Thursday, August 31, 2006

Going Supernova 3Dgif


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Modeling the collapse of a massive star represents one of the greatest challenges in computational physics. All four fundamental forces of nature are in play, giving us a cosmic laboratory with conditions unlike anywhere else in the Universe. Only if we truly understand the fundamental physics involved and do a perfect job of implementing the computational algorithms will we be able to reproduce the ever-increasing quality of the observational data.

It focuses on the deaths of aged stars in supernova explosions, which are among the most violent events in nature, unleashing power that can briefly outshine a galaxy of 100 billion stars. When a supernova explodes, it blasts oxygen, carbon and other vital chemical elements through space and creates heavier elements like copper and nickel.

Unlike Type I supernovae, which are powered by a thermonuclear explosion of a white dwarf star, Type II supernovae, the more frequently occurring type modeled by Warren and Fryer, are powered by the massive star's gravitational collapse. The star begins its life burning hydrogen, then heavier elements as the hydrogen is exhausted and the temperature rises. Eventually, the core of the star consists entirely of iron, which can no longer provide the energy to resist the enormous gravitational forces pushing down on it.

As the iron atoms are crushed together, the core temperature rises to more than 10 billion degrees. The force of gravity overcomes the repulsive force between the nuclei and, in a few tenths of a second, the core of the star collapses from its original size of about one-half the diameter of Earth to 100 kilometers. The core heats the material surrounding it not with light, but by radiating most of its energy in neutrinos, nearly massless sub-atomic particles that can pass through tons of matter without being affected. As the in-falling gas approaches the core, it is exposed to a higher and higher flux of neutrinos. A tiny fraction of those neutrinos are absorbed. They heat the gas, which expands and becomes buoyant.

The heated gas floats upward in large bubbles carrying energy away from the core and is replaced by colder gas that sinks toward the core and in turn becomes heated. This heat transfer from the core to the envelope of the star results in enough energy transfer to create an explosion.

"With these three-dimensional results, we have reached the final battleground and are ready to attack the more exotic problems that involve rotation and non-symmetric accretion."

los alamos news/releases 4 June 2002

LOS ALAMOS, N.M., June 4, 2002 -- Astrophysicists from Los Alamos National Laboratory, New Mexico, created the first 3-D computer simulations of the spectacular explosion that marks the death of a massive star. Presented to the American Astronomical Society meeting in Albuquerque, N.M., the research by Michael Warren and Chris Fryer eliminates some of the doubts about earlier 2-D modeling and paves the way for rapid advances on other, more exotic questions about supernovae.

The work of Warren and Fryer is part of a larger Supernova Science Center effort, which includes scientists from the University of Arizona, the University of California Santa Cruz and Lawrence Livermore National Laboratory. The Supernova Science Center is funded by the Department of Energy's Office of Science, Scientific Discovery Through Advanced Computing program.
More information is available at www.supersci.org.

Other groups, including the Terascale Supernova Initiative headed by Anthony Mezzacappa at Oak Ridge National Laboratory and the group led by Thomas Janka at the Max Planck Institute for Astrophysics in Germany, are also making rapid progress in the area of core-collapse supernovae.

Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration (NNSA) of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore national laboratories to support NNSA in its mission.

Los Alamos enhances global security by ensuring the safety and reliability of the U.S. nuclear weapons stockpile, developing technical solutions to reduce the threat of weapons of mass destruction and solving problems related to energy, environment, infrastructure, health and national security concerns..


Images available online los alamos national laboratories
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SciDac Supernova Science Centre
Are-we-made-of-stardust by Plato
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If you obey all the rules you miss all the fun.
Katharine Hepburn more Famous Quotes
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Wednesday, August 30, 2006

G-Waves closer


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NASA scientists have reached a breakthrough in computer modeling that allows them to simulate what gravitational waves from merging black holes look like. The three-dimensional simulations, the largest astrophysical calculations ever performed on a NASA supercomputer, provide the foundation to explore the universe in an entirely new way.

According to Einstein's math, when two massive black holes merge, all of space jiggles like a bowl of Jell-O as gravitational waves race out from the collision at light speed.

"These mergers are by far the most powerful events occurring in the universe, with each one generating more energy than all of the stars in the universe combined. Now we have realistic simulations to guide gravitational wave detectors coming online," said Joan Centrella, head of the Gravitational Astrophysics Laboratory at Goddard.

The simulations were performed on the Columbia supercomputer at NASA's Ames Research Center near Mountain View, Calif. This work appears in the March 26 issue of Physical Review Letters and will appear in an upcoming issue of Physical Review D. The lead author is John Baker of Goddard.Similar to ripples on a pond, gravitational waves are ripples in space and time, a four-dimensional concept that Einstein called spacetime. They haven't yet been directly detected.

Gravitational waves
Gravitational waves hardly interact with matter and thus can penetrate the dust and gas that blocks our view of black holes and other objects. They offer a new window to explore the universe and provide a precise test for Einstein's theory of general relativity.

The National Science Foundation's ground-based Laser Interferometer Gravitational-Wave Observatory and the proposed Laser Interferometer Space Antenna, a joint NASA - European Space Agency project, hope to detect these subtle waves, which would alter the shape of a human from head to toe by far less than the width of an atom.

Black hole mergers
Black hole mergers produce copious gravitational waves, sometimes for years, as the black holes approach each other and collide. Black holes are regions where gravity is so extreme that nothing, not even light, can escape their pull. They alter spacetime. Therein lies the difficulty in creating black hole models: space and time shift, density becomes infinite and time can come to a standstill. Such variables cause computer simulations to crash.


Left image: Scientists are watching two supermassive black holes spiral towards each other near the center of a galaxy cluster named Abell 400. Shown in this X-ray/radio composite image are the multi-million degree radio jets emanating from the black holes.

