Self-Locating Uncertainty, Subjective Probability and the Everett Interpretation

This paper analyses an attempt to reintroduce the probabilistic predictions of quantum mechanics into the Everett interpretation. An overview of the measurement problem and the Everett interpretation are first given, with particular attention paid to the issue of probability within a deterministic theory. An argument is put forth that observers in an Everettian multiverse generically experience a period of post-measurement uncertainty in regards to their location. It is further argued that this uncertainty allows pre-measurement to observers to act as if they are uncertain about future outcomes. This is then the justification for attaching probabilities to the squared moduli of the wave function. It is also noted that there is an assumption of typicality present in discussions of probability within Everett and some arguments to justify this assumption are considered

Activities of the Geographical Branch in Northern Canada, 1947-1957

The Geographical Branch of the Department of Mines and Technical Surveys was created in 1947. Under its terms of references, part of its responsibility is the collection and analysis of geographical information on northern Canada, in particular the territories under the jurisdiction of the federal government. In the decade since the Branch's inauguration, geographers have carried out various kinds of field surveys in the Canadian Arctic and subarctic, from the northern coast of Ellesmere Island to the Hudson Bay coastal plain in Ontario, and from the Alaska boundary to Labrador. These surveys have varied from parties formed entirely of geographers to individual shipboard observers or representatives on collaborative teams of scientists. The collection of basic information on the vast unknown expanses of the Arctic is peculiarly suited to the application of geographic methods. Utilizing the trimetrogon and vertical photography carried out since World War II, geographers have applied sampling techniques in interpreting larger areas, making intensive field studies of representative terrain types and expanding them by use of the air photos in delimiting, describing and analysing physiographic regions. Studies in physical geography have been the backbone of the work of the Branch in the Arctic. Air photo interpretation keys have been prepared for 14 areas: Alert, Eureka, Mould Bay, Resolute, Mackenzie Delta, Darnley Bay, Coppermine, Bathurst Inlet, Boothia Isthmus, Wager Bay, Southampton Island, Kaniapiskau-Koksoak Rivers in Ungava, the Hudson Bay Railway, and the Kenogami River. Reports on the human geography of various areas were included in the field reports and are mainly unpublished; several studies in historical geography also resulted from the field surveys. ..

Freeze-Thaw Frequencies and Mechanical Weathering in Canada

Investigates freeze-thaw cycles (a rise to 34 F following a drop to 28 F) as a cause of rock disintegration by comparing their frequencies in northern and southern Canada. Cycles counted at 42 weather stations showed an increase from north to south: nine at Eureka on Ellesmere Island in 1949 as compared with 74 at Regina, Saskatchewan. Correlation between the freeze-thaw frequencies and diurnal temperature range is indicated; average at Eureka is 12 F at Regina 24 F. The greater evidence of rock disintegration in northern Canada therefore does not result from lower temperatures or freeze-thaw frequency. Other explanations are offered

Francis Austin Cook (1918-1966)

Frank Cook, geographer and a Fellow of the Arctic Institute, died in Ottawa in March. A native of Kamloops, B.C., he served in the Canadian Army from 1941 to 1948, and earned with distinction his geography degrees from the University of British Columbia in 1952 and the University of Wisconsin in 1953. Accepted as a doctoral candidate at McGill in 1954, ill health prevented completion of his residence requirements. He taught briefly at United College in Winnipeg before joining the staff of the Geographical Branch in 1957. His previous research activities included several summers with the Geographical Branch as well as a year with the Meteorological Service at Resolute, N.W.T. His scientific contributions were mainly in periglacial geomorphology and he published several significant papers in this field in Arctic and other journals. He was firmly convinced of the importance of assembling and making available annotated bibliographies. His detailed field investigations at Resolute resulted in several important papers, including those on the relationship of soil temperatures to the formation of patterned ground, a critique of the role of freeze-thaw cycles in mechanical disintegration of rock material, and on the significance of unrecorded precipitation in the climatic regime in the Arctic. He collaborated with Professor L. E. Hamelin of Laval University in the preparation of a monograph on periglacial phenomena which is expected to appear in the near future. When increasing poor health forced him to give up field work, he became more involved in technical editing, reviewing, and contributing to the abstract journals. Besides his contributions to the development of the Geographical Bulletin, he initiated the application of data processing techniques in the Geographical Branch. It is most unfortunate that his deteriorating health kept Frank Cook from realizing his full potential as a painstaking and original researcher. Nevertheless, his broad reading in periglacial geomorphology and his concern with analysis based on quantitative measurements were always appreciated by his colleagues, to whose research he contributed by thoughtful suggestions and encouragement. His appointment to the Canadian Committee of the Periglacial Commission of the International Geographical Union illustrates his recognized authority in this field. His death at the age of 47 deprives the profession of a competent research worker and his colleagues of a valued friend

