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		<title>en&gt;Mild Bill Hiccup: Cleaned up using AutoEd</title>
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		<summary type="html">&lt;p&gt;Cleaned up using &lt;a href=&quot;/index.php?title=WP:AutoEd&amp;amp;action=edit&amp;amp;redlink=1&quot; class=&quot;new&quot; title=&quot;WP:AutoEd (page does not exist)&quot;&gt;AutoEd&lt;/a&gt;&lt;/p&gt;
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		<title>en&gt;ChrisGualtieri: Remove stub tag(s). Page is start class or higher + General Fixes + Checkwiki fixes using AWB</title>
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		<summary type="html">&lt;p&gt;Remove stub tag(s). Page is start class or higher + General Fixes + Checkwiki fixes using &lt;a href=&quot;/index.php?title=Testwiki:AWB&amp;amp;action=edit&amp;amp;redlink=1&quot; class=&quot;new&quot; title=&quot;Testwiki:AWB (page does not exist)&quot;&gt;AWB&lt;/a&gt;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;{{For|other persons of the same name|Alexander Macfarlane (disambiguation)}}&lt;br /&gt;
{{Infobox scientist&lt;br /&gt;
|name              = Alexander Macfarlane&lt;br /&gt;
|image             = Macfarlane_Alexander_math.jpg&lt;br /&gt;
|image_size       = 300px&lt;br /&gt;
|caption           = Alexander Macfarlane (1851&amp;amp;nbsp;— 1913)&lt;br /&gt;
|birth_date        = {{birth-date| April 21, 1851}}&lt;br /&gt;
|birth_place       = [[Blairgowrie and Rattray|Blairgowrie]], [[Scotland]]&lt;br /&gt;
|death_date        = {{death-date|August 28, 1913 }}&lt;br /&gt;
|death_place       = [[Chatham, Ontario]], [[Canada]]&lt;br /&gt;
|residence         = Chatham, Ontario&lt;br /&gt;
|citizenship       =&lt;br /&gt;
|nationality       = [[Scotland|Scottish]]&lt;br /&gt;
|ethnicity         =&lt;br /&gt;
|field             = [[Logic]]&amp;lt;br&amp;gt;[[Physics]]&amp;lt;br&amp;gt;[[Mathematics]]&lt;br /&gt;
|work_institutions = [[University of Texas]]&amp;lt;br&amp;gt;[[Lehigh University]]&lt;br /&gt;
|alma_mater        = [[University of Edinburgh]]&lt;br /&gt;
|doctoral_advisor  = [[Peter Guthrie Tait]]&lt;br /&gt;
|doctoral_students =&lt;br /&gt;
|known_for         = Scientific biographies&amp;lt;br&amp;gt;Algebra of Physics&lt;br /&gt;
|author_abbrev_bot =&lt;br /&gt;
|author_abbrev_zoo =&lt;br /&gt;
|influences        = [[William Rowan Hamilton]]&amp;lt;br&amp;gt;[[William Kingdon Clifford]]&amp;lt;br&amp;gt;[[Arthur Cayley]]&lt;br /&gt;
|influenced        = [[G. W. Pierce]]&amp;lt;br&amp;gt;[[Quaternion Society]]&lt;br /&gt;
|prizes            =&lt;br /&gt;
|religion          =&lt;br /&gt;
|footnotes         =&lt;br /&gt;
|signature         =&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
&amp;#039;&amp;#039;&amp;#039;Alexander Macfarlane&amp;#039;&amp;#039;&amp;#039; [[Fellow of the Royal Society of Edinburgh|FRSE]] (April 21, 1851&amp;amp;nbsp;– August 28, 1913) was a [[Scotland|Scottish]] [[logic]]ian, [[physicist]], and [[mathematician]].&lt;br /&gt;
&lt;br /&gt;
Macfarlane was born in [[Blairgowrie and Rattray|Blairgowrie]], [[Scotland]] and studied at the [[University of Edinburgh]].  His [[doctoral thesis]], on the conditions governing the [[electric spark]], was subsequently published in the &amp;#039;&amp;#039;[[Transactions of the Royal Society of Edinburgh]]&amp;#039;&amp;#039;. It brought him to the notice of [[James Clerk Maxwell]], and in 1878 Macfarlane was elected a [[Fellow of the Royal Society of Edinburgh]]&lt;br /&gt;
