452 research outputs found
Identity and uncertainty in Everett's multiverse
No full textIn the current debate on the concept of probability in the Everett interpretation of quantum mechanics Saunders and Wallace argue for a notion of pre-measurement uncertainty whilst Greaves and Myrvold attempt to do without uncertainty altogether. Both these approaches are controversial and I suggest a middle way. I develop in detail an argument which Wallace has hinted at and Greaves has seen as beside the point in order to show that Vaidman’s concept of post-measurement uncertainty has more relevance to pre-measurement decision making than has hitherto been generally recognised. Further, Vaidman uncertainty leads naturally to another form of post-measurement uncertainty which clarifies the process of experimental confirmation of quantum mechanics in the Everett picture. I also stress the importance of Sider’s theory of transtemporal identity in making Everett’s multiverse intelligible
Spacetime symmetries and the CPT theorem
No full textThis dissertation explores several issues related to the CPT theorem.
Chapter 2 explores the meaning of spacetime symmetries in general and time reversal in particular. It is proposed that a third conception of time reversal, 'geometric time reversal', is more appropriate for certain theoretical purposes than the existing 'active' and 'passive' conceptions. It is argued that, in the case of classical electromagnetism, a particular nonstandard time reversal operation is at least as defensible as the standard view. This unorthodox time reversal operation is of interest because it is the classical counterpart of a view according to which the so-called 'CPT theorem' of quantum field theory is better called 'PT theorem'; on this view, a puzzle about how an operation as apparently non-spatio-temporal as charge conjugation can be linked to spacetime symmetries in as intimate a way as a CPT theorem would seem to suggest dissolves.
In chapter 3, we turn to the question of whether the CPT theorem is an essentially quantum-theoretic result. We state and prove a classical analogue of the CPT theorem for systems of tensor fields. This classical analogue, however, appears not to extend to systems of spinor fields. The intriguing answer to our question thus appears to be that the CPT theorem for spinors is essentially quantum-theoretic, but that the CPT theorem for tensor fields applies equally to the classical and quantum cases.
Chapter4 explores a puzzle that arises when one puts the CPT theorem alongside a standard way of understanding spacetime symmetries, according to which (latter) spacetime symmetries are to be understood in terms of background spacetime structure. The puzzle is that a 'PT theorem' amounts to a statement that the theory may not make essential use of a preferred direction of time, and this seems odd. We propose a solution to that puzzle for the case of tensor field theories.Ph.D.Includes bibliographical references (p. 102)
HLA-DPB1 supertype-associated protection from childhood leukaemia: relationship to leukaemia karyotype and implications for prevention
No full textMost childhood B cell precursor (BCP) acute lymphoblastic leukaemia (ALL) cases carry the reciprocal translocation t(12;21)(p13;q22) (similar to 25%), or a high hyperdiploid (HeH) karyotype (30%). The t(12;21) translocation leads to the expression of a novel fusion gene, TEL-AML1 (ETV6-RUNX1), and HeH often involves tri- and tetrasomy for chromosome 21. The presence of TEL-AML1+ and HeH cells in utero prior to the development of leukaemia suggests that these lesions play a critical role in ALL initiation. Based on our previous analysis of HLA-DP in childhood ALL, and evidence from in vitro studies that TEL-AML1 can activate HLA-DP-restricted T cell responses, we hypothesised that the development of TEL-AML1+ ALL might be influenced by the child's DPB1 genotype. To test this, we analysed the frequency of six HLA-DPB1 supertypes in a population-based series of childhood leukaemias (n = 776) classified by their karyotype (TEL-AML1+, HeH and others), in comparison with newborn controls (n = 864). One DPB1 supertype (GKD) conferred significant protection against TEL-AML1+ ALL (odds ratio (OR), 95% confidence interval (95% CI): 0.42, 0.22-0.81; p < 0.005) and HeH ALL (OR; 95% CI: 0.44, 0.30-0.65; p < 0.0001). These negative associations were almost entirely due to a single allele, DPB1*0101. Our results suggest that DPB1*0101 may afford protection from the development of TEL-AML1+ and HeH BCP ALL, possibly as the result of a DP-restricted immune response to BCP ALL-associated antigen(s), the identification of which could have important implications for the design of prophylactic vaccine
