81-590: The Laser Interferometer Gravitational-Wave Observatory ( LIGO ) is a large-scale physics experiment and observatory designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Two large observatories were built in the United States with the aim of detecting gravitational waves by laser interferometry . These observatories use mirrors spaced four kilometers apart to measure changes in length—over an effective span of 1120 km—of less than one ten-thousandth
162-541: A Woodrow Wilson Fellow , Danforth Fellow , Guggenheim Fellow , and Fulbright Fellow . He has also received the honorary degree of doctor of humane letters from Claremont Graduate University and an honorary doctorate from the Physics Department of the Aristotle University of Thessaloniki . In 2024 he was awarded an honorary doctorate from University of Cambridge . He was elected to hold
243-437: A signal-to-noise ratio around 20 can be achieved, or higher when combined with other gravitational wave detectors around the world. Based on current models of astronomical events, and the predictions of the general theory of relativity , gravitational waves that originate tens of millions of light years from Earth are expected to distort the 4-kilometre (2.5 mi) mirror spacing by about 10 m , less than one-thousandth
324-613: A LIGO project based on the MIT study and on experimental work at Caltech, MIT, Glasgow, and Garching . Drever, Thorne, and Weiss formed a LIGO steering committee, though they were turned down for funding in 1984 and 1985. By 1986, they were asked to disband the steering committee and a single director, Rochus E. Vogt (Caltech), was appointed. In 1988, a research and development proposal achieved funding. From 1989 through 1994, LIGO failed to progress technically and organizationally. Only political efforts continued to acquire funding. Ongoing funding
405-445: A beam with a power of 20 W that passes through a power recycling mirror. The mirror fully transmits light incident from the laser and reflects light from the other side increasing the power of the light field between the mirror and the subsequent beam splitter to 700 W. From the beam splitter the light travels along two orthogonal arms. By the use of partially reflecting mirrors, Fabry–Pérot cavities are created in both arms that increase
486-534: A black hole when the critical circumference of the designed hoop can be placed around it and set into rotation. That is, any object of mass M around which a hoop of circumference 4 π G M c 2 {\displaystyle {\begin{matrix}{\frac {4\pi GM}{c^{2}}}\end{matrix}}} can be spun must be a black hole. As a tool to be used in both enterprises — astrophysics and theoretical physics — Thorne and his students have developed an unusual approach, called
567-487: A budget exceeding the previous proposals by 40%. Barish proposed to the NSF and National Science Board to build LIGO as an evolutionary detector, where detection of gravitational waves with initial LIGO would be possible, and with advanced LIGO would be probable. This new proposal received NSF funding, Barish was appointed Principal Investigator , and the increase was approved. In 1994, with a budget of US$ 395 million, LIGO stood as
648-540: A direct detection of gravitational waves. After the completion of Science Run 5, initial LIGO was upgraded with certain technologies, planned for Advanced LIGO but available and able to be retrofitted to initial LIGO, which resulted in an improved-performance configuration dubbed Enhanced LIGO. Some of the improvements in Enhanced LIGO included: Science Run 6 (S6) began in July 2009 with the enhanced configurations on
729-512: A five-year US$ 200-million overhaul, bringing the total cost to $ 620 million. On 18 September 2015, Advanced LIGO began its first formal science observations at about four times the sensitivity of the initial LIGO interferometers. Its sensitivity was to be further enhanced until it was planned to reach design sensitivity around 2021. On 11 February 2016, the LIGO Scientific Collaboration and Virgo Collaboration published
810-556: A leading proponent – in 1984, he cofounded the LIGO Project (the largest project ever funded by the NSF ) to discern and measure any fluctuations between two or more 'static' points; such fluctuations would be evidence of gravitational waves, as calculations describe. A significant aspect of his research is developing the mathematics necessary to analyze these objects. Thorne also carries out engineering design analyses for features of
