Talk:Wave packet

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Contents 1 Wave packet image 2 Complete Rubbish Without Math 3 Wavepackets and metaphysics 4 Mathematics Section

[edit] Wave packet image

To those who felt the wavepacket representation image was confusing. I believe it is useful to have a graphical representation of a wave packet on this page. Any suggestions on how to improve the image to your tastes? Note that the "axis labels" of a wave packet are completely arbitrary. It depends on the representation one is working in, the point is the shape of the graph not the labels.

For now I'm restoring the image, so the site will be more clear. Let me know how to improve it, or upload a better one rather than just deleting content.

My main objection to the image is the totally ambiguous arrows. If the horizontal axes is position, then I would gather that the Position arrow is indicating the line (whereas its not clearly pointing to it), and then the momentum arrow is trying to indicate that the momentum is related to the width of the wave packet. The caption still does nothing for me, because it does not explain what the arrows are indicating, or that we are in position-space. I'll add to the caption, but it would be ever so much more clear if the image itself was made more clear. Laura Scudder 20:30, 17 Mar 2005 (UTC)

If you read the text the ambiguity in the position is supposed to demonstrate the uncertainty principle. What I was trying to illustrate is that the "position" is somewhat fuzzy, I'm not sure how else to draw it. I suppose I could remove the arrows? Not sure that this would be more effective though. Some sort of gaussian distribution overlay may work better? I'll have to explore some possibilities. John187 16:33, 18 Mar 2005 (UTC)

I understand the idea of not labelling the graph, since a wave packet looks identical in position-space and momentum-space... however, having a graph without any label on the x- and y-axis is really bad form. It's confusing to specialists and non-specialists alike, since it doesn't really represent anything (are you plotting amplitude vs. time (amplitude of what?), or time vs. distance, or length vs. mass ... or what?). Why not just have two pictures: one for position-space, one for momentum-space, and let the reader see how similar they look. And you don't need to label "position" if the x-axis is already "position"... it should be clear to the reader that the position is ill-defined, since a range of positions is included in the packet. --132.206.205.100 14:07, 15 Jun 2005 (UTC)

Simply removing the arrows would be worse without axes labels. Then it's just a meaningless graph. The optimum would be axes labels and, as suggested, plots in both position and momentum space to convey the relationship. And if there must be arrows in addition to axes labels, I think instead of momentum and position, it'd be preferable to be clearer and choose for instance δp, δx. I would just do this myself, but I currently lack ability to generate acceptable quality pngs. --Laura Scudder | Talk 16:19, 15 Jun 2005 (UTC)

This discussion of wave packets seems almost completely based on their interpretation in quantum mechanics, and contains little discussion of generic properties of wave packets. The simplest example that I can think of is the complete lack of information on the group velocity, a concept that is both a general property of a wave packet and is a part of nearly every subject that works with waves and wave packets. The current organizational structure makes it difficult to include such information.

[edit] Complete Rubbish Without Math

If this article doesn't include math, or links to a more mathematical article then it is complete rubbish. Metaphysics should be in a wholly separate article and not included in wave packets. These are not only quantum phenomena, they are mathematical outcomes of waves. Please for the sake of wikipedia clean this article up. I don't want to insult the gracious individuals who have made this article but it is incomplete and misleading. More math please, less junk philosophy!

Wikipedia is produced by volunteers, and I personally don't understand the math you describe. Are you volunteering to provide the improvement you describe? If so, let's see what you had in mind. If not, do you really think your attitude is what will get people to happily pitch in and fix it? Art LaPella 01:33, 14 November 2005 (UTC)

[edit] Wavepackets and metaphysics

It seems rather odd that an article on wavepackets is about 50% on metaphysics...the article itself reads almost like an opinion piece. I'm going to put an NPOV tag on it; this page also needs some cleanup I think. --HappyCamper 12:39, 12 January 2006 (UTC)

I don't understand the science very well and you may be right about too much metaphysics, but I do have an opinion on unexplained tags. What opinion is over-represented or under-represented? I didn't notice any typical cleanup problems like spelling or grammar. Art LaPella 21:42, 12 January 2006 (UTC)

For example, for me, the first sentence is far too loaded: "The wave packet is one of the most widely misunderstood and misused concepts in physics." Also, at minimum, it should mention some of the influences that de Broglie had on this concept. This name is currently absent from the article!

Well, I suppose it would be unfair of me to add those tags, but for some of the articles that I found, I added these two, and after 9 months everything was fixed up. You can remove them if you like, as I probably won't get a chance to add more mathematical detail to this anytime soon. :-) --HappyCamper 22:04, 12 January 2006 (UTC)

Better. Art LaPella 02:13, 13 January 2006 (UTC)

As far as I'm concerned the metaphysics section could be cut back. I haven't done it myself yet because I'm scared of only leaving some disconnected nonsense and making the situation worse. — Laura Scudder ☎ 23:55, 17 February 2006 (UTC)

I have to say, I'd rather not see any reference to metaphysical concepts on this page. Consider it a personal bias if you will, but I think a subject that is fundamentally scientific in nature is serriously comprimised when metaphysics are included. I propose a rewrite, of a few of the paragraphs at least, it tends to read like a 10th grade science essay rather than an encyclopedia article. For instance, the first sentence should be eliminated altogether, it does't really add anything but ambiguity to the article. But thats just my $0.02. Davepetr 20:11, 17 February 2006 (UTC)

10th grade may be aiming a bit high... if it's possible to write an article in a simpler form that's equally accurate, let it be so. As far as the metaphysics section goes - a lot of that is just really bad logic, and I'm going to weed some of it now. Pjrich 06:10, 1 March 2006 (UTC)

[edit] Mathematics Section

I am starting to put in a mathematics sections and some relevent diagrams. It is going to take place over the next couple of weeks. If able, feel free to make corrections or additions. --Nkrupans 06:13, 20 January 2006 (UTC)

Sorry for editing the front page. My comment should be placed here:

Let me add a little comment without which above-mentioned derivation would be hard to comprehend by most people myself included. Not everybody has simply patience to solve puzzles each time he or she tries to learn anything about quantum mechanics. This differential equation has a simple and useful solution in the form of something close to Maxwell distribution:

where Ao and ko are constants.

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