Metals are Shiny


“Metals are shiny.” That’s one of my favourite punchlines to end a class on electromagnetism with, and that’s what I did today. I just love bringing up a bit of everyday physics as a striking consequence of two hours worth of development on the board, and this is a good one for that. I hope the class enjoyed it as much as I did! (Basically, as you can’t see in the snapshot of my notes in the photo, those expressions are results of a computation of the […] Click to continue reading this post

Thomas and Fermi

thomas-fermiThe other day the Thomas-Fermi model (and its enhancements by Dirac and others) wandered across my desk (and one of my virtual blackboards as you can see in the picture) for a while. Putting aside why it showed up (perhaps I will say later on, but I cannot now), it was fun to delve for a while into some of these early attempts in quantum mechanics to try to understand approximation methods for treating fairly complicated quantum systems (like atoms of various sizes). The basic model showed up in 1927, just a year after Schrodinger’s […] Click to continue reading this post

Moon Line

(Click for larger view.) This was a heartening reminder that people still care about what’s going on in the sky far above. This is a snap I took of a very long line of people (along the block and then around the corner and then some more) waiting for the shuttle bus to the Griffith Observatory to take part in the moon viewing activities up there tonight. (I took it at about 6:00pm, so I hope they all made it up in time!) The full moon is at close approach, and there was a total lunar eclipse as well. Knowing the people at the Observatory, I imagine they had arranged for lots of telescopes to be out on the lawn in front of the Observatory itself, as well as plenty of people on hand to explain things to curious visitors.

I hope you got to see some of the eclipse! (It is just coming off peak now as I type…)

-cvj Click to continue reading this post


office_musings_2 Just thought I’d share with you a snapshot (click for larger view) of my thinking process concerning my office move. I’ve been in the same tiny box of an office for 12 years, and quite happy too. For various reasons (mostly to do with one large window with lots of light), over the years I’ve turned down offers to move to nicer digs… but recently I’ve decided to make a change (giving up some of the light) and so after much to-ing and fro-ing, it seems that we’ve settled on where I’m going to go.

Part of the process involved me walking over there (it’s an old lab space from several decades ago, hence the sink, which I want to stay) with a tape measure one day and making some notes in my notebook about the basic dimensions of some of the key things, including some of the existing […] Click to continue reading this post

Face the Morning…

expo_line_lady_11_sept_15With the new semester and a return to the routine of campus life comes taking the subway train regularly in the morning again, which I’m pleased to return to. It means odd characters, snippets of all sort of conversations, and – if I get a seat and a good look – the opportunity to practice a bit of quick sketching of faces. I’m slow and rusty from no recent regular practice, so I imagine that it was mostly luck that helped me get a reasonable likeness […] Click to continue reading this post

MacArthur’s Balls

macarthur_balls_cvjYou should go and see them! (Click image for larger view.) Nobody seems to be talking much about this – or I’m utterly out of touch these days since I’ve not seen a thing about this and nobody I asked seems to know either – but there’s a wonderful thing to see down at MacArthur Park. (No, it is most definitely not a cake left out in the rain, since… you know… no rain.) There are about 2500 spheres floating in the lake, and looking quite splendid, I might add. I love this highly neglected park, and so am glad that someone feels the same way and got (I read after gingerly googling “balls macarthur park” and finding this article) about 10,000 volunteers to help paint and launch these balls in an art project aimed at bringing the park back into people’s minds, at least for a while.

The panorama (click for larger view) does not do it justice, since it flattens and shrinks, by necessity, so I recommend going along and getting up close and having a look (as I ought to have done, but was on my way home in a rush and […] Click to continue reading this post


negative_mass_thoughtsSnapshot of my doodles done while talking on the phone to a BBC producer about perhaps appearing in a film discussing anti-gravity*. I explained lots of things, including why General Relativity does not seem to like negative mass, partly because they have something called a “naked singularity”, which is a big problem. Only after the call ended did I recall that in 1999 I co-authored a paper in which we discovered […] Click to continue reading this post

PBS Shoot Fun

pbs_shoot_selfieMore adventures in communicating the awesomeness of physics! Yesterday I spent a gruelling seven hours in the sun talking about the development of various ideas in physics over the centuries for a new show (to air next year) on PBS. Interestingly, we did all of this at a spot that, in less dry times, would have been underwater. It was up at lake Piru, which, due to the drought, is far below capacity. You can see this by going to google maps, looking at the representation of its shape on the map, and then clicking the satellite picture overlay to see the much changed (and reduced) shape in recent times.

