Sunday, May 21, 2017

Another year, another edition of... THINGS Jonathan P. Dowling SAYS IN CLASS:


You can’t see day with the lights off.

Don’t ever ask a Dutch person to pronounce Huygens because they will spit on you.

Infinity minus infinity equals negative twelve. We will prove this rigorously.

Only when Dowling the Great teaches this course does the second semester run, because I am ever popular.

What we proved here by eyeball in two lines, I reproved here by eyeball in 26 lines.

In D.C. there was a bank robber, John Dillinger. When they asked why he robbed banks, he said that’s where the money is. When they ask me why I go to D.C., that’s why… to rob banks.

Depending on who you ask, there is either infinite energy or zero energy.

What I’m going to do now is strike fear into your young hearts.
 
Hold on my phone just made a weird sound…(checks phone)… 30 seconds to impact.

I’ll torture you only a slight amount.

I’ll give the half-ass proof. The zero-ass or full-ass proof requires much more work.

In quantum optics we brush the infinities under the rug at the beginning. In QED you stare at the infinities for a while then brush them under the rug at the end.

I can do whatever I want because someone will complain no matter what.

This is standard procedure, which means you don’t question it and just do it.

Aha! Three is equal to three!

It’s not mysterious, it’s optics!

The density operator allows you to combine all that is horrible about QM and all that is horrible about stat mech into horrible squared. But if horrible is less than one, that is an improvement.

My goal this semester will be to get … what’s his name… to laugh.

Whenever you see something you don’t like, put a hat on it.

What color is math? Math is purple.

Limbo is like heaven, but you don’t get to see the face of God.

Hell will come sooner than you expect, but not right now.

I want to give some more meat to the blob.

Teaching is the science of ever-improving lies.

This should be familiar from statistical mechanics, or S&M as we used to call it.

The point of physics is to embarrass yourself over and over again until you just don’t care anymore.

There’s actually a journal of irreproducible results. I submitted a paper there and it got rejected. I’m not sure if I should be happy or upset.

I’m on antibiotics and decongestants. I can literally hear the boogers popping in my head. It’s delightful.

He didn’t have a computer so he used a pyramid of male hair dressers.

You have to choose between mentoring, tormentoring, and dementoring.

Never go to third order perturbations unless you hate your own existence and want your life to end.

Beer’s law: if you have too much beer, there is no law. …which was proved by Galois the night before he died in a duel over a prostitute. But that’s another story.

That’s perfect! I need to make it crappy, so I put in a crapization factor.

The sun is not a telegraph.
 
Now you have known me for several weeks. You know that I lie!

First, LIGO’s laser goes through a mode cleaner. It’s like a vacuum cleaner; cleans up the vacuum.

They’re just beamsplitters! Everything is BS in this course, which you should have learned on day one.

Your grade this semester will depend on whether or not you register for next semester.

Now this is up to convention which means it varies from book to book and also that I will do random things from class to class depending on how I feel.

The whole point of the previous discussion was to prevent that question in the first place. Please go back in time and don’t ask that question.

Jon:…we have to start off easy because you can still drop the class until Monday.
Student: We can still drop the class today, you know
Jon: I can still not sign your paychecks for another year when the grant runs out

We have a lot of sandwiches. It’s time to go to lunch. We have to knock off some of these sandwiches. …but if you have trouble just turn one sandwich into two sandwiches and then you’re less hungry.

We use the regular rotation matrix that you will recall from kindergarten.

This is simple, it’s just Pac-man sandwiches.

The phase-state is an infinitesimally thin, and infinitely long slice of phase pizza. It’s not known whether it’s filling or not.

…n-bar is this function, which could be anything since you can’t read it.

[long story about making soap chips back into bars by placing them in plastic containers to be microwaved]

When you make a sandwich, you have to—tediously—pull something interesting out of it.

We’re going to start with the half-ass theory, then move to the quarter-ass theory, on to the one-sixteenth ass theory and so on until the no ass theorem, which I assume is the best.

I feel like I was run over by a truck, and then people dumped coffee on me.

Saturday, May 20, 2017

#WIDOMSUMVAC — SHANGHAI DAY SEVEN


As promised the highlight of the week was visiting the labs of Profs. C.-Y. Lu and J.-W. Pan at USTC Shanghai. Prof. Lu was our gracious host.

LSU-NYU-USTC Collaboration!

