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Wednesday, August 31, 2005

Why do hurricanes have names?

I remember a few years ago, while reading through the questions of one of my favorite board game Mindtrap, I came across the question "Why do hurricanes have names?"

I was in my comfortable couch in the Brookhaven Lab apartment with Patrick, watching CNN when the live coverage that Hurricane Katrina was about to strike New Orleans. At the time they were showing pictures from satellites with the evolution of the storm. I didn't pay much notice at the moment, since I knew it was hurricane season and that this event was common.

The next day I logged in into the greek news website I regurarly read, and when a foreign event is in the cover story, usually it's something big. Within a few minutes I was just astounded by the news that 80% of the city was underwater, people killed and houses relocated. And when I saw the picture of the Supedome half-torn apart, I just paused my life.

The phrase "A hurricane is coming" is not as powerful as "Hurricane Katrina" is coming.
hence scientists assing names to the hurricanes as soon as they form so that people take them seriously.

Aliens of the deep [Imax 3D] * * *

Who? Themos, Costas Z, Demetri
Where? IMAX @ The Bridge


Watching another IMAX 3D movie, I am quite convinced that this is the way that most movies will be filmed in a few years. The new applications that the 3D tehnology provides are just limitless. James Cameron (Titanic, T2, Aliens etc) is one of the major fans of the 3D technology, and in this movie here he has done his best to saw us what is it about. The movie includes magnificent shots both in and out of the water, it just never felt so real before. Now that I have a car I am not going to miss any of the IMAX 3D movies around.

Tuesday, August 30, 2005

Picasso, Kubrick and National Labs

Pablo Picasso and Stanley Kubrick are two good exxamples of what people do towards the end of their lives. Kubrick's last film was Eyes Wide Shut, a sex-driven story with lots of "intimate" encouters, orgies and impersonal sex. Picasso followed a similar route: his last works include genitals, female and male, depicted in sex situations in all kinds of combinations. Is this a message regarding that people realize what the point of life is at the end?

If this is true, what can one say about the flocks of scientists that occupy the National Labs? These labs are full of at least middle aged (usually >50 years old) people, living quiet routine lives. Maybe this is what scientists will realize is the ultimate goal of life.

Saturday, August 27, 2005

Mean Streets *

This 1973 movie (I've started to fall in love with 70s movies if you haven't realized already) is located in Little Italy, New York City. De Niro is once again excellent, same with Harvey Keitel. This is one of Martin Scorsece's first attempts, which he will later develop better. Here the movie felt like out of tune for me - although it is considered a classic. There was no coherent story, just random things happening, despite the fact that NYC never felt so realistically mean before. It was a different city back then.

Bowfinger *

Terrible... Low budget movie, Steve Martin and Eddie Murphy are wasted here. The most interesting item was the shooting at the Griffith Observatory, which I have ayet to visit. But I will really soon!

Who? Themos, Stayros, Costas Z, Demetri
Where? Demetri's divx

Wednesday, August 24, 2005

tvtvtvtvtvtvtvtvtvtvtvtvtv

CSI:Miami: Sep 19 (M)
Lost: Sep 21 (W)
CSI:NY: Sep 21 (W)
CSI: Sep 22 (Th)
The Apprentice: Sep 22 (Th)
Numb3rs: Sep 23 (F)
Desperate Housewives: Sep 25 (Su)

Google to buy Skype?

The net has been thriving with rumors the last few days regarding Google's new attack: an instant messaging program titled Talk. The program is supposed to be released soon. Also, Google made a $3billion offer to buy Skype, but it was rejected from the owners (it will just take more money, that's what I think). If they merge Skype's capabilities with a good IM software (none uses Skype for chat so far), then we will have a new strong player in the game. Google has absorbed many good talents around the market and the results have started to show up. The browser will be coming up for sure.

edit: Oups, it's out already... talk.google.com . It's a cute start, but a it has some way to go before reaching the level of the other IM services.

