Transcription
A lot of people are familiar with Einstein's famous equation E = mc squared, which says that energy is equal to mass times the speed of light squared. And what that really means is that in any amount of mass, so if I think about the mass of my little finger, there's a tremendous amount of energy. So if I could convert my little finger into pure energy, the nuclear bombs that were dropped on Japan, you know, converted on the order of like a dime's worth of mass. So you know, there would be many, many, you know, nuclear warheads right in my little finger's worth of energy.
But E = mc squared also goes the other way. If you have a lot of energy, that basically starts acting the same way as mass. And it does so in something called virtual particles. If you have a lot of energy in a small space, the universe will start to actually create particles that have the same energy in their mass. So a lot of energy can actually become mass. And this is how our particle accelerators work. This is why you can discover new particles. Because if you just have a very energetic collision, like you take two gold nuclei and you slam them together, there's so much energy produced in that collision that it starts to pop off particles just from the amount of energy. And as long as you have enough energy, you can make any particle the universe has. The particles come off in all different flavors as long as they have the same amount of energy that that collision is putting out.
So neutron stars are doing something kind of like that. They're actually becoming sort of natural particle accelerators in a way just because of their mass. There is so much gravitational contraction that the magnetic field, the electric field and magnetic field of that star is actually compressed around this tiny little object now. So neutron stars have magnetic fields that are trillions of times more strong than a typical magnet you might have in your home, like your refrigerator magnet. It would actually pull regular matter apart, just the magnetic field. But there's so much energy in those magnetic fields.
So think about E = mc squared. There's so much magnetic energy right around a neutron star that the vacuum of space itself starts to make these virtual particles. And I was at a lecture one time and this just blew my mind. You know, this is what happens when you work at NASA and you know, you go into a lecture your colleagues are having, you know, just any day of the week. And they were saying that right around a neutron star the density of space itself, the vacuum of space, right a place where it's a vacuum, there aren't any particles otherwise has about three times the density of pure iron. Just from that amount of virtual particles being produced by the energy of that magnetic field.
So, what's it like to fly around something where space itself has the density of three times of iron? What's that like? What does that look like? [laughter] I would love to see what a neutron star looks like from a safe distance and I'm not exactly sure what that is. When you're dealing with so much energy that even empty space becomes much more dense than iron.