Learn about universe's missing mass

The Fermilab Lecture Series presents "In Search of Our Universe's Missing Mass and Energy," by Fermilab scientist Dan Hooper, at 8 p.m. Friday.

The 20th century was astonishing in all regards, shaking the foundations of practically every aspect of human life and thought -- physics not least of all.

Beginning with the publication of Albert Einstein's theory of relativity, through the wild revolution of quantum mechanics, and up until the physics of the modern day (including the astonishing revelation in 1998 that the universe is not only expanding, but doing so at an ever-quickening pace), much of what physicists have seen in our universe suggests that a large proportion of the universe is unseen -- that we live in a dark cosmos.

Everyone knows that there are things no one can see -- the air you're breathing, for example, or, to be more exotic, a black hole. But what everyone does not know is that what you can see -- a book, a cat, or the planet -- makes up only 5 percent of the universe. The rest -- 95 percent -- is invisible. Its presence is discernible only by the weak effects it has on visible matter around it.

This invisible stuff comes in two varieties -- dark matter and dark energy. One holds the universe together, while the other tears it apart. What these forces really are has been a mystery for as long as anyone has suspected they were there, but the latest discoveries of experimental physics have brought some insight.

Learn more about the universe's missing mass and energy on Friday as Dan Hooper speaks on this topic.

Hooper is a fellow in the theoretical astrophysics group at Fermilab. His research investigates dark matter, supersymmetry, neutrinos, extra dimensions and cosmic rays. He received his doctorate at the University of Wisconsin in 2003, and afterward was a postdoctoral fellow at the University of Oxford in England. His first book, "Dark Cosmos," was published by Smithsonian/Harper Collins in 2006.

Admission to "In Search of Our Universe's Missing Mass and Energy" is $5. Tickets are non-refundable. For information or telephone reservations, call (630) 840-ARTS (2787) weekdays between 9 a.m. and 4 p.m. Phone reservations are held for five working days, but will be released for sale if not paid for within that time.

On the evening of the event, the box office opens at 7 p.m. and will-call tickets can be picked up, or available tickets purchased, at that time.

At this time, both the Pine Street entrance from Kirk Road in Batavia and the Batavia Road entrance west of Route 59 in Warrenville are open.

For details, visit www.fnal.gov./culture.