Space Time Ripples and Einstein's Legacy
Headline news was made in 2016 when the detection of gravitational waves, caused by the collision of two black holes, was confirmed by the Laser Interferometer Gravitational-Wave Observatory (LIGO). And earlier this month, another ripple was detected! The observed ripples in the fabric of space-time validate a key prediction in Albert Einstein's theory of general relativity. One hundred years old, the theory continues to astonish scientists with how correct it is. LIGO’s discovery signals a new era of astronomy and a new way of understanding the warped side of the universe.
Janna LevinPhysicist and astronomer
Nergis MavalvalaCurtis and Kathleen Marble Professor of Astrophysics and Associate Dep...
Lisa RandallProfessor of Physics, Harvard University; Author, Dark Matter and the...
Priyamvada NatarajanProfessor, Astronomy and Physics Departments, Yale University
Ira FlatowHost and Executive Producer, "Science Friday," PRI
- 2016 Festival
Albert Einstein famously predicted the existence of gravitational waves in 1916 based on his theory of relativity, and since then many not steeped in theoretical physics have struggled to understand even the basics of his theory. Watch as physicists Nergis Mavalvala, Janna Levin, and Lisa Randall team up to explain the concept of gravitational waves for a lay audience:
Although Einstein’s calculations told him that gravitational waves must exist in theory, he had no way of actually proving his own calculations were correct. Scientists have doggedly tried to find proof ever since, without success — that is, until LIGO. Standing for the Laser Interferometer Gravitational-Wave Observatory, LIGO allowed scientists to collect the proof that had eluded them for nearly a century.
How Does it work?
These aren’t gravitational fluctuations from our cosmic neighborhood, though. When two black holes 30 times more massive than our own collide millions of lightyears away, the change that LIGO measures on Earth is smaller than the width of proton.
History has relatively few examples of decades-long projects ending in success, and LIGO stands out as an instance where over 50 years of research, funding battles, and technological limitations resulted in an unequivocal triumph.
Big IdeaThere is this sense that this obscure experiment that nobody had ever heard came out of the blue, turned on, and succeeded. It was actually a 50-year campaign. It was a really arduous campaign. There were a lot of battles along the way, and I liken it to a climbing Mount Everest story where not everyone makes it to the top.Janna Levin
Not only were physicists fighting for funding and resources, but they were also tirelessly working out any and all wrinkles in the theoretical calculations. The ability of scientists today to breathlessly interpret the highly complex data sets that LIGO produces rests in no small part on scientists who laid the theoretical groundwork decades before.
If two LIGO facilities can produce such extraordinary results, what could a network of LIGO facilities accomplish? And what would be the benefit of a LIGO setup floating through space? These are projects that are in the works — watch as Priyamvada Natarajan and Lisa Randall talk through implications of these innovations: