Monday, April 30, 2007

Science of STAR WARS


Cockpit of the Millenium Falcon. May is the 30th anniversary of the first STAR WARS movie (now called A NEW HOPE.) Monday April 23 was an anniversary showing at the Motion Picture Academy in Beverly Hills, attended by George Lucas and some of the other makers. There was also an exhibit of models and costumes at the California Science Centre.

Since it is the anniversary of this enjoyable series, I will write in defence of the "science." Many people complain that spaceships don't make noise in a vacuum, but who is to say that Space is completely empty? Even hundreds of kilometers from a planet, there is enough atmosphere that a space station's orbit decays. STAR WARS spaceships battle close to planets, and don't venture into deep Space without the hyperdrive. Perhaps with sensitive enough microphones you could hear the ships roaring by. Rocket engines leave a lot of gas in their wake, through which sound travels.

Some have also complained that STAR WARS fighters bank like aircraft. There are actually two reasons for this. The X-Wings and Millenium Falcon must have engines on their undersides for takeoff and landing. By rolling in the direction of a turn, they can use those thrusters to change direction in a hurry. Harrier pilots do this in a maneuver called VIFF, Vectoring In Forward Flight.

Another reason to bank is the "G-forces." STAR WARS fighters don't seem to have any system compensating for acceleration. Everyone like me who has spent time in military aircraft will attest that the only way to make a high-G turn is to bank. Then the forces of acceleration hit the pilot eyeballs-down. Otherwise pilots would black out or worse.

Our civilisation has yet to experience a Space war. With our limited experiments of Strategic Defence, we have seen how difficult it is intercepting a rocket approaching you at thousands of kilometres per hour. Even in our age of guided missiles, pilots always try to intercept a target from behind. The Death Star gunners have great difficulty shooting down attackers from fixed positions. The best way to intercept a spacecraft may be to do like Darth Vader, get into your own spacecraft and shoot at Luke from behind.

My discovery about the MILLENIUM FALCON: There is a set of 4 forward guns right above the cockpit. You can see them in the scene when they come out of hyperspace into an asteroid field. The guns are visible on top of the frame. As a TIE fighter passes by, Han hits a switch and we see the guns fire. Those guns are also used to shoot at Darth Vader in the end of the movie. They could not have used the turret guns because Han and Chewbacca are both seen in the cockpit. We saw earlier that the turrets need someone inside to be fired. Perhaps someone should write a paper on this.

MORE thoughts about STAR WARS and courage at They Found the Remains of a Rebel Base.

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Friday, April 27, 2007

New World


Astronomers at the European Southern Observatory have discovered an "Earthlike" planet orbiting star Gliese 581, only 20.5 light-years away. This planet (foreground) has mass 5 times that of Earth and orbits the star every 13 Earth-days. Because Gliese 581 is a dim red dwarf, this leads to conditions favourable to life. The planet's mean temperature is between 0 and 40 degrees Celsius, suitable for liquid water.

Our own planet occupies a very narrow habitable zone, where the porridge is neither too hot nor too cold. As we have seen before, Earth's temperature has remained comfortable because light has been slowing according to GM=tc^3. The same equation that keeps our Sun relatively stable applies to Gliese 581 and any other star. If c did not slow, the habitable zone would expand to pass Earth by. Life would have difficulty evolving on any planet anywhere.

The High Altitude Radial Velocity Planet Searcher (HARPS) mounted on the 3.6 meter telescope has discovered many planets. Around Gliese 581 it has also discovered a Neptune-sized planet, pictured in blue, orbiting the star every 5 days. In the distance another planet orbits in 84 days. The painting is very pretty; one can easily imagine some future starship enjoying this same view.

We can only imagine what sort of life would evolve here. This planet's gravity would be about 2.2 times that of Earth, so they might be more solidly built. Since the star's light is redder than ours, their eyes would be sensitive to longer wavelengths, as a snake can see in infrared. Our red would be white to them.

(ESO, are you there? I appreciate the notices but the lighting is all wrong. The "Earthlike" planet seems to be lit from a yellow Sun-like star somewhere off to the right. The blue Neptune-like planet seems to be lit from a different source entirely. Many science fiction movies make similiar mistakes. I can happlily correct this painting for you. )

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Thursday, April 26, 2007

Hawking Closer to the Sun


Our Sun imaged by STEREO, the Solar Terrestrial Relations Observatory. The twin STEREO spacecraft allow 3-D images of the Sun and surroundings. Best wishes to Stephen Hawking, for today was the day of his long-awaited zero-G flight. Desire to slip the surly bonds of Earth is far older than humanity, as symbolised by Icarus' flight. Hawking's biggest discovery may have a lot to do with the Sun.

