neutrinos

[Ezekiel.]

How many are there in a cubic in inch?

[chroot]

The number density of each neutrino species is theorized to be about 56 per cubic centimeter, for a total number density of around 150 neutrinos per cubic centimeter.

That's about 2500 per cubic inch.

- Warren

[Ezekiel.]

where did you get that information, if you don't mind my asking

[chroot]

Simpson, John J., The Sudbury Neutrino Observatory, AAPT Summer Meeting, AAPT Announcer 30, 71, Summer 2000

- Warren