Saturday, October 25, 2008

Moffat Reinventing Gravity

John Moffat began as a struggling artist in Paris, then became interested in physics. At age 20 he wrote a letter to Albert Einstein, and was surprised to receive a reply. They exchanged letters, and Moffatt became the only student at Trinity College to receive a PhD without an undergraduate degree. Sometime in the late 1980's Moffat became interested in a changing speed of light.

In 1992 Moffat submitted a paper to Physical Review D. The referees were outraged and his paper was rejected. In 1993 Moffatt's paper was finally accepted by the International Journal of Modern Physics D. Years later he came across the Albrecht-Maguiejo paper on the speed of light, which was written completely independently. As for precedence, Lord Kelvin claimed a changing c in a paper published in 1875!

In his new book REINVENTING GRAVITY, Moffat discusses everything from the speed of light to extra dimensions. From Chapter 6:

INFLATION AND THE VARIABLE SPEED OF LIGHT [VSL]

Given the chances of inflation happening in the early universe are so slim--and the phenomenon could only come about by extreme fine tuning--the sensible reader might ask: Is inflation actually an improvement over the original big bang model? Is it 40percent better? Or perhaps only 10 percent better? When one considers the problems of inflation in this way, the original motivation for inflation as a solution to the initial conditions of the universe is somewhat diminished...

WILL THE DATA DISCRIMINATE BETWEEN INFLATION AND VSL?

Despite problems and criticisms over the years, inflation has become accepted as a realistic picture of what happened in the very early universe. Why is more attention not paid to VSL, which is an alternative to inflation, solves the horizon and flatness problems, and predicts a scale-invariant spectrum of quantum fluctuations in agreement with experimental data? The answer may be more sociological than scientific. Inflation has been around a dozen years longer than VSL, and it is often easier to support the incumbent and not bother looking very deply into the qualifications of the challenger.

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Wednesday, October 22, 2008

Chandrayaan


Today India's Chandrayaan-1 spacecraft was successfully launched. It will join Japanese and Chinese missions already orbiting the Moon. India is the world's largest democracy and in a few decades will be the world's most populous nation. India's economy is growing rapidly. It is home to many fine scientists and engineers who do not want to be left out. Let us wish them the best of luck. Exploring the Moon is an international effort.

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Tuesday, October 21, 2008

Parallel Lives

Tonight America's PBS network airs the BBC documentary PARALLEL WORLDS, PARALLEL LIVES. Hugh Everett III earned his first degree in Chemical Engineering, then went to Princeton in 1953 to study Game Theory. (In 1950 at Princeton John Nash published his PhD thesis on game theory.) Everett took his first physics course at age 23, Introductory Quantum Mechanics with Robert Dicke. Everett's PhD thesis under John Wheeler, "Theory of the Universal Wave Function," pioneered the many-worlds interpretation of quantum mechanics.

In quantum theory, a particle's state can never be precisely measured or predicted. In Everett's interpretation, these uncertainties produce many alternate worlds, sprouting infinitely like a many-headed tree. He believed that we could be living in just one of countless such alternate realities. In one universe McCain wins the presidency and in another it's Obama! Everett's idea was far ahead of the prevailing physics, and was mostly ignored in its time.

Discouraged by his theory's lack of acceptance, Everett left academia for private industry. He later achieved financial success in the defence industry. In the 1970's the physics world finally took notice. One article appeared in Physics Today in 1970, and another in Analog magazine during 1977. Also in 1977 Wheeler invited Everett to give a talk at University of Texas in Austin, where Everett was treated like a star.

According to the documentary, Everett's life descended into depression and isolation. His death at age 51 was speeded by heavy smoking and drinking. His son Mark Everett is frontman for rock band the Eels. Many physicists today are fascinated by the many-worlds interpretation.

Disclaimer: The writer also came up with unusual ideas while in my twenties, but has not yet descended into smoke or drink. Stories like Everett's are easy to sympathise with. The idea of parallel world causes endless fascination for physics and science fiction.

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Sunday, October 19, 2008

Black Holes Get In Early


Artist's conception of galaxy 4C60.07

The Submillimeter Array atop Mauna Kea consists of eight radio dishes observing as one. The dishes can be moved among 24 different locations to give resolution as great as a single 500 meter dish. It was built as a partnership between the Harvard-Smithsonian zObservatory and the Institute of Astronomy and Astrophysics in Taiwan. New observations here suggest that Supermassive Black Holes were common in early galaxies.