891-624: A notable example of which was for the Christopher Nolan film Interstellar . Thorne was born on June 1, 1940, in Logan, Utah . His father, D. Wynne Thorne (1908–1979), was a professor of soil chemistry at Utah State University , and his mother, Alison (née Comish; 1914–2004), was an economist and the first woman to receive a PhD in economics from Iowa State College . Raised in an academic environment, two of his four siblings also became professors. Thorne's parents were members of
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#1732773034033972-474: A paper about the detection of gravitational waves , from a signal detected at 09.51 UTC on 14 September 2015 of two ~30 solar mass black holes merging about 1.3 billion light-years from Earth. Current executive director David Reitze announced the findings at a media event in Washington D.C., while executive director emeritus Barry Barish presented the first scientific paper of the findings at CERN to
1053-459: A professor of biokinesiology and physical therapy at USC , married in 1984. Thorne's research has principally focused on relativistic astrophysics and gravitation physics , with emphasis on relativistic stars , black holes and especially gravitational waves . He is perhaps best known to the public for his controversial theory that wormholes can conceivably be used for time travel. However, Thorne's scientific contributions, which center on
1134-638: A professor of theoretical physics in 1970, becoming one of the youngest full professors in the history of Caltech at age 30. He became the William R. Kenan, Jr. Professor in 1981, and the Feynman Professor of Theoretical Physics in 1991. He was an adjunct professor at the University of Utah from 1971 to 1998 and Andrew D. White Professor at Large at Cornell University from 1986 to 1992. In June 2009, he resigned his Feynman Professorship (he
1215-477: A short gamma-ray burst arrived at Earth from the direction of the Andromeda Galaxy . The prevailing explanation of most short gamma-ray bursts is the merger of a neutron star with either a neutron star or a black hole. LIGO reported a non-detection for GRB 070201, ruling out a merger at the distance of Andromeda with high confidence. Such a constraint was predicated on LIGO eventually demonstrating
1296-405: A third black hole merger, between objects of 31.2 and 19.4 solar masses, occurred on 4 January 2017 and was announced on 1 June 2017. Laura Cadonati was appointed the first deputy spokesperson. A fourth detection of a black hole merger, between objects of 30.5 and 25.3 solar masses, was observed on 14 August 2017 and was announced on 27 September 2017. In 2017, Weiss, Barish, and Thorne received
1377-438: Is introduced. If his results can be generalized, they would suggest that none of the supposed paradoxes formulated in time travel stories can actually be formulated at a precise physical level: that is, that any situation in a time travel story turns out to permit many consistent solutions. With Anna Żytkow , Thorne predicted the existence of red supergiant stars with neutron-star cores ( Thorne–Żytkow objects ). He laid
1458-726: Is known for his ability to convey the excitement and significance of discoveries in gravitation and astrophysics to both professional and lay audiences. His presentations on subjects such as black holes , gravitational radiation , relativity , time travel , and wormholes have been included in PBS shows in the U.S. and on the BBC in the United Kingdom. Thorne and Linda Jean Peterson married in 1960. Their children are Kares Anne and Bret Carter, an architect. Thorne and Peterson divorced in 1977. Thorne and his second wife, Carolee Joyce Winstein,
1539-587: Is now the Feynman Professor of Theoretical Physics, Emeritus) to pursue a career of writing and movie making. His first film project was Interstellar , on which he worked with Christopher Nolan and Jonathan Nolan . Throughout the years, Thorne has served as a mentor and thesis advisor to many leading theorists who now work on observational, experimental, or astrophysical aspects of general relativity. Approximately 50 physicists have received PhDs at Caltech under Thorne's personal mentorship. Thorne
1620-544: The COVID-19 pandemic halted operations. During the COVID shutdown, LIGO underwent a further upgrade in sensitivity, and observing run O4 with the new sensitivity began on 24 May 2023. LIGO's mission is to directly observe gravitational waves of cosmic origin. These waves were first predicted by Einstein's general theory of relativity in 1916, when the technology necessary for their detection did not yet exist. Their existence
1701-593: The Nobel Prize in Physics "for decisive contributions to the LIGO detector and the observation of gravitational waves." Weiss was awarded one-half of the total prize money, and Barish and Thorne each received a one-quarter prize. After shutting down for improvements, LIGO resumed operation on 26 March 2019, with Virgo joining the network of gravitational-wave detectors on 1 April 2019. Both ran until 27 March 2020, when
