Quanta Magazine Season 2015, Episode 10: Alan Guth: How Many Two-Headed Cows in a Multiverse?

1

What Happens if You Fall Into a Black Hole?

David Kaplan explores one of the biggest mysteries in physics: the apparent contradiction between general relativity and quantum mechanics.

2

Freeman Dyson: A ‘Rebel’ Without a Ph.D.

A wide-ranging interview with the legendary mathematical physicist Freeman Dyson in which he discusses his work with Richard Feynman, his attempts to build a spaceship propelled by nuclear bombs and his controversial views on climate change.

3

Artur Avila: A Brazilian Wunderkind Who Calms Chaos

A video profile of the mathematician Artur Avila, whose solutions to ubiquitous problems in chaos theory have earned him Brazil’s first Fields Medal in 2014.

4

Manjul Bhargava: The Musical, Magical Number Theorist

A video profile of the 2014 Fields medalist Manjul Bhargava, whose search for artistic truth and beauty has led to some of the most profound recent discoveries in number theory.

5

Where Did the Universe Come From?

Where did the universe come from? David Kaplan explores the leading cosmological explanation with the help of a baking metaphor.

6

Yitang Zhang: An Unlikely Math Star Rises

The opening scene from George Csicsery’s film "Counting From Infinity," about Yitang Zhang, a previously unknown mathematician who two years ago solved a major problem in number theory that catapulted him to mathematical stardom.

7

Martin Hairer: In Noisy Equations, One Who Heard Music

A video profile of the 2014 Fields medalist Martin Hairer, whose epic masterpiece in stochastic analysis, experts say, “created a whole world.”

8

Maryam Mirzakhani: A Tenacious Explorer of Abstract Surfaces

A video profile of the 2014 Fields medalist Maryam Mirzakhani, whose monumental work draws deep connections between topology, geometry and dynamical systems.

9

Subhash Khot: A Grand Vision for the Impossible

A video profile of the 2014 Nevanlinna Prize winner Subhash Khot, whose bold conjecture is helping mathematicians explore the precise limits of computation.

10

Alan Guth: How Many Two-Headed Cows in a Multiverse?

In an infinitely branching multiverse, says MIT cosmologist Alan Guth, “there are an infinite number of one-headed cows and an infinite number of two-headed cows. What happens to the ratio?”

11

Hiranya Peiris: How to Test If We Live in a Multiverse

University College London physicist Hiranya Peiris explains the seemingly impossible -- how the multiverse can be experimentally tested.

12

How Did Life Begin on Earth?

In this 2-minute video, David Kaplan explores the leading theories for the origin of life on our planet.

13

Fly-Vac: Groundhog Day for Fruit Flies

Benjamin de Bivort’s lab at Harvard University developed a device called the fly-vac to study individual behavior. Upon entering a chamber, the fly must choose to walk toward the light or dark end. A vacuum then sucks it back to the starting point, and it makes the choice again.

14

Why Do Flies Walk This Way?

In a device in Benjamin de Bivort’s lab at Harvard University, a fly wanders through a tiny Y-shaped maze, choosing at the Y’s vertex whether to walk left or right. This array of Y-mazes allows researchers to track individual behavior in many flies simultaneously.

15

How Symmetry Shapes Nature’s Laws

In this 2-minute video, David Kaplan explains how the search for hidden symmetries leads to discoveries like the Higgs boson.

16

James Bullock: The Case for Complex Dark Matter

James Bullock, a physicist at the University of California, Irvine, explains why dark matter might be more complicated than astronomers have assumed.

17

Nancy Moran: An Explorer of Life’s Deepest Partnerships

Nancy Moran, a biologist at the University of Texas at Austin, explains how colony collapse disorder led her to study the bacteria that live in the guts of bees.

18

Nima Arkani-Hamed's Visions of Future Physics

Nima Arkani-Hamed, a physicist at the Institute for Advanced Study, makes his "big-picture" case for building a 100-TeV particle collider.

19

What Is a Species?

David Kaplan explains why a simple definition of 'species' is hard to come by in our fifth In Theory video.

20

Gabriela González: Searching the Sky for the Wobbles of Gravity

Gabriela González explains how to measure black-hole collisions using gravitational waves.

21

Joan Strassmann: The Woman Who Stared at Wasps

Joan Strassmann explains the benefits of studying social amoebas.

22

Christoph Adami: The Information Theory of Life

Christoph Adami explains how information theory can explain the persistence of life.

23

Richard Dawid: Why Trust a Theory?

Richard Dawid discusses the fine line between science and speculation.