Engineering

Portable generator powers small safety devices

A new stick-like, water-based device can convert energy from movement into electricity. The technology, which was reported in the journal Science and Technology of Advanced Materials, could be used to power portable devices, ...

Engineering

Using 3D printing for alloy materials innovation

While millions of people around the world enjoy renewed mobility from hip and knee replacements, many don't realize that the materials used in such implants have basically stayed the same since the 1960s.

Computer Sciences

Neural network analyzes gravitational waves in real time

Black holes are one of the greatest mysteries of the universe—for example, a black hole with the mass of our sun has a radius of only 3 kilometers. Black holes in orbit around each other emit gravitational radiation—oscillations ...

Energy & Green Tech

Scientists bring efficiency to expanding offshore wind energy

New Cornell research shows how to make offshore wind farms more efficient in the face of impending rapid expansion—crucial information as the U.S. Department of the Interior affirmed White House plans to lease federal waters ...

Security

UN urges moratorium on use of AI that imperils human rights

The U.N. human rights chief is calling for a moratorium on the use of artificial intelligence technology that poses a serious risk to human rights, including face-scanning systems that track people in public spaces.

Robotics

Studies show promise using drones to elicit emotional responses

As drones become more ubiquitous in public spaces, researchers at Ben-Gurion University of the Negev (BGU) have conducted the first studies examining how people respond to various emotional facial expressions depicted on ...

Computer Sciences

Improving the way videos are organized

At any given moment, many thousands of new videos are being posted to sites like YouTube, TikTok, and Instagram. An increasing number of those videos are being recorded and streamed live. But tech and media companies still ...

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Space

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.

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