There’s an impressive dam at one end of the lake/reservoir, and I will admit that I did not resist the temptation to pull over, look at a nice view of it from the road on the way home, and say out loud “daaayuum”. An offering to the god Pun, you see.


Turns out that there’s a wide range of wildlife, large and small, trudging around on the […] Click to continue reading this post

Fresh Cycle

brompton_30_08_2015I’ve been a bit quiet here the last week or so, you may have noticed. I wish I could say it was because I’ve been scribbling some amazing new physics in my notebooks, or drawing several new pages for the book, or producing some other simply measurable output, but I cannot. Instead, I can only report that it was the beginning of a new semester (and entire new academic year!) this week just gone, and this – and all the associated preparations and so forth – coincided with several other things including working on several drafts of a grant renewal proposal.

The best news of all is that my new group of students for my class (graduate electromagnetism, second part) seems like a really good and fun group, and I am looking forward to working with them. We’ve had two lectures already and they seem engaged, and eager to take part in the way I like my classes to run – interactively and investigatively. I’m looking forward to working with them over the semester.

Other things I’ve been chipping away at in preparation for the next couple of months include launching the USC science film competition (its fourth year – I skipped last year because of family leave), moving my work office (for the first time in the 12 years I’ve been here), giving some lectures at an international school, organizing a symposium in celebration of the centenary of Einstein’s General Relativity, and a number of shoots for some TV shows that might be of […] Click to continue reading this post

Red and Round…


Some more good results from the garden, after I thought that the whole crop was again going to be prematurely doomed, like last year. I tried to photograph the other thing about this year’s gardening narrative that I intend to tell you about, but with poor results, but I’ll say more shortly. In the meantime, for the record here are some Carmello tomatoes and some of a type of Russian Black […] Click to continue reading this post

Ship Building

agent_carter_team_cvj_aug_2015Last week it was a pleasure to have another meeting with writers, producers, VFX people, etc., from the excellent show Agent Carter! (Photo -click for larger view- used with permission.) I’ve been exchanging ideas about some science concepts and designs that they’re using as springboards for their story-telling and world-building for the show. I can tell you absolutely nothing except that I’m confident that season 2 is going to be really great!

(Season 1, if you’ve not already seen it, is also great. Go get it on your favourite on-demand platform – I rapidly watched all eight episodes back in June to get up to speed so that I could be as useful as possible, and it was a pleasure. It is smart, funny, fresh and ground-breaking, and has a perfect […] Click to continue reading this post

Screen Junkies – Fantastic Science!

screen_junkies_fantastic_fourHere, as promised yesterday, is the fun conversation at Screen Junkies. I don’t need to say much, since much of what I wanted to talk about (extra dimensions, other laws of physics, parallel universes, etc) made it to the (awesomely cut, btw!) episode! Embed of video below.

Enjoy! […] Click to continue reading this post

Upcoming Screen Junkies Episode Alert!

hal_dan_cvj_screen_junkies_augustYes! As you can tell from the photograph, I’ve recorded another episode with the excellent folks at Screen Junkies, and again we’ll be trying to look at some science (or science-related) issues in a movie. That’s presenter Hal Rudnick on the left, and producer/editor/writer Dan Murrell in the middle. The episode will appear tomorrow (Thursday) at around ten am Pacific, and if even a fraction of the fun (and hopefully interesting) stuff we covered makes it to the final cut (we talk for a good amount of time and then it is edited down to something short, because, you know, it’s the internet), I’ll be pleased, since we covered a lot of interesting stuff.

