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Two Almost Physicists With Almost Something To Say


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I Wrote A Book

I can pour liquids

I can pour liquids

Like my co-blogger, I recently, finally, finished my physics thesis. Mine took 1.333(…) years more than his because: (a) I started with my research group in my 3rd year of grad school (instead of the summer before our 1st, like he did), (b)  I did all sorts of distracting/fulfilling outreach activities for funding over the course of my years at [Semi-Prestigious East Coast University You Can Find by Googling My Name Or Looking at My Mini-Bio and Remembering Which Famous Colleges Are in Rhode Island] which diverted my attention a bit, (c) Because I am a perfectionist who also realizes that he is lazy, and therefore made every bit of code I wrote idiot-proof for the idiot I knew I would be several months after I wrote it (which turned out to be time-consuming but useful, because I was right about that idiot thing), (d) My project ended up being nearly as large as things accomplished by groups composed of dozens of astronomers—but with just me working on it, (e) Dave is smarter than me.

This picture is me pouring champagne after the confirmation (which is always obvious to everyone other than the person presenting their PhD) that it’s all good, and you’re now a Doctor. I am, conveniently, standing in front of a case displaying former department heads. Other than the guy with the cool chemistry setup on the bottom, I’m the only one who got to know that the universe is much larger than the Milky Way and that the Big Bang happened. I mean, it wasn’t a thing I discovered myself, but it’s still weird.

With one day of distance from this experience I have two major observations. The first is that the passage of time has expanded drastically since the day, weeks ago, when I submitted my dissertation. My perception of time was strongly affected by how much I’d added to my thesis, and when I spent a few days getting something to work, but didn’t contribute pages to it, I felt like I was stuck in a moment and I couldn’t get out of it. Now that I’m done, time is again like it was when I was 8 and each new day was a new world of beautiful experiences to be savored. This whole PhD thing happened yesterday and it feels like years.

Secondly is the fact that my reviewers were fine with the several snide remarks and jokes that I sneaked in there. This, in itself, is ~50% as gratifying as the whole doctorate thing itself. I quoted Donald Rumsfeld and Stephen Colbert. I wrote snide footnotes about Albert Einstein and The Dress. And it will all be on a shelf on the [Semi-Prestigious East-Coast University] Library in perpetuity. That is the sweetest victory of all.

And yes, that is a tie with constellations on it. Because I’m a fucking astrophysicist.


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Eponymity in Physics

This is a re-post of a piece I wrote on my old blog, Topography of Ignorance, back in 2007. It’s a list I compiled of the types of things you could get named after you that come in the form [Name][Type of thing], as in the word “Law” from “Moore’s Law.” There are the obvious ones like “equation” but the unusual terms are more interesting because there might be only a single example. The title is itself an adaptation of an obscure word, eponym, which I loosely interpreted to mean “anything named after someone.” I don’t think it’s a real word, and using it probably confused readers (it also could have confused them that it’s basically just a massive list with very little prose). To preserve the classic 2007 “feel” of the original post, I’m keeping the poorly-chosen title and format.  Plus, lists are now back in a big way! (What with your Buzzfeeds et al.) So it seemed like an appropriate time to bring it back. Will animate with Jennifer Lawrence GIFs as soon as I’m able…

~~~~~

A physicist wanting to make an impact on the field most often imagines his or her name attached to an Equation, or a Theory. Or even, if they really want to move mountains, a Law. I have no idea what mathematicians think about, but I would assume that they are hoping to come up with Theorems and Conjectures. Of course, not everyone is an Einstein or a Kepler, able to remake a subject and declare a Law. But if you carve out a niche for yourself, or invent a novel way of dealing with a certain topic, you’re virtually assured of getting something. For an elegant discovery, you could have an Angle named after you, or a Number. Or in a more bizarre direction, a Sea or Paradox. de Sitter has an entire Universe! Me? If I could become the first person since Isaac Newton with an eponymous Bucket I would consider myself a success. There are so many strange things you could find named in your honor that I have compiled an extensive list of them with some examples namesakes on the right-hand side.