Click enlarge image to view large resolution.
Credit: X-ray: NASA/CXC/AIfA/D.Hudson & T.Reiprich et al.;


These massive, colliding objects produce gravitational waves of differing wavelengths and strengths, depending on the masses involved. The Goddard team has perfected the simulation of merging, equal-mass, non-spinning black holes starting at various positions corresponding to the last two to five orbits before their merger.

With each simulation run, regardless of the starting point, the black holes orbited stably and produced identical waveforms during the collision and its aftermath. This unprecedented combination of stability and reproducibility assured the scientists that the simulations were true to Einstein's equations.

The team has since moved on to simulating mergers of non-equal-mass black holes.

Einstein's theory of general relativity employs a type of mathematics called tensor calculus, which cannot be turned into computer instructions easily. The equations need to be translated, which greatly expands them. The simplest tensor calculus equations require thousands of lines of computer code. The expansions, called formulations, can be written in many ways. Through mathematical intuition, the Goddard team found the appropriate formulations that led to suitable simulations.

Progress also has been made independently by several groups, including researchers at the Center for Gravitational Wave Astronomy at the University of Texas, Brownsville, which is supported by the NASA Minority University Research and Education Program.

As of November 2005, LIGO is up and running and could, in theory, detect gravitational waves from stellar-size black hole mergers any day. LISA, in the planning stages, could detect longer-wavelength gravitational radiation from supermassive black holes. The beauty of the NASA simulations is that they can be scaled to fit either scenario.

Breakthrough In Black Hole Simulation NASA News Release 18 april 2006
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NASA High Resolution G-Wave Images:
high res image 1
high res image 2
high res image 3
high res image 4
high resolution Image 5
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Numerical Relativity and Math Transference by Plato
Gravitational n-bodies by Sean Carroll @ Cosmic Variance
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Monday, August 28, 2006

G-Waves 3Dsim


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Gravitational waves 3D Simulations

Simulations on a supercomputer have allowed Nasa scientists to understand finally the pattern of gravitational waves produced by merging black holes. The work should help the worldwide effort that is currently underway to make the first detection of these "ripples" in the fabric of space-time. Ultra-sensitive equipment set up in the US and Europe is expected to achieve the breakthrough observation very soon.

The new research will make it easier to recognise the correct signals.

"With these calculations, we are now able to know what will be the distinctive gravitational wave signature that comes out from just outside merging black holes," commented Professor Peter Saulson, who is part of the Laser Interferometer Gravitational Wave Observatory (Ligo) Scientific Collaboration.
"And by looking for this signal, we will be able to learn whether Einstein's Theory of General Relativity is correct or whether there is even stranger physics ahead for us in the future."

Tell-tale sign
Researchers believe their first detection of gravitational waves is imminent. Confirmation would be regarded as a major scientific advance, and would usher in a new way of studying the Universe. Any accelerating object should send these waves of energy radiating outwards at the speed of light; but only truly massive bodies, such as exploding stars and coalescing black holes, would disturb space-time sufficiently for our technology to pick up the signal.


Gravitational wave hunt

Laser interferometers bounce light beams back and forth down long tunnels
Passing gravitational waves should produce small disturbances in the light arms
The set-ups are sensitive to deviations that are fractions of the width of a proton
Different events, such as merging black holes, should have a unique signature
Scientists hope eventually to launch space-based laser interferometers


Observatories - such as Ligo, based in Louisiana and Washington states, and GEO 600 in Germany - bounce lasers down long tunnels, hoping to pick up the fantastically small disturbances the waves should generate as they pass through the Earth.

New 3D Simulations
The new simulations, performed on the US space agency's Columbia supercomputer at the Ames Research Center in California, give the wave hunters a clear profile to look for in their data. Nasa astrophysicist Joan Centrella described the simulation results as the "fingerprint" that would betray the existence of gravitational waves. "To get this fingerprint, we have simulated the merger of two black holes by translating Einstein's equations into a way that computers can understand them.

This has been a 'Holy Grail' quest for the last 30 years"

Previous efforts to model black hole mergers had "crashed and burned"
Black holes - extreme regions of space where even light cannot escape the pull of gravity - were so exotic that computers had enormous difficulty grappling with the calculations involved.

Columbia used new formulations of Einstein's calculations
Riding on gravitational waves But Columbia's enormous power has finally cracked the problem. The 3D simulations used more than 2,000 of the machine's 10,000 64-bit processors, running over a period of 80 hours.

They modelled the merging of equal-mass, non-spinning black holes, starting at various positions corresponding to the last two to five orbits before the holes fell on to each other.
With each simulation run, regardless of the starting point, the black holes orbited stably and produced identical waveforms during the collision and its aftermath.
This unprecedented combination of stability and reproducibility assured the scientists that the simulations were true to Einstein's equations, Nasa said in a statement.

The results apply both to the smaller black holes created when giant stars collapse and the supermassive black holes that observations show lurk at the centres of galaxies. Right now, Ligo is searching the sky. It can see the stellar-mass version of these calculations - two black holes about the mass of the Sun out to about 150 million light-years away, a distance that includes several thousand galaxies.


Gravitational wave goals

Laser interferometers are being constructed across the world
The installations will see into the cores of exploding stars
They will make it possible to trace the outline of black holes
Space observatories will probe the first moments of creation
The new knowledge may lead to a unified theory of physics

"The Ligo collaboration is searching through the data for this and other signals, and for all we know one of those events could go off tomorrow."

And Professor Jim Hough, from the University of Glasgow, UK, commented: "Centrella's work is superb. This is the first time there have been really good simulations for when the gravitational field is so strong. This is terribly useful because it means 'templates' can be developed for data analysis in the signals picked up by our detectors."