Tuesday, August 23, 2005

The new Intels

Intel just announced their new architectures for the new generation of processors. Finally, they focus on performance per watt rather than clock speed. Essentially they are building light, efficient processors and the desktop and mobile technologies are converging (the laptop sales just supeseed now the desktop sales for the first time ever).

The pictures from Intel's presentation along with some comments are located here.
http://www.anandtech.com/tradeshows/showdoc.aspx?i=2503

Sunday, August 21, 2005

A day without a Mexican *

2nd worst movie I've ever seen (after the Russian Ark). People listen to this: never watch a movie without having watched the trailer first! They take a ingenious idea, the disappearance of Mexicans from California for one day and rape it like crazy. The Mexicans disappear and re-appear from thin air, at random times without any explanation whatsoever. A pink fog that surrounds California and blocks internet, cell-phones, satellite signals, TV&radio broadcasts from outside? GIVE ME A BREAK!

Chinatown * * *

"LA is a small city. People talk. I don't want to become a local joke."

Jack Nicolson is a private detective in 1930's Los Angeles, when the city only had 1,000,000 people, and was facing the threat of drought in the middle of the summer. The movie just makes so much more sense when you've actually lived there. The screenplay is incredible (won oscar for that), and the wording many times left me speechless. People just don't make movies like that anymore.

Who? Themos
Where? Home Theater

The Transporter * * *

That was great stuff... Very good and original action scenes and Shu Qi is the most awesome asian chick I've seen in the movies recently. I jost love european movies like this one! I hadn't wow-ed in a movie for some time now... Or was it the 92" screen? Or both?


Who? Themos, Demetri
Where? Home Theater

Saturday, August 20, 2005

Red Eye * *



Not as good as I thought. Rachel McAdams was once again flawless to my eyes, but the whole story was way too predictable, and it is being set out right from the first 30 minutes. Yet it was watchable and never boring.

Who? Themos, Frankie, Melania, Demetri
Where? The Grove

Jay Leno, round 4

Yet another visit to Jay's show. This time I wanted to see both guests: Ralph Fiennes, who turned out to be a very shy guy that couldn't joke much. He was anxious and stressful. Then , my favorite Carmen Electra showed up.


"Carmen Electra is on the show tonight for... Who cares why?"
This girl is just so hot. I just can't believe how thinner all these celebrities are in real life.

Thursday, August 18, 2005

Testing blogger for word

Testing blogger for word

Xiaodong didn't get married

China is such an ideal country. Even if you are a citizen, you cannot get married unless you are resident there. I mean, what the f*ck? The only reason I can see behind that has to be related to the birth policy so that people don't get married there hence they don't have kids. It's perfectly ok to get married here in the US though. Huh!

Wednesday, August 17, 2005

Universal Studios

My 3rd visit to Universal Studios in Hollywood was accompanied by many fortunate surprises. I now think that this is the #1 resort for someone to go when he/she visits Los Angeles. I was happy to see that they constantly keep upgrading their shows so that they attract people back to the park. Among the new items I enjoyed were:

- Mummy: The ride. Although very short in duration, we went 3 times there and it was so much fun. I love indoor, dark roller coasters because of the element of surpise they always have. Also, this guy is the first forwards+backwards-moving roller coaster in the world, and they could only do that using electromagnetic propulsion rather than gravity (even the all-acclaimed X at Magic Mountain uses gravity). This allows for extremely new experiences: all the sudden you accelerate at high speeds while still on level ground, and after a few moments of ups and downs and turns you encounter a brick wall where you abruptly stop. While wondering what the heck is going to happen now, the same extreme acceleration forces you to move backwards through more twists and turns, while 200 speakers, water sprays and winds enhance the thrill even more. When the ride halts, it rotates 180 degrees while beimg blasted with steeming hot air before you exit. Woohoo!

- The War of the Worlds set, picture below:


I was amazed to see the set from the crashed airplane from the movie, where they dismantled a real Boeing 747. It looked so awesome.

- Only a few feet away from the airplane Wysteria Lane is located, a site that I immediately recognised since Desperate Housewives was onr of tmy favorite shows last year.

- Van Helsing's castle was ok, similar to the previous Mummy-scary type pyramid they had there.

