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Author Topic:   Doesn't the distance of stars disprove the young earth theory?
Percy
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Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 91 of 138 (573980)
08-13-2010 11:39 AM
Reply to: Message 90 by Taq
08-13-2010 11:20 AM


Re: Hubble
Taq writes:
This is where we run into a problem of definition. The Universe is defined by what we can observe, and the observable universe is 13.5 billion years old by the travel of light. Could our observable universe be part of a larger spacetime that is much older? Many theoretical physicists believe so, some don't. It's a mixed bag.
This doesn't sound right to me if you're thinking there's a relationship between the age of our universe and its size, observable or not.
--Percy

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 Message 90 by Taq, posted 08-13-2010 11:20 AM Taq has replied

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Taq
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Posts: 9972
Joined: 03-06-2009
Member Rating: 5.5


Message 92 of 138 (573989)
08-13-2010 1:05 PM
Reply to: Message 91 by Percy
08-13-2010 11:39 AM


Re: Hubble
This doesn't sound right to me if you're thinking there's a relationship between the age of our universe and its size, observable or not.
What I meant to say is that the Universe is defined by the area that we can observe. The age of the Universe we can see is 13.5 billion years.
From my reading, some physicists have proposed that there are other universes out there in the same space we are in. That is, the expansion of our universe is local. These other universes are just very distant, to far away for the light to have reached us. Therefore, the Universe is not defined as all matter/energy that exists but rather the area that we can observe. That is all I was getting at.

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Taq
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Posts: 9972
Joined: 03-06-2009
Member Rating: 5.5


(2)
Message 93 of 138 (573993)
08-13-2010 1:21 PM


Supernova 1987a
I have always pointed to supernova 1987a as evidence for the constant speed of light. However, in recent reading I have discovered that this isn't entirely correct. What we can show with sn1987a is that the light from this supernova had to take 168,000 years to reach the Earth. How so? You simply use the number of days between flash of the supernova and the illumination of the ring around the supernova to construct one side of the triangle (0.658 years). You then use the angle between the supernova and the ring (0.000224 degrees). That's it. From those two values you can calculate the other leg in the right triangle (the leg between the Earth and the supernova) which is also in days. That calcuation returns 168,000 years. You don't input the speed of light anywhere into the calculation. If you want to calculate the DISTANCE to SN1987a then you have to put in speed for light. However, any speed of light you put in returns the same value for the number of years it would take for that light to reach you.
Just a little different twist on an old piece of evidence.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 94 of 138 (574045)
08-13-2010 6:10 PM
Reply to: Message 90 by Taq
08-13-2010 11:20 AM


Re: Hubble
the observable universe is 13.5 billion years old by the travel of light. Could our observable universe be part of a larger spacetime that is much older? Many theoretical physicists believe so, some don't.
Not quite. The Observable Universe is almost indisputedly part of a much larger space-time, even without inflation. With inflation, it's an unbelievably small fraction of the whole Universe. And there's a good chance the Universe is infinite in extent, in which case what we can see is essentially 0% of what there is!
Also virtually indisuptable is that 13.5bn years ago, the Observable Universe was contained within the volume of an atom. Even if the Universe does extend further back past where we usually place the singularity, the Universe has still passed through this "squeeze point".
heck out the wiki page on De Sitter Universe. In this type of universe there is an event horizon which is defined by the expansion of space where the expansion adds up to the speed of light.
To be clear, there is no one event horizon in de Sitter Space - every observer has his own horizon. This is unlike the single horizon of a black hole.
Radius. It is 13.5 billion light years in all directions.
No, this is a common misconception - understandable, but you need to appreciate the added complexity of our observations being constrained by the speed of light. As we observe further, we are observing the Universe at earlier and earlier times, when it was smaller and smaller. The expansion is also not a velocity and hence not constrained by the speed of light. You may want to ask "how big is the Observable Universe *now*, even though we cannot see it as it is *now*?" The answer is about 46 billion light years in radius.

