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	2022-02-10: The Nature of Space and Time AMA 00:03: ... yet another observer's past and this leads us to the notion of the block universe okay in which all space and all of time they sort of have a unified ...
	2020-12-15: The Supernova At The End of Time 15:01: ... that's it - if we think of time as just a stack of slices of the block universe, a prefered direction of time only emerges in our instantaneous awareness ...
	2020-11-18: The Arrow of Time and How to Reverse It 01:58: ... look at a simple example. We’re going to use our good-old block universe picture, where we have 2-dimensions of space and one dimension of time, ... 02:08: ... block universe just sort of exists a-temporally. The experience of time is had by ... 02:53: ... of time. They just describe the relationship between time slices of our block universe. Time has a symmetry in the sense that the past and future aren’t ... 04:50: ... one particular direction ends up being chosen, we need to return to the block universe. ... 05:43: ... this case, we defined the “up” time direction in the block universe as “towards the future”. But what does this look like going backwards in ... 08:11: ... time. If we think of time as just a series of instances - slices of the block universe connected by the laws of physics, then we can break the symmetry in the ... 01:58: ... look at a simple example. We’re going to use our good-old block universe picture, where we have 2-dimensions of space and one dimension of time, with time ... 02:53: ... of time. They just describe the relationship between time slices of our block universe. Time has a symmetry in the sense that the past and future aren’t ...
	2020-11-11: Can Free Will be Saved in a Deterministic Universe? 00:25: ... episodes, we explored the notion of determinism in the context of the block universe idea that we get from Einstein's ... 03:00: Let's paint a cartoon representation of quantum information in a block universe. 03:05: Two dimensions of space and one of time, the slices of the block universe represent the causal ordering of the universe. 00:25: ... episodes, we explored the notion of determinism in the context of the block universe idea that we get from Einstein's ... 03:05: Two dimensions of space and one of time, the slices of the block universe represent the causal ordering of the universe.
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 13:38: ... - pretty relevant for addressing the  reality of other parts of the block universe.   Alan Foxman struggles with the concept that there’s no ... 12:51: ... we continued our discussion of  determinism in relativity and the block universe,   but this time weaving in what quantum  mechanics had to say about ...
	2020-10-20: Is The Future Predetermined By Quantum Mechanics? 00:16: ... we saw that we could think of the unified spacetime in terms of the block universe, an a temporal entity that sort of just ... 00:31: In a block universe of Einstein's relativity, there's no way to cleanly define the present and so no way to cleanly separate the future from the past. 00:43: To us it looks like a particular slice through the block universe. 01:34: ... it suggests a deterministic universe where every slice through the block universe is completely determined by every other slice, either behind it or ahead ... 02:00: ... the entire block universe is defined, past, present, and future, or everything outside our past ... 02:38: We need to see what quantum mechanics says about determinism and how it plays with relativity and the block universe. 08:24: In the block universe picture, it's tempting to depict this as the entire block multiplying with every quantum event. 08:32: A division in the block universe can only propagate as quickly as the result of that quantum event can become known. 11:27: ... universe of pilot wave theory is really a block universe but unfortunately, no one has convincingly figured out how to make ... 11:39: So it's a very simple block universe and it's not a good representation of ours. 12:23: ... week we introduced the idea of the relativity of simultaneity and the block universe and what this might tell us about the reality of the past and ... 12:49: So does that mean that the idea of a now slice through the block universe is meaningless? 13:11: ... clearly and currently existing to the exclusion of other slices in the block universe. ... 13:27: ... you can ascribe actual existence to one slice of the block universe, to one observer's definition of the present, then you should ascribe ... 13:41: And that fills the block universe past and future. 15:21: That means that at least a short chunk of the block universe has a real current existence, much larger than the plank time. 15:32: Guilherme Marquesani takes issue with my characterization of Einstein as the smartest man in the block universe. 15:38: Dude, I said, block universe not universes. 08:24: In the block universe picture, it's tempting to depict this as the entire block multiplying with every quantum event.
	2020-10-13: Do the Past and Future Exist? 03:26: We sometimes use the term “block universe” or “block time” to refer to this view of all space and time just existing in this 4-dimensional chunk. 03:36: ... flip-book of the block universe has to be played in the right direction to see emergent phenomena like ... 04:01: To us, none of the rest of the block universe exists, because our existence emerges from the forward evolution of a razor-thin slice. 04:41: Nothing “plays” the block universe - it just is, and temporal phenomena like us are just embedded in it, when you look at it in the right way. 05:11: ... block - that’s the idea that this shock-front of the present creates the block universe as it proceeds forward, weaving the past out of ... 05:24: Believe it or not, we can actually science these very philosophical ideas, with just a little help from the smartest guy in the block universe. 05:33: The representation of the block universe that I showed you is very Newtonian. 06:22: ... represent the region of the block universe that we can possibly perceived with a light-cone - signals from things ... 09:23: Imagine that the future is created as the wave of the present sweeping out the block universe. 10:19: ... our present time slice with observers and their remains no part of the block universe that couldn't be considered the past according to someone who lives in ... 10:40: ... that only the present exists, that only the current “slice” of the block universe has a meaningful reality - because it’s impossible to define what that ... 10:54: ... past exists and the future doesn’t - at least in the sense of a growing block universe, again, because the “present” of someone else on your slice of present ... 11:09: ... we’re left with two options: 1) the entire block universe has a meaningful existence; or 2) if you don’t want the future to exist ... 11:28: Nothing outside that section of the block universe can be ascribed a definite reality until you interact with it. 13:07: ... we're officially designating you the coolest dude in the block universe - that means past, future, and present - never mind that all of those ... 04:41: Nothing “plays” the block universe - it just is, and temporal phenomena like us are just embedded in it, when you look at it in the right way. 13:07: ... we're officially designating you the coolest dude in the block universe - that means past, future, and present - never mind that all of those are ... 04:01: To us, none of the rest of the block universe exists, because our existence emerges from the forward evolution of a razor-thin slice.

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