Wikipedia:Reference desk/Archives/Science/2019 July 9

= July 9 =

Shear force v Reaction (physics)

 * Are shear force and Reaction force the same thing??
 * Is hydrostatic pressure a term used to describe the tension force in the water? Do we use hydrostatic pressure when we talk about the tension force of water?

--Exert yourself (talk) 13:29, 9 July 2019 (UTC)


 * !) No. The reaction to a shear force would be a deformation or fracture.


 * 2) Tension ? No. More like compression force. If you are talking about surface tension, that's unrelated. SinisterLefty (talk) 13:49, 9 July 2019 (UTC)


 * Oh! Thank you so much! I feel I can better distinguish between those. --Exert yourself (talk) 03:33, 10 July 2019 (UTC)

Octonion basis vectors
First, I am relatively new to contributing to wikipedia; so I am not sure if I a going about this correctly, or in the correct location to post.

I was reading the page on Octonions, trying to understand some basics before I take on introdution academic texts. In the definition section it made reference to "non-scalar basis elements". I was not familiar with the phrase or the intent, so I did a google search and found about 50 instances of the phrase. None were clear as to meaning, generally they were used in advanced technical papers on various mathematical topics besides octonions. I then came up with zero hits when combined with "definition". I spent about four hours chasing this.

Going outside wikipedia searching on octonions, I realized the concept being described was just the set of basis unit vectors without the scalar unit vector value "e0" a/k/a/ "1". Just for clarification, I should note that each unit basis vector can be multiplied by a scalar value; so when working with an octonion one has nine numbers that qualify as "scalar".

For clarification I edited the octonion page by adding {{e_{1},e_{2},e_{3},e_{4},e_{5},e_{6},e_{7}}.

The phrase "non-scalar basis elements" is correct, just a little knotty for a newbie. It would also be correct to say "the set of unit basis elements when squared equal negative one".

I just got a message on my watch list saying what I had done was rejected because it was "not constructive", and that I should use sandbox. What I have done is parsimonious and most explicit, and nothing else one could write could be more explicit in describing the matter at hand.

If written explicitly, it would have saved me or someone else, from the loss of time. I am not seeking to have the description "non-scalar basis elements" removed, or adding another knotty explanation included.

Not being an expert on the subject, a newbie must check, double check, and keep checking until competent to prove the concept. In hindsight I would have preferred to have flagged the phrase explaining the confusion, and let someone else improve it.

Not sure how to proceed, or if I should ignore and let it go.

'MatthewDougherty (talk) 19:41, 9 July 2019 (UTC)'


 * Your edit to octonion still stands (at present), and has not been reverted as "not constructive". The same appears to be true for all your other edits.  Perhaps you saw the "not constructive" message on a page history, or on another users contributions list, and mistakenly took it as applying to yourself.  So thank you for you contributions and please be bold and continue to edit. catslash (talk) 23:36, 9 July 2019 (UTC)

Must have been a timing issue. I originally saw "not constructive", but when writing this post I went back to the rejection to copy something, and found the rejection missing. Not understanding the mechanics of wikipedia editing, I completed my post and pushed the publish changes on this talk page. Since then, I found the talk section on Octonions, so in future I will restrict these topic specific questions to those talk pages. thx, will keep trying. 'MatthewDougherty (talk) 23:59, 9 July 2019 (UTC)'


 * Yes, Talk:Octonion is the right place to raise any issues regarding the octonian page - and as there are 111 people watching the page, you are likely to get a response. For pages with fewer watchers, it may be necessary to bring the issue here to get any attention - though this is not the intended function of the reference desk pages. catslash (talk) 00:29, 10 July 2019 (UTC)