First, some of the most common:

Equation  
Formula
 
Law
 
Theorem
 
Theory
 
Hypothesis
 
[A Unit] Newton, Gauss, Joule
[A Constant] Planck, Boltzmann
Function Riemann-Zeta, Bessel
Effect Mössbauer, Stark, Bohr,
Gunn-Peterson, etc.

And then of course, there are rarer terms. These trend very roughly from less to more obscure.

Field Fermionic, Bosonic, Higgs
Matrix Kobayashi, Cabibbo
Relation Heisenberg, Tully-Fisher
Principle Copernican, Pauli Exclusion
Model Schwinger, Bohr
Method Schrödinger
Postulate Planck, Weyl
Approximation Born
Space
Minkowski, Fock, Hilbert
Metric Friedmann-Robertson-Walker,
Minkowski
Distribution Wigner, Bose-Einstein, Fermi-Dirac
___-on Fermi, Bose
___-ian Laplace, Hamilton, Riemann
Notation Dirac
Potential Coulomb, Yukawa
Action Stueckelberg, Proca
Inequality Minkowski, Bell
Limit Chandrasekhar
Tensor Riemann
Scalar Ricci
Gauge Newtonian
Diagram Feynman
Radiation Cherenkov, Hawking
Cycle Carnot, Born
Interpretation Bohm, Copenhagen
Paradox Einstein-Podolski-Rosen,
Olber, Fermi
Problem Rabi, Fermi
Experiment Milikan Oil Drop
Spectrum Mössbauer
Conjecture Witten
Interaction Yakawa
Amplitude Feynman
Operator d’Alembert
Particle Higgs, Planck
Neutrino Majorana, Dirac
Motion Brownian
Length Jeans
Number Avogadro, Chandrasekhar, Euler
Surface Fermi
Condensate Bose-Einstein
Radius Schwartzschild, Bohr
Convention Einstein Summation
Transform Forier, Laplace
Series Balmer, Lyman
Line Lyman, Balmer
Rules Slater
Scattering Compton, Rayleigh, Thompson
Variable Cepheid, RR Lyrae
Diffusion Bohm
Diffraction
Bragg
Junction Josephson
Expansion Taylor
Manifold Riemann
Topology Picard
Mechanism Higgs
Peak Wein
Test Tolman surface brightness
Repulsion Coulomb
Epoch Planck
Parameter Hubble
[An Element]
Einstein, Fermi, Curie, Mendeleev, Lawrence, Nobel
Time/Mass/Energy/Temperature
/Density
/Power/Current/Length
Planck
Energy/Level/Hole/Velocity
/Temperature
Fermi
Wavelength de Broglie
Boson Higgs
Profile Hernquist
Criterion Landau
Rigidity Born
Cross-section Thompson
Zone Brillouin, (also see, List of Zones)
State Hartle-Hawking
Angle Weinberg
Universe de Sitter, Lemaître
Sea Dirac, Fermi
Magneton
Bohr
Splitting Zeeman
Forest Lyman-alpha
Blob Lyman-alpha
Swindle Jeans
Trough Gunn-Peterson
Window Gamow
Cage Faraday
Engine Carnot
Bucket Newton
Tuning Fork
Hubble
Golden Rule Fermi
Pancake Zel’dovich
Brain Boltzmann
Demon Maxwell
Cat
Schrödinger


If anyone else is able to repeat that last one, I will be highly impressed. I would also like to point out that the Higgs boson may be the only phenomenon or concept that has two namesakes, since the term boson originally comes from Satyendra Bose! If you can think of anything else let me know and I’ll add it.

 

Update:

Pairs       . . . . . . . . . . . . . . . . . .  Cooper

Focus      . . . . . . . . . . . . . . . . . .  Cassegrain, Nasmyth


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Observations on Observing

For once, something larger than my head in a photograph with my head.

For once, something larger than my head in a photograph with my head.