Unlike electromagnetic waves - the light seen by traditional telescopes - gravitational waves are extremely weak. If one were to pass through your body it would alternately stretch your space in one dimension while squashing it in another; but the changes are tiny.

Laser interferometers are looking for disturbances in their experimental set-ups that are equivalent to mere fractions of the diameter of a proton, one of the particles that make up the nucleus of an atom.
If the technology can be made to work effectively, it will allow scientists to probe the Universe in a way that is not dependent on light, and should, theoretically, allow them to look right back to the first moments after the Big Bang.

Original Text BBC News 19 april 2006

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Beyond Spacetime by Plato
hep th papers on blackholes by Lubos Motl @ Reference Frame
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When shall we know computers have developed free will
when they question the existence of the programmer
- Quasar9
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Sunday, August 27, 2006

Universe of Pearls


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Universe of Pearls courtesy of cyberchaos @ flickr


Today I'm diving & searching for Pearls of Wisdom
If you've any beauties that were handed down to you
from generation to generation by your grandmothers
or from others you have encountered along the way
Please kindly share them in the comments section.

Thank you! - Q.
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Quote of the day:
It is the soothing thing about history that it does repeat itself.
Gertrude Stein more Famous Quotes
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Saturday, August 26, 2006

Mystic Triangle


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There is a Truth that no man can deny
there is that which is greater than man!

There is a Truth that no man can deny
there is essence which gives life to man!

Wishing you All a most peaceful weekend - Q.
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Friday, August 25, 2006

Gravitational Mirage


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Simulated gravitional lensing

A gravitational lens is formed when the light from a very distant, bright source (such as a Quasar) is "bent" around a massive object (such as a massive galaxy) between the source object and the observer. The process is known as gravitational lensing, and is one of the predictions of Albert Einstein's general relativity theory. It is sometimes known as the Einstein effect, although that is not the only meaning attributed to that term.

Above is a simulation of gravitational lensing caused by a Schwarzschild black hole going past a background galaxy. A secondary image of the galaxy can be seen within the black hole's Einstein ring on the side opposite the galaxy. The secondary image grows (remaining within the Einstein ring) as the primary image approaches the black hole. The surface brightness of the two images remains constant, but their angular sizes vary, hence producing an amplification of the galaxy luminosity as seen by a distant observer. Maximum amplification occurs when the galaxy (or in this case a bright part of it) is exactly behind the black hole.


Gravitational lensing

In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

In addition to the Chandra observation, the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope and the Magellan optical telescopes were used to determine the location of the mass in the clusters.

This was done by measuring the effect of gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein's theory of general relativity.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required.

NASA RELEASE: 06-297 CHANDRA reveals Dark Matter
More Amazing photos from Chandra news @ NASA Marshall Centre
More on
CHANDRA press Release by Sean Carroll @ Cosmic Variance


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Bending light around a massive object from a distant source.
The orange arrows show the apparent position of the background source.

The white arrows show the path of the light from the true position of the source

Description
In a gravitational lens, the gravity from the massive object bends light like a lens. As a result, the path of the light from the source is curved, distorting its image, and the apparent location of the source may be different from its actual position. In addition, the observer may see multiple images of a single source. If the source, massive object, and the observer lie on a straight line, the source will appear as a ring behind the massive object. This phenomenon was first mentioned by Chwolson in 1925, and quantified by Einstein in 1936. It is usually referred to in the literature as an Einstein ring, since Chwolson did not concern himself with the flux or radius of the ring image. More commonly, the massive galaxy is off-center, creating a number of images according to the relative positions of the source, lens, and observer, and the shape of the gravitational well of the lensing galaxy.

There are three classes of gravitational lensing:
Strong lensing:
where there are easily visible distortions such as the formation of Einstein rings, arcs, and multiple images.
Weak lensing: where the distortions of background objects are much smaller and can only be detected by analysing large numbers of objects to find distortions of only a few percent.
Microlensing: where no distortion in shape can be seen but the amount of light received from a background object changes in time. Typically, both the background source and the lens are stars in the Milky Way.

The effect is weak, such that (in the case of strong lensing) a galaxy having a mass of over 100 billion solar masses will produce multiple images separated by only a few arcseconds. Galaxy clusters can produce separations of several arcminutes. In both cases the galaxies and sources are quite distant, many hundreds of megaparsecs away from our Galaxy.
Gravitational lenses act equally on all kinds of electromagnetic radiation, not just visible light. Weak lensing effects are being studied for the cosmic microwave background as well galaxy surveys. Strong lenses have been observed in radio and x-ray regimes as well. If a strong lens produces multiple images, there will be a relative time delay between two paths: that is, in one image the lensed object will be observed before the other image.


History
According to general relativity, mass "warps" space-time to create gravitational fields and therefore bend light as a result. This theory was confirmed in 1919 during a solar eclipse, when Arthur Eddington observed the light from stars passing close to the sun was slightly bent, so that stars appeared slightly out of position.

Einstein realized that it was also possible for astronomical objects to bend light, and that under the correct conditions, one would observe multiple images of a single source, called a gravitational lens or sometimes a gravitational mirage. However, as he only considered gravitational lensing by single stars, he concluded that the phenomenon would most likely remain unobserved for foreseeable future. In 1937, Fritz Zwicky first considered the case where a galaxy could act as a lens, something that according to his calculations should be well within the reach of observations.

It was not until 1979 that the first gravitational lens would be discovered. It became known as the "Twin Quasar" since it initially looked like two identical quasars; it is officially named Q0957+561. This gravitational lens was discovered accidentally by Dennis Walsh, Bob Carswell, and Ray Weymann using the Kitt Peak National Observatory 2.1 meter telescope.

The study of gravitational lenses is an important part of the future of astronomy and astrophysics.

