New searches for supersymmetry presented by ATLAS experiment

The Standard Model is a remarkably successful but incomplete theory. Supersymmetry (SUSY) offers an elegant solution to the Standard Model's limitations, extending it to give each particle a heavy "superpartner" with different ...

Air pollution affects tree growth in Sao Paulo

As well as causing significant harm to human health, air pollution also stunts the growth of trees, one of the elements that can attenuate this typically urban environmental problem.

Could US wildfires be contributing to heart disease?

The destructive force of wildfires in the U.S. is well documented. Every year, on both the east and west coasts of the country, and due to both environmental and man-made factors, fires rage, and homes and habitats are destroyed. ...

Is dark matter made of axions? Black holes may reveal the answer

What is dark matter made of? It's one of the most perplexing questions of modern astronomy. We know that dark matter is out there, since we can see its obvious gravitational influence on everything from galaxies to the evolution ...

Elliptical galaxies shed new light on dark matter

In the 1930s, it was first noticed that the dynamics of astrophysical objects (galaxies, galaxy clusters and the universe itself) required an invisible and unknown form of mass, known now as dark matter. Strong mass discrepancies ...

Where there's waste there's fertilizer

We all know plants need nutrients, especially nitrogen and phosphorus. To give crops a boost, they are often put on fields as fertilizer. But we never talk about where the nutrients themselves come from.

Turning wastewater sludge into energy and mineral salts

A system developed by EPFL spin-off TreaTech can turn sludge from wastewater treatment plants into mineral salts – which could be used in fertilizer, for example – and biogas. The firm's research is being funded by several ...

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Matter is a general term for the substance of which all physical objects consist. Typically, matter includes atoms and other particles which have mass. A common way of defining matter is as anything that has mass and occupies volume. However, different fields use the term in different and sometimes incompatible ways; there is no single agreed scientific meaning of the word "matter".

For much of the history of the natural sciences people have contemplated the exact nature of matter. The idea that matter was built of discrete building blocks, the so-called particulate theory of matter, was first put forward by the Greek philosophers Leucippus (~490 BC) and Democritus (~470–380 BC). Over time an increasingly fine structure for matter was discovered: objects are made from molecules, molecules consist of atoms, which in turn consist of interacting subatomic particles like protons and electrons.

Matter is commonly said to exist in four states (or phases): solid, liquid, gas and plasma. However, advances in experimental techniques have realized other phases, previously only theoretical constructs, such as Bose–Einstein condensates and fermionic condensates. A focus on an elementary-particle view of matter also leads to new phases of matter, such as the quark–gluon plasma.

In physics and chemistry, matter exhibits both wave-like and particle-like properties, the so-called wave–particle duality.

In the realm of cosmology, extensions of the term matter are invoked to include dark matter and dark energy, concepts introduced to explain some odd phenomena of the observable universe, such as the galactic rotation curve. These exotic forms of "matter" do not refer to matter as "building blocks", but rather to currently poorly understood forms of mass and energy.

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