Last weekend movies (5th week 2012)

Compared to last weekend, this one was a bad movie weekend. I also grew a little bit bored of doing nothing and decided to get some work done. Nevertheless, I'm trying to keep with my vacation goal: to watch and read as much media as possible...

1. Moneyball, ****
   Based on the story of Billy Beane, one of the first baseball managers to put together a team based on computer analyzed statistics who is still trying to win a championship. I never know how to classify biographic films, I guess this is a drama. It has a good pace and flows. I actually enjoyed it.
   
   
2. Immortals, ***
   King Hyperion marches against the Greek gods and it's up to Theseus to stop him before he frees the Titans. I really liked this film, the visual design is impressive—say, e.g., the young golden gods and the golden but dirtied demi-god Theseus—and the landscape composition is impressive. The retold of Theseus and the Minotaur is amazing!
   
   
3. Colombiana, ***
   A drug lord's family is murdered and only his little girl survives. She grows up to be a perfect assassin looking for revenge. The film was scripted by my favorite femme-fatale enthusiast Luc Besson—Mathilda, Nikita, Leeloo—. It's a good action film with a lot of parkour.
   
   
4. Johnny English Reborn, ***
   Johnny English left the British secret service in disgrace but happenstances bring him back and gets a chance to clean his name. Mr. Atkinson comedy is good, specially his faces. It's a no brainer, I just sat down and laughed for half the movie.
   
   
5. 11-11-11, **
   A writer losses his family and stats realizing that bad things happen to his family on November 11th, but the worst is yet to happen. In the beginning I started to get bored with this horror film, but then came the ending and I really loved it. I have always loved non-hollywood endings.
   
   
6. Killer Elite, **
   A retired assassin is blackmailed and brought back to kill a team of ex-SAS soldiers involved in the assassination of a Sheikh's family in Oman. A passable action film, not so much action, not so much of a story, one of the stars is just out of respect to Al Pacino.
   
   
7. Salvation Boulevard, **
   A not-so-sure born-again-christian is witness to an accidental shooting committed by his mega-church preacher who decides to keep everything under the table. It's a great farcical film on the subject of false and self-justified "faith."  

Really, what is happening with television series? ...

1. Last Man Standing, (no episode?)
   
   
   
2. Castle S04-E13, ****
   A dog judge and trainer gets killed and it is up to Castle and Beckett to find out the reason why.
   
   
3. Hawaii Five O S02-E14, ****
   The mystery of the past is unfolding as a robbery entangles with the past.
   
   
4. Big Bang Theory S05-E14, ****
   
   It's back to the beginning with Leonard dating penny and everybody else being their old selves from the first season.
   
   
5. Psych, (not yet back?)
   
   
   
   
6. Wilfred S01-E01,  ***
   
   An US remake of the Oz series, a suicidal man finds a "friend" in the bastardy dog of his hot neighbor.
   
   
7. Once upon a time S01-E01-07,
   
   The land of fairy tales suffered a horrible fate, the Evil Queen curse them to a place of horrors: our world. Now, it is upon Snow White's daughter and grandson to fix things in Storybrooke, Maine, and end the curse.

It seems like we are getting a curse too, because Lyx and I haven't found time to sit down and watch those old  films with Audrey Hepburn. I really hope we can do something about it next weekend. 

LWP: Quantum memory with a single two-level atom in a half cavity

by Y. Wang, J. Minar, G. Hetet, and V. Scarani.
Physical Review A 85, 013823 (2012)

Wang and collaborators show that it is possible to store a single-photon pulse in a two-level atom within a half cavity setup where the decay rate between the atom and the light is controlled by motion of the one mirror in the half cavity.

A dipole-field interaction leading to optical Bloch equations from Heisenberg picture is used; the effects of the half-cavity are encoded in a term accounting for decay  into the half-cavity (pulse) mode, decay and noise introduced by the environment are also taken into account. Assumptions include: Markov approximation (long half-life times compared to light's round-trip between atom and mirror), small mirror motion (of the order of a wavelength) leading to neglect amplitude changes in time scales smaller or equal to a round-trip time—but this cannot be assumed in the phases due to the importance of interferences in the sysme— 

The probability of the two-level system absorbing a single-photon wave packet is found and a suitable decay function is given that maximizes such probability. Storage is achieved by placing the atom at a node of the half-cavity system. Then, the emission efficiency is calculated and a decay rate is defined which controls the temporal shape of the outgoing single-photon pulse. The authors present simulations for a sampling of time-bin single-photon pulses and their respective control decay-rate leading to high fidelity storage and possible implementations of their protocol.

The article is didactic in its presentation and the topic is quite interesting. I was not familiar with half-cavity schemes and this manuscript presents a nice survey of references in the topic. I hope experiments using their protocol follow soon.

