In the more than three decades since researchers started seeing the first signs of AIDS, millions have lost their lives hoping modern medicine might produce a cure in time. While a cure still eludes the brightest minds, treatment for people who have AIDS (acquired immune deficiency syndrome) has come a long way. For instance, someone who suspects they are at risk today can take a daily pill, Truvala, also known as PrEP, that proactively minimizes the likelihood he will contract HIV, the virus that causes AIDS. Projects to reduce the spread of AIDS in the United States and Africa have made excellent headway thanks to a collaboration between international organizations led by the U.S. government, the United Nations, the World Health Organization, and partners around the world.

Physicist Brian Greene joined Stephen Colbert on “The Late Show” to walk Stephen through the finer points of one of science’s most influential theories with a water bottle and several fists full of marbles. Greene arrived by ‘science mobile’ to offer a brief lesson on the questions Einstein was attempting to answer when he conceived of special relativity and, ten years later, general relativity. The general theory of relativity turns 100 years old this month. But to fully understand Einstein’s ideas, you need to see them in action.

In 1998, Adam Riess and his colleagues discovered dark energy. It was Nobel Prize-winning work that shocked the physics world. In order to understand what dark energy is, why it’s important, and why World Science U’s Master Class hosted by Adam Riess is the logical next step, we have to take a brief look at the work Einstein was doing nearly a century earlier. Back in 1917, Einstein introduced what he called the cosmological constant. He needed a way to account for a repulsive force (a push) that would cancel out the force of gravity (a pull). Those two opposing forces, working against each other, would explain the static universe Einstein thought we lived in. History tells us he thought wrong. (Einstein owned up to it later in life, calling it his ‘greatest blunder.’)

Wednesday, November 25th is a big day for fans of scientific breakthroughs that re-shape our understanding of how the universe operates. One hundred years ago, Albert Einstein discovered the general theory of relativity.

It was 100 years ago this month that Einstein delivered four lectures to the Prussian Academy of Sciences in Berlin, which culminated in his discovery of the general theory of relativity. Einstein’s determined pursuit of mathematical equations that describe how the force of gravity works remains one of the most influential scientific discoveries of all time. If you’re planning a party — a general relativity rave, maybe — November 25th is the day it all came together. That’s a Wednesday. But a Thanksgiving toast at dinner the next day works well, too.