Frontpage » Tag » quantum

News tagged with quantum

Physicists build highly efficient 'no-waste' laser

A team of University of California, San Diego researchers has built the smallest room-temperature nanolaser to date, as well as an even more startling device: a highly efficient, "thresholdless" laser that ...

Physics / General Physics

created Feb 08, 2012 | popularity 4.9 / 5 (20) | comments 5 | with audio podcast

Flipping a light switch in the cell: Quantum dots used for targeted neural activation

By harnessing quantum dots—tiny light-emitting semiconductor particles a few billionths of a meter across—researchers at the University of Washington (UW) have developed a new and vastly more targeted ...

Physics / Optics & Photonics

created Feb 08, 2012 | popularity 5 / 5 (7) | comments 1 | with audio podcast

Quantum physicist explains $100K offer for proof scaled-up quantum computing is impossible

(PhysOrg.com) -- MIT researcher Scott Aaronson has certainly riled the physics community with his offer this past Friday, of $100,000 to anyone who can prove that scaled-up quantum computing is impossible. ...

Physics / Quantum Physics

created Feb 08, 2012 | popularity 4.2 / 5 (13) | comments 33 | with audio podcast weblog

Quantum microphone captures extremely weak sound

(PhysOrg.com) -- Scientists from Chalmers have demonstrated a new kind of detector for sound at the level of quietness of quantum mechanics. The result offers prospects of a new class of quantum hybrid circuits ...

Physics / Quantum Physics

created Feb 06, 2012 | popularity 5 / 5 (1) | comments 2

A quantum connection between light and motion

(PhysOrg.com) -- Physicists have demonstrated a system in which light is used to control the motion of an object that is large enough to be seen with the naked eye at the level where quantum mechanics governs ...

Physics / Quantum Physics

created Feb 06, 2012 | popularity 4.9 / 5 (22) | comments 6 | with audio podcast

Searching for a solid that flows like a liquid

(PhysOrg.com) -- A series of neutron scattering experiments at Oak Ridge National Laboratory and other research centers is exploring the key question about a long-sought quantum state of matter called supersolidity: ...

Physics / Quantum Physics

created Feb 03, 2012 | popularity 4.3 / 5 (7) | comments 16 | with audio podcast

Repulsive gravity as an alternative to dark energy (Part 2: In the quantum vacuum)

(PhysOrg.com) -- During the past few years, CERN physicist Dragan Hajdukovic has been investigating what he thinks may be a widely overlooked part of the cosmos: the quantum vacuum. He suggests that the quantum vacuum has ...

Physics / General Physics

created Feb 01, 2012 | popularity 4.8 / 5 (72) | comments 143 | with audio podcast report

Bright lights of purity: Researchers discover why pure quantum dots and nanorods shine brighter

To the lengthy list of serendipitous discoveries – gravity, penicillin, the New World – add this: Scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered why a promising ...

Nanotechnology / Nanomaterials

created Jan 30, 2012 | popularity 5 / 5 (8) | comments 1 | with audio podcast

Nanotube-based terahertz polarizer nears perfection

(PhysOrg.com) -- Researchers at Rice University are using carbon nanotubes as the critical component of a robust terahertz polarizer that could accelerate the development of new security and communication ...

Nanotechnology / Nanophysics

created Jan 30, 2012 | popularity 4.7 / 5 (10) | comments 1 | with audio podcast

Many bodies make one coherent burst of light: Researchers see superfluorescence from solid-state material

In a flash, the world changed for Tim Noe – and for physicists who study what they call many-body problems. The Rice University graduate student was the first to see, in the summer of 2010, proof of a ...

Physics / General Physics

created Jan 30, 2012 | popularity 4.8 / 5 (4) | comments 5 | with audio podcast

Quantum physicists shed new light on relation between entanglement and nonlocality

(PhysOrg.com) -- New research from the University of Bristol may disprove a long-standing conjecture made by one of the founders of quantum information science: that quantum states featuring ‘positive partial transpose’, ...

Physics / Quantum Physics

created Jan 30, 2012 | popularity 4.6 / 5 (24) | comments 35 | with audio podcast

Speed limit on the quantum highway

(PhysOrg.com) -- Physicists at the Max Planck Institute of Quantum Optics have measured the propagation velocity of quantum signals in a many-body system.

Physics / Quantum Physics

created Jan 26, 2012 | popularity 4.9 / 5 (15) | comments 0 | with audio podcast

JQI cool nano loudspeakers could makes for better MRIs, quantum computers

(PhysOrg.com) -- A team of physicists from the Joint Quantum Institute (JQI), the Neils Bohr Institute in Copenhagen, Denmark, and Harvard University has developed a theory describing how to both detect weak ...

Physics / Quantum Physics

created Jan 25, 2012 | popularity 4.8 / 5 (4) | comments 0 | with audio podcast

Study supports role of quantum effects in photosynthesis

(PhysOrg.com) -- Until a few years ago, photosynthesis seemed to be a straightforward and well-understood process in which plants and other organisms use sunlight to convert carbon dioxide and water into sugars, ...

Physics / General Physics

created Jan 25, 2012 | popularity 4.9 / 5 (13) | comments 7 | with audio podcast feature

Rice lab mimics Jupiter's Trojan asteroids inside a single atom

Rice University physicists have gone to extremes to prove that Isaac Newton's classical laws of motion can apply in the atomic world: They've built an accurate model of part of the solar system inside a single ...

Physics / Quantum Physics

created Jan 24, 2012 | popularity 4.5 / 5 (13) | comments 6 | with audio podcast

Quantum

In physics, a quantum (plural: quanta) is an indivisible entity of a quantity that has the same units as the Planck constant and is related to both energy and momentum of elementary particles of matter (called fermions) and of photons and other bosons. The word comes from the Latin "quantus", for "how much." Behind this, one finds the fundamental notion that a physical property may be "quantized", referred to as "quantization". This means that the magnitude can take on only certain discrete numerical values, rather than any value, at least within a range. There is a related term of quantum number.

A photon is often referred to as a "light quantum". The energy of an electron bound to an atom (at rest) is said to be quantized, which results in the stability of atoms, and of matter in general. But these terms can be a little misleading, because what is quantized is this Planck's constant quantity whose units can be viewed as either energy multiplied by time or momentum multiplied by distance.

Usually referred to as quantum "mechanics", it is regarded by virtually every professional physicist as the most fundamental framework we have for understanding and describing nature at the infinitesimal level, for the very practical reason that it works. It is "in the nature of things", not a more or less arbitrary human preference.

For more information about Quantum, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.