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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 95 of 138 (574079)
08-13-2010 10:30 PM
Reply to: Message 93 by Taq
08-13-2010 1:21 PM


Re: Supernova 1987a -- and Cobalt decay
Hey Taq,
If you put [blockcolor=white] and [/blockcolor] around your gif you get:
which you then need to center if you want it there.
I have always pointed to supernova 1987a as evidence for the constant speed of light. ... If you want to calculate the DISTANCE to SN1987a then you have to put in speed for light. However, any speed of light you put in returns the same value for the number of years it would take for that light to reach you.
Yep, and one of the interesting things is what the light shows: radioactive decay that has the same brief half-life for come of the Cobalt isotopes that we see today.
So the decay rate has not changed in 168,000 years.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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Dogmafood
Member (Idle past 348 days)
Posts: 1815
From: Ontario Canada
Joined: 08-04-2010


Message 96 of 138 (574129)
08-14-2010 8:20 AM
Reply to: Message 94 by cavediver
08-13-2010 6:10 PM


Re: Hubble
And there's a good chance the Universe is infinite in extent, in which case what we can see is essentially 0% of what there is!
This bit of logic always make my brain twitch.

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Apothecus
Member (Idle past 2410 days)
Posts: 275
From: CA USA
Joined: 01-05-2010


Message 97 of 138 (574131)
08-14-2010 8:26 AM
Reply to: Message 89 by Huntard
08-13-2010 9:53 AM


Ah, quite right. I should have said "...3000 years ago...". But of course I didn't say that, so thanks for the correction, Huntard.
Have a good one.

"My own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose. J.B.S Haldane 1892-1964

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driewerf
Junior Member
Posts: 29
Joined: 08-14-2010


Message 98 of 138 (574166)
08-14-2010 12:07 PM
Reply to: Message 52 by nlerd
03-11-2010 6:25 AM


Re: No and yes
If god didn't do the things in the bible the way it says they were done, how is someone supposed to know what is and is not true in the bible? Unless you mean some other kind of truth? And as for wisdom, old wisdom is not always good wisdom. A few hundred years ago the wise said that the old lady next door with all the cats could be a witch and that you could turn lead into gold if you tried hard enough.
I think "true" or "not true" are categories that don't apply to the bible. The bible was written by the the jews at a time that the scientific outlook was still very poor. they tried to make sense of a world they didn't understand and that was very hostile. (To mention just one aspect of this hostiel world: compare the risk of dying for a woman during birth in a underdevelopped country with that in an industrial country. And even the underdevelopped countries are better than the primitive conditions in which the jews lived then.)
We can read the bible, to try to appreciate how primitive people see the world, but we can't apply criteria like true or not true to this.
Edited by driewerf, : No reason given.

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driewerf
Junior Member
Posts: 29
Joined: 08-14-2010


Message 99 of 138 (574170)
08-14-2010 12:18 PM
Reply to: Message 76 by Apothecus
08-12-2010 2:35 PM


I may be completely off base in my thinking here, but Nuimshaan may have a point.
Imagine that a star became visible to eyes on earth by *insert star formation method here * back in, say, 150,000 BCE, and that that visible star wasn't catalogued until say, 600 CE. In, say, 1975, this star was found by parallax, red shift, etc... to be 300000 light years away. I think he's saying that since we don't know exactly when that light became visible to us here on earth, the age of that star is impossible to know. If we'd have been on earth to make a measurement of 300000 light years away at the moment the star became visible, we'd know that it was born about 300000 years ago...
However...
That's not to say that star is still around. The star could have been blown apart by evil spacefarers 3000 years after it was formed (work with me here), and thus we'd be viewing it not as it is, which is a bunch of space debris and heat, but as it was, which is a nice, pretty star.
But again, I may be talking way out of my arse. Anyone?
I think that quite a lot of your trouble comes from the fact that you stronly underestimate the lifetime of stars. Even very short living stars live easely a few billions of years. Even with our knowledge now, we can't estimate the age of stars with the accuracy of hundredthousands of years. So your whole argument is baseless.