Two such galaxies were observed in a collision 12 billion years in the past. Galaxy 4C60.07 was first observed because of its bright radio emission. The radio signal is one sign of a rapidly spinning Black Hole. The latest observations reveal a previously unknown companion galaxy preventing 4C60.07 from forming stars. At a time when the Universe was less than 2 billion years old, both galaxies contained Supermassive Black Holes. CfA Press Release

Every galaxy ever found contains at its centre an enormous Black Hole. Even The Farthest Galaxies, formed barely 700 million years after the Big Bang contains a singularity. This is far too early for the Black Hole to have formed from stellar collapse. These Black Holes are likely primordial, formed from quantum fluctuations at a time near the Big Bang. Rapid expansion of the Universe grew the Black Holes to their enormous size, which seeded the formation of galaxies. Once primordial Black Holes were thought to be tiny. Their size would be limited by a "horizon distance" related to the speed of light. Discovery of primordial Supermassive Black Holes is one more sign of "c change" in physics.

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Friday, October 17, 2008

One Hot Planet

Astonomers have now discovered many "hot Jupiters," gas giants orbiting very close to their sun. On May 9, 2007 Hot Gas reported object HC 149206b orbiting its star in 2.877 days with a surface temperature of 2040 degrees Celsius. On August 7, 2007 Milkshake Planets reported that TrES-4 has 1/3 the density of liquid water but a surface temperature of 2300 degrees!

This week the UK Wide Area Search for Planets has found WASP 12-b by occultation of a star 800 light-years away. The planet is 50 percent more massive than Jupiter, and orbits in only 1.1 days! The temperature of WASP 12-b is calculated to be 2250 degrees Celsius. How such worlds can exist without boiling away is a challenge to theories of planet formation.

If giant planets formed around singularities, presence of the Black Hole would stabilise their structure and prevent them from evaporating. Since the time of Laplace, astronomers have theorised that planets somehow condensed from rotating clouds of gas. In such a nebula, tiny Black Holes would have seeded planetary formation. In the case of Jupiter, an internal singularity would explain both internal heat and magnetic field. The interiors of gas giants are excellent places to seek Black Holes.

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Tuesday, October 14, 2008

Massive and Dark

On September 24 a mysterious Dark Flow was reported. Clusters of galaxies are being drawn toward an immense unseen mass. These could be ultra-massive Big Gulp Black Holes, far more massive than anything astronomers have imagined. This was predicted by the blog back in October 2006, Stirring Things Up.

"Expansion of the Universe is not uniform. Individual motions of galaxies can oppose the Hubble flow, like trout swimming upstream. The Milky Way and thousands of other galaxies are falling at 600 km/sec toward an unseen mass called the Great Attractor. This object has the mass of 10^16 Suns or 100,000 galaxies! It may be a true Black Hole, so monstrously massive that nothing can escape. There is evidence of another Great Attractor some 700 million years away.

"These monsters could be common, yet they are not counted in mass surveys. The missing 2/3 ascribed to "dark energy" may be hidden from us. It is foolish to think that humans know all that is out there. That is like Wile E. Coyote, Super Genius not realising that he is falling into an abyss."

Today another research group led by Mike Hudson from University of Waterloo reports that our region of the Universe is not expanding uniformly. One half of the sky appears to be expanding faster than the other half. Researchers conclude that massive, unseen structures exist in the Universe. These great attractors would not lie outside the Universe, but beyond our local group of galaxies. This will require revisions of the tired old cosmological model. UPDATE: Preprint of the new paper is entitled Consistently Large Flows on Scales of 100 Mpc/h: A Challenge for the Standard LCDM Cosmology.

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Monday, October 13, 2008

The Economist on Science


Christmas tree lighting at Rockefeller Center.

For Carl, Kea, Matti, Tony and all others who have trouble getting published: Take a break from the journals and read this week's (Oct 11, 2008) issue of THE ECONOMIST. Amid discouraging news about the world economy is a fascinating article Publish and Be Wrong. Speculation about strings, extra dimensions, "dark energy" and even alternate universes fill the journals. According to a group led by Dr. John Ioannidis, the most widely reported scientific papers are most likely to be wrong!

"With so many scientific papers chasing so few pages in the most prestigious journals, the winners could be the ones most likely to oversell themselves—to trumpet dramatic or important results that later turn out to be false. This would produce a distorted picture of scientific knowledge, with less dramatic (but more accurate) results either relegated to obscure journals or left unpublished...

"Dr Ioannidis made a splash three years ago by arguing, quite convincingly, that most published scientific research is wrong. Now, along with Neal Young of the National Institutes of Health in Maryland and Omar Al-Ubaydli, an economist at George Mason University in Fairfax, Virginia, he suggests why...

"The group’s more general argument is that scientific research is so difficult—the sample sizes must be big and the analysis rigorous—that most research may end up being wrong. And the “hotter” the field, the greater the competition is and the more likely it is that published research in top journals could be wrong..."

We can see this phenomenon in most physics journals. The "hot" fields of speculation spawn hordes of papers. When the Sun and planets were thought to circle Earth, theories were proposed with 60-100 epicycles. In the case of "dark energy," a divergence of theories have been proposed, nearly all of which must be wrong. Because of a "hot" subject, these papers get published in all their wrongness.

