Antimatter Surges Observed in the Universe


Scientists have seen surges in antimatter
particles sweeping through space, and some believe the cause could be
collapsing cosmic strings.  As opposed to Ming the Merciless.  Note
that cosmic strings are entirely different strings from string theory –
blame any confusion on the fact that there are far more cool things
happening in space than we have words for.

Cosmic strings are thought to come from from phase changes in space –
just as water freezing into ice may crack, cosmic strings are “cracks”
in gravitational fields.  Such strings would be thinner than a proton
but incredibly dense, just a couple of kilometers of such string would
have the same mass as Earth.

Cosmic string theory fell out of favor for a while, but a recent
resurgence has seen scientists hunting them in everything from galactic
double images to the cosmic wave background of the universe.  The most
awesome-sounding option is the positron surge observed last year by the
PAMELA (Payload for Antimatter Matter Exploration and Light-Nuclei
Astrophysics), an increased flux of antimatter-electrons sweeping
through space along with all the usual cosmic rays.

According to Professor Vachaspati of Case Western Reserve University,
these antimatter emissions could come from collapsing string segments.
Oscillations in the strings could cause loops of string to get “tied
off”, forming loops.  Such separated loops would collapse, releasing a
burst of positrons such as those detected by PAMELA.

It remains to be seen whether cosmic strings are truly back (and
blowing up!), but a whole host of missions – from the LISA
interferometry satellite network, to the South Pole IceCube neutrino
detector – will be searching for strings in the near future.

Posted by Luke McKinney.

Cosmic Strings Could Solve Positron Mystery


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