The Black Swan by Nassim Nicholas Taleb

The Black Swan written by Nassim Nicholas Taleb deals with the impact of the highly improbable—the actual subtitle of the book—in the real world. The title comes from the fact that one single event is enough to prove a theory wrong; in this case the European theory that all swans were white previous to the discovery of Australia and black swans.

I really hated/loved the book. The mean reason for the first was the introduction of an example in the person of a writer—which I couldn't find in Google—that made me believe that Dr. Taleb was some kind of literary conman creating a fake narrative to advance his ideas. I felt betrayed. I like confidence games but I don't like being conned by an author while dealing with a serious topic. Good thing is that later, in a footnote, it is made clear that the author/example was mere fiction, a gedankenexperiment. Then, I came to love the book: It is an anecdotal narrative denouncing our weakness and inclination for anecdotal, causal narratives that blinds us from the skeptical, empirical analysis of events in economics, history, sociology and other human endeavors to understand our  non-ideal selves, societies and surroundings. I think I can construct another paradoxical phrase like the latter: In parts, t is a name dropping exposition denouncing name dropping expositions. 

I found many things to like from the manuscript—a flowing prose filled with real and imaginary examples, an ample reference and bibliographical section (almost one third of the electronic version)—and just one to dislike: I felt the first two parts became repetitive.

The ideas are sound, our actual knowledge does not allow us to simulate realistic scenarios to provide accurate predictions and, most probably, you and I will be long dead when, if, such an exercise becomes feasible—think about Assimov's psychohistory in Foundation *wink*.

Is there a way to predict the future when it comes to phenomena that belong to the so-called Extremistan (most of the modern real world)? No.

Then, what's the use of knowing that? Awareness, there are infinitely many things we don't know that could affect us, but one we can try to control: our actions and, thus, our exposure to those unknown.

It's a great book, try it. I even see it as a kind of philosophy of life. I am really thankful to my brother Andre for suggesting it to me. I think that I would not have picked it up by myself.

I, the media consumer...

The life and times of a starving vagabond is many things and nothing at all. It is an attempt to practice English, which allegedly is my second language. Sometimes it is a conduct to free my shoulders through cathartic ranting or disjointed—but therapeutic—narrative. Most of the time, it is just about post-consumption impressions.

While the starving part of the blog's title comes from a story of two close-friends (cousin Shaggy and I) driving through Mexico without much money and eating boiled potatoes and eggs, cheese and hard bread for one week, it also reflects my urge for consumerism and consumption of narratives in any given media format. I hunger for stories presenting diverse points of view that may—or, most probably, not due to my intrinsic stupidity—widen my perspective on the condition of being human.

Being human is so amazing, so different: there's almost 7 billion different ways of being human in the present; plus some three or four billion death ways of being human since the beginning of homo sapiens. Can a single individual experience the whole spectra of humanity? My answer is no, being human is a conjunction of the person, his/her ideas and actions, people interacting with him/her (with their ideas and actions), surroundings and the succession of random events that, all together, I come to call life.

In recent years, I have become a consumer of other people's points of view and have got it with mine. Curiously, I have started to find more and more taxing—and kind of useless—to be in social gatherings where there are so many people that makes it impossible to have a true dialogue leading to the exchange of opinions. I find myself leaving parties with small pieces of information from this or that person and end up reconstructing a story that has my point of view inherently embedded. I want to learn what you think about love, honesty, ethics, vengeance, religion, death and whatnot. I don't want to reconstruct your ideas through dilute and disjoint one minute burst of conversation and end up creating what I think is your narrative from my point of view. I rather read, listen or watch them whole in media. Thus, my consumerism—my desire to gather and collect enormous quantities of information—is born.

Trying to turn my consumption of media for the better, I use it to practice my English and synthesis skill. I'm not trained in aesthetics nor semantics, thus my reports on the consumed works are nothing but online dumps of impressions left on me by them—and a sorry excuse to use English in a non-scientific context—. Anyway, I hope the Last Weekend Movies or Last Month Book series of posts help you choosing a film, tv-series or book to kill time with.

Last weekend movies (4th week 2012)...

This was a nice long weekend that I'm sure is gonna remain unchallenged in my personal annals of laziness for years to come. It also was a weekend of independent cinema...

1. Fright Night, ****
   It has been ages without a vampire movie! This is a reboot of a 80's film with the same name. A vampire comes to town and its teenage neighbor has to fight it to protect his loved ones. One star is pure euphoria for finding a horror movie that involves mythological creatures and not a human serial killer.
   
   
2. Beginners, ****
   A man's life after the death of his father trying to construct a relationship— fighting his impulses to always run away—while dealing with the past; his father came out the day his mother died and his take on the family makes him evade relationships. This is a great and dramatic romantic comedy. The characters are so fresh and lovable. And the pace is just perfect to get soaked with the photography and the music.
   
