Written in the stars
“Some say the world will end in fire, some say in ice…” *
What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.
In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.
The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.
The teams used a particular kind of supernova, called type Ia supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.
For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.
The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.
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An amazing discovery was made by the 2011 Nobel Prize winner in Physics. During an effort to measure the rate at which the expansion of the universe (caused by the Big Bang), scientists were shocked to discover that the rate of expansion is actually increasing. Scientists are baffled. Some postulate that energy from dark matter is the force causing the increase.
I think God is smiling as he watches us scratch our heads. How can the rate of expansion resulting from one cosmic explosion (Big Bang) be getting faster? Our current understanding of Physics tells us it should be slowing down. Common sense tells us the same. I love it when science reveals another mystery about our universe that supports, not contradicts, belief in God.
KEY DATES IN THE CONVICTION OF AMANDA KNOX
Nov 2, 2007: Body of Meredith Kercher is found in Perugia apartment. Investigators say she was killed the night before.
Nov 6, 2007: Knox is arrested with then-boyfriend Raffaele Sollecito, and Diya ‘Patrick’ Lumumba, Congolese owner of pub where Knox occasionally worked.
Nov 20, 2007: Lumumba, implicated by Knox statements to police, is released from jail for lack of evidence.
Dec 6, 2007: Ivory Coast national Rudy Hermann Guede is extradited from Germany, where he was arrested, and jailed upon arrival in Italy.
Dec 14, 2007: Meredith is laid to rest after funeral in London.
Oct 28, 2008: Judge indicts Knox and Sollecito on murder and sexual assault charges. Guede, who was granted a fast-track trial, is convicted of murder and sexual assault and sentenced to 30 years in prison.
Jan 16, 2009: Trial of Knox and Sollecito opens in Perugia.
Jun 12, 2009: Knox takes stand; tells court she was shocked by Meredith’s death, offers alibi and says police beat her into making false statements.
Dec 4, 2009: Court finds Knox guilty of murder and sexual assault; sentences her to 26 years in prison. Sollecito is convicted of same charges and sentenced to 25 years.
Dec 22, 2009: Appeals court upholds Guede conviction and cuts sentence to 16 years.
Nov 8, 2010: Judge orders Knox to stand trial on slander charges for claiming police beating.
Nov 24, 2010: Appeals trial for Knox and Sollecito opens in Perugia.
Dec 16, 2010: Italy’s highest criminal court upholds Guede’s conviction and 16-year prison sentence.
June 29, 2011: Independent forensic report ordered by appeals court finds much of the DNA evidence used to convict Knox and Sollecito is unreliable.
October 3, 2011: Knox and Sollecito are freed after appeals court overturns conviction for murder.
Good timeline of Kercher murder and Knox 4-year drama. I followed this story the whole time and thought that she was innocent at the beginning. It just didn’t add up. So when the verdict to overturn her conviction was reached today, I was watching it live and was actually holding my breath. I’m very glad for the outcome. Welcome home Amanda.
Over the course of the appeals trial, the defendants’ positions have significantly improved, mainly because a court-ordered independent review cast serious doubts over the main DNA evidence linking the two to the crime.
Prosecutors maintain that Knox’s DNA was found on the handle of a kitchen knife believed to be the murder weapon, and that Kercher’s DNA was found on the blade. They said Sollecito’s DNA was on the clasp of Kercher’s bra as part of a mix of evidence that also included the victim’s genetic profile.
But the independent review — ordered at the request of the defense, which had always disputed those findings — reached a different conclusion.
The two experts found that police conducting the investigation had made glaring errors in evidence-collecting and that below-standard testing and possible contamination raised doubts over the attribution of DNA traces, both on the blade and on the bra clasp, which was collected from the crime scene 46 days after the murder.
The review was crucial in the case because no motive has emerged and witness testimony was contradictory. It was a huge boost for the defense’s hope and a potentially fatal blow for the prosecution.
The prosecutors, however, refute the review and stand by their original conclusions.