There are many unsolved mysteries about the Sun. The temperature of its surface is thousands of degrees, yet the corona is millions of degrees. The corona is laced with magnetic fields which contribute to its high temperature. The sunspots which Galileo saw mark the locations of magnetic field lines. Solar flares related to sunspots affect communications on Earth and could be a great hazard for interplanetary flights. Solar variations are part of the debate on Earth's climate. Though life on Earth depends on the Sun, we are far from understanding it.

According to the standard solar model, when Earth was formed the Sun shone with only 70% of its present luminosity. Earth’s surface would have been frozen solid, making evolution of life very unlikely. Geology and the fossil record contradict this prediction. The very appearance of life on Earth conflicts with the model. This conflict with observations was the Faint Young Sun paradox. Because the Sun turns fuel into energy according to E=mc^2, change in c precisely accounts for this paradox. If c had not changed in precisely the amounts predicted, life would not have evolved to read this post.

Hawking's biggest discovery was that Black Holes are not completely black--they tend to radiate as blackbodies. Hawking first presented his results in a talk entitled "Black Hole Explosions?" When he had finished, the moderator said, "Sorry Stephen, but this is absolute rubbush." At least Hawking was allowed to finish. Within a few years people realised that Stephen was right, and scientific fame followed.

One big mystery about the Sun is how it formed in the first place. We know that stars form from collapsing disks of gas, but how the fusion reaction begins has been a complete mystery. If the gas cloud were heated, it would dissipate before a sustained fusion raction could begin. The disk's angular momentum would also be carried off into Space. Something else is needed to trigger a cloud's collapse into a star.

If tiny Black Holes collided with a gas cloud, they would not suck everything up. The tiny amount that they did eat would produce an immense amount of Hawking radiation. Heat and the gravitational pull of a singularity would ignite a star and keep it steadily burning for billions of years. A Black Hole could exist in the second last place humans would look for one, in front of our face each morning.

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Monday, April 23, 2007

A New Class of Pulsar


At the Royal Astronomical Society meeting last week in, astronomer Gregg Hallinan announced discovery of a new class of brown dwarf that is also a pulsar. Object TVLM 513 sends out a bright flash every 1.96 hours. The brown dwarf also has a powerful magnetic field guiding the beams. The processes behind this are completely unknown. Previously brown dwarves were thought to be boring, an intermediate class of objects between gas giants and stars. They exist in unknown numbers in interstellar Space.

A supernova leaves in its aftermath a neutron star, composed of matter so dense that a spoonful would weigh a ton. Some neutron stars are pulsars, emitting spinning jets of radiation. Cause of these jets has been another mystery. When Jocelyn Bell discovered them in the 1960's, some thought the radio pulses were from ET's. The jets do not coincide with the neutron stars’ axis of rotation, causing them to spin around like a lighthouse. Something else inside the neutron star creates the jets.

Other neutron stars are magnetars, objects with magnetic fields so powerful that they defy Maxwell’s equations to describe them. Once again, jets of radiation and a magnetic field are telltale signatures of a hidden singularity. It would rotate independently inside a neutron star, producing both a spinning beacon and magnetic field.

In an old Sci Fi movie, the pilot is heading into a mysterious void. Motion of stars tells him that the ship is accelerating, though he can't feel a thing. His instruments also tell him that there is nothing in front of him, yet he is inexorably drawn forward. Turn back while you can--It's a Black Hole!

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Thursday, April 19, 2007

Vision


For the entertainment of Darnell and others who dream about Space, here is technology that no human has seen. This slide was shown to a room full of physicists and not one figured out what it is. Like Kea's drawings, it may be too simple to understand. This could be the natural development of your planet, many decades from today.

Radial lines rise from the oceans, located over the centres of population and industry. Alpha is at longitude 100 West, over the Americas. Beta is at 140 East to serve Japan, Australia and East Asia. Gamma is at 80 East near the Indian subcontinent. Delta is at 20 East over Africa and Europe. By an amazing coincidence, the configuration resembles a peace symbol with Earth at its centre. Let us hope that it inspires humans to peaceful cooperation.

In the climax of Arthur Clarke's FOUNTAINS OF PARADISE, the dying hero envisions multiple Space Elevators connected by giant bridges 36,000 km over the Earth. That would securely brace the system against oscillations, making stability problems disappear. Once the radial lines are in place, connecting them with a Ring is a comparatively simple project. If Saturn and other gas giants can be decorated with Rings, why not Earth? The Ringworld can serve as an anchorage for giant rotating Space habitats. There is room for billions of people, with easy access to the resources of Space.