- They have added some more extra stuff to their tours, like the rotating tunnel and the flooded Mexican city.

- Fear Factor Live was pure fun! Competition, special effects and various little gimmicks having 2000 in the auditorium was just awesome.

The classics of T2-3D, Shrek 4D and Waterworld are still amazing to watch repeatedly. Animal Planet, Back to the Future and Jurassic Park are old but nice attractions to fill the extra time. Finally, this time of the year (and weekdays!) is perfect to visit such attractions. Not too many people, and not too few. The wait times are 20min tops, while all the seats are still full.

15 GeV !

Erdem came back from the experiment at Stanford's SLAC today. They tried to accelerate electrons using plasmas, and they got the biggest known acceleration until today: 15GeV !

That's a huge number, considering that SLAC needs 3000 m to accelerate electrons to 50GeV, and we got 1/3 of this value in 10,000 less length! (0.3m of plasma)

Do I smell Nature Physics?

Back to "school"

While sitting here in my office, I can hear voices talking, phones ringing, footsteps, doors opening and closing, the elevator going up and down like crazy.

There were many times this summer that I felt I was the only person in the building. It was nice, quiet and calm. I liked it because it helps me concentrate better. But now the fall semester is about to start next week, bringing more responsibilities, noisy backgrounds and people running around in the hallways.

Speaking of responsibilities, today I have to fully review 2 of my undergrad classes, Linear Algebra and Probability theory so that I can take the placement exams tomorrow in order for me to register for the acclaimed Random Processes in Engineering course. I don't expect to pass now, but still I want to go for the experience. It's fun to watch other people suffering :-)

Tuesday, August 16, 2005

2 mathematicians are in a bar...

Two mathematicians are in a bar. The
first one says to the second that the average
person knows very little about
basic mathematics. The second one disagrees
and claims that most people can
cope with a reasonable amount of math.
The first mathematician goes off to the
washroom, and in his absence the second
calls over the waitress. He tells her
that in a few minutes, after his friend has
returned, he will call her over and ask
her a question. All she has to do is answer
“one third x cubed.” She repeats
“one thir–dex cue?” He repeats “one third
x cubed.” She asks, “one thir dex cuebd?”
“Yes, that’s right,” he says. So she agrees,
and goes off mumbling to herself, “one
thir dex cuebd…”. The first guy returns
and the second proposes a bet to prove
his point, that most people do know
something about basic math. He says
he will ask the blonde waitress an integral,
and the first laughingly agrees.
The second man calls over the waitress
and asks “what is the integral of x
squared?” The waitress says “one third
x cubed” and while walking away, turns
back and says over her shoulder, “plus
a constant!”

Monday, August 15, 2005

Myst V

I finally managed to finish Myst IV, one year after I first started playing it. The fifth and final game of the legendary series is arriving in about a month, although I don't know how will I be able to play it since it requires directx 9.0c which cannot be installed in my computer for some reason. I would bet that they will briefly revisit the original island of Myst, which we explored more than 10 years ago.

Myst IV moved along the lines of Myst III, with stunning graphics, realistic environments and usually quality riddles. For the first time a supernatural ingredient was introduced, yet in a very pleasant way. Rand Miller did a great job, having several breathtaking moments during the game. My favorite riddle: the colored door.

Saturday, August 13, 2005

17min 35sec

A great saturday morning

I am about to go to sleep now... when I wake up, two most fortunate things will have happened to me:

1. My credit line will double to $4,600 . Thanks for Katsouleas' research trips to New York, the conferences and the hotels and car rentals... woo hoo!

2. I will wake up and find a young blonde engineer girl in my home... What else can one ask for?

The Deer Hunter * * *


I hadn't watched a movie without special effects for a long time. The Deer Hunter is very weird. Although it starts off really slowly, it get very interesting as it progresses and you see how the lives of the people change after they went to Vietnam. It won best picture oscar in 1978, I think more because of the theme rather than the actual quality as a movie (which is very high level already). And the cast is best of the best: De Niro, Walken, Meryl Streep.

