Below you will find pages that utilize the taxonomy term “Inflation”
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Trispectrum during Inflation
After a lot of work, “Large trispectrum in two-field slow-roll inflation” was released on the arXiv yesterday as arXiv:1203.6844. In this article Joe Elliston, Laila Alabidi, David Mulryne, Reza Tavakol and I look at the generation of higher order statistics during inflation in the early universe.
In the early universe the curvature perturbations, which later are seen as temperature fluctuations in the Cosmic Microwave Background (CMB), are initially thought to be Gaussian, but can become skewed during inflation depending on the physics of their evolution.
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Two new papers on the arXiv
Last Tuesday was a bit hectic for me as I tried to coordinate the last minute changes needed to put two papers on the arXiv servers for the next day. The two articles which are now available are numbered 1111.6919 and 1111.6940:
Calculating Non-adiabatic Pressure Perturbations during Multi-field Inflation Ian Huston, Adam J. Christopherson Abstract: Isocurvature perturbations naturally occur in models of inflation consisting of more than one scalar field.
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Outreach lecture to teachers
I gave a lecture to secondary school teachers this week as part of the Goldsmith’s Company’s Science for Society Course on astrophysics.
Having heard about the Big Bang model and some of its problems from my colleague Dr David Mulryne, I was given the task of outlining how the inflationary paradigm tries to solve these problems and some of the reasons we think it is a good model of the early universe.
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Thesis now online
I passed my viva examination a few months ago, and after very helpful suggestions from my two examiners I submitted the final version of my PhD thesis to the QMUL authorities a month ago. The paperwork all went through so I have now completely finished my doctoral training. All that remains to be done is the celebratory donning of a floppy cloth cap and scarlet robes at the graduation ceremony in a few weeks.
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Cosmo09 roundup
The Cosmo09 conference took place last week in the picturesque surroundings of CERN with lots of talks, a lot of conversation and not a little French/Swiss beer. Videos of the plenary talks are now available and the slides of every talk (including the parallel sessions) are listed in the conference programme for each session. There are a few personal notes on the sessions in the FriendFeed group.
My talk was on Thursday afternoon in the inflation session.
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Cosmo09 conference
The annual Cosmo conference for all branches of cosmology is taking place next week 7th-11th September in CERN. I will be attending and giving a talk in the inflation session on Thursday afternoon.
After last week’s Science Online London 2009 conference which I attended, I have been thinking about how to get fellow cosmologists to start interacting online. I am not sure whether anyone else will use it but I have started using the hashtag #cosmo09 on twitter and have created a FriendFeed room for the conference.
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Numerical Calculation of Second Order Perturbations
My new paper, written with Karim Malik, has just been released into the wild. We show that it is possible to numerically simulate second order perturbations for a single scalar field with a canonical action. I’ve been working on this for a long time and learned a lot about the mechanics of inflation in the process. I’ve also churned out quite a lot of python code, and learned some rudimentary parallel programming.
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First talk imminent
So it turns out that I am going to give a talk at UK Cosmo next week. It’s only supposed to be 18 minutes long, which you might imagine wouldn’t be that difficult to put together, but as you can tell from the lack of posts here recently, I’ve been having some problems.
The talk is supposed to be based on our last paper (which will soon appear in JCAP by the way), but with limited time I think I will have to speed through it pretty quickly.
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First paper on the arXiv
[Shameless plug of my own work alert!]
So today I finally became a ‘proper’ scientist and saw my name on the listings of the arXiv. Our new paper, Gravitational Wave constraints on DBI inflation, makes life difficult for the usual DBI brane inflation models by specifying some pretty strong limits on their existence, depending on the size of the scalar tensor ratio. In a nutshell, if gravitational waves from the CMB are observed, these models will have a hard time surviving.