The nodes are also the best locations for singularity power. Power stations could beam energy to their respective regions of Earth. If Black Hole energy is not developed, this vision could alternately be powered by the Sun. The Ringworld could be dotted with solar power stations, an indirect way of tapping Black Hole energy. As seen in our redwood forest, life tends to seek the Sun as it grows skyward.

In the forest, the growth of trees builds an entire ecosystem. The redwoods create a habitat for creatures from insects to birds. Here the driving force is humanity, the only species capable of reaching Space. Like the redwoods, humans bring other life forms with them--plants, crops, fish, pets and nearly every other creature grown on Earth. The planet itself could someday return to a natural state. Earth would be Central Park and museum in the midst of a city.

We began the week in a redwood cathedral, observing how life naturally grows toward the sky. Nearly all humans dream about flying. The desire to reach Space may be as old as life on Earth. That life began deep underground, eventually moving to the oceans, to the land, and into the sky. Now a species has developed the ability to leave the planet completely. This simple picture shows a future in which all humans, along with other forms of Earth life, can someday reach the stars.

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Wednesday, April 18, 2007

Top of the Elevator


Space Elevator model displayed at International Space Development Conference in May '006. As we mourn the tragic events elsewhere in the world this week, we should not forget that many things are looking up. Quietly, without fanfare, many people are working toward a better future. This week has much news about Space Elevators.

The Space Elevator was mentioned by Konstantin Tsiolkovsky, and described in detail by Yuri Artsutanov in 1960. (Arthur Cllarke noted that it was years before anyone took Artsutanov seriously.) The idea is so simple that it has been invented multiple times. We have become used to the geostationary satellites that bring us telephone calls and Direct TV. If a cable could be lowered from a satellite to the Earth, we could theoretically run payloads to Space like an elevator. The main ingredient needed is a strong enough cable. Carbon nanotubes present the best hope.

The Elevator is such an attractive idea that many private companies have formed hoping to profit from it. Liftport Inc. in February '006 tested a 1 km cable suspended from balloons. Unfortunately this week Liftport was unable to pay rent on its headquarters. This should not stop them, for many successful companies have begun in garages. Also this week, Tethers Unlimited launched their Multi-Application Survivable Tether (MAST) experiment into orbit. MAST will unreel a 1 km cable to tethered satellites, one small step for a cable but a giant leap for technology.

Most plans for Space Elevators have them based on large offshore platforms. For the moment we will assume that the United States chooses to stay ahead in Space. The best location would be on the equator at 100 degrees West, nearest the geographic centre of North America. This area of the Pacific is convenient to US cargo ports and patrol by the US Navy. (The biggest US seaport is Los Angeles/Long Beach.) If the US chooses not to be a leader in Space, they can always go the way of Rome.

100 West is also an ideal location for a power station. Electricity from Space has been studied since 1968, envisioning fleets of enormous solar arrays in orbit. This has been considered too expensive, but new physics may make it practical. Recently the US Defence Department has taken an interest in solar power satellites to power their hardware. This would not be the first time that the military has led in technological development. The technology for beaming electricity could be used for something even better.

As has been hinted here before, power generated from a singularity would be far more efficient then even nuclear fusion. Such a power station would not be located on Earth; geosynchronous orbit is best for multiple reasons. As with solar power, electricity would be sent to Earth via microwave or laser. From 100 West, electricity could be beamed to any part of the Americas. With a Black Hole in your pocket, you need just one satellite without solar panels.

As with ISS, these projects could be built with international partners. A second Station and Elevator could be sited at 140 degrees East, near the world's second biggest economy in Japan. Here it could also serve the needs of Australia and coastal China. As Arthur Clarke forecast, a location at 80 degrees East could serve the Indian subcontinent. All these nations would be encouraged to cooperate and share the benefits.

The Space Elevator faces many technological hurdles, starting with production of a strong enough cable. The promises are too great to ignore. It offers the possibility of routine travel to orbit without rockets. Many groups public and private are studying the concept. TOMORROW: We'll see what kind of world that could lead to.

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Monday, April 16, 2007

Fun Things to Make With Carbon


Any Space traveller needs some chemistry. Kea has good posts about Earth's climate. Even before the current controversy, it was clear that humans put too much junk in the atmosphere. There are better things to do with carbon than spewing it chaotically into the atmosphere. Despite claims that the Universe will end in chaos, new structures are continually being created. Even in parameter space, nature has created a tree of life.

Life on Earth, from microbes to redwoods, is based on carbon. In nature carbon takes many forms, from the graphite in pencils to diamonds. Before Buckminster Fuller invented geodesic domes, nature was already creating them. In 1985 researchers discovered Carbon-60 occuring naturally in soot. Because of its shape, this molecule was named the Buckminster Fullerene or Buckyball. More recently physicists have discovered other forms of fullerenes. like the nanotube.