The Ioannidis group's results are published in "Public Library of Science Medicine," an online journal. Today papers that suggest a changing speed of light have great difficulty being published. Real advances in science occur out of the press spotlight. THE ECONOMIST concludes, "The question for Dr Ioannidis is that now his latest work has been accepted by a journal, is that reason to doubt it?"

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Sunday, October 12, 2008

Hooray for Bad Astronomy

Comments have been sparse lately, but yet another discussion thread has appeared on the Bad Astronomy/Universe Today forum. Non-members can not leave comments there, but let us hope that this and other discussions stay civil.

To answer one question: "von Riemann" is a pun in German, meaning that the theory is from Riemann. If Riemann has his own Universe, he deserves "von" in front of his name.

Here's a fun question: How much potential energy does your pen have? In physics class we learn Newton's formula:

Eu = -GMm/r

Where Eu is potential energy, M is the mass of a larger object, usually Earth. m is the pen's mass, and r is the distance between masses.

Usually we measure the pen's energy from Earth, but the pen has more potential from the Sun. The pen doesn't fall toward the Sun because it shares Earth's orbital velocity. The pen has even more potential from the galaxy and everything else in the Universe. The pen's true potential should be:

Eu = -$\Sigma$ GMm/r

The $\Sigma$ sums the potential from every other mass in the Universe! How do we solve this? Fortunately, on large scales the Universe is a spherical mass distribution. We can write:

Eu = -GMm/R

Here M is total mass of the Universe, and R is distance to the centre of that mass.

There is no centre in Space, for every bit resembles every other bit. There is a centre in time, what we call a "Big Bang." Near that centre, mass M occupied a tiny volume. Now these things are known:

R = ct

GM = tc^3

Eu = -GMm/R = -(tc^3)m/(ct)

Eu = -mc^2

Does anyone doubt this E = mc^2 business? When it was first written in 1905, few paid attention. A century later everyone has heard of this equation, even if they don't understand it.

To avoid confusion, we will call E the Einstein energy and rename Eu as U, the Newton energy:

E + U = 0

The total energy of the pen is just zero! That applies for any object, from the tiniest particle to the biggest Black Hole. The total energy of the Universe is zero! It's the ultimate free lunch, which has allowed it to evolve from a tiny point to the immensity we observe today.

Best wishes to Praedst and other contributors. Followers on the Bad Astronomy/Universe Today are welcome to leave their questions here.

UPDATE: Following Ethan's lead, they seem to have become stuck on the Oklo Reactor. Oklo did not measure c, but the fine-structure constant proportional to product hc. This product is also part of the photon energy hc/$\lambda$ and the Chandrasekhar mass. If c decreases with time, h must increase inversely. They may be about to miss the chance of linking quantum mechanics with Relativity and gaining scientific immortality. This has been dealt with before, see Constraining Theories of the Speed of Light.

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Saturday, October 11, 2008

Jim Benson 1945 - 2008



The writer last met Jim Benson in 2007. He was very upbeat about the future in Space, and took great interest in the Spacesuit. He had big plans for his Benson Space Company, starting with suporbital flights in the Dreamchaser craft. Shortly afterward he was diagnosed with serious health problems. He wil be sorely missed.

Jim began by studying geology, then invented full text computer indexing and searching. He founded multiple companies like Compusearch. HIs Spacedev company was also successful, building and contributing to many spacecraft projects. As much as any party, Spacedev was responsible for the success of Spaceship One in 2004.

The heart of any rocket is the powerplant, and SS1 was powered by a hybrid engine. Scaled Composites had never built a rocket, so building and fuelling the engine was subcontracted to Spacedev. After the X-Prize was won and Scaled got most of the credit, the two companies parted ways. A fuel explosion at Scaled in 2007 tool the lives of three engineers. Recently the two companies have come back together to build Spaceship Two.

Among Jim's visions was a privately funded voyage to the Moon. Its mission would be servicing a Lunar Observatory. The trip is estimated to cost 3 billion, a tiny fraction of what NASA would spend. In 2007 he showed this fascinating video. 4 astronauts descend to the Moon in Lunar Human Access (ALOHA) chairs. That incredible ride would require a better Spacesuit, which led to Jim's interest. The dream of reaching the Moon must now continue.

Check out the new Carnival of Space!

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Thursday, October 09, 2008

Enceladus Near-Miss



On October 9 Cassini passes within 25 km of Enceladus! This moon was subject of one of this blog's earliest posts on June 2006, Here Be Dragons.

"In 2005 our Cassini spacecraft made some amazing discoveries about Saturn and her moons. The moon Enceladus has a volcanic "hot spot" centred on its South Pole. The pole, which should be the coldest region on the moon, is the hottest! This spot emits an enormous plume of vapour which maintains Saturn's E Ring. Old theories of radioactive decay or tidal stress can not explain this hot spot.