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The essence of who we are and what defines us is our soul,
the divinity that resides inside each one of us.
Serenity's Tide
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Wednesday, August 23, 2006

New Dimensions at LHC


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Picture courtesy of cyberchaos @ flickr

CERN's new LHC collider
aims to find the long-awaited "Higgs particle", which endows other particles with mass. In an entirely new energy range and with its special experimental conditions, the LHC could also discover other new physics effects.

Why is gravity so weak?
The traditional answer is because the fundamental scale of the gravitational interaction (i.e. the energy at which gravitational effects become comparable to the other forces) is up at the Planck scale of around 1019 GeV - far higher than the other forces.

However, that only raises another question: what is the origin of this huge disparity between the fundamental scale of gravity and the scale of the other interactions?

A possible explanation currently gaining ground in theoretical circles is that the fundamental scale of gravity is not really up at the Planck scale, it just seems that way. According to this school of thought, what is actually happening is that gravity, uniquely among the forces, acts in extra dimensions.

This means that much of the gravitational flux is invisible to us locked into our three dimensions of space and one of time.

Consider, by analogy, what two-dimensional flatlanders would make of three-dimensional electromagnetism. To them, the flux lines of the force between two charges would appear to travel in their planar world, whereas in reality we know that most of the flux lines would spread out through a third dimension, thus weakening the force between the two charges. The initial spreading of the flux lines into the third dimension does have a significant effect: the force appears weaker to a flatlander than is fundamentally the case, just as gravity appears weak to us.

Turning back to gravity, the extra-dimensions model stems from theoretical research into (mem)brane theories, the multidimensional successors to string theories (April 1999 p13).

One remarkable property of these models is that they show that it is quite natural and consistent for electromagnetism, the weak force and the inter-quark force to be confined to a brane while gravity acts in a larger number of spatial dimensions.
The requirement of correctly reproducing Newton's constant, G, at long distances leads to the size of the extra dimensions in which gravity is free to act being related to the number of extra dimensions. If there is just one extra dimension, then the model says that it should be of the order 1013 m, in which case solar system dynamics would be radically different and we would be taught a Newton's 1/r3 law in school rather than the 1/r2 law that we know and love.

So one extra dimension doesn't work. With two extra dimensions, the scale drops to slightly less than 1 mm and, small though that is, it at first seems surprising that extra dimensions of that size have not already been seen. However, because the extra dimensions only affect gravity, the most direct constraints come from experiments to measure G at short distances, and delving into the historical literature on the subject reveals that no measurements of G at the submillimetre scale have ever been made.

A team led by Aharon Kapitulnik at Stanford is currently in the process of accurately measuring G at submillimetre scales for the first time using a tabletop experiment. For more than two extra dimensions their size begins to get quite small: 1 fm, for example, for six extra dimensions, outside the range of even the improved submillimetre gravity experiments. Nevertheless, the model still makes a number of dramatic predictions.

If gravity does have extra dimensions at its disposal, they should manifest themselves at CERN's LHC proton collider, no matter what the number of extra dimensions might be. This is because the fundamental scale of the gravitational interaction should be around a few tera-electron volts, so, at TeV energies, gravitational effects will become comparable to electroweak effects.

Consequently, gravitons will be produced as copiously as photons, with the difference that the photons will remain in our familiar dimensions while many of the gravitons will escape into extra dimensions, carrying energy with them.

More dramatically still, the LHC could produce fundamental string relations of our familiar particles, such as higher-spin relatives of electrons or photons. There is also a possibility that, owing to the now much stronger gravitational interactions, microscopically tiny black holes could be produced with striking signals.

Fortunately, such small black holes are not at all dangerous, being much more similar to exotic particles than large astrophysical black holes, and they decay quite quickly as a result of Hawking radiation. With the recent outburst of ideas in these directions, it is clear that extraordinary discoveries at the LHC may be just around the (extra-dimensional) corner.

Original text from CERN Courier
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Dimensions
locating a point on a plane (ie. a city on a map of the Earth) requires two parameters — latitude and longitude. The corresponding space has therefore two dimensions, its dimension is two, and this space is said to be 2-dimensional (2D). Locating the exact position of an aircraft in flight (relative to the Earth) requires another dimension (altitude), hence the position of the aircraft can be rendered in a three-dimensional space (3D).
If time is added as a 3rd or 4th dimension (to a 2D or 3D space, respectively), then the aircraft's estimated "speed" may be calculated from a comparison between the times associated with any two positions. For common uses, simply using "speed" (as a dimension) is a useful way of condensing (or translating) the more abstract time dimension, even if "speed" is not a dimension, but rather a calculation based on two dimensions. Adding the three Euler angles, for a total 6 dimensions, allows the current degrees of freedomorientation and trajectory —of the aircraft to be known.

Five dimensions
Kaluza-Klein theory
Fifth dimension
Ten, eleven or twenty-six dimensions
String theory
M-theory
Why 10 dimensions?
Calabi-Yau spaces
Infinitely many dimensions
Hilbert space
Special relativity
General relativity
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Laval nozzle and blackholes by Plato
Universe lifecycles from NASA gov
More about Extra Dimensions by Sabine Hossenfelder
Minimal length model by Sabine Hossenfelder

A special thank you to Cynthia for her supra-dimensional
thinking, dancing and boundless inspiration & energy.
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Quote of the Day: No One is a failure who is enjoying life.
William Feather more Famous Quotes
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Tuesday, August 22, 2006

Gravitons & Symmetry


The world can only
be grasped by action,
not by contemplation.
Jacob Bronowski

Without contemplation
how can you know
or enjoy what you
have grasped Quasar9
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Picture Symmetry by cyberchaos @ flickr

Gravitons

In physics, the graviton is a hypothetical elementary particle that transmits the force of gravity in the framework of quantum field theory. If it exists, the graviton must be massless (because the gravitational force has unlimited range) and must have a spin of 2 (because gravity is a second-rank tensor field).