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#17327730340331782-631: The Westinghouse Science Talent Search as a senior at Logan High School . He received his BS in physics degree from the California Institute of Technology (Caltech) in 1962, and his master and PhD in physics from Princeton University in 1964 and 1965 under the supervision of John Archibald Wheeler with a doctoral dissertation entitled " Geometrodynamics of Cylindrical Systems". Thorne returned to Caltech as an associate professor in 1967 and became
1863-499: The charge diameter of a proton . The initial LIGO observatories were funded by the United States National Science Foundation (NSF) and were conceived, built and are operated by Caltech and MIT . They collected data from 2002 to 2010 but no gravitational waves were detected. The Advanced LIGO Project to enhance the original LIGO detectors began in 2008 and continues to be supported by
1944-560: The charge diameter of a proton . Equivalently, this is a relative change in distance of approximately one part in 10. A typical event which might cause a detection event would be the late stage inspiral and merger of two 10- solar-mass black holes, not necessarily located in the Milky Way galaxy, which is expected to result in a very specific sequence of signals often summarized by the slogan chirp, burst, quasi-normal mode ringing, exponential decay. In their fourth Science Run at
2025-477: The " membrane paradigm ", to the theory of black holes and used it to clarify the Blandford–Znajek mechanism by which black holes may power some quasars and active galactic nuclei . Thorne has investigated the quantum statistical mechanical origin of the entropy of a black hole. With his postdoc Wojciech Zurek, he showed that the entropy of a black hole is the logarithm of the number of ways that
2106-530: The 1960s, American scientists including Joseph Weber , as well as Soviet scientists Mikhail Gertsenshtein and Vladislav Pustovoit , conceived of basic ideas and prototypes of laser interferometry , and in 1967 Rainer Weiss of MIT published an analysis of interferometer use and initiated the construction of a prototype with military funding, but it was terminated before it could become operational. Starting in 1968, Kip Thorne initiated theoretical efforts on gravitational waves and their sources at Caltech , and
2187-482: The 1960s, and perhaps before that, there were papers published on wave resonance of light and gravitational waves. Work was published in 1971 on methods to exploit this resonance for the detection of high-frequency gravitational waves . In 1962, M. E. Gertsenshtein and V. I. Pustovoit published the very first paper describing the principles for using interferometers for the detection of very long wavelength gravitational waves. The authors argued that by using interferometers
2268-625: The 4 km detectors. It concluded in October 2010, and the disassembly of the original detectors began. After 2010, LIGO went offline for several years for a major upgrade, installing the new Advanced LIGO detectors in the LIGO Observatory infrastructures. The project continued to attract new members, with the Australian National University and University of Adelaide contributing to Advanced LIGO, and by
2349-421: The 4 km length to the far mirrors and back again, the two separate beams leave the arms and recombine at the beam splitter. The beams returning from two arms are kept out of phase so that when the arms are both in coherence and interference (as when there is no gravitational wave passing through), their light waves subtract, and no light should arrive at the photodiode . When a gravitational wave passes through
2430-461: The COVID-caused stop, and LIGO's O4 observing run started on 24 May 2023. LIGO projects a sensitivity goal of 160–190 Mpc for binary neutron star mergers (sensitivities: Virgo 80–115 Mpc, KAGRA greater than 1 Mpc). The LIGO concept built upon early work by many scientists to test a component of Albert Einstein 's theory of general relativity , the existence of gravitational waves. Starting in
2511-634: The Church of Jesus Christ of Latter-day Saints (LDS Church) and raised Thorne in the LDS faith, though he now describes himself as atheist . Regarding his views on science and religion, Thorne has stated: "There are large numbers of my finest colleagues who are quite devout and believe in God .... There is no fundamental incompatibility between science and religion. I happen to not believe in God." Thorne rapidly excelled at academics early in life, winning recognition in
