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Mixed-Layer Clay Geothermometry in the Wairakei Geothermal Field, New Zealand
- Colin Charles Harvey, Patrick R. L. Browne
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- Journal:
- Clays and Clay Minerals / Volume 39 / Issue 6 / December 1991
- Published online by Cambridge University Press:
- 02 April 2024, pp. 614-621
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Mixed-layer clays of variable composition and structure occur in core samples from two drillholes (WK207 and WK210) drilled into the Te Mihi sector of the Wairakei geothermal field. These were identified by X-ray diffraction analysis of glycolated and oriented sample fractions at less than 2 μm and less than 0.2 μm.
Low permeability lacustrine sediments encountered by drillhole WK207 contain a well-developed sequence of mixed-layer clays. The shallowest downhole appearance of mixed-layered illite/smectite (I0.6/Sm) occurs at 146 m depth where temperature is only 100°C. Discrete illite is present only below 297 m (200°C) in the finer size fraction (less than 0.2 ¼m). Chlorite first appears downhole, in association with illite-smectite, at 177 m depth (110°C).
Drillhole WK210 encountered predominantly ignimbrites and rhyolites, and fluid flow here is mainly in channels. Within these rocks, a sequence of interlayered clays is poorly developed. Discrete illite and chlorite are present in core from only 244 m (180°), but the measured temperatures where interlayer clays occur ranges from 140 to 209°C.
Differences in the identity of clay minerals present in the Wairakei reservoir, where conditions are otherwise the same, demonstrate the strong control that the type of fluid flow has on their formation. In poorly-permeable sediments, where diffuse fluid flow prevails, a clearly-defined sequence of mixed-layer clays occurs. These are absent where channel flow dominates, the discrete chlorite and illite deposit directly from solution.
7 - Do Symmetries ‘Explain’ Conservation Laws? The Modern Converse Noether Theorem vs Pragmatism
- Edited by James Read, Pembroke College, Oxford, Nicholas J. Teh, University of Notre Dame, Indiana
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- Book:
- The Philosophy and Physics of Noether's Theorems
- Published online:
- 22 September 2022
- Print publication:
- 29 September 2022, pp 144-168
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Summary
Noether’s first theorem, in its modern form, does not establish a one-way explanatory arrow from symmetries to conservation laws, but such an arrow is widely assumed in discussions of the theorem in the physics and philosophy literature. It is argued here that there are pragmatic reasons for privileging symmetries, even if they do not strictly justify explanatory priority. To this end, some practical factors are adduced as to why Noether’s direct theorem seems to be more well-known and exploited than its converse, with special attention being given to the sometimes overlooked nature of Noether’s converse result and to its strengthened version due to Luis Martínez Alonso in 1979 and independently Peter Olver in 1986.
Advanced Phase Reconstruction Methods Enabled by Four-Dimensional Scanning Transmission Electron Microscopy
- Colin Ophus, Tyler R Harvey, Fehmi S Yasin, Hamish G Brown, Philipp M Pelz, Benjamin H Savitzky, Jim Ciston, Benjamin J McMorran
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- Journal:
- Microscopy and Microanalysis / Volume 25 / Issue S2 / August 2019
- Published online by Cambridge University Press:
- 05 August 2019, pp. 10-11
- Print publication:
- August 2019
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ASKAP commissioning observations of the GAMA 23 field
- Part of
- Denis A. Leahy, A. M. Hopkins, R. P. Norris, J. Marvil, J. D. Collier, E. N. Taylor, J. R. Allison, C. Anderson, M. Bell, M. Bilicki, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, S. Driver, G. Gurkan, L. Harvey-Smith, I. Heywood, B. W. Holwerda, J. Liske, A. R. Lopez-Sanchez, D. McConnell, A. Moffett, M. S. Owers, K. A. Pimbblet, W. Raja, N. Seymour, M. A. Voronkov, L. Wang
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 36 / 2019
- Published online by Cambridge University Press:
- 19 July 2019, e024
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We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
6 - Bell on Bell's Theorem: The Changing Face of Nonlocality
- from Part II - Bell's Theorem
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- By Harvey R. Brown, University of Oxford, Christopher G. Timpson, University of Oxford
- Edited by Mary Bell, Shan Gao, Chinese Academy of Sciences, Beijing
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- Book:
- Quantum Nonlocality and Reality
- Published online:
- 05 September 2016
- Print publication:
- 19 September 2016, pp 91-123
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Summary
Abstract
Between 1964 and 1990, the notion of nonlocality in Bell's papers underwent a profound change as his nonlocality theorem gradually became detached from quantum mechanics, and referred to wider probabilistic theories involving correlations between separated beables. The proposition that standard quantum mechanics is itself nonlocal (more precisely, that it violates ‘local causality’) became divorced from the Bell theorem per se from 1976 on, although this important point is widely overlooked in the literature. In 1990, the year of his death, Bell would express serious misgivings about themathematical form of the local causality condition and leave ill-defined the issue of the consistency between special relativity and violation of the Bell-type inequality. In our view, the significance of the Bell theorem, in both its deterministic and stochastic forms, can only be fully understood by taking into account the fact that a fully Lorentz covariant version of quantum theory, free of action at a distance, can be articulated in the Everett interpretation.
Introduction
John S. Bell's last word on his celebrated nonlocality theorem and its interpretation appeared in his 1990 paper ‘La nouvelle cuisine’, first published in the year of his untimely death. Bell was careful here to distinguish between the issue of ‘no superluminal signalling’ in quantum theory (both quantum field theory and quantum mechanics) and a principle he first introduced explicitly in 1976 and called ‘local causality’ [1]. In relation to the former, Bell expressed concerns that amplify doubts he had already expressed in 1976. These concerns touch on what is now widely known as the no-signalling theorem in quantum mechanics, and ultimately have to do with Bell's distaste for what he saw as an anthropocentric element in orthodox quantum thinking. In relation to local causality, Bell emphasised that his famous factorizability (no-correlations) condition is not to be seen ‘as the formulation of local causality, but as a consequence thereof’ and stressed how difficult he found it to articulate this consequence. He left the question of any strict inconsistency between violation of factorizability and special relativity theory unresolved, a not insignificant shift from his thinking up to the early 1980s.
The Australian Square Kilometre Array Pathfinder: Performance of the Boolardy Engineering Test Array
- Part of
- D. McConnell, J. R. Allison, K. Bannister, M. E. Bell, H. E. Bignall, A. P. Chippendale, P. G. Edwards, L. Harvey-Smith, S. Hegarty, I. Heywood, A. W. Hotan, B. T. Indermuehle, E. Lenc, J. Marvil, A. Popping, W. Raja, J. E. Reynolds, R. J. Sault, P. Serra, M. A. Voronkov, M. Whiting, S. W. Amy, P. Axtens, L. Ball, T. J. Bateman, D. C.-J. Bock, R. Bolton, D. Brodrick, M. Brothers, A. J. Brown, J. D. Bunton, W. Cheng, T. Cornwell, D. DeBoer, I. Feain, R. Gough, N. Gupta, J. C. Guzman, G. A. Hampson, S. Hay, D. B. Hayman, S. Hoyle, B. Humphreys, C. Jacka, C. A. Jackson, S. Jackson, K. Jeganathan, J. Joseph, B. S. Koribalski, M. Leach, E. S. Lensson, A. MacLeod, S. Mackay, M. Marquarding, N. M. McClure-Griffiths, P. Mirtschin, D. Mitchell, S. Neuhold, A. Ng, R. Norris, S. Pearce, R. Y. Qiao, A. E. T. Schinckel, M. Shields, T. W. Shimwell, M. Storey, E. Troup, B. Turner, J. Tuthill, A. Tzioumis, R. M. Wark, T. Westmeier, C. Wilson, T. Wilson
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 33 / 2016
- Published online by Cambridge University Press:
- 09 September 2016, e042
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We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
The Australian Square Kilometre Array Pathfinder: System Architecture and Specifications of the Boolardy Engineering Test Array
- A. W. Hotan, J. D. Bunton, L. Harvey-Smith, B. Humphreys, B. D. Jeffs, T. Shimwell, J. Tuthill, M. Voronkov, G. Allen, S. Amy, K. Ardern, P. Axtens, L. Ball, K. Bannister, S. Barker, T. Bateman, R. Beresford, D. Bock, R. Bolton, M. Bowen, B. Boyle, R. Braun, S. Broadhurst, D. Brodrick, K. Brooks, M. Brothers, A. Brown, C. Cantrall, G. Carrad, J. Chapman, W. Cheng, A. Chippendale, Y. Chung, F. Cooray, T. Cornwell, E. Davis, L. de Souza, D. DeBoer, P. Diamond, P. Edwards, R. Ekers, I. Feain, D. Ferris, R. Forsyth, R. Gough, A. Grancea, N. Gupta, J. C. Guzman, G. Hampson, C. Haskins, S. Hay, D. Hayman, S. Hoyle, C. Jacka, C. Jackson, S. Jackson, K. Jeganathan, S. Johnston, J. Joseph, R. Kendall, M. Kesteven, D. Kiraly, B. Koribalski, M. Leach, E. Lenc, E. Lensson, L. Li, S. Mackay, A. Macleod, T. Maher, M. Marquarding, N. McClure-Griffiths, D. McConnell, S. Mickle, P. Mirtschin, R. Norris, S. Neuhold, A. Ng, J. O’Sullivan, J. Pathikulangara, S. Pearce, C. Phillips, R. Y. Qiao, J. E. Reynolds, A. Rispler, P. Roberts, D. Roxby, A. Schinckel, R. Shaw, M. Shields, M. Storey, T. Sweetnam, E. Troup, B. Turner, A. Tzioumis, T. Westmeier, M. Whiting, C. Wilson, T. Wilson, K. Wormnes, X. Wu
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 31 / 2014
- Published online by Cambridge University Press:
- 13 November 2014, e041
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This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Contributors
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- By Michael H. Allen, Leora Amira, Victoria Arango, David W. Ayer, Helene Bach, Christopher R. Bailey, Ross J. Baldessarini, Kelsey Ball, Alan L. Berman, Marian E. Betz, Emily A. Biggs, R. Warwick Blood, Kathleen T. Brady, David A. Brent, Jeffrey A. Bridge, Gregory K. Brown, Anat Brunstein Klomek, A. Jacqueline Buchanan, Michelle J. Chandley, Tim Coffey, Jessica Coker, Yeates Conwell, Scott J. Crow, Collin L. Davidson, Yogesh Dwivedi, Stacey Espaillat, Jan Fawcett, Steven J. Garlow, Robert D. Gibbons, Catherine R. Glenn, Deborah Goebert, Erica Goldstein, Tina R. Goldstein, Madelyn S. Gould, Kelly L. Green, Alison M. Greene, Philip D. Harvey, Robert M. A. Hirschfeld, Donna Holland Barnes, Andres M. Kanner, Gary J. Kennedy, Stephen H. Koslow, Benoit Labonté, Alison M. Lake, William B. Lawson, Steve Leifman, Adam Lesser, Timothy W. Lineberry, Amanda L. McMillan, Herbert Y. Meltzer, Michael Craig Miller, Michael J. Miller, James A. Naifeh, Katharine J. Nelson, Charles B. Nemeroff, Alexander Neumeister, Matthew K. Nock, Jennifer H. Olson-Madden, Gregory A. Ordway, Michael W. Otto, Ghanshyam N. Pandey, Giampaolo Perna, Jane Pirkis, Kelly Posner, Anne Rohs, Pedro Ruiz, Molly Ryan, Alan F. Schatzberg, S. Charles Schulz, M. Katherine Shear, Morton M. Silverman, April R. Smith, Marcus Sokolowski, Barbara Stanley, Zachary N. Stowe, Sarah A. Struthers, Leonardo Tondo, Gustavo Turecki, Robert J. Ursano, Kimberly Van Orden, Anne C. Ward, Danuta Wasserman, Jerzy Wasserman, Melinda K. Westlund, Tracy K. Witte, Kseniya Yershova, Alexandra Zagoloff, Sidney Zisook
- Edited by Stephen H. Koslow, University of Miami, Pedro Ruiz, University of Miami, Charles B. Nemeroff, University of Miami
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- Book:
- A Concise Guide to Understanding Suicide
- Published online:
- 05 October 2014
- Print publication:
- 18 September 2014, pp vii-x