Upon arrival, me, Tim Byrnes, and students Chenglong You, Sushovit Adhikari, and Naeime Mohseni, watch some slides and videos of the satellite in action including the pointing and tracking carried out by several laser beams.We then gave a presentation on our latest results on quantum metrology.

 Chinese quantum satellite in action — pointing and tracking. 
Red goes up from ground and green comes from satellite.

  Chenglong explains quantum metrology and we propose a new experiment.

The satellite is able to carry our Earth to Space quantum cryptography as well as distributing entanglement to remote round stations as tests of quantum theory over large distances. Apparently the satellite is responding much better than anticipated and they will publish data soon.

I had promised the students we would see the duplicate of the quantum Chinese satellite Mozi, but when we went into the satellite assembly room in quite a funny moment Prof. Lu threw up his hands and yelled, “WHERE IS THE SATELLITE!?” Apparently it had been moved to a new location the night before.

 Where is the satellite!? Chenglong "The Photo Bomber" (left) and Prof. Lu (right).

 What it looked like before it went missing.

After losing the satellite we had a tour of the cold-atom labs and then the photonics lab where LSU is collaborating with USTC on experiments on boson-sampling-inspired quantum metrology. The experiments are finished so expect exciting results soon. 

Sodium lasers cool and trap the atoms. Chenglong bombs the photo.
Lab tour at USTC: Chenglong, Sushovit, Tim.
The boson sampler in action. The foggy plate is an all optical quantum computer.
Lasers the run the show.

They won't let me push any buttons!
Then after the lab tours we were all invited to a nice dinner by Prof. Lu and we toasted to future collaborations — Gānbēi!

The stuff in the glasses is maotai which was used to fuel the rocket that launched the satellite.




Wednesday, May 17, 2017

#WIDOMSUMVAC — SHANGHAI: DAYS THREE–FOUR

I have begun to realize most of my photos show us eating and drinking and don’t provide any evidence that I’m even here. The problem is that during chaos time I’m always talking and thinking and forgetting to take any photos.
Me — too busy thinking.

Since my LSU PhD student, Chenglong You, says I take terrible photos, and he is always talking without thinking, I have nominated him the official photographer for the Shanghai leg of my blog.

And Chenglong says I take a bad photo?

Sushovit smug shot. 

 Who takes a bad picture?

So today I have some more photos! As usual we met for Chaos time at 1:30PM after lunch and worked until 6PM then took Naeime Moshseni, my Iranian co-PhD student, to the local halal restaurant and had lots of lamb and other fantastic things while we watched traditional folk dances from the Chinese province of Xinjiang.

 Tim's postdoc Chandra and his daughter, Manasvi, and wife, Ramya, at lunch.

During chaos time we discussed endlessly Einstein’s synchronization protocol (ESP) for clocks and then Tim’s research associate, Chenyu Zhang, told us all about her latest work on quantum teleportation (with a twist) — a collaboration with the laboratory of the famous Prof. Jeff Ou — of Hong-Ou-Mandel fame — at East China Normal University.

On a clear day you can see downtown Shanghai.

A handmade box filled with goodies given to my by my Co-PhD student Naeime Mohseni.

 Tim Byrnes and me arguing endlessly again.








 Is it fun to stand in front of a whiteboard for hours arguing physics? You bet!


You can't tell a porter anything.


NYU Freshman orientation?





At the halal restaurant.

Thursday (tomorrow) Naeime will present all her recent work on atomtronic theory with ions.

Stay tuned!

Monday, May 15, 2017

#WIDOMSUMVAC — Shanghai: Day Two

Got up at 8AM sharp and dived into the lovely breakfast buffet at my Shanghai Tongmao Hotel, which is delightfully located across the street from NYU Shanghai, and I arrived at my office at 10AM. The lovely thing about the 13-hour time difference is that about noon here is about midnight at LSU, and all the emails stop in time to go to lunch. 

 An interesting lunchtime option at the NYU cafeteria.


Lunch with Byrnes Group. 
LSU PhD Students Chenglong You and Sushovit Adhikari left front.

Then I caffeinate up at the Starbucks with a tall flat white (double-tall-wet cappuccino) and then chaos time commences at 1:30PM where we hammered out over 10 new research project ideas in four hours and still had time for LSU PhD students Chenglong You and Sushovit Adhikari to give a presentation on their work on boson-sampling-inspired quantum metrology, some of which has just been beautifully verified in the lab of Profs. J. W. Pan and C.-Y. Lu at the University of Science and Technology of China (USTC). We’ll be visiting the USTC Shanghai campus on Friday to hammer out new research directions and experimental collaborations.

