[Modified Gravity is very important because it shows that gravity begins to behave differently at long distances. This is a very important clue as to how gravity actually works. Jan]

Here’s the video: https://www.youtube.com/watch?v=ERazd-SYk_s

Here’s the video: https://www.youtube.com/watch?v=8HNgIJqeyDw

Here’s the video: https://www.youtube.com/watch?v=GTRLP0qYCmE

Here’s the video: https://www.youtube.com/watch?v=6wfkU5v8D48

Here’s the video: https://www.youtube.com/watch?v=dcCDF0zHzLE

Here’s the video: https://www.youtube.com/watch?v=8zcU85O82XE

Here’s the video: https://www.youtube.com/watch?v=m3YvZKJ54WM

Here’s the video: https://www.youtube.com/watch?v=O_STrKAiuc0

Here’s the video: https://www.youtube.com/watch?v=aGPKpx6pMko

Here’s the video: https://www.youtube.com/watch?v=UUrfaEV3S4k