LIGO’s gravitational wave detection is Physics World 2016 Breakthrough of the Year

by Clifford M Will.

Physics World breakthrough of the year prize

The Physics World 2016 Breakthrough of the Year goes to the LIGO Scientific Collaboration for their revolutionary, first ever direct observations of gravitational waves.

Long awaited direct detection of Einstein’s gravitational-waves tops Physics World’s list of the 10 key breakthroughs in physics in 2016

It give me great pleasure to report that the LIGO Scientific Collaboration are to receive Physics World’s Breakthrough of the year award.  At the end of every year, the Physics World editorial team reveals what it believes to be the top 10 research breakthroughs for the past year and one of these is selected to be the Physics World Breakthrough of the year.

In recognition of this achievement, the Physics World team have created a short documentary movie with the assistance of members of the LIGO collaboration from Cardiff University.

The video features Samantha Usman, who recently wrote an excellent CQG+ entry about the discovery.
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Highlights of 2015

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity

The latest CQG Highlights are now available to view.  These papers represent the most interesting and important work published in CQG in 2015.  They were selected by the CQG Editorial Board and approved at CQG’s recent annual board meeting in London.

This year marks a break from the process used in past years.  CQG Highlights used to be Continue reading

The world we live in – #GR21

This is the second in a series of posts timed to coincide with the GR21 meeting. Keep an eye on CQG+ this week, for more posts on gravitational waves, the CQG Highlights and more.

Adam Day and the NYT building

Adam Day admiring the view from the top of the Rockefeller Center in NYC

I once had the experience of trying to find journal articles in an old bricks and mortar library. I spent a whole afternoon scouring a few thousand journal copies (and never did find what I was looking for). Information was scarce in those days and there were few ways to get it.

Watching scholarly communication develop since then has been interesting. In many ways, it’s now much easier to find papers – especially when you know exactly what you want to read. However, readers increasingly now find Continue reading

What makes a CQG Paper different?

Adam Day

Adam Day is the Executive Editor of Classical and Quantum Gravity

CQG is known for its high standard of peer review. We’re extremely grateful to everyone in the gravitational physics community who has helped to build and maintain this standard over the years. Detailing everything that goes into this would go beyond the scope of a single blog post. Nevertheless, I thought it might be helpful to you if I say a few words about what we are looking for in referees’ reports here at the CQG editorial office.

If you have refereed for CQG lately, you will have seen Continue reading

2016 Bergmann-Wheeler Thesis Prize winner: Lisa Glaser

Lisa Glaser

Lisa Glaser is currently a Research Fellow at University of Nottingham, and will (from September 2016) join Renate Loll’s group at the Radboud Universitet in Nijmegen with a Marie Skłodowska-Curie fellowship to explore renormalisation in discrete theories of quantum gravity.
You can follow her on Twitter. 

1. Tell us about your thesis

During my Ph.D. I worked on causal dynamical triangulations and causal set theory. While these approaches are very different at first sight, upon closer examination they show important similarities. In both theories we try to solve the path integral over geometries by introducing a regularisation.

In causal dynamical triangulations the regularisation are simplices, which scale away in the continuum limit, while causal set theory proposes a fundamental smallest volume of space-time events. Another similarity is that both of these theories try to incorporate the Lorentzian structure of space-time into the theory. In causal dynamical triangulations this is implemented through a Continue reading

Gravitational waves detected. Einstein was right … again

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity

As if celebrating the 100th birthday of general relativity weren’t enough, the LIGO-Virgo collaboration has provided “the icing on the cake” with today’s announcement of the first direct detection of gravitational waves. At press conferences in the USA and Europe, and in a paper in Physical Review Letters published afterward, the team announced the detection of a signal from a system of two merging black holes.

