New Messengers and New Physics
This week we review the second of the three main focus areas the Astro2020 decadal survey: “New Messengers and New Physics”.
“Messengers” here refers to the type of signal that is being observed. Usually astronomers collect light - from the radio wave variety all the way up the spectrum to X-rays. These days more options are available.
The technology behind Neutrino and Gravitational Wave telescopes has matured, and with it comes the opportunity for multichannel astronomy.
Neutrino telescopes - like the famous IceCube experiment at the South Pole - seek to measure some of the hardest particles to detect in the universe. Neutrinos are plentiful, but rarely interact, so these telescopes are enormous. We’ve got a write up and a podcast about them over at our Field Guide to Particle Physics.
Neutrinos are produced in copious amounts during Supernovae, and can be used in conjunction with telescopes to get a complimentary view of these same events. Supernovae are some of the brightest events in the universe - and have been used to calibrate distances and study the late-time accelerated expansion of our universe.
Gravitational Wave observatories - like those apart of the LIGO and VIRGO collaborations - are the newest astronomical channel to come online. Using orthogonal, kilometer-sized lasers to look for the subtle interference generated by the distortion of spacetime, these facilities can measure high frequency gravitational waves put out by distant, astrophysical events.
Gravitational waves are collective oscillations in the very fabric of spacetime. Those waves that get observed directly on earth are generated by some of the most powerful events in our universe: mergers between and of black holes and neutron stars.
The very existence of gravitational waves confirms their prediction by general relativity, and implies the existence of another curious phenomena at the other end of the gravitational wave spectrum, namely the Memory Effect. Katie McCormick at Quanta Magazine has a new essaywhich explains this subtle - and exciting effect.