Gravitons are postulated because of the great success of the quantum field theory (in particular, the Standard Model) at modeling the behavior of all other forces of nature with similar particles: electromagnetism with the photon, the strong interaction with the gluons, and the weak interaction with the W and Z bosons. In this framework, the gravitational interaction is mediated by gravitons, instead of being described in terms of curved spacetime like in general relativity. In the classical limit, both approaches give identical results.

However, attempts to extend the Standard Model with gravitons run into serious theoretical difficulties at high energies (processes with energies close or above the Planck scale) because of infinities arising due to quantum effects (in technical terms, gravitation is nonrenormalizable.) Some proposed theories of quantum gravity (in particular, string theory) address this issue. In string theory, gravitons (as well as the other particles) are states of strings rather than point particles, and then the infinities do not appear, while the low-energy behavior can still be approximated by a quantum field theory of point particles. In that case, the description in terms of gravitons serves as a low-energy effective theory.
Since gravity is very weak, there is little hope of detecting single gravitons experimentally in the foreseeable future.

Gravitons & experiments

Detecting a graviton, if it exists, would prove rather problematic. Because the gravitational force is so incredibly weak, as of today, physicists are not even able to directly verify the existence of gravitational waves, as predicted by general relativity. (Many people are surprised to learn that gravity is the weakest force. The dominance of gravity at large scales is due to the fact that the nuclear forces have a limited range, and the electromagnetic force often largely cancels due to the existence of positive and negative charges. In contrast, gravitational charge -- i.e., mass -- is positive or zero for all known forms of matter.)

Gravitational waves may be viewed as coherent states of many gravitons, much like the electromagnetic waves are coherent states of photons. Projects that should find the gravitational waves, such as LIGO and VIRGO, are just getting started.

Is gravity like other forces?

Some question the analogy which motivates the introduction of the graviton. Unlike the other forces, gravitation plays a special role in general relativity in defining the spacetime in which events take place. Because it does not depend on a particular spacetime background, general relativity is said to be background independent. In contrast, the Standard Model is not background independent. In other words, general relativity and the standard model are incompatible. A theory of quantum gravity is needed in order to reconcile these differences.

Whether this theory should itself be background independent, or whether the background independence of general relativity arises as an emergent property is an open question. The answer to this question will determine whether or not gravity plays a "special role" in this underlying theory similar to its role in general relativity.

Gravitomagnetism

Sometimes called Gravitoelectromagnetism, (abbreviated GEM), refers to a set of formal analogies between Maxwell's field equations and an approximation to the Einstein field equations for general relativity, valid under certain conditions. For instance, the most common version of GEM is valid only far from isolated sources, and for slowly moving test particles.

This approximate reformulation of gravitation as described by general relativity makes a "fictitious force" appear in a frame of reference different from a moving, gravitating body. By analogy with electromagnetism, this fictitious force is called the gravetomagnetic force, since it arises in the same way that a moving electric charge creates a magnetic field, the analogous "fictitious force" in special relativity.

The main consequence of the gravetomagnetic force, or acceleration, is that a free-falling object near a massive rotating object will itself rotate.

This prediction, often loosely referred to as a gravitomagnetic effect, is among the last basic predictions of general relativity yet to be directly tested. A group at Stanford University is currently analyzing data from the first direct test of GEM, the Gravity B satellite experiment. Frame-dragging is often mentioned as a gravitomagnetic effect, but the Lense-Thirring effect (precession) may be a more appropriate example.
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Plato: Gravitational Wave Detectors are Best
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Monday, August 21, 2006

Gravitational Waves


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Gravitational waves click here for Wavy.gif

With space and time not as rigid background structures, but as dynamical objects (changing as the world changes in and around them), general relativity predicts fundamentally new phenomena. One of the most fascinating is the existence of gravitational waves: small distortions of space-time geometry which propagate through space as waves!

Most readers will have encountered several wave phenomena in everyday life. Sound waves, for instance: a small region of air is compressed, and the fact that its inner pressure is a bit higher than that of neighbouring regions leads to its expansion.

This expansion leads to compression nearby, and in this way, the slight surplus in pressure propagates further and further. Such pressure waves are produced when we talk: our vocal cords compress the air around them, sound travels as waves, and these waves are absorbed by our ears when we hear them.

In Einstein's case, the situation is somewhat different, but the basic principle is the same: a slight distortion in one region of space distorts nearby regions, and in the end, there is a moving distortion which speeds along at the highest possible speed (the speed of light). Such travelling distortions of space geometry are called gravitational waves.

Einstein Online: Elementary Quantum Loops
Plato: Gravitational Wave Detectors are Best
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Youth is the gift of nature, but age is a work of art.
Stanislaw Lec more Famous Quotes
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Saturday, August 19, 2006

Symmetry in Supergravity


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Double Pupil by flickr photos: cyberchaos

An attempt of a Unified Field Theory using acceleration in place of gravitation. Let us now explain that fermions have mass, weight and charge. Let us also explain that bosons have no mass, weight and charge. Now back to the subject at hand, mass in a gravitational field is directly related to the effects of that gravitational field. Mass in an acceleration field is directly related to the effects of that acceleration field. In other words mass has a symmetrical relationship with acceleration and gravitational fields. The mass itself does not know the difference and therefore the effects upon the mass are the same. An acceleration or a gravitational field can vary depending upon the origin.

Gravity
Gravity is due to a change in the curvature of space-time produced by the presence of matter. Matter accelerating creates 'pseudo gravity' or a change in the curvature of space-time. In the vacuum of space, if the means of mass acceleration stops the mass will then be riding on a soliton wave of gravitons and will maintain a constant velocity unless disturbed by a gravitational field.

