The puzzle of dark energy, the dark cloud of 21st centry physics, is possibly solved. A postdoctorate, Wan-Jiung Hu, solves this puzzle in his book "Theories of Everything by Logic". Wan-Jiung Hu is a MD(National Taiwan University) and PhD(Johns Hopkins University). Currently, he is a postdoctorate in Taiwan. The author is highly interested in physics research as a formal member of German Society of Physic. The author is also an associate member of American Geophysical Union.

In the book, the author propose that dark energy is actually light pressure. Photon emitted from galaxy will travel and finally reach the peripheral galaxy. Then, light pressure can cause our four dimensional universe to expansion. The logic is reasonable. The light pressure formula, according to JC Maxwell, is P=kT^4/c. In addition, there is a relation of temperature and accleration called Unruh-Hawking effect. This effect is discovered by Professors Stephen Hawking and Unruh. The relation is T=ah'/2pi*c*k. Combining light pressure formula and Unruh-Hawking effect, we can see that light pressure P is in direct porportion to the fourth power of acceleration a. This means light pressure causes the four dimensional spacetime accelerating expansion. This matches the current astrophysical observation.

When photon approaches the peripheral galaxy, it can keep on going along the curve of the universe. We can view universe as a expanding bubble. Thus, photon will go around a circle in the peripheral universe. If we let the period t=2pi*c/a=2pi*r/c=x/c, then we can re-write the Unruh effect as T*t=h'/k. That is the temepature-time equation formula. This means that temperature and time has inverse relation. In addition, we can also get a new rewritten Unruh effect as T*x=ch'/k. This means the temperature and distance also have inverse relation. Combining these two results, we can finally get a light pressure-spacetime relation P=(pi^2/60)h'/t*x^3.

During the beginning universe, the temerature is high and the light pressure P is also large. Thus, the acceleration a is large due to the high temperature. This is called the inflation period of universe. In our current universe, the background radiation temperature is only 2.73k, so the accelerating expansion of our current universe is much slower. However, we can still see the accelerating expansion. Based on the above equation, the acceleration will be slower and slower in the future.

The author's result is very exciting. In the book, the author also propose solutions of dark matter and grand unified theory inside this book. Most important of all, the author propose a new earthquake theory. This theory says that earthquake is actually an abrupt EM radiation release from crust fissure and hole. The EM radiation energy acting on crust causes earthquake. Thw author argue the current plate tectonic earthquake theory. First, plate movement is a very slow and continuous movement about 1cm per 30 years, and it can not explain the abrupt and huge power earthquake. Second, many huge intraplate earthquke such as Si-Chuan earthquake cannot be explained by the plate-tectonic theory. Third, the plate tectonic theory cannot explain the earthquake light, ionosphere anomaly, and other EM anomaly accompanying earthquake. By applying this new theory, we can successfully explain earthqake light and ionosphere anomaly during major earthquakes. It can also explain why EM anomaly is frequently observed during earthquake. If we can monitor the change of EM radiation, we might be able to predict earthquake.

The findings are very important. This book deserves more attention form the public and academic, especially for possible successful earthquake prediction.