Friday, August 12, 2005

Simulation time

Summer is perfect for running simulations in parallel university-wide computer systems. Everyone is on vacation and the processors are always available almost immediatelly, so I feel like it's just me and a couple of other people only that use the cluster. 256 processors? No problem, sir.

My latest simulation was producing over 200GB of data so they had to kill it:-) I'll see if I can around this issue. If I lower my resolution the output may be noisy again, but I'll give it a try.

Xiaodong got married

At last, like all serious research groups around the globe, we are going to have a married phd student in our group! The chinese guy met the girl 6 months ago only, and now he went back to China with her so that their families can meet and approve the wedding. When I had asked him why is he getting married so soon, he answered "I'm 27, she's 26, and in China that's an age that people get married".

Thursday, August 11, 2005

More attempts

The method of characteristics does not work for my system of equations, it turns out they are too simple for that! I thought my system was hyperbolic but instead it is parabolic. The difference is subtle, but parabolic essentially means that the system cannot be reduced to ordinary differencial equations.

My next attempt was the weakly nonlinear approximation. This approach linearizes the equations, and produces linear PDEs instead of nonlinear, and moves the nonlinearity to the right hand side of the equations and they appear as external forces to the system.

Now I can start using Matlab to solve these equations...

Wednesday, August 10, 2005

Weekend

Friday: Dinner at Hortobagy (excellent Hungarian restaurant at Studio City), then Universal City by night. Universal City was a lot of fun, it reminds me of Times Square in NYC. Bars, restaurants, movie theaters, lots of people, live music etc etc.

Saturday: IKEA, first thing in the afternoon to get new furniture for Kostas' place. He spent $1100, exactly the money that I spent last summer for my room. Steak+eggs+pancakes at ihop, then quickly home for 30min and then off for Cat & Fiddle at Hollywood, for some new introductions.

Meanwhile I wrote the handout for lasers for our freshman EE class which turned out to be quite good I think. Then I finished the handout on Quantum tunneling, which I don't really know how good is it going to be. I went through a lot to manage to bring it down to the freshman (essentially high school!) level. Let's see what Katsouleas will think about that.

Tuesday, August 09, 2005

Jurassic park III * *


This movie was initially introduced as a B movie, and it succeds in this way. Sometimes scary, sometimes funny, without anything original though, it is quite fun. Spielberg's attempts were superior though since they actually have some interesting story to tell.

Saturday, August 06, 2005

The Edukators * *


This is definately not a Hollywood film (you'll realize why seconds after the movie starts). A young girl crashed by accident her car into an expensive Mercedes and has to pay a debt of 100,000 for the car, while working as a waitress. The movie asks how is this fair, an insignificant amount of money for such a person to destroy a girl's life.
The movie is weirdly real, the german girl is also quite impressive and the whole attempt has a strong point and a beautiful ending, although it will annoy many people.

Friday, August 05, 2005

A New Hope

After spending a lot of time in the library, google and reading, I have narrowed down my scope of research for this system of equations that I have to solve. First, I discovered that the system is not purely nonlinear, but it is quasilinear, since the derivatives come into a linear way (although their coefficients are nonlinear). Second, there is a method for reducing PDEs to ODEs, namely th emethod od characteristics which seems to be working well for first order systems. However I have failed so far to apply it to my case since I get some trivial answers - I'm not experienced enough to handle it.

The battle is not over though: I got 3 more books plus I contacted a prof in our math department plus I emailed some guys at Caltech that seem to be working on these problems, and when I get to talk to them I'm sure they will help me a lot.

Meanwhile I have to prepare within a couple of days meterial for the introduction to EE class that I will be TAing, namely on Quantum Mechanics, Lasers and Computer Networks. A long weekend lies ahead, mon amies.

Wednesday, August 03, 2005

I've reached the shore

I just realized what am I dealing with. I am trying to solve a system of nonlinear partial differential equations. Matlab, Mathematica and all these guys are useless since they can only solve standard forms of equations (at best some nonlinear of elliptic type). On top of that, my equations are highly nonlinear and nonstandard.

