The Rest Is Science – "Unadulterated Dice Nerding"

Date: January 1, 2026
Hosts: Professor Hannah Fry & Michael Stevens (Vsauce)

Episode Overview

In this lively "Field Notes" edition of The Rest Is Science, mathematician Hannah Fry and science creator Michael Stevens gleefully dive into the peculiar world of dice, randomness, crowd dynamics, and the quirky intersection between mathematics and everyday life. Starting with a listener mailbag, they muse about "maths" vs "math," analyze mosh pit fluid dynamics, and then embrace a full-on nerd-out over unconventional dice, randomness, and mathematical oddities—complete with physical show-and-tell. Whether you love tabletop gaming, puzzles, or the joy of a well-rolled die, this episode is a celebration of all things nerdy and mathematical.

Key Discussion Points & Insights

1. The Field Notes Format & Opening Banter (01:21–02:19)

• The hosts clarify the dual format of their podcast: main episodes vs. lighter, show-and-tell "Field Notes" episodes.
  • "I still feel like we put so much more effort into the main ones… These ones, we just have a load of fun." — Hannah (01:57)
• Establish the relaxed, exploratory tone.

2. Mailbag: "Math" vs. "Maths" (02:22–05:06)

• Listener question: Is it "math" or "maths"?
• Michael describes his American background, only learning about "maths" after moving to the UK.
  • "You guys across the Atlantic call it maths… I didn’t even know that until I moved to the UK." — Michael (02:33)
• Hannah appreciates both forms, patriotically using "maths" but admits "math" might make more sense.
• Language as a flexible tool: "We all know what we’re talking about, and that is the point of language.” — Michael (05:02)

3. Mosh Pits, Fluid Dynamics & Crowd Safety (05:07–13:48)

Summary of the Scientific Paper:

• Academic study analyzed mosh pits and circle pits at heavy metal concerts.
  • "If you stop thinking of people as people and you start thinking of them as particles… actually, what you see in mosh pits is this behavior that is common across systems of fluids." — Hannah (06:19)
• Two crowd behaviors:
  1. Flocking (copying neighbors—like starlings or fish)
  2. Random, local movement (individual impulses)
• Mosh pits behave like a gas (Maxwell-Boltzmann distribution), while circle pits form vortex patterns akin to fluids.

Emergence & Danger in Dense Crowds:

• At ~5-6 people per m², crowd movement shifts from fluid-like to "granular flow" (like sand), increasing danger.
  • "When it stops flowing like a fluid and instead becomes... granular flow. It's much more like sand in a sort of collapsing..." — Hannah (09:32)
• Crowd crushes stem from these physics; individuals lose autonomy.
• Safety insight: Placing a bollard before a crowded exit reduces clogging and enables smoother flow (counterintuitive fix).
  • "If you put a bollard immediately in front of the doorway… you get much, much smoother flow of people." — Hannah (12:52)
• Modern stadiums use offset railings/barriers for crowd management.

Personal Experience:

• Michael recalls being swept in a dense crowd in Times Square—not by pushing, but emergent collective motion.
  • "I was like being lifted and moved like this, like I was in an ocean. And I was like, this is… very scary." — Michael (10:51)

4. Dice Nerding: Odd-Shaped Dice & Randomness (13:49–32:17)

Show-and-Tell Segment:

Michael brings a D1 (one-sided die), up to a D10, and demonstrates the logic and engineering behind unusual dice.

The D1, D2, and Beyond:

• D1: Looks like penne pasta, always lands "one"—for when you can't make a choice but want to pretend.
  • "If it rolls a one, I'll do it. It's always gonna be one." — Michael (15:23)
• D2: Essentially a coin.
• D3-D10: Discussion of shapes, fairness testing (extensive 3D-printing and physical dos testing), and odds.
  • "We 3D printed all of the prototypes… and found that they were all fair right off the bat." — Michael (18:19)
• Barrel dice for odd numbers (e.g., D5, D7, D9) require careful engineering for fairness and are a talking point for enthusiasts.

