Ken Halpern's Home Page


PLEASE NOTE: This page is very very very old. It predates blogs. It predates the internet. It predates language. Which explains a lot. Feel free to try it, but the links probably are broken, the jokes bad, and the beer stale. I'd really suggest the new place across the street:

There the links work, the jokes are fresh, and the beer is great. And I probably, mostly, kind-of don't get any kickbacks. But for those who don't know how to take good advice, here's my old site...


*** Visit my new Zine Involutions ***

You've reached Ken Halpern's home page.  I am a particle physicist with interest in most areas of scientific and/or creative endeavor.  This page is designed to serve as a centralized bookmark list for personal convenience.   Some of the links reflect active or potentially active interests, while others point to novel or useful sites.  The criteria for inclusion are (a) I have visited the site, through referral or random peregrination and (b) I believe that I will wish to revisit the site in the future.  This is a pompous way of saying that this page is whimsical and follows no rhyme or reason.  The design of the page required deep artistic consideration.  It is based on an obscure but popular school of aesthetic thought.  Every motif, color and font was chosen based on the maxims of this philosophy, a system which emphasizes substance over form.  Although a lay person may not be expected to understand its subtle underpinnings, they may be summarized as: "I'm too lazy to make this page purdy."   If you are a visitor, then you will hopefully find some interesting links. If you are me, then you are talking to yourself and should seek psychological counseling.  Happy Surfing.


Learning:  Physics, Math, Biology, Cognitive Science, Information Theory, Computer Science, Articles and Books
Other Interests: Writing, Composition, Problems
Gear/Shopping:  Books, Surplus, Telescope, Microscope, Photo, A/V, Music, Swords, Outdoor, Tools, GPS, Aquaria, Video Games, Computer, Misc, Land
News/Reference:  News, Online Services, Reference, Software, How To
Living:  Local, Movie, Clubs, WW, Catskill
Activities/Living:  Diving, Hiking, Bicycling, Kayaking, Vacation, General
Trips:  Recent Trips, Other Photos/Logs, Day Hikes/Trips, Future Plans
Misc:  Gear, Clothing sizes
Notes from Books
Learning:  Notes, Essays, Scanned Notes, Topics to Study
Lists:  Books read, Books owned, To read, Recommendations, Stereo, Gear, Useful info



Main LANL Page Links to many subjects
LANL Weekly Hep Theory Entries for the last week
LANL Paper Submission Help Author's Guide
Spires HEP Page Still the standard
My Papers on Spires Remembering the glory days (or something)
Theoretical Physics Job Rumor Mill This is a great site to catch up on friends in theory.
APS American Physical Society.  I'm a member.
AIP American Institute of Physics (publishes books and journals)
Annotated Physics Encyclopaedia
QFT Books Online List of lecture notes and books online
Physical Review Online


Cornell Digital Math Library An excellent library of online math books
AMS American Mathematical Society. I'm a member. Has good books for sale.
Courant Institute Journal List List of math/physics online journals
MAA recommended books Designed for libraries, but useful for picking the best books on a subject.
Clay Mathematics Institute Offer prizes for key unsolved problems
MIT math dept textbook list
John Baez' Homepage Lots of interesting articles and problems
Atlas of Finite Group Presentations
NIST Digital Library of Mathematical Functions page (in progress)
Topology Atlas : Good database and set of links
Knot Theory Page : Lecture Notes and links
PlanetMath : Large forum and encyclopedia of math under GNU license
MathWorld : Eric Weisstein's World of Math (supported by Wolfram)
Online Books and Notes in Math : Good list
Category Theory References List
AMS Math Subject Classification
Peter Woit's Homepage Interesting articles on QFT and math
The Knot Theory Ma3F2 Page
Ravi Vakil's Homepage Lots of articles, lecture notes


Kyoto Encyclopedia of Genes and Genomes Nice site
Origins of Life page Contains journal listings in 1999. Not updated recently.
AIBS Online Library
Origins of Life Journal

Cognitive Science

Journal of Cognitive Science Multidisciplinary journal
CogPrints Cognitive Science Papers Archive