LIGO - Misplaced Pages Continue
2592-576: The LIGO Hanford Observatory, on the DOE Hanford Site ( 46°27′18.52″N 119°24′27.56″W / 46.4551444°N 119.4076556°W / 46.4551444; -119.4076556 ), located near Richland, Washington . These sites are separated by 3,002 kilometers (1,865 miles) straight line distance through the earth, but 3,030 kilometers (1,883 miles) over the surface. Since gravitational waves are expected to travel at
2673-444: The LIGO and Virgo collaborations announced the first observation of gravitational waves . The signal, named GW150914 , was recorded on 14 September 2015, just two days after Advanced LIGO started collecting data following the upgrade. It matched the predictions of general relativity for the inward spiral and merger of a pair of black holes and subsequent ringdown of the resulting single black hole. The observations demonstrated
2754-411: The LIGO detector and test facilities. The LIGO Scientific Collaboration is a forum for organizing technical and scientific research in LIGO. It is a separate organization from LIGO Laboratory with its own oversight. Barish appointed Weiss as the first spokesperson for this scientific collaboration. Initial LIGO operations between 2002 and 2010 did not detect any gravitational waves. In 2004, under Barish,
2835-564: The LIGO detector and the observation of gravitational waves". Observations are made in "runs". As of January 2022, LIGO has made three runs (with one of the runs divided into two "subruns"), and made 90 detections of gravitational waves. Maintenance and upgrades of the detectors are made between runs. The first run, O1, which ran from 12 September 2015 to 19 January 2016, made the first three detections, all black hole mergers. The second run, O2, which ran from 30 November 2016 to 25 August 2017, made eight detections: seven black hole mergers and
2916-526: The LIGO that cannot be developed on the basis of experiment and he gives advice on data analysis algorithms by which the waves will be sought. He has provided theoretical support for LIGO, including identifying gravitational wave sources that LIGO should target, designing the baffles to control scattered light in the LIGO beam tubes, and – in collaboration with Vladimir Braginsky 's (Moscow, Russia) research group – inventing quantum nondemolition designs for advanced gravity-wave detectors and ways to reduce
2997-399: The NSF funded the study of a large interferometer led by MIT (Paul Linsay, Peter Saulson , Rainer Weiss), and the following year, Caltech constructed a 40-meter prototype (Ronald Drever and Stan Whitcomb). The MIT study established the feasibility of interferometers at a 1-kilometer scale with adequate sensitivity. Under pressure from the NSF, MIT and Caltech were asked to join forces to lead
3078-793: The NSF, with important contributions from the United Kingdom's Science and Technology Facilities Council , the Max Planck Society of Germany, and the Australian Research Council . The improved detectors began operation in 2015. The detection of gravitational waves was reported in 2016 by the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration with the international participation of scientists from several universities and research institutions. Scientists involved in
3159-548: The Virgo Collaboration. Unlike the black hole mergers which are only detectable gravitationally, GW170817 came from the collision of two neutron stars and was also detected electromagnetically by gamma ray satellites and optical telescopes. The third run (O3) began on 1 April 2019 and was planned to last until 30 April 2020; in fact it was suspended in March 2020 due to COVID-19 . On 6 January 2020, LIGO announced
3240-573: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.133 via cp1102 cp1102, Varnish XID 546726961 Upstream caches: cp1102 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 05:50:34 GMT Kip Thorne Kip Stephen Thorne (born June 1, 1940) is an American theoretical physicist and writer known for his contributions in gravitational physics and astrophysics . Along with Rainer Weiss and Barry C. Barish , he
3321-429: The beams will cause the light currently in the cavity to become very slightly out of phase (antiphase) with the incoming light. The cavity will therefore periodically get very slightly out of coherence and the beams, which are tuned to destructively interfere at the detector, will have a very slight periodically varying detuning. This results in a measurable signal. After an equivalent of approximately 280 trips down
LIGO - Misplaced Pages Continue
