Talk:Michelson–Morley experiment/GA1

Latest comment: 12 years ago by Stigmatella aurantiaca in topic GA Review

GA Review

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Reviewer: Wer900 (talk · contribs) 01:34, 24 May 2012 (UTC)Reply

Basic criteria check

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The article obviously failed on all counts. Here's my assessment of how the article meets the basic GA criteria...

Basic Ratings
Category Rating
MoS  
NPOV  
Accuracy  
Broad  
Stable  
Prose  

Prose

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The prose is what I am having the greatest problem with, as evidenced by my negative review of it. In many places, the prose is quite choppy, with extremely short, one-line sentences (on my 13-inch-screen laptop) in one paragraph and three-lined sentences in the next. In addition, functional elements which are not ideal are used, such as the en-dash or even the hyphen. In yet other examples, unnatural explanations are used (involving parenthetical expressions like this one) where natural explanations could be used. Example (from oldid 491686307), bold indicates problems:

Starting in 1885, Michelson collaborated with Edward Morley, spending considerable time and money to repeat the Fizeau experiment on Fresnel's drag coefficient (finished in 1886)',[1] and to repeat the Michelson experiment (finished in 1887).[2]

At this time Michelson was professor of physics at the Case School of Applied Science, and Morley was professor of chemistry at Western Reserve University, which shared a campus with the Case School on the eastern edge of Cleveland.(transition sentence necessary) Michelson suffered a nervous breakdown in September 1885, from which he recovered in October 1885. Morley ascribed this breakdown to the intense work of Michelson during the preparation of the experiments. In 1886, Michelson and Morley successfully confirmed Fresnel's drag coefficient - (better functional element than "-" necessary) this result was also considered as a confirmation of the stationary aether concept.



This strengthened the hope of finding the aether wind. (abnormally short) Thus, (comma added) Michelson and Morley created an improved version of the Michelson experiment with more than enough accuracy to detect this hypothetical effect. The experiment was performed in several periods of concentrated observations (what are "concentrated observations?") between April and July 1887, in Adelbert Dormitory of WRU (later renamed Pierce Hall, demolished in 1962).[A 1][A 2]

As shown in Fig. 4, the light was repeatedly reflected back and forth along the arms of the interferometer, increasing the path length to 11 m. At this length, the drift would be about 0.4 fringes. To make that easily detectable, the apparatus was assembled in a closed room in the basement of the heavy stone dormitory, eliminating most thermal and vibrational effects. Vibrations were further reduced by building the apparatus on top of a large block of sandstone (Fig. 1), about a foot thick and five feet square (5 square feet?), which was then floated in an annular trough of mercury. They calculated that effects (please restate what these "effects" are) of about 1/100th of a fringe would be detectable.

 
Figure 5. Fringe pattern produced with a Michelson interferometer using white light. As configured here, the central fringe is white rather than black.

Michelson and Morley, (comma added) and other early experimentalists using interferometric techniques in an attempt to measure the properties of the luminiferous aether, used monochromatic light only for initially setting up their equipment, always switching to white light for the actual measurements. The reason is that measurements were recorded visually. Monochromatic light would result in a uniform fringe pattern. Lacking modern means of environmental temperature control, the fringes showed continual drift even though the interferometer might be set up in a basement. Since the fringes would occasionally disappear due to vibrations by passing horse traffic, distant thunderstorms and the like, it would be easy to "get lost" when the fringes returned to visibility. The advantages of white light, which produced a distinctive colored fringe pattern, far outweighed the difficulties of aligning the apparatus due to its low coherence length. As Dayton Miller wrote, "White light fringes were chosen for the observations because they consist of a small group of fringes having a central, sharply defined black fringe which forms a permanent zero reference mark for all readings."[A 3][B 1] (this paragraph is in the wrong place)

The mercury pool allowed the device to be easily turned, so that given a single steady push it would slowly rotate through the entire range of possible angles to the "aether wind", while measurements were continuously observed by looking through the eyepiece. Even over a period of minutes, it was presumed that some sort of effect would be noticed, since one of the arms would inevitably turn into the direction of the wind and the other away.

It was expected that the effect would be graphable as a sine wave with two peaks and two troughs per rotation of the device. This is because during each full rotation, each arm would be parallel to the wind twice (facing into and away from the wind giving identical readings) and perpendicular to the wind twice. Additionally, due to the Earth's rotation, the (aether) wind would be expected to show periodic changes in direction and magnitude during the course of a sidereal day.

These prose issues are representative of what is wrong with the entire article - erratic sentence structure and poor word choice. For example, the lead says that the experiment was "aimed at..." While this is technically correct, the experiment sounds more like a catapult than the Michelson-Morley experiment with such phrasing. This, in addition to "measurements were observed." Measurements are made, not observed.

I would not let this good article nomination pass now, it has far too many issues. However, I am a new user - anyone else can pass it at any time if they have not contributed substantially to it and are more experienced than I am in making such judgement calls. Additionally, the article appears to be rated as a "C"-class by multiple WikiProjects, further corroborating my conclusion. Wer900 talkessay on the definition of consensus 01:56, 24 May 2012 (UTC)Reply

The physics and relativity project ratings date from 2008 and 2009, respectively. D.H, the main science contributor to this article over the last two years and an accomplished physicist with multiple publications, is not a native English-speaker. My role in the last few months has mostly been to rework his text without removing all of the unique flavor of his language. Apparently you would wish that I had homogenized his text into completely standard English. I have far too much respect for D.H to have wished to do that. Stigmatella aurantiaca (talk) 10:22, 24 May 2012 (UTC)Reply
Improvements of the prose are of course welcome, so don't hesitate to make changes. --D.H (talk) 10:58, 24 May 2012 (UTC)Reply
Please do not get excessively judgemental. I had no knowledge of your intentions.Wer900 talkessay on the definition of consensus 23:06, 24 May 2012 (UTC)Reply
I can indeed be judgmental of somebody who is so careless that he does not check the date of project ratings, or who spells "judgmental" "judgemental" the way that you just did. The page ratings were automatically reset to zero around the end of last month because of our extensive edits. From that fresh start, they have been mostly 4s and 5s. I have reason to believe that these multiple votes reflect the quality of our work better than your one single vote. Stigmatella aurantiaca (talk) 23:27, 24 May 2012 (UTC)Reply
  1. ^ Cite error: The named reference michel1a was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference michel2 was invoked but never defined (see the help page).


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Cite error: There are <ref group=B> tags on this page, but the references will not show without a {{reflist|group=B}} template (see the help page).