Graphene (pictured above) is the thinnest possible molecular materiel, a single layer of carbon molecules. Physicist Walter de Heer at Georgia Institute of Technology pioneered the production of graphene from silicon carbide wafers. (His funding grant was rejected by NSF, but Intel saw a good thing and funded his experiments.) Since 2004 Physicist Andre Geim at University of Manchester has produced graphene by an amazingly inexpensive process. He placed graphite flakes on a piece of ordinary Scotch tape. By folding and refolding the tape he produced flakes just one molecule thick. You can do good science on the cheap.


Carbon nanotubes are cylindrical fullerenes, sheets of graphene rolled into tubes less than one nanometer thick. Their tensile strength has already been added to existing materiels. Thanks to nanotubes, Floyd Landis' bicycle in the 2006 Tour de France had a frame weighing only one kilogram! So far researchers have been unable to produce nanotubes in long fibers. Mass production of nanotubes would have many applications, from stronger bridges to Space.


(Spider-Man's webbing has enormous tensile strength. Since Spider-Man is a carbon-based life form, one suspects that his webbing contains carbon nanotubes.)

Arthur Clarke's novel THE FOUNTAINS OF PARADISE is set in motion by the introduction of "hyperfilament." This sci fi materiel is described as a continuous pseudo one-dimensional diamond crystal, which could be a rough description of nanotubes. In the novel it can only be produced by micro-gravity factories in orbit. In Clarke's novel, hyperfilament allows construction of the first Space Elevator. TOMORROW we'll see one possible destination.

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Redwood Cathedral


Nearly everyone has expressed a wish to someday travel in Space. We'll see that the desire to escape Earth's gravity is as old as life. This week you'll see an entirely new vision, where BILLIONS of people live in Space, without rockets. Before we get into that, we must learn from beings far older than us.

Scientists need to get their heads out of computers and take a walk in the woods. The oldest known redwood tree was 2200 years old, dating from before the time of Christ. Redwood species date from 110 million years ago. During the Cretaceous era of dinosaurs, they grew in all parts of Earth. The tallest of living things survived mass extinction 65 million years ago and survive mostly in foggy valleys of coastal California.

The highest known redwood tree is 112 meters, tall as a Saturn V rocket. Its needles absorb water from the coastal fogs, allowing the highest reaches of the tree to remain hydrated. The bark is armour nearly a foot thick in some places. When exposed to fire, the bark forms an ablative shield, similiar to the Apollo heatshield. (The Shuttle thermal protection system--fragile, expensive, difficult to apply and maintain, was not ablative.) Redwood is chemically resistant to termites and so tough that it was used as a separator inside batteries.

No one knows if trees have religion, but they build many cathedrals. When a redwood dies, seedlings grow around it's remains in a circle. The trees lining this cathedral are clones, genetically identical to the progenitor. Redwoods have learned to survive without sex, for only 20% of their reproduction is sexual. By producing seedlings, a single tree can survive indefinitely. The redwood's life cycle shows great faith in the future.

A redwood forest harbours more biomass per unit area than any other region of Earth, including rain forests. As a redwood grows toward the sunlight, it brings many other life forms with it--ferns, birds, mammals, insects and the ever-present microbial life. Life first thrived deep within Earth, warmed by internal heat. It began with organic chemicals from the stars, and has since been trying to get back. Life expanded outward to the oceans, then to land, eventually climbing trees toward the sky.

This walk in the woods has much to do with spaceflight. As we can see from observing Earth life, the desire to reach Space is far older than humans. Alarmists will always clamor that the Universe will end in chaos or "dark energy," yet life continues to create more complex forms. As Space/Time expands, growing outward into Space is a natural part of life.

NEXT: More fun things to make with carbon.

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Sunday, April 15, 2007

Don Ho and Geodesics

Hawaii mourns the loss of entertainer Do Ho. My childhood memories include his theatre, a big geodesic dome on the grounds of the Hilton Hawaiian Village in Waikiki. Perhaps this big bubble was an echo of "Tiny Bubbles." Buckminster Fuller's geodesic domes were somewhat popular in the 1960's and 1970's. Today both Don Ho and his dome are no longer with us, but his daughter Hoku continues to perform.

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Thursday, April 12, 2007

Happy Anniversary


April 12 is Yuri's night, celebratingh the anniversary of Gagarin's 1961 flight. Exactly 20 years later April 12, 1981 was Space Shuttle Columbia's first flight. This was no design, but an accident caused by combinations of flight delays. The Shuttle did make Space flight more routine than it was for Gagarin, but never achieved the hope of airline-like access.