Two Views on Time Reversal
No full textIn a recent paper, Malament (2004) employs a time reversal transformation that differs from the standard one, without explicitly arguing for it. This is a new and important understanding of time reversal that deserves arguing for in its own right. I argue that it improves upon the standard one. Recent discussion has focused on whether velocities should undergo a time reversal operation. I address a prior question: What is the proper notion of time reversal? This is important, for it will affect our conclusion as to whether our best theories are time-reversal symmetric, and hence whether our spacetime is temporally oriented
Australian Author Marion Halligan - Word Artist
No full textAustralian author Marion Halligan admits that her life has been 'centred in domesticity' and this is where she draws on much of the material for her fiction. This could also be a reason why her work has been critically overlooked. Halligan is adept at capturing details of life in the domestic realm and weaving poignant, thought-provoking stories about experiences all of us can recognise in our own lives. It does not take the discerning reader long to discover the deeper considerations in her writing. According to Halligan, 'the world is a cruel and dark and difficult place and it is words that light the small candle flames that keep the dark at bay'[1]. Words and writing are essential to Halligan's life. In an essay titled 'Why I Write', she says: 'I write in order to put the world into words. I've always done that in my head. I can't perceive anything without trying to find words for it'[2]. Halligan's writing is an evocative exploration of the human condition. For Halligan, 'it is artists showing you what they see that educates the heart, in novels, in paintings, in photographs'.[3] The following essay examines three of Halligan's novels which feature an artist protagonist who is struggling to come to terms with the experience of loss, grief and bereavement. Lovers' Knots (1992), The Golden Dress (1998) and The Fog Garden (2001) are rich evocations of lives which are 'a walk with love and death ... The same subjects as the Greeks, and Shakespeare. [The] characters aren't kings and queens, aren't noble and grand, but their passions are as real'[4]
Review Of Dublin\u27s Merchant-Quaker: Anthony Sharp And The Community Of Friends, 1643-1707 By R. L. Greaves
No full textGreaves, author of several well-documented books on 17th-century dissenters, argues that Anthony Sharp (1643-1707) represents the transformation of Irish Friends from a charismatic sect into a respectable Protestant denomination. Sharp, whose father gave him several hundred pounds to begin business, ended by owning a woolen manufactory with 500 workers, at least 29 houses, and several thousand acres of land. Converted c. 1663, he became a minister, clerk and treasurer of various meetings, a controversialist who defended Friends against religious and political opponents, and a strict enforcer of the discipline. The meeting used Sharp\u27s legal training and business skills in a wide variety of activities: arbitrating between members, defending those persecuted for tithes, planning buildings, documenting persecutions, and raising money for schools. He emerges as devoted to the welfare of the Quaker community, but with no sympathy for Irish Catholics. Like George Whitehead, the leader of English Quakers after Fox\u27s death, Sharp showed little intellectual originality in his writings or activities for the meeting. Greaves\u27s account provides valuable new information about this significant sect whose Irish members numbered less than 5,000. For collections specializing in history of religion and Ireland. Upper-division undergraduates and above
Caribbean Report 29-06-1999
