Talk:Special relativity and steps towards general relativity

Latest comment: 5 months ago by Boud in topic Feasibility of videos

Use in a bricks-and-telescope university




The freely licensed material for this Wikiversity course has been used in a real-life, "bricks-and-telescope" university during the northern summer semester of 2011. It is quite likely to be used again from Feb to June 2012.

The June 2011 version of the course can in no way be considered to be sufficient as an "introduction to GR"; at most, it provides a few steps towards an introduction to GR. The WIMS exercises provided significantly underuse the teaching power of WIMS: clickable spacetime diagrams and clicking to create parts of spacetime diagrams should be added as part of the SR exercises; maxima should be used as a backend so that exercises allowing students to be tested using elementary algebra, differential calculus, componentwise tensor calculations and intrinsic tensor calculations can be added.

Once the initial version of the course has been fully uploaded, the free licensing of the lectures and exercises will hopefully encourage people to develop this course further. Boud 09:26, 29 June 2011 (UTC)Reply



The course has again been used from Feb to June 2012 and the exercises are now available in WIMS - see the Exercises section in the article. A few minor errors were corrected in the Wikimedia Commons sources and rendered versions of the pdf files. This year's students again found the difficulty level about right - not too easy, not too difficult. Diagrams and some algebraic calculations in the WIMS exercises would be a good next step for the 2013 version. Boud (talk) 09:04, 28 June 2012 (UTC)Reply

pdf uploading - discussion and notes


See commons:Commons_talk:File_types and find the section What_is_a_reasonable_way_to_upload_a_wikiversity_pdf_fullscreen_presentation + source?. It may have been archived by the time you read this - look for a link to the archives near the top of the page. Boud 10:55, 6 July 2011 (UTC)Reply

.fig files

  • xfig -specialtext -latexfonts -startlatexFont default FILENAME.fig for using latex type fonts for formulae
  • export to .svg format
  • aptitude install librsvg2-bin (debian) for a lightweight svg viewer
  • let's try rotation1 and rotation2:
      Euclidean rotation first step

Boud 11:47, 6 July 2011 (UTC)Reply

The .svg exported files do not use the LaTeX special information for writing mathematical expressions. TODO: It would be great if someone found a tool for creating .svg files as good as .eps files that are made using the "combined ps/latex" pstex + pstex_t output files from xfig. But postscript to pdf works at the present, so should be OK for the first iteration, prior to an svg vs LaTeX tech debate.

My .fig files for the SR part of the course are now all uploaded, i think. The script for downloading them from Commons and generating .eps files seems to work. It just needs adding a download of svg/png files and converting them to .eps and we are fairly close to being able to upload the sr.pdf along with the full source code, making something like 1/4 of the course nearly being ready. Boud 23:33, 8 July 2011 (UTC)Reply

Feasibility of videos


I'm thinking of recording videos to go along with the pdfs + exercises. Commons:Commons:Video recommends VP9/webm videos, but the VP9 patent issue looks a bit fuzzy. w:Theora in w:ogv containers is accepted, and would be appear to be the more ethical choice, so that would be preferable, e.g. container:ogv, video codec:theora, audio codec:vorbis (see allowable file types).

If you're interested in participating in live recordings, then please add a comment with your signature ~~~~. A possible first session would be March 2024 - the bbb location will be provided later.

Conditions of participating in the live recording
  • your voice will be included in the recording if you ask questions interactively during the session and will be included in the video published on Wikimedia Commons under CC BY-SA
  • the chatbox and participant list will not be included in the video (you are welcome to use the chatbox, in which case I'll react to questions without naming you)
  • please don't enable your camera during the recording, since the aim is to mainly show slides, possibly also diagrams scribbled on the whiteboard, with a small box to show the lecturer's (my) face to make it a bit more friendly
  • if you draw on the whiteboard during the recording, then your username is likely to be recorded in the video to be published on Wikimedia Commons.

Boud (discusscontribs) 16:58, 5 March 2023 (UTC)Reply



I haven't done this before, so I don't yet know how much post-recording editing will be needed - e.g. if I say something wrong, misleading, confusing or inaudible, should I cut and paste that bit of the video? Redoing a 90-minute or so video just for a single wrong sentence would be a lot of work, but leaving up a video with confusing, misleading or wrong statements would be annoying to people trying to learn. I guess an alternative to directly editing the video would be to put comments on the Commons page of the video, e.g. "my statement at 14:20-15:50 was wrong because ..." - and then let the WMF community decide how to handle that - e.g. adding a subtitle file with corrections would be a lightweight (cpu, disk space) way of adding corrections that I could trivially do myself. This is not a multi-million dollar Bollywood or Hollywood production :).

Suggestions welcome. Boud (discusscontribs) 17:19, 5 March 2023 (UTC)Reply

Mpv with e.g. mpv --start=00:00 --end=14:20 file.mpv --start=15:50 file.mpv -o out.mpv or something similar should be straightforward for cutting out pieces if necessary. Boud (discusscontribs) 22:06, 12 January 2024 (UTC)Reply

Likely participants


I don't expect many :), but who knows? Please list your possible time slots - which would be on XXX DD March HH:MM-HH:MM UTC+1 ... (TBC). See w:timezone if you're not sure of your timezone. Boud (discusscontribs) 17:31, 5 March 2023 (UTC)Reply

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