Many errors were made in the shuttle programme. Abandoning the Apollo/Saturn hardware was a huge mistake. It would have benefitted the US to develop a smaller spaceplane first, like the X-20 Dyna-Soar. A spaceplane came in handy during the movie MAROONED. ISS is limited to a crew of three because a spaceplane escape vehicle was cancelled for budget reasons.

The big delta wings are not necessary. Originally Shuttle was designed with stubby wings, like the X-15. When the US Government Accounting Office concluded that Shuttle was only economical if it replaced every other booster, NASA responded by cancelling every other booster. This forced the Air Force to adopt Shuttle, for which they demanded a larger payload diameter and cross-range capability. Supposedly the heavy wings would allow Shuttle to land at Air Force bases, a capability that was never used. The wings add weight and drag, but do provide a big target for foam strikes.

Today I've been working on a technology that will make human spaceflight safer, cheaper and far more comfortable. I hope to be able to write about it sometime.

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Thomas Gold Was Right and Wrong

Often the most original insights in a field of study come from outside. My book research shows that many great minds were polymaths, interested in many subjects. Continental Drift was promoted by Alfred Wegener, who trained as an astronomer and became a leader in meteorology. Though it seems obvious from the fit of coastlines, during Wegener's lifetime few accepted that the continents could move. Today's theory of plate tectonics is a vindication of Wegener.

Astrophysicist Thomas Gold died in 2004. During his long career he made many contributions to physics and astronomy. Unlike many scientists, Gold was willing to risk being wrong. Many of his ideas turned out to be right. When pulsars were discovered by Jocelyn Bell in 1967, some thought they could be signals from ET's. Gold and Fred Hoyle identified them as rapidly spinning neutron stars. The source of neutron stars' rotating beams has remained a mystery, but they could be explained by internal Black Holes.

Gold and Hoyle also promoted a "Steady State" universe. This model universe did not expand--redshift of distant objects was usually explained by a slowing speed of light. The steady state was an alternative to what Hoyle derisively named a "Big Bang." Who knew that this insulting name would catch on? Discovery of the cosmic microwave background in 1965 discounted the steady state. The 2.7K radiation showed that the Universe evolved from a hotter, denser state.

Note that a modern theory of R = ct predicts a Big Bang. Redshifts would indeed be caused by expansion. Change in c would not cause redshifts, but would make high redshifts curve upward. That might lead a naive person to think that the universe was accelerating due to "dark energy."

We were taught in school that petroleum is produced from decomposing fossils, hence the term "fossil fuel." Gold, following some Soviet scientists of the 1950's, took the maverick view that petroleum is abiogenic. Under this theory oil forms deep within the Earth, cooked by Earth's internal heat and aided by bacteria living many kilometres underground. Bacteria would explain the organic compounds found within oil. Under this theory, Earth contains far more petroleum than previously thought and is still producing it.

Was Gold right or wrong about oil? The abiogenic theory is still a minority view, but recent discoveries lend support to Gold. The deepest hole ever dug, the Kola Superdeep Borehole, found bacteria living at depths of 6.7 kilometres. We have found "extremophiles" living in all sorts of inhospitable environments. Moons such as Titan and possibly the planet Mars are still producing methane due to some mysterious process. Earth herself produces an unknown amount of methane, which leaks into Space through volcanic and oceanic vents. Production of these hydrocarbons is indirect evidence supporting Thomas Gold.

The amount of energy produced by Earth's interior is only a guess. The old hypothesis of "radioactive decay" is not adequate to explain even Earth's known heat production. If Earth leaks a large amount of methane, that is even more energy that must be accounted for. Something else is keeping Earth's interior hot, producing vulcanism and also hydrocarbons.

The first stars did not form until hundreds of millions of years after the Big Bang origin. In the early Universe of quasars and active galactic nuclei, the primary source of energy was Black Holes. Hidden from sight, they may still be producing energy. Thomas Gold thought that Earth's internal heat is still producing oil. The petrol in your tank may be energy from a tiny Black Hole.

UPDATE: This doesn't imply that we should waste hydrocarbons. Even if Earth is still producing oil, humans have been using it far faster.

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Wednesday, April 11, 2007

An Asteroid, A Fisherman, Oil and Tortillas


In between posts about maths, Kea has many good posts about our misuse of fossil fuels. Tommaso's trip to the Yucatan inspired some good posts too. Mexico's Cantarell oil field is running out of oil. This story began with an asteroid impact and affects even the price of tortillas.

65 million years ago the Chixculub meteorite struck near Yucatan, ending the age of dinosaurs. It also created a unique geological formation beneath the gulf seabed, cretaceous dolomite thrust upward to form an oil reservoir (pink). In 1971 a fisherman named Rudesindo Cantarell noticed that his nets were getting covered with oil. He had stumbled upon the world's second biggest oil field after Saudi Arabia. Like a subsurface volcano, this gusher produced 2 million barrels of oil per day.

