News tagged with electromagnetic radiation

Variations in fine-structure constant suggest laws of physics not the same everywhere

(PhysOrg.com) -- One of the most controversial questions in cosmology is why the fundamental constants of nature seem fine-tuned for life. One of these fundamental constants is the fine-structure constant, ...

Physics / General Physics

created Sep 06, 2010 | popularity 4.9 / 5 (78) | comments 77 | with audio podcast report

Gamma-ray photon race ends in dead heat; Einstein wins this round

Racing across the universe for the last 7.3 billion years, two gamma-ray photons arrived at NASA's orbiting Fermi Gamma-ray Space Telescope within nine-tenths of a second of one another. The dead-heat finish ...

Physics / General Physics

created Oct 28, 2009 | popularity 4.6 / 5 (37) | comments 62

A Theory of Dark Matter

Among the most astounding, unexpected, and important achievements of the past century (or even more) have been the discoveries of dark matter and dark energy, collectively dubbed the "dark sector."

Physics / General Physics

created Sep 08, 2009 | popularity 3.6 / 5 (45) | comments 58

'Necropanspermia' suggested as a way of seeding life on Earth

(PhysOrg.com) -- Panspermia is a mechanism for spreading organic material throughout the galaxy, but the destructive effects of cosmic rays and ultraviolet light tend to mean most organisms would be destroyed ...

Space & Earth / Space Exploration

created Nov 12, 2010 | popularity 3.8 / 5 (32) | comments 47 | with audio podcast report

Scientists turn light into electrical current using a golden nanoscale system

Material scientists at the Nano/Bio Interface Center of the University of Pennsylvania have demonstrated the transduction of optical radiation to electrical current in a molecular circuit. The system, an array ...

Nanotechnology / Nanophysics

created Feb 12, 2010 | popularity 4.9 / 5 (21) | comments 3 | with audio podcast

Turning metal black more than just a novelty

(PhysOrg.com) -- University of Rochester optics professor Chunlei Guo made headlines in the past couple of years when he changed the color of everyday metals by scouring their surfaces with precise, high-intensity laser bursts.

Physics / General Physics

created Dec 08, 2009 | popularity 4.6 / 5 (20) | comments 5

Astronomers reveal a cosmic 'axis of evil'

(PhysOrg.com) -- Astronomers are puzzled by the announcement that the masses of the largest objects in the Universe appear to depend on which method is used to weigh them. The new work was presented at a specialist ...

Space & Earth / Astronomy

created Jun 30, 2011 | popularity 4.8 / 5 (17) | comments 23 | with audio podcast

Probing the dark side of the universe

Advancing into the next frontier in astrophysics and cosmology depends on our ability to detect the presence of a particular type of wave in space, a primordial gravitational wave. Much like ripples moving ...

Physics / General Physics

created May 20, 2010 | popularity 4.6 / 5 (15) | comments 99 | with audio podcast

Testing relativity in the lab

Even Albert Einstein might have been impressed. His theory of general relativity, which describes how the gravity of a massive object, such as a star, can curve space and time, has been successfully used to ...

Physics / General Physics

created Jul 20, 2009 | popularity 4.7 / 5 (14) | comments 25

Fermi Telescope Caps First Year With Glimpse of Space-Time (w/ Video)

During its first year of operations, NASA's Fermi Gamma Ray Space Telescope mapped the extreme sky with unprecedented resolution and sensitivity. It captured more than one thousand discrete sources of gamma ...

Space & Earth / Astronomy

created Oct 28, 2009 | popularity 4.6 / 5 (14) | comments 5

Scientists create artificial mini 'black hole'

(PhysOrg.com) -- Scientists from China have built a device that can trap and absorb microwaves coming from all directions with a 99% absorption rate - a property that makes the device simulate, to some extent, ...

Physics / General Physics

created Jun 03, 2010 | popularity 3.9 / 5 (16) | comments 13 | with audio podcast report

Study resolves century-long debate over how to describe electromagnetic momentum density in matter

(PhysOrg.com) -- Researchers from the NIST Center for Nanoscale Science and Technology and the University of British Columbia have shown that the interaction between a light pulse and a light-absorbing object, including the ...

Physics / General Physics

created Dec 29, 2011 | popularity 4.4 / 5 (14) | comments 23 | with audio podcast

Very High Energy Gamma Rays

(PhysOrg.com) -- Gamma-rays are the most energetic known form of electromagnetic radiation, with each gamma ray being at least one hundred thousand times more energetic than an optical light photon. The most ...

Space & Earth / Astronomy

created Sep 25, 2009 | popularity 4.6 / 5 (13) | comments 3

New 'metamaterial' device may lead to see-through cameras and scanners

Devices that can mimic Superman's X-ray vision and see through clothing, walls or human flesh are the stuff of comic book fantasy, but a group of scientists at Boston University (BU) has taken a step toward making such futuristic ...

Physics / Optics & Photonics

created May 06, 2010 | popularity 4.9 / 5 (12) | comments 1 | with audio podcast

First acoustic metamaterial 'superlens' created

A team of researchers at the University of Illinois has created the world's first acoustic "superlens," an innovation that could have practical implications for high-resolution ultrasound imaging, non-destructive ...

Physics / General Physics

created Jun 24, 2009 | popularity 4.4 / 5 (13) | comments 6

Electromagnetic radiation

Electromagnetic radiation (sometimes abbreviated EMR) is a ubiquitous phenomenon that takes the form of self-propagating waves in a vacuum or in matter. It consists of electric and magnetic field components which oscillate in phase perpendicular to each other and perpendicular to the direction of energy propagation. Electromagnetic radiation is classified into several types according to the frequency of its wave; these types include (in order of increasing frequency and decreasing wavelength): radio waves, microwaves, terahertz radiation, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays. A small and somewhat variable window of frequencies is sensed by the eyes of various organisms; this is what we call the visible spectrum, or light.

EM radiation carries energy and momentum that may be imparted to matter with which it interacts.

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