Working paper 1011 views
Copenhagen Quantum Mechanics
Timothy Hollowood 
Swansea University Author:
Timothy Hollowood
Abstract
In our quantum mechanics courses, measurement is usually taught in passing, as an ad-hoc procedure involving the ugly collapse of the wave function. No wonder we search for more satisfying alternatives to the Copenhagen interpretation. But this overlooks the fact that the approach fits very well wit...
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2015
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http://inspirehep.net/record/1402637 |
| URI: | https://cronfa.swan.ac.uk/Record/cronfa28515 |
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<?xml version="1.0"?><rfc1807><datestamp>2016-06-03T14:36:04.1519866</datestamp><bib-version>v2</bib-version><id>28515</id><entry>2016-06-03</entry><title>Copenhagen Quantum Mechanics</title><swanseaauthors><author><sid>ea9ca59fc948276ff2ab547e91bdf0c2</sid><ORCID>0000-0002-3258-320X</ORCID><firstname>Timothy</firstname><surname>Hollowood</surname><name>Timothy Hollowood</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2016-06-03</date><deptcode>SPH</deptcode><abstract>In our quantum mechanics courses, measurement is usually taught in passing, as an ad-hoc procedure involving the ugly collapse of the wave function. No wonder we search for more satisfying alternatives to the Copenhagen interpretation. But this overlooks the fact that the approach fits very well with modern measurement theory with its notions of the conditioned state and quantum trajectory. In addition, what we know of as the Copenhagen interpretation is a later 1950's development and some of the earlier pioneers like Bohr did not talk of wave function collapse. In fact, if one takes these earlier ideas and mixes them with later insights of decoherence, a much more satisfying version of Copenhagen quantum mechanics emerges, one for which the collapse of the wave function is seen to be a harmless book keeping device. Along the way, we explain why chaotic systems lead to wave functions that spread out quickly on macroscopic scales implying that Schrodinger cat states are the norm rather than curiosities generated in physicists' laboratories. We then describe how the conditioned state of a quantum system depends crucially on how the system is monitored illustrating this with the example of a decaying atom monitored with a time of arrival photon detector, leading to Bohr's quantum jumps. On the other hand, other kinds of detection lead to much smoother behaviour, providing yet another example of complementarity. Finally we explain how classical behaviour emerges, including classical mechanics but also</abstract><type>Working paper</type><journal/><publisher/><keywords/><publishedDay>30</publishedDay><publishedMonth>11</publishedMonth><publishedYear>2015</publishedYear><publishedDate>2015-11-30</publishedDate><doi/><url>http://inspirehep.net/record/1402637</url><notes/><college>COLLEGE NANME</college><department>Physics</department><CollegeCode>COLLEGE CODE</CollegeCode><DepartmentCode>SPH</DepartmentCode><institution>Swansea University</institution><apcterm/><lastEdited>2016-06-03T14:36:04.1519866</lastEdited><Created>2016-06-03T14:36:04.1519866</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Biosciences, Geography and Physics - Physics</level></path><authors><author><firstname>Timothy</firstname><surname>Hollowood</surname><orcid>0000-0002-3258-320X</orcid><order>1</order></author></authors><documents/><OutputDurs/></rfc1807> |
| spelling |
2016-06-03T14:36:04.1519866 v2 28515 2016-06-03 Copenhagen Quantum Mechanics ea9ca59fc948276ff2ab547e91bdf0c2 0000-0002-3258-320X Timothy Hollowood Timothy Hollowood true false 2016-06-03 SPH In our quantum mechanics courses, measurement is usually taught in passing, as an ad-hoc procedure involving the ugly collapse of the wave function. No wonder we search for more satisfying alternatives to the Copenhagen interpretation. But this overlooks the fact that the approach fits very well with modern measurement theory with its notions of the conditioned state and quantum trajectory. In addition, what we know of as the Copenhagen interpretation is a later 1950's development and some of the earlier pioneers like Bohr did not talk of wave function collapse. In fact, if one takes these earlier ideas and mixes them with later insights of decoherence, a much more satisfying version of Copenhagen quantum mechanics emerges, one for which the collapse of the wave function is seen to be a harmless book keeping device. Along the way, we explain why chaotic systems lead to wave functions that spread out quickly on macroscopic scales implying that Schrodinger cat states are the norm rather than curiosities generated in physicists' laboratories. We then describe how the conditioned state of a quantum system depends crucially on how the system is monitored illustrating this with the example of a decaying atom monitored with a time of arrival photon detector, leading to Bohr's quantum jumps. On the other hand, other kinds of detection lead to much smoother behaviour, providing yet another example of complementarity. Finally we explain how classical behaviour emerges, including classical mechanics but also Working paper 30 11 2015 2015-11-30 http://inspirehep.net/record/1402637 COLLEGE NANME Physics COLLEGE CODE SPH Swansea University 2016-06-03T14:36:04.1519866 2016-06-03T14:36:04.1519866 Faculty of Science and Engineering School of Biosciences, Geography and Physics - Physics Timothy Hollowood 0000-0002-3258-320X 1 |
| title |
Copenhagen Quantum Mechanics |
| spellingShingle |
Copenhagen Quantum Mechanics Timothy Hollowood |
| title_short |
Copenhagen Quantum Mechanics |
| title_full |
Copenhagen Quantum Mechanics |
| title_fullStr |
Copenhagen Quantum Mechanics |
| title_full_unstemmed |
Copenhagen Quantum Mechanics |
| title_sort |
Copenhagen Quantum Mechanics |
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ea9ca59fc948276ff2ab547e91bdf0c2 |
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ea9ca59fc948276ff2ab547e91bdf0c2_***_Timothy Hollowood |
| author |
Timothy Hollowood |
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Timothy Hollowood |
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Working paper |
| publishDate |
2015 |
| institution |
Swansea University |
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Faculty of Science and Engineering |
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|
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facultyofscienceandengineering |
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Faculty of Science and Engineering |
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facultyofscienceandengineering |
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Faculty of Science and Engineering |
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School of Biosciences, Geography and Physics - Physics{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Biosciences, Geography and Physics - Physics |
| url |
http://inspirehep.net/record/1402637 |
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| description |
In our quantum mechanics courses, measurement is usually taught in passing, as an ad-hoc procedure involving the ugly collapse of the wave function. No wonder we search for more satisfying alternatives to the Copenhagen interpretation. But this overlooks the fact that the approach fits very well with modern measurement theory with its notions of the conditioned state and quantum trajectory. In addition, what we know of as the Copenhagen interpretation is a later 1950's development and some of the earlier pioneers like Bohr did not talk of wave function collapse. In fact, if one takes these earlier ideas and mixes them with later insights of decoherence, a much more satisfying version of Copenhagen quantum mechanics emerges, one for which the collapse of the wave function is seen to be a harmless book keeping device. Along the way, we explain why chaotic systems lead to wave functions that spread out quickly on macroscopic scales implying that Schrodinger cat states are the norm rather than curiosities generated in physicists' laboratories. We then describe how the conditioned state of a quantum system depends crucially on how the system is monitored illustrating this with the example of a decaying atom monitored with a time of arrival photon detector, leading to Bohr's quantum jumps. On the other hand, other kinds of detection lead to much smoother behaviour, providing yet another example of complementarity. Finally we explain how classical behaviour emerges, including classical mechanics but also |
| published_date |
2015-11-30T03:34:42Z |
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1763751475712884736 |
| score |
11.036706 |