Lei feng's network; the author of der Spiegel, Max Planck Institute for gravitational physics PhD, members of the LIGO scientific collaboration organizations. Article first, public intellectuals.
"In addition to using gravitational waves of stellar evolution, black holes and beyond general relativity research previously impossible, once detected gravitational waves corresponding to incident electromagnetic wave, is able to determine the events of Galaxy. If not detected gravitational waves corresponding to incident electromagnetic wave, if gravitational waves in the future measurement of accuracy or gravity waves observed nearer the event, gravitational waves can be measured in the direction of higher precision, combined with gravitational wave distance measurement itself can determine the gravitational waves, is likely to permit to identify the events of Galaxy. The redshift of galaxies are relatively easy to measure, so can new gravitational waves as "standard candles" study on the expansion of the universe. Compare Supernova standard candles, gravitational wave standard candle clean and accurate, and is not dependent on the cosmic distance ' ladder '. Therefore, not only the era of gravitational wave astronomy is inexorably coming, cosmology gravitational waves will also become a new area of research, stellar evolution, black holes, formation and evolution of the universe is of epoch-making significance of the study. "
--The intellectuals invited researcher at the Chinese Academy of Sciences, Institute of high energy physics commented Zhang shuangnan
► LSC spokesman, Professor of physics and astronomy at the University of Louisiana announced Gabriela González, LIGO again found black holes and gravitational waves!
| "From Einstein's Christmas gift"
Was first detected in humans twin black holes and gravitational waves produced by GW1509143 months later, the LIGO again observed a pair of black holes and gravitational wave signals produced were: GW151226. In the LSC (LIGO scientific collaboration), when most scientists immersed in the Christmas holiday, the "space-time ripples" as a Christmas gift, on December 26, 2015 UTC (coordinated universal time) arrived at 03:38:53.
And GW150914 is similar to GW151226 also came from two black holes merging. This incident occurred in depths about 1.4 billion light-years away, two were 14.2 and 7.5 times solar-mass black holes, due to gravitational radiation during each other slowly, in the final seconds, they happened and generated 20.8 times solar-mass black holes. In the process, about one solar mass of radiation in the form of gravitational waves in the universe, peak strength of gravitational wave brighter than the whole universe more than 10 times.
► In the United States the LIGO Hanford (H1, left) and Livingston (L1, right) GW151226 gravitational wave detectors observed events. Marcelo Burlon iPhone 5 Case
Diagram shows the two LIGO detectors have observed gravitational waves generated by the event intensity over time and frequency changes. Two graphs show the GW151226 signal in the time of 1 second "sweep" from 30Hz to 800Hz. And GW150914, because of the quality of the two black holes smaller, so before the signals on the graph is not so obvious. (This image copyrighted by LSC/Virgo all Collaboration)
► Significant analysis of the GW151226 event. You can see the significance of this event is greater than 5 times the standard deviation, so this is a clearly defined scientific discoveries. (This diagram LSC/Virgo Collaboration all rights reserved)
| Hard twice, once a suspected gravitational wave event
In addition to the above two gravitational wave events, on October 12 last year, LSC scientists also found a suspected gravitational wave event: LVT151012. Why say it is suspected, because this event is far away (about 3 billion light-years away), signal to noise ratio is relatively weak, obviously only 1.7 times the standard deviation, therefore cannot be determined as scientific discoveries. But many within the LSC scientists tend to believe that this is a black hole and close the event.
Prior to the GW151226 and GW150914, and LVT151012, what similarities and differences are there?
► Twice found LIGO gravitational wave events and comparing a suspect event.
First, please note events of signal to noise ratio also has a pair of black hole's mass, luminosity distance. Marcelo Burlon iPhone 5 Cases
A little a little GW151226 than GW150914 (1.4 billion light years, respectively, and 1.3 billion light years), and the mass of the black hole in the system is smaller than GW150914, so GW151226 the signal to noise ratio is 13 (less than GW150914 23.7). However, GW151226 also significantly greater than 5 times the standard deviation can be considered a new gravitational-wave detection. LVT151012 because of the far distance, signal to noise ratio and significantly low, as only a suspected gravitational wave event.
