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Computer Program Detail Page

Item Picture
Simultaneous Events Program
written by Kiril Simov and Wolfgang Christian
The Simultaneous Events program displays the effect of relative motion on the relative ordering of events in special relativity.   In the default scenario two simultaneous events are observed in a stationary reference frame (the Other Frame) and the spacetime diagram of the observation of these events is depicted in another reference frame (the Home Frame).  The slider can be used to change the relative speed between the two frames.

Simultaneous Events is an Open Source Physics program written for the teaching of special relativity.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the sr_simultaneous.jar file will run the program if Java is installed.  Other special relativity programs are also available.  They can be found by searching ComPADRE for Open Source Physics, OSP, or Relativity.

Please note that this resource requires at least version 1.5 of Java.
Subjects Levels Resource Types
Classical Mechanics
- Relative Motion
= Moving Reference Frames
- Reference Frames
- Spacetime Fundamentals
- Special Relativity
= Simultaneity
- Lower Undergraduate
- Upper Undergraduate
- Instructional Material
= Interactive Simulation
Intended Users Formats Ratings
- Learners
- Professional/Practitioners
- Educators
- application/java
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Access Rights:
Free access
© 2008 Wolfgang Christian
Additional information is available.
OSP, Open Source Physics, events, inertial reference frames, reference frames, simultaneity, simultaneous, spacetime diagram, special relativity
Record Creator:
Metadata instance created May 23, 2008 by Mario Belloni
Record Updated:
May 12, 2015 by Wolfgang Christian
Last Update
when Cataloged:
May 1, 2008
Other Collections:

Possible bug in the simultaneous events program

Author: Duncan Galloway
Posted: April 29, 2015 at 5:27AM

we have been using the simultaneous events program for some years, and have noticed what appears to be a minor bug. The gradient of the world line does not agree with the 1/v that we expect. It is actually measurably steeper.

For example, with beta=0.5, the world line beginning at the left (i.e. the left end of the rod) passes through the points (-0.5,0.83) and (0.,2.03), indicating a gradient of 2.4, where it should be 2. Here is a link for an illustrative diagram: https://dl.dropboxusercontent.com/u/12977207/simultaneous.jpg

This does not seem to be a platform issue, as we've experienced it on both Macs and Linux desktops. I hope you can suggest a workaround or solution


» reply

Re: Possible bug in the simultaneous events program

Author: Wolfgang

Thanks for point out the error in Simov's model.  I will try and fix it this summer.  In the meantime, you can use the following.


» reply

Re: Re: Possible bug in the simultaneous events program

Author: Wolfgang

Bug in worldline slope has been fixed.

» reply

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ComPADRE is beta testing Citation Styles!

Record Link
AIP Format
K. Simov and W. Christian, Computer Program SIMULTANEOUS EVENTS PROGRAM, Version 1.0 (2008), WWW Document, (https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410).
K. Simov and W. Christian, Computer Program SIMULTANEOUS EVENTS PROGRAM, Version 1.0 (2008), <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410>.
APA Format
Simov, K., & Christian, W. (2008). Simultaneous Events Program (Version 1.0) [Computer software]. Retrieved July 23, 2024, from https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410
Chicago Format
Simov, Kiril, and Wolfgang Christian. "Simultaneous Events Program." Version 1.0. https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410 (accessed 23 July 2024).
MLA Format
Simov, Kiril, and Wolfgang Christian. Simultaneous Events Program. Vers. 1.0. Computer software. 2008. Java 1.5. 23 July 2024 <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410>.
BibTeX Export Format
@misc{ Author = "Kiril Simov and Wolfgang Christian", Title = {Simultaneous Events Program}, Month = {May}, Year = {2008} }
Refer Export Format

%A Kiril Simov %A Wolfgang Christian %T Simultaneous Events Program %D May 1, 2008 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410 %O 1.0 %O application/java

EndNote Export Format

%0 Computer Program %A Simov, Kiril %A Christian, Wolfgang %D May 1, 2008 %T Simultaneous Events Program %7 1.0 %8 May 1, 2008 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=7237&DocID=410

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The AIP Style presented is based on information from the AIP Style Manual.

The APA Style presented is based on information from APA Style.org: Electronic References.

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Simultaneous Events Program:

References Six Ideas that Shaped Physics

We have adopted the same terminology for the Home and Other Frames as Thomas Moore's Six Ideas that Shaped Physics book on special relativity.

relation by Mario Belloni

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