If light transmitting without media, then

AI Thread Summary
Light can transmit through a vacuum without a medium, which is a fundamental principle of physics. The discussion raises questions about the implications of light transmission on the universe's expansion rate, suggesting it could be at least light-speed. However, the expansion of the universe and the behavior of light in a room are separate phenomena. The conversation concludes that while these concepts are intriguing, they are ultimately distinct and unrelated. The topic is considered resolved, with a focus on the established facts of light and physics.
Steven2007
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then where light transmits to in the universe? Does that mean the universe expanding speed is at least light-speed? Because we know light is energy, it is part of our universe. As if it is like this, the universe expands endless and will become cold and dark.

It sounds impossible to me
 
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Turn on a lamp. Notice the room gets brighter. That has nothing to do with the expansion of the universe. Light does not require a medium---that's just a fact of physics.
 
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