   
3. Our Idiot Brother, ****
   Ned is a naive, honest, kind and idealist man who always tries to empathize with the neighbor (I like the Spanish word "prójimo" more but there exist no English equivalent) but manages to always screw things up, or so it seems like. The topic, honesty and idealism, really got me. It is a fresh and elegant comedy of situations with a big human factor on it. 
   
   
4. Lucky, ***
   A newbie serial killer inherits a winning lottery ticket from one of his victims and his newly won money gets the attention of his childhood love. They get married and manage not to kill each other for a few weeks. It has been ages since I watched a dark comedy and this one really got me smiling, it lacks a great script but it is morbid and funny enough.
   
   
5. Texas killing fields, ***
   There's a serial killer on the loose in rural Texas and two cops get emotionally involved in the case. This crime drama is loosely based on a real case. The story is so dark that the film doesn't manage to show it most of the time, nevertheless the photography is good and the takes of the Texas bayou managed to give me the chills.
   
   
6. The Art of Getting by,  ***
   A lonely teen has to find himself or flunk high-school. I liked the opening: "you are born alone, you will die alone" which is a chopped paraphrase of Orson Welles'  "We are born alone, we live alone, we die alone. Only through our love and friendship we can  create the illusion for the moment that we are not alone." The rest of the movie can be considered an audio-visual rendition of the rest of Mr. Welles' phrase.
   
   
7. The Son of No One, *
   A young cop is haunted and hunted by ghosts of his past when he killed two men. The crimes of past and present intertwine in this not so much of a thriller with the background of 9-11. It's a good idea but I guess you need to have some context that I lack to really appreciate the movie.
   
   
8. Lone Wolf and Cub 6, *
   This film should have a three or four stars rating but I watched the first five parts in the last two weekends and the memory of them are too fresh in my mind. The lone wolf finally faces his rival the Ura-Yagyu and nothing happens. C'mon! Give me an ending! I read somewhere that they are planning a new movie for the series with possible release date in 2014.

What is happening with the television series, I have never followed a season in the past and it is very annoying that during this month some of them have been going in and out...

1. Last Man Standing S01-E14, ****
   Mike screws it big time with the neighbors thanks to his honesty, leading to troubles with his socially active wife. In the end, well, Mike's proven right.
   
   
2. Castle S04-E12, ****
   The shadows behind power reappear to keep the mayor of New York from running for governor and keep Beckett out of her mothers case.
   
   
3. Hawaii Five O, (no episode?)
   
   
   
4. Big Bang Theory, (no episode?)
   
   
   
   
5. Psych, (not yet back?)
   
   
   
   
6. Phineas and Ferb S01-E01-46,  *****
   
   This is a simple, ten minute long cartoon, about two creative and industrious kids trying to spend summer at their best and their teenage sister trying to bust their plans. It's so innocent and creative and full of stories in just 10 minutes. I really liked it, it just made me laugh again and again.
   
   
7. Game of Thrones S01-E01-10, (mini-series)  ****
   
   Winter is coming! A land where winter brings shadows and horrors is involved in incestuous political intrigue and in the verge of an all out war. Stage and wardrobe design are awesome, the characters have personality and deepness. I only didn't like the slow pace at the beginning but then the epic scale of the plot may need such a pace to develop.
   
   
8. Falling Skies S01-E01-10, (mini-series) ****
   
   An alien vanguard has taken over the earth and a ten percent of the original population survives. Some of these survivors have organized in a resistance trying to figure a way to bring the fight back to the aliens. Great effects, great alien designs, good episode progression, crappy season finale.
   
   
9. The Borgias S01-E01-09,  (mini-series)  **
   
   Rodrigo Borgia has been elected pope Alexander VI and the Borgia family reaches the apex of their political station which is gonna last just a few decades. A free take on the historical Borgia family and its influence in the geopolitics of the Papal States and Mediterranean Europe during the Renaissance. Jeremy Irons plays the role of Rodrigo Borgia! Awesome wardrobe and locations. I was not so happy with the episode design, it didn't manage to get me interested long enough but good to remember the old history lessons from high-school.
   
   

Sadly, we didn't have any Audrey Hepburn due to the fact that my cousin got married and Lyx went to the wedding but we are already planning next weekend. 

LWP:Absence of vacuum induced Berry phases without the rotating wave approximation in cavity QED

by Jonas Larson
Physics Review Letters 108, 033601 (2012)

Some ten years ago, Berry phase was studied in the Jaynes-Cummings model. In this paper, Larson focuses on proving that such a geometric phase arises from the use of the rotating wave approximation.

First, Larson reviews the results fro the Jaynes-Cummings model, that is, under the rotating wave approximation, and derives the accumulated Berry phases by exact diagonalization of the Hamiltonian. Then, he presents a semiclassical approximation derivation by using canonical operators for the field and Born-Oppenheimer approximation to obtain a pair of adiabatic potentials that lead to semiclassical conical energy surfaces giving a Berry phase which is identical to that given by the exact calculation for large photon number. 

