In the Many Worlds interpretation of quantum mechanics, the universal wavefunction is the reality, encompassing all possible histories and futures and all exist. But we are only sensitive to a slice of the wavefunction corresponding to our “world”, and due to the superposition principle, our world can happily do its thing unperturbed by other parts of the wavefunction – other “ripples,” or worlds. And while it may seem like it would be physically impossible to have any connection between worlds, it may turn out to be entirely possible to communicate between them. More About Steven Weinberg: https://www.scientificamerican.com/ar… Sign Up on Patreon to get access to the Space-Time Discord! https://www.patreon.com/pbsspacetime Check…

Sign Up on Patreon to get access to the Space-Time Discord! https://www.patreon.com/pbsspacetime Many Worlds’ interpretation of quantum mechanics proposes that every time a quantum event gets decided, the universe splits so that every possible outcome really does occur. But where exactly are those worlds, and can we ever see them? Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop Sign up for the mailing list to get episode notifications and hear special announcements! https://mailchi.mp/1a6eb8f2717d/space… Guest AuthorAll Guest Author Posts are submitted or additional content Wave Chronicle has added to the website. To be a Guest Author please visit our "Post Your Article" page.More Posts - Website

Sign Up on Patreon to get access to the Space-Time Discord! https://www.patreon.com/pbsspacetime Many Worlds’ interpretation of quantum mechanics proposes that every time a quantum event gets decided, the universe splits so that every possible outcome really does occur. But where exactly are those worlds, and can we ever see them? Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop Sign up for the mailing list to get episode notifications and hear special announcements! https://mailchi.mp/1a6eb8f2717d/space… Guest AuthorAll Guest Author Posts are submitted or additional content Wave Chronicle has added to the website. To be a Guest Author please visit our "Post Your Article" page.More Posts - Website

Sign Up on Patreon to get access to the Space-Time Discord! https://www.patreon.com/pbsspacetime Entropy is surely one of the most perplexing concepts in physics. It’s variously described as a measure of a system’s disorder – or as the amount of useful work that you can get from it – or as the information hidden by the system. Despite the seeming ambiguity in its definition, many physicists hold entropy to be behind one of the most fundamental laws of physics. Entropy Explained Playlist https://youtube.com/playlist?list=PLs… Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop Guest AuthorAll Guest Author Posts are submitted or additional content Wave Chronicle has added to the website. To be a Guest…

Sign Up on Patreon to get access to the Space-Time Discord! https://www.patreon.com/pbsspacetime How many times can I half the distance between my hands? Assume perfect coordination and the ability to localize my palms to the quantum level. 15 halvings get them to within a cell’s width. 33 to within a single atom, 50, and they’re a proton’s width apart. Half the distance 115 times and they’re a single Planck-length apart – 1.6×10^-35 meters. Surely we can keep going – .8, .4, .2 x10^-35 m? Bizarrely, those distances might not even exist in any meaningful way. Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop Sign up for the mailing list to get…

While recent news about the Chinese Long March 5 Rocket made a lot of people very nervous because a 22-ton rocket was going to fall out of the sky, this sort of thing happens all the time. Boosters, dead satellites, and sometimes even old space stations get dropped out of the sky fairly often. While the litter seems a little inconsiderate, this is probably far safer than the alternative. The accumulation of space junk poses a huge risk to all human operations in space especially if we cross the threshold into the chain reaction of exponentially growing collisions known as the Kessler Syndrome. Check out all the Leo Labs Space…

It’s fair to say that black holes may be the scariest objects in the universe. Happily for us, the nearest is probably many light-years away. Unless of course, Planck relics are a thing – in which case they might be literally everywhere. Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop Guest AuthorAll Guest Author Posts are submitted or additional content Wave Chronicle has added to the website. To be a Guest Author please visit our "Post Your Article" page.More Posts - Website

That Einstein guy was a real bummer for our hopes of a star-hopping, science-fiction-y future. His whole “nothing travels faster than light” rule seems to ensure that exploration of even the local part of our galaxy will be an excruciating slow. But Einstein also gave us a glimmer of hope. He showed us that space and time can be warped – and so the warp drive was conceived. Just recently, a couple of papers contend that these are not pure science fiction. Check Out Our Previous Warp Drive Episode https://youtu.be/94ed4v_T6YM Warp Drive Papers Introducing Physical Warp Drive https://drive.google.com/file/d/1Fv14… Breaking the Warp Barrier https://drive.google.com/file/d/1idkN… Check out the Space-Time Merch Store https://www.pbsspacetime.com/shop…

I have good news and bad news. Bad news first: two years ago we reported on the Crisis in Cosmology. Since then, it’s only gotten worse. And actually, the good news is also that the crisis in cosmology has actually gotten worse, which means we may be onto something! The most exciting thing for any scientist is when something they thought they knew turns out to be wrong. So it’s no wonder that many cosmologists are starting to get excited by what has become known as the Hubble tension, or the crisis in cosmology. The “crisis” is the fact that we have two extremely careful, increasingly precise measurements of how…

We know that gravity must cause clocks to run slow on the basis of logical consistency. And we know that gravity DOES cause clocks to run slow based on many brilliant experiments. But I never explained WHY or HOW gravity causes the flow of time to slow down. And I’m not going to explain it now – because in a sense it’s not true. Gravity does NOT warp the flow of time. It’s the other way around – the warping of time causes gravity. Check out the Space-Time Merch Store https://pbsspacetime.com/​​​​ Sign up for the mailing list to get episode notifications and hear special announcements! https://tinyurl.com/yx9cusk5​​​ Guest AuthorAll Guest Author…