3402-525: The detection of what appeared to be gravitational ripples from a collision of two neutron stars, recorded on 25 April 2019, by the LIGO Livingston detector. Unlike GW170817, this event did not result in any light being detected. Furthermore, this is the first published event for a single-observatory detection, given that the LIGO Hanford detector was temporarily offline at the time and the event
3483-436: The effective path length of laser light in the arm from 4 km to approximately 1,200 km. The power of the light field in the cavity is 100 kW. When a gravitational wave passes through the interferometer, the spacetime in the local area is altered. Depending on the source of the wave and its polarization, this results in an effective change in length of one or both of the cavities. The effective length change between
3564-407: The effort to detect gravitational waves in the 1960s through his work on resonant mass bar detectors . Bar detectors continue to be used at six sites worldwide. By the 1970s, scientists including Rainer Weiss realized the applicability of laser interferometry to gravitational wave measurements. Robert Forward operated an interferometric detector at Hughes in the early 1970s. In fact as early as
3645-555: The end of 2004, the LIGO detectors demonstrated sensitivities in measuring these displacements to within a factor of two of their design. During LIGO's fifth Science Run in November 2005, sensitivity reached the primary design specification of a detectable strain of one part in 10 over a 100 Hz bandwidth. The baseline inspiral of two roughly solar-mass neutron stars is typically expected to be observable if it occurs within about 8 million parsecs (26 × 10 ^ ly ), or
3726-437: The existence of binary stellar-mass black hole systems and the first observation of a binary black hole merger. On 15 June 2016, LIGO announced the detection of a second gravitational wave event, recorded on 26 December 2015, at 3:38 UTC. Analysis of the observed signal indicated that the event was caused by the merger of two black holes with masses of 14.2 and 7.5 solar masses, at a distance of 1.4 billion light years. The signal
3807-428: The exterior of a slowly and rigidly rotating, stationary and axially symmetric body. Thorne has also theoretically predicted the existence of universally antigravitating " exotic matter " – the element needed to accelerate the expansion rate of the universe, keep traversable wormhole "Star Gates" open and keep timelike geodesic free float " warp drives " working. With Clifford Will and others of his students, he laid
3888-550: The first neutron star merger . The third run, O3, began on 1 April 2019; it was divided into O3a, from 1 April to 30 September 2019, and O3b, from 1 November 2019 until it was suspended on 27 March 2020 due to COVID-19 . The O3 run included the first detection of the merger of a neutron star with a black hole. The gravitational wave observatories LIGO, Virgo in Italy, and KAGRA in Japan are coordinating to continue observations after
3969-420: The foundations for the theoretical interpretation of experimental tests of relativistic theories of gravity – foundations on which Will and others then built. As of 2005 , Thorne was interested in the origin of classical space and time from the quantum foam of quantum gravity theory. Thorne has written and edited books on topics in gravitational theory and high-energy astrophysics . In 1973, he co-authored
4050-521: The foundations for the theory of pulsations of relativistic stars and the gravitational radiation they emit. With James Hartle , Thorne derived from general relativity the laws of motion and precession of black holes and other relativistic bodies, including the influence of the coupling of their multipole moments to the spacetime curvature of nearby objects, as well as writing down the Hartle-Thorne metric , an approximate solution which describes
4131-664: The full length interferometers above 200 Hz but only half as good at low frequencies. During the same era, Hanford retained its original passive seismic isolation system due to limited geologic activity in Southeastern Washington. The parameters in this section refer to the Advanced LIGO experiment. The primary interferometer consists of two beam lines of 4 km length which form a power-recycled Michelson interferometer with Gires–Tournois etalon arms. A pre-stabilized 1064 nm Nd:YAG laser emits
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#17327730340334212-651: The funding and groundwork were laid for the next phase of LIGO development (called "Enhanced LIGO"). This was followed by a multi-year shut-down while the detectors were replaced by much improved "Advanced LIGO" versions. Much of the research and development work for the LIGO/aLIGO machines was based on pioneering work for the GEO600 detector at Hannover, Germany. By February 2015, the detectors were brought into engineering mode in both locations. In mid-September 2015, "the world's largest gravitational-wave facility" completed
