Is Albert Einstein's Theory of General Relativity Still Valid?

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Recent release, passed through Ned Wright's Cosmology site:
http://www.astro.ucla.edu/~wright/cosmolog.htm#04Dec03

"A Double Radio Pulsar.
9 Jan 2004 - Lyne et al. (2004, Science in press) gives the details about PSR J0737-3039 A&B, the double radio pulsar binary with a relativistic orbit, previously reported as a single pulsar in a binary system on 4 Dec 2003. The mass of the 23 millisecond pulsar (A) is 1.337+/-0.005 M(sun) while the mass of the 2.8 second pulsar (B) is 1.250+/-0.005 M(sun). There are now 6 measured constraints on (MA,MB) and the values given above are consistent with all 6 constraints, providing a stringent test of General Relativity which GR passes with flying colors
". And:

"An amazing binary pulsar.
4 Dec 03 - Nature today published a paper (Burgay et al. 2003, Nature, 426, 531-533) about a newly announced millisecond pulsar, PSR J0737-3039, in a relativistic binary system. Radio pulsars are neutron stars (NS) which have a mass of about 1.4 solar masses and a radius of 10 km, magnetic fields billions to trillions of times larger than the Earth's magnetic field, and spin periods from 1.6 milliseconds to several seconds. PSR J0737-3039 is orbiting another neutron star every 2.4 hours and the two stars will merge in 85 Myr due to gravitational radiation. Hence LIGO will have many more detectable NS+NS merger events based on the statistics of two objects instead of the previous estimate based solely on the one merging binary pulsar PSR B1913+16 known earlier.

There is currently a program on the GBT radiotelescope schedule entitled "RRS Observations of the Double Binary Pulsar PSR J0737-3039" indicating that this is more than just a pulsar in orbit around a neutron star. And there is a Director's Discretionary Time Chandra observing proposal that says that both neutron stars in this system are pulsars, the previously announced pulsar with 22 millisecond period and a 2.7 second period for the companion. The millisecond pulsar (A) is eclipsed for 22 seconds as it passes behind the slow pulsar (the B component). Since the relative motion of the two stars is 14,000 km in 22 seconds, this eclipse must be caused by a wind coming from the B component instead of the disk of the neutron star which is tiny
".
 
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great news Labguy, thanks for posting this!
 


The recent release about the double radio pulsar, PSR J0737-3039 A&B, is certainly an exciting discovery in the field of cosmology. The fact that this binary system is providing a stringent test of General Relativity and has passed with flying colors is a testament to the progress we have made in understanding the laws of the universe. It is also amazing to think that these two neutron stars will eventually merge due to gravitational radiation, which will provide even more data for future studies.

Furthermore, the discovery of this double binary pulsar has implications for future observations and research. The fact that the GBT radiotelescope and Chandra observing proposal are already focused on studying this system shows the potential for even more groundbreaking discoveries. The fact that the eclipsing of the millisecond pulsar is caused by a wind from the slow pulsar is also a fascinating detail that adds to our understanding of these objects.

Overall, Albert is definitely still looking good with this recent release, and I look forward to seeing what further insights and discoveries will come from studying this double binary pulsar.
 
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