|
THE UNIFICATION OF the fundamental forces into one theory is
of great interest to physicists. To date, the Standard Model, which incorporates
the weak and electromagnetic interactions, has withstood experimental tests.
However, the strong interaction and gravity have yet to be
included successfully. Many competing unified theories have been devised.
These theories can be tested by looking at the properties of elementary
particle interactions. However, many effects of the interactions have not
been discovered or observed due to the smallness of the effects and
the restricted precision of experimental techniques.
In our research we looked at the breaking of fundamental symmetries
in the radium atom. Using analytical and numerical methods, we
made predictions for the effects of violations of the symmetries of space and time.
A finite atomic electric dipole moment (EDM) necessitates the existence
of time invariance violation. From our calculations we found that radium
has an induced atomic EDM which exceeds that of all other atoms considered so
far by as much as 105. Time invariance violation has never been
directly observed. The huge enhancement of the EDM in radium may provide the
first unambiguous detection of time
invariance violation when studied experimentally, or will at least give
an improved upper limit on the value of time invariance violating effects.
|
The competing unified theories make very different predictions for
the induced EDM. This means that experimental studies with radium
could reduce the number of these models and help find a correct description
of elementary particle interactions.
It is also very important to study parity violating effects, as these also provide
a window to physics beyond the Standard Model. We showed that in radium
there is a huge enhancement of certain parity violating effects which exceed
those studied experimentally by as much as 103.
So we can see that radium is an excellent candidate for
experimental work on parity and time invariance violation. This potential
breakthrough in the sensitivity of parity and time invariance violating effects
has interested experimentalists from Los Alamos, Princeton, the University
of Michigan, and the University of Washington, who are considering
the possibilities of performing experiments on radium.
Vladimir
Dzuba,
Victor Flambaum &
Jacinda Ginges |