Cultural Connections:

• Neither host is a die-hard Dungeons & Dragons player.
• Everyday use: Dice can replace decision-making (e.g., paying restaurant bills or making day-to-day choices).
  • "I'm extremely in favour of switching over all your decision making to dice rolling rather than actually making any choices." — Hannah (20:53)

Anecdotes:

• Dishoom Restaurant in the UK used dice for promotions: guests could roll a die, and a six meant a free meal. Statistically identical to a 15% discount, but, as Hannah explains: "How much more fun is it to do it where it's based on the roll of a die?" (21:47)
• Michael describes die "cheating": heating dice makes one side heavier, subtly biasing rolls (23:00–23:23).

The Quest for Minimalist Fairness:

• Hannah introduces the "wonky die"—a deformed cube with just the minimal symmetry for fairness.
  • "This is like exactly right. This looks like a normal die, but it looks like someone sat on it…" — Hannah (24:37)
  • "It has the minimum amount of symmetry required to make the dice fair and no more." — Hannah (25:19)
• Both hosts marvel at the balance of fairness and aesthetics in die design.

5. True Randomness: When Dice Aren't Enough (26:27–29:55)

Hannah’s Small Book of Random Numbers:

• A physical book filled solely with hundreds of pages of random digits, a nod to early statistical, cryptographic, and military needs for unbiased randomness.
  • "One of the reviews... said that it relies too heavily on 10 characters, which I quite enjoyed." — Hannah (27:19)
• The importance of true randomness, versus pseudo-random algorithmic (computer-generated) numbers.
• Physical randomness sourced from natural processes: static, lava lamps, radioactive decay.

Michael’s Counter: Non-Random Numbers

• Shows off his "One Million Digits of PI" book and, humorously, "The Square Root of Four to a Million Places" (i.e., "2" followed by a million zeros).
  • "It also begins in the way that we would all expect… 2.0… and then it's just a million zeros." — Michael (31:00)
• Touching on the playful wastefulness and educational value of producing such a book.
  • "That tree died with honor." — Michael (31:44)

Fun Fact:

• Reference to Brady Haron and Matt Parker, who rolled out a million digits of PI on airport runway for a YouTube video—later sold as memorabilia for a nice watch.

Notable Quotes & Memorable Moments

• “If you stop thinking of people as people and you start thinking of them as particles… what you see in mosh pits is behavior common across systems of fluids.” — Hannah Fry (06:19)
• “I was like being lifted and moved like this, like I was in an ocean. And I was like, this is… very scary.” — Michael Stevens (10:51)
• “If you put a bollard immediately in front of the doorway… you get much, much smoother flow of people.” — Hannah Fry (12:52)
• “I'm extremely in favour of switching over all your decision making to dice rolling rather than actually making any choices.” — Hannah Fry (20:53)
• “This is like exactly right. This looks like a normal die, but it looks like someone sat on it… It has the minimum amount of symmetry required to make the dice fair and no more.” — Hannah Fry (24:37–25:19)
• “That tree died with honor.” — Michael Stevens, upon justifying printing a book of one million zeros (31:44)
• “Some people call it people repellent. I call it a friend finder.” — Michael Stevens, on using odd dice in public (26:20)

Timestamps for Important Segments

• 01:21–02:19: Introduction to "Field Notes"
• 02:22–05:06: Math vs. Maths discussion
• 05:07–13:48: Mosh pits, crowd physics, and safety
• 13:49–26:27: Dice philosophy and engineering, show-and-tell with Michael’s dice
• 20:53–22:21: Dishoom dice promotion & the psychology of chance-based rewards
• 23:00–23:23: Michael explains how to subtly bias a die
• 24:37–25:19: Hannah explains the wonky, minimal-symmetry die
• 26:27–29:55: Books of random numbers and mathematical oddities
• 31:44: Michael’s “the tree died with honor” remark

Tone & Style

Conversational, self-deprecating, and joyously nerdy. Both hosts weave scientific rigor with humor and curiosity, often poking fun at themselves and one another, while maintaining a sense of genuine wonder about mathematical and physical phenomena in the everyday.

Conclusion

The episode exuberantly celebrates dice, randomness, and crowd physics while illustrating how scientific thinking transforms our understanding of even the most mundane aspects of daily life. With charm, wit, and plenty of personal anecdotes, Hannah and Michael leave listeners eager to roll the dice on their own intellectual adventures—and maybe even on who pays for dinner tonight.