Information Theory, Complexity, and Cellular Automata

Cryptography page Interesting discussion of cryptography (and random number gens)
Theory of Compression A decent discussion
Biological Information Theory and Chowder Society FAQ Looks interesting Cellular Automata information page
Kolmogorov Complexity PageMany references and a mailing/news list
Chaitin's Homepage Contains many publications
Publications of Ray Solomonoff : Key Figure in Complexity Theory
Jurgen Schmidhuber's publications : Complexity Theorist
Information Content FAQ Has good discussion of why Kolmogorov Complexity isn't absolute
Information Theory Links A good list of application topics
Video and Audio Compression A discussion of various methods

Computer Science

Knuth's Surreal numbers : An interesting discussion of this bizarre idea
Online Design Book : An excellent book about programming design patterns
NEC ResearchIndexAn excellent database of journal articles
NIST DADs Dictionary of Algorithms and Data Structures

Online Articles and Books

MIT notes for 8.962 GR Not entirely complete
An Exposition on Inflationary Cosmology - Watson Good survey
Introduction to QFT Online book by Fedorov
MIT notes for 18.325 applied math
Algebraic Topology Book - Hatcher Hatcher's Excellent book, online and free
Differential Geometry Notes (Csikos)
Differential Topology Notes by Brin at Binghamton
Summary of Spivak Books : Concise notes
Shannon Paper The original paper by Shannon
Topics in Kolmogorov Complexity Lectures by Ran El-Yaniv
Lambda calculusA good article on the lambda-calculus (with examples in perl)
Article on Mathematical Theory of Computation
Numerical Recipes On-line Free online versions of recipes in Fortran and C and lots of other stuff
Stanford Encyclopedia of Philosophy Entry on Category Theory
Differential Structures in Physics Book by Abelmeyer and Brans
Geometrical Methods in Physics Lecture Notes from Rajeev
An Exposition on Inflationary Cosmology Article by Watson
Kolmogorov Complexity Course by Shen in Moscow
Poisson Bracket Article
Poisson Brackets and Sympectic Forms
Structure and Interpretation of Classical Mechanics Article by Sussman
Article on Automated Theorem Proving in Mechanics
Outline of Synthetic Differential Geometry Article using Categories by Lawvere
Shreve's Lectures on Stochastic Calculus
Mathematics of Boolean Algebra Stamford Encyclopedia article
Boolean Algebra Good article
Books and Articles by Wolfgang Luck
Triples, Toposes, and Theories Full Online book by Barr
2002 Advanced Complexity Theory MIT Lecture Notes (6.841)
Algebraic Topology Article from Mathematical Atlas
2001 Advanced Complexity Lecture Notes>MIT (6.841)
2003 Advanced Complexity Lecture NotesMIT (6.841)
Bernoulli ShiftDescription and Demo
Factorial Design Description of the experimental technique
Introduction to Algebraic Geometry Lecture Notes
Breaking Lorentz Symmetry Simple article
Differential Analysis Lecture Notes MIT 18.155

Book Hunting

Abebooks The direct link to their great search engine
Bibliofind Now it's just Amazon. Blah.
Book Sales in America Site tracking library sales in america. Very useful, but watch out for advertising.
Alibris I prefer abebooks, but haven't used these guys recently.
Bookfinder Meta Engine Pretty good
Used Booklover's Guides online An awesome tool for finding used bookstores when traveling
Bookstores in the UK A useful directory (London)
US Government Printing Office Buy donated books from libraries


Sun Divers Diving company run by Steve's Brother and Sister
PanAqua Diving Very good store and list of trips
PADI Diving certification organization


Outdoor Bound Have Hiking day trips in the spring through fall
The Camper's Group An interesting looking NYC camping group
Sierra Club NY Outings I'm a member. Day trips and weekend trips
Appalachian Mountain Club (AMC)   I'm a member. More serious than Sierra club. Lots of politics and fighting
Adirondack Mountain Club I'm a member. 
NY-NJ Trail Conference I'm a member. Publish local trail maps.
TrailMonkey Free online maps