So I headed towards the library, to the finite island of knowledge only to get my hopes down again. There is no text on systems of nonlinear partial differential equations, apart from collections of papers (I don't want to go there yet). Of course there are plenty of books on numerical methods from scratch, but that will be my last resort. For now I left with the only text I found: "An introduction to nonlinear partial differential equations", from a guy at the university of Nebrasca.

Las Vegas things to do

After my last visit there a couple of weeks ago, Las Vegas greatly increased in my respect list. Thas was mainly because I realized there are so many many many many more things to do than I originally thought. Here's a list with that I have to do and see in Vegas in the near future, in random order:

- Cirque de Soleil: O (Bellagio) and Mystere (Treasure Island)
- Forum Shops (Caesar's Palace)
- Guggenheim Museums (Venetian)
- Luxor Architecture
- Jubilee! (Bally's)
- Fountain Show (Bellagio), viewed both from the street and the Eiffel Tower opposite
- Le Cirque restaurant (Bellagio)
- Star Trek restaurant
- Celine Dion (Caesar's Palace)
- Bellagio's Art Collection
- Atlantis IMAX-3D (Caesar's Palace)
- Adventuredome (Circus-Circus)
- Vertical Reality (GameWorks)
- Rumjungle (Mandalay Bay)
- David Copperfield (MGM Grand)
- Buffet buffet buffet (Bellagio, Paris...)
- Las Vegas Cyber Speedway (Sahara)
- Garden of the Gods (Caesar's Palace)
- Mandalay Beach (Mandalay Bay)
- Battle for Buccaneer Bay (Treasure Island)
- Olympian + Deja Vu
- Indoor Skydiving

That must be at least $1000 in entertainment and food... but hey, if you don't spend in Vegas, where are you going to spend?

Tuesday, August 02, 2005

Concerning Vonitsaneans

This post from my friend Skipis' blog is just so true... You can replace Vonitsa with many other Greek town and it will still be accurate:-)

Concerning Vonitsaneans:

The Vonitsaneans are a happy sort of people, living their simple and uneventful lives at the shores of the Amvrakikos bay. Their lives mainly involve drinking coffee at the famous local cafeteria Jeffrey-O, wetting their legs in the murky waters of Amvrakikos and sleeping a lot. One of their favorite occupations is to go on weekend nights to the Comitis club and look seriously ultra-cool according to the local mating rituals. Vonitsanean girls are very pretty but, should you ever get infatuated with one, you should know that they can get you married in 2.7 seconds. Spontaneous wedding ceremonies are known to appear out of nowhere even if there is no one of marital age around.
Another major chapter in a Vonitsanean's life is driving a car. Using the Force is an understatement for a Vonitsanean's way of dealing with the steering of a car. Basic car-dodging skills are for some generations now inherited genetically to the local offspring. Vonitsaneans also don't seem to get to grasp the notion of a pavement, so you won't be able to spot any of them.

It's insane

Our experiment is described by 3 equations: Newton's law of motion (F=ma), Gauss's law (divE=ρ) and continuity equation (D/Dt=0). These are in general 3 first order, coupled differential equations with 3 unknowns. When I tried to solve them analytically and get a single equation for one unknown function only, I quickly realized that it's pointless: I will get a 3rd order nonlinear differential equation, with derivatives with respect to both my variables, plus terms of all the possible combinations of cross derivatives, plus nonlinear terms with derivatives squared and cubed. I didn't fully derive this equation because even if I do, how the fuck am I going to ever solve it?

Hence the only solution I see is to go back to the original, simpler 3 equations and try to solve them numerically. Can Matlab do it?

Steady progress

Summer is ideal for running cluster simulation, since no one uses the processors anyway so there is very small queue and no hard drive restrictions. The last simulation I submitted will be the final one if everything goes well... It is the complete 1D problem we have, and it will take 24 hours in 256 processors be completed.

