Equivalence

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Equivalence

I want to talk a little about the central idea that led Einstein to the concept of General Relativity. To get there, I want you to perform a little experiment.

Take a moment to think carefully about the forces you feel on yourself right now. If you’re sitting, you feel the chair pushing on your back, which pushes on the rest of your body. You feel the floor pushing your feet up. You might feel the muscles and tendons in your shoulder holding your arm up, or strain your neck holding your head up. 

But do you feel the force of gravity?

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Workshop Slides: Combinations fits of ATLAS and CMS data

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Workshop Slides: Combinations fits of ATLAS and CMS data

I'm at a workshop (hosted by the theorists at U Oregon in Eugene) on recent LHC anomalies, most notably the diphoton excess of which there has been so much noise of late. I was fortunate enough to be asked to give the opening talk, showing my theorist-level fits to the CMS and ATLAS diphoton data. I thought it might be nice to put the slides I used up here. Enjoy.

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Paper Explainer: Vector Boson Fusion Searches for Dark Matter at the LHC

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Paper Explainer: Vector Boson Fusion Searches for Dark Matter at the LHC

Here, I describe a recent paper I wrote with a group of experimentalists (Jim Brooke, Patrick Dunne, Bjoern Penning, and Miha Zgubic) and a Rutgers undergrad, John Tamanas. We investigated the ability of the Large Hadron Collider (LHC) to find dark matter using a particular type of event, one called “vector boson fusion,” or VBF.

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Paper Explainer: Assessing Astrophysical Uncertainties in Direct Detection with Galaxy Simulations

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Paper Explainer: Assessing Astrophysical Uncertainties in Direct Detection with Galaxy Simulations

This is a description of a recent paper of mine, with Jonathan Sloane (a graduate student in the astro group here at Rutgers), Alyson Brooks (also a professor at Rutgers), and Fabio Governato (faculty at U Washington). We took high resolution simulations of galaxies like the Milky Way, and looked at what that can tell us about how dark matter is moving near the Earth, and what that means for how direct detection experiments look for dark matter.

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Recent Paper: Narrow or Wide? The Phenomenology of 750 GeV Diphotons

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Recent Paper: Narrow or Wide? The Phenomenology of 750 GeV Diphotons

Pretty much everything I know now about the anomaly at 750 GeV.  Read this, and you'll know it too. It’s nothing too certain, but I expected that going in. 3.6σand 2.6σ is just not that much significance to start with, so any question I ask would have conflicting and uncertain results, with at best only minor preferences for any particular result. But I internalized a lot about the experimental results by forcing myself to grind through the data, and once you’ve done that much work it seemed silly not to write a paper about it.

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Diphotons at 750 GeV

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Diphotons at 750 GeV

Yesterday was the first data release of the LHC Run-II, and there has been a lot of interest in the first hints of something new. I’m skeptical, and wishing for more data. There are some suspicious tensions with previous results, but it’s certainly not clearly wrong, and its definitely the most intriguing sign of something new since the Higgs discovery. Unfortunately, we’ll have to wait at least a year to get more data to directly speak to this anomaly. It will be a difficult wait. But while we wait, read this to find out more of what we're looking at.

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Recent Paper: Constraining the Strength and CP Structure of Dark Production at the LHC: the Associated Top-Pair Channel

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Recent Paper: Constraining the Strength and CP Structure of Dark Production at the LHC: the Associated Top-Pair Channel

I'm going to describe my most recent paper, written with my now-frequent collaborator, Dorival Gonçalves, postdoc at the IPPP at Durham University. This paper is closely related to Dorival and my previous paper together, which I wrote about here. In fact, this was the project we were working on when we realized what we were doing had application to Higgs physics. When that happened, we decided to drop what we were currently working on and rush out the Higgs-related paper. Then we returned to the original idea, which was to find ways to study dark matter production at the LHC.

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Recent Paper: Dark Matter in Leptophilic Higgs Models After the LHC Run-I

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Recent Paper: Dark Matter in Leptophilic Higgs Models After the LHC Run-I

In this post, I'll talk about my recent paper, written with my graduate student, David Feld.

This paper is interested in leptophilic Higgs models, and their possible connection to dark matter. I'll explain what those are in a bit. Such models have been considered before, but looking around at the literature, we didn't see a lot that had been updated after the discovery in 2012 of the Higgs boson at 125 GeV. We wanted to see what changed once we folded these new results in to the mix.

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Recent Paper: Boosting the Direct CP Measurement of the Higgs-Top Coupling

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Recent Paper: Boosting the Direct CP Measurement of the Higgs-Top Coupling

I'm going to describe my most recent paper, written with Dorival Gonçalves, postdoc at the IPPP at Durham University. This is the arXiv version, as is usual in particle physics, we submit to the preprint serve, collect up commentary and citation requests, then get around to submitting to a journal.

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