Einstein At Least 99.95 Percent Right

[abrar]

Peace and greetings,

I previously posted wormholes mentioned in Quran and there was even a debate about Quantum mechanics versus Einstien's Relativity in the post criticism of mecca and kaaba about an argument on space and time. Some people accused me of unreliable information simply because i gave some of the references from wikipedia. Now I am giving referenes from the Official NASA website and mainstream reliable scientific sources for latest developments in the theory of relatvity.

General Relativity Survives Gruelling Pulsar Test Einstein At Least 99.95 Percent Right.

Science Daily ? An international research team led by Prof. Michael Kramer of the University of Manchester's Jodrell Bank Observatory, UK, has used three years of observations of the "double pulsar", a unique pair of natural stellar clocks which they discovered in 2003, to prove that Einstein's theory of general relativity - the theory of gravity that displaced Newton's - is correct to within a staggering 0.05%. Their results are published on the14th September in the journal Science and are based on measurements of an effect called the Shapiro Delay.

http//www.sciencedaily.com/images/2006/09/060914094623.jpg Here's a depiction of the double pulsar system currently being tracked by the international team of radio astronomers who discovered it, including Dr. Duncan Lorimer and Dr. Maura McLaughlin of West Virginia University. The pulsars are the remnants of two massive stars that burned out by way of supernova explosions. They measure just 12 miles across, but each weighs more than our own Sun. Note the "bend" in the space-time fabric from the sheer mass of the two bodies. (Image courtesy of West Virginia University)

The double pulsar system, PSR J0737-3039A and B, is 2000 light-years away in the direction of the constellation Puppis. It consists of two massive, highly compact neutron stars, each weighing more than our own Sun but only about 20 km across, orbiting each other every 2.4 hours at speeds of a million kilometres per hour. Separated by a distance of just a million kilometres, both neutron stars emit lighthouse-like beams of radio waves that are seen as radio "pulses" every time the beams sweep past the Earth. It is the only known system of two detectable radio pulsars orbiting each other. Due to the large masses of the system, they provide an ideal opportunity to test aspects of General Relativity

Gravitational redshift the time dilation causes the pulse rate from one pulsar to slow when near to the other, and vice versa.
Shapiro delay The pulses from one pulsar when passing close to the other are delayed by the curvature of space-time. Observations provide two tests of General Relativity using different parameters.
Gravitational radiation and orbital decay The two co-rotating neutron stars lose energy due to the radiation of gravitational waves. This results in a gradual spiralling in of the two stars towards each other until they will eventually coalesce into one body.
By precisely measuring the variations in pulse arrival times using three of the world's largest radio telescopes, the Lovell Telescope at Jodrell Bank, the Parkes radio-telescope in Australia, and the Robert C. Byrd Green Bank Telescope in West Virginia, USA, the researchers found the movement of the stars to exactly follow Einstein's predictions. "This is the most stringent test ever made of General Relativity in the presence of very strong gravitational fields -- only black holes show stronger gravitational effects, but they are obviously much more difficult to observe", says Kramer.

Since both pulsars are visible as radio emitting clocks of exceptional accuracy, it is possible to measure their distances from their common centre of gravity. "As in a balanced see-saw, the heavier pulsar is closer to the centre of mass, or pivot point, than the lighter one and so allows us to calculate the ratio of the two masses", explains co-author Ingrid Stairs, an assistant professor at the University of British Columbia in Vancouver, Canada. "What's important is that this mass ratio is independent of the theory of gravity, and so tightens the constraints on General Relativity and any alternative gravitational theories." adds Maura McLaughlin, an assistant professor at West Virginia University in Morgantown, WV, USA.

Though all the independent tests available in the double pulsar system agree with Einstein's theory, the one that gives the most precise result is the time delay, known as the Shapiro Delay, which the signals suffer as they pass through the curved space-time surrounding the two neutron stars. It is close to 90 millionths of a second and the ratio of the observed and predicted values is 1.0001 +/- 0.0005 - a precision of 0.05%.

A number of other relativistic effects predicted by Einstein can also be observed. "We see that, due to its mass, the fabric of space-time around a pulsar is curved. We also see that the pulsar clock runs slower when it is deeper in the gravitational field of its massive companion, an effect known as "time dilation".