Second, GW151226 two of the mass of the black hole is minimal, so it does take a long time, the detection range of the detector within the duration of the signal is about 1 second, and GW150914 only 0.2 seconds.
Third, after three events are displayed and a new spin of the black hole has a large value (0.7 per cent).
Finally, in the sky on the positioning accuracy, LIGO GW150914 most accurate, within the range of 230 square (square of the point, similar to the difference in square meters and meters).
For the weak LVT151012, location does not scope 1600 square degrees. For gravitational wave event square degrees of determination and the associated signal strength. The stronger the signal, the more precise determination of location. Of course, the new VIRGO detectors such as line (the end of this year), then we will have three gravity wave detectors, one more "ears", the area of the future gravitational wave event location accuracy will be greatly enhanced.
► GW150914 and GW151226 area, after VIRGO can be seen on the line, area location determination accuracy will be greatly improved. (This diagram LSC/Virgo Collaboration all rights reserved)
Finally, the observation time, these three events are found in high-tech running LIGO O1 phase (GW150914 was found in O1 is run before the trial operation stage), in just three months time, we discovered three gravitational wave event. O2 sensitivity is about to run higher, observing events for longer, you can imagine that after one year in this form would be much longer!
| Impact on Astrophysics
After the first GW150914, many astrophysicists with so much quality in the universe-black hole system is amazing. X-ray binary stars (X-ray binary) observations showed that there is no such a massive black hole system. In addition, some black hole theory (such as common packet layer theory) could explain how such a massive black hole system formed, but humanity's first gravitational wave events in such supermassive, strongly suggests that the existing larger-mass black hole for Astrophysics and collection rates are underestimated. This GW151226 double black hole x-ray binary star observations of black hole mass range, this means that the gravitational wave data for the first time can be compared with other means of observation data, this is of great significance for Astrophysics.
► Which x-ray black hole has been observed (orange) observed black holes and gravitational waves (blue and green) quality.
Found by gravitational waves of the mass of the black hole are quite large. Due to gravitational wave observation data, refresh the human perception of black hole mass distribution. (Image from gravity.Astro.cf.AC.UK)
GW151226 found the theory of black hole formation is also a very important indicator.
Now there are many theories of the formation of a black hole. Some theories believe that, after a pair of massive stars to produce a common evolution, culminating in the last phase of their life the dual black hole system. Also there are some theories that, in certain regions of the universe, stars gathered more closely, black hole systems may also be formed in the beginning of the two respective evolution of massive stars at each other after the final formation of the binary star system. GW151226 observation and the formation of the two theories are consistent with the data, so at this stage we are not able to decide which theory is more likely.
In addition, GW151226, GW150914, and LVT151012 shows that stellar-mass black hole in the universe more than we thought. These initial discoveries in our understanding of these two black holes is a very important first step, until we are totally ignorant about this information. First event may be called "discovery", the second incident can be said to be "statistics", but three times and things will be "distributed"! According to the observations of the three events, our black hole or not rate estimates of: 9-240 per cubic metre of Gpc within the space of a year and the black hole. Believe with the run of O2, O3, there will be an increasing number of gravitational wave event is to be found. Exciting gravitational wave astronomy, has been towards a golden age!
Lei Feng network Note: the authorized network of Lei Feng by the author in this paper (search for "Lei feng's network", public interest) released, please contact the authorized, and retain full information content must not be modified.
2838 votes
Smartisan T1
"Hammer the phone" is a hammer technologies (Beijing) limited design and development of a high-end Smartphone. Using Smartisan based on customized Android OS smartphone operating system.
View details of the voting >>
No comments:
Post a Comment