Variation of tow force with velocity during offshore ploughing in granular materials

Pipeline plough behaviour has been investigated by means of reduced scale physical model testing. A testing programme was devised to investigate the influence of permeability, relative density, and plough depth on the associated tow force measured during ploughing over a range of velocities in saturated granular material. An increase in tow force with velocity was found during all of the tests and the results have been compared to previously developed analytical models. A new empirical equation has been developed to describe the change in tow force with velocity for a variety of model siliceous sand conditions. Application of this new approach to full-scale ploughing requires consideration of scaling effects and the use of appropriate input parameters determined to replicate field conditions. </jats:p

Visualisation of fingermarks and grab impressions on fabrics. Part 1: gold/zinc vacuum metal deposition

Vacuum metal deposition (VMD) is a highly sensitive technique originally introduced for detecting latent fingermarks on smooth non-porous surfaces such as carrier bags, plastics and glass. The current study explores whether VMD can be used in the examination of clothing from physical and sexual assault cases in order to visualise identifiable fingermark ridge detail and/or palmar flexion crease detail, thus allowing potential areas to be indicated for DNA swabbing and/or to determine the sequence of events. Four different fabrics were utilised during this study – nylon, polyester, polycotton and cotton, along with 15 donors who ranged in their age and propensity to leave fingermarks, from good to medium to poor as determined by results obtained from test runs using paper and plastic carrier bags processed with VMD. Once samples were collected they were kept for a determined time (1, 2, 3, 4, 5, 6, 7, 14, 21 or 28 days) and then treated using the gold/zinc metal VMD process. From the results, it appears that greater ridge detail is visible on the smoother non-porous fabrics, such as nylon whereas on rougher porous fabrics, such as cotton, only empty prints and impressions, rather than any ridge details, were visible. All fabrics did however allow the development of touch marks that could be targeted for DNA taping thus potentially leading to a DNA profile and possible identification of a suspect

Visualisation of fingermarks and grab impressions on dark fabrics using silver vacuum metal deposition

Vacuum metal deposition (VMD) involves the thermal evaporation of metal (silver) in a vacuum, resulting in a uniform layer being deposited on the specimen being treated. This paper examines the use of silver on dark fabrics, thus offering a simpler operation and more obvious colouration to that of the traditional use of gold and zinc metals which must be evaporated separately. The aim of this study was to investigate the effect of fabric type, donor, mark age and method of fingermark deposition on the quality of marks visualised using silver VMD. This was achieved by collecting fingermark deposits from fifteen donors, of both sexes and various ages, by a grab or a press method. Four different fabrics: satin, polyester, polycotton and cotton were studied over a 10 day timeline of 1, 2, 3, 4, 5, 6, 7, 14, 21 and 28 + days. It was found that satin and polyester gave the most positive results, with polyester often producing excellent ridge detail. Cotton and polycotton were less successful with no ridge detail being observed. The donors also had an observable effect on the results obtained probably due to variations in secretions produced or pressures applied during specimen collection. The age of the mark or the method of mark deposition had little influence on the results obtained. Silver VMD is a viable process for visualising marks on certain dark fabrics and has the advantage over gold/zinc VMD in that the marks visualised are light in colour which contrasts well against the dark background