"Enceladus' core and behaviour can be modelled with a central singularity of 10^12 kg. This mass is typical for a primordial singularity. This object consumes only 2.8 kg per year and generates 10^9 watts of radiation. Water and other molecules near this centre are heated to a plasma. Electrons are stripped from atoms, and the resulting ions are drawn into circular orbits. The resulting current generates a magnetic field with the 'positive' pole in the South.

"Electrons and positively charged ions spiral along magnetic field lines to form bipolar jets, the classic sign of a singularity. The Northern jet is composed of electrons which are absorbed by the moon's interior. More energetic ions of the Southern jet penetrate these layers to warm the South Pole. Escaping ions spiral into space, exactly as observed by Cassini.

"Unless Saturn's Rings are replenished, they would decay within 100 million years. Then we would face the anthropic question of why they exist in the right time for humans to view them. Thanks to the Cassini spacecraft, we have witnessed the E Ring being resuppllied from a moon. This observation suggests that similiar processes maintain the rings indefinitely."

Last December at the AGU Meeting, scientist Jennifer Meyer pointed out that tidal forces could not account of Enceladus' heat. Last month in Heavy Rings we learned that Saturn's Rings are heavier and longer-lived than previously thought, exactly as predicted. Scientists have long wondered about the origin of planet's internal heat and magnetic fields. A Black Hole within Enceladus has applications for many worlds, including Earth.

Check out the new Carnival of Space!

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Tuesday, October 07, 2008

Nambu, Kobayashi and Maskawa

The Nobel Prize in physics has been awarded to Youchiro Nambu, Makoto Kobayashi and Toshihide Maskawa. Nambu fomulated a mathematical description of spontaneous broken symnetry. Kobayashi and Maskawa explained broken symnetry in terms of the standard model, but required that the model be extended to three families of quarks. The new quarks were predicted in 1972, but were confirmed only in recent years. In 2001 both BABAR and BELLE experiments detected broken symnetries exactly as predicted by Kobayashi and Maskawa. As with a changing speed of light, the most far-reaching predictions take a long time to be proved.

Dr. Jerome Corsi was detained by immigration authorities in Kenya. After doing research there, Corsi was on his way to a press conference. Is Kenya threatened by illegal immigrants from the US? Corsi broke now laws, committed no crime other than finding something the authorities didn't like. In today's security regime, researchers and scientists come under particular scrutiny. The Nobel Prize shows that science is an international effort. The world is rapidly becoming dangerous for researchers.

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Monday, October 06, 2008

Mercury Flyby 2


Today the MESSENGER spacecraft is due to make its second flyby of Mercury. In 2011 the probe will finally settle into orbit. The innermost planet has been known to have a magnetic field since the Mariner 10 flyby of 1977. MESSENGER's first flyby confirmed the prediction of vulcanism, indicating an internal heat source. To explain the magnetic field, scientists have inferred an iron-rich core, as with Earth. Though the planet's volcanic surface is full of materiel erupted from within, none of the volcanic plains show traces of iron. An iron core is solely an inferrence, with no direct evidence. Something else may be causing internal heat and a magnetic field. Mercury's centre would be a good place to seek a Black Hole.

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Thursday, October 02, 2008

Zoom Into NGC 3324


From the Hubble Space Telescope, currently out of action. The star-forming nebula NGC 3324, in one corner of the Carina Nebula. The Nebula also contains the Keyhole Nebula and the tumultuous star Eta Carina. Pillars of gas are stars being born, possibly seeded by tiny Black Holes.

Alice's Astro hosts the new Carnival of Space!

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Wednesday, October 01, 2008

Young With Magnetic Personality


In July this blog reported on Magnetic Galaxies formed early in the Universe's history (photo above.) Now astronomers have found that a galaxy formed 6.5 billion years ago has a magnetic field 10 times stronger than our Milky Way. As before, the discovery was made using radio astronomy. The world's biggest steerable radio telescope in Green Bank (West Virginia) directly measured the field of protogalaxy DLA-3C286. The results appear in the October 2 issue of NATURE.

These discoveries challenge old theories of galaxy formation. Every galaxy ever examined contains at its centre a supermassive Black Hole. This singularity's rotation causes huge magnetic fields to form in its vicinity. If the field billions of years ago was this strong, the Black Hole must have already been large. Rather than growing along with the galaxy, the Black Hole was supermassive from the start.

More and more evidence indicates that supermassive Black Holes are primordial, formed from quantum fluctuations grown huge by expansion of the Universe. Size of a PBH is limited by a horizon distance within light's reach. Previously scientists thought that Primordial Black Holes were tiny. Supermassive Black Holes within galaxies, including ours, are more indicators of a changing speed of light.

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