ferdinandjproa @timely_pace@qoto.org

“19 years ago today, back when the rivalry was real…”

In an existential if bizarrely comic moment, the new movie “Oppenheimer” revives an old question about the safety of testing nuclear weapons.

Before going any further, let me check first the consistency in units by momentarily resorting to SI system of units from the Heaviside-Lorentz Planck units that I have been using. In this regard, …

Lecture notes for a 'Part III' course 'Black Holes' given in DAMTP, Cambridge. The course covers some of the developments in Black Hole physics of the 1960s and 1970s.

Classical black holes are defined by the property that things can go in, but don't come out. However, Stephen Hawking calculated that black holes actually radiate quantum mechanical particles. The two important ingredients that result in back hole evaporation are (1) the spacetime geometry, in particular the black hole horizon, and (2) the fact that the notion of a "particle" is not an invariant concept in quantum field theory. These notes contain a step-by-step presentation of Hawking's calculation. We review portions of quantum field theory in curved spacetime and basic results about static black hole geometries, so that the discussion is self-contained. Calculations are presented for quantum particle production for an accelerated observer in flat spacetime, a black hole which forms from gravitational collapse, an eternal Schwarzschild black hole, and charged black holes in asymptotically deSitter spacetimes. The presentation highlights the similarities in all these calculations. Hawking radiation from black holes also points to a profound connection between black hole dynamics and classical thermodynamics. A theory of quantum gravity must predicting and explain black hole thermodynamics. We briefly discuss these issues and point out a connection between black hole evaportaion and the positive mass theorems in general relativity.

A search is presented for the Higgs boson decay to a pair of electrons (e$^+$e$^-$) in proton-proton collisions at $\sqrt{s}$ = 13 TeV. The data set was collected with the CMS experiment at the LHC between 2016 and 2018, corresponding to an integrated luminosity of 138 fb$^{-1}$. The analysis uses event categories targeting Higgs boson production via gluon fusion and vector boson fusion. The observed upper limit on the Higgs boson branching fraction to an electron pair is 3.0$\times$10$^{-4}$ (3.0$\times$10$^{-4}$ expected) at the 95% confidence level, which is the most stringent limit on this branching fraction to date.

A more general setup is where the Higgs boson carries a full four-momentum, . Here, the Higgs boson has more than one spatial four-momentum components as it travels before decaying. We still attrib…

Our Milky Way galaxy is an awe-inspiring feature of the night sky, viewable with the naked eye as a horizon-to-horizon hazy band of stars. Now, for the first time, the IceCube Neutrino Observatory has produced an image of the Milky Way using neutrinos—tiny, ghostlike astronomical messengers. In an article to be published tomorrow, June 30, ...

“Lots of NANOGrav folks are rightly making the news but I want to highlight Prof. Sarah Vigeland, who shies away from the limelight, but is the chair of the NG gravitational-wave Detection working group. It's meticulous scientists like Sarah who make sure the analysis is right!”

Marx's analysis of the Concept of the Derived Function

“tell me Marx did not publish this pls”

The Universe should be humming.