Two weeks ago I went down to Kitt Peak National Observatory in Arizona with my advisor to do some observing. Physics as a discipline isn’t really prone to sending students on trips (other than to conferences or to work with collaborators on a multi-university project), and astronomy only for observing trips like the one I just did, and consequently it was only the second time I’d gotten to travel for school/work/whatever grad school is. I did more theoretical stuff when I was an undergrad and I’ve been using archival data since I began in observational astronomy so going anywhere just hadn’t happened yet. This semester though there has been a lot of observing activity in our group, so even though it isn’t specifically connected to my thesis work, we’ve needed people to help out. In this case for a project involving star formation rates within galaxy clusters.

The 4-meter and some other 'scopes

Kitt Peak’s 4-meter and some other ‘scopes

The local environment within clusters of galaxies (presumably some aspect of its density at the point in question) has an effect on the star formation rate within the galaxies. Since there haven’t been a ton of observations of the lower rate, fainter, galaxies in clusters the idea was to come up with a method of imaging them so we could gain some insight into how many stars are forming there and why. We chose a few known galaxy clusters that are at a specific distance such that the primary emission wavelength is redshifted to be just within a narrow-band filter on the MOSAIC imager of the telescope we used (the Mayall 4-meter). Then, by comparing the difference between the narrow and wide band filters, we could pick the galaxies that were at this distance out from the background, and figure out their rate of star formation.

So that’s basically the science justification for what we were up to. Like I said, it isn’t specifically what I’ve been working on myself (though I do study galaxy clusters) so when I say “we” I really meant “the PI and my advisor” (at least in the last paragraph).

So back to focusing on me.

Kitt Peak National Observatory: Failing to detect Earth-destroying comets since 1958.

Kitt Peak National Observatory: Failing to detect Earth-destroying comets since 1958.

I had to leave from Boston at like 9am, so even though I knew I’d be up all night observing, I had to get up at like 6 am and spend most of the day in seats that weren’t designed for 6’1”, leggy brunettes like myself. We basically had to rush to get there in a timely manner, the observatory is about an hour outside Tucson, and my flight didn’t get in there until about 90 minutes before we had to get down to business

For scale, think of each letter as being the height of an average human. I would be incorrect, but think about it anyway.
For scale, think of each letter as being the height of an average human. It would be incorrect, but think about it anyway.

The telescope we were using for this project was the Mayall 4-meter at Kitt Peak. It’s a beast of an observatory— the telescope, the dome it’s in, and the structure itself, are all enormous. At least, they feel that way considering that it’s about 15 stories high and there are usually only 3 people working in there. It was built in the early 70s when the thinking was that getting any height above the ground was an improvement in seeing (the clarity of images), and so even though it was already on top of a mountain, they deliberately made it wicked tall. And to accommodate the the size of the telescope’s focal length (as you can see above) the inside of the dome, and therefore the footprint of the building had to be large as well. As it turned out, it really didn’t matter how tall it was, and in fact, giving it this massive structure caused wind coming up the side to shake the telescope a bit, which is obviously bad. Nonetheless, it’s a great instrument, and powerful enough to accurately resolve some faint galaxies.

View from the 4-meter

Reverse view from the 4-meter. You can see WIYN (the shiny metal one), the 2-meter, and a surprising amount of traffic for a mountaintop.

The first night was really painful. After having been up for about 30 hours in a row, (especially when a lot of that time consists of traveling-while-tall) everything in my body hurt, and for about an hour around 4 am my consciousness was flipping on and off like a light switch. So good job there, self. And coming out at about 6:30 am onto a freezing, surprisingly windy mountaintop was fairly painful as well. Fortunately, it was worth it since we got so much data that night. My advisor, despite working around the clock and having a couple kids, has that Margret Thatcher superpower where he only needs a few hours of sleep every day (his approval numbers are better among Scottish miners too). So luckily for us, he breezed through the all-nighter. If it had just been me, I probably would have collapsed on the controls around 4:30 and caused some kind of comical mishap.