4293-417: The general nature of space , time, and gravity , span the full range of topics in general relativity. Thorne's work has dealt with the prediction of gravitational wave strengths and their temporal signatures as observed on Earth. These "signatures" are of great relevance to LIGO (Laser Interferometer Gravitational Wave Observatory), a multi-institution gravitational wave experiment for which Thorne has been
4374-504: The hole could have been made. With Igor Novikov and Don Page , he developed the general relativistic theory of thin accretion disks around black holes, and using this theory he deduced that with a doubling of its mass by such accretion a black hole will be spun up to 0.998 of the maximum spin allowed by general relativity, but not any farther. This is probably the maximum black-hole spin allowed in nature. Thorne and his co-workers at Caltech conducted scientific research on whether
4455-409: The interferometer, the distances along the arms of the interferometer are shortened and lengthened, causing the beams to become slightly less out of phase. This results in the beams coming in phase, creating a resonance , hence some light arrives at the photodiode and indicates a signal. Light that does not contain a signal is returned to the interferometer using a power recycling mirror, thus increasing
4536-577: The largest overall funded NSF project in history. The project broke ground in Hanford, Washington in late 1994 and in Livingston, Louisiana in 1995. As construction neared completion in 1997, under Barish's leadership two organizational institutions were formed, LIGO Laboratory and LIGO Scientific Collaboration (LSC). The LIGO laboratory consists of the facilities supported by the NSF under LIGO Operation and Advanced R&D; this includes administration of
4617-490: The laws of physics permit space and time to be multiply connected (can there exist classical, traversable wormholes and "time machines"?). With Sung-Won Kim, Thorne identified a universal physical mechanism (the explosive growth of vacuum polarization of quantum fields ), that may always prevent spacetime from developing closed timelike curves (i.e., prevent backward time travel ). With Mike Morris and Ulvi Yurtsever , he showed that traversable wormholes can exist in
4698-511: The most serious kind of noise in advanced detectors: thermoelastic noise . With Carlton M. Caves , Thorne invented the back-action-evasion approach to quantum nondemolition measurements of the harmonic oscillators – a technique applicable both in gravitational wave detection and quantum optics . On February 11, 2016, a team of four physicists representing the LIGO Scientific Collaboration , announced that in September 2015, LIGO recorded
4779-587: The one at the Livingston Observatory. During the Initial and Enhanced LIGO phases, a half-length interferometer operated in parallel with the main interferometer. For this 2 km interferometer, the Fabry–Pérot arm cavities had the same optical finesse, and, thus, half the storage time as the 4 km interferometers. With half the storage time, the theoretical strain sensitivity was as good as
4860-584: The physics community. On 2 May 2016, members of the LIGO Scientific Collaboration and other contributors were awarded a Special Breakthrough Prize in Fundamental Physics for contributing to the direct detection of gravitational waves. On 16 June 2016 LIGO announced a second signal was detected from the merging of two black holes with 14.2 and 7.5 times the mass of the Sun. The signal was picked up on 26 December 2015, at 3:38 UTC. The detection of
4941-483: The point where detection of gravitational waves —of significant astrophysical interest—is now possible. In August 2002, LIGO began its search for cosmic gravitational waves. Measurable emissions of gravitational waves are expected from binary systems (collisions and coalescences of neutron stars or black holes ), supernova explosions of massive stars (which form neutron stars and black holes), accreting neutron stars, rotations of neutron stars with deformed crusts, and
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#17327730340335022-446: The power of the light in the arms. In actual operation, noise sources can cause movement in the optics, producing similar effects to real gravitational wave signals; a great deal of the art and complexity in the instrument is in finding ways to reduce these spurious motions of the mirrors. Background noise and unknown errors (which happen daily) are in the order of 10, while gravitational wave signals are around 10. After noise reduction,