Once the validity of this semiclassical approximation is provided by this example, Larson uses the same method to find the semiclassical energy surfaces for the case without the rotating wave approximation, that is, Rabi Hamiltonian, and shows that these surfaces lack the conical intersection that gives a non zero Berry phase. Actually, the semiclassical energy surfaces for this case intersect along the line given by x=0 instead of just a point. It is noted that the author carried a numerical diagonalization of the Hamiltonian and the results were confirmed.

Furthermore, Larson revisits a lambda-atom configuration where a Raman coupling scheme is used and shows that by assuming far detuned driving fields such that adiabatic elimination can be carried on, without any rotating wave approximation, the semiclassical energy surfaces for the system do not intersect at a single point and Berry phase must be zero all the time.

He also discusses the case of a single atom in a bichromatic cavity and shows that within the used semiclassical formalism there are no vacuum induced Berry phases. A trio of other systems are presented with the same result: no Berry phase when the rotating wave approximation is not used.    

It concludes, that the presence of a Berry phase in the Rabi model and other models discussed (adiabatic elimination, bichromatic cavities, etc) in the paper is a result of introducing the rotating wave approximation and not inherent to the models. Thus, a flag is raised: whenever Berry phase is the subject of study one has to be mindful of the approximations used independently of the coupling regime at hand. It may be even possible that this result may change if a multi-level approximation is taken instead of the typical two-level restriction of the Rabi model. It also points the interest of studying vacuum induced Berry phase in nonadiabatic processes. 

This is a very nice paper to read, it presents a concrete, straight to the fact introduction of geometrical phases in cavity-QED and the results are presented in a clear manner. If you are a fan of the Jaynes-Cummings model, you cannot leave this article unread.

Vacations... what do to with them?

I never know what to do with my vacations. I usually never take them and I usually get bored after a few days or even hours whenever I have to take them without having something in mind

Waking up late... check

Cleaning the house... check

Watching a movie while having breakfast... check

Chat with Lyx... check

Get bored and checking the arXiv, physics and optics journals for new papers... check

So, you see. I can even bet that before the day is gone I will be doing a little bit of algebra here and there now that I found something that caught my eye in today's listings at the arXiv.

Days off, those I can handle. It is easier to think of 18 waking hours to do whatever you want: sit at home to read a book, go downtown to take some photos, go to the cinema, all of the above. Vacations, well, vacations for me used to mean getting a one-month train pass and hop from city to city coach surfing at my friends' places for three or four days at a time; getting into the car alone or with family/friends and drive for a whole full month to hidden places; or grabbing the backpack, meet my friends at some interesting and wide area with hitchhiking and backpacking potential and spend a full month moving around the place trying to get to know it. Now, that requires a little bit of planning but not really that much, in the end you just have to figure the general area that you want to visit and that's all.

Today is the first day of my 28 day vacation. I'm supposed to be off the office until February 29th. and I have no clue what to do with it. I'm just taking the days because I cannot cash them in before my contract ends the 3rd of March. I have just one vague idea of what I want to do: Angkor Wat but that's it. I wish Lyx, Andre or Martin where here to just go over a place and start moving around until there's no Wat  left un-sighted or pagoda un-visited from Vietnam to Singapore—uhm, maybe that's way too much—.

Anyway, I'm too lackadaisical to get the visas to Vietnam and Cambodia. Most probably I will start doing my typical working day routine to overcome this ennui.

If you are looking for information about what countries require a visa for Mexicans, I found in the intertubes was this page that is photographically organized and this page that is alphabetically organized.

If you know about some beautiful place (not a beach!) in South Pacific Asia that doesn't require Mexicans a visa to travel there, please post it in the comments, I will be thankful.

Last weekend movies...

Lyx and I both got a very busy week, but we still have the Audrey Hepburn bug...

1. My Fair Lady, ****
   Based on the theater play, it tells the story of Eliza Doolittle a young street girl with a drive who search and becomes the experiment of Prof. Higgins, a brilliant scholar of language, who believes that in early XX century London language defines status. It would have been five stars if Hepburn had sang her parts and if they had done with the kill-time-while-the-scenery-is-changed songs.
   
   
2. Life as we know it, ***
   Sophie is a baby who lost her parents in a car accident and is left at the care of her mother's best friend and her father's best friend, who are a pair of self-centered modern adults used to have the life they wanted. It's a fresh romantic comedy with this modern twist on the idea of love in the times of ego.

More and more series are coming back...

1. Last Man Standing S01-E13, ****
   Mike is an angry man but any man has a hearth and now the girls manage to have a puppy for a few days and Ed... well, Ed manages to make him angrier by almost re-branding outdoor man to compensate for time-lost with his daughter.
   