This message is a reply to:
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Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 100 of 138 (574194)
08-14-2010 3:07 PM
Reply to: Message 99 by driewerf
08-14-2010 12:18 PM


driewerf writes:
Even very short living stars live easely a few billions of years.
Stars with a mass of more than twice our sun live less than a billion years. The largest stars live less than 10 million (that's million with an "m") years.
Apothecus's example isn't affected by the actual lifetimes of stars. It was an explanation of how distance affects how long it takes light to reach us. The object emitting the light isn't a pertinent detail of the explanation.
--Percy

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Apothecus
Member (Idle past 2410 days)
Posts: 275
From: CA USA
Joined: 01-05-2010


Message 101 of 138 (574392)
08-15-2010 4:10 PM
Reply to: Message 99 by driewerf
08-14-2010 12:18 PM


Missing the larger point...
Hey there driewerf and welcome...
I think that quite a lot of your trouble comes from the fact that you stronly underestimate the lifetime of stars.
Aside from the fact that if you read up on it, you'll find you're overestimating the age of stars, you seem to miss the point of my (admittedly silly) allegory. The ages I used were entirely arbitrary and were chosen for understandability-related reasons. Relatively small numbers are easier to digest for some than bigger numbers...
So your whole argument is baseless.
Although Huntard found a flaw in my reasoning, the correction I made should make the argument sound. Minus the evil spacefaring species hell bent on stellar destruction, are you suggesting a star couldn't have formed 300000 years prior to its resultant light first becoming visible on earth 150000 years ago?
Have a good one.

"My own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose. J.B.S Haldane 1892-1964

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Nuimshaan
Member (Idle past 4953 days)
Posts: 18
Joined: 08-11-2010


Message 102 of 138 (575078)
08-18-2010 8:35 PM


Distance between two objects is not a clear indicator of age.
You admit that though the stars are far away....whereever they are located....they are alive right NOW.
If I can imagine a distant planet with life on it...I can admit they are over there, and I am here....that in no way determines who's older.
Being there or being here...does not determine who's older.
Thank you, Nuimshaan

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crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 103 of 138 (575083)
08-18-2010 8:43 PM
Reply to: Message 102 by Nuimshaan
08-18-2010 8:35 PM


Distance between two objects is not a clear indicator of age.
In fact that's exactly what it is.
If you know that it takes a week for a letter to travel between point A and point B, then you know that the most recent the letter could possibly be is one week old. It can't be any younger than that, because if it is, you haven't gotten it yet.
Imagine you're getting these week-old letters from your cousin. You're reading the letter just as your own son is born, and in the letter, you read your cousin announcing the birth of his new daughter.
Because of the distance between you and your cousin, you know that your cousin's daughter is at least a week older than your new son. Not because distance means age, but because distance means information is coming from in the past, not immediately.
Many of the stars we see are so incomprehensibly far away that the light takes millions or even billions of years to reach us. Far, far more than the 10,000 years creationists say is the maximum age of the universe. How can the universe contain something older than itself? It's an impossibility; thus, the age of the oldest known object is the youngest the universe could possibly be.

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hooah212002
Member (Idle past 801 days)
Posts: 3193
Joined: 08-12-2009


Message 104 of 138 (575085)
08-18-2010 8:47 PM
Reply to: Message 102 by Nuimshaan
08-18-2010 8:35 PM


You admit that though the stars are far away....whereever they are located....they are alive right NOW.
Not technically so. For instance, if we see a star that is 4 billion light years away, we see it as it was 4 billion years ago.
ABE:
I thought this was what you meant when I responded in Message 74. I guess my drunkenness didn't put me too far off base.
Edited by hooah212002, : No reason given.

"A still more glorious dawn awaits
Not a sunrise, but a galaxy rise
A morning filled with 400 billion suns
The rising of the milky way"
-Carl Sagan

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Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 105 of 138 (575087)
08-18-2010 8:49 PM
Reply to: Message 102 by Nuimshaan
08-18-2010 8:35 PM


Withdrawn.
Edited by Percy, : Crash and Hooah had pretty good responses, removing mine now.

This message is a reply to:
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