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Showing posts from March, 2018

Stephen Hawking 1942-2018

There have been some obits out by physicists. My favorite so far is Bee's. Update: Roger Penrose's Guardian Obit is don't miss, via PW. Fernando could learn some stuff about black holes from reading it. Also, Leonard Mlodinow in the NYT.

Adios Rex

Rex Tillerson was fired, probably mostly for not getting along with the Moron in Chief, but he was also, by many accounts, a terrible Secretary of State. He lacked vision, and, surprisingly for a top CEO, seemed to have no clue how to run the organization, presiding over confusion, resignations of much of the departmental expertise, and an inability to communicate to his staff. The new CIA chief will be Bush's chief torturer.

Hulla Balu

Arun is continuing on a Balu related tear, and once again the point is to contrast Hinduism (not a religion) and once again, the target seems to be a book he hasn't read. Here is a quote from a critic: As S.N. Balagangadhara notes, if you take away the Bible and you take away Jesus, there will be nothing left that would be recognizable as a religion called Christianity. Similarly, if you take away the Quran and take away Mohammad, there will be nothing left that would be recognizable as a religion called Islam. Religions stand or fall based upon these two factors. If these two factors are necessary components of religion, it obviously means that the Indian traditions are phenomena of a different kind. You cannot use different standards of determination in judging this matter. Even Buddhism does not need a Buddha, nor does Jainism need a Mahavira.I wonder. Take away the whole corpus of Indian religious literature (Vedas, Upanishads and Puranas for a start), and what remains? I …

Quantum Field Theory

Quantum Field Theory has the reputation of being one of those subjects that separates the men from the boys. The boys, of course, go on to become particle physicists, solid state theorists, and so on, while the men find less challenging careers. I'm not sure if it's still possible to get a PhD in physics without taking a QFT course but I am quite sure that it's possible to get one without understanding it. I did take, and pass, such a course once long ago, and I've since worked a hundred or two quantum field theory problems, but I can't pretend to understand it in any deep way. It's possible that others share my intellectual handicap. Maybe that's why quantum field theory texts continue to bloom like leaves in the spring. It's hard for me to believe that there are as many theoretical physicists as there are QFT texts, but I suppose that I must be mistaken. Anyway, I'm pretty sure that I own less than 100 of them, though it has been a while si…

That Old Time Religion

Arun has posted a link to a synopsis S. Balagangadhara's "The Heathen in His Blindness," a major critique of Western study of religion. This was interesting to me since I had never managed to understand his often intricate prose. My attempt to synopsize the synopsis: Hinduism as a religion was invented by Western colonialists, as was the anthropological conclusion that religion is a cultural universal, and, in particular, that the whole sociological/anthropological study of religion is hopelessly contaminated by Abrahamic prejudices. Perhaps you are eagerly awaiting my opinion on all this - or not. Anyway, I think that if you accept his definition of religion, which essentially restricts the concept to those three Middle Eastern religions and their close relatives, what he says is true. It's also obviously true that one's culture inevitably colors one's analysis of any other culture. Balu, as he is also known, has a cultural grievance and a resulting ch…

Entropy of the Universe

In which Fernando asks a question, and CIP gets confused. In some ways the initial Universe, which is hot and uniform would seem to have a high entropy. Of course we have good reason to believe that the entropy has been increasing, at least since the big bang. If we stick to classical thermodynamics, the entropy change of a system undergoing a reversible change is given by dS = Q/T, where dS is the entropy change, Q the heat transferred, and T the temperature. So for an isolated system, undergoing reversible change, the entropy can't change. You might think that our universe is an isolated system, but it isn't really. Because our Universe is expanding at an accelerating rate, stuff at the boundaries of the Universe keeps "falling off the edge", that is going beyond the observable horizon. Another kind of horizon exists around black holes, so the amount of matter in the observable U keeps shrinking. On the other hand, dark energy keeps increasing. Any smart pe…