Bøger af David Walter

This thesis describes two groundbreaking measurements in the precision frontier at the LHC: the first ever differential measurement of the Z-associated single top quark (tZq) production, and the luminosity measurement using Z boson production rate for the first time in CMS. Observed only in 2018, the tZq process is of great importance in probing top quark electroweak couplings. These couplings are natural places for new phenomena to happen in the top quark sector of the standard model. Yet, they are the least explored directly. One has to obtain a firm understanding of the modeling of sensitive distributions to new top-Z interactions. The present analysis marks a major milestone in this long-term effort. All distributions relevant for new phenomena, and/or modeling of tZq, are studied in full depth using advanced Machine Learning techniques.The luminosity and its uncertainty contributes to every physics result of the experiment. The method minutely developed in this thesis provides a complementary measurement that results in a significant overall reduction of uncertainties.

Pollution, famine, pandemic diseases, record-setting weather events, social unrest and cultural inequalities-all are the result of the collective choices humans make. Our drive to survive, combined with our unique abilities, has turned us into the greatest threat to our future. Drawing from seminal research about the rise of the Anthropocene age, David Walter presents a clear, elegant view of how we got ourselves into this conundrum. Grounded in a deep understanding of science and cultural history, Walter masterfully tells the story of how Homo sapiens moved from one challenge to the next with the best of intentions while not comprehending the consequences. Encompassing our tribal origins to our current atomic age, from the impulse to shape stones for tools to the development of internal combustion, this sweeping narrative ultimately offers a rational route toward a sustainable, livable future, and the role each of us can play in that transformation.

David Walter is one of the few people alive who participated in the birth of Alabama's artificial reef program in the mid-1980s. Information gleaned from this inaugural effort played an important part in the development of the nation's fisheries.This riveting book takes the reader through the history and process of how artificial reefs are made, as well as illustrating the many types of materials used in reef making.Readers will also learn how Walter's business is partnering with marine environment think tanks to find ways to increase oyster production, overcome problems with invasive species and improve water quality.