Saturday, December 31, 2011

Burned Again

During the week of December 19, the library at Cairo's Institut d'Egypte was set afire. Security forces failed to respond to the fire, though their headquarters were close by. The Institute was founded by Napoleon after his 1798 conquest of Egypt. In the wake of his invasion, Napoleon brought with him many scholars who made discoveries like the Rosetta Stone. The library contained about 200,000 volumes, a priceless resource of Egyptian history.

Carl Sagan's COSMOS recalls the burning of Alexandria's library, the greatest of its time. More than a repository of scrolls, the library was a center of study and scholarship, what we would today call a university. Supposedly it contained a complete history of the ancient world, knowledge now lost. Among those who held the title of Head Librarian were Erastothenes, who in the 3rd century BC calculated Earth's circumference; and Aristarchus, who in the 2nd century BC suggested that Earth was not centre of the universe. Euclid and Archimedes also studied at the library,

In COSMOS we read about Hypatia, the last librarian of Alexandria and a woman famed in her time for mathematics. She was also a philosopher and astronomer. Alexandria's library was burned several times: by Julius Caesar's forces in 48 BC, by the Roman Emperor Aurelian in 270 AD, by the Coptic Pope Theophilus in 391 AD, and by Muslims in 642 AD. Hypatia was horribly murdered by a mob in 415 AD. (Sagan's book takes some liberties with history, linking her death with the burning of the library).

Has humanity advanced in these thousands of years? The historical record shows that burning of books can be a tactic of any philosophy. Today in our computer age we have censors trolling the internet and Arxiv deleting or attacking what does not agree with them. What has not changed is that we must always be vigilant against those who would burn books. Those who would burn books will also burn people.

From ancient times until this month some people will try to burn libraries. Erastothenes' spherical Earth, Aristarchus' cosmology, and the achievements of Hypatia outlived them by thousands of years. Discoveries about nature are truths that can not be censored. If the speed of light slows down or a Black Hole exists nearby, no human censorship can prevent it.

Thursday, December 15, 2011

Air Launch


Microsoft billionaire Paul Allen has announced plans with Scaled Composites to build the world's largest airplane, with a wingspan of 120 meters. This huge bird would look like the Wings Over the World aircraft in HG Wells' THINGS TO COME. It would be first stage of an air-launched orbital booster system developed with SpaceX. The 5-engine rocket looks like SpaceX's cancelled Falcon 5/Dragon, which would have a launch weight of 130 tons. In theory such an air-launched booster offers many advantages, as described in the 3-minute video.

Paul Allen has spent money encouraging Space before, as when he put up funds for the 10 million dollar X-Prize. This project would be 2-3 orders of magnitude bigger. As Howard Hughes and others have found, building a plane this size from scratch is incredibly expensive. (The Airbus A-380 cost about 15 billion to develop). The hangar door in the animation is nearly 150 meters wide! Before building the 747, Boeing first needed to construct the world's largest building in Everett, Washington as an assembly line.

The aircraft design in this animation looks like it has not been completely developed, unlike the stunningly original aircraft that Scaled is known for. For example, a pressurised aircraft would not have straight fuselage sides. The center section may need to gain area. A larger center section provides more lift, structural strength, and access between the hulls. Perhaps the designers will consider using two existing 747 or C-5 Galaxy hulls and twinning them with a new center section.

NASA studied such twinned aircraft in the 1970's. A major issue is runway width. The standard airport runway is 45 meters wide. Runway 12/30 at Scaled Composites' home in Mojave is 60 meters wide, but rated for aircraft of no more than 120,000 pounds. The concrete strip in the animation appears to be about 90 meters wide and very long. Building one such runway would cost around a billion dollars, and you would need one every place this bird would land. Emergency landings at other fields would be unthinkable.

Since the new 747-8 freighter has a payload capacity of 135 tons, they could also consider launching their 130 ton rocket from atop one. It will not be the first time a 747 has launched a Space Shuttle! In the 1970's NASA considered using giant twin airplanes as Shuttle carrier aircraft, but settled on the familiar 747. Developing an all-new aircraft was considered too expensive.

The dreamers behind this project deserve every encouragement. Hopefully they realise the challenges of such an enormous project. NASA has studied giant twin-hulled aircraft since the 1970's. We can hope that Paul Allen and allies can improve on the past.

Monday, December 12, 2011

Peace Wins Over Darkness

Back in October, Darkness Can Not Drive Out Darkness, this blog pointed to the three women who shared this year's Nobel Peace Prize. Ellen Johnson Sirleaf, Leymah Gbowee and Tawakkol Karman bring more light to the world than "dark energy." In Sunday's New York Times they were hailed again:

"In a ceremony in Oslo that repeatedly invoked gender equality and the democratic strivings of the Arab Spring, the 2011 Nobel Peace Prize was presented to three female activists and political leaders on Saturday for 'their nonviolent struggle for the safety of women and for women’s rights' as peacemakers."

Sunday's Times contained no mention of the three men who divided up the Physics Prize. Perhaps claiming discovery of "dark energy" does not interest the Times writers anymore. Hint: try rewarding a woman from a challenging background. Only two women have been given the Physics Prize--Marie Curie in 1903 and Maria Goeppert Mayer in 1963. The day she wins the Physics prize will easily make the front page.

UPDATE: Nick Suntzeff, co-founder of the High-Z supernova search, quoted in Eric Berger's Houston Chronicle blog:

"This must be perhaps the only Nobel Prize ever awarded for a discovery for which we have no explanation, not even an inkling of one."

Labels:

Wednesday, December 07, 2011

Pearl


Aloha! Here are a few photos from Pearl Harbor as it looks today. The Captain's chair of the battleship USS Missouri. The ship is covered in steel plate in some places 18 inches thick! They don't build ships like this anymore.

An unforgettable view out the Missouri bridge windows to the USS Arizona Memorial. US involvement in the war began with the attack here 70 years ago and ended with the surrender ceremony on Missouri's deck in Tokyo harbor.

The Pacific Aviation Museum on Ford Island. This B-25 bomber is in the colours of Doolittle's raiders. They launched from USS Hornet to bomb Tokyo.

The 16-inch gun turrets. Missouri and other Iowa-Class battleships carried 9 such giant rifles. They could each fire a 2700-pound shell 40 kilometres! Due to Earth's curvature a battleship can only fire as far as it can see, leaving the advantage to aeroplanes. For centuries ships with cannon dominated naval warfare.

Isaac Newton saw warships armed with cannon. He saw that the faster a cannonball is fired, the farther it travels. Newton deduced that a projectile moving fast enough would "fall" around the Earth's curve, becoming a satellite. The farther a satellite orbits from Earth, the slower its velocity. Newton surmised that the Moon's orbit followed the same law of gravitation.

If Newton were alive today he would see that particles of light (photons) appear to travel at the same velocity. He would also see evidence that Space/Time began at a tiny point, called a "Big Bang." As the Universe gets older, every point in Space/Time travels farther from that initial singularity.

Perhaps Newton would deduce that gravitation affects all particles, even those of light. Just as satellites circle the Earth, he might surmise that photons are locked in orbit around a "Big Bang." As light particles move farther in Space/Time from the Big Bang, their velocity must also slow.

GM=tc^3. Where G is Newton's gravitational constant, M and t are mass and age of the Universe. As time t increases, speed of light c is predicted to slow. Newton's laws continue to guide our spacecraft to the planets. The power of ideas lasts longer and travels much farther than a battleship's guns.

Labels:

Locations of visitors to this page