Sunday, October 9, 2022

Swiss Micros DM42: Time Dilation

Swiss Micros DM42:  Time Dilation 



Introduction


The program DILATE calculates the time passage from the traveler's perspective:


t' = t * √(1 - (v/c)^2)


where c = Speed of Light = 299,792,458 m/s


We can also state the equation as:


t' = t * cos(arcsin (v/c)) 


because cos(arcsin(x)) = √(1 - x^2) for |x| ≤ 1



Why cos(arcsin(x)) = √(1 - x^2)?


Let Θ = arcsin x.  Then x = sin Θ.  Assume that -1 ≤ x ≤ 1.


From the trigonometric identity:


cos^2 Θ + sin^2 Θ = 1

(cos Θ)^2 +  (sin Θ)^2 = 1


With sin Θ = x,


(cos Θ)^2 + x^2 = 1

(cos Θ)^2 = 1 -  x^2

cos Θ = √(1 - x^2)

cos(arcsin x) = √(1 - x^2)



Swiss Micros DM42 Program:  DILATE

Also:  Free42, Plus42


00 {52-Byte Prgm}

01  LBL "DILATE"

02  "TIME?"

03  PROMPT

04  "VEL (M/SEC)?"

05  PROMPT

06  299792458

07  ÷

08  ASIN

09  COS

10  ×

11 "T'= "

12  ARCL ST X

13  AVIEW

14  RTN

15  END



Example


A spaceship traveling at a velocity of 186,000,000 m/s (about 416,070,150 mph) for 1 year from our perspective.


XEQ DILATE

TIME?  1

VEL (M/SEC)? 186000000

 

Result:  0.78426 year would have passed on the spaceship, which is about 9 months and almost 13 days


Until next time,


Eddie 


All original content copyright, © 2011-2022.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author. 


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