How Does Simultaneity Affect Our Understanding of the Universe's Age?

[cephied]

i am very new to this forum so i don't know if this posting is inappropriate in anyway. I had my only other posting removed so... with that being said, i am looking to better understand the implications of simultinaity as it pertains to the age and expansion of the universe. From the perspective of the earth, the universe seems to be somewhere in the neighborhood of 12 to 15 billion years old, but to a particle that has been traveling at near the speed of light since the big bang, the universe is nascent. Is this corrrect?

 

[Thrice]

Correct. Proper time is an important concept though. From the universe's frame of reference, it is 13.7 billion years old. Relativity didn't change the laws of physics. It still takes X years for event Y to happen. It's just that clocks outside Y's frame will measure different values.

 

[HallsofIvy]

Since this is a question rather than a tutorial, I am moving it to a physics thread.