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- By Núria Duran Adroher, Sergio Aguilar-Gaxiola, Jordi Alonso, Ali Obaid Al-Hamzawi, Laura Helena Andrade, Matthias C. Angermeyer, James Anthony, Corina Benjet, Guilherme Borges, Joshua Breslau, Evelyn J. Bromet, Ronny Bruffaerts, Brendan Bunting, Huibert Burger, José Miguel Caldas de Almeida, Graça Cardoso, Somnath Chatterji, Wai Tat Chiu, Giovanni de Girolamo, Ron de Graaf, Peter de Jonge, Koen Demyttenaere, John Fayyad, Alize J. Ferrari, Silvia Florescu, Anne M. Gadermann, Meyer Glantz, Jen Green, Michael J. Gruber, Oye Gureje, Josep Maria Haro, Yanling He, Steven G. Heeringa, Hristo Hinkov, Chiyi Hu, Yueqin Huang, Irving Hwang, Robert Jin, Elie G. Karam, Norito Kawakami, Ronald C. Kessler, Lola Kola, Viviane Kovess-Masféty, Michael C. Lane, Carmen Lara, William LeBlanc, Sing Lee, Jean-Pierre Lépine, Daphna Levinson, Zhaorui Liu, Gustavo Loera, Herbert Marschinger, Katie A. McLaughlin, Maria Elena Medina-Mora, Elizabeth Miller, Samuel D. Murphy, Aimee Nasser Karam, Matthew K. Nock, Mark A. Oakley Browne, Siobhan O’Neill, Johan Ormel, Beth-Ellen Pennell, Maria V. Petukhova, José Posada-Villa, Rajesh Sagar, Mohammad Salih Khalaf, Nancy A. Sampson, Kathleen Saunders, Michael Schoenbaum, Kate M. Scott, Soraya Seedat, Victoria Shahly, Dan J. Stein, Hisateru Tachimori, Nezar Ismet Taib, Adley Tsang, T. Bedirhan Üstün, Maria Carmen Viana, Gemma Vilagut, Michael R. Von Korff, J. Elisabeth Wells, Harvey A. Whiteford, David R. Williams, Ben Wu, Miguel Xavier, Alan M. Zaslavsky
- Edited by Jordi Alonso, Universitat Pompeu Fabra, Barcelona, Somnath Chatterji, World Health Organization, Geneva, Yanling He
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- Book:
- The Burdens of Mental Disorders
- Print publication:
- 09 May 2013, pp ix-xii
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Science with the Murchison Widefield Array
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- Judd D. Bowman, Iver Cairns, David L. Kaplan, Tara Murphy, Divya Oberoi, Lister Staveley-Smith, Wayne Arcus, David G. Barnes, Gianni Bernardi, Frank H. Briggs, Shea Brown, John D. Bunton, Adam J. Burgasser, Roger J. Cappallo, Shami Chatterjee, Brian E. Corey, Anthea Coster, Avinash Deshpande, Ludi deSouza, David Emrich, Philip Erickson, Robert F. Goeke, B. M. Gaensler, Lincoln J. Greenhill, Lisa Harvey-Smith, Bryna J. Hazelton, David Herne, Jacqueline N. Hewitt, Melanie Johnston-Hollitt, Justin C. Kasper, Barton B. Kincaid, Ronald Koenig, Eric Kratzenberg, Colin J. Lonsdale, Mervyn J. Lynch, Lynn D. Matthews, S. Russell McWhirter, Daniel A. Mitchell, Miguel F. Morales, Edward H. Morgan, Stephen M. Ord, Joseph Pathikulangara, Thiagaraj Prabu, Ronald A. Remillard, Timothy Robishaw, Alan E. E. Rogers, Anish A. Roshi, Joseph E. Salah, Robert J. Sault, N. Udaya Shankar, K. S. Srivani, Jamie B. Stevens, Ravi Subrahmanyan, Steven J. Tingay, Randall B. Wayth, Mark Waterson, Rachel L. Webster, Alan R. Whitney, Andrew J. Williams, Christopher L. Williams, J. Stuart B. Wyithe
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 30 / 2013
- Published online by Cambridge University Press:
- 16 April 2013, e031
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Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
Contributors