 Chaos time is carefully scheduled.

Then after brainstorming for four hours (storm>>brain) we generated over 10 topics to work on over the two weeks I'm here. Typically by the end of the two weeks we have whittled those ten to about two where we have enough of an idea how to proceed to begin fleshing them out and eventually publishing them in a journal.

LSU PhD student Sushovit Adhikari summarizes all the ideas for research projects.

After the storm subsided, we retired to the Blue Frog for happy hour and continued discussions before heading out to the local Szechuan restaurant for spicy food and a traditional Chinese “face off” dance. 

 The frog is blue like Eric's shirt! Tim Byrnes to left and his students Eric Song and Louis Tessler.


 LSU PhD student Sushovit Adhikary warily eyes the fried chicken on a stick. "Who gets to eat the head?" he wonders.  In the end LSU PhD student Chenglong You beats him to it. In the back is Tim's postdoc,  Ebubechukwu Ilo-Okeke, and Research Assistant, José Eduardo Cejudo Grano de Oro.

My co-PhD student, Naieme Mohseni, and Tim's research assistant, Chenyu Zhang,  
discuss quantum physics and the meaning of the universe.

I show Naeime how to use chopsticks — the wrong way!

 I challenge Tim Byrnes to a duel with chopsticks.

 The plans for the next two weeks are set and Tuesday we begin calculations in earnest. In a great collaboration my student Naeime Moseni from Iran, who I am co-PhD supervisor of, is here for a month visiting the Byrnes' group and we have a chance tomorrow to respond to the referees of our Physical Review A paper, and plan the research projects for the next year.  It is all very international here and all very exciting.



Sunday, May 14, 2017

#WIDOMSUMVAC — Shanghai: Day One


Arrived about 2:00PM SUN 14 MAY on the 15-hour flight from Dallas (DFW), to the Shanghai International Airport (PVG), remarkably rested as I managed to sleep 10 hours on the plane. How do I do it? (Sleep on the plane.) Well after years of experimentation, I have the following protocol. My flight from Baton Rouge (BTR) to DFW left at 6:30AM, so I had to leave for the airport via my trusty shuttle driver Faze (for whom the Faze uncertainty is below the shotnoise limit) and so I simply did not sleep at all Saturday night.

My flight arrived at DFW around 9:00AM on SAT 13 MAY, and then my flight from DFW to PVG left DFW at 10:30AM, which is about 11:30PM in Shanghai (then next day) and time for me to go to sleep at my destination so that is when I must go to sleep on the plane. After the plane takes off they have a drink service so I take a melatonin, a sleeping pill, and two Benadryl tablets with a glass of wine, and then (with dinner) I have another glass of wine, and then it’s less like going to sleep and more like going into a drug-induced coma.

In the plane they give you a small pillow and blanket. I place the blanket on the seat for more cushioning and the small pillow under my lower back for lumbar support. Then — and here is the trick — I place those small foam earplugs in my ear canals, and then my over-the-ear Bose noise-cancelling headphones on top of that. This acts as a dual spectrum filter. The headphones are designed to kill off low-frequency sound like engine noise but are hopeless at the high frequency of people talking or babies crying. The foam earplugs handle the high frequency. Then on goes the eyeshade thing, and I use my jacket for a blanket — and then I have almost complete sensory deprivation. The system cannot handle smell or touch, so if the person next to you wears weaponized cologne or the toddler behind you decides to kick the back of your seat for 15 hours (with weaponized sneakers), then you may be out of luck.

 Chenglong and his sign at the airport.

I’m now a pro at using WeChat (WhatsApp for China) and my LSU PhD student Chenglong You was there to meet me at the airport (he having arrived a couple of days earlier to carry out advanced reconnaissance). I told him to hold up a sign with my name after baggage claim, but he did not (claiming I would be easy to spot even if by the sound of my voice alone), and so I handed him an old conference nametag from my computer bag and made him hold it up for a proper photo-op prop.