A key result of the observations is that the pulsar's separation is seen to be shrinking by 7mm/day. Einstein's theory predicts that the double pulsar system should be emitting gravitational waves - ripples in space-time that spread out across the Universe at the speed of light. "These waves have yet to be directly detected ", points out team member Prof. Dick Manchester from the Australia Telescope National Facility, "but, as a result, the double pulsar system should lose energy causing the two neutron stars to spiral in towards each other by precisely the amount that we have observed - thus our observations give an indirect proof of the existence of gravitational waves."

Michael Kramer concludes; "The double pulsar is really quite an amazing system. It not only tells us a lot about general relativity, but it is a superb probe of the extreme physics of super-dense matter and strong magnetic fields but is also helping us to understand the complex mechanisms that generate the pulsar's radio beacons." He concludes; "We have only just begun to exploit its potential!"

Note This story has been adapted from a news release issued by Particle Physics & Astronomy Research Council.

The following is information from NASA's official website .

http//www.nasa.gov/missions/science/gpb_tests.html

NASA Puts Einstein to the Test 10.26.04

Was Einstein right? NASA is gathering proof 88 years later.

To test this claim in a way never done before, NASA launched the Gravity Probe B (GP-B) mission in April 2004. If all goes well with this satellite experiment, we should know by mid-2006 whether Einstein's theory of curved spacetime is a true description of our universe.

Einstein's theory, more formally known as the Theory of General Relativity, states that any mass, such as the Earth, warps space and time around it. And any object traveling near the Earth must follow this curve or warp in spacetime. The result is that the object falls toward the Earth. Newton claimed the force of gravity caused this effect; Einstein claimed it was the warp of spacetime around the Earth.

http//www.nasa.gov/images/content/67634main_GPB4_330x248.jpgImage right Artist concept of Gravity Probe B spacecraft in orbit around the Earth (NASA/MSFC)

A second, and even more remarkable, Einstein prediction is that the spinning Earth should twist spacetime around with it -- an effect called "frame-dragging." Any object in space near the Earth should respond to that twist of spacetime by turning with it.

This is the principle behind the Gravity Probe B mission -- watching an object in space to see if it responds to "frame-dragging" caused by the Earth's rotation.

Inside this 21-foot-tall satellite, now orbiting 400 miles above the Earth, are four spinning spheres, called gyroscopes. At the beginning of the experiment, a telescope on-board the satellite and the spin axes of the four gyroscopes were all pointed directly at a distant "guide" star, named IM Pegasi. Throughout the experiment, the spacecraft's telescope remains pointed at IM Pegasi, providing a constant reference line for measuring any turn in the pointing direction of the gyroscopes' spin axes. If Einstein's prediction is correct, the twisting spacetime near the Earth should cause the gyroscopes' spin axes to turn away from this reference line by the very tiny angle of 1/100,000th of a degree over the course of a year.

To measure this miniscule turn, Gravity Probe B created four near-perfect spheres. Each gyroscope is less than three 10-millionths-of-an-inch from perfect roundness. They are so close to perfect, in fact, that they are listed in the 2005 edition of the Guinness Book of World Records as roundest objects ever made in the world. The spheres spin in near-isolation in a near-vacuum, near absolute zero, suspended inside a housing, protected from any magnetic, electric or solar forces.

In fact, most of this experiment uses one-of-a-kind record-setting equipment. Gravity Probe B will be the longest space mission kept near absolute zero -- 450?F below zero for 12 months. It can sense any change in the gyroscopes' position to within one 10-millionth of a degree. It controls the motion of the satellite with thrusters that produce forces softer than a human breath.

"It's been a long, amazing road to get to this point," said Rex Geveden, deputy director of NASA's Marshall Space Flight Center in Huntsville, Ala., which manages the Gravity Probe B program for NASA. "When Gravity Probe B was first proposed more than 40 years ago, the technology required for this experiment did not yet exist. At least nine new technologies had to be invented and perfected."

If Gravity Probe B's results are consistent with Einstein's theory, it will help solidify our understanding of phenomena like black holes and quasar jets. If, however, its results are not consistent with the predictions of General Relativity, it will require a significant revision of our theory of the fundamental structure of the universe.

Was Einstein right? After two billion spins of the gyroscopes and 7,000 orbits of the Earth, Gravity Probe B should know the answer.

