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Does anybody here happen to be interested in other dimensions?
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(Applause)
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Alright.
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Well, thank you all for your time... and your space.
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(Laughter)
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Good, I'm glad that one worked here.
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Alright.
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Imagine a world whose inhabitants live and die
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believing only in the existence of two spatial dimensions.
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A plane.
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These Flatlanders are going to see some pretty strange things happen;
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things that are impossible to explain within the constraints of their geometry.
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For example, imagine that one day, some Flatlander scientists observe this:
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A set of colorful lights that appear to randomly appear
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in different locations along the horizon.
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No matter how hard they try to make sense of these lights,
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they'll be unable to come up with a theory that can explain them.
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Some of the more clever scientists
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might come up with a way to probabilistically describe the flashes.
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For example, for every 4 seconds,
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there's 11% chance that a red flash will occur somewhere on the line.
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But no Flatlander will be able to determine exactly when
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or where the next red light will be seen.
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As a consequence, they start to think
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that the world contains a sense of indeterminacy,
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that the reason these lights cannot be explained,
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is that at the fundamental level nature just doesn't make sense.
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Are they right? Does the fact that they were forced
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to describe these lights probabilistically
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actually mean that the world is indeterministic?
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The lesson we can learn from Flatland
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is that when we assume only a portion of nature's full geometry,
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deterministic events can appear fundamentally indeterministic.
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However, when we expand our view
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and gain access to the full geometry of the system,
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indeterminacy disappears.
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As you can see, we can now determine exactly when and where
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the next red light will be seen on this line.
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We are here tonight
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to consider the possibility that we are like the Flatlanders.
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Because, as it turns out, our world is riddled with mysteries
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that just don't seem to fit inside the geometric assumptions we have made.
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Mysteries like warped space-time, black holes, quantum tunneling
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the constants of nature, dark matter, dark energy, etc.
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The list is quite long.
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How do we respond to these mysteries?
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Well, we have two choices:
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We can either cling to our previous assumptions,
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and invent new equations that exist somehow outside of the metric,
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as a vague attempt to explain what's going on,
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or we could take a bolder step, throw out our old assumptions,
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and construct a new blueprint for reality.
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One that already includes those phenomena.
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It's time to take that step.
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Because we are in the same situation as the Flatlanders.
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The probabilistic nature of quantum mechanics
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has our scientists believing
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that deep down, the world is indeterminant.
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That the closer we look, the more we will find
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that nature just doesn't make sense.
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Hmm...
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Perhaps all of these mysteries are actually telling us
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that there's more to the picture.
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That nature has a richer geometry than we have assumed.
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Maybe the mysterious phenomena in our world
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could actually be explained by a richer geometry,
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with more dimensions.
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This would mean that we are stuck in our own version of Flatland.
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And if that's the case, how do we pop ourselves out?
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At least conceptually?
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Well, the first step is to make sure that we know exactly what a dimension is.
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A good question to start with is:
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What is it about x, y and z that makes them spatial dimensions?
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The answer is that a change in position in one dimension
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does not imply a change in position in the other dimensions.
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Dimensions are independent descriptors of position.
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So z is a dimension because an object can be holding still in x and y
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while it's moving in Z.
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So, to suggest that there are other spatial dimensions
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is to say that it must be possible for an object
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to be holding still in x, y and z,
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yet still moving about in some other spatial sense.
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But where might these other dimensions be?
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To solve that mystery, we need to make a fundamental adjustment
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to our geometric assumptions about space.
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We need to assume that space is literally and physically quantized,
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that it's made of interactive pieces.
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If space is quantized,
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then it cannot be infinitely divided into smaller and smaller increments.
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Once we get down to a fundamental size,
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we cannot go any further
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and still be talking about distances in space.
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Let's consider an analogy:
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Imagine we have a chunk of pure gold
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that we mean to cut in half over and over.
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We can entertain two questions here:
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How many times can we cut what we have in half?
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and: How many times can we cut what we have in half and still have gold?
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These are two completely different questions,
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because once we get down to one atom of gold,
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we cannot go any further
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without transcending the definition of gold.
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If space is quantized, then the same thing applies.
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We cannot talk about distances in space
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that are less than the fundamental unit of space
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for the same reason we cannot talk about amounts of gold
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that are less than 1 atom of gold.
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Quantizing space brings us to a new geometric picture.
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One like this,
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where the collection of these pieces, these quanta,
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come together to construct the fabric of x, y and z.
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This geometry is eleven-dimensional.
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So if you're seeing this, you already got it. It's not gonna be beyond you.
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We just need to make sense of what's going on.
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Notice that there are three distinct types of volume
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and all volumes are three-dimensional.
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Distance between any two points in space becomes equal to the number of quanta
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that are instantaneously between them.
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The volume inside each quantum is interspatial,
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and the volume that the quanta move about in is superspatial.
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Notice how having perfect information about x, y, z position,
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only enables us to identify a single quantum of space.
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Also notice that it's now possible for an object
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to be moving about interspatially or superspatially
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without changing its x, y, z position at all.