   
2. Hawaii Five O S02-E12-13, **
   I just skipped episode 12 last week! The guys solve a triple murder and Chin gets married. The special forces are back in action and McGarret has to deal with the fine line between friend/enemy again, but this time it is even closer to his heart.
   
   
3. Big Bang Theory S04-E12, ****
   
   Sheldon finds out that buying forgive-me trinkets is just his strategy for a happy relationship as Amy, brilliant as she is, is still a girl and not Sheldon. The rest of the guys deal with manhood in the old fashioned way (Howard), loneliness (Leonard) and some strange gayness (Raj).
   
   
4. Revenge S01-E01-13, ***
   
   Amanda Clark's father is framed for a crime he didn't commit and dies in shame while in prison, she comes back to the Hamptons as Emily Thorne, loaded with money and ready to revenge on all those who helped framing her dad. The first five episodes are nice and fast-paced but the rest become a little bit too slow and cliche. Oh, yes, the under-laying idea is Monte Cristo. Lyx calls it "a drama" but it has all my qualifiers for soap-opera: i) String music during dramatic pauses, ii) Guys with more stylized eyebrows than girls, iii) Someone falling into a coma, iv) That someone coming out from the coma with amnesia

And yes, we still have more Audrey Hepburn to come thanks to Lyx despite the fact that she doesn't seem to like me pointing out how beautiful, gorgeous and astounding Audrey Hepburn was. 

LWP: Polariton Mott insulator with trapped ions or circuit QED

by M. Hohenadler, M. Aichhorn, L. Pollet and S. Schmidt
Physical Review A 85, 013810 (2012)

The authors address an extended Jaynes-Cummings-Hubbard model where photons in 1D or 2D arrays of coupled resonators—each of them holding a two-level system—can hop beyond nearest neighbors. This particular model is of relevance in circuit-QED—where 1D and 2D arrays of qubit+stripline resonators can capacitively couple—and in trapped ions&mdahs;where dipole interactions are long range—. So, the model are basically 1D or 2D arrays of polaritons—qubit+fied excitation—with short and long range coupling.

They study a 1D frustrated long-range hopping model in the context of trapped ions and the same in 2D by assuming a circuit-QED model. The first is studied using a variational cluster approach and a quantum Monte Carlo method (ALPS 1.3 implementation), the second only the quantum Monte Carlo method. Analytically, Metzner's local cumulants are used to calculate a photonic Matsubara Green's function for the system within a random phase approximation.

The authors find a Mott-superfluid transition by changing the hopping to qubit-field coupling ratio as usual with these models. Their results show that the Mott lobes characteristic for this transition are enlarged/reduced in the case of trapped ions/circuit-QED but they realize that neither the quantum Monte Carlo, nor the variational cluster approaches provide any evidence of a change of the universality class of phase transition in the presence of long-range hopping.

This is one of those papers that would take long to duplicate but are nice to read and learn the physics of the studied system and even more interesting if you like anything Jaynes-Cummings.

Last weekend movies...

Lyx got the Audrey Hepburn bug and I cannot be happier, she's the most beautiful actress ever, if you ask me...

1. Roman Holiday, *****
   A young princess is burn out by her public relations schedule and, under the influence of a happy drug administered to relax her, decides to escape the embassy of her country and have a free day in Rome. She meets an American journalist by chance that saves her from sleeping in the streets and takes her on a one day tour—not without selfishness. I love old movies, they are so innocent and their endings are so good.
   
   
2. Zatoichi, ****
   Zatoichi appears to be just a blind, wandering masseuse and professional gambler; but the old man is also a wrestler and proficient swordsman. In this story, his road interlaces with that of a pair of siblings that seek revenge on those who murdered their family ten years ago. Good for them, Zatoichi has some unfinished business with the murdering gang. I loved the almost static and the bizarre scenes appearing now and then, and the random act of foolishness that puts a comic touch to everything.
   
   
3. Lone Wolf and Cub 2-5, ***
   Ogami (similar to Okami, wolf in Japanese)  Ito and Daigoro keep walking the road to hell but the Ura-Yagyu is now trying to destroy the lone wolf more actively. I was expecting more after watching the first, but it gets more and more fantastic as the saga keeps going.
   
   
4. The Help, ***
   A young writer, from small town Jackson, tries her hand at narrating the lives of those negro maids from the deep south of the 60s.  It is a well done movie with good acting but I can hardly believe the story. The story would have been great if it were not just a fairy tale. The civil rights movement in the 60s was not a rosy, peaceful endeavor and I would think that even in the 60s a lot of abuse to african-american and american women happened in the deep south.

Some of the series are back from the December pause...

1. Last Man Standing S01-E12, ****
   Mike has to deal with what seems to be a punk celebrity but happens to be a man looking for a center. Of course, he almost screws things up almost making the young  pro-bass-fisher quit fishing. Tony Hawk appears for a few minutes!
   
