Update: talks now available at links below. 

The next London Cosmology Discussion Meeting will be held next week at 1400 on Thursday 29th October at the Royal Astronomical Society.

There is no overall theme, but we have two theory talks related to field theory for inflation and dark energy and two talks focusing more on methods for and analysis of data.

The talks and the speakers will be the following:

—-
Theory:
14:00 – 14:25: Soft limits in multifield inflation — David Mulryne (QMUL)
14:25 – 14:50: Effective field theory in cosmology — Raquel Ribeiro (QMUL)
14:50 – 15:15: Discussion

15:15 – 15:45: *** Tea break ***

Data:
15:45 – 16:10: Transient astronomy and machine learning for cosmology in the era of LSST — Michelle Lochner (UCL)
16:10 – 16:35: Bahamas: Bayesian reanalysis of SNe data — Hik Shariff (Imperial)
16:35 – 17:00: Discussion
—-

On Thursday 29th January 2015 a LCDM was held with the programme below.

14:00 Katy Clough “Adaptive Mesh Numerical Relativity and Critical Phenomena in Bubble Collapse” (KCL)
14:30 Jonathan Braden “Preheating : A Shock-in-Time Connecting Inflation to the Hot Big Bang” (UCL)
15:00 Break
15:30 Alexander Khanin – “Bayesian Analysis of Cosmic Rays” (IC)
16:00 Robert Hogan – “GAz: A Genetic Algorithm for Photometric Redshift Estimation” (KCL)
16:30 Discussion
17:00 Close

On Thursday 11th December 2014 a LCDM was held with the programme below.

14:00 – 14:25: Alvina On (MSSL), “Cosmic Magnetic Fields”
14:25 – 14:50: Emma Chapman (UCL), “Foregrounds in 21cm Cosmology”
14:50 – 15:15: Discussion
15:15 – 15:45: *** Tea break ***
15:45 – 16:10: Zac Kenton (QMUL), “Inflation in String Theory”
16:10 – 16:35: Arttu Rajantie (IC), “Spacetime curvature and the Higgs stability during inflation”
16:35 – 17:00: Discussion

On Thursday 30th October 2014 a LCDM was held with each of the London cosmology groups providing an introduction to their members and research interests. The programme is below with links to talks where available.

2:00 – QMUL Overview
2:10 – MSSL Overview
2:20 – Imperial Overview
2:30 – KCL Overview
2:40 – UCL Overview
2:50 – Brainstorming
3:10 – Group Discussion/Coffee
4:00 – Final Summary leading into – Website discussion (for organisers)
/ General discussion (everyone else)

Update: some talks from the day are now available below.

The next London Cosmology Discussion Meeting (LCDM) is on the topic of numerical cosmology.

The meeting will take place in the Royal Astronomical Society (RAS) at Burlington House from 2-5pm on Thursday 13th February.

The provisional schedule is:

14:00 – 14:25: Nina Roth (UCL), “Large-scale structure with N-body simulations”

14:25 – 14:50: Marc Manera (UCL), “Mock galaxy catalogues for big surveys”

14:50 – 15:15: Discussion

15:15 – 15:45: *** Tea break ***

15:45 – 16:10: Arttu Rajantie (IC), “Simulating quantum fields”

16:10 – 16:35: David Mulryne (QMUL), “Numerically calculating inflationary correlation functions”

16:35 – 17:00: Discussion

17:00 To the pub

The LCDM on Thursday 19th September took place at the RAS and was on inflation after the Planck satellite.

The speakers, with links to their talks, were:

David Mulryne (QMUL): “Introduction to multifield Inflation”

Jonny Frazer (UCL): “Predictions in multifield inflation”

Eugene Lim (Kings): “Inflation after Planck”

John Ellis (Kings): “Planck-compatible inflationary models“

Update — there are now links to some of the talks given on the day from the program below.

The next London Cosmology Discussion Meeting (LCDM) is on the Cosmic Microwave Background.

