Horizon looks at dark energy - the mysterious force that is unexpectedly causing the uni黑帮高中verse's expansion to speed up. The effects of dark energy were discovered in 1998 but physicists still don't know what it is. Worse,国产剧情www yw193 com its very existence calls into question Albert Einstein's general theory of relativity - the cornerstone of modern physics. The hunt for the identity of dark en...