Thinking and Computing

2 downloads 0 Views 20MB Size Report
into energy by combining 4 protons to make a He4 nucleus. (Hans Bethe Nobel Prize 1967) p + e→n + ν proton and electron become neutron and neutrino ...
Thinking and Computing A summary of the! 221st AAS Plenary Talk! Henry Norris Russell Lecture! ! W. David Arnett! Steward Observatory! University of Arizona! Tucson AZ

It is a great honor for me to be named the

Henry Norris Russell Lecturer

of the American Astronomical Society for 2012,

for lifetime achievements in astrophysics My goal tonight is to explain simply what I did,

and how it relates to physics and astronomy Instead of a telescope I used

computers and a lot of thinking

Some words

to know:

! supernova: a big nova

(“new star” in latin), explosion of a star; makes most of the chemical elements and often leaves a neutron star or black hole

! nucleosynthesis: making the nuclei (of atoms)

! matter: the visible matter is made mostly of electrons, neutrons and protons (which are combined to form stars, planets and people)



big bang: the origin of the known universe about 13.5 billion years ago

1996

Inventor: Ole Kirk Christiansen, 1949, Denmark

Atoms and Nuclei are like Legos: they are building blocks

(Thanks to Ronan, Blake, Stephen, Delaney, Jennifer and Eric)

Another product

of Denmark

Niels Bohr

atomic theory

Cast of Prominent Characters Particle/wave

Mass

Charge

photon (light)

0

0

electron

0.511

-1

proton

938.27

+1

neutron

939.56

0

neutrinos