The meeting will take place in the Royal Astronomical Society (RAS) at Burlington House from 2-5pm on Thursday 18th April.

The details:

This meeting will be more pedagogical than usual, with the aim being to give everyone – particularly the graduate students – a solid grounding in both the physics and observations of the cosmic microwave background radiation.  The program is:

‘CMB physics’
Jonathan Pritchard (Imperial)

‘Baryon acoustic oscillations’
Will Sutherland (QMUL)

‘CMB data analysis’
Stephen Feeney (UCL)

‘Exploiting sparsity for CMB data analysis’
Jason McEwen (UCL)

Each speaker has been asked to prepare about 30 minutes of material and there will be a half-hour caffeine break after Will’s presentation.

Update: The schedule below now links to some of the talks given on the day.

The next London Cosmology Discussion Meeting (LCDM) is on two topics: Inhomogeneous Cosmology and Modified Gravity.

The meeting will take place at Queen Mary, University of London, in the G.O. Jones building (physics department), room 601, from 2-5pm on Thursday 7th March. Coffee will be provided and there will be subsidised drinks in the senior common room bar in the Queens Building afterwards.

Maps of campus can be found here.

The provisional schedule is:

Inhomogeneous Cosmology and Modified Gravity LCDM

14.00-14.25 Tim Clifton (Queen Mary): An overview of the Inhomogeneous Universe
14.25-14.50 Donnacha Kirk (UCL): An overview of the Modified Gravity Landscape
14.50-15.20 Discussion
———————————
15.20-15.50 Coffee break
———————————
15.50-16.15 Malcolm Fairbairn (Kings): Testing Cosmological Models using Gamma Rays
16.15-16.40 Ali Mozaffari (Imperial): Testing Modified Gravity in the Solar System
16.40-17.00 Discussion
———————————
17.00 Drinks in senior common room bar

The next London Cosmology Discussion Meeting (LCDM) is on the topic of reionisation.

The meeting will take place in the Royal Astronomical Society (RAS) at Burlington House from 2-5pm on Thursday 24th January.

The provisional schedule is:

Reionisation LCDM

RAS, London, 2-5pm Thursday 24th January

14:00 – 14:25 Steve Warren — Introduction to Reionisation & Observational constraints on the evolving neutral fraction of hydrogen
14:25 – 14:50 Jonathan Pritchard — Introduction to 21cm & Future 21cm observations
14:50 – 15:20 Open discussion
———————————
15:20 – 16:00 Coffee break
———————————
16:00 – 16:20 Jason McEwen — Radio interferometric imaging with compressive sensing
16:20 – 16:40 Emma Chapman — EoR foreground removal and statistical detection with LOFAR
16:40 – 17:00 Open Discussion
———————————
17:00 To the pub

There has been quite a lot of press interest in the recent evidence of a Bs meson decay into muon and anti-muon at the LHCb experiment, which places additional constraints on supersymmetric extensions of the standard model. There are also indirect consequences for cosmology, since supersymmetric particles are candidates for dark matter. Reading the BBC article, however, a layperson or even a beginning graduate student might worry that supersymmetry is in serious trouble, and that this implies we need an alternative to dark matter! But don’t switch your PhD to MOND just yet, reassuring comments from our resident expert John Ellis follow:

”As I was quoted in the BBC article: “Supporters of supersymmetry, however, such as Prof John Ellis of King’s College London, said that the observation is “quite consistent with supersymmetry. In fact,” he said, “(it) was actually expected in (some) supersymmetric models. I certainly won’t lose any sleep over the result.””

For more details, see the MasterCode website, in particular our remark that “The new measurement provides a valuable new constraint on the supersymmetric parameter space, but the observation of a Standard Model-like branching fraction for the Bs→μμ decay is quite consistent with supersymmetry. In fact, a Standard Model-like branching fraction of this decay was expected in constrained supersymmetric models like the CMSSM or NUHM1 (see, e.g., the recent MasterCode results for further details). As a result, the favoured regions in the parameter space of these models do not change significantly after the inclusion of the new constraint.”