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This means that there are 9 independent ways
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for an object to move about.
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That makes 9 spatial dimensions.
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3 dimensions of x, y, z volume, 3 dimensions of superspatial volume,
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and 3 dimensions of interspatial volume.
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Then we have time, which can be defined as
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the whole number of resonations experienced at each quantum.
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And super-time allows us to describe their motion through super-space.
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OK, I know this is a whirlwind, a lot faster than I'd like to do it,
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because there are so many details we can go into.
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But there's a significant advantage to being able to describe space
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as a medium that can possess density, distortions and ripples.
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For example, we can now describe Einstein's curved space-time
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without dimensionally reducing the picture.
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Curvature is a change in the density of these space quanta.
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The denser the quanta get, the less they can freely resonate
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so they experience less time.
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And in the regions of maximum density,
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and the quanta are all packed completely together,
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like in black holes, they experience no time.
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Gravity is simply the result of an object traveling straight
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through curved space.
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Going straight through x, y, z space
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means both your left side and your right side
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travel the same distance, interact with the same number of quanta.
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So, when a density gradient exists in space,
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the straight path is the one that provides an equal spatial experience
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for all parts of a traveling object.
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OK, this is a really big deal.
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If you've ever looked at a graph of Einstein curvature before,
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space-time curvature,
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you may have not noticed that one of the dimensions was unlabeled.
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We assumed we took a plane of our world
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and anytime there was mass in that plane we'll stretch it;
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if there was more mass, we stretch it more,
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to show how much curvature there is.
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But what's the direction we're stretching in?
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We got rid of the z dimension.
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We blow over that every single time in our books.
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Here, we didn't have to get rid of the z dimension.
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We got to show curvature in its full form.
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And this is a really big deal.
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Other mysteries that pop out of this map,
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like quantum tunneling –
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Remember our Flatlanders?
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Well, they'll see a red light appear somewhere on the horizon
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and then it'll disappear, and as far as they're concerned,
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it's gone from the universe.
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But if a red light appears again somewhere else on the line,
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they might call it quantum tunneling,
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The same way when we watch an electron,
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and then it disappears from the fabric of space
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and reappears somewhere else, and that somewhere else
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can actually be beyond the boundary that it's not supposed to be able to get beyond.
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OK? Can you use this picture now? To solve that mystery?
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Can you see how the mysteries of our world can transform into elegant aspects
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of our new geometric picture?
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All we have to do to make sense of those mysteries
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is to change our geometric assumptions, to quantize space.
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OK, this picture also has something to say
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about where the constants of nature come from;
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like the speed of light, Planck's constant, the gravitational constant and so on.
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Since all units of expression, Newtons, Joules, Pascals, etc,
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can be reduced to five combinations
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of length, mass, time, ampere and temperature,
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quantizing the fabric of space,
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means that those five expressions must also come in quantized units.
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So, this gives us five numbers that stem from our geometric map.
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Natural consequences of our map, with units of one.
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There's two other numbers in our map.
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Numbers that reflect the limits of curvature.
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Pi can be used to represent the minimum state of curvature,
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or zero curvature, while a number we are calling zhe,
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can be used to represent the maximum state of curvature.
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The reason we now have a maximum is because we've quantized space.
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We can't infinitely continue to go on.
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What do these numbers do for us?
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Well, this long list here is the constants of nature,
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and if you've noticed, even though they're flying by pretty fast,
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they're all made up of the five numbers
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that come from our geometry and the two numbers
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that come from the limits of curvature.
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That's a really big deal by the way, to me it's a really big deal.
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This means that the constants of nature
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come from the geometry of space;
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they're necessary consequences of the model.
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OK. This is a lot of fun because there are so many punch lines,
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it's hard to know exactly who's going to get caught where.
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But, this new map,
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allows us to explain gravity,
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in a way that's totally conceptual now,
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you get the whole picture in your head,
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black holes, quantum tunneling, the constants of nature,
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and in case none of those caught your fancy,
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or you've never heard of any of them before,
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you've definitely just barely heard about dark matter and dark energy.
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Those too are geometric consequences.
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Dark matter, when we look at distant galaxies,
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and watch the stars that orbit about in those galaxies,
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the stars out at the edges are moving too fast,
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they seem to have extra gravity.
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How do we explain this? Well, we couldn't, so we say
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there must be some other matter there, creating more gravity,
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making those effects. But we can't see the matter.
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So we call it dark matter. And we define dark matter as something you can't see!
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Which is fine, it's a good step, it's a good start,
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but here in our model we didn't have to take that kind of a leap.
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We took a leap, we said space is quantized,
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but everything else fell out from that.
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Here, we're saying, space is made up of fundamental parts,
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just the same way we believe air is made out of molecules.
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If that's true, then an automatic requirement is
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you can have changes in density, this is where gravity comes from,
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but you should also have phase changes.
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And what stimulates a phase change?
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Well, temperature.
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When something gets cold enough, its geometric arrangement will change,
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and it will change phase.
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A change in the density here, at the outer regions of the galaxies,
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is going<