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| Adam Riess |
Adam Riess is an astrophysicist born
in the U.S.A. known for his motivation driven research of supernovas. Riess won
the Shaw Prize in astronomy in 2006 and by 2001 he had won also the Nobel Prize
in physics along with his colleges for their reveal of an expanding
accelerating universe through supernovas.
The supernovas studied by Riess
where a type 1-A white dwarf which are powered by radioactive nuclear decay,
have ¼ the mass of the sun and are not stable (energy-wise). They used this
type of star because a supernova produces consistent peak luminosity given by the uniform mass that
explodes via the accretion mechanism. This value allows these explosions to be
used as like candles,process first discovered by Edwin Hubble, to measure the distance relatively to earth but can be used
for other galaxies because the visual
magnitude of the supernovae depends primarily on the distance. When
a white dwarf explodes it releases the brightest light it can emit and Hubble
helped discover the distance it was from the earth relative with the speed of
light. Later by conclusions from other scientist it was determined that if a
star is twice as faint, compared to the explosion, it is 4x farther that the
Hubble constant and if it is thrice as faint the supernova is actually 9x
farther. Thanks to Hubble, Riess can measure distances which can help him
determine whether the universe is expanding at a scaling speed.
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Timely evolution of the universe
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Riess
learned that the universe was expanding with acceleration by taking different
distances from different white dwarfs around the universe and comparing them
throughout different period of time and to other near galaxies, he got to the
conclusion because he found out that the planets where every time getting more distance
in between them, each time farther and farther thus the theory of the
accelerating expanding universe was born. Using this new found knowledge the
age of the universe changed, and it was not only because of the supernovas. The
age of the universe first became known using the Space Telescope to be from
10-11 billion years which was not taken seriously after a few years because a
scientist discovered a piece of rock that dated back to 13.5-14 billion years
which threw off the equation by around 3 billion years. Using the white dwarfs,
the same way Riess used it to measure an accelerating universe but in reverse,
there was found a more accurate result of 13.8 billion years to which the
scientific community took in as their new data. Riess almost did not get the
appreciation he deserved after all those years trying to decipher how the
universe was expanding because he knew he had another team of scientist,
working on the same thing, on his heels so when he got his conclusion he and
his colleges decided it was time to change the astrophysicist world by
publishing it before the other group. The other group had to publish it a year
later and it was found that they had almost the same conclusion but a small
detail was that Riess and his team found it faster.
I really
enjoyed this conference because it was entertaining and because I am fascinated
by space research, a little confession I envy anyone who get to travel and to
study space because they get to see what people on earth never get to see or
even do. There is not many thing known about the universe, the same as in earth with our oceans, but that is was
interest me the most, look a all the bizarre an amazing thing there are in
space and it is hypothesized to be only less than 1 % because every other thing
is either dark matter, dark energy or gas.
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