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PHVSICS OF THE IMPOSSIBLE
metrical quantities of matter and antimatter. So the lack of antimatter
is puzzling.
The most likely solution was first proposed by Andrei Sakharov,
the man who designed the hydrogen bomb for the Soviet Union in the
1950s. Sakharov theorized that at the beginning of the universe there
was a slight asymmetry in the amount of matter and antimatter in the
big bang. This tiny symmetry breaking is called "CP violation." This
phenomenon is currently the center of much vigorous research. In effect, Sakharov theorized that all the atoms in the universe today are left
over from a near perfect cancellation between matter and antimatter;
the big bang caused a cosmic cancellation between the two. The tiny
leftover matter created a residue that forms the visible universe of today. All the atoms in our bodies are leftovers from this titanic collision
of matter and antimatter.
This theory leaves open the possibility that small amounts of antimatter may occur naturally. If so, discovering that source would drastically reduce the cost of producing antimatter for use in antimatter
engines. In principle, deposits of naturally occurring antimatter should
be easy to detect. When an electron and an antielectron meet, they annihilate into gamma rays at an energy of 1.02 million electron volts or
more. Thus by scanning the universe for gamma rays at this energy,
one could find the "fingerprint" for naturally occurring antimatter.
In fact, "fountains" of antimatter have been found in the Milky Way
galaxy, not far from the galactic center, by Dr. William Purcell of
Northwestern University. Apparently a stream of antimatter exists that
creates this characteristic gamma radiation at 1.02 million electron
volts as it collides with ordinary hydrogen gas. If this plume of antimatter exists naturally, then it might be possible that other pockets of
antimatter exist in the universe that were not destroyed in the big bang.
To look for naturally occurring antimatter more systematically, the
PAMELA (Payload for Antimatter-Matter Exploration and Light-Nuclei
Astrophysics) satellite was launched into orbit in 2006. It is a collaborative effort between Russia, Italy, Germany, and Sweden, designed to
search for pockets of antimatter. Previous missions searching for antimatter were carried out using high-altitude balloons and the Space
PHVSICS OF THE IMPOSSIBLE
metrical quantities of matter and antimatter. So the lack of antimatter
is puzzling.
The most likely solution was first proposed by Andrei Sakharov,
the man who designed the hydrogen bomb for the Soviet Union in the
1950s. Sakharov theorized that at the beginning of the universe there
was a slight asymmetry in the amount of matter and antimatter in the
big bang. This tiny symmetry breaking is called "CP violation." This
phenomenon is currently the center of much vigorous research. In effect, Sakharov theorized that all the atoms in the universe today are left
over from a near perfect cancellation between matter and antimatter;
the big bang caused a cosmic cancellation between the two. The tiny
leftover matter created a residue that forms the visible universe of today. All the atoms in our bodies are leftovers from this titanic collision
of matter and antimatter.
This theory leaves open the possibility that small amounts of antimatter may occur naturally. If so, discovering that source would drastically reduce the cost of producing antimatter for use in antimatter
engines. In principle, deposits of naturally occurring antimatter should
be easy to detect. When an electron and an antielectron meet, they annihilate into gamma rays at an energy of 1.02 million electron volts or
more. Thus by scanning the universe for gamma rays at this energy,
one could find the "fingerprint" for naturally occurring antimatter.
In fact, "fountains" of antimatter have been found in the Milky Way
galaxy, not far from the galactic center, by Dr. William Purcell of
Northwestern University. Apparently a stream of antimatter exists that
creates this characteristic gamma radiation at 1.02 million electron
volts as it collides with ordinary hydrogen gas. If this plume of antimatter exists naturally, then it might be possible that other pockets of
antimatter exist in the universe that were not destroyed in the big bang.
To look for naturally occurring antimatter more systematically, the
PAMELA (Payload for Antimatter-Matter Exploration and Light-Nuclei
Astrophysics) satellite was launched into orbit in 2006. It is a collaborative effort between Russia, Italy, Germany, and Sweden, designed to
search for pockets of antimatter. Previous missions searching for antimatter were carried out using high-altitude balloons and the Space