The patent could possibly be a macroscopic conjecture of supergravity. If operating in a 'super-conducting' environment, the four armatures can be four new generators that "behave" as spinors and vary as a function of the propagation translation. The concept of an electric motor to generate translational force provides us with the means to propagate systems over vast distances in space. Electric power can be generated with no need to refuel rocket systems; explaining the benefits of "Supergravity a Supersymmetry."

An good example of systems moving in zero gravity of space would be the orbits of two planets around Barnard's star. They cause the wobble of the Star's observed motion. This system makes Barnard's star travels in a erratic wave fashion that was first discovered by Barnard.
The force between the Earth and it's moon is generated by a flood of virtual gravitons being exchanged between the two bodies. This force is completely dynamic in nature just as the Universe is dynamic and not static.

The development of a theory of gravitation based on the exchange of gravitons and the unification of this theory with the GUT (Grand Unified field Theory) is the task that this generation of inventors like Mr. Navarro have undertaken.

Energy in the vacuum of space is abundant and available. According to modern physics, a vacuum isn't a pocket of nothingness. It churns with unseen activity. Bosons are continually flowing and communicating with masses over vast distances in space. Gravitons spend most of their time patiently waiting for masses to accelerate with, however they are never fully at rest.
Gravitons and Bosons are the "Missing Dark Matter" in our universe.
Gravity can be created by acceleration, either rotational or linear. We shall call this gravity created from acceleration pseudo gravity. Stop the acceleration and the pseudo gravitational field is gone.

Power can be turned on to an electromagnet creating a flow of photons that generate the magnetic field. Shut the power off and the magnetic force field dissipates. The bosons are already present to the vacuum of space or any gravitational field.
These scalar fields occupy all space and do not contradict the established laws of physics. Space and Time is the same everywhere. Einstein devoted the last 30 years of his life in search for a "unified field theory," which would unite space-time and gravitation with Maxwell's theory of electromagnetism.

Unified field theory [Thomas L. Navarro]
A theory which attempts to express asymmetrical binary system/systems acceleration about a axis of rotation and electromagnetism within a single unified framework. This attempt is to validate Einstein's general theory of relativity with a theory of acceleration in place of gravitation. These new theories from F=MA Inc. implements the acceleration field from asymmetric binary systems rotating about a center axis unified with new technologies in electromagnetism.

Like other physical symmetries, extended supergravity can also be viewed in terms of a "superparticle" with an arrow in an auxiliary space of many dimensions. As the arrow rotates, the particle becomes in turn a graviton, a gravitino, a photon, a quark and so on. The quanta of all the forces are present in the universe, and they are unified, or derived from a common source, the virtual cosmos of bosons that is occupied with billions of galaxies of fermions.

The four forces of nature are the following:
(1) Strong force with a strength of one, a short range, acts on particles called quarks, and the virtual particle exchanges are gluons, and the nature of force between identical particles is repulsive.
(2) Electromagnetic force with a strength of ten to the negative squared, a long range, acts on particles electrically charged, and the virtual particle exchange are photons, and the nature of force between identical particles is repulsive.
(3) Weak force with a strength of ten to the negative fifth, a short range, acts on particles of electrons, neutrinos and quarks, and the virtual particle exchange are intermediate vector bosons, and the nature of force between identical particles is repulsive.
(4) Gravitational force with a strength of ten to the negative thirty-ninth, a long range force, acts on all particles, and the virtual particle exchange are gravitons, and the nature of force between identical particles is attractive.

Particles with half-integer spin (such as 1/2, 3/2, 5/2) are fermions, and they obey the exclusion principle formulated by Pauli, which states that no two identical fermions can occupy the same point in space or more generally, the same quantum state. This force explains the stability of white-dwarf stars and neutron stars, which without it would collapse into black holes under the attractive gravitational force.

Particles with integer spin, such as bosons have statistics are entirely different. The fact that two or more bosons occupy the same point in space or the same quantum state. Such superpositions of many identical bosons can lead to macrospic observable effects. For example, laser light is superposition of many photons with the same energy and direction. Let us look at a small amount of mass at rest; now let's accelerate this mass; it becomes more massive or gains kinetic energy from acceleration, and a simple explanation of this event is the gravitons have accumulated on the mass as the mass accelerates giving the mass the kinetic energy equals one half the mass times the velocity squared. If a small amount of mass is tossed at you from my hand, it has minimum amount of kinetic energy, however if it is accelerated somehow to a higher velocity towards you, the small amount of mass can suddenly become destructive, because it has gained kinetic energy, or quite simply accumulated gravitons, and it is wise to avoid the impact of this small amount of mass. The gravitons (bosons) have through their attractive nature joined the mass (fermions) as it accelerates, in the gravitational fields of earth, (or out in deep space far removed from any gravitational field).

Bosons tend to be associated with force. Two or more bosons can occupy the same space, whereas fermions are associated with matter. Gravitons are bosons and positively gather together. There is no objection to any number of them sharing the same space. The gain of mass as a fermions is the gravitons joining the fermions as it accelerates, the faster the fermions accelerates the more gravitons jump on to join the fermions.


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The world's most powerful accelerator of electrons is at Stanford in California. This great electric gun two miles long; the electrons emerge from the 'muzzle' about 40,000 times heavier than when they started. All of that extra mass is energy of motion. The electrons (fermions) have accumulated gravitons (bosons). Gravitons are attracted to mass under acceleration and make the electron emerge 40,000 times heavier.

Now you see how simple it is. It has always been in plain view, as a car has more mass when in motion than when at rest.

Supersymmetry unites bosons and fermions into a single theory.
Gravitons cannot be seen; they are responsible for kinetic energy being equal to 1/2 the mass times the velocity squared.