The gift of oil has ruined many a developing country. This follows predictable steps: 1) Nationalise the oil industry under your control, 2) Keep your own party in power by promising the people huge benefits from oil, 3) Make everyone so fat from oil money that they don't develop other industries, 4) Keep out foreign oil expertise until your resource is ruined. Mexico's oil industry is the state monopoly PEMEX. Nearly half of the 53 billion dollars that PEMEX hands to the government comes from Cantarell. This huge sum keeps Mexico's government afloat but prevents investment in technology or exploration.

PEMEX's outdated technology is starting to catch up with them. From January '006 to February '007 Cantarell lost 20% of its production. Oil is one of Mexico's 2 biggest sources of currency, along with remittances from workers in the US. Within 8 years Mexico may become a net oil importer, with disastrous effects for its economy.

Mexico is not alone in mismanaging resources. Iran imports nearly half of its gasoline, having only one petrol-producing refinery within its borders. A single British warship could shut it down and knock out Iran's lights. The US has not built an oil refinery in 30 years. The cost of business in the US makes it more profitable to outsource oil production. From the Middle East to Venezuela, the gift of oil has led many countries to dictatorship.

(According to OPEC, Venezuela's oil production has dropped by 1 million barrels per day since 1999. To keep production going, Venezuela's state-owned oil company borrowed 11 billion dollars this year. The government spends 9 billion annually in subsidies to keep the price of petrol down. This is how to go bankrupt.)

Mexico is the birthplace of corn, but today imports most of its corn from the US. With the price of oil increasing, Americans have taken an interest in ethanol fuel. This has increased the price of corn 80 percent in the past year. Because of speculation and hoarding, the price of tortillas has risen enormously. Paying more for Mexico's staple food hits people straight in the belly.

All this was started by an asteroid that fell from the sky. The chemicals our lives depend on, even water, came from such impacts. From petrol to the food we eat, our lives are intimately connected with Space. The heat that produces oil may originate in a tiny primordial Black Hole. Let us hope that we learn to manage these gifts.

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Tuesday, April 10, 2007

Kathy Sierra and the Aftermath

Until a short time ago, few people had heard of Kathy Sierra. She is a woman in her forties, writes books, blogs about technology issues, and as far as is known has never harmed anyone. During the week of March 29 Sierra was subject to vile personal attacks. These included death threats, misogynist comments and a photoshopped picture of her being strangled in underpants. She felt compelled to cancel plans to speak at a tech conference.

In response to the treatment given Kathy and others, her publisher Tim O'Reilly of O'Reilly media has proposed a blogger code of conduct:

1. We take responsibility for our own words and for the comments we allow on our blog.

We are committed to the "Civility Enforced" standard: we will not post unacceptable content, and we'll delete comments that contain it. We define unacceptable content as anything included or linked to that:

- is being used to abuse, harass, stalk, or threaten others
- is libelous, knowingly false, ad-hominem, or misrepresents another person,
- infringes upon a copyright or trademark
- violates an obligation of confidentiality
- violates the privacy of others

2. We won't say anything online that we wouldn't say in person.

3. We connect privately before we respond publicly.
When we encounter conflicts and misrepresentation in the blogosphere, we make every effort to talk privately and directly to the person(s) involved--or find an intermediary who can do so--before we publish any posts or comments about the issue.

4. When we believe someone is unfairly attacking another, we take action.
When someone who is publishing comments or blog postings that are offensive, we'll tell them so (privately, if possible--see above) and ask them to publicly make amends. If those published comments could be construed as a threat, and the perpetrator doesn't withdraw them and apologize, we will cooperate with law enforcement to protect the target of the threat.

5. We do not allow anonymous comments.
We require commenters to supply a valid email address before they can post, though we allow commenters to identify themselves with an alias, rather than their real name.

6. We ignore the trolls.

Thank you, O'Reilly. When someone has something constructive to say, there should no problem with revealing the commenter's identity. The majority of "anonymous" comments are negative. They are a venue for personal attacks, false allegations and comments polluting friends' blogs. Personal attacks are an attempt to distract from someone's ideas and undermine her support. Educational level makes no difference, for some of the worst attacks have come from PhD's. Given past experience, the anonymous comment is a weapon which humanity lacks the wisdom to use.

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Sunday, April 08, 2007

Red Lights


I hope everyone enjoyed the Easter holiday. This has turned into an extraordinarily productive week.