As I said in the little science part, in addition to two common filters, we were taking images in two narrow-band filters which required us to have the shutter open for 10 or 20 minutes at a time. Once you’ve gotten set up and conditions are basically constant, and you are doing a 5-image pattern of 20 minute exposures, it definitely gives you some time to think. So I thought about how to write a python script sorting data based on header information in the files I’m using, and since I was so tired and achy, it took about 5 times as long as it should have, and involved deep thoughts about how quotation marks in certain contexts cause syntax errors.

Usually when you go from New England to Arizona in the winter, it means you don't have to look at dirty snow.

Usually when you go from New England to Arizona in the winter, it means you don’t have to look at dirty snow.

One of the cool things though about the ultra-long exposures is that they are actually long enough to detect asteroids. You see all the usual stars and galaxies, and since the exposure is so long, a higher than average number of cosmic rays, but if you look closely, there are numerous little streaks, all going in the same direction. The Earth’s motion relative to the asteroids is such that over the course of 20 min we have moved far enough relative to them that they’ve steadily moved through the background. On the third night we accidentally set the telescope to track on an asteroid, and got the reverse effect. You pick a bright guide star on each exposure and it helps the instrument to follow the field through the Earth’s rotation. It was a 13th magnitude asteroid, and the operator understandably mistook it for a star, so after 10 minutes when we saw the image, everything was streaked out, with the asteroid (and presumably all the other asteroids) looking like stars. Needless to say, there isn’t much you can do with that image.

The view up through the dome. Fortunately, there was no reason  to go up that terrifying staircase.

The view up through the dome. Fortunately, there was no reason to go up that terrifying staircase.

We were there for 4 nights and semi-fortunately, only got good data on 2.25 of them. The first was clear, the second was cloudy and we packed it in around 1am. The third it was beautiful again and we finished up two of our three clusters, and on the last night, we got just enough to deepen our exposures of one cluster. Of the clusters we wanted to see, the first was up by sunset at ~7pm, while the second only came up at 1am or so and the third a little after that. We just barely got enough for the first two. The first night we got some images of the 3rd cluster (I think) but not in enough different bands to be useful for this project.

A metaphor? For the current state of investment in basic research? Or something, I guess.

A metaphor? For the current state of investment in basic research? Or something. It looks artistic though doesn’t it?

Since I mostly work with lots of raw data, as I said, this was my first time literally operating a world-class instrument. If you don’t count outreach activities (I can put together our portable hydrogen-alpha solar telescope blindfolded like the guy in Full Metal Jacket), or TA-ing (using some kind of 1843 brick observatory full of leaves and ghosts to show undergrads that Saturn actually has rings), my experience with these kinds of telescopes was on the back-end, dealing with the imagery itself. It was somehow surprising that to take images you simply type a command into a little unix terminal window and hit “enter.” The first few times you do it you think “that’s it?” It doesn’t seem possible that this is all it takes to photograph these enormous galaxies billions of lightyears away from Earth (and simply odd to have a typed command control a physical object), but of course, years of work went into designing everything and writing the software and wiring the control system… it’s just a thing that is easy to forget in the moment.

The control room, from which, as you may guess, the telescope is controlled. And screens are looked at.

I drink a lot of ginger ale. This is a fact that's only available to H-bar Premium readers, i.e. people who read the alt-text..

This paddle that can move the telescope was next to me most of the time we were observing. Even though it is almost never used, they like to leave it plugged in and in the middle of the observer’s workspace. What could possibly go wrong?

Although the operator controls the telescope pointing, this paddle could just move the telescope over a few inches at any moment if I hit it. Good to know it was powered up and plugged in. Other than the possibility of ruining an exposure by accident, the work area was actually pretty nice. Non-astronomers who I mentioned the trip to all assumed that we were exposed to the elements somehow—that we were actually inside the open dome structure. I’m glad that we weren’t, since other than stray light getting near the mirror, it was probably about 30 degrees up there, with extremely forceful wind. Astronomy would be brutal if we had to work that way. Instead, we get to stay in a nice, warm, protected control room. Bonus points for the controls on the operator’s side of the room looking like they could have come out of a 1950’s sci-fi movie with gauges and backlit buttons.