Five Borough Bike Club I'm a member. They usually won't respond to Emails
New York Cycle Club I'm a member.  More intense than the 5bbc


Downtown Boathouse Offers free Kayaking lessons on Weds
Zoar Outdoor Excellent Kayaking instruction in Berkshires
Clarke Outdoors Kayaking instruction in CT

General Outdoors and Activities

Martinez Academy of Arms  Real swordsmanship, not just fencing.
NY Aikikai According to rumor, they have a direct disciple of Morihei Ueshiba teaching.
NY Sports Online - Tennis Guide to Tennis Courts in NY
NY Sports Online Guide to Sports in NY
MidTown Tennis Cheap lessons, but clay court
Manhattan Plaza Health Club Tennis and Rock Climbing
Aikido of Manhattan : More traditional that NY aikikai
Amateur Observers' Society of NY  Listing of outings
Sky & Telescope listing of NY area clubs
TrailMonkey Free online Maps

Vacation Ideas

Sierra club trips A bit pricey, but seem interesting
REI trips Some of these look great
WhyTravelAlone  Find compatible traveling companions
Travel Ratings Airlines, etc.
OutdoorGuide Outdoor website
Getoutdoors Another outdoors website.
C-N-Do Scottish Hiking Tours Cheap tours. Very good.
Costa Rica Hiking Interesting looking tour company
Infohub Specialty Travel Online list of trekking resources
National Geographic Trips More expeditions
Budget travel worldwide hiking
Day hiker
Civilized Explorer
Medjet Evacuation service for exotic locations (annual fee)
NOLS Run outdoor training and leadership courses. Highly recommended to me.

Scientific Surplus

Sam's Laser FAQ Great informational page.
Meredith Instruments Reseller.
Surplus Shed A good supply house
Information Unlimited Are these guys legit or are they crackpots?
LabX Directory of Surplus Dealers on Web
All Electronics Corp. Good surplus place. Peltier junctions, some lasers, lots of cool stuff
Index of Electronics Sellers A useful listing
American Science and Surplus Another surplus store
Carolina Biological An excellent (but expensive) source for most supplies. Obnoxious policy for chemicals.
Edmund Scientific Good store. Links to both the "scientifics" and optics stores Surplus Supply house
San Jose Scientific Large supplier. Will sell chemicals


ScopeReviews Ting's Amazing Telescope sight. Check out the ranking Matrix
AstroMart Great Used Telescope Classifieds and Directory of Web Sites
APM-Telescope Large directory of telescope web sites
Cloudy Nights Some Telescope Reviews
Excelsis Consumer Reviews of Telescopes : Good listing
WinCTC Tracking system


DP Review Digital Camera review website. Excellent
Ikelite Make good underwater camera cases
Steve's Digicams Good review site
CKC Power Produce lens adaptors, etc for digital cameras (like s100)
Cameras UnderWater

Music Composition

Music Link Page Great list of links to software, hardware, etc music sights
Listing of Music Software Available A comprehensive guide

Musical Instruments and Synthesizers

CD Sheet Music Classical sheet music on CD. Excellent
The Synth Site Great database of synthesizers.
Harmony Central Synth Database Another good synth database.
Info on Korg 01/W PCM Cards Descriptions of the various PCM cards
Sound on Sound Magazine An excellent source for synth info
Classical Net Recommended recordings, etc


New York Times
Christian Science Monitor
Fox News
The Onion Spoof of news. Comes out on Wed.
Wall Street Journal By subscription only
Consumer Reports
Village Voice Good for Apartment Hunting  Excellent articles on world affairs and military analysis
Journal of the AMA Excellent. Lots of free medical info.
World Policy Journal Interesting articles (many of which are free)
McKinsey Quarterly Excellent Business Cases and Articles
The Economist Good, but magazine is better.

