The latency advantage of microwave over fiber is a physical constant
, varying only by the length of the route.
No one knows why, but scientists say the kilogram's current definition--"a unit of mass equal to the mass of the international prototype of the kilogram"--no longer works; they're trying to develop one that's based on a physical constant
rather than an object whose weight can change.
Let us initially simplify matters greatly by assuming that we have only one physical constant
to explain--call it [lambda]--which we shall assume takes on an improbable value in our universe.
used in the determination of the airkerma rate Physical constant
Value Relative standard uncertainty (%) [[rho].
One theory proposed to explain this coincidence is assuming the existence of an infinite number of universes, each with their own physical constant
Now, scientists hope to define the kilogram by referring to a physical constant
rather than an antique object.
and the Gurzadyan-Xue formula for the dark energy.
In the June 20 NATURE, Schlesinger and Tom Wigley at the University of East Anglia in Norwich, England, demonstrated analytically that the lag time between increased greenhouse-gas levels and warmer temperatures is not a fixed, physical constant
, as many past CO.
The value of any physical constant
can be obtained in the following way.
This is achieved by an internal on-line wavelength calibrator which is based on a physical constant
reference, guaranteeing the highest wavelength accuracy over instrument lifetime without recalibration.
Scientists aim to give the kilogram a new definition based on nature's fundamental physical constants
Each chapter includes recommended further reading in addition to the reference list, and appendices summarize notation and conventions, observables and Feynman rules, and physical constants