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My #100 course certificate from Coursera
Understanding Modern Physics I: Relativity and CosmologyThe Hong Kong University of Science and Technology I am thrilled to...
![Olbers paradox, Friedmann equation, Hubble Law, Matter](https://kzhu.ai/wp-content/uploads/2022/07/Understanding-Modern-Physics-1-18.jpg)
Cosmology
Cosmology is the science of studying our universe. Being different from astronomy, which corresponds to studying some particular...
![Equivalence principle, Light bending, Gravitational time dilation](https://kzhu.ai/wp-content/uploads/2022/07/Understanding-Modern-Physics-1-16.jpg)
General Relativity: Gravity and Black Holes
Previously, in special relativity, we have found that the concepts of space and time are relative. When you...
![Generalization of Geometry, Spacetime Diagram](https://kzhu.ai/wp-content/uploads/2022/07/Understanding-Modern-Physics-1-14.jpg)
Special Relativity: Geometry, Momentum and Energy
In 3-dimensional space, when we are looking at an object, what we see depends on the angle, the...
![Lorentz Transformation](https://kzhu.ai/wp-content/uploads/2022/06/Understanding-Modern-Physics-1-10.jpg)
Lorentz Transformation
Lorentz transformation is the central question in the mathematical structure of special relativity. Simply put, given the coordinate...
![Length contraction, Spacetime diagram, Light speedmeter](https://kzhu.ai/wp-content/uploads/2022/06/Understanding-Modern-Physics-1-5.jpg)
Special Relativity: Length and Simultaneity
The concept of “length” and “the same time” have to be reconsidered in special relativity. Light Ruler and...
![Newton's second law, Light clock, Time dilation](https://kzhu.ai/wp-content/uploads/2021/12/Understanding-Modern-Physics-1-2.jpg)
Special Relativity: Space and Time
For hundreds years, space and time were absolute in the concept of Newton, they are something that can...