This mirror probably has mirror envy

This mirror probably has mirror envy

After getting enough rest following the first night I set out to wander and look at all the other instruments. There was some slight awkwardness based on the fact that Kitt Peak is enough of a tourist attraction to draw people during the daytime, and though I was there as an astronomer, it isn’t like I’m carrying some “I’m supposed to be here” card that would make me feel less odd about crossing “Staff Only” signs. I mean, I did do that, but I felt weird about it.

WIYN. Shiny domes are all the rage these days.

WIYN. Shiny domes are all the rage these days.

We have a strong involvement in the One Degree Imager (ODI) at the WIYN telescope so I headed over to give it a look. Gravitational lensing studies are all about trying to get accurate, resolved, shapes of galaxies, and seeing is often the most important part of doing that. Seeing is defined as the size of stars in the image—stars are so far away that they should be points of light, but the atmosphere spreads them out, and the larger they are, the worse the image is. The adaptive optics in WIYN’s mirror, and the further corrections made by ODI, (which was only installed in the past year), takes those star images in real time and predicatively corrects the atmospheric distortions. So even though it’s not located on top of a giant windy pedestal, it’s a pretty good tool for resolving galaxy shapes. Even though it isn’t a tourist area, I figured that since I’ve been hearing about it for years and helping to write proposals involving it, I was within my rights to barge in and look around. The operator was kind enough to show me around, and despite the fact that it is a comparable instrument to the behemoth I was working in, the entire building was about the size of a large house. Here’s a picture of the adaptive optics behind the mirror that shape it to improve the focus.

WIYN100_2273

And ODI is this stuff:

The One Degree Imager, an orthogonal transfer array that stabilizes the image in real-time within the CCD. Taking a blurry photo of it is deeply ironic.

The One Degree Imager, an orthogonal transfer array that stabilizes the image in real-time within the CCD. Taking a blurry photo of it is deeply ironic.

Apparently the instrument is so quiet when it’s moving that they actually put a cowbell on it so the operators could be sure that it was actually changing position. It was over where the ODI equipment is located, but so essential that they evidentally built the new instruments around it, so you can’t actually see it anymore. (I assume that it just happens that they were able to put all the new stuff around it, but I prefer the idea that they considered it so indispensable that some planning went into keeping it there). Oddly, almost all the pictures I tried taking of it came out blurry.

WIYN's (covered) mirror, and focus

WIYN’s (covered) mirror, and focus

As you can see WIYN clearly creates some special zone of optical clarity for itself that transfers blurriness to all nearby imaging devices.

McMath-Pierce Solar Telescope.

McMath-Pierce Solar Telescope.

Schematic of the Solar Telescope. Like a potato, most of it is actually underground.

Schematic of the Solar Telescope. Like a potato, most of it is actually underground.

One of the most visually striking things up on Kitt Peak is the unusually shaped McMath-Pierce Solar Observatory. In terms of astronomical instruments it’s certainly unique. Like an iceberg or the hostility among players on a high school lacrosse team most of it is hidden below the surface. It sends light from the sun far down a long tunnel burrowed into the mountain, then reflects it back and finally sideways into an underground control room. At the time it was built this was the best way of getting magnified images and detailed spectra from the sun. Here’s a schematic:

Not knowing anyone in this field, I resisted the urge to actually go in and see the science area, but I did check out the little tourist booth where you can see the shaft and mirrors and took a ton of artsy photos of this futuristic dystopian setpiece.

Solar2

Inside the solar observatory. It's bright up there, I think I see why they put that hole in the top.

Inside the solar observatory. It’s bright up there, I think I see why they put that hole in the top.

The mirror focusing the sun's light

The mirror focusing the sun’s light

Looking down into the mountain

Looking down into the mountain

From a cool angle—it's like a giant doorstop.

From a cool angle—it’s like a giant doorstop.

100_2262

Snake times

This isn’t specific to Arizona, snakes everywhere are attracted to solar telescopes.

The radio telescope. It's some distance away from the main area, and operated remotely, so as to accommodate Jodie Foster's busy schedule.

