Electronics & Semiconductors

Making batteries live longer with ultrathin lithium

Our lives today are governed by electronics in all shapes and forms. Electronics, in turn, are governed by their batteries. However, the traditional lithium-ion batteries (LIBs), that are widely used in electronic devices, ...

Energy & Green Tech

Perovskite solar modules: High efficiency on a large surface area

From cell to module without loss of efficiency: This is one of the main challenges of perovskite photovoltaics. Researchers at Karlsruhe Institute of Technology (KIT) have now managed to produce perovskite solar modules with ...


Snakeskin can inspire safer buildings

Despite human inventiveness and ingenuity, we still lag far behind the elegant and efficient solutions forged by nature over millions of years of evolution.


Sunlight to solve the world's clean water crisis

Researchers at UniSA have developed a cost-effective technique that could deliver safe drinking water to millions of vulnerable people using cheap, sustainable materials and sunlight.


Researchers develop all-round grippers for contact-free society

The Korea Institute of Machinery and Materials (KIMM) successfully developed all-round gripper technology, enabling robots to hold objects of various shapes and stiffnesses. With the new technology, a single gripper can be ...

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In mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R3 — for example, the surface of a ball or bagel. On the other hand, there are surfaces which cannot be embedded in three-dimensional Euclidean space without introducing singularities or intersecting itself — these are the unorientable surfaces.

To say that a surface is "two-dimensional" means that, about each point, there is a coordinate patch on which a two-dimensional coordinate system is defined. For example, the surface of the Earth is (ideally) a two-dimensional sphere, and latitude and longitude provide coordinates on it — except at the International Date Line and the poles, where longitude is undefined. This example illustrates that not all surfaces admits a single coordinate patch. In general, multiple coordinate patches are needed to cover a surface.

Surfaces find application in physics, engineering, computer graphics, and many other disciplines, primarily when they represent the surfaces of physical objects. For example, in analyzing the aerodynamic properties of an airplane, the central consideration is the flow of air along its surface.

This text uses material from Wikipedia, licensed under CC BY-SA