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Ok, here's one for the cosmologists [View all]
Been reading a lot about quantum mechanics lately. (Brian Greene) and this hypothetical question baffles me.
1. A cosmologist looks at a star through a high powered telescope.
2. The star is a long, long ways away.
3. It takes the light from that star 1 million years to travel
from that star to the telescope lens, thus the viewer is looking at that star as it was 1 million years ago.
4. Assuming that the laws of physics are correct, that would mean that any calculations concerning this star's nature is based
on 1 million year old information.
5. If all of this is true, then we can never really know the CURRENT nature of this star. It could have turned into a giant black and white hamster and we would never know it. lol
thoughts?
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What makes you think we would know the "current" nature even if we saw the light instaneously?
Cary
Feb 2013
#6
The OP was a question about not knowing the true nature because we "see" light through time & space.
Cary
Feb 2013
#39
All true! We can't know the current nature of the star--only it's past nature. That said...
Moonwalk
Feb 2013
#5
I find the energy transfer time in the sun (and all stars) to be even more interesting...
DreamGypsy
Feb 2013
#15
Some very important knowledge about the cosmos is based on information ~13.5 billion years old.
DreamGypsy
Feb 2013
#13