Reality Conditions

Wednesday, October 31, 2007

Yet more Shameless Self-Promotion

Transition rate of the Unruh-DeWitt detector in curved spacetime

Jorma Louko, Alejandro Satz

Abstract: We examine the Unruh-DeWitt particle detector coupled to a scalar field in an arbitrary Hadamard state in four-dimensional curved spacetime. Using smooth switching functions to turn on and off the interaction, we obtain a regulator-free integral formula for the total excitation probability, and we show that an instantaneous transition rate can be recovered in a suitable limit. Previous results in Minkowski space are recovered as a special case. As applications, we consider an inertial detector in the Rindler vacuum and a detector at rest in a static Newtonian gravitational field. Gravitational corrections to decay rates in atomic physics laboratory experiments on the surface of the Earth are estimated to be suppressed by 42 orders of magnitude.

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Wednesday, October 24, 2007

#1 in Google meme

Yet another meme that has been going around to replace what could have been a thoughtful post with some navel-gazing fun. This time the idea is to find five search keywords or phrases that retrive your blog as first result in Google. I found several of these after some playing around (trying to avoid obvious things like post-titling phrases unlikely to appear elsewhere). My 5 favourite examples:

1. reality conditions

Yes, an obvious one, but considering that it is a common phrase in mathematics and mathematical physics and also the title of a book, I am rather proud to be the first one (the first two, actually).

2. evolution and theism compatible

I get both results #1 and #2 for this one! If that doesn't make me a Neville Chamberlain evolutionist, I don't know what can make it ;).

3. review thomas nagel

4. review lee smolin

5. review cosmic jackpot

My book reviews seem to be rather popular with Google. I am also #2 (after Amazon) for the simple string "cosmic jackpot". Curiously enough, I am #1 for "review neal" but not for "review neal stephenson".

And as bonus, the result that indulges my vainity the most: I am the #10 google result for the search "alejandro", thus appearing in the first page displayed, just a few lines below Peru president Alejandro Toledo, filmmaker Alejandro Amenabar, and Alexander the Great (who is Alejandro Magno in Spanish).


Wednesday, October 10, 2007

Book meme

This has been going around the Internets in the past weeks, and it is as good a way as any of making a post when I have nothing interesting to post about. The rules are:

1. Bold what you have read
2. Italicise what you started but couldn't finish

The second seems to be the main point –apparently this is a list of the books more often left unfinished or something like that. To make it slightly more interesting I will add a couple of comments here and there, on all the unfinished books and some of the others.

Jonathan Strange & Mr Norrell
Anna Karenina
Crime and Punishment
One Hundred Years of Solitude
Wuthering Heights
The Silmarillion
Life of Pi: a novel
The Name of the Rose
Don Quixote

Well, almost –perhaps I should have italicized. When I had to read it for high school I did finish it, but cheated and skipped some of the chapters which are unrelated sub-stories told by characters within the novel. I have the firm intention of rereading it without cheating some day.

Moby Dick

This was the second novel I read in my life –the first being Robinson Crusoe- or so I thought for most of my childhood. Later I discovered that the version I had read was a heavily abridged edition, perhaps a fourth of the length of the original novel. (Robinson I had read unabridged, honestly!) I only caught up with the whole book some four or five years ago. Great stuff.

Madame Bovary

This one is high on my list of Great Books that Suck –okey, I exaggerate, but it had little or nothing that appealed to me. I like Stendhal much better than Flaubert.

The Odyssey

Tried it right after finishing The Iliad with no problems, but got distracted with other stuff and never picked it up again. Needless to say I fully intend to read it some day.

Pride and Prejudice
Jane Eyre
A Tale of Two Cities
The Brothers Karamazov
Guns, Germs, and Steel: the Fates of Human Societies
War and Peace
Vanity Fair
The Time Traveler's Wife
The Iliad

The Blind Assassin
The Kite Runner
Mrs. Dalloway
Great Expectations
American Gods
A Heartbreaking Work of Staggering Genius
Atlas Shrugged
Reading Lolita in Tehran: a memoir in books
Memoirs of a Geisha

See my review of the whole Baroque Cycle. I fully understand why this one is on the list; it took me about half a year to go through it. The other two volumes are quite more difficult to put down.

Wicked : the life and times of the wicked witch of the West
The Canterbury Tales
The Historian: a novel

I’m starting to read this one just now! Looks promising, so it will soon become a bolded item.

A Portrait of the Artist as a Young Man
Love in the Time of Cholera
Brave New World
The Fountainhead
Foucault's Pendulum

This one and The Name on the Rose were very high on my list of Favourite Books Ever for several years (roughly the second half of my teens). I can’t understand what happened to Eco after this; The Island of the Day Before and Baudolino were miles below the previous novels in quality. I have not read The Mysterious Flame of Queen Loana, but my hopes are not high.

