For questions about the scientific discipline that concerns itself with analyzing the laws of nature in full generality. It is one of the largest branches of natural science. Before applying this tag to a question, please consider using the "theoretical-physics" or "experimental-physics" tags instead, as they are more descriptive.
If the concerned question is about a more specific area of Physics (such as particle-physics, quantum-mechanics, electromagnetism etc.), this tag should be used along with the tag of that specific area of Physics. Using this tag along with theoretical-physics and/or experimental-physics should also be considered.