Talk:Lamb waves

message: It says "in-plane and out-of-plane components".  I don't understand this.  What plane is meant?  Since the motion is all in the x and z directions, never in the y direction, then the motion of each particle must be within a plane.  Possibly in-plane means in the x direction only (not z), because it's within a plane parallel to the sides of the plate.  If so, this needs to be explained to the reader.  --Coppertwig (talk) 17:30, 30 December 2007 (UTC)
replies: text: It means the plane of the plate. I'll clean up the text to clarify this. Adrian Pollock (talk) 19:03, 30 December 2007 (UTC)
thread_title:  What does "out-of-plane" mean? 

message: I hope you don't mind.  I deleted the Overview section heading, and I'm thinking of editing to somehow end up with a lead section of 2 to 4 paragraphs.  It's my understanding of the Wikipedia Manual of Style that there isn't supposed to be a section with a title like "overview";  the introduction or lead is supposed to have no heading, and that the other sections are supposed to have more specific headings.  --Coppertwig (talk) 17:15, 12 January 2008 (UTC)
replies: text: Go for it !  I wasn't aware of these points of Wikipedia style when I started this article. The intent of the other named sections, once I had started working on them, was to expand on the content of the overview while maintaining a decently balanced coverage overall.  You may be able to get the article into the desired style by making a short introduction and then checking the left-over material from the previous overview, to see whether any of it would be useful for introducing/starting the named sections. As first written, the named sections were intended to be based on information conveyed in the overview, so after deletion of the original overview they will need to be reviewed / edited for approachability. Thanks, Adrian Pollock (talk) 01:09, 15 January 2008 (UTC)
replies: text: Right.  Thanks. I might do this though not right now. --Coppertwig (talk) 03:24, 15 January 2008 (UTC)
replies: text: Ah, I was misreading you.  You only deleted the heading, in my paranoia I thought you had deleted the whole section. I only just now went to actually look. OK, what we are left with is simply an introductory section that is too long. So in the first approximation, what we need is simply a cut-paste-and-polish kind of operation one subtopic at a time - shouldn't be hard.  Adrian Pollock (talk) 05:52, 15 January 2008 (UTC)
thread_title:  Lead section 

message: :
\frac{\tan(\beta d / 2)} {\tan(\alpha d / 2)} = - \frac
{4 \alpha \beta k^2}
{(k^2 - \beta^2)^2}
OK, there's equation 1a from the page by Zhenqing.  Are you sure these equations make sense??  The left-hand-sides of the two equations are identical to each other. If it makes sense to you, you can put this into the article and also I'm sure you can figure out how to express the other equation in LaTeX too. --Coppertwig (talk) 21:03, 26 January 2008 (UTC)
replies: text: Yes, these equations do make sense and I will look forward to handling the second one.  The reason there are two of them is that the first describes the symmetrical modes and the second describes the antisymmetric modes. The definitions of alpha and beta (etc.?) in Zhenqing's article have to be written into our text also; these bring in the angular frequency omega, which is how the characteristics equations permit computation of frequency as a function of wave number, hence of the phase and group velocities.  Question: as a matter of Wikipedia style as well as feasibility, do you think the expressions for alpha, beta (?etc.) should be in full LaTeX with its big script, or is it acceptable to write them in some smaller format - after all, they are only definitions supporting the main equations ? Thanks, Adrian Pollock (talk) 22:23, 26 January 2008 (UTC)

text: \alpha^2 = \frac{\omega^2}{c_l^2} - k^2,
\quad \quad \beta^2 = \frac{\omega^2}{c_t^2} - k^2, 
and k = ω/Cp, where k is the ...
I inserted an extra word "where" before the last k because otherwise the k looks like part of the previous equation.  (alternatively, delete "and" and insert another "and" where I put "where" :-) I found out how to spread equations out on a line. "\quad" adds whitespace within math mode -- just like in TeX.  Reading the instruction pages can do wonders. I also just added a backslash before "tan" in the above equations -- I suppose it looks a little better or is more correct that way.
Actually, if you want opinions about what is the correct way to typeset math, Michael Hardy may be a good person to ask.  (But read Help:math and Wikipedia:Manual of Style (mathematics) before asking him -- you might find answers there.)
Please check over the equations and make sure they're the same as on the original web page.  I found some of the characters hard to see.  And OK, if it's for two different modes, I guess the equations can be different -- but shouldn't some of the variables be marked with different subscripts or something then?  Oh, well, maybe that would complicate things too much. I guess it's OK. --Coppertwig (talk) 00:03, 27 January 2008 (UTC)

text: I'm hoping to find the proper equations in a few days to put up instead of these, so I'm not putting more time into these at this point. Adrian Pollock (talk) 19:39, 27 January 2008 (UTC)
thread_title:  Equations 

message: I got my degree in physics, but I can barely understand what it's all about.  It's way too abstract.  There isn't a concrete sentence in the whole article.  I looked Lamb Waves up because somebody mentioned it in the comment section in an article about the Tonga Volcano.  The words 'volcano', 'tsunami', 'earth', 'land', 'shock' or any kind of musical reference never appear, although I'm sure they're related.  'vibration' only appears in a reference.   
If I drop a large crescent wrench onto a wooden floor, there's going to be Lamb waves along the surface of the floor?  I'm not talking about "a hard object on a flat, elastic surface", I'm talking about something concrete.  Here's how to tell: if a word isn't Animal, Vegetable or Mineral, it isn't concrete.  You can visualize a crescent wrench on a wooden floor.  To visualize a hard object on a flat, elastic surface, you have to dream up what kind of object and what kind of floor, and visualize them.  Don't start with abstractions, start with concrete things the reader can relate to.
Take the recent (Jan 2022) volcanic eruption on Tonga.  This generated Lamb waves in the surface of the earth?  Describe it, and show how the equations apply to that situation.  Maybe musical instruments have Lamb waves?  Which ones? Describe that, too.  There's lots of things that trigger Lamb waves: you should talk about some of them, too.
That first sentence doesn't do anything  to explain to the reader what they're about to get into.  It would make a good second paragraph.  Start with something like "Lamb waves are a particular kind of vibration on a surface.  Earthquakes blah blah Lamb waves.  A trombone being played blah blah Lamb waves.  Waves on the surface of water aren't Lamb waves because blah blah blah.  
OsamaBinLogin (talk) 01:55, 25 September 2022 (UTC)
thread_title:  Examples