The radio telescope. It’s some distance away from the main area, and operated remotely, so as to accommodate Jodie Foster’s busy schedule.

When I took this I though there was some kind of irony or artistic value in this photo. In retrospect, it is obviously meaningless.

When I took this I thought there was some kind of irony or artistic value in this photo. In retrospect, it is obviously meaningless.

Having done my share of aimless wandering and rested up, the rest of the trip was pretty fun. Unfortunately, the nights when we were able to get data alternated, so the second night we got nothing, the third we got a lot and on the last a storm was approaching so we only got a few hours done. There were points where we just watched the monitor as clouds were passing in front of the guide star, pausing it when it was covered, opening the shutter again when it cleared up, like the world’s most mundane video game.

One of the nights it was cloudy I went wandering around the building to check out the old equipment and aging rooms. It seems as though when it was designed, they envisioned using the building for everything, and since it’s so enormous they have all kinds of spaces there. People kept mentioning that there are creepy dorm rooms somewhere, in a way that implied that although they worked in this building, they weren’t clear on exactly where they were. Since there aren’t any windows, these terror rooms were basically small prison cells—unfortunately I didn’t find them. This is the exercise room, you can see the angular outside wall behind the state of the art exercise stuff:

The inexplicable exercise room in the 4-meter. Preserved perfectly to reflect the spirit of 1981.

The inexplicable exercise room in the 4-meter. Preserved perfectly to reflect the spirit of 1981.

They also had a bit of stuff left over from the era of photographic plates. Fortunately for us, we now use CCD cameras, but when this telescope was inaugurated it still had the old-fashioned cameras. So there were instruments for measuring sizes of objects and the astrometry between them on the photographic plates, as well as cabinets full of data, back when our data was a physical thing.

The halcyon days when astronomy filled filing cabinets.

The halcyon days when astronomy filled filing cabinets.

Light up

Don’t see many of these in high-level scientific institutions.

Going outside you really do feel like you’re isolated on top of some kind of desert ocean up there. You can’t see any signs of civilization until the nighttime, when little towns in the desert light up. I haven’t spent much time in deserts and the beauty is so striking.

Looking roughly north about an hour before sunset. It doesn't look that far up in this picture, but it really really is.

Looking roughly north about an hour before sunset. It doesn’t look that far up in this picture, but it really really is.

Weather station and the distant horizon

Weather station and the distant horizon

The mountain making a shadow on another mountain.

The mountain making a shadow on another mountain.

In conclusion: telescopes.

4-meter

The sky, and one of those things that looks at the sky.


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Physics Art Show Submission “Domeflat: SUPA00398520”

For the past few years my department has hosted an annual art show to showcase the various scientific and extrascientific artistic endeavors of students and faculty. This year I submitted a stitched-together domeflat from the dataset I’m working with—an image taken of an evenly lit telescope dome interior to better understand the imperfections of the telescope CCD. Since astronomy has a hard-earned reputation as the prettiest of the physics disciplines I thought it would really bring the hammer of day-to-day  tedium down on people’s expectations. Take THAT for assuming I’d give you something that looked good just because this is an art show! Here is the image and description I submitted:

Domeflat

“Domeflat: SUPA00398520”

This image, taken of the inside of the Subaru Telescope dome on Mauna Koa Hawaii poses the question: what is the nature of perception? Used to calibrate the properties of the telescope’s CCD cameras, the observers image a pure white field— thus, the emergent imperfections challenge the viewer to confront the fractured ways in which they view the world. Moreover, although the gaps in between CCDs create the appearance of windowpanes, the context is of a confined indoor space—a claustrophobic response to the telescope’s true potential and a visceral reminder of the futility of science to observe the substance of the soul.

The inability of the camera to detect the edges of its frame demonstrates the inner hollowness of incomplete perspective.  Are the didactic shackles of technology forcing a naturally circular field of view to be confined to a formalist rectangle? Or are we seeing a hi-fidelity instrument in a lo-fi world? What began as a white field, now viewed in ashen shades, confounds the arrêt d’annulation of the reality versus art paradigm.