It's been four years and they still haven't responded to you, a simple "you are welcome" is all we needed.

You’re welcome 😉

In the section where the lecturer talks about Einstein's papers on gravitational waves, he explains that Einstein saw a parallel between his equations and the equations for electromagnetism. When mass is lost in the process of fusing two nuclei, its equivalent in energy is radiated in electromagnetic waves. The parallel is that when mass is lost in the process of fusing black holes, its equivalent energy is radiated in gravitational waves. There are other ways to create electromagnetic waves (other than nuclei fusing), such as is done for radio transmissions, with an appropriate oscillation of electric charge. The creator of the electromagnetic equations (Maxwell) also predicted waves before anyone knew they existed. The lecturer illustrates an appropriate way of oscillating masses so that they will produce gravitational waves, which unfortunately are far too weak to detect. But in the conditions leading up to the fusing of two black holes orbiting around one another, the waves are so strong the waves are detectable. I guess the waves are created in a tiny time before the holes unite. It is not after the two holes join. It is the orbiting and not the joining itself. I guess one has to admit that mass must somehow lie partially outside the event horizon (in the gravitational field), as well as inside, if nothing, including mass, can come back out across the event horizon. But then the same must be true about objects without an event horizon.

Gravity waves are not 2D like waves on the ocean, they are 3D waves in all of spacetime.

Need preliminary lectures but very very important

Agreed; this is true, not just of Barish's talk, but of many lectures/presentations on You Tube: when the speaker is giving a presentation, whether it's a Power Point or with slides or videos, stills, etc. you can hear that they're pointing something out a certain thing on that picture, e.g., a graph of some sort, a chart or a picture of a big section of the sky/space & the stars of which they're speaking, but, though you know they're referring to a particular thing, it can be frustrating when you cannot see what it is they're referring to!!

Some day, my lord, you'll be able to tax them both!

when you work with black hole theory, the planets are basically all just the same as each other: irrelevant

Wave events occur with each merger of 2 black holes; Or neutron stars; or one of each; Probably other objects too.......space-breaking physics!

Gravitational waves are ubiquitous. We just can’t detect them unless they’re extremely strong like two ridiculously massive bodies flying around each other at a “large” percentage of the speed of light.

Sometimes people misspeak or make typos (I didn't go back to find out which one). Incidentally, "typos" is one reason I lament the general lack of mathematical formula support in text editors. If you could just copy the formula from Matlab (or whatever) and paste it into your presentation software, it'd eliminate a source of error.

nomeegal Many physicists commonly shorten momentum and mass terms to just eV and expect that the rest is implied and understood by context. It doesn't seem right to outsiders but it's just a useful conversational shortcut. At no point did he not know the actual dimensions.

Roughly speaking at least by some interpretations of modern physics all particles are just convenient expressions of fields. That's why they expected the existence of the Higgs Boson as an indicator for the Higgs field. The idea of the graviton changed a lot over the decades with the change of ideas about gravity, I think, but in essence given that something is still causing the effect of gravity there might still be an expectation that on the quantum level it can be found in a particle. But it is a special case as gravity is shaping spacetime and most other effects happen within that framework and this is a level deeper than that. I think I stuck out my neck out far enough though because that is probably all very speculative science physicists are still arguing about on all levels.

Just to add to that. The LHC results from the last run should be presented in July-August of this year. If evidence that gravitons exist has been found at the LHC we'll know then, if not, it's probably not going to be possible to determine if they exist with the LHC and we'll have to wait for a more powerful particle accelerator to be built. The successor to LHC is going to be built in Japan and should be completed around 2026.

Black holes are spherical because this is the lowest potential energy state. Rotation might give a bulge but I don't know.

I understood you up until "from"

Good question 🤔

"disproving" dark matter/dark energy makes no sense. What the goal is, is to be able to find out just what it is that makes up 26% & 69% of the mass of the universe; the proportions that the Planck spaceprobe recently came up with, which turned out to be a bit different from what the WMAP mission previously came up with. So just saying this off-the-cuff, uninformed stuff really shows a lack of understanding and/or arrogance on your part.

Very funny, well done!

neither does your intelligence.

HA hahahahaha!!!! LMAO!!

Gravity is the effect of things spinning in space time fabric. So as an effect it definitely does.

It is your dog's nose.