Then using the Chinese ride service DiDi (the Chinese Uber), Chenglong scored a nice ride to my hotel for only about $7US. (If I had instead used one the shady illegal taxis, whose salespersons stalk the airport like vultures, it would have been $70US.) The ride took about an hour and Chenglong and I planned what physics to do in the next two weeks. To return the favor for the ride, after checking into my hotel, I treated Chenglong to dumplings (jiǎozi) for lunch and then picked myself up some beer and pistachios for dinner, at the local equivalent to the 7-11. 

 Chenglong's dumplings.


It is now nearly 8PM on SUN 14 MAY and the meetings with Tim Byrnes’s group at NYU Shanghai start tomorrow. My second LSU PhD student, Sushovit Adhikari, arrives around 11PM tonight from Katmandu via Chengdu, and Chenglong the Merciful, is back to the airport to meet him. 

Tim holds daily group meetings for his postdocs and students that he calls “Core Time” but these are cancelled for the two weeks that I am in town, and we change it to “Chaos Time” where we all argue with each other, write equations on the white board, read papers on the big LCD screen, and brainstorm up all the ideas in week one. Then in week two we write them all up and I leave. Sushovit and Chenglong will stay on for another six weeks to collaborate with Tim and his group and continue project of joint collaboration. This is how I insure LSU PhD students in physics get an international training.

As my Chinese students tell me the only word in Mandarin I can pronounce perfectly is beer (píjiǔ) — which since I’m Irish what did you expect? — and so with one bottle of Tsingtao beer and some pistachios sitting here next to me as I type I expect the lords of jet lag to take me soon. Thank the lords of caffeine there is a Starbucks just outside the front door of my hotel next to NYU Shanghai for the AM Chaos Time.

 Chinese cure for my jet lag.

 

Tuesday, May 9, 2017

This Ain't Yer Gradma's Squeezed Vacuum!?

Multi-pass configuration for Improved Squeezed Vacuum Generation in Hot Rb Vapor

We study a squeezed vacuum field generated in hot Rb vapor via the polarization self-rotation effect. Our previous experiments showed that the amount of observed squeezing may be limited by the contamination of the squeezed vacuum output with higher-order spatial modes, also generated inside the cell. Here, we demonstrate that the squeezing can be improved by making the light interact several times with a less dense atomic ensemble. With optimization of some parameters we can achieve up to -2.6 dB of squeezing in the multi-pass case, which is 0.6 dB improvement compared to the single-pass experimental configuration. Our results show that other than the optical depth of the medium, the spatial mode structure and cell configuration also affect the squeezing level.
Comments: 7 pages, 8 figures
Subjects: Atomic Physics (physics.atom-ph); Quantum Physics (quant-ph)
Cite as: arXiv:1705.02914 [physics.atom-ph]

Monday, May 8, 2017

MON 08 MAY 2017: What I Did On My Summer "Vacation" #WIDOMSumVac

Four days and counting before I depart for Shanghai, China, on SAT 13 MAY via BTR-DFW-PVG (the airport codes for my trip: Baton Rouge – Dallas – Shanghai).

I will be for two weeks primarily visiting the group of Prof. Tim Byrnes at New York University ... Shanghai! I now have a pseudo-neo-formal post at the place, and we'll continue our several-years-long collaboration on theoretical quantum technologies, the most recent of which resulted in a paper on relativistically invariant entanglement distribution in space.

Each day I arrive at my office at around 10–11AM and do email until lunch time and then after chugging a double espresso after the neighboring Starbucks we all meet in a conference room for “core time” until around 7PM with the postdocs, other visitors, and student. Core time is nicknamed “chaos time” when I am there and we hammer out ideas on the white board and the computer projector in week one, and then write them all up in week two.

Upon my arrival I always yell, a la mathematician Paul Erdős, “My brain in open!”

Then the fun begins.

This year I’ll be accompanied by two of my LSU PhD students, Chenglong You — I only have Ayes for You! — and Sushovit Adhikari, who will stay on after me for another six weeks in Shanghai to further the collaborations.

In addition to NYU I’ll be visiting the laboratory of Profs. J. W. Pan and C.Y. Lu at the Shanghai branch of the University of Science and Technology, China, where great things are afoot — not to mention the famous Chinese quantum satellite, which was launched last August. Lorentz invariant quantum entanglement distribution, for this satellite, we had in mind.

When in China do not forget my honorary Chinese name,

建道灵

Jian Dow-Ling

Which means, “Spiritual Alliance” or “Dowling’s Construction Company”, depending on context.