   
2. Hawaii Five O S02-E13, **
   The special forces are back in action and McGarret has to deal with the fine line between friend/enemy again, but this time it is even closer to his heart.
   
   
3. The Cape E01-13 (Miniseries), ****
   
   A honest cop named Vince gets framed as super-villain Chess and taken for dead, but he survives and, under the tutelage of Max Malini and his Carnival of Crime train him to be the super-hero The Cape. I really liked the idea—and Summer Glau as omniscient Orwell—but the story started to drag and everything became too slow by the second episode. In the end, the series was dropped and the half-season ending was not even close to a real good finale. 

Next week, It's gonna be a Audrey Hepburn weekend for me thanks to Lyx!

LWP: Optical Thomas-Reiche-Kuhn sum rules

by S. M. Barnett and R. Loudon
Physical Review Letters 108, 013601 (2012)

Thomas-Reiche-Kuhn sum rules are quite important in Quantum Optics, they tell us that the sum of squared dipole moments from a any given energy level is constant in the dipole approximation. They have been useful in providing a validity check in radiation-matter interaction, like no-go theorems in the case of super-radiance in Dicke model. Anyhow, it is a necessary condition for the canonical commutation relation between position and momentum of an atomic electron to hold.

In their article Barnett and Loudon—who, by the way, have written very useful and didactic books in Quantum Optics each—explore the electromagnetic field in lossless magnetodielectric media and show that the equal-time commutation relations for the four electromagnetic field operators deliver four polariton sum rules (for the unity, permittivity, permeability and their product) analogous to the atomic Thomas-Reiche-Kuhn sum rule. They show a proof of these optical TRK sum rules by analysing the case where complex polariton frequencies are restricted to the lower half complex plane; the proof is beautiful and simple, they use complex variable analysis to state the fact that path integration in the half-upper complex planes for the four complex functions is equal to one as both the permittivity and permeability goes to one as the frequency goes to infinity, then, in the lower half, the contour integral is calculated from the zeroes of each of the four quantities corresponding to solutions of the dispersion relation for polaritons in a lossless magnetodielectric mediuml; this delivers a residue equal to one. Finally, by using a relation between residues and derivatives of the dispersion relation, they show that this residue is actually a sum over the polariton phase velocities, a little bit more of algebra and tada! They also sketch the effect of losses but leave it for a following article.

They results indicate that it is not possible to design a medium where all polariton modes are in the negative-index region. Interesting for all the meta-material research. I'm curious how this comes out in the presence of losses.

Man, oh man. I'm really dusted in complex variable. I'm still half-way in the calculations, but the paper is so beautiful written that everything seems so logical and simple.

I, the DSLR Dummy: Panoramas with Hugin

I have been trying my patience with panoramas in the last months. I have been using a nice GPL stitching software called Hugin that basically does everything by itself. It is trivial to install Hugin in any computer as there are compiled versions for unix, windows and mac. 

In the most basic mode, you select a series of overlapping pictures and let Hugin do its magic. Of course, it is a matter of taking the right pictures or calamity strikes as you can see from one of the first panoramas that I stitched:

Clarke Quay from Brewerkz, Singapore 2011.

These are some six photographs taken from an un-leveled tripod without minding the distance between the  first objects and the camera. I am a lucky guy and the result is not an eye sore but it was sheer luck that the distorted perspective came out somehow right. 

The nice thing about Hugin is that, once you level the tripod for the axis of the camera to coincide with the tripod's axis of rotation and take care for the subject to be far from the lens, it is trivial to get a nice cylindrical  projection panorama:

Harbour Front from Mt. Fabor, Singapore 2011. 

These are some eight photographs taken from a leveled and aligned tripod. Again, it was sheer luck that I got such a nice effect with the sunset at the right.  

But not everything is oats with honey, once you shoot without some stabilization or a scene that has moving parts, such as cars in a city, things get a little bit messy; for example, this one is a composition of ten pictures taken from a standing position without tripod:

Zurich Sea from Grossmunster, Zurich 2011.

I was afraid that my epileptic pulse will screw things up so I took some twenty three shoots; only ten were useful in the composition of this panorama. Even worse, Hugin didn't manage to recognize overlaps and treated the pics as independent. The good thing is that once this happens, Hugin takes you to the control point window automatically, there you can manually input control points on contiguous photographs. It seems like the best approach is to identify two sets of parallel lines, one pair of vertical and one of horizontal lines, in each pair of overlapping pics. It sounds like a hard task, but the fine tune button helps a lot in identifying the right points and it only took me around half an hour to set three hundred control points for the panorama above. I want to think that the result is not that bad after cropping it a little.

In short, for those doing this just for the sake of keeping a memory and having a hobby, or running on a tight budget like me, Hugin is a great option for stitching panoramas. It has a great automatic recognition of control points that does the work for you most of the time—so far I only had to do manual selection of control points in one out of seven panoramas—, a good selection of projection algorithms—I have only played with cylindrical projections so far— and it is for free; if you like and use it, don't forget to make a donation to the Hugin project!