For more information about Gravity Probe B, visit http//www.gravityprobeb.com/

Following is the latest update on gravity probe B mission of NASA

http//einstein.stanford.edu/

STATUS UPDATE AS OF 22 DECEMBER 2006

GP-B DATA ANALYSIS & RESULTS ANNOUNCEMENT STATUS

Note We've received several inquiries about a news story on GP-B in the current issue of Nature (Vol. 444, 21-28 December 2006, pp. 978-979). You'll find our response in this month's GP-B Mission News below.

During the 50-week science phase of the GP-B mission and the 7-week instrument calibration phase, which lasted from August 2004-September 2005, we collected over a terabyte of experimental data. Analysis of this data has been steadily progressing through a 3-phase plan, each subsequent phase building on those preceding it.

In Phase I, which lasted from the end of September 2005 through February 2006, the analysis focused on a short-term, day-by-day or even orbit-by-orbit, examination of the data. The overall goals of this phase were to optimize the data analysis routines, calibrate out instrumentation effects, and produce initial "gyro spin axis orientation of the day" estimates for each gyro individually. At this stage, the focus was on individual gyro performance; there was no attempt to combine or compare the results of all four gyros, nor was there even an attempt to estimate the gyro drift rates.

Phase II, which lasted from March-August, 2006, focused on understanding and compensating for certain long-term systematic effects in the data that spanned weeks or months. During this phase, the team was accurately able to model the time-varying polhode paths of the four gyros, as reported in last month's GP-B Mission News story, yielding increased precision for gyro precession rates over short intervals. This modeling of the gyro polhode behavior plus the development of a geometric interpretation of the data has enabled the team to make significant improvements in the precision of the analysis. Phase II concluded with the 15th meeting of our GP-B Science Advisory Committee (SAC) here at Stanford on 8-9 September 2006. During this important meeting, our data analysis team presented a complete progress report to the SAC.

As we come to the end of 2006, we are well into Phase III, in which the data from all four gyros is being integrated over the entire experiment. Now that the gyro polhode behavior is well understood, we are able to focus on identifying and addressing some subtle sources of noise and interference that are buried in the data, along with the relativity signals. During this final analysis phase, we are continuing to pursue both geometric and algebraic interpretations of the data, which is enabling us to make further improvements in the accuracy of the results.

The Phase III results will be relative to the position of our guide star, IM Pegasi, which changed continually throughout the experiment. This has been measured on our behalf by the Harvard-Smithsonian Center for Astrophysics (CfA). Thus, the final step in the analysis will be to combine our gyro spin axis orientation results with data mapping the proper motion of IM Pegasi relative to the unchanging position of a distant quasar.

At the conclusion of phase III, playing the role of our own harshest critic, our science team will perform a careful and thorough final review of the analysis and results, checking and cross-checking each aspect to ensure the soundness of our procedures and the validity of our outcomes. We will then turn the analysis and results over to the SAC, which has been closely monitoring our experimental methods, data analysis procedures, and progress for the past eight years, to obtain its independent review. Moreover, we will seek independent reviews from a number of international experts.

In addition to analyzing the data, members of our team are now in the process of preparing scientific and engineering papers for publication in 2007, including the reporting of the first results of this historic experiment at the American Physical Society (APS) Meeting in Jacksonville, FL on 14-17 April 2007. We have also begun discussions with NASA to plan a formal public announcement just prior to the APS meeting.

GP-B SPACECRAFT & MISSION STATUS
The GP-B space vehicle and payload continue to remain in good health. All active subsystems, including solar arrays/electrical power, Experiment Control Unit (ECU), flight computer, star trackers, magnetic sensing system (MSS) and magnetic torque rods, gyro suspension system (GSS), and telescope detectors, are performing nominally.

During the past few weeks, we completed final testing of the hibernation configuration and we have now ?tucked in the spacecraft for a long winter's nap.? We are continuing to monitor the health status of the spacecraft on a weekly basis and archiving the status data, but we no longer performing any significant operations on the vehicle or its payload. Because it is now in hibernation, there is no reason to continue reporting detailed status information.

The United States Air Force Academy (USAFA) is planning to conduct training for staff and cadets on the operation of the spacecraft during the month of January. Members of our GP-B Mission Operations Team will continue to support the USAFA to help them get their Mission Operations Center up and running.

As we conclude a very active and productive 2006, all of us here at GP-B would like to express our sincere appreciation to everyone who has been following this program--both on our Web site and via our email status updates. We look forward to sharing our experimental results with you in 2007. Until then, we wish you a joyous holiday season and a very happy new year!