Physics is the study of nature, and is the science that deals with the laws of God's universe. Galileo was the first to discover and propose some of the fundamental laws of physics that we still use today. He began by studying how a ball rolled down an incline and showed that its speed would be proportional to the height it started at. A scientist who studies physics is called a physicist.
Newton devised many theories still commonly used in the branch of mechanics. The most famous of which, the law of gravity, was published in his notoriously difficult book entitled Principia, partly responsible for making him one of the most admired and famous scientists of all time.
Law of gravity:
This law shows how the force between any two objects (you and your laptop for instance) varies with the distance squared between the two objects.
Newton also developed the mathematical domain of Calculus: the study of rates of change. Calculus is essential to our understanding of technology around us from how electricity works to how your cell phone communicates and to the dynamics of speeding bullets and cars. Newton took around 33 years to publish this after developing it which caused a bitter feud with another mathematician of the time who also had claimed to develop it.
Another famous physicist was Ernest Rutherford who kicked off the idea of our current model of the atom. The current model, advanced by Bohr and then polished by Schrödinger dictates that all positive charge in an atom is in its nucleus (along with neutrons) and orbited by negative charge (electrons) in much the same way as planets orbit a star. In fact, to a certain extent, Newtonian dynamics can be used to describe the motion of the electron on its path around the nucleus.
Understanding the laws of physics has been the academic pursuit of many world-changing people, including the ones listed below.
Applied physicists and engineers using the laws of physics have helped develop countless technological advancements that make our world as comfortable to live in as it is today.
Many physicists and mathematicians of recent times are atheist, however this should not put you off the subject. Physics and astrophysics are the key to understanding the universe and how everything inside it operates whether God exists or not.
Other famous physicists include Aristotle, Tycho Brahe, Johannes Kepler, Carl Gauss, Isaac Newton, James Maxwell, Erwin Schroedinger, Ernest Rutherford, Werner Heisenberg, Niels Bohr, Albert Einstein, J. Robert Oppenheimer, Enrico Fermi, Richard Feynman, Joseph Taylor, Lyman Page, Leon Cooper, and James Valles, Jr.