Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 76 (9011 total)
69 online now:
coffee_addict, DrJones*, kjsimons, nwr (4 members, 65 visitors)
Newest Member: Burrawang
Upcoming Birthdays: Coragyps
Happy Birthday: DrJones*
Post Volume: Total: 881,652 Year: 13,400/23,288 Month: 330/795 Week: 31/95 Day: 12/19 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   14C Calibration and Correlations
faith24
Junior Member (Idle past 2106 days)
Posts: 27
Joined: 09-10-2010


Message 13 of 59 (580830)
09-11-2010 4:04 PM


There is very little C-14 to begin with that can be calibrated back to a few 6-10k years based on historical data. I am confused about the half life thing. Can someone please explain what that is? This is confusing.... it is like playing chess - it takes time to learn each pieces have certain moves and all the number of possible moves you can make.

I guess i would have to say the correlation is only as good as your guess assuming the decay rate is a constant.

But somehow people will say " oh but it is constant"!

I am lost right here....

Edited by faith24, : No reason given.


Replies to this message:
 Message 14 by Coyote, posted 09-11-2010 4:21 PM faith24 has responded
 Message 16 by dwise1, posted 09-11-2010 5:24 PM faith24 has not yet responded
 Message 17 by RAZD, posted 09-11-2010 5:29 PM faith24 has not yet responded
 Message 22 by Dr Adequate, posted 09-11-2010 10:43 PM faith24 has not yet responded

  
faith24
Junior Member (Idle past 2106 days)
Posts: 27
Joined: 09-10-2010


Message 15 of 59 (580841)
09-11-2010 5:16 PM
Reply to: Message 14 by Coyote
09-11-2010 4:21 PM


quote:
The quantity of C14 drops by half every 5730 years. We know the approximate amount that a sample started with by the amount in the atmosphere, as shown by the tree-rings.

Every 5730 years that amount drops by half, so we can use that information to estimate the age.


Oh i see. So C-14 are turning back into nitrogen about half rate, then fourth and so on. Hrmm... So the assumption is based on the amount of C-14 in the atmosphere is the same found in plants/animals.

quote:
All the evidence so far shows that it is.

I still don't see how it is a constant? How do i determine what is constant and what is not?

Side note: let me read the irc article first.

Edited by faith24, : No reason given.


This message is a reply to:
 Message 14 by Coyote, posted 09-11-2010 4:21 PM Coyote has not yet responded

Replies to this message:
 Message 18 by JonF, posted 09-11-2010 5:47 PM faith24 has responded
 Message 20 by crashfrog, posted 09-11-2010 9:05 PM faith24 has not yet responded
 Message 29 by chenchen21621, posted 01-20-2011 3:32 AM faith24 has not yet responded

  
faith24
Junior Member (Idle past 2106 days)
Posts: 27
Joined: 09-10-2010


Message 19 of 59 (580859)
09-11-2010 7:20 PM
Reply to: Message 18 by JonF
09-11-2010 5:47 PM


quote:
Physicists understand radioactive decay very well. They can predict what we would see today if radioactive decay rates varied in the past. Since the physics of atomic nuclei is a very fundamental part of how our universe works, it turns out that there are lots of things we would see today if radioactive decay rates varied in the past. We've looked really hard for those things, and they aren't there. We conclude (we do not assume) that radioactive decay rates have been constant for 13-ish billion years.

What does the constant decay rate has to do with the age of the earth? What if the decay rate change, then what happen?


This message is a reply to:
 Message 18 by JonF, posted 09-11-2010 5:47 PM JonF has responded

Replies to this message:
 Message 21 by JonF, posted 09-11-2010 9:19 PM faith24 has not yet responded
 Message 27 by kbertsche, posted 09-12-2010 6:11 PM faith24 has not yet responded

  
faith24
Junior Member (Idle past 2106 days)
Posts: 27
Joined: 09-10-2010


Message 23 of 59 (580874)
09-11-2010 10:45 PM
Reply to: Message 18 by JonF
09-11-2010 5:47 PM


quote:
Physicists understand radioactive decay very well. They can predict what we would see today if radioactive decay rates varied in the past. Since the physics of atomic nuclei is a very fundamental part of how our universe works, it turns out that there are lots of things we would see today if radioactive decay rates varied in the past. We've looked really hard for those things, and they aren't there. We conclude (we do not assume) that radioactive decay rates have been constant for 13-ish billion years.

Whether it is constant or not, that can be debatable. But either way you will have to choose one or the other based on the evidence you believe to go right where it leads you.

Edited by faith24, : No reason given.

Edited by faith24, : No reason given.

Edited by faith24, : No reason given.


This message is a reply to:
 Message 18 by JonF, posted 09-11-2010 5:47 PM JonF has responded

Replies to this message:
 Message 24 by Coyote, posted 09-11-2010 11:27 PM faith24 has not yet responded
 Message 26 by Percy, posted 09-12-2010 9:46 AM faith24 has not yet responded
 Message 28 by JonF, posted 09-12-2010 7:23 PM faith24 has not yet responded

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2018 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2020