,_, not_RB an_DT absurd_JJ literary_JJ straitjacket_NN with_IN the_DT writer_NN -LCB-_-LRB- albeit_IN willingly_RB -RCB-_-RRB- imprisoned_VBN within_IN it_PRP ._. Some_DT freedom_NN ,_, this_DT ._. Thaler_NNP :_: nuts_NNS ,_, bonkers_NNS ,_, round_VBP the_DT bend_NN ._. Mad_NNP as_IN a_DT March_NNP hare_NN ._. The_DT Liberman_NNP conjecture_NN -LCB-_-LRB- about_IN survival_NN of_IN high_JJ school_NN literary_JJ experimentation_NN into_IN adulthood_NN because_IN of_IN a_DT dysfunctional_JJ authoritarian_JJ French_JJ educational_JJ system_NN -RCB-_-RRB- :_: probably_RB true_JJ ._. My_PRP$ attitude_NN :_: contempt,_NN really_RB ._. Except_IN ..._: Unless_IN ..._: Just_RB possibly_RB ,_, an_DT exercise_NN ,_, for_IN the_DT undergraduates_NN in_IN my_PRP$ course_NN on_IN English_JJ grammar_NN this_DT fall_NN quarter_NN ._. An_DT effort_NN at_IN construction_NN of_IN fifty_JJ words_NNS of_IN coherent_JJ prose_NN with_IN never_RB a_DT verb_NN ,_, with_IN only_RB those_DT in_IN possession_NN of_IN enough_JJ grammatical_JJ knowledge_NN for_IN verb_NN identification_NN capable_JJ of_IN success_NN ._. Worth_JJ a_DT try_NN ,_, perhaps_RB ._. And_CC in_IN that_DT case_NN ,_, a_DT word_NN of_IN gratitude_NN to_TO Thaler_VB -LCB-_-LRB- otherwise_RB an_DT unimportant_JJ screwball_NN -RCB-_-RRB- ._. Always_RB that_DT extra_JJ possibility_NN :_: the_DT idea_NN justifiable_JJ not_RB because_IN of_IN its_PRP$ implementation_NN ,_, but_CC in_IN virtue_NN of_IN a_DT complementary_JJ or_CC counterposed_JJ idea_NN emergent_NN in_IN the_DT mind_NN of_IN someone_NN else_RB --_: serendipitous_JJ bastard_NN offspring_NN of_IN a_DT deranged_VBN cognitive_JJ parent_NN ._. So_IN my_PRP$ gratitude_NN to_TO you_PRP ,_, Thaler_NNP ,_, you_PRP pusillanimous_JJ poseur_NN ,_, you_PRP literary_JJ clown_NN ._. A_DT new_JJ idea_NN !_. My_PRP$ idea_NN ,_, all_DT mine_NN -LCB-_-LRB- accessible_JJ here_RB on_IN Language_NNP Log_NNP to_TO just_RB a_DT few_JJ thousand_CD close_JJ friends_NNS -RCB-_-RRB- ._. Ooh_NNP ,_, one_CD other_JJ thought_NN ,_, for_IN computational_JJ linguists_NNS :_: What_WP bets_VBZ on_IN the_DT performance_NN of_IN part-of-speech_JJ tagging_VBG algorithms_NNS on_IN prose_NN such_JJ as_IN this_DT ?_.
Here is a quick cheat sheet for those who have not yet memorized the Penn Treebank tagset (shame on you!):
CC Coordinating Conjunction CD Cardinal Number DT Determiner IN Preposition JJ Adjective -LRB- Left bracket NN Noun, singular NNP Proper Noun, singular NNS Proper Noun, plural PDT Predeterminer POS Possessive ending PRP Personal pronoun PRP$ Possessive pronoun RB Adverb -RRB- Right bracket TO to UH Interjection VB Verb, base form VBG Verb, past tense VBN Verb, gerund or present partciple VBP Verb, non-3rd person singular present VBZ Verb, 3rd person singular present WDT Wh-determiner WP Wh-pronoun WRB Wh-adverb
The Decipherment of Linear B by John Chadwick
In the year 1900, archaeologist Arthur Evans discovered several clay tablets at Knossos in Crete with writing in an unknown script. Civilization in Crete (named Minoan after its legendary ruler) was at the time (well before the late Bronze Age) more advanced than Greece. Legend tells of Athens' subjection to King Minos of Crete. The tablets of Minoan writing went through distinct historical changes: there was an early `heiroglypic' writing, then the script matured into pictorial signs called Linear A, which then was replaced by a modified form called Linear B. This book is the story of how the tablets in the Linear B script were read.
The Minoans were not Greek and spoke the Cypriot language and so the established hypothesis was that there was some relation between Linear A and B and the Cypriot script. The Cypriot script did play a role but amazingly enough, an outsider to the field: Michael Ventris, showed using some novel cryptographic techniques (described in detail in this book) that the language in Linear B was in fact a Mycenaean dialect of Greek.
Chadwick an early supporter of Ventris explains the method and the results in accessible detail. Some of Chadwick's early discussion of the background is quite muddled, which is unfortunate since this book is best single source for this information. The decipherment process itself as documented here is an intellectual treat.
Also amazing is the story of the decipherer: Michael Ventris. Born in 1922, he studied to be an architect in London and after earning his diploma worked on the design on new schools. Meanwhile, in 1952 he claimed to have discovered the key to the Minoan script (amazingly the first decipherment of the Mayan script also occured in 1952, see "Breaking the Maya Code"). Since he was an outsider to the field, and his views were contrary to the academic establishment his views were vindicated by his peers only by 1955. Soon after his theory became accepted, while driving home alone one night his car collided with a lorry, and he was killed instantly. He was 34 years old.
