Talk:Louis Slotin

Criticality experiment specifics

This may not be the right place but what I'm wondering about is what specifically the early criticality experiments sought to find out.

In a "normal" quantitative science experiment, what you do is keep all parameters constant except one, which you vary in order to obtain different results. These results then make it possible to arrive at formulas or algorithms to describe the interrelations between the different parameters.

For example, a simple experiment about the electrical conductivity of liquid solutions would be to dip two electrodes into a sample solution, apply a current and measure the voltage. In a series of experiments you could then vary the distance between the electrodes, or the concentration of the solution, or the current, or the voltage etc, and even do multiple series for different electrolytes to compare those to each other, and arrive at the specific conductivity of given electrolytes.

Now it is clear that in the criticality experiments, they measured neutron flux. But the variable parameter in the Slotin experiment seems to be "the shape of the slot between the two hemispheres" but there doesn't even appear to be any measurement of some distance that would allow you to calculate that geometry. Cancun (talk) 12:12, 23 November 2021 (UTC)

The value of a critical mass of plutonium is difficult to sense. Not only does it hinge on the temperature of environment and other physical factors, but on the surrounding materials. The two hemispheres and the ring were designed to be "about 75% critical" when assembled. Placing them within the tamper would raise that to about 95%, but the question was, how close? They wanted to get it as close as possible so that the explosive shock, when it came, would drive the core as high into the prompt-critical range as could be arranged for before firing. Notice that both accidents involved building artificial tampers around the core.

Apparently, there is a considerable difference between having the beryllium almost all the way down, and all the way down. I'm not really clear why that is the case; it implies that the beryllium shell was carefully calibrated by previous testing to achieve just a tad better reflective results than the uranium tamper in the real bomb, so they could see how close they could push it, with the dangerous potential of pushing it too far. Unlike Fermi's control rods in the CP1 that he could move fractions of an inch and then wait 15 minutes to see how the curve formed up, they didn't have the patience for careful experimentation at this point. They developed a method and never looked back at it. SkoreKeep (talk) 06:40, 24 November 2021 (UTC)

Mention of Short Film

A while ago I removed a mention of a student film covering Louis Slotin and cited WP:Notability for the removal reason; I see I was incorrect to do so as the other editor pointed out in the revision, but I have removed it again and want to elaborate why. There is only one linked source, which is just a link to a synopsis about the film and a listed award that was give by the university. I could find no other sources reporting on it, including it and the name of the director in the article feels to me like self-promotion of an otherwise non-noteworthy film. I don't think it belongs, but I invite anyone wishing to undo my revision again to respond below so I can better understand where my reasoning is wrong (if I'm wrong). Equirax (talk) 03:01, 8 January 2026 (UTC)

• I cannot see how mention of this nonnotable film by a student filmmaker helps our readers. EEng 17:11, 8 January 2026 (UTC)

I agree with EEng; sorry I reverted you, I didn't look closely at the source, I just read your edit summary. ---Avatar317^(talk) 02:57, 9 January 2026 (UTC)

no worries! Equirax (talk) 05:42, 9 January 2026 (UTC)