Hunting the Original Star Stuff

SDSU College of Sciences


SDSU astrophysicist Fridolin Weber will present his research on “Big Bang matter” at this year’s Albert W. Johnson lecture.


“It’s kind of mind-boggling. If things had happened just a little differently in the early universe, we wouldn’t be here.” Every atom in every molecule of your body was born in a single spectacular, 2000-billion-degree Kelvin explosion some 13.8 billion years ago. But the Big Bang also produced exotic forms of matter that lasted only fleeting seconds before blinking out of existence. Fridolin Weber searches the universe for these elusive particles that can only exist in extreme astronomical conditions, such as inside the hearts of super-dense neutron stars. The San Diego State University theoretical astrophysicist will present findings from his galactic hunt on Friday, April 7, at the annual Albert W. Johnson Lecture.Weber’s quarry is the quark, an elementary particle that constitutes matter’s most fundamental building block. Quarks are bound up in composite particles like protons and neutrons and are generally not found in nature by themselves. The exception is inside neutron stars, which are incredibly dense remnants of massive stars blown apart by supernova explosions. Composed primarily of neutrons, they are only 24 kilometers (15 miles) or so in diameter, yet are twice as massive as our sun. That amount of mass packed into a relatively miniscule area creates extraordinary density at the star’s core, squeezing atomic nuclei so tightly that fundamental particles like quarks can exist freely. It’s the closest parallel to conditions immediately after the Big Bang that we know of in our universe. “We want to understand what happened in the moments and minutes after that gigantic explosion,” Weber said. “We turn to neutron stars to see if we can detect the astrophysical signature of this ‘Big Bang matter.’”Weber and his colleagues trawl data from enormous radio telescopes scattered around the world. ...

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