Dimensions and relative magnitude

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Discussion Overview

The discussion revolves around the perception of size in relation to distance, exploring why objects appear smaller when farther away and larger when closer. It touches on concepts from geometry, visual perception, and relativistic effects like Lorentz contraction.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant notes that objects appear smaller at greater distances due to the angles formed between the lines of sight from the observer's eye to the object.
  • Another participant expresses dissatisfaction with the angle explanation, suggesting there may be more complexity involved in how size is perceived, particularly regarding the role of photons and neural processing.
  • A different viewpoint emphasizes that the apparent size of an object is relative to its background and nearby objects, indicating that angular size is the primary information processed by the eye.
  • Some participants propose that the phenomenon of size perception is fundamentally linked to three-dimensional physics, while others question whether there are deeper implications beyond this.

Areas of Agreement / Disagreement

Participants express differing views on the adequacy of the angle explanation for size perception, with some agreeing on its validity while others seek a more nuanced understanding. The relationship between distance perception and Lorentz contraction is also noted as a point of contention, with no consensus reached.

Contextual Notes

Limitations include the lack of consensus on the underlying mechanisms of size perception and the potential influence of neural processing on visual interpretation. The discussion does not resolve the complexities of how photons and angles contribute to perceived size.

Nano-Passion
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Why is it that things appear smaller the farther they are away and bigger the closer they are away? It is almost as if the magnitude of their dimensions (length, width, and height)changes. But in reality it is still the same object.

My cup x distance closer to me than the door may appear 1/6th size of the door itself. It is not as if the object got bigger but it seems as if.

Why do things seem bigger or smaller in relative distances through space? It is interesting because things seem to change size close to the speed of light (lorentz contraction).
 
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The two effects are not related. The difference in size due to distance is simply caused by angles. Drawing two lines from your eye to opposite sides of an object, you can see that the closer an object is, the greater the angle between the lines, meaning it takes up more of your field of view.

Lorentz contraction is the result of an object not being able to travel faster than c. I can't explain very well, but I'm sure that a search on Lorentz Contraction here on the forums would yield plenty of good results.
 
Drakkith said:
The two effects are not related. The difference in size due to distance is simply caused by angles. Drawing two lines from your eye to opposite sides of an object, you can see that the closer an object is, the greater the angle between the lines, meaning it takes up more of your field of view.

Lorentz contraction is the result of an object not being able to travel faster than c. I can't explain very well, but I'm sure that a search on Lorentz Contraction here on the forums would yield plenty of good results.

I'm aware of the triangle and angle explanation. It does not satisfy me. I feel that its too simple, there is might be more to it.

For examples, what causes you to interpret different sizes? Well first you must see the objects, for that your neurons register photons. But how does photons coming from different angles causes the object to appear larger or smaller?

Is this just simple three dimensional physics or are there other implications of it...
 
Last edited:
The apparent linear size of the object is relative to the background or other objects near by.
Your eye only produces information about the angular size of the object. When there is no reference around you cannot tell if you see a big object far away or a small one much closer.
So there is no direct information about the linear size of the objects in the raw signal from the eyes and even less in the photons. It's all in the software (and training of it).
 
Is this just simple three dimensional physics or are there other implications of it...

I would say simple 3d physics.
 

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