Eli5: How can light not experience the passage of time if it travels at 670 million MPH – a measurement of time (and space)

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If light travels at 670 million miles per hour, then that means in one hour it will travel 670 million miles. At 2 hours it will travel 1214 million miles etc. This to me sounds like a measurement of time, just on such a huge scale that we can’t comprehend it. But in the grand scheme of the cosmos this is not that crazy of a scale. I would think it’s just saying light doesn’t experience time *relative* to us. But Einstein says no- no matter what, light’s speed doesn’t change and, what, relativity just doesn’t matter? It feels like a paradox

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Space and time are the same thing. To say something experiences “time” is just saying that it’s moving in the physical direction (space) tangentially to our three dimensions of space. Since light is considered “infinitely fast”, it simply does not have a moment of its existence that is capable of moving in the direction of “time”, it is only “moving” relative to “space” – seemingly “instantly”.

Spacetime is oft misunderstood. People hear that space and time are the same thing but for some reason vehemently refuse to accept that they are indeed, literally, the same thing – our conscious awareness merely exists three dimensionally, so any spatial direction perpendicular to our three dimensions is experienced as “time”.

This video does an absolutely amazing job at describing this in an easy to conceptualize manner that builds upon itself, reducing the requirement for you to integrate all these separate thoughts yourself with intuition.

[Hyperbolic rotations of spacetime](https://youtu.be/qdycfWfAtsM)

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