Video Games (yes, I'm a nerd)

Gamewinners Strategy guide search engine for all games on all systems.
The UnderDogs Provide PC games that are no longer copyrighted
Mame  This is an arcade emulator for almost every arcade game out there.  Free.  Roms available here too
VideoGameReview Yet another review site (PS2).
Vice Documentation Man pages for the c64 emulator VICE


Pet-Expo Cheap Incandescent Lighting
American Hobby Supply Excellent CF DYI fixtures
All-Glass Aquaria Make mini-reefs
AquaDirect Good Prices on Skimmers
CPR Makers of CPR MRT micro-reef tank
Tenecor Makers of All-in-one microreef tanks
Thiel Database Extremely large reef aquarium resource (general reefs) Excellent resource for nano-reef info. They make micro-reefs too.
Jellyfish Article on

Puzzles and Problems

Cool Physics Problems Cool Physics Problems
Paul Hsieh's Puzzles Fun brainteasers
Putnam Exams 1985-2000 (problems) and 1995-2000 (solutions)
Math competitions on the web Lots of links
Putnam Page Links to putname info
U of Missouri Math Problem Archive Huge.
Another putnam page (1993-2000)
Rec.Puzzles Archive
IBM Ponder This Monthly Problems
Jaap's Puzzle Page Physical Puzzles
Another Putnam Archive
U Oregon PhD Qualifying Exams
Washington U Physics Qualifying Exams (part 1)
Washington U Physics Qualifying Exams (part 2)
Harvard Math Qualifying Exams
Duke Physics Qualifying Exams


IPS Imaging Some amazing deals on used microscopes
Molecular Expressions A comprehensive discussion of photomicrography (emphasizing polarized viewing of chemicals)
MicroscopyU Nikon site. Also molecular expressions. Has small world competition
Conneaut Lake Scientific Surplus microscope equipment, etc.


Swords-n-Stuff A cool seller of swords and daggers. Annoying Flash site.
Bright Blades Another cool seller of swords
Sword info Page Very informative
Sword Metallurgy Excellent essay on the metallurgy of swords
Mount Valley Forge 500 layer blades. I've got to get one of these
SwordForum Magazine link list A magazine for sword enthusiasts
Bullwhip Page Not swords, but close enough.

Hiking Gear Good hiking gear review site. GPS too.
The Gear Store Another gear freak site. Excellent user review site
Wanderlust Gear Ultralight (but pricey) gear

Tools and Equipment

Power tool reviews Useful reviews


Moviefone Online tickets (except for AMC theatres)
Movietickets Online tickets for AMC theatres
Fandango Online tickets for all theatres
IMDB database Excellent database of american films
Rotten Tomatoes Reviews The only review site necessary. Sometimes, need to link via imdb
Mr Cranky Reviews Sometimes quite amusing
DVDJournal MIA List DVD Releases and Wish List
Shaw Brothers' Movies This site sells an increasing number of these kung fu movies on DVD.
Quicktime Trailers For many movies Excellent lists of blunders for many movies
Video Graveyard Over 1100 video reviews (horror?)

Cool Stores

Bigelow Teas Love their Earl Grey.
AmericanX Good Hibiclens Prices
Meffert's Puzzles Very cool puzzle place in Hong Kong
Brodart Library supply Plastic book covers and other stuff
University Products Plastic book covers, etc. No online catalog yet.
ICD Chess Large game store (includes other games too)
Fountain Pen Hospital Best Store for Fountain Pens Cool science toys
ICD Chess Game store
Funagain Games Game store with EXCELLENT prices


Directron Lots of silent PC supplies
New Egg Excellent for PC parts
Tom's Hardware Excellent computer hardware review and benchmark site
Reseller Ratings Ratings for computer resellers online
Roundup of 80mm Fans