No full text1. Anchor Keith Stone Greaves anchors a special edition of the BBC Report on the death of Antigua’s Father of the Nation and elder statesman Sir Vere Cornwall Bird Senior. Tributes and interviews in this segment are presented by his son and current Prime Minister Lester Bird Junior, opposition leader Leonard Tim Hector, Sir Ronald Sanders Antigua and Barbuda High Commissioner to London, and politicians in the Caribbean region (01:25)2. Orin Gordon presents an extensive biographical overview of the political career and influence of Vere Bird Senior in Antigua and the wider Caribbean region (01: 26 – 15:07
Caribbean Report 20-08-1998
No full text1. Headlines (00:00-00:26)2. President Castro arrives in the Dominican Republic to a warm official welcome. Jean-Michel Caroit reports (00:27-04:22)3. A further twist in Australia's bid to get one of its citizens extradited from Spain. Finance Minister Julius Timothy and Humphrey Carter, Majorca Daily Bulletin are interviewed. Keith 'Stone' Greaves reports (04:23-08:19)4. Jamaica's Prime Minister P J Patterson has announced a date for local government elections. Opposition Leader Edward Seaga and Prime Minister P.J. Patterson are interviewed. Carol Orr reports (08:20-10:15)5. Dwight Yorke the $18 million man. Netball is beginning to make an impact in the United States. Vice President of the Caribbean Netball Association Janet Rose, Tim Beech of BBC Local Radio and Footballer Dwight Yorke are interviewed. Leslie Goffe reports (10:16-15:24
ALMA and Herschel observations of the prototype dusty and polluted white dwarf G29-38
No full textJF gratefully acknowledges the support of the STFC via an Ernest Rutherford Fellowship. AB acknowledges the support of the ANR-2010 BLAN-0505-01 (EXOZODI). MCW and OP are grateful for the support of the European Union through ERC grant number 279973.ALMA Cycle 0 and Herschel PACS observations are reported for the prototype, nearest, and brightest example of a dusty and polluted white dwarf, G29-38. These long-wavelength programmes attempted to detect an outlying, parent population of bodies at 1–100 au, from which originates the disrupted planetesimal debris that is observed within 0.01 au and which exhibits LIR/L* = 0.039. No associated emission sources were detected in any of the data down to LIR/L* ∼ 10−4, generally ruling out cold dust masses greater than 1024–1025 g for reasonable grain sizes and properties in orbital regions corresponding to evolved versions of both asteroid and Kuiper belt analogues. Overall, these null detections are consistent with models of long-term collisional evolution in planetesimal discs, and the source regions for the disrupted parent bodies at stars like G29-38 may only be salient in exceptional circumstances, such as a recent instability. A larger sample of polluted white dwarfs, targeted with the full ALMA array, has the potential to unambiguously identify the parent source(s) of their planetary debris.Peer reviewe
Map of the County of Benarba, Central Division, NSW 1907 [cartographic material] /
No full textCadastral map showing parish boundaries and land holdings.; "No of Lith. '07 306.C".; National Library of Australia's copy has handwritten annotations and highlights in red, blue and black pencil. ANL; The County of Benarba contains the following parishes: -- Balerang -- Ballalla -- Banarway -- Baroona -- Bibble -- Biroo -- Boolmuckledi -- Boomi -- Boonaldoon -- Boonangar -- Boonerey -- Boonoona -- Boronga -- Boroo -- Boyanga -- Brigalow -- Bucknel -- Bunarba -- Bundori -- Bunna Bunna -- Burragillo -- Burrandoon -- Caidmurra -- Carbeenbri -- Carraa – Collymongle [Collymungoul] -- Collyu -- Cook -- Cooloobong -- Coonalgra -- Coubal -- Cowmerton -- Crinoline -- Cudgildool -- Currah -- Currotha -- Currygundi -- Dangar -- Derra -- Dindierna -- Direlmabildi -- Doorabeeba -- Dundunga -- Galloway -- Gil Gil -- Gin -- Gingham -- Goocalla -- Gorman -- Greaves -- Greenaway -- Gunathera -- Hamilton -- Hill -- Kamilaroi -- Keelo -- Krui -- Kunopia -- Mallowa -- Markham -- Meei -- Meero -- Meroe -- Millebee -- Mongyer -- Moomin -- Moorina -- Mungi -- Myall -- Narrawall -- Neargo -- Newcastle -- Noonah -- Noora -- Numby Numby -- Oreel -- Pearse -- Pially -- Single -- Tala -- Tellaraga -- Tiela -- Tillaloo -- Turrawah -- Tycawina -- Tyrrell -- Umbri -- Uranbah -- Wadden -- Wandoona -- Warren -- Werrina -- Whalan -- Willalee -- Winslow -- Wirra North -- Wirrir South -- Wirrit -- Wolongimba -- Yarouah -- Yarrol -- Young.; Also available online http://nla.gov.au/nla.map-vn3640261
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