On the theoretical part, there seems to be no way to get an better analytical solution for the envelope of my differential equation. I can get one if I Taylor-expand, but it is not complete since if I add more terms to the expansion I get better answers. Hence since even with Taylor expansion I get approximate (yet closed form) answers, it is likely that I cannot get closed form exact answers.
So I move on to the next step, which is instead of solving the 1D (spatial) problem to introduce time as a second variable. This will give insight into time-dependent effects which we definitely need.

Monday, August 01, 2005

San Fran Trip

I visited San Fran once more the past weekend, and it always takes more than I expect to drive back and forth (8h and 7h respectively due to road issues). Alex's friends suggested to visit a specific place that offers breathtaking views of the Golden Gate bridge (which I crossed for the first time, at last!). Indeed, the pictures we took were awesome:



Also, I took a couple of panoramic pictures (i.e. I merged a set of pictures later to create a huge one). They are quite spectacular, since you can see all the main features of the bay area: Oakland, the Rock, downtown, the Golden gate etc. They can be found here and here (that's 10000 pixels wide!).

Another Aspect of reality - part 3

Here we will conclude the treatment of the violation of Bell's inequality. Recall that we have an experiment where 2 photons are generated with a certain (identical to each other but different from shot to shot) polarization and fly in opposite directions. At the end of their trip we set up two detectors, A and B, which can be oriented at random in any of 3 predetermined axes 1,2,3 in order to measure the polarization of the photons. We need to calculate the probability that both detectors will flash the same color, which according to Bell's inequality (from part 2) is 5/9.the detectors flash green when they detect something along the direction they are aligned, and red if they don't.


Here we will use Quantum Mechanics to prove that the probability is 1/2. We will need only 3 facts here, all of which are a consequence of QM:

1. The polarization in each photon is decided only when we measure them. Let me explain, since this is the most crucial difference: Until we measure any of the photons, we do not have any clue as to what their polarization is. In fact, the polarization is not determined until we make the measurement (hence it is not decided at the birth but only when we measure them). Also, since (as before in part 2) the photons are born correlated (identical) once we find out the polarization in one of them the other one will instantly acquire (at that exact moment!) the same polarization.
This is the spooky action at a distance that Einstein objected to. The main difference with part 2 is that the polarization is not decided at birth but the measurement itself specifies it.

2. Collapse of the wavefunction. This is a standard result of QM (Einstein was ok with that). When you make a measurement and find the polarization along a certain direction, subsequent measurements will always yield the same result with probability 1. This is because once you measure something, there is no uncertainty thereafter as to what the value is. For example, if a detector is along direction 3 and it flashes green, then any other measurement will find the same photon to be along direction 3.

Here is the critical step though: In addition, from assumption 1, the other photon will instantly be forced to have polarization along direction 3 too, even though we measured the first photon! Hence not only the measured photon will always yield again the same result with probability 1, but the other photon (due to the correlation they had from birth) will always yield the same result with probability 1 also...

At this point you should go back and read the last paragraph again since here lies the difference between the classical common sense description and the Quantum Mechanical one. In QM the measurement of the first photon will INSTANTLY force BOTH photons to align in the same direction, which is the direction of the axis of the detector. In the classic view this does not happen since the direction of the photons is predetermined at birth and it is fixed since then. Keep also in mind that the direction of the axis of the detectors is decided right before the photons hits the detector, while the other photon is far far away.

For example, we decide to put the detector along direction 1 and then we get a green light from photon A, which means that photon B is instantly also aligned with along direction 1. Then in the next shot we decide to put the detector along direction 2, and we get a red light from photon A, which means that photon B is instantly aligned opposite of direction 2 (same with photon A).


3. If the polarization of a photon forms an angle θ with respect to the orientation detector, the probability that the detector will flash green is P=cos^2(θ/2). This is a Quantum Mechanical result that I will not prove here, but I will explain how it makes a lot of sense to be that way.


