Theories, processes, solutions, etc. named for 2 people

In My Humble Opinion
1

…with a general description to prevent people from having to google it.

Modigliani-Miller theorem - the basis for corporate financial structure management; shows that, under perfect conditions, a company’s value is not affected by how it’s financed

Black-Scholes model - a mathematical model used to determine the value of a financial derivative

Bornhuetter-Ferguson technique - a method of forecasting insurance losses by actuaries

Duckworth-Lewis method - a calculation used in cricket to determine the winner of a shortened match

2

The Dunning / Kruger Effect

The Teller / Ulam Design

The Schmidt / Cassegrain telescope

3

The ones happen to spring to my mind right away are:

The Schartz-Metterklume Method - a method to make children understand history by acting it out themselves (fictitious, from the short story of that name by Saki)

Navier-Stokes equations - equations in physics that describe the motion of viscous fluid substances

Calabi–Yau manifold - a type of topological structure used in theoretical physics

Gauss-Jordan elimination - a method of using matrices to solve linear systems of equations

4

The Hall–Héroult process for smelting Aluminum. Independently invented by 22 year-olds.

Richard Feynman is a well-hyphenated person. Some examples:

Feynman–Kac formula
Feynman–Stueckelberg interpretation
Hellmann–Feynman theorem
Bethe–Feynman formula

5

Maybe this is cheating, but there are a few lists on Wikipedia that give dozens of answers:

gives: Beer–Lambert law, Biot–Savart law, Cauchy–Riemann equations, Cayley–Hamilton theorem, Church–Turing thesis, Law of Charles and Gay-Lussac, Curie–Weiss law, De Bruijn–Erdős theorem, Erdős–Anning theorem, Erdős–Beck theorem, Erdős–Gallai theorem, Erdős–Kac theorem, Erdős–Nagy theorem, ok I’m getting tired of Erdős, but there’s a lot more.

Then this one gives more: List of scientific equations named after people - Wikipedia
Adams–Williamson equation, Allen–Cahn equation, Ashkin–Teller model, Batchelor–Chandrasekhar equation, Benjamin–Ono equation, Birch–Murnaghan equation of state, Birkhoff–Rott equation, Blaney–Criddle equation, Borda–Carnot equation, Buckley–Leverett equation, Cahn–Hilliard equation, Callan–Symanzik equation, Callendar–Van Dusen equation, … I didn’t even get through the C’s on that page.

And then there’s List of scientific constants named after people - Wikipedia which gives a few: Copeland–Erdős constant, Embree–Trefethen constant, Erdős–Borwein constant, Euler–Mascheroni constant, Landau–Ramanujan constant, Meissel–Mertens constant, Ramanujan–Soldner constant, Sackur–Tetrode constant, Stefan–Boltzmann constant. I think I got all of them from that page.

And then there’s this page, List of equations - Wikipedia which overlaps a lot with the others, but probably has some new ones.

None of them seem to mention my favorite, the Banach-Tarski paradox.

6

Newton-Raphson iterations; Diels-Adler reactions…

7

The Michelson–Morley experiment disproved the existence of cosmic ether and was an important stepping stone towards Einstein’s work on relativity.

8

Born-Oppenheiemer

9

I was curious about Duckworth-Lewis and so looked it up and discovered that it is now called Duckworth-Lewis-Stern. Disqualified!

10

No, since it was called that one one time. In fact, Black-Scholes is now often called Black-Scholes-Merton.

11

In quantum mechanics, Bose-Einstein statistics describe the behavior of one sort of particles (called “bosons”), and Fermi-Dirac statistics describe the behavior of the other sort (called “fermions”).

And it’s not surprising that Erdös shows up a lot in these lists: He’s most famous for having collaborated with nearly everyone; the Kevin Bacon of academia.

12

I was joking, although it wasn’t obvious. I assumed someone who knew enough about cricket to know about D-L would also know the most updated version of the name.

13

I’ve always liked the Smoot-Hawley Tariff myself. That and the Mason-Dixon Line.

14

There’s even an Erdős number for mathematicians, similar to the Bacon number for actors.

Ultra-nitpick since you went to the trouble of adding an umlaut to his name – his name actually uses a double acute accent, not an umlaut/diaeresis. It’s used mainly in Hungarian, which has FOUR versions of the letter O, distinguished by different diacritics.

15

Einstein-Rosen bridge.

16

The Birkeland-Eyde process was used to start Norwegian production of Nitrogen fertilizer.

17

Just came across another Feynman law:

Wheeler–Feynman absorber theory

Itself based on the Abraham–Lorentz force and inspired the Hoyle–Narlikar theory of gravity. (The latter of which is stead-state hokum, of course.)

Which brings up the question of what’s the longest connected chain of such pairs?

18

Bachman-Turner Overdrive. Do I have to provide a definition?

More in the spirit of the OP, The Hatch-Waxman Act (AKA The Drug Price Competition and Patent Term Restoration Act) defined the ANDA approval pathway for generic drugs in the US.

j

19

The Baader-Meinhof phenomenon.

20

The Denavit-Hartenberg matrix, useful in robotic kinematics. I actually new Professor Hartenberg at Northwestern when I was a grad student and he was a very old, very smart man.