All Articles Tagged As: time

Erasing history? Temporal cloaks adjust light's throttle to hide an event in time (10/17/2011)

Moti Fridman and his colleagues Cornell University have demonstrated for the first time that it's possible to cloak a singular event in time, by sending a beam of light down an optical fiber and through a pair of "time lenses", creating a burst of light. They were able to create a small gap in the flow of light concealing that a burst of light ever occurred. The team will present their findings at FiO 2011. ...> Full Article

The atomic clock with the world's best long-term accuracy is revealed after evaluation (8/31/2011)

A clock in the UK is the most accurate long-term timekeeper in the world, reveals a study by an international science team. ...> Full Article

Why 'event cloaks' could be the key to the ultimate bank heist (7/8/2011)

In this month's special issue of Physics World, which examines the science and applications of invisibility, Martin McCall and Paul Kinsler of Imperial College London describe a new type of invisibility cloak that does not just hide objects -- but events. ...> Full Article

Large Hadron Collider could be world's first time machine (3/18/2011)

If the latest theory of Tom Weiler and Chui Man Ho is right, the Large Hadron Collider -- the world's largest atom smasher that started regular operation last year -- could be the first machine capable causing matter to travel backwards in time. ...> Full Article

Children use space to think about time (4/2/2010)

Space and time are intertwined in our thoughts, as they are in the physical world. For centuries, philosophers have debated exactly how these dimensions are related in the human mind. According to a paper to appear in the April 2010 issue of Cognitive Science, children's ability to understand time is inseparable from their understanding of space. ...> Full Article

Second 'quantum logic clock' based on aluminum ion is now world's most precise clock (2/7/2010)

Physicists at the National Institute of Standards and Technology have built an enhanced version of an experimental atomic clock based on a single aluminum atom that is now the world's most precise clock, more than twice as precise as the previous pacesetter based on a mercury atom. The new aluminum clock would neither gain nor lose one second in about 3.7 billion years, according to measurements to be reported in Physical Review Letters. ...> Full Article

From now on, 4 PTB primary atomic clocks will contribute to UTC (12/27/2009)

The new caesium fountain clock CSF2 is admitted into the exclusive international club of primary clocks. ...> Full Article

Optical atomic clock becomes portable (9/8/2009)

Optical clocks might become more compact and even portable, maybe in the future even travel to space. Scientists of the Physikalisch-Technische Bundesanstalt have shown how some fundamental difficulties, which a more simple set-up had previously hindered, could be avoided (see current edition of "Physical Review Letters"). In the next step they want to build such a clock. This clock could help to determine geographical heights more exactly than before. ...> Full Article

Ytterbium gains ground in quest for next-generation atomic clocks (8/17/2009)

NIST physicists have improved an experimental atomic clock based on ytterbium atoms, which now about four times more accurate than it was several years ago, giving it a precision comparable to that of the NIST-F1 cesium fountain clock. ...> Full Article

Ytterbium's broken symmetry (7/24/2009)

The largest parity violations ever measured in an atom ...> Full Article

Testing relativity in the laboratory (7/22/2009)

Xiang Zhang, a faculty scientist with the US Department of Energy's Lawrence Berkeley National Laboratory and professor at the University of California Berkeley, lead a study in which it was determined that the interactions of light and matter with spacetime, as predicted by general relativity, can be studied using the new breed of artificial optical materials that feature extraordinary abilities to bend light and other forms of electromagnetic radiation. ...> Full Article

Goal: developing the best atomic clock in the world (6/3/2009)

They are masters at working with light: the scientists at the newly founded QUEST Institute at the Physikalisch-Technische Bundesanstalt, Braunschweig. And they want to work on some of the most exciting questions relating to physics today: on unimaginably precise methods of measurement for observing the Earth, on the pressing question of the fundamentals of physics, of whether the fundamental constants are really constant, and on the development of the best atomic clock in the world made of a single aluminium atom. ...> Full Article

A step closer to an ultra precise atomic clock (4/17/2009)

A clock that is so precise that it loses only a second every 300 million years -- this is the result of new research in ultra cold atoms. The international collaboration is comprised of researchers from the University of Colorado and the Niels Bohr Institute at the University of Copenhagen and the results have just been published in the prestigious scientific journal Science. ...> Full Article

Atomic fountain clocks are becoming still more stable (3/19/2009)

They are at present the most accurate clocks in the world: caesium fountain clocks furnish the second accurate to 15 places after the decimal point. Until they reach this accuracy, caesium fountain clocks, however, need a certain measurement time. This time has now been considerably reduced with the aid of a new method developed at the Physikalisch-Technische Bundesanstalt which makes the output frequency of the caesium fountains more stable. ...> Full Article

Gift will allow scientists to continue simulating warped space-time (3/12/2009)

The Sherman Fairchild Foundation has awarded $3.1 million to the California Institute of Technology (Caltech) to support the Caltech-Cornell Program for Simulation of eXtreme Spacetimes (SXS) through 2013. ...> Full Article

'Quantum logic clock' rivals mercury ion as world's most accurate clock (3/9/2008)

Comparison yields best results yet in tests for change in 'constants' of nature ...> Full Article

New Experimental Atomic Clock Surpasses Accuracy Of Current U.S. Standard Time Clock (2/15/2008)

A next-generation atomic clock developed by researchers from the National Institute of Standards and Technology and the University of Colorado at Boulder has been shown to be accurate to within one second over 200 million years, surpassing the accuracy of the current U.S. time standard atomic clock more than two-fold. ...> Full Article

Researcher studies what makes quantum dots blink (10/2/2007)

In order to learn more about the origins of quantum dot blinking researchers have developed a method to characterize it on faster time scales than have previously been accessed. ...> Full Article