The Biggest Ideas in the Universe | 21. Emergence

Erratum: As a couple of people have pointed out, there should be an additional factor of the complex conjugate of the wave function in the expectation value formulas 48:00. See e.g. en.wikipedia.org/wiki/Expectation_value_(quantum_m…

Drawing a rough oval shape and saying "so, here's reality" is probably the coolest move a person can make.

When he does "silly things" is a reminder for us that he's human after all. Love from Chile. Thanks for being such an amazing educator.

A little after 4 pm here in Wales, and I just got back from a visit to the Dentist. What better way to take one's mind off sore teeth & gums, than a new episode of Biggest Ideas with Doctor Sean. Thanks once again Prof. Carroll, for making the World a better place - or one of the Worlds, anyway !!

Sean Carroll is really a philosopher who does physics!

"Something Deeply Hidden" Dr. Sean Carroll, will be in my book collection, thank you so much for training us. ❤

Yay! Thanks, Sean. You absolute rockstar.

I really wish advanced undergrad physics class include information like this. I think it's almost always worth it to have a basic understanding about how the subject of interest fit in to a bigger framework of physics

Sean "never makes a talking mistake" Carroll. Perfect diction, tone & intelligence consistent over time in many, many informative cutting edge physics videos. Many thanks

I believe it was on an episode of Veritasium that a theory proposed in a peer reviewed paper says that, and I'm paraphrasing here, that life if an emergent property of entropy. The idea being that in the aggregate, entropy is more efficiently increased in the presence of life as opposed to the absence of life. If we look at the floor of a forest, the immediate impression is one of disorder, or to rephrase that, in a state of high entropy. Where as if you review the photographs sent back from mars via the various rover missions. The surface of the planet seems to be in a relatively low entropic state. For me this was a very important revelation as I've been wondering for several years now as to what property of the universe it is, that provides the needed systemic or environmental pressure so that life might emerge naturally upon a planet where the building blocks are readily available. We know also that our universe is expanding. And that this expansion is accelerating. Is it possible, that entropy is a naturally emergent property of that expansion? Measurement of that expansion has been rated at so many meters per megaparsec per unit of time. However, it seems to me that the only measurement we could actually produce a quantifiable acceleration is the acceleration experienced by normal matter we can observe. It seems only natural that spacetime, the fabric in which all matter resides, must be expanding and flowing past all the stars, planets, galaxies, etc. At a velocity that enormously dwarves the velocity we observe galaxies travelling outward from the center of the universe. An analogy to this would be a large object being moved slowly down stream by the rapid waters of a river. With only the compression or deformation of spacetime via the presence of celestial bodies of matter. Creating a kind of drag upon spacetime, that naturally transfers some of its kinetic energy to the normal matter of the mass in the universe. If this is true, then we have an answer to what dark energy is comprised. Additionally, we know that when massive objects travel through spacetime that the greater the difference in velocity the more massive the objects become. This is general relativity at work. So if spacetime is flowing past us, then does this not also suggest an answer to dark matter? As spacetime flows past galaxies, so to do the mass of neutrons and protons increase in a corresponding measure. This increase in mass being explained via the manifestation of quark/antiquark pairs within the structure of matter. Thus while locally the differential would be too miniscule to effectively measure, in the aggregate it all adds up. Thus making dark energy, dark matter, and entropy emergent properties of our spherically expanding universe. And yes I am aware that certain assumptions are in place in this description upon which we as of yet lack clear consensus. And there are additional ideas I've been kicking around lately concerning the interior of black holes, the big bang, our eventual heat death, and the ways in which multiple verses (as opposed to a universe. Differentiated from the multiverse idea by way of other verses not overlapping our own) eventually interact via massive gravitational waves which might be described as spherical shockwaves traveling outwards for all time. Eventually, if any other verses do, or have existed and have also experienced heat death, might not the interaction of these shockwaves produce ring verses of much smaller scale than our own universe? In other words these shockwaves intersect each other, and if in the aggregate there is sufficient energy, then perhaps torus shaped verses are the predominant form of verse formation. If this were true, and there were a sufficient number at a high enough density, then the overall universe might be something far more akin to the patterns we see produced on the floor and walls of a swimming pool when light shines through the waters surface and there are enough waves to produce seemingly random peaks and valleys. If this view of the universe at large is correct, then it also suggests an answer to the nature of the big bang. Within our uniformly expanding universe, newtonian laws of physics provide a means for the limitation to the amount of material any given black hole has access. This model however would be invalid in the swimming pool analogy. Suppose if you will that we have the presence of a black hole, in the relatively chaotic system of peaks and valleys, such a black hole might rarely have access to incredible amounts of matter upon which to feed. Presuming that such a black hole could feed until approximately an equivalent amount of energy to that present in our current universe. Then perhaps, via some mechanism this could produce an event such as the big bang. Just my thoughts and ideas on the larger picture of the cosmos. I hope you enjoyed reading this narrative. #endhatrednow

Thanks for the latest video --- I guess you must consider penning a book entitled "The Biggest Ideas in the Universe", with each video being a chapter, or series of smaller books with each book covering a single video!

Thank you Prof. Carroll. Your Mysteries of modern physics - Time, is one of the most mind bending audiobooks I've listened to. This feels like a good supplement to that. Learning physics is very motivating when trying to connect the big ideas to everyday reality and clearing up misconceptions.

Your self-criticized writing while talking has improved over the course of this series. It shows here especially. Been hooked since the beginning, and I'm always looking forward to new releases. Keep em comin!

24:11 - Category Theory sneaking in, at least heuristically

Your opening remarks, about how having a certain complexity causes things to happen that you never would have guessed, is a perfect explanation of why software is so difficult. And it also provides analogy to your vocabulary shift to a chunked-state representation: we discovered "metafunctions" in C++ templates, which were designed to provide parameterized types for making strongly-typed collections and the like. Turned out to be a Turing-complete language that developed its own idioms. That's an extreme example of how we strive to tame software: make it in layers, to produce a hierarchy of complexity. It's so hard to explain how to write "good" functions that express a single level of complexity, and what we're trying for is just why "gas" is not wave packets: once you abstract over it, you need to stick to the items within the emergent description.

Sean, thanks again for do this series!

Love these series of Videos. Absolute masterpiece

I love watching and learning this stuff. Really appreciate your videos my man!

This Buds for you SEAN!

The centre of mass example being precious and the idea of being able to distil a massive amount of information to one small bit not being understood deeply is very interesting. These limits to understanding are never talked about in undergraduate physics.