I’m not going to tell you what movie we talk about, but I’ll say this. The idea was that this […] Click to continue reading this post

Compton Delight

compton_effectI forgot to mention that I saw some skywriting two days ago over Los Angeles that I took to be – of course – a celebration of the Compton effect. You know, when a photon scatters off a charged particle and loses energy? That. It’s so good to see physics being celebrated so exuberantly in the public sphere**.straight_outta_physics_2


**My wife, who I was with at the time, suggested to me that it was to do with someone called Dr. Dre, but I’m pretty sure that it was Dr. Compton who discovered that phenomenon, so I gently explained the discovery to her. Click to continue reading this post

Parting Shot

Museo_historico_nacional_santiago_chileWednesday was my last day in Santiago, and so after the morning Plenary talks I checked out of my hotel, stored my bag, and, boarding the subway, melted into the city for a few hours. I was not on the lookout for anything in particular, besides a sense (even a little) of the city’s life and flow. I also had in mind to spend a few hours at some galleries/museums (I’d already seen the Museum of Pre-Columbian Art (Museo Chileno de Arte Precolombino) on Monday night, and had a tour, as that’s where the conference reception was). I wanted to check out the Museum of Contemporary Art (Museo de Contemporaneo Artes) and Museum of Fine Arts (Museo de Bellas Artes), as well as the Museum of National History (Museo de Histórico Nacional), back in Plaza de Armaz, where I’d done that cafe and Post office sketch on Sunday. I also wanted to wander the streets and squares and just look at the people and buildings and goings on. And then I had to get back to the hotel at 6:45pm to grab my bag and jump into the taxi I’d ordered and head to the airport for my flight back to LA.

Well, I did pretty much all of those things, with no hiccups to speak of. I was a little annoyed that 95% of the Museum of Contemporary Art was taken up by a massive David LaChappelle retrospective – not because there isn’t something in his work one can find to like or at least be amused by (I had a good look around since I was there), but because it seemed ridiculous to have flown almost 1/3 the way around the planet to see an American artist’s work when what I wanted to see was work that was more local – but all turned out ok when in the Museum of Fine Art (the adjoining building in fact) I found a great deal of interesting contemporary (and other) art that was locally sourced. The buildings themselves were interesting to look at too, so that was a bonus.

On a nearby street (Monjitas), I found a great spot for lunch and people-watching, and the woman who I took to be the proprietor of the cafe (who took my order) decided to engage me in conversation for while. Since she had little […] Click to continue reading this post

Almost Done

So Tuesday night, I decided that it was imperative that I paid a visit to one really good restaurant (at least) before leaving Santiago. My duties at ICMP2015 were over, and I was tired, so did not want to go too far, but I’d heard there were good ones in the area, so I asked the main organizer and he made a recommendation.

imageIt was an excellent choice. One odd thing: the hotel is in two separate towers, and I’d noticed this upon arrival and started calling it The Two Towers in my mind for the time was there. Obviously, right? Well, anyway, the restaurant is right around the corner from it plus a two minute walk, and…. Wait for it…it is called Le Due Tonni, which translates into The Two Towers, but apparently it has nothing to do with my observation about the hotel, since it got that name from a sister restaurant in a different part of town, I am told. So… An odd coincidence.

I will spare you the details of what I had for dinner save to say that if you get the fettuccini con salmon you’re on to a sure thing, and to warn that you don’t end up accidentally ordering a whole bottle of wine instead of a glass of it because you’re perhaps used to over-inflated wine prices in LA restaurants (caught it before it was opened and so saved myself having to polish off a whole bottle on my own)… Another amusing note is that one of my problems with getting my rusty Spanish out for use only occasionally is that I get logjams in my head because vocabulary from Spanish, French, and Italian all come to me mid sentence and I freeze sometimes. I’d just been getting past doing that by Tuesday, but then got very confused in the restaurant at one point until I realized my waiter was, oddly, speaking to me in Italian at times. I still am not sure why.

It was a good conference to come to, I think, because I connected […] Click to continue reading this post

Existence Proof

imageThe picture is evidence that bug-free Skype seminars are possible! Well, I suppose it only captured an instant, and not the full hour’s worth of two separate bug-free talks each with their own Q&A, but that is what happened. The back story is that two of our invited speakers, Lara Anderson and James Gray, had flight delays that prevented them from arriving in Santiago on time and so I spent a bit of time (at the suggestion of my co-organizer Wati Taylor, who also could not make the trip) figuring out how we could save the schedule by having them give Skype seminars. (We already had to make a replacement elsewhere in the schedule since another of our speakers was ill and had to cancel his trip.)

Two Skype talks seemed a long shot back on Sunday when Wati had the idea, but after some local legwork on my part it gradually because more likely, and by lunchtime today I had the local staff fully on board with the idea and we tested it all and it worked!

