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We have a photo of a building that makes accurate and measurable predictions of things like the roof being above the door, and how far, and which parts are tran

We have a photo of a building that makes accurate and measurable predictions of things like the roof being above the door, and how far, and which parts are transparent (windows) and which parts opaque (walls), and how many people could fit inside it. Is that picture as real as buildings get?

AnIdiotOnTheNet 6y ago
Is your claim that the picture is the building? Because that's the equivalent of claiming that the a Penrose diagram is spacetime, instead of a representation of the model. The photo of the building is an accurate diagram of the model of that one individual building. It describes the building, it is not actually the building. However, your model (roof height, walls, location, etc) is the building. If that building is destroyed in a fire and remade to those exact specs, do we not say it is still a building?
- jodrellblank 6y ago
  > "Is your claim that the picture is the building?" You said "a model which makes accurate predictions is as real as real gets". That the picture is the building is your claim here, that there's nothing more real than an accurate model, which I'm countering by absurdum. Wind can turn a turbine, a weather predicting model of wind cannot. You say "the differentiation [between a model and reality] is meaningless", I say a model is a leaky abstraction - when you send a single atom through a Young's double slit experiment and it interferes with itself and generates a wave interference pattern, that's leaking a reality outside the billiard-ball model of atoms, that's one time when the distinction between model and non-model is meaningful. > "If that building is destroyed in a fire and remade to those exact specs, do we not say it is still a building?" If the building is destroyed in the fire, and your model of it isn't, how can you say there is no difference between the building and the model?
  - AnIdiotOnTheNet 6y ago
    > You said "a model which makes accurate predictions is as real as real gets". That the picture is the building is your claim here, that there's nothing more real than an accurate model, which I'm countering by absurdum. My claim is that the model describes a real thing, not that it itself is a real thing, and the extent to which that thing being described is real is a matter of the accuracy of the model. You can model the motion of planets with geocentric epicycles, but that is less real than a model that uses heliocentric ellipses. Let me turn this around for a second: > when you send a single atom through a Young's double slit experiment and it interferes with itself and generates a wave interference pattern, that's leaking a reality outside the billiard-ball model of atoms, that's one time when the distinction between model and non-model is meaningful. Now ask yourself: if we have a 100% accurate model of physics that employs a concept of spacetime such that there are no leaks, no unaccounted for observations whatsoever, then would you say that it matters if spacetime is just some mathematical concept and the real mechanism works differently but produces exactly the same results? I submit that it doesn't. A model that produces perfectly accurate descriptions describes reality in so far as any description of reality can be said to. We don't have perfect models of reality, that is known, however lacking a more accurate model it is meaningless to say that our current ones (which are astonishingly accurate despite being imperfect) don't describe reality.
    - cgriswald 6y ago
      > You can model the motion of planets with geocentric epicycles, but that is less real than a model that uses heliocentric ellipses. This example actually weakens your argument. Heliocentric ellipses are chosen because they explain our model well and importantly are simpler than epicycles; but we can make epicycles arbitrarily accurate by piling on as many of them as you like. So which is real? That Earth and the other planets revolve around the sun or that the sun and other planets revolve around the Earth? > if we have a 100% accurate model of physics that employs a concept of spacetime such that there are no leaks, no unaccounted for observations whatsoever, Let's say I have a box with a green LED, a red LED, and a button. One of the LEDs is always lit. Whenever I press the button, that LED becomes unlit, and the other becomes lit. If I try to open the box, it explodes. My model of how this box works is very simple: A demon is sitting inside the box and touches the LED that becomes lit. When I press the button he gets poked with a tack and switches to touching the other LED. If I try to open the box, he gets angry and blows up. This model is 100% accurate. Every one of these boxes I have seen always behaves this way. Is there a demon sitting in the box?

AnIdiotOnTheNet 6y ago

Is your claim that the picture is the building? Because that's the equivalent of claiming that the a Penrose diagram is spacetime, instead of a representation of the model. The photo of the building is an accurate diagram of the model of that one individual building. It describes the building, it is not actually the building. However, your model (roof height, walls, location, etc) is the building. If that building is destroyed in a fire and remade to those exact specs, do we not say it is still a building?

jodrellblank 6y ago
> "Is your claim that the picture is the building?" You said "a model which makes accurate predictions is as real as real gets". That the picture is the building is your claim here, that there's nothing more real than an accurate model, which I'm countering by absurdum. Wind can turn a turbine, a weather predicting model of wind cannot. You say "the differentiation [between a model and reality] is meaningless", I say a model is a leaky abstraction - when you send a single atom through a Young's double slit experiment and it interferes with itself and generates a wave interference pattern, that's leaking a reality outside the billiard-ball model of atoms, that's one time when the distinction between model and non-model is meaningful. > "If that building is destroyed in a fire and remade to those exact specs, do we not say it is still a building?" If the building is destroyed in the fire, and your model of it isn't, how can you say there is no difference between the building and the model?
- AnIdiotOnTheNet 6y ago
  > You said "a model which makes accurate predictions is as real as real gets". That the picture is the building is your claim here, that there's nothing more real than an accurate model, which I'm countering by absurdum. My claim is that the model describes a real thing, not that it itself is a real thing, and the extent to which that thing being described is real is a matter of the accuracy of the model. You can model the motion of planets with geocentric epicycles, but that is less real than a model that uses heliocentric ellipses. Let me turn this around for a second: > when you send a single atom through a Young's double slit experiment and it interferes with itself and generates a wave interference pattern, that's leaking a reality outside the billiard-ball model of atoms, that's one time when the distinction between model and non-model is meaningful. Now ask yourself: if we have a 100% accurate model of physics that employs a concept of spacetime such that there are no leaks, no unaccounted for observations whatsoever, then would you say that it matters if spacetime is just some mathematical concept and the real mechanism works differently but produces exactly the same results? I submit that it doesn't. A model that produces perfectly accurate descriptions describes reality in so far as any description of reality can be said to. We don't have perfect models of reality, that is known, however lacking a more accurate model it is meaningless to say that our current ones (which are astonishingly accurate despite being imperfect) don't describe reality.
  - cgriswald 6y ago
    > You can model the motion of planets with geocentric epicycles, but that is less real than a model that uses heliocentric ellipses. This example actually weakens your argument. Heliocentric ellipses are chosen because they explain our model well and importantly are simpler than epicycles; but we can make epicycles arbitrarily accurate by piling on as many of them as you like. So which is real? That Earth and the other planets revolve around the sun or that the sun and other planets revolve around the Earth? > if we have a 100% accurate model of physics that employs a concept of spacetime such that there are no leaks, no unaccounted for observations whatsoever, Let's say I have a box with a green LED, a red LED, and a button. One of the LEDs is always lit. Whenever I press the button, that LED becomes unlit, and the other becomes lit. If I try to open the box, it explodes. My model of how this box works is very simple: A demon is sitting inside the box and touches the LED that becomes lit. When I press the button he gets poked with a tack and switches to touching the other LED. If I try to open the box, he gets angry and blows up. This model is 100% accurate. Every one of these boxes I have seen always behaves this way. Is there a demon sitting in the box?