This book is a lite version of the book John Chadwick co-authored with Michael Ventris called "Documents in Mycenaean Greek" (Cambridge University Press, 1956).
%T The Decipherment of Linear B %A John Chadwick %I Cambridge University Press %D 1958 %G ISBN: 0521398304 %P 164 %K science, linguistics
Review written: 1999/08/09
May 11, 2004
Breaking the Maya Code by Michael D. Coe
Like a lot of good science books, this book is a good detective story. The ancient Mayan language in written form was found on several ruins in South America in the 18th century but these inscriptions were not read until the 1950s. This book is the story of this decipherment. The subject matter of writing systems and Mayans is quite a challenge to present in a pedagogically sound way, but Michael Coe is thankfully competent enough to tell this story. And he tells it very well indeed.
Coe's introduction to writing systems in general (in Chapter 1: The Word made Visible) is extremely well written. As an aside: for some new work on the topic of writing systems there is a book coming out in 1999 by Richard Sproat ("A Computational Theory of Writing Systems": Cambridge University Press) which tries to give a general theory that covers all known writing systems.
Coe also gives a reasonable insight into the ancient Mayans (he also has another book devoted entirely to this subject) although reading up on the Mayans before reading this book is perhaps a good idea (if you haven't already suffered through several idiotic documentaries about the Mayan astronauts).
There are many surprises in the story (as it should be in a good detective story). It is inconceivable that scholars for more than 200 years preferred theories about the Mayan language involving mythical lands such as Atlantis rather than accepting that the people living there now spoke essentially the same language as the Mayans. Even more surprising that although the ruins were discovered in the late 1700s, only in 1952 the first beginnings of a real decipherment was accomplished by Yuri Knorosov in an article published in `Sovietskaya-Etnografiya' (despite Stalin's stifling influence on the content of this and other journals of the time).
Further reading in this topic includes "Understanding Maya Inscriptions: A Hieroglyph Handbook" by John F. Harris and Stephen K. Stearns and "The Decipherment of Linear B" by John Chadwick.
%T Breaking the Maya Code %A Michael D. Coe %I Thames and Hudson %D 1992 %G ISBN: 0500277214 %P 304 %K science, linguistics
Review written: 1999/08/04
May 09, 2004
Permutation City by Greg Egan
The blurb on the back of the book proclaims it to be a book about virtual reality. This is misleading: its about more than just another stereotypical cyberpunk retread.
Artificial life, cellular automata, Turing machines, aliens that are not alien at all, the anthropic principle and some metaphysics about solipsism are thrown into the plot for good measure.
Greg Egan is most comfortable playing with speculative physics which he combines here with extrapolations about self-replicating software. Greg Egan's personal web site contains Java applets (!) to explain his more mathematical speculations. His later novels such as "Diaspora" and "Schild's Ladder" are very similar in their indulgence in his special brand of speculative physics and healthy contempt for those who dislike the addition of mathematical recreations to fiction.
Some of the ideas here have been explored by Greg Egan in some of his short stories. For example, the virtual reality parts of this book have been used in "The Kidnapping" (in his short story collection "Axiomatic"). And his `Dust' theory has also been explored in an earlier short story.
Update 2004/05/18: A lot of the material is drawn from the various uses of cellular automata in models of complex systems in physics, such as those associated with the Santa Fe institute on the study of complexity. These models have appeared in sf before, e.g. "Moving Mars" by Greg Bear (published 1993). However, in this novel Greg Egan turns this set of models into generative devices and as such the ideas in this novel might actually prefigure the discussion in Wolfram's book about the relevance of cellular automata in particular and computer science in general to all fields of scientific inquiry. In fact, Greg Egan has written a review of Wolfram's book (also on his personal web page).
Link: Greg Egan's web page. (Warning: loads up some Java applets).
%T Permutation City %A Greg Egan %I HarperPrism %D 1994 %G ISBN: 006105481X %P 340 %K science-fiction
Review written: 1999/08/04
May 06, 2004
Special Circumstances Migrates To Movable Type
Lost Moon by Jim Lovell and Jeffrey Kluger
Pure lunacy. The story of getting a crippled spacecraft headed for the moon back to earth safely.
Reading about the Apollo 13 disaster in this book strangely had the opposite effect to what I was expecting. The story is not about heroism or miracles but rather about training, design and expertise which surprisingly turns out to be much more interesting.
This is a must-read for anyone interested in space travel since few other books describe it in such fascinating detail. Even though Jim Lovell is one of the authors, the presentation is in the third person since there are many viewpoints from which the story had to be told. So it is less of a memoir and more of an honest journal of the events (although there is a great story about Lovell in his early days trying to dead-reckon his way at night without instrumentation onto the deck of a carrier). In fact, the astronauts were (understandably) petulant during most of the trip home often losing their patience with the ground crew. Also interesting is the fact that amateur astronomers would try and pin-point the location of the Apollo spacecraft by trying to locate condensed urine streams.
Of course, most people since the release of the movie about Apollo 13 will not consider reading the book. The movie does help in visualising many details about the spacecraft, but the details in the book were not reflected in the movie. Also, there were many places where the movie where the facts were distorted, I assume, for dramatic effect. Ken Mattingly, the astronaut who was not allowed to fly due to a predicted attack of the measles is given a much larger role in the movie at the expense of the real people (John Aaron and Arnie Aldrich) who solved the problem of powering up the command module.
%T Lost Moon %T :The Perilous Voyage of Apollo 13 %A Jim Lovell %A Jeffrey Kluger %I Houghton Mifflin and Company %D 1994 %G ISBN: 0395670292 %P 378 %K science, spaceflight
Review written: 1999/07/20