Original Text from Supersymmetry dot com
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Every noble work is at first impossible. Thomas Carlyle
Knowledge is the eye of desire and can become the pilot of the soul.
Will Durant more Famous Quotes

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Friday, August 18, 2006

The Treasure Within


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The Treasure Within by dailyville
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Science Friday with: Lee Smolin and Brian Greene
Thanks for link to Lubos Motl @ The Reference Frame
More Science from Sabine Hossenfelder @ Backreaction

And special for JoAnne Hewett @ cosmicvariance
Symmetry Graphic double pupil by cyberchaos
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The more you can dream, the more you can do.
Michael Korda more Famous Quotes
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Thursday, August 17, 2006

Dimensions in Light


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Isaac Newton
From 1670 to 1672 lectured on optics.

During this period he investigated the refraction of light, demonstrating that a prism could decompose white light into a spectrum of colours, and that a lens and a second prism could recompose the multicoloured spectrum into white light. He also showed that the coloured light does not change its properties, by separating out a coloured beam and shining it on various objects. Newton noted that regardless of whether it was reflected or scattered or transmitted, it stayed the same colour.

Thus the colours we observe are the result of how objects interact with the incident already-coloured light, not the result of objects generating the colour. For more details, see Newton's theory of colour. Many of his findings in this field were criticized by later theorists, the most well-known being Johann Wolfgang von Goethe, who postulated his own colour theories.

A replica of Newton's 6-inch reflecting telescope of 1672 for the Royal Society.
From this work he concluded that any refracting telescope would suffer from the dispersion of light into colours, and invented a reflecting telescope (today known as a Newtonian telescope) to bypass that problem. By grinding his own mirrors, using Newton's rings to judge the quality of the optics for his telescopes, he was able to produce a superior instrument to the refracting telescope, due primarily to the wider diameter of the mirror. (Only later, as glasses with a variety of refractive properties became available, did achromatic lenses for refractors become feasible.) In 1671 the Royal Society asked for a demonstration of his reflecting telescope. Their interest encouraged him to publish his notes On Colour, which he later expanded into his Opticks. When Robert Hooke criticised some of Newton's ideas, Newton was so offended that he withdrew from public debate. The two men remained enemies until Hooke's death.

In one experiment, to prove that colour perception is caused by pressure on the eye, Newton slid a darning needle around the side of his eye until he could poke at its rear side, dispassionately noting "white, darke & coloured circles" so long as he kept stirring with "ye bodkin."

Newton argued that light is composed of particles, but he had to associate them with waves to explain the diffraction of light. Later physicists instead favoured a purely wavelike explanation of light to account for diffraction.

Today's quantum mechanics restores the idea of "wave-particle duality", although photons bear very little resemblance to Newton's corpuscles (e.g., corpuscles refracted by accelerating toward the denser medium).


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(dubious assertion—see talk page)
Newton is believed to have been the first to explain precisely the formation of the rainbow from water droplets dispersed in the atmosphere in a rain shower. Figure 15 of Part II of Book One of the Opticks shows a perfect illustration of how this occurs.


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Before Max Planck suggested that light is quantized, optics consisted mainly of the application of electromagnetism and its high frequency approximations to light.

Classical optics divides into two main branches:
geometric optics and physical optics.

Geometric optics, or ray optics, describes light propagation in terms of "rays". Rays are bent at the interface between two dissimilar media, and may be curved in a medium in which the refractive index is a function of position. The "ray" in geometric optics is an abstract object which is perpendicular to the wavefronts of the actual optical waves. Geometric optics provides rules for propagating these rays through an optical system, which indicates how the actual wavefront will propagate. Note that this is a significant simplification of optics, and fails to account for many important optical effects such as diffraction and polarization.

Geometric optics is often simplified even further by making the paraxial approximation, or "small angle approximation." The mathematical behavior then becomes linear, allowing optical components and systems to be described by simple matrices. This leads to the techniques of Gaussian optics and paraxial raytracing, which are used to find first-order properties of optical systems, such as approximate image and object positions and magnifications.

Gaussian beam propagation is an expansion of paraxial optics that provides a more accurate model of coherent radiation like laser beams. While still using the paraxial approximation, this technique partially accounts for diffraction, allowing accurate calculations of the rate at which a laser beam expands with distance, and the minimum size to which the beam can be focused.

Gaussian beam propagation thus bridges the gap between geometric and physical optics.

Physical optics models the propagation of complex wavefronts through optical systems, including both the amplitude and the phase of the wave. This technique, which is usually applied numerically on a computer, can account for diffraction, interference, and polarization effects, as well as aberrations and other complex effects. Approximations are still generally used, however, so this is not a full electromagnetic wave theory model of the propagation of light. Such a full model would (at present) be too computationally demanding to be useful for most problems, although some small-scale problems can be analyzed using complete wave models.
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Newton the Alchemist by Plato
The Chemistry of Isaac Newton Symbols Guide @ Indiana edu
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Wednesday, August 16, 2006

Antimatter factory

The Antimatter Factory (by Django Manglunki)
Over the past 20 years scientists at CERN have been using antiparticles in many different ways for their daily work. Antiparticles can be generated by colliding subatomic particles. Before being delivered to the various physics experiments, they must be isolated, collected and stored in order to tune their energy to the appropriate level.
Until now, each of these steps has been carried out by a dedicated machine with the main purpose of providing high energy antiparticles.
But now the first "self-contained antiproton factory", the Antiproton Decelerator (or AD), is operational at CERN . It will produce the low energy antiprotons needed for a range of studies, including the synthesis of antihydrogen atoms - the creation of antimatter.