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- By James Ahn, Eric L. Anderson, Annette L. Beautrais, Dennis Beedle, Jon S. Berlin, Benjamin L. Bregman, Peter Brown, Suzie Bruch, Jonathan Busko, Stuart Buttlaire, Laurie Byrne, Gerald Carroll, Valerie A. Carroll, Margaret Cashman, Joseph R. Check, Lara G. Chepenik, Robert N. Cuyler, Preeti Dalawari, Suzanne Dooley-Hash, William R. Dubin, Mila L. Felder, Avrim B. Fishkind, Reginald I. Gaylord, Rachel Lipson Glick, Travis Grace, Clare Gray, Anita Hart, Ross A. Heller, Amanda E. Horn, David S. Howes, David C. Hsu, Andy Jagoda, Margaret Judd, John Kahler, Daryl Knox, Gregory Luke Larkin, Patricia Lee, Jerrold B. Leikin, Eddie Markul, Marc L. Martel, J. D. McCourt, MaryLynn McGuire Clarke, Mark Newman, Anthony T. Ng, Barbara Nightengale, Kimberly Nordstrom, Jagoda Pasic, Jennifer Peltzer-Jones, Marcia A. Perry, Larry Phillips, Paul Porter, Seth Powsner, Michael S. Pulia, Erin Rapp, Divy Ravindranath, Janet S. Richmond, Silvana Riggio, Harvey L. Ruben, Derek J. Robinson, Douglas A. Rund, Omeed Saghafi, Alicia N. Sanders, Jeffrey Sankoff, Lorin M. Scher, Louis Scrattish, Richard D. Shih, Maureen Slade, Susan Stefan, Victor G. Stiebel, Deborah Taber, Vaishal Tolia, Gary M. Vilke, Alvin Wang, Michael A. Ward, Joseph Weber, Michael P. Wilson, James L. Young, Scott L. Zeller
- Edited by Leslie S. Zun
- Edited in association with Lara G. Chepenik, Mary Nan S. Mallory
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- Book:
- Behavioral Emergencies for the Emergency Physician
- Published online:
- 05 April 2013
- Print publication:
- 21 March 2013, pp viii-xii
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. 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Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
- Print publication:
- 20 September 2010, pp xi-xliv
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Contributors
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- By Joëlle Adrien, M. Y. Agargun, Negar Ahmadi, Imran M. Ahmed, J. Todd Arnedt, Joseph Barbera, Simon Beaulieu-Bonneau, Marie E. Beitinger, Francesco Benedetti, Glenn Berall, Kirk J. Brower, Gregory M. Brown, Kumaraswamy Budur, Daniel P. Cardinali, Deirdre A. Conroy, Sara Dallaspezia, José Manuel de la Fuente, Paolo De Luca, Diana De Ronchi, Antonio Drago, Matthew R. Ebben, Irshaad Ebrahim, Pingfu Feng, Peter B. Fenwick, Lina Fine, Jonathan Adrian Ewing Fleming, Paul A. Fredrickson, Stephany Fulda, Lucile Garma, Roger Godbout, Reut Gruber, J. Allan Hobson, Andrea Iaboni, Anna Ivanenko, Mayumi Kimura, Milton Kramer, Christoph J. Lauer, Remy Luthringer, Luis Fernando Martínez, Sara Matteson-Rusby, Robert W. McCarley, Charles J. Meliska, Harvey Moldofsky, Charles M. Morin, Sricharan Moturi, Marie-Christine Ouellet, James F. Pagel, S. R. Pandi-Perumal, Barbara L. Parry, Timo Partonen, Wilfred R. Pigeon, Thomas Pollmächer, Nathalie Pross, Elliott Richelson, Naomi L. Rogers, Stefan Rupprecht-Mrozek, Philip Saleh, Andreas Schuld, Alessandro Serretti, Colin M. Shapiro, Christopher Michael Sinton, Marcel G. Smits, D. Warren Spence, Jürgen Staedt, Corinne Staner, Luc Staner, Axel Steiger, Deborah Suchecki, Michael J. Thorpy, Inna Voloh, Bradley G. Whitwell, Robert A. Zucker
- Edited by S. R. Pandi-Perumal, Milton Kramer, University of Illinois, Chicago
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- Sleep and Mental Illness
- Published online:
- 05 July 2011
- Print publication:
- 01 April 2010, pp ix-xiii
