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Ultimate Scientific Distillations: Deep insight, simple representations

by Andre on 15 June 2007

At its best, the scientific method can reduce profound questions about our universe to their barest essence and answer them compellingly with simple observations. The greatest experiments achieve the most complete distillations because of the principles and theories that guide them and the knowledge that has already been well established. Once this context is internalized, even grainy images or barely visible spikes in a line of noise can become moving pieces of art.

Here’s the image that got me thinking about this most recently:

It’s a postcard that Walther Gerlach sent to Niels Bohr after Gerlach’s experiment seemed to confirm Bohr’s prediction about the magnetic moment of atoms. The caption says “Attached [is] the experimental proof of directional quantization. We congratulate [you] on the confirmation of your theory.” According to the delightful Physics Today article where I found this figure, at the time these results were considered “among the most compelling evidence for quantum theory.” This is an amazing distillation. Magnetic field off, no splitting. Magnetic field on, splitting. Magnetic moment is quantized. For background, some complications, and to learn about how cigar smoking in the lab played a crucial role in this discovery you’ll have to read the article.

I don’t want to talk about the details of the experiment here though. Instead I want to ask for other great scientific distillations. There must be excellent examples of this from the early days of molecular biology. Something like: this spot is radioactive, this spot is not, so DNA is the molecule of inheritance. Let’s see your nominations. Include a link to an image if you have one.

How far can this go? In theoretical physics, people often discuss reducing all of physics to a single theory, maybe something you could fit on a t-shirt. But why must the universe on a t-shirt be represented by an equation? With such a theory in hand, could there be a simple representation of an elegant observation that, in context, encapsulates the nature of the universe?

  1. Bill    3663 days ago    #

    I’ll nominate Franklin’s Photo 51, which was the crucial piece of data in elucidating the structure of DNA.

    There’s a bigger image here for those nerds who, like me, want to print it on a t-shirt one day.

    (Why you gotta use Textile? Why not lemme use html?)

  2. sam    3663 days ago    #

    this is a really cool topic. i wish i could think of a good example. instead, i’m looking forward to others listing some!

  3. fishcake    3662 days ago    #

    good call, Bill! “The instant I saw the picture my mouth fell open and my pulse began to race…. the black cross of reflections which dominated the picture could arise only from a helical structure… mere inspection of the X-ray picture gave several of the vital helical parameters.” -Watson

  4. agar-agar    3661 days ago    #

    I would have to nominate Jacob and Monod, who, with toothpick firmly in hand and carbon source jelly-like on plate, teased apart the workings of the lac operon. No one-shot picture here though, it probably took a bunch of plates and mutants…

  5. Fred Ross    3660 days ago    #

    There is the Mezelsohn (sp?) and Stahl paper on DNA inheritance which is almost exactly what you describe, but I think the most impressive one is the cosmic microwave background power spectrum. The amount of physics discernible from that plot is absolutely astounding.

  6. Rosie Redfield    3659 days ago    #

    Here’s a URL to the original Meselson-Stahl image:,6452,498974-,00.html

  7. Andre    3657 days ago    #

    Bill, I like that. I was initially thinking that x-ray diffraction patterns
    often lead to new insights but don’t do so well on the “simple representation”
    side of things since a lot of analysis is often needed to get detailed
    structural information. But, in light of fishcake’s quotation from Watson,
    I’ve changed my mind about that. Good stuff.

    Fred, also a good choice. For those not familiar with it, here is a plot of the CMB “angular spectrum”:

    and here’s a discussion of one way it impacts cosmology by Sean from Cosmic Variance:

    Rosie, thanks for the link!

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