How big is an electron?
/So I got a question about whether the fact that an electron is part of a quantum field means that the charge of an electron is “spread out” somehow
Read MoreSo I got a question about whether the fact that an electron is part of a quantum field means that the charge of an electron is “spread out” somehow
Read MoreI 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?
Read MoreI'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.
Read MoreHere, 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.
Read MoreThe first part of this is a non-specialist description of the results of Moriond concerning the diphoton anomaly. About halfway through it will transition into a more technical discussion, including new plots I've made giving my theorist-level combinations of the data shown.
Read MoreWe looked for dark matter in the Magellanic Clouds. We didn't find it, but we learned a lot, and the search continues.
Read MoreSo we found gravitational waves today. Who, what, when, where, why and how?
Read MoreThis 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.
Read MorePretty 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.
Read MoreYesterday 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.
Read MoreI'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.
Read MoreI keep my eye on the results of a lot of experiments. But there is one type of experiment that is my favorite. Not because necessarily because it yields the strongest bounds, or has the most interesting possible signals or anything, but because the physics behind it is so much fun.
Read MoreThis week (October 6, 2015), the Nobel Committee announced that Takaaki Kajita and Arthur B. McDonald were awarded this years Nobel Prize in Physics for
"the discovery of neutrino oscillations, which shows that neutrinos have mass"
So what are neutrinos, and why is their oscillation so interesting and Nobel-worthy?
Read MoreIn 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.
Read MoreI'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.
Read MoreBut what dark matter? Unfortunately, I don't know. No one knows. But let's go through some of the possibilities anyway.
Read More"Why is the sky blue?" is one of those canonical little kid questions that is shorthand for "inquisitive tiny human confounding their adults."
Read More...physicists discovered that the uranium atom was really large; at least as far as incredibly microscopic objects go. Everything they threw at it seemed to "hit," so the nucleus was "as big as a barn."
Read MoreI decided to put together some useful facts about the dark matter halo in which we live. Useful of course is a relative term.
Read MoreWhy does a mirror switch left and right, but not up and down?
Read MoreQuestions? Comments? Ask me on twitter @physicsmatt
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