Why Science says your Lovelife Sucks: 285,000 to 1

Can science be used to answer the existential quandaries that haunt us? Questions like why your love life sucks?

Yes, it can!

The Drake Equation was used by Carl Sagan to calculate the chances of highly evolved alien life existing in our galaxy.

A physicist named Peter Backus applied the Drake Equation to a more pressing issue; his own statistical chance of finding a girlfriend.

Read the paper here: Why I don’t have a girlfriend.

The results were not encouraging.

After some mathematical gymnastics, Backus concluded, “There  are  26  women  in the  UK with  whom  I  might  have  a  wonderful  relationship.   So,  on  a  given  night out in  London  there  is  a  0.000 34%  chance  of  meeting  one of  these  special  people,  about  100  times  better  than finding  an  alien  civilization  we  can  communicate  with. That’s  a  1  in  285,000  chance.  Not  great.”

That’s right. It turns out, you have about 100 times greater chance of finding a partner than finding intelligent alien life in our galaxy!

In an episode of This American life, Ira Glass and David Kestenbaum break down the numbers for the city of Boston.

You will never look at your lovelife the same again.

 

Ira Glass

OK. So a couple of physicists walk into a bar. Just kidding. They’re not at a bar. They’re at a school. Scientists in training.

David Kestenbaum

I’m sure this story seems strange to you, but to me, it was just like another day in the physics world.

Ira Glass

David Kestenbaum used to live in the physics world. These days he lives in our world. You can hear him in our world as part of NPR’s PlanetMoney team reporting on economics. But at the time in this story he was getting a PhD in high energy particle physics at– there’s no way to avoid the name-droppyness of what I’m about to say– at Harvard University. But to paraphrase UsMagazine, Harvard physicists, in certain ways around the office, they’re just like us.

David Kestenbaum

There’s always a time of day when someone made a pot of very strong coffee and afterwards everyone drank the coffee and then didn’t quite want to work yet. And so we all stood around and talked about various things. And there was a blackboard or a white board or something there. And we were talking about how nobody really had girlfriends.

Ira Glass

So this being physics world, the next logical thing to do was to employ the power of mathematics to estimate the likelihood of finding a girlfriend. And so they start jotting down a calculation.

David Kestenbaum

I guess it’s sort of a variation on– you know this thing called the Drake equation?

Ira Glass

No.

David Kestenbaum

That is a way to estimate how many planets are out there that have intelligent life on them.

Ira Glass

OK, so in this Drake equation, apparently you start with how many stars are in the universe. That is, all the places where there might be life. And then you subtract out all the stars that don’t have planets around them, right? Because there can’t be life there. And then you subtract out all the planets that are too far from the sun or too close to the sun to support life and so on and so on– you get the idea– until finally you come up with the likelihood of a planet with life evolved to the point of intelligence. OK. They run the same kind of math now, except– and I realize this is going to sound a little strange when I say this– they replaced intelligent life with girlfriends.

David Kestenbaum

So we started to do the calculation on the board and– can you look up what the population of Boston is?

Ira Glass

Now David is asking me to look this up because at this point in our interview I actually made him run the math for me with real numbers that we got from the internet. So he started with the population of Boston, because he and his fellow physics students wanted girlfriends in Boston, where they all lived. Population of Boston, I found online, was a little under 600,000.

David Kestenbaum

So you start with 600,000. Which sounds great, except that half of them are guys, right? And I’m only interested in girls.

Ira Glass

OK, so that’s 300,000.

David Kestenbaum

And then I want people, let’s be honest, probably within 10 years of my age or something. Right?

Ira Glass

OK, so 10 years on either side. So that means–

David Kestenbaum

I’m actually looking at some numbers here. It looks like if you go from 20 to 40, you’re talking– that’s still, like, 35% of the population, 1/3 or something.

Ira Glass

So that means that out of 300,000 women, that leaves 100,000 in his age range. These being doctoral students, they wanted girlfriends who were college grads. Well, OK. About 25% of Americans over 25 years old have graduated from college. That knocks out roughly 3/4 of these women.

David Kestenbaum

Ouch.

Ira Glass

So you’re down to– we were at 100,000. So you’re down to 25,000.

David Kestenbaum

Then you start applying stuff like how often are they single.

Ira Glass

Yeah. Let’s say half of them are single. So now you’re down to 12,500.

David Kestenbaum

Yeah. See, it’s getting scary now, right?

Ira Glass

And then, of course, you get to how many people are actually attractive to you. And even if you give a really high percentage like one in five, that knocks your pool of candidates down from 12,500 to 2,500.

David Kestenbaum

Ugh. In the whole city of Boston, right?

Ira Glass

Yeah.

David Kestenbaum

That’s just like a needle in a haystack.

Ira Glass

And that 2,500 is before you get to anything personal like your religion or how you see the world, what’s your sense of humor. So Dave and his fellow students are talking about this, these rather kind of depressing numbers. And one of their professors comes in.

David Kestenbaum

She’s not married either. And so we start to draw it for her. And then we started to say, well, OK, half of them are men. So we’d circle half. And then we’d say, well, what’s the age group you’re interested in? And then we’d sort of circle a smaller subset. And then she had all these other requirements like the guy had to be taller than her. And she’s pretty tall. So that really limited things. And then she said he had to be smarter than her. And she’s a Harvard physics professor, so that was even smaller. And basically we got down to there being nobody.

[LAUGHTER]

David Kestenbaum

She’s alone.

Ira Glass

During this period of your life when you would think about these numbers, were you sure the entire time that there was somebody out there?

David Kestenbaum

Yeah. I don’t know why. But at the beginning of every mathematical proof people often write, assume that there exists x. [LAUGHS]. Assume we have an infinite surface bound by something or whatever.

Ira Glass

Right.

David Kestenbaum

It’s like assume there exists some girlfriend. There’s totally that act of faith underneath it, yeah. But I had a more scientific view, which is that there are people out there who might be right for me, not just one person. That seemed like in a silly novel or something, you know?

Ira Glass

Yeah.

David Kestenbaum

I don’t believe there’s just one. If there were just one person out there, good luck. They could speak Chinese. They probably do, right? What are the odds you’re going to find them and the translator? You gotta believe there’s more than one person.

© 2013 Chicago Public Media & Ira Glass