My name is Lê and I believe that the greatest challenge in education is to make science and math appealing.
This is why I aim at bringing enthusiasm and excitement to the readers’ learning experience.
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Geometry and General RelativityGeometry and General Relativity By Scott McKinney | Updated:2015-12 | Views: 2835 From our “intrinsic” point-of-view on the surface of the Earth, it appears to be flat, but if we examine the Earth from the “extrinsic” point of view, somewhere off the Earth’s surface, we can see that it is clearly a curved surface. Amazingly, it is possible to determine that the Earth is spherical simply by taking measurements on its surface, and it is possible to generalize these measurements in order to study the shape of the universe. Mathematicians such as Riemann did just this, and Einstein was able to apply these geometric ideas to his “general theory of relativity”, which describes the relation between gravitation, space, and time.

Optimization by Linear ProgrammingOptimization by Linear Programming By Lê Nguyên Hoang | Updated:2016-02 | Views: 6881 Operations Research deals with optimizing industrial systems. Those systems can be very complex and their modeling may require the use of hundreds, thousands or even millions of variables. Optimizing over millions of variables may seem impossible, but it can be done if the optimization problem has a linear structure. Learn more on this linear structure and optimization solutions!

P versus NP: A Crucial Open ProblemP versus NP: A Crucial Open Problem By Lê Nguyên Hoang | Updated:2016-01 | Views: 6315 P=NP is probably today’s most crucial open problem. Not only is it a very theoretical question in computer science and mathematics, but it also has major implications to real world. Its resolution could revolutionize the world. This article gives the definition and major results of P=NP.

The Secretary/Toilet Problem and Online OptimizationThe Secretary/Toilet Problem and Online Optimization By Lê Nguyên Hoang | Updated:2015-12 | Views: 3375 A large chunk of applied mathematics has focused on optimizing something with respect to all relevant data. However, in practice, especially in the online world, the data is not available to us, and, yet, we’re still expected to make nearly optimal decisions. This problem is exemplified by the famous secretary problem, where a manager needs to decide to hire candidates right after interviews, even though he has not yet met all the candidates. In this article, we review this classic as well as many very recent developments.

The Limitless Vertigo of Cantor’s InfiniteThe Limitless Vertigo of Cantor’s Infinite By Lê Nguyên Hoang | Updated:2015-12 | Views: 2937 No one believed him. Not even fellow mathematicians. They thought he was wrong. They thought he was crazy. Even he ended up doubting himself and went crazy. And yet, he had mathematically proved it all. Georg Cantor had figured out how to manipulate the infinite. Even more remarkable, he showed that there were actually several infinities; and some are bigger than others!

Darwin’s Theory of EvolutionDarwin’s Theory of Evolution By Lê Nguyên Hoang | Updated:2016-01 | Views: 13869 Darwin’s theory of evolution is one of the greatest of all time. It’s also one of the most controversial. This article presents the most fundamental concepts of the theory. We’ll also provide results of modern science and discuss to which extend to they confirm Darwin’s postulates.

Multicriteria with MACBETHMulticriteria with MACBETH By Lê Nguyên Hoang | Updated:2016-02 | Views: 2586 As more and more complex problems are dealt with in our societies, developing models such as multi-criteria analysis is crucial to better understand these problems. MACBETH is a state-of-the-art method to do just that. Its functioning is described in this article.

Marriage Assignment Problem and VariantsMarriage Assignment Problem and Variants By Lê Nguyên Hoang | Updated:2016-02 | Views: 5530 Marriage problems consist in matching boys and girls. They are a very interesting class of problems that include assignment problems, which have a very large range of applications. Additional results have been found for variants which include the introduction of boys and girls’ preferences, and cases where people cannot be categorized into two groups.