HD 44179, nicknamed the Red Rectangle. This dying star displays a mysterious glow called Extended Red Emission. The phenomenon permeates the Milky Way but its source has been a mystery. A new computer simulation claims that the glow is caused by molecules in interstellar Space. There is still room for your own interpretation. Dark matter? A disk of tiny primordial Black Holes?

Steinn Siggurdson continues to post on the fate of NASA's Beyond Einstein programme. Not long "dark energy" was touted as increasing funding and trips to Stockholm. Now we see the red lights of an approaching train wreck. As reported back in February, it has come down to a cutthroat competition between missions, with a possibility of none surviving.

"No one is going to win this, only lose. It should never have come to this. The stakes are high; literally thousands of scientists are looking at the core science activity they have chosen to work in being annihilated for 10-20 years, a lot of junior people could be dumped from science, a lot of senior people could look at having the field they worked to build being shut down."

People think that GM=tc^3 has problems? Mother would say: remember that other people have bigger problems than you. Big science lives in perpetual fear of falling out of the funding line. Fortunately NASA has generously provided this writer with a purple BEYOND EINSTEIN pen. All one really needs to go beyond Einstein is a good pen.

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Friday, April 06, 2007

Why It Slows


Many of you have seen bits of this lecture before, so thanks for your patience. I will conclude with a new way of visualising c change.

An important lesson from Relativity is that Space and Time are really the same phenomenon. Humans are already hardwired to think this way. Few people know exactly how many kilometres are between work and home, yet most know how long it takes to reach work, often down to the minute. We are used to saying "8 minute drive" or "30 minutes away." The conversion factor is the speed limit of your vehicle.

Intervals in Space/Time are either Spacelike or Timelike. The lightcone follows the metric dr = cdt. Outside this cone, the interval is Spacelike. An event at the lightcone's origin can not affect an event outside. Inside the lightcone, the interval is Timelike. The difference is literally a matter of Time. The conversion factor here is Nature's own speed limit, the speed of light.

The local conditions of Special Relativity, which does not allow for gravity, are part of the curved Space/Time of General Relativity. There is no centre in Space, for every bit resembles every other bit. There is a centre in Time, called a "Big Bang." Our timelike separation from this origin is age of our Universe t, about 13.7 billion years. Now we state a simple principle: The characteristic scale, or radius of curvature R = ct. This is why, as t increases, the Universe expands. That is what powered the Big Bang and continues to drive expansion today.

The Universe can't expand at the same rate forever, because mass and gravity slow it down. Gravity then requires that:

GM = tc^3

Where G is Newton's gravitational constant, M is mass of the Universe. When t was tiny c was enormous, and the Universe expanded like a Bang. As t increases, expansion slowed due to gravitation and continues slowing asymptotically to this day. The curvature radius R, the Schwarzhild radius of a Black Hole, photon wavelengths, and even the size of magnetic fields increase at exactly the same rate!

Here's another way to explain c change. Photons can be thought of as satellites orbiting around the "Big Bang" origin. If you were an astronaut in low Earth orbit, satellites whizzing by your altitude in circular orbits would all have the same velocity. As a satellite's altitude increases, velocity goes down. Every photon that passes by at that moment has the same velocity and timelike separation from the Big Bang. As the Universe expands, that separation grows. Velocity of photons thereby decreases at a very small rate.

As you see, these equations are simple enough for a child to understand. Yet it has taken humans centuries to figure this out. Most physicists still can't explain it, leading to "dark energy" and other epicycles. Is it not fun to discover something simple?

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Thursday, April 05, 2007

A Brief History of c Change

In response to multiple requests, here is how humans began to suspect that c slows down. A changing speed of light is an old idea that somehow is not taught in schools. For much of history humans did not know whether light had a finite speed at all. Philosophers from Aristotle to Kepler thought the speed of light was infinite. Kepler's friend Galileo performed many experiments with nature, including an attempt to measure the speed of light.

Galileo described stationing observers on distant hilltops with covered lanterns. The first observer would uncover his lantern, and upon seeing a light the second observer would uncover his. In this way Galileo hoped to detect any time delay. Unfortunately, a good watch had not yet been invented. Galileo could not detect any finite speed.

In 1676 Dutch astronomer Ole Roemer finally measured the speed of light. He did so using another Galileo discovery, the moons of Jupiter. By measuring the times when the moons passed in and out of Jupiter’s shadow, he finally found that light has a measurable speed. Since Roemer’s time, many other experiments have been devised to more accurately measure c. Roemer visited Isaac Newton in 1679; this discovery is mentioned in Newton's Principia.

Isaac Newton could imagine cannonballs fired at orbital speed, and calculate that a satellite in a circular orbit would have a certain velocity at a given altitude. Since Newton knew that Moons and apples are both guided by one law, might he have suspected that light is also affected by gravity? Centuries later, Einstein would show that light is indeed affected by gravitation. Light is far too fast to be drawn into orbit around the Earth, but the mass of a Universe would indeed pull light into a circular path.