I hope you enjoy your stitching as much as I do. Here are some of the panoramas I have stitched so far. 

LWP: Dicke Quantum Spin Gas of Atoms and Photons

by P. Strack and S. Sachdev
Physical Review Letters 107, 277202 (2011)

A few years ago, Nagy and collaborators proposed to use Dicke model to describe atoms in a quantized cavity driven by a classical field in one-dimension [Eur. Phys. J. D, 2008, 48, 127 - 137]. Later Baumann and collaborators experimentally demonstrated a checkerboard transition in the two-dimensional center of mass motion  of a condensate in a cavity and an optical lattice which may be described by Dicke's model [Nature, 2010, 464, 1301 - 1306]; see also Nagy and collaborators [Phys. Rev. Lett., 2010, 104, 130401]. The experiments of Baumann and collaborators realized a supersolid atomic phase with long range interactions mediated by photons. Theoretically, Dicke's model in the thermodynamic limit (the number of two-level atoms, a.k.a. qubits, is infinitely large)  looking just at the atoms delivers a phase transition in the ground state into a ferromagnet-like structure.

Here, Strack and Sachdev study what happens in Dicke model when multiple electromagnetic modes interact with the atomic ensemble without the rotating-wave-approximation instead of just the single-mode. They propose to integrate out the photonic degrees of freedom in a path integral representation to obtain a  Hamiltonian similar to the Ising model in a transverse field, where long range interactions depend inversely on the imaginary frequencies of the qubits in the path integral. They mention that such a condensed matter model is similar to the Hopfield model and allows for Mattis ground states which critical properties should be similar to those of a single-mode Dicke model but focus on the case where the long range interaction distribution is Gaussian. This, in the infinitely large number of qubits limit, allows for an extra ground state quantum spin-glass phase appart from the paramagnet and the ferromagnet known in the single-mode Dicke model. They also show that it is also possible to calculate the photon correlation function. But most importantly, discuss that the paramagnet to ferromagnet phase transition is to be considered classical while the transition to a quantum spin-glass is a genuine phase transition from the radio-frequency spectral response function of the qubits (there is a spectral weight going to zero for a continuum of frequencies in the latter case).

I really liked the paper, it is very interesting how a well-known model still delivers new ways of studying condensed matter phenomena in quantum optics setups. I'm still trying to work my way with the formalism they used to integrate out the photon fields but the good thing is that they present the procedure in the last two pages of the manuscript and it is being very helpful.

Note: I'm sorry for the one-day delay, yesterday was a public holiday and I was lazy enough to stay at home.

Epiphany

I am lucky to have met Lyx and even luckier because she choose me to share her life. 

If there's something I have to be grateful and hopeful about in this end/begin of the year, it is having Lyx at my side. She is an angel carrying a message of love and optimism, she has the patience, perseverance, faith and heart of a saint that motivates, refreshes and keeps the light bright in my darkest hours. I am sure that for every time I have wanted to look at her with murder eyes, she has had at least ten reasons to murder me and walk free but she has never looked at me with something short of a smile. 

There are things I fear, becoming sclerotic is one of those, I have never being afraid of change and yet year by year, independent of the place or time, I have developed routines that allow me to isolate my feelings and thoughts. Lyx came, saw and conquer breaking these routines without knowing. It always brings me a smile to remember our first days together exchanging music and quotes from this or that band and book that I had never heard about. Later, when we had to live in different continents, she introduced our long distance movie weekends that have kept going on for the last two years with films that have made us laugh, cry and, most important, get closer and closer. 

She is a valiant woman, I admire her. When I couldn't go back to Mexico for Christmas in 2010 she traveled for the first time out of Mexico and U.S. and came all the way to Taiwan. I was dumb enough not to book my HSRT ticket with advance and got to the airport half an hour late, there she was, all smiles, not a speckle of anger on her. 

She's strong, steadfast and optimistic while I am weak, explosive and realistic and many times i wonder how we have found that fine balance that keeps us going without stepping on each other toes. Mostly it is because of her. She has a way to accept and moderate things, to get together ends that sometimes seems opposite to each other. 

I guess she has to suffer my non-optimistic view of the world, always trying to be prepared for this or that while, at the same time, tying to get the most out of the present because you never know what will happen in a few hours. And I say I guess, because she has never complained while it seems like I am the opposite. 

She has become my love and my life and I am thankful to God for putting me in her way and made her look my way. I am lucky and thankful to be at the side of this strong, brilliant and hard working woman that has no peer to be compared to and has to suffer this fool more often than every now and then.  

Thank you God and gracias vida for your love.

Last weekend movies...

Lyx has an awesome taste in movies and again she choose one that just got us flabbergasted...