&lt;br /&gt;
During his life, Macfarlane played a prominent role in research and education. He taught at the universities of Edinburgh and [[University of St Andrews|St Andrews]], was physics [[professor]] at the [[University of Texas at Austin|University of Texas]] (1885&amp;amp;nbsp;– 1894),&amp;lt;ref&amp;gt;See the [http://www.lib.utexas.edu/taro/utcah/00515/cah-00515.html Macfarlane papers at the University of Texas].&amp;lt;/ref&amp;gt; professor of Advanced Electricity, and later of [[mathematical physics]], at [[Lehigh University]]. MacFarlane was the secretary of the [[Quaternion Society]] and compiler of its publications.&lt;br /&gt;
&lt;br /&gt;
Macfarlane was also the author of a popular 1916 collection of mathematical biographies (&amp;#039;&amp;#039;Ten British Mathematicians&amp;#039;&amp;#039;), a similar work on physicists (&amp;#039;&amp;#039;Lectures on Ten British Physicists of the Nineteenth Century&amp;#039;&amp;#039;, 1919), and he compiled a [[bibliography]] on [[quaternion]]s in 1904.&lt;br /&gt;
Macfarlane was caught up in the revolution in [[geometry]] during his lifetime,&amp;lt;ref&amp;gt;&amp;#039;&amp;#039;1830–1930: A Century of Geometry&amp;#039;&amp;#039;, L Boi, D. Flament, JM Salanskis editors, Lecture Notes in Physics #402, Springer-Verlag ISBN 3-540-55408-4&amp;lt;/ref&amp;gt; in particular through the influence of [[G. B. Halsted]] who was mathematics professor at the University of Texas. Macfarlane originated an &amp;#039;&amp;#039;Algebra of Physics&amp;#039;&amp;#039;, which was his adaptation of quaternions to physical science. His first publication on &amp;#039;&amp;#039;Space Analysis&amp;#039;&amp;#039; preceded the presentation of [[Minkowski Space]] by seventeen years.&amp;lt;ref&amp;gt;A. Macfarlane (1891) &amp;quot;Principles of the Algebra of Physics&amp;quot;, &amp;#039;&amp;#039;Proceedings of the [[American Association for the Advancement of Science]]&amp;#039;&amp;#039; 40:65-117. It was 1908 when [[Hermann Minkowski]] proposed his spacetime.&amp;lt;/ref&amp;gt;&lt;br /&gt;
&lt;br /&gt;
Macfarlane actively participated in several [[International Congress of Mathematicians|International Congresses of Mathematicians]] including the primordial meeting in Chicago, 1893, and the Paris meeting of 1900 where he spoke on &amp;quot;Application of space analysis to curvilinear coordinates&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
Macfarlane retired to [[Chatham, Ontario]], where he died in 1913.&lt;br /&gt;
&lt;br /&gt;
==Space analysis==&lt;br /&gt;
Alexander Macfarlane stylized his work as &amp;quot;Space Analysis&amp;quot;. In 1894 he published his five earlier papers and a book review of [[Alexander MacAulay]]’s &amp;#039;&amp;#039;Utility of Quaternions in Physics&amp;#039;&amp;#039;. This collection is now available on-line.&amp;lt;ref&amp;gt;A. Macfarlane (1894) &amp;#039;&amp;#039;[http://www.archive.org/details/principlesalgeb01macfgoog Papers on Space Analysis]&amp;#039;&amp;#039;, B. Westerman, New York, weblink from [[archive.org]]&amp;lt;/ref&amp;gt;&lt;br /&gt;
