Changing shapes at the push of a button

Programmable materials are true shapeshifters. They can change their characteristics in a controlled and reversible way with the push of a button, independently adapting to fit new conditions. They can be used, for example, ...

Electronics & Semiconductors

25-nm iPMA Hexa-MTJ technology for scalable eFlash type STT-MRAM

A research group has announced a new iPMA-type Hexa-technology in Magnetic Tunnel Junctions (MTJ) that unlocks the door to improving ultra-low power in IoT edge-devices, mobile, automotive, consumer electronics, and applications ...


Inexpensive airborne testbeds could study hypersonic technologies

Miniature satellites known as CubeSats are taking on larger roles in space missions that might previously have been carried out by more expensive conventional spacecraft. Now, researchers at the Georgia Institute of Technology ...

Energy & Green Tech

The days of the hydrogen car are already over

Hydrogen fuel cell cars emerged as an alternative to both the electric and combustion engine vehicle in the early 2000s. They were widely considered an avenue towards universal green motoring. Powered through a chemical reaction ...

Electronics & Semiconductors

Miniature and durable spectrometer for wearable applications

Researchers have developed a wafer-thin chip-scale spectrometer that is suitable for wearable applications. The robust gallium nitride lab-on-a-chip device can also withstand harsh environments with severe radiation, such ...

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Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of the boundless four-dimensional continuum known as spacetime. In mathematics spaces with different numbers of dimensions and with different underlying structures can be examined. The concept of space is considered to be of fundamental importance to an understanding of the universe although disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework.

Many of the philosophical questions arose in the 17th century, during the early development of classical mechanics. In Isaac Newton's view, space was absolute - in the sense that it existed permanently and independently of whether there were any matter in the space. Other natural philosophers, notably Gottfried Leibniz, thought instead that space was a collection of relations between objects, given by their distance and direction from one another. In the 18th century, Immanuel Kant described space and time as elements of a systematic framework which humans use to structure their experience.

In the 19th and 20th centuries mathematicians began to examine non-Euclidean geometries, in which space can be said to be curved, rather than flat. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean space provides a better model for explaining the existing laws of mechanics and optics.

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