Shareware The definitive source for all palm software.
DisplayMate A Useful Tool for Calibrating Monitors
Csound homepage
Common Music A very interesting music language
Adsubtract Freeware to subtract banner ads from web pages.  Very good.
Xemacs For windows
Active Perl For windows
Winshell  Good Tex Editor for windows
MikTex Excellent full tex implementation for windows.  Includes yap (xdvi)
SimTel Massive PC (and other) file archive
Sourceforge Huge database of freeware programs and projects (including obscure ones)
GNU homepage List of all their projects,docs, etc
Root Powerful Freeware Statistical Package from CERN
Povray Powerful Freeware Ray Tracing Package
Fractint Poweful Freeware Fractal Package
Software links on the web
Piclab Amazing freeware picture editing program. I think this is the correct one.
gTybaltFreeware symbolic math program. In early stages.
CTAN The primary TeX archive site
Irfanview Excellent freeware photoshop
Earmaster Excellent eartraining program. Shareware with trial period. A bit buggy.
GNU LilypondMusic Typesetting Program
Yacas Yet Another Computer Algebra System
Scilab Matlab emulator
Lapack reference page
Matrix Template Library New project to wrap BLAS and Lapack. Looks promising
Open Science Project Extensive List of Opensource Scientific Software
Fractal Links A comprehensive list of software
LyX for Windows Front End to LaTex
PC Magazine Utilities Shareware
Zoomplayer Useful DVD playback wrapper. Very powerful, and free.
Powerstrip Program to allow custom video modes (for projectors, etc).
MetaMath Automated Theorem proving software
LPAC Lossless compression of audio files
Chemdoc Chemical typesetting package for tex
Math packages for Excel Freeware to perform matrix calcs
R Open Source Statistical Package based on S
eLVis Linux Video Surveillance Software
Motion Linux Video Surveillance Software
ZoneMinder Linux Video Surveillance Software
Gspy Linux Video Surveillance Software

NY Living

Lincoln Center Poorly organized
Central Park activities Sometimes list concerts and plays Upper west Side Good for apt hunting
TimeOut NY Guide to Happenings in NY
Dizzy City Has VR views from every street corner in Manhattan
NY Transit MTA, Metro-North, LIRR Train schedules
Parking Forms for Manhattan For parking tax refund
Local Weather for my area Weather Channel
Local Weather for my area AccuWeather
NYC Street Conditions Lots of info about street closures, parades, construction, rules, etc
NY Library map and Hours
NY Library search engine.
Bryant Park Movie schedule
SFWA List of moderately priced midtown restaurants
Amazon Restaurant List Comprehensive menus for many restaurants in the city
1010 Wins : Good source for local info and news
CraigsList NYC Menu listings for NYC


Weather Channel - Catskill
Accuweather - Catskill
Want Ad Digest
Cementon USGS Quad
Town of Catskill

Online Services (nonlocal)

DealCatcher Lists most current internet discounts, etc.  Check out forums/coupons
TechBargains A very good coupon site for tech deals
FatWallet Another bargain finding site
PriceWatch Price Comparison for Tech stuff
PriceScan Price Comparison site
Big Yellow Pages Not so great
White Pages I've never had much luck with online white pages
Reverse phone search There still is one!
Geographic yellow pages Very useful radius search
Google Search engine
Altavista Search engine
Windows Media Radio Station Listings Lists all programs on all radio stations
Mapquest Ordinary maps on the web
Ubid Auction site where you bid downwards.
Dynamic DNS Service
Seat Guru Describes the best seats on various airplanes
Broadband Like dealcatcher. Very good but needs signon

Universities and Clubs

Columbia University Library Hours, etc
Society of Quantitative Analysts Finance organization Pretentious Ivy League snobbery (but, I'm a member)

Weight Watchers

Weight Watchers Fast Food Points Fast foods
Weight Watchers Formula and Points Very Good site


Literary Magazine Index By Random House (but lists all publishers). Extensive.
Roget Thesaurus Project Attempt to build an online thesaurus with cross-refs, etc
Common Error's in Language Grammarian website
Writer's relief Excellent website for writers List of writing contests
Writer's Market Scifi and Fantasy List of magazines and publishers

Audio and Video

Audiogon Audiophile auction and classified site
Audioreview Audiophile review site. Excellent.
Chesky records Famously high quality recordings
AVS Forum Main site for home theater info and discussions
DIY Audio Site dedicated to DIY audio projects
Building an HTPC (part 1) Good article
Some HTPC advice regarding windows XP
Best in Class HTPC parts Suggestions for best choices of HTPC at different price levels
Parts Express Excellent source for AV and other parts
Progressive DVD Player Shootout
Silent PC Review Dedicated web site


