Two weeks ago, we had hail here in Stockholm. At that time I was homewards bound on the highway, and that's where I would be staying for half an hour while rescue crew scratched a motorbike off the middle lane. On the radio run "Heartbreaker" by Dionne Warwick. It's one of these songs I've heard a million times but never listened to, girl in love, guy who doesn't call, same old story. "Why do you have to be a heartbreaker, When I was bein' what you want me to be?" I probably wouldn't call her either. There's Swedish "nyheter" on the other frequencies, but I already knew the weather was sucking greatly, the highway was clogged, and the rest I wouldn't understand anyway, that being the state of my Swedish. Hail drumming on the car roof, Dionne sang "My love is stronger than the universe," and the physicist in me couldn't avoid asking WTF is that supposed to mean? (It's not a four letter word. No, it isn't.)
Okay, so the universe is supposed to have a strength. It springs to mind the gravitational force exerted by all the mass in the universe. Since you can't place yourself outside the universe (probably where Dionne's guy sits) the question is what's the force acting on you while inside, caused by the expansion of the universe? Well, we know that bound systems up to galactic scales don't take part in the expansion, but let's forget that for a moment and pretend the universe would try to rip lovers apart on planetary surfaces. If Dionne's non-caller was as far away from her as he could possibly get on Earth, ie 10,000 km or so, the force comes to 10-26N. Not very impressive. The laws of attraction might get you into trouble, but actually gravity is even weaker than the weak force.
No, we have to think about this differently. We should be asking what's the strength of the structure of the universe? So, as everybody knows, the universe is made of strings, and a string has a tension which is something like the square of the Planckmass, take or give some orders of magnitude. Putting all dimensionful units back in, that comes out to be about 1044N. We could compare this to the force acting on Dionne on the surface of a neutron star, which is a measly 1014N. Yes, clearly, there's string theory on the radio. Though I suspect you'd get pretty much the same answer asking what it takes to break a link in a fundamental spin network.
Passing by the accident zone I contemplate the lack of friction and the forces at work. The radio plays Tori Amos, Little Earthquakes. It doesn't take much to rip us into pieces.