“The total number of people who understand relativistic time, even after eighty years since the advent of special relativity, is still much smaller than the number of people who believe in horoscopes.” –Yuval Ne’eman
It’s been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we’re seeing it as it was in the past. Its age — as it appears — is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old.
Image credit: NASA, ESA, and A. Feild (STScI), via http://ift.tt/1PqFSir.
But it is actually possible for an observer living on another planet, star or galaxy to perceive that significantly less time has passed since the Big Bang, so long as they were moving close to the speed of light relative to the CMB. Paradoxically, if they slowed their speed, they’d find that they themselves were very young, but living in a 13.8 billion year-old Universe.
Image credit: NASA, ESA, Jean-Paul Kneib (Laboratoire d’Astrophysique de Marseille) et al.
Come find out how on this week’s Ask Ethan!
from ScienceBlogs http://ift.tt/1TYp2Ot
“The total number of people who understand relativistic time, even after eighty years since the advent of special relativity, is still much smaller than the number of people who believe in horoscopes.” –Yuval Ne’eman
It’s been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we’re seeing it as it was in the past. Its age — as it appears — is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old.
Image credit: NASA, ESA, and A. Feild (STScI), via http://ift.tt/1PqFSir.
But it is actually possible for an observer living on another planet, star or galaxy to perceive that significantly less time has passed since the Big Bang, so long as they were moving close to the speed of light relative to the CMB. Paradoxically, if they slowed their speed, they’d find that they themselves were very young, but living in a 13.8 billion year-old Universe.
Image credit: NASA, ESA, Jean-Paul Kneib (Laboratoire d’Astrophysique de Marseille) et al.
Come find out how on this week’s Ask Ethan!
from ScienceBlogs http://ift.tt/1TYp2Ot
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