Why is the night sky dark? Why is space dark? One of the most interresting problems in cosmology is Olber's paradox, which states that the sky should be infinitely bright day and night. Clearly this is not true. Usualy this paradox, attributed to an astronomer Heinrich Olber, is solved by stating the universe is finite, not eternal, or etc. However, a more conventional solution exists as well. It doesn't require resorting to such exotic statements. Radiation from far away stars and matter is shielded by closer by stars and matter. Wanna know more? Then read this article.
Unfortunately no such solution is possible for the similar Gravity paradox. Which states through a similar deduction that any object has een infinite gravitional potential energy at any point in space. Less visible but just as weird as Olber's paradox. Since gravity can not be shielded, another explanion is needed for this paradox. There is one, which is also described in the article, but it is less convenient and also a bit odd. Maybe, this odd infinite gravitational potential has something to do with Mach's principle?
Belorussian translation (by Bohdan Zograf)
Russian translation (by Mark Pozner), courtesy of All Science Magazine
Polish translation (by Olga Babenko)
Macedonian translation (by Zoran Mitreski)
Ukrainian translation (by Sandi Wolfe)
Spanish translation (by Laura Mancini)
French translation (by Lauro Beoschat)
Uzbek translation (by Sherali Niyazova)
Lithuanian translation (courtesy of Giedrius Sadauskas)
Catalan translation (courtesy of Claudia Monteys)
Albanian translation (courtesy of Altin Bici)