Live from CERN: antimatter


In 1997 Scientists found evidence of two large clouds of antimatter located in the Milky Way Galaxy which may be linked to a large black hole in the center of our galaxy or supernova explosions of massive stars. Scientists from Northwestern University, the Naval Research Laboratory (NRL), and other institutions used an instrument on the Compton Gamma Ray Observatory to find two clouds of antimatter. One large cloud was found in a region surrounding the center of the galaxy, while a second plume of antimatter extended up to 3,000 light-years above the Milky Way's core. The second plume of antimatter was unexpected and has yet to be explained. "The origin of this new and unexpected source of antimatter is a mystery," said Northwestern University physics professor William Purcell. James R. Kurfess of NRL outlines three possible sources for the antimatter plume. "The antimatter cloud could have been formed by multiple star bursts occurring in the central region of the galaxy, jets of material from a black hole near the galactic center, the merger of two neutron stars, or it could have been produced by an entirely different source," he said. The astronomers used the Oriented Scintillation Spectrometer Experiment (OSSE), one of the instruments on the orbiting gamma-ray observatory. The instrument detects gamma rays produced when positrons, the antimatter version of electrons, come into contact with regular matter and annihilate. "It's possible that this mapping effort could turn up evidence for other unexpected clouds of positrons," Kurfess said. "We will keep monitoring the center of the Galaxy in the hope of seeing evidence for a black hole 'turning on' and producing positrons," he added.

Spaceviews: NASA Press release May 1997
blackhole production and sonluminence by Plato
antimatter: mirror of the universe from CERN
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Quote of the Day:
Action and reaction, ebb and flow, trial and error, change -
this is the rhythm of living. Out of our over-confidence, fear;
out of our fear, clearer vision, fresh hope. And out of hope, progress.
Bruce Barton
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Dark Matter


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Pentagon Strike

Did the US Administration stage the 9/11 strike on the Pentagon
to get public support for a pre-planned US military invasion of Iraq
to elect an interim government which favours trade with the US
and thus secure free flowing supplies of Iraqi Oil.

The truth is stranger than fiction. - Wolves in sheep's clothing
Click on pentagonstrike Preloader to see the real video evidence.

"That very first day, on September 12, one day after September 11... the meeting that was held in the White House, in the situation room... led to Rumsfeld asking the question, “Shouldn’t we use this as an opportunity to do something about Iraq as well?”" - Bill Christison.

Was PM Tony Blair aware of these facts or simply led by the nose
Do the American people condone this type of freedom & democracy

Is it time to exile Dick Cheney, Donald Rumsfeld
Son of Bush & Tony Blair to St Helena.

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All The World is a Stage - William Shakespeare
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Tuesday, August 15, 2006

Geometry & Soap Bubbles


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Picture from www o exo o net thanks to Bee @ Backreaction blogspot

Everyone knows that human societies organize themselves.
But it is also true that nature organizes itself, and that the principles by which it does this is what modern science, and especially modern physics, is all about.

from self organization of matter by Plato
more from fortunecity - what lies beneath


Harmonic Oscillations
Can harmonic oscillators serve as a bridge between quantum mechanics and special relativity.

The quantum harmonic oscillator has implications far beyond the simple diatomic molecule. It is the foundation for the understanding of complex modes of vibration in larger molecules, the motion of atoms in a solid lattice, the theory of heat capacity, etc. In real systems, energy spacings are equal only for the lowest levels where the potential is a good approximation of the "mass on a spring" type harmonic potential. The un-harmonic terms which appear in the potential for a diatomic molecule are useful for mapping the detailed potential of such systems.

further reading: harmonic oscillation by Plato
original text from hyperphysics from gsu edu


Wavelengths of elecromagnetic radiation
According to the basic laws of physics, every wavelength of electromagnetic radiation corresponds to a specific amount of energy.
The NIST/ILL team determined the value for energy in the Einstein equation, E = mc2, by carefully measuring the wavelength of gamma rays emitted by silicon and sulfur atoms.

At what point does the universe make itself known by Plato
NIST National Institute of Science & Technology Public Affairs
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The Standard Model of Fundamental Particles and Interactions Chart
From stillness born by Plato
Image: Cosmologicalcomposition
wikipedia: Dark Matter
wikipedia: Bullet Cluster
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Quote of the Day. Formula for success:
Rise early, work hard, strike oil. J. Paul Getty
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Monday, August 14, 2006

Bubbles on My Mind


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Rain courtesy of Anup Kumar Jana @ xtremecolors

I'm going somewhere with this one,
I just haven't figured where yet.

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Quote of the Day:
It is well that war is so terrible. We should grow too fond of it.
Robert E. Lee more Famous Quotes
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Sunday, August 13, 2006

Nectar of the gods


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Just Because
hummingbird picture from Diana @ minemymind
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Quote of the Day:
Really great people are, above everything else,
courteous, considerate and generous -
not just to some people in some circumstances -
but to everyone all the time. Thomas J. Watson
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Saturday, August 12, 2006

Out on a Ledge


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To Jump or Not To Jump - That is the Question
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Don't gain the world and lose your soul,
wisdom is better than silver or gold.
Bob Marley more Famous Quotes
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Friday, August 11, 2006

Relative Reality


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Here's wishing
all you Peace loving people a great weekend,
as for the rest like Red said to Scarlett O'Hara:
"frankly my dear, I couldn't give a dam"

This weekend Tv off - I have no wish to hear the name of
that God forsaken land or the false inheritors who claim it.
If the earth were to open up and swallow them up whole
it would be a good day I would lose no sleep or shed a tear
both sides are long long past my sympathy or contempt. -

I'll be giving Blair & the UN a piece of my mind next week- Q
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Graphs & wisdom courtesy of Peter @ Alaqa! blogspot
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Quote of the Day: All I need to make a comedy
is a park, a policeman and a pretty girl.
Charlie Chaplin more Famous Quotes
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