Research highlights in CQG and PRD

Friday, August 12, 2016

Some papers from our group were recently selected as research highlights in Classical and Quantum Gravity (CQG) and Physical Review D (PRD).

CQG selected two papers by the LIGO collaboration (a review of Advanced LIGO and a paper on detector characterization) as well as our review on tests of general relativity for their annual 2015 Highlights collection.

Today, our paper on astrophysical applications of the post-Tolman-Oppenheimer-Volkoff approximation was published in PRD as an Editor’s Suggestion.

ICTS Summer School Lectures

Wednesday, August 3, 2016

Over the last three years the International Center for Theoretical Sciences (Tata Institute of Fundamental Research, Bangalore, India) has been organizing summer/winter schools on various topics in gravitational-wave (GW) physics and astronomy. Each school from this series targeted a particular sub-area (theory, experiment, data science, etc) of GW science. This year’s school has special significance because of the first direct detection of GWs by the LIGO observatories. The school involves three graduate-level courses in theoretical GW physics: Gravity: Newtonian, post-Newtonian, Relativistic by Clifford M. Will; Gravitational Astronomy by Bangalore S. Sathyaprakash; and Black Hole Perturbation Theory by Emanuele Berti. Videos of the lectures and lecture materials can be found here.

L3ST Study Interim Report

Monday, August 1, 2016

The L3 Study Team Interim Report has been released and posted on the PCOS website. The L3 Study Team was charged to provide an analysis of potential US hardware contributions to the ESA-led L3 Gravitational Wave mission and an assessment of their consequences on cost, risk, and science return. Some highlights from the report:

• The science case for a space-based GW observatory, endorsed by both the 2010 Decadal Survey and ESA’s 2013 Cosmic Visions process, remains compelling. Realizing a mission that fully delivers this science in a timely fashion and with low risk should be the primary objective of US participation in L3.

• The L3ST concurs with the ESA’s GOAT report that meaningful participation of the US community in the design, development, and operation of L3 will result in a mission that is more technically robust and more scientifically capable.

• US contribution of central elements of the payload is an effective way to enable meaningful participation and provide impact on, and insight into, the final flight design.

• The US has strengths in a broad range of technologies relevant to L3. Opportunities should be sought to employ all of these strengths in the partnership regardless of the specific hardware items delivered.

A conclusion of our analysis is that multiple viable options of US participation in L3 exist, each with a different mix of cost, risk, and impact. While it is likely that the US will only contribute a subset of these items to the final partnership, continuing some level of development across the entire portfolio is an effective strategy to reduce overall mission risk as well as provide additional insight to the US science and technology communities.

“Unifying Tests of General Relativity” Workshop

Tuesday, June 21, 2016

Precision tests of general relativity are being developed enthusiastically on many fronts, but there is not enough communication between researchers working across different distance scales — the observables, parametrization frameworks, and even alternative theories are different and hard to compare. The Burke Institute at Caltech is sponsoring a workshop on these topics (Unifying Tests of General Relativity) that will take place on July 19-21, 2016. The workshop will focus on developing a sort of “lingua franca” for those working on cosmological and strong-field tests of gravity, the eventual aim being the ability to usefully interpret observational results across the two fields. The workshop is organized by Emanuele Berti, Phil Bull, Sean Carroll, Yanbei Chen, Olivier Doré, Jérôme Gleyzes and Leo C. Stein.

Update [7/22/2016]: here is a group photo from the workshop!
BurkeGroup.jpg

LIGO detects second pair of colliding black holes

Wednesday, June 15, 2016

The two LIGO gravitational wave detectors in Hanford Washington and Livingston Louisiana have caught a second robust signal from two black holes in their final orbits and then their coalescence into a single black hole. Read about the discovery and the contribution of the UM LIGO team to it on UM news.