Timeline of gravitational physics and relativity

Einstein's mass-energy equation in a 1912 manuscript. He originally used instead of to denote energy.

The following is a timeline of gravitational physics and general relativity.

Before 1500

1500s

1600s

Geometric diagram for Newton's proof of Kepler's second law.

1700s

Lagrange points

1800s

1900s

The U.S. Navy's nuclear-powered Task Force 1 underway for Operation Sea Orbit in the Mediterranean, 1964.

1910s

Einstein's 1911 argument for gravitational redshift

1920s

1930s

The Einstein Cross is an example of gravitational lensing at work. This one was discovered in 1985.

1940s

1950s

1960s

1970s

1980s

Variations in the temperature of the cosmic microwave background measured by the COBE satellite.
Variations in the temperature of the cosmic microwave background measured by the COBE satellite. The plane of the Milky Way Galaxy is horizontal across the middle of each picture.

1990s

Parameter space of various approximation techniques in general relativity

2000s

2010s

Improving cosmological measurements by three different satellites
  • 2010 – A team at the U.S. National Institute for Standards and Technology (NIST) verifies relativistic time dilation using optical atomic clocks.
  • 2011 – Wilkinson Microwave Anisotropy Probe (WMAP) finds no statistically significant deviations from the ΛCDM model of cosmology.
  • 2012 – Hubble Ultra-Deep Field image released. It was created using data collected by the Hubble Space Telescope between 2003 and 2004.
  • 2013 – NuSTAR and XMM-Newton measure the spin of the supermassive black hole at the center of the galaxy NGC 1365.
  • 2015 – Advanced LIGO reports the first direct detections of gravitational waves, GW150914 and GW151226, mergers of stellar-mass black holes. Gravitational-wave astronomy is born. No deviations from general relativity were found.
  • 2017 – LIGO-VIRGO collaboration detects gravitational waves emitted by a neutron-star binary, GW170817. The Fermi Gamma-ray Space Telescope and the International Gamma-ray Astrophysics Laboratory (INTEGRAL) unambiguously detect the corresponding gamma-ray burst. LIGO-VIRGO and Fermi constrain the difference between the speed of gravity and the speed of light in vacuum to 10−15. This marks the first time electromagnetic and gravitational waves are detected from a single source, and give direct evidence that some (short) gamma-ray bursts are due to colliding neutron stars.
  • 2017 – Multi-messenger astronomy reveals neutron-star mergers to be responsible for the nucleosynthesis of some heavy elements, such as strontium, via the rapid-neutron capture or r-process.
  • 2017 – MICROSCOPE satellite experiment verifies the principle of equivalence to 10−15 in terms of the Eötvös ratio . The final report is published in 2022.
  • 2017 – Principle of equivalence tested to 10−9 for atoms in a coherent state of superposition.
  • 2017 – Scientists begin using gravitational-wave sources as "standard sirens" to measure the Hubble constant, finding its value to be broadly in line with the best estimates of the time. Refinements of this technique will help resolve discrepancies between the different methods of measurements.
  • 2017 – Neutron Star Interior Composition Explorer (NICER) arrives on the International Space Station.
  • 2017-18 – Georgios Moschidis proves the instability of the anti-de Sitter spacetime.
  • 2018 – Final paper by the Planck satellite collaboration. Planck operated between 2009 and 2013.
  • 2018 – Mihalis Dafermos and Jonathan Luk disprove the strong cosmic censorship hypothesis for the Cauchy horizon of an uncharged, rotating black hole.
  • 2018 – European Southern Observatory (ESO) observes gravitational redshift of radiation emitted by matter orbiting Sagittarius A*, the central supermassive black hole of the Milky Way, and verifies the innermost stable circular orbit for that object.
  • 2018 – Advanced LIGO-VIRGO collaboration constrains equations of state for a neutron star using GW170817.
  • 2018 – Luciano Rezzolla, Elias R. Most, and Lukas R. Weih used gravitational-wave data from GW170817 constrain the possible maximum mass for a neutron star to around 2.17 solar masses.
  • 2018 – Kris Pardo, Maya Fishbach, Daniel Holz, and David Spergel limit the number of spacetime dimensions through which gravitational waves can propagate to 3 + 1, in line with general relativity and ruling out models that allow for "leakage" to higher dimensions of space. Analyses of GW170817 have also ruled out many other alternatives to general relativity, and proposals for dark energy.
  • 2018 – Two different experimental teams report highly precise values of Newton's gravitational constant that slightly disagree.
  • 2019 – Event Horizon Telescope (EHT) releases an image of supermassive black hole M87*, and measures its mass and shadow. Results are confirmed in 2024.
  • 2019 – Advanced LIGO and VIRGO detect GW190814, the collision of a 26-solar-mass black hole and a 2.6-solar-mass object, either an extremely heavy neutron star or a very light black hole. This is the largest mass gap seen in a gravitational-wave source to-date.

2020s

The size of Sagittarius A* is smaller than the orbit of Mercury.

See also

References

Uses material from the Wikipedia article Timeline of gravitational physics and relativity, released under the CC BY-SA 4.0 license.