The signal arrived on 14 September, 2015 (its official designation is GW150914), and was detected by both the Hanford and Livingston advanced detectors of the LIGO observatory (the advanced Virgo instrument in Italy is not yet online). It was detected first by Continue reading

Some memories from meeting Einstein in 1951 – 1952

Yvonne Choquet-Bruhat

Yvonne Choquet-Bruhat is a French mathematician and physicist, renowned for her pioneering work on the initial value problem of General Relativity. Her work was one of the “Milestones of General Relativity” featured in a recent CQG focus issue. She has been on the faculty of the University of Marseille, the University of Reims and the University Pierre-et-Marie-Curie in Paris. She was the first woman to be elected to the French Academy of Sciences and is a Grand Croix of the Legion of Honour of France. She is also an elected member of the American Academy of Arts and Sciences. This reminiscence of Einstein was presented at the conference “A Century of General Relativity” held in Berlin, 30 November to 5 December, 2015. This image of Yvonne Choquet-Bruhat has been obtained from Wikipedia where it was made available by Momotaro under a CC-BY-SA 2.0 license. It is included within this article on that basis and attributed to Oberwolfach Photo Collection. 

I met Einstein in 1951 at the Institute for Advanced Study in Princeton. I was making there a postdoctoral stay, as assistant to the great mathematician Jean Leray, a part-time permanent professor at the IAS. I had defended a thesis on General Relativity under the official direction of André Lichnerowicz, but it was Jean Leray who had encouraged me to attack the problem of the existence of solutions of the Einstein equations taking given initial values, without assuming their analyticity. When I told Lichnerowicz about Leray’s suggestion, he said “it is too difficult for a beginner”. In fact it was not so difficult. In harmonic coordinates, called then “isotherm”, introduced by Lanczos, DeDonder and Georges Darmois, the Einstein equations in vacuum look like a system of quasidiagonal, quasilinear system of second order partial differential equations hyperbolic for a Lorentzian metric. I found by chance an article written in French by Continue reading

General Relativity turns 100!

Clifford M Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity, Distinguished Professor of Physics at the University of Florida, Chercheur Associé at the Institut d’Astrophysique de Paris, and James McDonnell Professor of Space Sciences Emeritus at Washington University in St. Louis.

November 4, 1915 was a Thursday. It was the day that Albert Einstein gave the first of a series of four weekly lectures to the Prussian Academy of Sciences in Berlin. His life was a mess. He was separated from his wife Mileva, who had moved to Zurich taking his sons with her. He was having an affair with his second cousin Elsa. He was working night and day, was barely eating, and was suffering from stomach pains. He had agreed to give these lectures to present his theory of gravity but he still didn’t have it. To make matters worse, David Hilbert was racing to find the field equations first, and Einstein feared he would be beaten. Yet by the third lecture, Continue reading

CQG Highlights now live

Adam Day

Adam Day is the Publisher of Classical and Quantum Gravity and CQG+.  Follow him on Twitter and Facebook.

I am delighted to announce the CQG Highlights of 2014-2015.  The collection is free to read until 31 December 2016.

How are the Highlights selected?

Each summer, the Editorial Board of Classical and Quantum Gravity convene in London for the journal’s annual Editorial Board meeting. In advance of the meeting, Board members submit proposed Highlights published in CQG in the previous 12 months. That list is discussed in the meeting: some papers are added to the list, others removed. Ultimately, the Highlights are approved by the Editor-in-Chief.

It’s a thorough process and the result is perhaps the best recognized collection in gravitational physics.

I would like to congratulate every author whose work was selected to be a Highlight this year and invite all authors to publish with CQG. A paper submitted today could be a Highlight by this time next year.

CQG LettersDon’t forget that you can now publish Letters in CQG. CQG Letters are required to be high quality, so they stand a good chance of being selected as Highlights.  CQG Letters will also feature in promotions here at CQG+. Submit your CQG Letter today.

CQG Letters – open for submission

Clifford Will

Clifford Will is the Editor-in-Chief of Classical and Quantum Gravity

I am very pleased to announce the launch of CQG’s new Letters section.

In a recent survey of CQG’s authors and readers, we identified a strong desire among gravitational physicists for CQG to launch this section.

The Letter article type is now available and I invite you to submit your next Letter to the journal.

The benefits

CQG’s peer review will ensure the best possible consideration for your Letter – certifying, not just Continue reading