Page numbers are carried from previous publications, and the reader is presumed familiar with quaternions. The first paper is &amp;quot;Principles of the Algebra of Physics&amp;quot; where he first proposes the [[hyperbolic quaternion]] algebra, since &amp;quot;a student of physics finds a difficulty in principle of quaternions which makes the square of a vector negative.&amp;quot; The second paper is &amp;quot;The Imaginary of the Algebra&amp;quot;. Here he introduces the [[versor#Hyperbolic versor|hyperbolic versor]] as the hyperbolic quaternion corresponding to the [[versor]] of Hamilton. The presentation is encumbered by the notation&lt;br /&gt;
:&amp;lt;math&amp;gt;h \alpha ^ A = \cosh A + \sinh A \ \alpha ^{\pi/2}.&amp;lt;/math&amp;gt;&lt;br /&gt;
Later he conformed to the notation exp(A α) used by Euler and Sophus Lie. The expression &amp;lt;math&amp;gt;\alpha ^{\pi/2}&amp;lt;/math&amp;gt; is meant to emphasize that α is a &amp;#039;&amp;#039;right versor&amp;#039;&amp;#039;, where π/2 is the measure of a [[right angle]] in [[radian]]s. The π/2 in the exponent is, in fact, superfluous.&lt;br /&gt;
&lt;br /&gt;
Papers three and four are &amp;quot;Fundamental Theorems of Analysis Generalized for Space&amp;quot; and &amp;quot;On the definition of the Trigonometric Functions&amp;quot;, which he had presented the previous year in Chicago at the &amp;#039;&amp;#039;Congress of Mathematicians&amp;#039;&amp;#039; held in connection with the [[World&amp;#039;s Columbian Exhibition]]. He follows [[George Salmon]] in exhibiting the [[hyperbolic angle]], argument of [[hyperbolic function]]s. The fifth paper is &amp;quot;Elliptic and Hyperbolic Analysis&amp;quot; which considers the [[spherical law of cosines]] as the fundamental theorem of the [[sphere]], and proceeds to analogues for the ellipsoid of revolution, general [[ellipsoid]], and equilateral [[hyperboloid]]s of one and two sheets, where he provides the [[hyperbolic law of cosines]].&lt;br /&gt;
&lt;br /&gt;
In 1900 Alexander published &amp;quot;Hyperbolic Quaternions&amp;quot;&amp;lt;ref&amp;gt;Macfarlane (1900) &amp;quot;Hyperbolic Quaternions&amp;quot; &amp;#039;&amp;#039;Proceedings of the Royal Society at Edinburgh&amp;#039;&amp;#039;, 1899-1900 session, pp. 169–181&amp;lt;/ref&amp;gt; with the Royal Society in Edinburgh, and included a sheet of nine figures, two of which display conjugate [[hyperbola]]s. Having been stung in the &amp;#039;&amp;#039;Great Vector Debate&amp;#039;&amp;#039; over the non-associativity of his Algebra of Physics, he restored associativity by reverting to  [[biquaternion]]s, an algebra used by students of Hamilton since 1853.&lt;br /&gt;
&lt;br /&gt;
==Works==&lt;br /&gt;
* {{cite book | last = Macfarlane | first = Alexander | title = Lectures on Ten British Mathematicians of the Nineteenth Century | publisher = John Wiley and Sons | location = New York | year = 1916 | url = http://ebooks.library.cornell.edu/cgi/t/text/text-idx?c=math;cc=math;view=toc;subview=short;idno=05070001}}&amp;lt;ref&amp;gt;{{cite journal|author=Mason, Thomas E.|title=Review: Alexander Macfarlane, &amp;#039;&amp;#039;Ten British Mathematicians&amp;#039;&amp;#039;|journal=Bull. Amer. Math. Soc.|year=1917|volume=23|issue=4|pages=191–192|url=http://www.ams.org/journals/bull/1917-23-04/S0002-9904-1917-02913-8/}}&amp;lt;/ref&amp;gt;&lt;br /&gt;