OnlineBooks Archive of Free Online Books
MIT Open Courseware Major open courseware initiative
SSRN Electronic Library Excellent searches for Finance papers
Usenet Faqs The faqs for all major news groups
PhDs org Career resources
Graduate school directory in physics
Unit conversion page
Online Medieval & Classical Library Many texts online (Berkeley digital library)
Paleta On-line art project containing 100's of photos of famous paintings

Stanfored Encyclopedia of Philosophy
List of online texts in math/physics From Google
Kennedy School CaseWeb Case Studies
Sacred Books of The East Online Versions
Supreme Court Decisions
Ramayana and Mahabharata Online versions
Strong Signals Bandplan List of US radio bands
NYC Scanning Frequencies
Horror Masters Online versions of the classics. Very good, but can't print or save
Aardwolf Games Database of games and rules


Snopes Urban Legends debunked (try too)
Bed and Breakfast locator Can be useful (maybe)
Search Congressional bills Keep tabs on Uncle Sam
EFF Organization Protects Electronic Freedom
Do-Not-Sleep Lots of silly diversions
Consumer Protection Board for NYS Contact to block telephone solicitations
Death toll page Contains lists of major violent events throughout history with extensive references. An excellent page.
People for the American Way Watchdog organization
Science Projects Some cool science projects
US Frequency Allocation Chart Government allocation of the spectrum Amateur railgun project
Explanation of the Anomalies of Water Many interesting physical properties Corporate Watchdog Organization Voice and speech trainers association
Piano Bluebook
Cilling Effects ClearinghouseHow to deal with those pesky DMCA lawyers
Supreme Court Docket
NARA Federal Register Historical Electoral College info
GasLight Online Texts

How To
Online Tex Manual "A Gentle Introduction to Tex"
Cursive Handwriting Page Has templates for practicing penmanship
Guide to setting up a web server FreeBSD server config Article on Soundproofing Apartments. Warning- they try to sell stuff too
Foolproof noiseproofing Another article on keeping out noise
Using An Oscilloscope Informative article
Xinetd reference
Making Tex WorkFull text of O'Reilly Book
SSH Reference
NY DMV Motorcycle Manual
Scanning Tunneling Microscope Construction Kit
SS64 Guide to Windows NT commands
Linux Security Linux Equivalents How to convert from Windows
Video 4 Linux Resources

Topozone Topographic maps on the web
MapTech An extensive map server
GIS Data Depot Free USGS data, etc in raw file formats
GPS Waypoint Registry Massive Database of GPS waypoints
GPS Resource Pages Lots of useful links
Creating Custom Garmin GPS Maps Describes how to do so using freeware and lots of time
Joe Mehaffey GPS Site Amazing GPS page

NYS GIS Clearinghouse USGS (1:24K quads)
NYS GIS Orthoimagery application
Yahoo Neighborhood Research Very useful
Due East Real Estate Broker : Maine waterfront
Christmans Associates Broker : Adirondacks
Land And Broker : All over
John Cochrane Broker : Maine
Maine Land 4 Sale Search (broker or MLS?) : Maine
Everett Worcester Broker : Maine (wrote a book)
Search (broker or MLS?) : Adirondacks
Drop Anchor Realty Broker : Maine
David Knudsen Broker: Sullivan County. Lots of useful info.
Nutshell Realty Ulster County MLS Search
Greene County MLS Search
Li Daniels Another Ulster County MLS Search
Glebus Realty Broker : Adirondacks
Adirondack Country Homes Broker : Adirondacks
American Wilderness Broker : Adirondacks and NH (for hunting tracts)
Yahoo list of Adirondack Realtors
First Catskill Broker : Catskills

Trips and Photos

Scotland 2002
AMC Adirondack Trip, Labor Day 2002
Hawaii 2002
Cancun 2002
Cozumel 2002
Grand Canyon Trip 2001
Montauk 100 (Metric)


Thanks to for their counter!