Here, the photon is pointing up and the detector is along some direction A that forms and angle θ with the polarization of the photon. First, observe that cos^2(θ/2) is always positive and between 0 and 1 (like any probability!). Second, for θ=0 the detector is exactly along the polarization of the photon and hence it will always flash green (P=1). Third, for θ=180 degrees the detector is aligned opposite of the polarization and hence it will always flash red (P=0). Fourth, for θ=90 degrees, the detector is placed horizontally while the polarization is vertical, in which case there is a 50-50 chance of getting a green light. This just means that if we do the experiment with this last alignment 100 times, about 50 of them we will get a green light and about 50 of them red (This is just probabilities however; we may as well get 100 times the same light in actuality).



Now let's calculate again the probability that both detectors will flash green under this new Quantum view. For simplification let's assume that the axes that the detectors can be aligned are 120 degrees apart.

Suppose we align detector A along direction 1. When the photon is detected, let's assume it generates a green light. According to what we said in assumption 2, we instantly know now that the other photon is also pointing along direction 1. So, what is the probability that the other detector will also flash green?

Well, the detector will either be pointing along direction 1, or direction 2, or direction 3. If it is pointing along direction 1 it will flash green with probability cos^2(0)=1. If it is pointing along direction 2 it will flash green with probability cos^2(-120)=1/4, and if it is pointing along direction 3 it will flash green with probability cos^2(120)=1/4. Hence the total probability is

P = (1 + 1/4 + 1/4)/3 = 1/2

In this case we see that if Quantum Mechanics is right, Bell's inequality is violated since it says that this probability should be always greater than 5/9 > 1/2 .

Why is this result different than the common-sense answer 5/9? Because we allow for instant communication between the 2 photons, so that when the first is measured the other is instantly aligned in the same direction. Note that if you only measured instead of 3 directions just 2 (say up and down) there is no violation of the inequality (in that case Bell says P>=1/2 and QM says P=1/2 - try it). The difference is that with 2 measurement directions we know beforehand what the other detector will flash. If the first detector flashes green, the other will flash green too. If it flashes red, the other will flash red too. However with 3 measurement directions even if the first detector flashes green the second detector still has a chance of flashing red.

Before making any measurement, we predict that the probability is 5/9. After doing the measurement, the probability drops to 1/2. The action of measuring affects the probabilities of the outcomes - that concept lies at the heart of this story and transcends Quantum Mechanics.


Concluding, all these are just predictions until they are tested by experiment. In 1983 Alain Aspect did the first thorough experiment and proved that Bell's inequality was violated by 5 standard deviations. However Bell himself had pointed out that ideally the detectors had to be separated far away, so that there is no way for a signal to travel between them. Otherwise maybe after you set the detector's direction there can be a way for the photons to have predetermined at birth polarization and still get the violation answers (for example, if the detectors somehow communicate with each other). To prove the instant action from a distance, you have to have the detectors far far away.

In 1998 at team at Innsbruck generated 2 photons, fed them into optical fibers and sent them 400m apart allowing for 1.6μs of time to decide for the orientation of the detectors after any light speed signal could travel between them. Then they sat down in their computers and waited to observe a posteriori the data from the detectors. Low and behold, each time they changed the orientation of the detectors they saw a change in the statistics - that somehow the photons where communicating instantly when measured. Or better, that they are a single entity and not 2 individual items. The experiment violated the inequality with unprecedented accuracy. The paper was published in Nature the next year and Alain Aspect reviewed it.

I will end the story by quoting Aspect who mostly quotes Feynman at the last paragraph of his review:

"It has not yet become obvious to me that there is no real problem... I have entertained myself always by squeezing the difficulty of Quantum Mechanics into a smaller and smaller place, so as to get more and more worried about that particular item. It seems almost ridiculous that you can squeeze it to a numerical question that one thing is bigger than the another. But there you are - it is bigger..." Yes, it is bigger by 30 standard deviations.

Thanks to Gary Felder and his excellent article on Bell's theorem, located here.

Stealth *



This movie had a lot of noise. The writers felt they had to explain to their audience what a prime number is, but not what a quantum sponge is. The pickup line for Jessica Biel at the end of the movie had me laughing really hard:

- We are together. We are two. Two is a prime number. And prime numbers are lucky.
- Just say you love me, you pussy.

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