It helps that you can send the whole of your computer screen as the video feed, and so the slides came out nicely (I’d originally planned a more complicated arrangement where we’d have the […] Click to continue reading this post


imageI’m in Santiago, Chile, for a short stay. My first thought, in a very similar thought process to the one I had over ten years ago in a similar context, is one of surprise as to how wonderfully far south of the equator I now am! Somehow, just like last time I was in chile (even further south in Valdivia), I only properly looked at the latitude on a map when I was most of the way here (due to being somewhat preoccupied with other things right up to leaving), and it is a bit of a jolt. You will perhaps be happy to know that I will refrain from digressions about the Coriolis force and bathtubs, hurricanes and typhoons, and the like.

I arrived too early to check into my hotel and so after leaving my bag there I went wandering for a while using the subway, finding a place to sit and have lunch and coffee while watching the world go by for a while. It happened to be at Plaza de Armaz. I sketched a piece of what I saw, and that’s what you see in the snap above. I think the main building I sketched is in fact the Central Post Office… And that is a bit of some statuary in front of the Metropolitan Cathedral to the left. I like that the main cathedral and post office are next to each other like that. And yes, […] Click to continue reading this post

Page Samples…!

second_set_samples_editThere’s something really satisfying about getting copies of printed pages back from the publisher. Makes it all seem a bit more real. This is a second batch of samples (first batch had some errors resulting from miscommunication, so don’t count), and already I think we are converging. The colours are closer to what I intended, although you can’t of course see that since the camera I used to take the snap, and the screen you are using, have made changes to them (I’ll spare you lots of mumblings about CMYK vs RGB and monitor profiles and various PDF formats and conventions and so forth) and this is all done with pages I redid to fit the new page sizes I talked about in the last post on the book project.

Our next step is to work on more paper choices, keeping in mind that this will adjust colours a bit again, and so forth – and we must also keep an eye on things like projected production costs and so forth. Some samples have been mailed to me and I shall get them next week. Looking forward to seeing them.

For those who care, the pages you can see have a mixture of digital colours (most of it in fact) and analogue colours (Derwent watercolour pencils, applied […] Click to continue reading this post

Ian McKellen on Fresh Air!

Ian McKellen twitter profile imageI had a major treat last night! While making myself an evening meal I turned on the radio to find Ian McKellen (whose voice and delivery I love so very much I can listen to him slowly reading an arbitrarily long list of random numbers) being interviewed by Dave Davies on NPR’s Fresh Air. It was of course delightful, and some of the best radio I’ve enjoyed in a while (and I listen to a ton of good radio every day, between having either NPR or BBC Radio 4 on most of the time) since it was the medium at its simple best – a splendid conversation with an interesting, thoughtful, well-spoken person.

They also played and discussed a number of clips from his work, recent (I’ve been hugely excited to see Mr. Holmes, just released) and less recent (less well known delights such as Gods and Monsters -you should see it if you have not- and popular material like the first Hobbit film), and spoke at length about his private and public life and the intersection between the two, for example how his coming out as gay in 1988 positively affected his acting, and why…. There’s so much in that 35 minutes! […] Click to continue reading this post

Goodbye Nambu

nambu-gotoOne of the towering giants of the field, Yoichiro Nambu, passed away a short while ago, at age 94. He made a remarkably wide range of major (foundational) contributions to various fields, from condensed matter through particle physics, to string theory. His 2008 Nobel Prize was for work that was a gateway for other Nobel Prize-winning work, for example 2012’s Higgs particle work. He was an inspiration to us all. Here’s an excellent 1995 Scientific American piece (updated a bit in 2008) about him, which nicely characterises some of his style and contributions, with comments from several notable physicists. Here is a University of Chicago obituary, a Physics World one, one by Hirosi Ooguri, and one from the New York Times. There are several others worth reading too.

Since everyone is talking more about his wonderful work on symmetry-breaking (and rightly so), I’ve put up (on the board above) instead the Nambu-Goto action governing the motion of a relativistic string (written with a slight abuse of notation). This action, and its generalisations, is a cornerstone of string theory, and you’ll find it in pretty much every text on the subject. Enjoy.

Thank you, Professor Nambu.