There has long been speculation of whether the speed of light has always been constant. In 1874, the year after Maxwell published his equations, William Thomson and P.G. Tait claimed to have found a decrease in the speed of light. (W. Thomson, and P.G. Tait, Natural Philosophy, V. 1, p. 403, 1874) Thomson was the 1st Lord Kelvin and a very prominent scientist of the time. J.Q. Stewart in 1931, H.E. Buc in 1932, and P.I. Wold in 1935 also suggested that c changes.

Change in c has been put forward as a cause of cosmological redshifts. This "tired light" explanation has been disfavoured by experiments, but we will see that c does have an affect on redshifts. Barry Setterfield has written an exhaustive study using statistical analysis to claim change in c. More recently John Moffat, Joao Maguiejo and Andreas Albrecht have independently suggested a change in c as a solution to cosmological puzzles. Many, many scientists have speculated that c changes.

In conclusion, anyone can speculate that the speed of light changes, and many people have. For this to be more than the story of a speculation, we need the theory behind c. Why does light travel at 299.792.5 kilometres per second, not faster or slower? What is the principle behind c? NEXT: A Theory that a child could understand.

Tuesday, April 03, 2007

A Few Stood Against Many


"The world will know that free men stood up against a tyrant,
and a few stood against many."

Somehow that line from "300" seems applicable. Hopefully you are also in a place to enjoy the beautiful full Moon this week. This has turned into a busy week using observations to show the speed of light slowing today as predicted. Type Ia supernovae show c slowing at high redshifts. Earth's temperature history shows c slowing at lower redshifts. (For cosmologists, Earth's history covers redshifts up to approximately 0.3) Today's observations show that c is still slowing as we write. No amount of personal attacks can overcome that.

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Monday, April 02, 2007

In Planck Units: M = t


Refer to Kea's blog for a spectacular photo of the "Great Hexagon of Saturn." Again our Cassini spacecraft has discovered something that old science can't explain. As we have seen, there is more going on inside the planet than meets the eye. This includes an immense magnetic field and polar jets of charged particles, exactly as produced by a Black Hole.

The Northern jet is composed of electrons which spiral tightly around the magnetic field lines. The Southern jet is made of heavier ions, which travel around to the North and follow field lines back in. Earth's Van Allen belts work the same way, with concentric lanes of positive and negative particles travelling in opposite directions. At Saturn's North Pole, the incoming positive stream crowds in on the outgoing negative stream. As nature shows us with the honeycomb, the best way to crowd things together is in hexagons.

Our unit systems are mostly based upon some earthly measure, like the distance a man can reach. Physicists often prefer to use a system based upon some fundamental property of nature. This has led some to use units based upon the "constants" h and c. While Planck units provide a universal system of measurement, they are misleading if you think h and c are constant!

Above are the Planck units of length, time, and mass. As readers of the papers know, speed of light c is proportional with t to the -1/3 power. Since most measurements indicate that the product hc is a constant, Planck value h must be inversely proportional with c, t to the 1/3 power. The behaviour of h is similiar to the solution of a random-walk problem. Some of the Planck units are therefore changing.

The Planck length is actually increasing by t to the 2/3 power. Scale R of the Universe, horizon distance, scale of magnetic fields and even the Schwarzhild radius of a Black Hole increase at exactly the same rate. All these radii increase in a way more logical than the humans who struggle to understand it.

The Planck time turns out to be proportional to the observer's time. If you were a tiny cosmologist at time of 10^{-43} seconds, Planck time would still appear to be 10^{60} times smaller. Hopefully by the time the Universe is 13.7 billion years old you will figure this out. Dr. Lieu (who was at the London conference) found experimentally in a paper (ApJ 585, L77) from 2003 that this "Planck time" is an illusion.

Back when I was enjoying The Blue Mountains, someone noticed that "The Equation" in Planck units is just:

M/M_pl = t/t_pl

Mass of the Universe divided by Planck mass is equal to age of the Universe divided by Planck time. Both sides of the equation are now dimensionless numbers, and both are constant.

Using Planck units, you can write this in even simpler form:

M = t

This must be the simplest equation ever! It is amazing that humans haven't figured this one out yet. Personally I prefer not to use Planck units because they can be so misleading.

The "M = t" was noticed recently by a very well-known blogger. I will not give his name, for he has a "bad boy" image to maintain. Though he has a reputation as the biggest skeptic, he has slowly come over to our side. He may be telling the Harvard string theory group that we are on to something. It would be easy to get angry with others, but there is great value in patience.

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