5103-413: The primary configuration. This interferometer was successfully upgraded in 2004 with an active vibration isolation system based on hydraulic actuators providing a factor of 10 isolation in the 0.1–5 Hz band. Seismic vibration in this band is chiefly due to microseismic waves and anthropogenic sources (traffic, logging, etc.). The LIGO Hanford Observatory houses one interferometer, almost identical to
5184-578: The problem, he proved that it was impossible for cylindrical magnetic field lines to implode . Why won't a cylindrical bundle of magnetic field lines implode, while spherical stars will implode under their own gravitational force? Thorne tried to explore the theoretical ridge between these two phenomena. He eventually determined that the gravitational force can overcome all interior pressure only when an object has been compressed in all directions. To express this realization, Thorne proposed his hoop conjecture , which describes an imploding star turning into
5265-484: The project and the analysis of the data for gravitational-wave astronomy are organized by the LSC, which includes more than 1000 scientists worldwide, as well as 440,000 active Einstein@Home users as of December 2016. LIGO is the largest and most ambitious project ever funded by the NSF. In 2017, the Nobel Prize in Physics was awarded to Rainer Weiss , Kip Thorne and Barry C. Barish "for decisive contributions to
5346-435: The project, resulting in the withholding of funds until they formally froze spending in 1993. In 1994, after consultation between relevant NSF personnel, LIGO's scientific leaders, and the presidents of MIT and Caltech, Vogt stepped down and Barry Barish (Caltech) was appointed laboratory director, and the NSF made clear that LIGO had one last chance for support. Barish's team created a new study, budget, and project plan with
5427-653: The remnants of gravitational radiation created by the birth of the universe . The observatory may, in theory, also observe more exotic hypothetical phenomena, such as gravitational waves caused by oscillating cosmic strings or colliding domain walls . LIGO operates two gravitational wave observatories in unison: the LIGO Livingston Observatory ( 30°33′46.42″N 90°46′27.27″W / 30.5628944°N 90.7742417°W / 30.5628944; -90.7742417 ) in Livingston, Louisiana , and
5508-575: The science behind Christopher Nolan's film Interstellar ; Nolan wrote the foreword to the book. In September 2017, Thorne and Roger D. Blandford published Modern Classical Physics: Optics, Fluids, Plasmas, Elasticity, Relativity, and Statistical Physics , a graduate-level textbook covering the six major areas of physics listed in the title. Thorne's articles have appeared in publications such as: Thorne has published more than 150 articles in scholarly journals. Thorne has been elected to: He has been recognized by numerous awards including: He has been
5589-438: The sensitivity can be 10 to 10 times better than by using electromechanical experiments. Later, in 1965, Braginsky extensively discussed gravitational-wave sources and their possible detection. He pointed out the 1962 paper and mentioned the possibility of detecting gravitational waves if the interferometric technology and measuring techniques improved. Since the early 1990s, physicists have thought that technology has evolved to
5670-540: The signature of two black holes colliding 1.3 billion light-years away. This recorded detection was the first direct observation of the fleeting chirp of a gravitational wave and confirmed a prediction of the general theory of relativity. While studying for his PhD at Princeton University, his mentor John Wheeler assigned him a problem to think about: find out whether or not a cylindrical bundle of repulsive magnetic field lines will implode under its own attractive gravitational force. After several months wrestling with
5751-659: The speed of light, this distance corresponds to a difference in gravitational wave arrival times of up to ten milliseconds. Through the use of trilateration , the difference in arrival times helps to determine the source of the wave, especially when a third similar instrument like Virgo , located at an even greater distance in Europe, is added. Each observatory supports an L-shaped ultra high vacuum system, measuring four kilometers (2.5 miles) on each side. Up to five interferometers can be set up in each vacuum system. The LIGO Livingston Observatory houses one laser interferometer in