-cvj Click to continue reading this post

To Fill a Mockingbird

baby_mocking_birds_1Meanwhile, here at the Aviary (as we’re calling the garden because of the ridiculously high level of bird activity there has been in the last few months) there has been some interesting news. Happy news, some would say. This is hard for me since it is all about my arch-nemesis (or one of them) the Mockingbird. Many hours of sleep have been damaged because of them (they do their spectacular vocal antics during both night and day – loudly), and there seems to be more and more of them each year. I’ve been known to go outside (in various stages of undress) in the wee hours of the morning and thrash long sticks at parts of trees to chase persistent offenders away.

Well, we’d noticed that a particular spot in a hedge was being visited regularly some weeks back, and guessed that there might be a nest in there. Then one day last week, two juvenile mockingbirds emerged, practicing their flying! I knew immediately what they were since they have the same markings, but their feathers still have those fluffy/downy clumpiness in places, and of course they were not nearly as acrobatic as their adult counterparts. They hung out on […] Click to continue reading this post


No expense spared on astronomy graphics here, you’ll notice. (This is the Pluto-less hanging mobile that amuses my son every morning when he wakes up. At least I think it is supposed to represent our Solar system in some vague way… in any case, it is a very pleasant object to look at for both him and me.)

Just in case you’ve not been following the exciting news, let me remind you to look out for the new information arriving from the New Horizons mission to Pluto. tn-p_lorri_fullframe_color The craft has done its closest approach now, and later tonight will start sending the best of the images and other data about the Pluto system. A huge amount has been learned already in the days leading up to today, as you can get a sense of by looking here. Earlier today, the lovely image to the right (credit: NASA/APL/SwRI – click for larger view) […] Click to continue reading this post

Marginal Activity

The last couple of weeks have seen me fiddling with another important task for the book: rethinking the page dimensions. This gets me into things like crop points, safe areas, bleeds, and so forth. It is sort of crucial that I worry about this now and not later because for the kind of book I am working on, every single page is a unique self contained entity that must be designed individually, while at the same time each page still depends on all the other pages to be just right. So a change in page dimensions is a huge deal in the process. This is not like writing large blocks of prose in the form of chapters and paragraphs, where the page dimensions are less crucial since your words will just flow and re-flow automatically to adjust to the new shape of container (the page), newly spilling over to the next page if need be. Instead, graphic elements -the drawings- all must work together on a number of different levels on the page, their relative positioning being crucial, and any text that is present must also respect that layout… In fact, text is really just another graphic element on the page, and is not as malleable as it is in a prose book.

sample_exp_iv (Random sample from a story I’ve just completed the roughs for in the new dimensions. You can see the red guide lines I work to to make sure that the page comes out fine at the printer, the inner being the “safe area” beyond which you don’t put any crucial elements like text in case they are cut off. The outer is the line where the page should end. Some of my pages have “bleeds” which means the art will flow all the way past that outer line so that when cropped that part of the page is covered entirely with art instead of it stopping due to a panel border…)

I say all this because it is an issue close to my heart right now. Back when I did all the art for the prototype story (some years ago now), and right up to last year, I did not yet have a publisher for the book, so therefore of course no idea what the final page dimensions might be. Different publishers have different favourites, print capabilities, and so forth. So I made the best decision […] Click to continue reading this post

Dune Love…

goodnight_dune_julia_yuI ran across two excellent Dune-related items in the last fews weeks, and since it is the 50th Anniversary of Frank Herbert’s book “Dune”, I thought I’d share them with you.

The first is on the really excellent website called Pornokitsch, which I’m delighted to introduce you to if you’ve not encountered it before. (Don’t worry about the name – they chose it ironically.) Bookmark it and repeatedly return for more. This piece on Dune was about the David Lynch film, really (and not too much about the book), which is always great to discuss with people since it inspires intense love and hate in people… sometimes both in the same person. I find it a decidedly flawed film with so many delightful charming oddities that I can’t help but enjoy it. A number of regulars weigh in […] Click to continue reading this post

Lost Treasure

very_rough_pageStill doing detailed layouts for the book. I’ve been working on a story for which I was sure that I’d done some rough layouts a long time ago that I really liked. But I could not find them at all, and resigned myself to having to do it again. There’s always that moment of hesitation where one is poised between just diving in and re-doing something, or spending more time searching… Which is the better strategy to save time? This time, I thought I’d do one last look, and started to dig around in my computer, hoping that maybe I’d had the sense to scan the sketches at some point – I vaguely recall having made a policy decision to scan developmental sketches whenever I could, for ease of […] Click to continue reading this post