Nature’s oxymorons: Black holes made of light and how to find them

  • Date: 03 OCTOBER 2025  from 17:30 to 19:00

  • Event location: Sala Rossa, Palazzo Marchesini, Via Marsala 26 - Bologna.

  • Type: Lectures

Speaker

ISA Visiting Fellow -Ravi K. Sheth

Professor  University of Pennsylvania, USA

 

Visit Prof Sheth's website

Galileo showed how things fall, and Newton explained why. In Newton’s theory of gravity, sufficiently concentrated matter will create a ‘black hole’ - an object from which light cannot escape. More than two hundred years later, Einstein showed that matter was just a concentrated form of energy, and that sufficiently concentrated energy will create a black hole. Since light is a form of energy, Hawking and others argued that it should be possible to make a black hole from light - a sort of natural oxymoron. I’ll discuss why such light black holes might actually be quite heavy, and might make up most of the matter in our universe. Finally, I discuss how we might detect them even though they don’t shine.