5832-541: The structure of spacetime only if they are threaded by quantum fields in quantum states that violate the averaged null energy condition (i.e. have negative renormalized energy spread over a sufficiently large region). This has triggered research to explore the ability of quantum fields to possess such extended negative energy . Recent calculations by Thorne indicate that simple masses passing through traversable wormholes could never engender paradoxes – there are no initial conditions that lead to paradox once time travel
5913-616: The textbook Gravitation with Charles Misner and John Wheeler ; that according to John C. Baez and Chris Hillman, is one of the great scientific books of all time and has inspired two generations of students. In 1994, he published Black Holes and Time Warps: Einstein's Outrageous Legacy , a book for non-scientists for which he received numerous awards. This book has been published in six languages, and editions in Chinese, Italian, Czech, and Polish are in press. In 2014, Thorne published The Science of Interstellar in which he explains
5994-550: The time the LIGO Laboratory started the first observing run 'O1' with the Advanced LIGO detectors in September 2015, the LIGO Scientific Collaboration included more than 900 scientists worldwide. The first observing run operated at a sensitivity roughly three times greater than Initial LIGO, and a much greater sensitivity for larger systems with their peak radiation at lower audio frequencies. On 11 February 2016,
6075-715: The vicinity of the Local Group , averaged over all directions and polarizations. Also at this time, LIGO and GEO 600 (the German-UK interferometric detector) began a joint science run, during which they collected data for several months. Virgo (the French-Italian interferometric detector) joined in May 2007. The fifth science run ended in 2007, after extensive analysis of data from this run did not uncover any unambiguous detection events. In February 2007, GRB 070201,
6156-598: Was awarded the 2017 Nobel Prize in Physics for his contributions to the LIGO detector and the observation of gravitational waves . A longtime friend and colleague of Stephen Hawking and Carl Sagan , he was the Richard P. Feynman Professor of Theoretical Physics at the California Institute of Technology (Caltech) until 2009 and speaks of the astrophysical implications of the general theory of relativity . He continues to do scientific research and scientific consulting,
6237-711: Was convinced that gravitational wave detection would eventually succeed. Prototype interferometric gravitational wave detectors (interferometers) were built in the late 1960s by Robert L. Forward and colleagues at Hughes Research Laboratories (with mirrors mounted on a vibration isolated plate rather than free swinging), and in the 1970s (with free swinging mirrors between which light bounced many times) by Weiss at MIT, and then by Heinz Billing and colleagues in Garching Germany, and then by Ronald Drever , James Hough and colleagues in Glasgow, Scotland. In 1980,
6318-496: Was indirectly confirmed when observations of the binary pulsar PSR 1913+16 in 1974 showed an orbital decay which matched Einstein's predictions of energy loss by gravitational radiation. The Nobel Prize in Physics 1993 was awarded to Hulse and Taylor for this discovery. Direct detection of gravitational waves had long been sought. Their discovery has launched a new branch of astronomy to complement electromagnetic telescopes and neutrino observatories. Joseph Weber pioneered
6399-514: Was named GW151226 . The second observing run (O2) ran from 30 November 2016 to 25 August 2017, with Livingston achieving 15–25% sensitivity improvement over O1, and with Hanford's sensitivity similar to O1. In this period, LIGO saw several further gravitational wave events: GW170104 in January; GW170608 in June; and five others between July and August 2017. Several of these were also detected by
6480-435: Was routinely rejected until 1991, when the U.S. Congress agreed to fund LIGO for the first year for $ 23 million. However, requirements for receiving the funding were not met or approved, and the NSF questioned the technological and organizational basis of the project. By 1992, LIGO was restructured with Drever no longer a direct participant. Ongoing project management issues and technical concerns were revealed in NSF reviews of
6561-537: Was too faint to be visible in Virgo's data. The fourth observing run (O4) was planned to start in December 2022, but was postponed until 24 May 2023. O4 is projected to continue until February 2025. As of O4, the interferometers are operating at a sensitivity of 155-175 Mpc, within the design sensitivity range of 160-190 Mpc for binary neutron star events. Physics Too Many Requests If you report this error to
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