Kant, FTL, and Ideaspace
Episode Stats
Words per Minute
118.16377
Summary
In this episode, we discuss the concept of relativity and how it relates to the speed of light. We also talk about the existence of radio communication and why it can't be a part of reality, and why we should be worried about it.
Transcript
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I spend a lot of time just reading up on concepts that I want to edify myself on.
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Stuff that's not particularly directed to an end.
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And every so often, a couple of ideas bounce together completely unexpectedly,
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Sad to say that this morning I knew next to nothing about Immanuel Kant.
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But before we get to that, we need to discuss relativity.
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One of my pet peeves as a fan of science fiction is how often relativity is ignored when it's such a cool theory.
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The speed of light is not like the sound barrier.
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The speed of light is a fundamental aspect of reality.
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And for this plane, for the sake of this, the horizontal is going to be space.
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So, each space-time event, each one of us, is going to be somewhere in that field.
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So, going down in the past is a cone of all the things that could have affected you.
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Out into the future is everything that you can and will affect, even if you only affect it by light bouncing off of you.
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They, this cone is, you move forward in time and it's light coming off of you.
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Anything outside of those cones do not exist for you.
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So, now let's imagine two people in this field.
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And so, they're obviously a huge distance apart.
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And so, they cannot interact until they move into the future and their light cones reach one another.
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That is the earliest point there can be any interaction between these people.
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An instantaneous, etheric communication device.
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Well, surely these two people, you know, they could just bounce signals off one another.
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Doesn't seem to be any problems with that so far, does there?
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It's not violating causality, it's not twisting the universe into a pretzel.
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Let's take one of these people and accelerate them to a significant fraction of C.
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So, at this point, see, when they both are traveling here, this is because they have the same relative velocity to one another.
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Of course, as far as they're concerned, they're all standing still.
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We're all standing still, it's the world that moves around us.
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But these two people, they can tell when there's a difference between them.
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It doesn't matter which one is accelerating, but there's an acceleration, there's a difference in velocity in regards to one another.
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So, what happens then, is as you start to move through space to a substantial fraction of C, your light cone, which used to be vertical, starts to twist in the direction of your travel.
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So, now you have the one light cone, that looks like this, still vertical cone, according to us.
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And you have the person that started traveling, and they have a slanted cone.
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So, what happens now, when these people try and exchange messages to one another?
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The person with the vertical cone pings out a message across space instantaneously to the person with the slanted cone, and they receive it.
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So, when they ping out a message back to the person that was trying to talk to them, it travels at this angle, arriving in the first person's past.
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They receive a reply to a message before they send the message.
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This is why they say in science fiction, if you have FTL, you can either have causality or relativity.
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As soon as anything travels faster than the speed of light, it violates causality, even if it's something as simple as a radio broadcast.
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Now, that's, of course, assuming that causality is an aspect of reality.
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I mean, certainly everything seems to have a cause, doesn't it?
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And for the record, we know that relativity is true.
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A lot of our technology would not work if Einstein hadn't come up with a theory of relativity.
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Satellites, for instance, are in a different relativistic frame than us.
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If you don't account for relativity, your GPS would not work.
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And the empiricists, as he would describe them,
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Analytic is the reasoning you use to discover a priori.
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So, the statement, all bachelors are single, is a priori.
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Because if you understand the concept of bachelor, you understand that the bachelor is single.
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All bachelors are male, would be another a priori right there.
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Whereas the synthetic involved the outside world.
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Nobody can wake up, you know, come to consciousness, grow up, and just know that gravity bends space and time.
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That things accelerate at 9.81 meters per second towards the Earth.
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You can't just know this stuff, you need to go investigate to figure it out.
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This is the realm where science does wicked, wicked things.
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This is what science is designed to do, is go invest the empirical.
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As far as the empiricists were concerned, this was all there was.
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So, you've got the analytic a priori's and the synthetic a posteriori's.
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Kant suggested that there was a synthetic a priori.
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The type of knowledge that could only be arrived at from investigation, that was still a priori.
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Which is precisely what I was saying about all truth being revelation.
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Kant points out that with this statement, all bachelors are single.
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So the conclusion that the bachelor is single is in the predicate.
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Doesn't say, the same thing does not hold true for math, however.
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You don't start with that knowledge when you say 5 plus 5.
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There is no knowledge of 10 inherent in the 5's.
