This book presents peer-reviewed articles from the 1st International Conference on Trends in Modern Physics (TiMP 2021) held at Assam Don Bosco University in Guwahati, India, between February 26 and 27, 2021. This conference was the 3rd in a series of annual conferences of the Department of Physics, ADBU, with the 1st and 2nd being national conferences. The conference was jointly organized by the Department of Physics, ADBU, and the Indian Association of Physics Teachers (IAPT) to promote greater synergy between thematic areas of astrophysics and cosmology, plasma physics, material and nanophysics, nuclear physics, and particle physics