The international collaborators of the ALPHA- 2 experiment have
measured the charge of antihydrogen to be zero with the greatest
precision yet, narrowing the possibilities of where a difference between
hydrogen and its antimatter counterpart could be found.
Francis Robicheaux, a professor of physics at Purdue University, is
part of the international team of ALPHA scientists performing a series
of experiments at the European Organization for Nuclear Research, or
CERN, in Geneva, Switzerland.
“It is thought that matter and antimatter appeared in equal amounts
after the Big Bang, but the Standard Model of particle physics offers no
explanation for why antimatter is absent in the observable universe,” he
says. “We are pursuing a better understanding of antimatter and
testing the Standard Model to see where a change may be necessary.”
It is theorized that antimatter is made up of particles, called
antiparticles, that are identical to ordinary matter particles, but with an
opposite charge. Whereas a hydrogen atom is made up of a positively
charged proton and negatively charged electron, an antihydrogen atom
is made up of a negatively charged antiproton and a positively charged
positron. However, it is thought that at some point there is another
difference that breaks the symmetry between matter and antimatter.
“If we find an asymmetry between matter and antimatter, it would
provide tremendous insight into the fundamental physics of our
universe,” says Robicheaux. “One difference could be that antihydrogen
has a net charge, but it would be a very subtle difference, barely above
zero, that could only be seen through extremely precise measurements.
We must look very carefully to either discover the charge or effectively
rule it out as the point of asymmetry.”
The scientists use CERN’s antiproton decelerator to study the
trajectories of antihydrogen atoms released in the presence of an
electric field. If the antihydrogen atoms had an electric charge, the
electric field would deflect them and alter their trajectories.
“We showed that the charge of the antihydrogen would have to be
more than a billion times smaller than the charge of an electron to
survive,” Robicheaux says. “Even though the charge measurement gave
the expected result, we’re motivated by the possibility of being
surprised. There are a lot of possible measurements we can do and it
would be momentous if one of them disagreed with current theories.”
— Elizabeth K. Gardner
remains neutral in ALPHA experiments
Trajectories of antihydrogen atoms from the ALPHA experiment.
(Photo courtesy of Chukman So/University of California, Berkeley)
The Department of Computer Science
will offer a new degree concentration in
information security starting with
courses in summer 2016.
The program will allow anyone with a
computing or programming background
to obtain a Master of Computer Science
degree in one year. Unlike a traditional
master’s degree, this program is open to
professionals whose undergraduate
degree may not have been in computer
science. The program is appropriate for
professionals with programming
experience acquired during their
professional career, those who earned a
computer science minor as an
undergraduate, or recent
undergraduates with a computing major.
Students will earn the degree with 30
credit hours, including two gateway
courses, six computer science courses
CONCENTRATION TO BE OFFERED
and two electives. Students are
anticipated to graduate in 12 months.
The first group of students will be
admitted into the program in the
summer with the gateway course
sequence starting in the June summer
session. The gateway sequence courses
will offer students a refresher so that
they are better prepared to succeed in
the remainder of the courses.
Randy Bond, assistant head of the
Department of Computer Science, says
the concentration will provide students
with the skills to implement security
features on traditional computer
systems and networks, plus a variety of
devices, including mobile phones,
airplanes, cars and point-of-sale
— Megan Huckaby