



WAVE MECHANICS De Broglie Comptes rendus 1923 note, with permission. Phase wave animation. 
DEADLY DESIGNS Active infrared (IR) sensors for swinging doors. 
EXPERT WITNESS Do you need an expert witness for an automatic door case? 

EINSTEIN PHOTOGRAPHS A portfolio of photographs of Albert Einstein at Princeton University taken by Lotte Jacobi. 
RELATED LINKS Links to door and sensor manufacturers, standards, etc. 
REVOLVING DOOR KINETIC ENERGY Free Revolving Door kinetic Energy Calculator program (RDEC). Verify compliance with ANSI A156.27 national standard. Manual and FAQ included. 

GRAVITATIONAL RADIATION Gravitational radiation in the Einstein, BransDicke and Rosen bimetric theories of gravity. 
REVOLVING DOOR STANDARD FLAWED Kinetic energy equations in ANSI A156.272003 in error. Learn more. 
REVOLVING DOOR DEFECTIVE DESIGN Kentucky appellate court affirms finding of revolving door defective design; absence of leading edge sensors. 



DRAGON CURVES What is a Dragon curve? Download a plot of four interlocking Dragon curves, and free Dragon curve software. 
RMFTL SOFTWARE RMFTL^{TM} Roworiented Multidimensional FFT Library. 

PYTHAGOREAN THEOREM See the Pythagorean Theorem proven painlessly right before your eyes via animation. No mathematics required! 
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