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Some Observers Perceive the Universe To Be Much Younger Than We Do
StartsWithABang writes: 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. 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.
Some Observers Perceive the Universe To Be Much Younger Than We [Who?] Do
Jeb Bush believes the universe to be somewhere between 4 and 5000 years old, so there's alot of diverse and nuanced opinion on this subject.
A better way to put it is that when you are travelling nearly the speed of light, if you look behind you at the place you are heading away from time seems to stand still for it; the light from your old hometown is redshifted. But light that's coming in from in front of you (and thus, the perceived rate of time) is way higher. Time seems to be moving a hundred times faster than normal as you look at an oncoming blueshifted star. Then, the star passes you and all of a sudden it slows down... from your point of view.
So from the point of view of the fast moving observer, time is sped up in front of them, and nearly frozen behind. As they travel they pass galaxies that are growing old very fast, but leave behind them a frozen universe, that is changing imperceptibly slowly.
When they stop... they are not 'surprised' that the universe is old. They watched it grow old in front of them. Nor are they surprised that their home, now billions of light years away, has not changed much (it looks 'young') because behind them time seemed to stop. The perceived universe makes sense from the viewpoint of the traveler. Point being that there is no paradox. What happens to the fast moving universe would look really weird from inside (because of the starbow effect), but they would be used to it. You know... assuming they survived the X-Ray energy sleeting through them from impact with intergalactic matter.
"I will trust Google to 'do no evil' until the founders no longer run it." Hello Alphabet.
Presuming they were able to detect the CMB - which would NOT look the same in all directions - and "correctly" identify it (i.e., presuming that that's what we've done), they would then also be able to calculate their own relative movement, and correct for it. So they'd reach pretty much the same answer that we do.
http://www.independent.co.uk/n...
This one do? Okay, that is a fair chunk of Christians covered right there, not sure where the rest stand.
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Far less than that. Actually, the next big computer problem is to happen at January 19th 2038.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Some Christians. I am not really the person to defend people whose only defense against the DSM IV definition of delusion is that they are explicitly exempt from it (because else any religion very much fits the definition perfectly), but it should be said that not all of them are THAT delusional. Only a rather tiny minority, and close to 100% of that minority residing in the USA, actually believes that.
Outside the US, new earth rubbish plays no significant role.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
He starts out with the Yuval Ne’eman quote about how less people understand relativistic time than believe in horoscopes. Correct, it seems a lot less because as he goes on to demonstrate even someone as enlightened as he himself doesn't understand relativistic time!
Others have pointed out that talking about a galaxy moving a near light speed is purely hypothetical and not particularly interesting or different from other time-bending phenomena such as black holes. But the thing that makes this all completely meaningless (and shows that he doesn't really understand it) is that relativity tells us that there is no universal "now". It's pointless to talk about how old someone at another point in space (whether 100 lightyears or 13 billion light years from us) sees the Universe as being because you're only specifying 3 of his (at least) 4 space time coordinates, assuming the forth one to be "right now", but there is no "now". The "now" is just a convenience we use when the difference is so small as not to matter to us, but when any of the dimensions gets larger you have to specify all of them to say anything meaningful. You could specify the time dimension as a specific amount of time "passed since the big bang" (instead of "now"), but then the title of Ethans little essay becomes its own answer, demonstrating the meaninglessness of the whole exercise (i.e. "is everything that exists 13.8 billion years after the big bang the same age"?)
Yes, we do have motion relative to the CMB, and this causes one side of the CMB sky to appear hotter than the other. Here's an APOD describing it. So everything discussed in the article already happens to us, here on Earth, but in a much less significant way.
Man, don't even defend that strawman. The ratio of actual Christian fundamentalists espousing young Earth, to those that use their existence to justify their modern progressive liberalism, is at least one in a thousand.
Here's what I notice: Generally, those fundie Christians (you have to go find them) will keep their ideas to themselves, unless pressed.
psst, trying to bust a strawman with a strawman. Cute
They've had a persecution complex forever, and now in my old age, I'm having doubts that it is totally unfounded.
They also have a surprisingly strong grip on one of the US' main political parties. To the point where when you ask that parties candidates if they say believe in evolution, they'll tend to answer you something like "Well, I'm not a scientist", or "There are controversies.
Back to your premise....
Well, all I have to go on is personal experience. I grew up in a town where fundamentalists held sway. Until the early 70's no stores were allowed to open on Sunday. You want the Sunday paper? You drive to another town, Eventually, they allowed newsstands to open for a couple hours so people could get papers on the way home from church. Eventually it went to normal as they lost their iron grip on the town. That was mainly a nuisance, amusing not to think back on.
School - Mandated sex education was 1 - 1 hour class saying if you have sex before marriage, you'll get VD and die.
No evolution was taught, and can you imagine - anything that might allow someone to divine an age of the universe younger than 6000 years old was not allowed. I made it the entire way through grades 1-12 without hearing the word dinosaur.
Grandparents were fundies Ever wake up in the middle of the night with your grams praying at the foot of your bed, or forced to listen to her rail on about how you are going to go to hell all day on Sunday and an hour or so every day?
My experience of all intrusive and rather scary fundies is in opposition to your apparent shy creatures, only wanting to be alloed to live the lives they choose model.
On the other hand, the people that seem to have in in for them, 'progressives' I guess, will take every opportunity to loudly proclaim the fundies' ignorance, and stupidity, and mean-spiritedness, and so on.
You don't have to be progressive (another nice strawman) to find the fundamentalists quite repulsive. Having been raised among them, ignorance and stupidity, and mean spritedness are not unreasonable assessments of their activities.
Can't even have a thread on science without the big pile-on.
If I'm forced to take a side, which in itself seems weird to me in a modern society; well, the choice seems clear.
That statement isn't completely clear. Does that mean you're aligning yourself with science, or that you're going to be trying to force schools to teach religion in science class, agitate for legislation to ban same sex marriage, declare the US a Christian nation, and tell us all that Darwin was the Devil?
Time to campaign to get the Duggars back on TV.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Unfortunately I'm not at all sure that he actually got it right though because I think he has forgotten about General Relativity. He treats the entire universe as if it were a single object at rest in the CMB frame. However it isn't: it consists of many constituent components all with their own individual rest frames.
As we look further away from us galaxies are travelling closer and closer to the speed of light and so appear "slowed down" by time dilation due to the expansion of space itself which you need general relativity to account for. All that travelling close to the speed of light should do is shift which galaxies are slowed by time dilation and which are in almost the same frame and so not slowed. Hence you would see effectively exactly what we see now but it will be different galaxies which are in view because you are in a different inertial frame.
Hence I am not at all sure that he got it right. Certainly I'd like to hear it from a cosmologist before I believe it since GR is far more complex than SR and it is easy to get stung applying SR to a situation which requires GR and hence my cautiousness about whether he is wrong since I'm not a cosmologist. This would far from the first thing that he has got wrong...but it would be the first truly spectacular failure.
I'm a creationist, a Christian. I believe the universe is somewhere around 13.5 billion years old. A true reading of Jewish and Christian bibles will reveal this to be the truth. I'm not here to debate the existence of God, rather to say that as a Christian, God is the one who gave us science. Judaism/Christianity and science are partners not or/or.