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Other interesting things in ArXiv (11 Jun 2009)
Basically, there were so many interesting and useful papers (or at least they were useful for me) – lecture notes, reviews – that it will give me hard time posting reviews of all of them here – since I am lazy, I’ll just try to list some of them. Umut Gursoy et al. “Thermal Transport [...]
Tour of Ares IX
Jim Halsell (former astronaut) takes Miles O’Brien on a tour through the various components of the new NASA Ares IX rocket.
Into dark ages or again about GRB090423
Back in April, I already wrote about GRB090423 – currently the most distant detected object in the Universe. Yesterday, two papers with details of mesurement have appeared in astro-ph (unfortunately, Icannot give you the links – see my comment below). Let me remind you that currently the redshift of the most distant galaxy we observed [...]
How to spot a black hole on the Sky
Here is a video from NewScientist featuring simulations by Loeb and his collaborators (we have discussed Loeb’s results several times on NEQNET). The idea is that BH acts as a strong gravitational lense, so if we have a close system “star-BH”, we will see a very specific pattern of light when the companion star crosses [...]
This and that in ArXiv on Monday
Due to unbelievable overload of the last days let me simply list the recent papers in ArXiv that I found the most interesting: 1. Quantum information T. Tilma el al., “Is entanglement a critical resource for quantum metrology?” Can we beat the shot-noise limit (and get to the Heisenberg limit) in quantum metrology by playing [...]
Three last Susskind’s lectures on general relativity
… that is, lectures 10, 11 and 12: gravity in 4+1 dimensions, dynamics of scalars in curved spacetimes (and behavior of gravitational potential – which is scalar), a bit of topology (Euler characteristics), Lagrangian of a relativistic massive point particle, geodesics in curved spacetime and, finally, Schwarzschild solution.
Biocentrism: book review
I was asked to review the book by Dr. Robert Lanza called “Biocentrism: how life and consciousness are the keys to understand true nature of the Universe“. If you are a scientist good enough in your area of expertise, at some point you start wondering whether you can explain everything around you, every single event, [...]
An exoplanet near ultracool star
New record in astrometry and exoplanetology – the authors of 0906.0544 are talking about discovery of the planet in the vicinity of a very light star. The mass of the star is about 0.07 Solar masses, i.e., equivalent to 3-9 Jupiter masses – it is actually near the lower mass limit for an object to [...]
Workshop on tests of gravity in Case Western – day 2: aether and modified gravity
Let me finally briefly review the reminder of the second day of the workshop. Justin Khoury (whom I knew from Perimeter years and who is in Penn now) gave the first talk afternoon – titled “observational hints of IR modified gravity”. His talk followed Nima’s, and the latter almost completely blew me away, so I [...]
Susskind’s general relativity – lecture 9
… where Leonard Susskind discusses spacetime – spacelike, timelike and lightlike directions, explains how one gets special relativity from general relativity (post-Newtonian approximation), non-relativistic limit of GR and finally … Einstein equations (hurray!)
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On moduli stabilisation in heterotic orbifolds
April 24, 2012 09:04 -
A holographic model of the quantum Hall effect
April 19, 2012 09:04 -
Transdimensional Multiverse Measures
April 18, 2012 11:04 -
Large non-Gaussianity from axion inflation
January 31, 2012 14:01 -
On strong disorder renormalization
March 18, 2011 20:03
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Momchil: I want to ask the experts about an apparent confusion, that appears in many papers on the Unruh effect. As you stat...
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Paul: Excellent list! how lucky you are to be involved in the effort to solve some of these. On time, I question its re...
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philbert: Simple illustration and may apply to mixed layer boundary layers, how about the stable and other types of boundary ...
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Micro: Can 2 question provide a common solution? Black holes, information loss paradox and Ultra high energy cosmic rays. ...
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James Ph. Kotsybar: SAGITTARIUS A* -- James Ph. Kotsybar Mysteriously cloaked, obscure despite Interior illuminating glare, Long ...
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cad: The presentation can be found in several formats at http://pirsa.org/08110051/...
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Leo: Ok I have a question: if a black hole is supermassive, say 100 billion solar mass, let's suppose Alice fells int...
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superkuh: I am glad you are back! No more disapointing weekly refreshings of that monkey....
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