Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

This book collects the notes of the lectures given at the Advanced Course on Crossed Products, Groupoids, and Rokhlin dimension, that took place at the Centre de Recerca Matematica (CRM) from March 13 to March 17, 2017. The notes consist of three series of lectures. The first one was given by Dana Williams (Dartmouth College), and served as an introduction to crossed products of C*-algebras and the study of their structure. The second series of lectures was delivered by Aidan Sims (Wollongong), who gave an overview of the theory of topological groupoids (as a model for groups and group actions) and groupoid C*-algebras, with particular emphasis on the case of etale groupoids. Finally, the last series was delivered by Gabor Szabo (Copenhagen), and consisted of an introduction to Rokhlin type properties (mostly centered around the work of Hirshberg, Winter and Zacharias) with hints to the more advanced theory related to groupoids.

Dana Williams made a remarkable discovery: the individual phrases of the Lord's Prayer fit perfectly into the 7 chakras and the 12 archetypal paths of life. Out of this discovery developed a unique prayer-meditation. Williams writes, "Each phrase of the Lord's Prayer fits into a chakra like a key into a lock. By reciting each phrase within its chakra, we create an impulse or evocation that brings us into harmony with Spirit's intention for our growth. The Lord's Prayer prayer-meditation begins at the highest chakra of pure Christ Consciousness. This highest energetic quality descends into the lower chakras as we continue with the prayer. This brings the impulse of spirituality into all the charkas, clearing and transforming the patterns of ego that block the impulse of Spirit in our life. If you start a practice when you are young and keep it up over many years, even if you periodically neglect it, the practice will grow, change and deepen. After 35 years, I now have much to share about this special visualization and prayer-meditation that I believe spans the arch of eastern and western religion. For whom is this book written? For all who are interested in the correlations and prayer-meditations described here, and who treasure the Christian traditions. If you know how to work sincerely with prayer, this meditation should have an immediate effect. The purpose of this book is to open the door to this experience."