* {{cite book | last = Macfarlane | first = Alexander | title = Lectures on Ten British Physicists of the Nineteenth Century | publisher = John Wiley and Sons | location = New York | year = 1919 | url = http://www.archive.org/details/lecturesontenbri00macfrich}}&lt;br /&gt;
* {{gutenberg author|id=Alexander_MacFarlane|name=Alexander Macfarlane}}&lt;br /&gt;
&lt;br /&gt;
==Notes and references==&lt;br /&gt;
{{reflist}}&lt;br /&gt;
&lt;br /&gt;
* {{cite journal | author = Colaw, J. M. | title = Alexander Macfarlane, M.A., D. Sc., LL.D | journal = The American Mathematical Monthly | year = 1895 | volume = 2 | pages = 1–4 | doi = 10.2307/2971573 }}&lt;br /&gt;
* Robert de Boer (2009) [http://www.webcitation.org/5kmWeo7j0 Biography of Alexander Macfarlane] from [[WebCite]].&lt;br /&gt;
* [http://www.electricscotland.com/history/canada/kent/macfarlane_alexander.htm Electric Scotland historical biography]&lt;br /&gt;
* [[Cargill Gilston Knott|Knott, Cargill Gilston]], &amp;#039;&amp;#039;Alexander Macfarlane&amp;#039;&amp;#039; (obituary), [[Nature (journal)|Nature]], 25 September 1913.&lt;br /&gt;
* [http://www.lib.utexas.edu/taro/utcah/00515/cah-00515.html Macfarlane papers at the University of Texas]&lt;br /&gt;
&lt;br /&gt;
{{Authority control|VIAF=50005071}}&lt;br /&gt;
&lt;br /&gt;
{{Persondata &amp;lt;!-- Metadata: see [[Wikipedia:Persondata]]. --&amp;gt;&lt;br /&gt;
| NAME              = Macfarlane, Alexander&lt;br /&gt;
| ALTERNATIVE NAMES =&lt;br /&gt;
| SHORT DESCRIPTION = British mathematician and physicist&lt;br /&gt;
| DATE OF BIRTH     = April 21, 1851&lt;br /&gt;
| PLACE OF BIRTH    = [[Blairgowrie and Rattray|Blairgowrie]], [[Scotland]]&lt;br /&gt;
| DATE OF DEATH     = August 28, 1913&lt;br /&gt;
| PLACE OF DEATH    = [[Chatham, Ontario]], [[Canada]]&lt;br /&gt;
}}&lt;br /&gt;
{{DEFAULTSORT:Macfarlane, Alexander}}&lt;br /&gt;
[[Category:1851 births]]&lt;br /&gt;
[[Category:1913 deaths]]&lt;br /&gt;
[[Category:People from Blairgowrie and Rattray]]&lt;br /&gt;
[[Category:Scottish mathematicians]]&lt;br /&gt;
[[Category:Scottish logicians]]&lt;br /&gt;
[[Category:Scottish physicists]]&lt;br /&gt;
[[Category:19th-century British mathematicians]]&lt;br /&gt;
[[Category:19th-century Scottish people]]&lt;br /&gt;
[[Category:20th-century mathematicians]]&lt;br /&gt;
[[Category:Academics of the University of Edinburgh]]&lt;br /&gt;
[[Category:Academics of the University of St Andrews]]&lt;br /&gt;
[[Category:Alumni of the University of Edinburgh]]&lt;br /&gt;
[[Category:Fellows of the Royal Society of Edinburgh]]&lt;br /&gt;
[[Category:Lehigh University faculty]]&lt;br /&gt;
[[Category:People from Chatham-Kent]]&lt;br /&gt;
[[Category:Relativists]]&lt;br /&gt;
[[Category:Scottish expatriates in the United States]]&lt;br /&gt;
[[Category:Scottish emigrants to Canada]]&lt;br /&gt;
[[Category:University of Texas at Austin faculty]]&lt;br /&gt;
[[Category:ICM 1900 Plenary and Invited Speakers]]&lt;br /&gt;
[[Category:Geometers]]&lt;br /&gt;
[[Category:Scottish philosophers]]&lt;/div&gt;</summary>
		<author><name>en&gt;ChrisGualtieri</name></author>
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