Gravitational waves are ripples in the fabric of space-time caused by massive events like the collision of black holes.

“they will create a ripple in the fabric of space and time emanating at the speed of light a ripple because as they come closer and closer they they spiral and faster and faster and then they come together and right at that instant poof there's a ripple”

LISA is scientifically valuable even if it fails to detect supermassive black hole mergers because it will capture gravitational waves from millions of stellar-mass binary objects.

“I want to make sure that y'all know that Lisa would still be great even it would not detect any of the massive black holes. And that is because as soon as as Lisa turns on, um you're going to be able to detect all of the uh the individual black hole b stellar mass black hole binaries”

She argues that gravitational waves are uniquely valuable for observing the early universe because, unlike light, they do not interact strongly with matter and can traverse the cosmos unimpeded.

“So, this distinguishes our access to the early universe from what our normal telescopes can bring to us, which is this 400,000year barrier really. And the gravitational waves would just plow right past that.”

Gravitational waves provide data about the structure of spacetime and the nature of the universe in a manner analogous to ripples on a pond.

“gravitational waves are essentially uh to the universe and space and time as say ripples are in a pond right so if you see ripples going on in a pond or any body of water you can deduce things about that pond what is the water made out of is there duckweed on the top how deep is it”

Gravitational waves could potentially be used for encrypted communications that cannot be blocked.

“encrypted communications in a way right it's like you know i'm going to take my look two little pulsars binary pulsars and i'm going to move them in this way to create a series of uh you know x's and o so it's secret messages”

Gravitational waves serve as a distinct and valuable method for observing the universe compared to electromagnetic radiation or particle-based detection.

“the latest one which it was gravitational waves right we we have detected neutrinos right that was amazing we do cosmic we detect cosmic rays particles directly coming from far away we have electromagnetic radiation and we have gravitational waves”