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- By Graham Allan, Donna M. Allen, Irwin Altman, Arthur Aron, Donald H. Baucom, Steven R. H. Beach, Ellen Berscheid, Rosemary Blieszner, Jeffrey Boase, Tyfany M. J. Boettcher, Barbara B. Brown, Abraham P. Buunk, Lorne Campbell, Daniel J. Canary, Rodney Cate, John P. Caughlin, Mahnaz Charania, Jennie Y. Chen, F. Scott Christopher, Jennifer A. Clarke, Marilyn Coleman, W. Andrew Collins, Michael K. Coolsen, Nathan R. Cottle, Carolyn E. Cutrona, Marianne Dainton, Valerian J. Derlega, Lisa M. Diamond, Pieternel Dijkstra, Steve Duck, Pearl A. Dykstra, Norman B. Epstein, Beverley Fehr, Frank D. Fincham, Helen E. Fisher, Julie Fitness, Garth J. O. Fletcher, Myron D. Friesen, Lawrence Ganong, Kelli A. Gardner, Jenny de Jong Gierveld, Robin Goodwin, Christine R. Gray, Kathryn Greene, David W. Harris, Willard W. Hartup, John H. Harvey, Kathi L. Heffner, Ted L. Huston, William J. Ickes, Emily A. Impett, Michael P. Johnson, Deborah J. Jones, Deborah A. Kashy, Janice K. Kiecolt‐Glaser, Jeffrey L. Kirchner, Brighid M. Kleinman, Galena H. Kline, Mark L. Knapp, Ascan Koerner, Jean‐Philippe Laurenceau, Kim Leon, Timothy J. Loving, Stephanie D. Madsen, Howard J. Markman, Alicia Mathews, Mario Mikulincer, Patricia Noller, Nickola C. Overall, Letitia Anne Peplau, Daniel Perlman, Sally Planalp, Urmila Pillay, Nicole D. Pleasant, Caryl E. Rusbult, Barbara R. Sarason, Irwin G. Sarason, Phillip R. Shaver, Alan L. Sillars, Jeffry A. Simpson, Susan Sprecher, Susan Stanton, Greg Strong, Catherine A. Surra, Anita L. Vangelisti, C. Arthur VanLear, Theo van Tilburg, Barry Wellman, Amy Wenzel, Carol M. Werner, Adam R. West, Sarah W. Whitton, Heike A. Winterheld
- Edited by Anita L. Vangelisti, University of Texas, Austin, Daniel Perlman, University of British Columbia, Vancouver
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- The Cambridge Handbook of Personal Relationships
- Published online:
- 05 June 2012
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- 05 June 2006, pp xvii-xxii
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5 - Symmetries and Noether's theorems
- Edited by Katherine Brading, Wolfson College, Oxford, Elena Castellani, Università degli Studi, Florence
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- Symmetries in Physics
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- 08 October 2009
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- 04 December 2003, pp 89-109
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Summary
Introduction
Emmy Noether's greatest contributions to science were in algebra, but for physicists her name will always be remembered for her paper of 1918 on an invariance problem in the calculus of variations. The most celebrated part of this work, associated with her ‘first theorem’, has to do with the connection between continuous (global) symmetries in Lagrangian dynamics and conservation principles, though the main focus of the paper was the relationship between this and the second part of her paper, where she gives a systematic treatment of the more subtle and general case of continuous local symmetries (symmetries depending on arbitrary functions of the spacetime coordinates).
The connection between global or ‘rigid’ symmetries and conservation principles in classical mechanics was hardly news in 1918. As Kastrup (1987) discusses in his historical review, it had been appreciated in the previous century by Lagrange, Hamilton, Jacobi, and Poincaré, and an anticipation of Noether's first theorem in the special cases of the 10-parameter Lorentz and Galilean groups had been given by Herglotz in 1911 and Engel in 1916, respectively. Noether's own contribution is often praised for its degree of generality, and not without reason. But interestingly it does not cover the cases in which the symmetry transformation preserves the Lagrangian or Lagrangian density only up to a divergence term. It does not therefore cover such cases as the boost symmetry in classical pre-relativistic dynamics, although modern treatments of Noether's first theorem commonly rectify this defect.
11 - The origin of the spacetime metric: Bell's ‘Lorentzian pedagogy’ and its significance in general relativity
- Edited by Craig Callender, Nick Huggett, University of Illinois, Urbana-Champaign
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- Book:
- Physics Meets Philosophy at the Planck Scale
- Published online:
- 15 December 2009
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- 29 January 2001, pp 256-272
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Summary
Introduction
In 1976, J.S. Bell published a paper on ‘How to teach special relativity’ (Bell 1976). The paper was reprinted a decade later in his well-known book Speakable and unspeakable in quantum mechanics – the only essay to stray significantly from the theme of the title of the book. In the paper Bell was at pains to defend a dynamical treatment of length contraction and time dilation, following ‘very much the approach of H.A. Lorentz’ (Bell 1987, p. 77).
Just how closely Bell stuck to Lorentz's thinking in this connection is debatable. We shall return to this question shortly. In the meantime, we briefly rehearse the central points of Bell's rather unorthodox argument.
Bell considered a single atom modelled by an electron circling a more massive nucleus, ignoring the back-effect of the field of the electron on the nucleus. The question he posed was: what is the prediction in Maxwell's electrodynamics (taken to be valid in the frame relative to which the nucleus is initially at rest) as to the effect on the electron orbit when the nucleus is set (gently) in motion in the plane of the orbit? Using only Maxwell's field equations, the Lorentz force law and the relativistic formula linking the electron's momentum and its velocity – which Bell attributed to Lorentz – he concluded that the orbit undergoes the familiar longitudinal (‘Fitzgerald’ (sic)) contraction, and its period changes by the familiar (‘Larmor’) dilation.
When is a Physical Theory Relativistic?
- Roland Sypel, Harvey R. Brown
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- Journal:
- PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association / Volume 1992 / Issue 1 / 1992
- Published online by Cambridge University Press:
- 28 February 2022, pp. 507-514
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- 1992
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It may be thought that the question ‘when is a physical theory relativistic?’ has a fairly straightforward answer, namely: ‘when it is Galilean invariant’ (for classical mechanics) or ‘Lorentz invariant’ (for special relativity). In the context of the modern ‘spacetime theory’ approach to relativity physics, the answer is more elaborate, in the interests of greater precision. In this paper, we examine two recent discussions of the issue, or aspects of it, found in a 1990 paper of Arntzenius and the well-known 1983 study of Friedman.
Arntzenius constructs a ‘sure-fire method’ of constructing a Lorentz invariant spacetime theory from a non Lorentz invariant one. We argue that if the original theory is anything like a typical dynamical theory in physics, its ‘completeness’—in a sense to be defined—will render the new theory underdetermined.
Discussion: Does The Principle of Relativity Imply Winnie's (1970) Equal Passage Times Principle?
- Harvey R. Brown
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- Journal:
- Philosophy of Science / Volume 57 / Issue 2 / June 1990
- Published online by Cambridge University Press:
- 01 April 2022, pp. 313-324
- Print publication:
- June 1990
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The kinematical principle of Equal Passage Times (EPT) was introduced by Winnie in his 1970 derivation of the relativistic coordinate transformations compatible with arbitrary synchrony conventions in one-dimensional space. In this paper, the claim by Winnie and later Giannoni that EPT is a direct consequence of the relativity principle is questioned. It is shown that EPT, given Einstein's 1905 postulates, is equivalent to the relativistic (synchrony independent) clock retardation principle, and that for standard synchrony it reduces to an isotropy condition for contraction (and dilation) effects.