Astronomy has traditionally relied on capturing photons from cosmic sources to be able to understand the Universe. During the 20th and 21st centuries, different messengers have been added to the astronomer's toolset : cosmic rays, neutrinos, and most recently gravitational waves. Each of these messengers opens a new window on the Universe, and a modern astronomer must be familiar with them. As multimessenger astronomy becomes part of the mainstream, each messenger must be understood not only as its own astronomical domain, but as part of a whole endeavour. A broad understanding of these messengers and their relationship to each other is the main goal of this book. The unique physics of each messenger is introduced, as well as the physics of their detection and interpretation. An additional focus is the discussion of techniques and topics that are common to more than one messenger. Treatments of historical background, the effect of the Earth's atmosphere, the transfer of radiation and measurement techniques are aimed at giving the reader a broad understanding of this new way of observing the cosmos. Principles of multimessenger astronomy is designed to be both an introduction and reference to modern astronomy.

IN WRITING a book for which there is no precedent (the tistic achievements. But, alas, there has not been such last textbooks about accompanying were written during a genius in the realm of music during the twentieth the age of thorough bass or shortly thereafter - the century. The creative musical genius of our space age eighteenth and early nineteenth centuries - and dealt has yet to be discovered, if he has been born. exclusively with the problems timely then) one must Our time has perfected technique to such a degree make one's own rules and set one's own standards. This that it could not help but create perfect technician freedom makes the task somewhat easier, if, on the one artists. Our leading creative artists master technique hand, one looks to the past: there is no generally ap to the point of being able to shift from one style to proved model to be followed and to be compared with another without difficulty. Take Stravinsky and Picasso, one's work; but, on the other hand, the task is hard be for instance: they have gone back and forth through as cause one's responsibility to present and future genera many periods of style as they wished. Only with a stu tions of accompanists and coaches is great.