“‘As you go back in time, the universe is pushing [outward] less and less,’ he said. ‘At some point, the pressure of dark energy is zero and is exerting no force on the universe. There is no explanation for it.'” New cosmological research announced yesterday further muddles our understanding of the expansion of the early universe and (once again) casts doubt on Einstein’s recently resurrected cosmological constant. “Schaefer based his findings on analysis of ultra-bright cosmic explosions called gamma-ray bursts, detected as far as 12.8 billion light-years away. He found that the most distant explosions appeared brighter than they should have been if the universe were accelerating at a constant rate.“
Category: Physics
Destroyer of Worlds.
“We have discovered the most terrible bomb in the history of the world. It may be the fire destruction prophesied in the Euphrates Valley Era, after Noah and his fabulous Ark.” Have your perambulators and origami cranes at the ready…I missed this ten days ago amid the Half-Blood hullabaloo and drive south, but it’s very well-done: 20/20 Hindsight takes a trip in the Wayback Machine to blog the 60th anniversary of the Trinity Test in real-time.
No more paradoxes.
“‘Things aren’t getting better; they’re getting worse. The White House is completely disconnected from reality,’ said Hagel, a member of the Foreign Relations Committee. ‘It’s like they’re just making it up as they go along. The reality is that we’re losing in Iraq.’” Two quality links via the consistently splendid Follow Me Here: First, Republican Senators McCain and Hagel call out Dubya on the war. Between this and “Freedom Fries” Jones, are the floodgates opening in GOP-land?
And, on an altogether different note, physicists cast doubt on the possibility of time travel paradoxes “When Greenberger and Svozil analysed what happens when…component waves flow into the past, they found that the paradoxes implied by Einstein’s equations never arise. Waves that travel back in time interfere destructively, thus preventing anything from happening differently from that which has already taken place.” (Well, looks like time-traveling historians won’t need to worry about any Primeresque recursions, then.)
Opp-Ed.
“As a chapter in the continuing history of opposition to dissent, Oppenheimer‘s fate is especially worth re-exploring now. Whether in the closed halls of the intelligence services or in the open sessions of Congress, we need the hard impact of contestation; we need recalcitrant voices ready to challenge the established terms of discussion…Oppenheimer always thought that argued dissent was an inseparable part of patriotism. He was right.” In his review of the recent biography American Prometheus, Harvard’s Peter Galison lauds J. Robert Oppenheimer’s patriotic vision of reflective dissent.
In Search of M.
“String theory, the Italian physicist Dr. Daniele Amati once said, was a piece of 21st-century physics that had fallen by accident into the 20th century. And, so the joke went, would require 22nd-century mathematics to solve.” The New York Times surveys string theory at 20…fascinating stuff, but I still don’t get it.
Riddles in the Dark.
In celebration of a quarter-century of Science Times, the paper ruminates on the 25 questions currently driving science, while Alan Lightman ponders the motivations that fuel scientists. I’m not sure if the likes of Stephen Hawking are really contemplating Atlantis, but there’s some intriguing stuff here.
Space Cadet.
General Wesley Clark stumps for faster-than-light travel in New Hampshire. “I still believe in e=mc², but I can’t believe that in all of human history, we’ll never ever be able to go beyond the speed of light to reach where we want to go. I happen to believe that mankind can do it…It’s my only faith-based initiative.” Well, I guess he’s up on Dubya, who’s still trying to work out evolution. At the same rally, Clark introduced Professor John Frink as his potential National Science Advisor. “Suppose we extend the square beyond the two dimensions of our universe… along the hypothetical Z axis, there…”
Worth a Thousand Answers.
Big news and bold statements are issuing forth from Greenbelt, MD. “We’ve now laid the cornerstone of a unified cosmic theory…We have not answered all the questions. But we’ve certainly turned a corner.” Thanks to NASA and the Wilkinson Microwave Anisotropy Probe (WMAP), scientists now have visual evidence of the universe’s origins with which to test out all the prevailing cosmological theories. Great news! Not only is any new empirical data in this field a boon to science, but, if ridiculous amounts of new information are gleaned from just this one little probe…well, it won’t help NASA in the manned space department, but the agency could still use a few unmitigated victories these days. On another note, looking at this map brings back some old memories. For my high school science thesis (required at SCGSSM), I used similar COBE DMR data to figure out that early galaxies displayed a fractal distribution. (Hey, it was the early ’90’s – fractals were the rage.) I wonder if this new data bears out that old rinky-dink thesis.
Ghosts in a Machine.
Particle physicists plan to build a “neutrino factory” in the UK. I almost spent a summer in high school searching for neutrinos in a Spanish mine (as part of a mandatory science thesis), until at the last minute I switched to an astrophysics project instead. Examining cosmic background radiation for fractal patterns…very trendy at the time.
Schroedinger’s Universe.
Discover interviews physicist John Wheeler about the quantum nature of reality. “Wheeler conjectures we are part of a universe that is a work in progress; we are tiny patches of the universe looking at itself – and building itself. It’s not only the future that is still undetermined but the past as well. And by peering back into time, even all the way back to the Big Bang, our present observations select one out of many possible quantum histories for the universe.” (Via Anil Dash.)