The Count of Monte Cristo

Read it in a children’s edition which must have been about one twentieth of the size of the original book… so no, I don’t even count it as unfinished. Definitely want to read it some day.

A Clockwork Orange
Anansi Boys
The Once and Future King
The Grapes of Wrath
The Poisonwood Bible: a novel
Angels & Demons
The Inferno
The Satanic Verses
Sense and Sensibility
The Picture of Dorian Gray
Mansfield Park
One Flew over the Cuckoo's Nest
To the Lighthouse
Tess of the D'Urbervilles
Oliver Twist
Gulliver's Travels
Les Misérables

Yes, I read the complete edition of this one, including the description of the battle of Waterloo, the philosophy of convents and the disquisition on criminal jargons. And loved it, by the way.

The Corrections
The Amazing Adventures of Kavalier and Clay

Read this one on recommendation by my cynical friend, which reminds me that it's been a while since the last time we had one of our little blogfights -maybe he will come and make some sarcastic comments on my readings to enliven things a bit

The Curious Incident of the Dog in the Night-time

??? How can many people leave this book unfinished? It must be the easiest to read great novel ever written. Maybe they were put off by discussions of prime numbers and the Monty Hall problem?

The Prince

I assume it is Machiavelli. It was long ago that I tried, and I’m not sure why I didn’t finish it. Probably I just didn’t find it interesting.

The Sound and the Fury
Angela's Ashes: a memoir
The God of Small Things
A People's History of the United States: 1492-present

Yes, I got this one and read it in the last months, after finishing The Baroque Cycle. It is better crafted as a novel and mostly more exciting to read, but the ending is more disappointing and it didn’t have as many little fascinating things as TBC. Also, I am somewhat less interested in twentieth-century geekery than in seventeenth-century geekery. Leibniz beats Turing all the way.

A Confederacy of Dunces
A Short History of Nearly Everything
The Unbearable Lightness of Being
The Scarlet Letter
Eats, Shoots & Leaves
The Mists of Avalon
Oryx and Crake : a novel
Collapse: How Societies Choose to Fail or Succeed
Cloud Atlas
The Confusion

Notice that the first two parts of The Baroque Cycle are on the list, but not the third. Anyone who has invested the time of going through the first two will not leave the last one unfinished and make the whole previous effort pointless.

Northanger Abbey
The Catcher in the Rye
On the Road
The Hunchback of Notre Dame
Freakonomics: a Rogue Economist Explores the Hidden Side of Everything

I read most of this one standing at the WH Smith shop of the Heathrow bus terminal, once that I got stuck waiting there a couple of hours for a bus and had finished off my reading material on the plane.

Zen and the Art of Motorcycle Maintenance : an Inquiry into Values
The Aeneid

Made a half-hearted attempt as a teenager. Didn’t get too far.

Watership Down
Gravity's Rainbow
The Hobbit

I'm not surprised about The Silmarillion, but it's perplexing that The Hobbit is on the list and Lord of the Rings is not. I know many people who tried it and left it at the prologue or shortly after.

In Cold Blood : A True Account of a Multiple Murder and Its Consequences
White Teeth
Treasure Island

Another surprise. How can you pick up this book and (assuming you like pirate stories, and if not why would you pick it up?) not read it complete? What’s wrong with you?

David Copperfield
The Three Musketeers

See here for some intensely personal comments on Dumas.

Overall: 32 read and 5 unfinished, out of 106 in total. Or if you insist on counting the Quixote as unfinished, then I count The Historian as finished to balance –I am reading it now and liking it, so it is just a matter of days till it can be added to the list. How did you do?

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Saturday, October 06, 2007

Spinny Foamy talk

Last Tuesday, Johnathan Engle gave a talk for the International Loop Quantum Gravity Seminar. The talk was on the new spin foam models that have been proposed this year; namley, this one by Engle, Pereira and Rovelli and this one by Freidel and Krasnov. We have been having some discussions on both papers here at the Nottingham group as well. The two things that seem to me more important are the possibility of getting a better understanding of the role of the Immirizi parameter, which for first time is appearing in spin foam models, and the possibility of checking which is the correct dynamics via semiclassical calculations.

The audio and the slides of Engle's talk are available at the above link. If you are interested in getting an idea of the current state of research in the LQG/spin foam community, I encourage you to listen to the full audio. About the last half of it is an hour-long discussion between (mostly) Rovelli and Freidel. For me it gave me a strong feeling of how little really is known, and how basic are the disagreements that are still possible between people follwing essentially the same research program. It is something what does not see so directly in papers or even in most conference talks.