Astronomers have always used different wavelengths, from radio to gamma rays, in order to probe physical phenomena on small and on large scales, as well as low and high energies. However, in the past few years we also have gained access to a variety of channels that can be traced to the same objects or events: high-energy cosmic rays, neutrinos, as well as gravitational waves. Each one of these "messengers" provide different windows on black holes (BHs), neutron stars (NSs), quasars, blazars, supernovae and other sources. The complementarity of those observations is driving a new area of research on the interfaces between these traditionally separate fields, called Multi-Messenger Astrophysics (MMA).

In order to stimulate the growth of this exciting new field of research, the Principia Institute is supporting two parallel events: the Principia Institute Program on Multi-Messenger Astrophysics, and the São Paulo Advanced School on Multi-Messenger Astrophysics (also financed by FAPESP). 

The Program (May 22 - June 16/2023) will bring together a group of specialists to map out the main challenges and the opportunities for research in MMA, as well as the prospects for new discoveries in astrophysics, cosmology and fundamental physics that will come as a result of that research. It will also identify how the Brazilian physics and astronomy communities can better prepare for the new opportunities that will appear with the growing number and quality of events with multi-messenger observations. Another important aspect is the new generation of experiments and instruments that will play a role in MMA over the next decade: which of the existing projects have a higher chance of impact, and of those, in which would Brazilian researchers be able to play a significant role? And what are the capabilities of local industries to provide technological support for these projects, in terms of instrumentation or components that can be locally sourced? These questions will be addressed during the Program, which will also prepare a document ("white paper") summarizing the discussions and the main conclusions.

The Advanced School (May 29 - June 7/2023) is designed to introduce MMA to young researchers interested in this exciting new field. It will offer 6 introductory courses to approximately 100 students and postdocs, including lectures, hands-on sessions, presentations by the students, as well as a few scientific talks by some of the participants of the Program. We are also happy to announce that FAPESP will provide some level of financial support for students, both from Brazil and from other countries, to attend the Advanced School.