1. The Time Traveler's Wife, *****
   The whole movie is a time travel paradox of Heinlin proportions! A time traveler erratically goes back and forth in time and creates a relationship with a normal girl. It is an amazing way to tell a love story, I'm really hoping to get my hands on the book as soon as I clear my current reading list.
   
   
2. Going Postal, ****
   So far, the last film based on Sir Terry Pratchett's Discworld novels. Ankh-Morpork is suffering from a monopoly of telecommunications and needs to revive its postal service, what a better man for the job than conman Moist von Lipwig? As always, there's romance, murder, adventure and a lot of laughs.
   
   
3. Lone Wolf and Cub, ****
   I have the feeling that this one should be on the first place because I surely missed a lot of the technical, photography and cinematic details. The Ogami (similar to Okami, that is wolf) clan has been murdered in a political game during Tokugawa's shogunate, only the clan leader Itto and his son remain taking the path of the assassin and searching for revenge. An awesome masterpiece from the seventies and the first of a series of six (or maybe seven) films.
   
   
4. The Rite, ***
   A faithless man is recruited in the exorcist ranks of Vatican and confronts his first demon, Ba'al, in a faith inducing and almost mortal experience. Allegedly based in a true story
   
   
5. Red State, ***
   A trio of teens looking for sex are captured by a fundamentalist sects somewhere in rural america and there's a big screw up by the ATF. Kevin Smith—disclosure, I'm a fan of the Jersey saga—portraits fundamentalist America, both civil and government, and its screw-ups.

Most of the series have gone to hiatus so I had to go for Rafael's recommendation and some more...

1. Breaking Bad S01E01-07, ****
   Walter White, a brilliant chemist gone South surviving teaching at a high school in Albuquerque, finds himself facing death and the prospect of leaving his family without a cent and up to the neck in debts, that's when he decides to cook meth with one of his old students and break bad. In the beginning I didn't like it but as Rafael told me, it really gets worse with time and that's good.
   
   
2. Tin Man E01-03 (Miniseries), ****
   Three generations ago, Dorothy Garland walked Oz and fought the bad witches of Oz. Now, a witch is free and her grand daughters played a major role in liberating the witch. It is the turn of D.G. and a rag tag band composed of an empty-headed scarecrow of a man (a former adviser to the Queen), a heartless tin man (copper, police) and a coward lion to find a way into Oz emerald and vanquishing the witch.
   
   
3. Good Luck Charlie S01E01-23, **
   
   Charlie, short for Charlotte, is the few months old baby of the Duncan family. Her sister Teddy is video logging a diary so Charlie can learn from the past. The family is rounded up with PJ the oldest and brainless sibling and Gabe, the second youngest and the evil mind of the pack. Good innocent laughs, refreshing after so many pseudo-procedural series and good for waiting the return of Last Man Standing tomorrow night.

Happy New Year to all!

Snuff by Terry Pratchett

Snuff is the 39th novel set in the Discworld written by Sir Terry Pratchett. It belongs to the Sam Vines' (The Watch) story-arc. As every other Discworld novel, it is a treaty on humankind (read philosophy) in the form of comic-fantasy—or is it comic-fantasy in the guise of philosophy? 

In Snuff, Vimes is forced to take a vacation to the countryside where young Sam Vimes discovers the pleasures of naturalism—becoming a poo expert—and old Vimes finds himself in the middle of a murder case where he's the prime suspect. Of course, this changes immediately to old Vimes chasing the clues and upsetting a band of high-born tobacco troll drugs smugglers cashing on the status quo of rural Discworld and the perception of goblins as vermin to be enslaved and not worthy of human rights—a vision changed, in the end, by the diplomatic efforts and connections of Lady Sybil Vimes who introduces to the world the music of Tear of a Mushroom, the best student of "Where's my cow" author Miss Felicity Beedle. In this tome, Willikins—Vimes' gentleman's gentleman—plays a major role as a kind of lex-talionis-justice complement to Vimes ideal-justice and reign of the law conception of the discworld.

I am a big fan of Sir Pratchett's penmanship, it is refreshing and his books flow without any effort. More important, with his Discworld saga, he has describe many facets of historical and modern humanity exploring a great deal of the practical philosophy—including both lofty and not-so-exalted ideals—that plays a role in constructing a barely holding social weave.

I hold dear the character of Samuel Vimes, I see this know-thyself fighting-the-self-darkness hero as the embodiment of Nietzsche's aphorism #146 from Beyond Good and Evil:

"Wer mit Ungeheuern kämpft, mag zusehn, dass er nicht dabei zum Ungeheuer wird. Und wenn du lange in einen Abgrund blickst, blickt der Abgrund auch in dich hinein."

"He who fights with monsters should be careful lest he thereby become a monster. And if thou gaze long into an abyss, the abyss will also gaze into thee."

In any case, if you have never tried a book by Sir Terry Pratchett, this new year may be a good year to pick one from your local library or bookstore and give it a try.