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There is no inherent conclusion to any of that.
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See, Kant would argue that the analytic a priori's are so self-evident that we don't even notice them.
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A priori's are so self-evident that you just know them and you never even have cause to question that you know these things.
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Whereas with mathematics, we start discovering things that we can know that don't require investigation in the world.
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They're purely metaphysical concepts that we discover through synthetic reasoning.
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Well, Kant, he called it transcendental imagination.
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But I think a better term for modern audiences would be idea space.
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All of these ideas potentially exist in idea space for us to find.
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Some of them, like the a priori's, are self-evident.
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The fact that we even exist in idea space means that we can discover these concepts.
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These would be the synthetic a priori's that we have to go and learn about or to figure out for ourselves before we can notice them.
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And then finally, there's the places that don't exist in idea space.
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It seems like a meaningful phrase, but it doesn't point to anything.
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You can't imagine what neon black would look like.
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The same way, for example, you could imagine a unicorn.
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Or, if you were particularly good with math, you could even imagine a world with different laws of physics.
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The same way you can't imagine what happened before time began.
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And see, it's the limits of idea space and our own ability to observe which imposes upon reality.
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The term Newman means a thing in and of itself.
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So the chair I'm sitting on is presumably its own Newman.
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And that interaction is completely limited to my ability to observe.
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My observations on the universe decide what the universe is going to be.
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It's similar to the term heuristic, where the theory that you go into something with determines what you're going to get out.
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Determines what you pay attention to, what you notice.
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And in fact, the entire concept of space and time are fundamental to our nature as observing beings.
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It doesn't mean that time and space are a part of the universe.
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So now that we've talked about idea space, let's think about different sorts of minds.
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Let's think of different ways that minds could exist, could be organized.
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But when you get right down to it, dogs are not particularly dissimilar from the human.
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So density is something that they're innately familiar with in a way that we aren't.
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Everything the bat observes, he bounces the echolocation off of a tree.
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And you see, I'm using the word feel because we don't have a sense term to describe what the bat is experiencing.
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But at the end of the day, we can relate to it still.
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These are all mundane variants upon our own sorts of minds.
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Even if you go to something as low as an insect, an ant or a grasshopper or a cockroach, these are things that do have urges that we can understand.
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They need to eat, they want to mate, they have a sort of very primitive fear in them.
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They have eyes, they observe, they move, they are very primitive and quite odd.
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But when you get right down to it, they're not fundamentally different from us.
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Well, something that's about as intelligent as a cockroach or an ant or a grasshopper.
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It's far more primitive than the ant or the cockroach because it only has one or maybe four processing units.
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As opposed to however many hundreds of thousands or millions the insect has.
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But I think it's a good comparison, it's a good place to start.
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Because they are very, very complex neural networks, computers.
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Even if they aren't technically a neural network, they are a sort of a mind.
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Now when we experience the computer, we have inputs and outputs from the computer.
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Printers, monitors, keyboards, mice, speakers, microphones.
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But to the computer, none of this actually matters.
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The computer exists in a world that these inputs do affect things.
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But the computer's world is all about the processes going on.
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The mathematical relationships of ones and zeros.
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Now certainly it has a chronometer inside of it.
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But if you imagine a computer experiencing time,
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do you think when it's in hibernate mode, it's experiencing every second tick by?
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Or does it exist within the complexities of the processing power?
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Like I almost imagine the computer mind as being like a sort of web of electrical impulses shooting all over the place.
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Which again is showing my own bias as a creature of space and time.
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But I think it's eminently plausible to imagine that sort of a mind.
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More complex than a modern computer, but that does not exist in space and time.
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Science fiction writers have proposed life on the outside of a sun.
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These would be creatures without a conception of space.
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Space and time are things we project onto the universe, as is causality.
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Just because we can't imagine things without causality doesn't mean that they can't exist.
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It just means that because they don't fit into our idea space, we can't observe them.
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The point of all of this is that faster than light travel should be possible.
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But for something better than us, our descendants.
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Something more advanced, more complex, that has discovered different ways to observe and understand.
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And I know I'm going to get the physicists on here.
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Saying this is a bunch of rhetorical nonsense falling deep into a black hole.
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And how you have this limited understanding of spatial concepts.
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And the possibilities this holds for the future are absolutely fascinating.
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And the implications for how we live our own lives.
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Anyway, there's your weird thought for the evening, folks.