Radioactive Decay Simplified

[sandslash123]

What's the difference between 2 half-lifes and 3 to 1 ratio?

[Astrosteed]

@sandslash123 After two half lives, then only 25% of the original radioactive material will remain. This means 75% has been converted into the stable byproduct. When 75% is comapred to 25%, it is a 3 to 1 ratio.

[kipling1957]

What is not clear here about radiometric dating (excluding C14 dating), is how we know what the isotope ratio was (the initial state) when the rock was formed, in order to zero our clock. This would seem to be a crucial piece of information in making our age calculation. Presumably we cannot simply assume we can extrapolate backwards to 100% uranium (for example). Or can we? And if so, why? What is the empirical evidence for starting conditions?

[crazy77iii]

The BOTTOM LINE Here is that ALL Dating is Based off of Radioactive Decay. And the Moment at which the emission of the beta particle is Released IS in FACT COMPLETELY STOCHASTIC!!!!! One CANNOT take something that is Completely Random and Get and Average from it!!!!! Why don't people understand that??? If you listen to the young man in this video he says that he can "Expect" the RD to happen in 10 minutes? THAT is COMPELTE Conjecture!!!!

[SentientRaven]

Funny how it (apparently) makes it simpler to replace nuclei with pop corn kernels. ;)

I submit that the analogy would work just as well if you didn't have them self-popping, but in a jar in a microwave oven. Then when asked what makes the nuclei pop, one starts the classic particle physics speech; "Well... first, reality is insane..."

[MissyNatdance]

Very well explained !

Better than my teacher ! haha , thank you i really understand half life now . :D

[garcialovesme]

Very well explained using a familiar analogy! I really enjoyed that!

[Anticitizen54]

We were required to watch this video in my math class xD

[rishabhtwr07]

GOOD USEFUL VIDEO.......///

[wiseyeffect]

Experiments have shown that radioactive decay changes with the solar cycles. It seems that neutrino released from the Sun speeds up radioactive decay on Earth. This changes a lot within the known physics.

[Astrosteed]

@wiseyeffect I've looked into this claim a bit, and it does seem like one team of researchers has come up with this result, but by combining small sets of data across decades of time from different sources using different detectors. It is unclear at this point if the small discrepancy is actually due to a major change to our understanding of neutrino physics rather than callibration errors used in order to cross compare the data they used. Extraordinary claims require extraordinary evidence.

[wiseyeffect]

@Astrosteed the same should be said about man made globalwarming.

[Astrosteed]

@wiseyeffect ?? Huh ?? Global Warming is a non-sequitur here. Your claim that this "changes a lot within the known physics" reveals a misunderstanding of the scientific method. One group getting one marginal result does not mean we should start re-writing textbooks. They haven't even made a prediction that was experimentally verified. A direct test must be done before anyone would seriously consider changing the known physics.

[wiseyeffect]

@Astrosteed I'm not saying we should rewrite anything but if it can be proven it would change many things. I brough globalwarming into the picture because it is happening but the reasons given are BS. I have congress&nasa documents that state what's really going on. There is another body of evidance I'm sure your not accounting for that supports the neutrino theory,and globalwarming.

[rapidracer221]

I have a crap physics teacher so thanks for explaining it alot clearer :)

[weboh2]

Do you know anything about how radiation detectors are used when calibrating lambda? Why would there be an exponential instaneous rate instead of a linear instaneous rate. I noticed you assumed the process is thermodynamic when it is not.

[Astrosteed]

@weboh2 the derivative of an exponential function is an exponential function. Also, there's really no heat making the kernels pop, lol! Not sure what you meant by thermodynamic :) Really, it's the overlapping jiggles of the particles in the nucleus that are unstable, in the sense that there is some small random chance that part of the nucleus will break free from the rest of the nucleus

[weboh2]

@Astrosteed But an exponential function assumes a thermodynamic process where none is. And an exponential rate implies a changing instaneous rate; of which, there is no proof either way.

[tomaz2007]

@weboh2 The probability of a nucleus decaying over a certain time period is constant. So if you have N nuclei, in a time interval of dt, the number of decays will be dN = -A N dt (A is a constant). Integrate this and you get the equation for exponential decay.

[weboh2]

@tomaz2007 Yes, a stupid use of calculus and proof that even by the definition of exponential, decay rates are not constant. Notice dN/dt is not constant and decreases with time. Did you flunk calculus?

[tomaz2007]

@weboh2 I didn't say that it's constant. It does decrease with time, because N decreases, obviously. I said that the *probability* of decay for ONE nucleus is constant for a given time period. Was there a mistake in my derivation? It seems that I don't understand clearly what you're trying to argue. Do you have a problem with the constant probability? Because the exponential decay follows directly from this.

[sambricky]

I just want to say mr. astrosteed you are awesome.This gives me a super clear view of how radioactive dating works. Thank you

[JoshCM9JoshCM9]

I watched your video before and in retrospect ,surprisingly, I didn't quite understand it. I just finished reading Chapter 4 of "The Greatest Show on Earth" and watched your video once more. This time it was obvious that you've dumbed the subject down, and though it didn't appear that way before, it's extremely easy to comprehend. Now I can see why creationists disregard this evidence. They don't understand it and choose never to truly research how it works. Great video. Thanks.

[shorty962]

What do you have to say to creationists that say radioactive decay isn't accurate? When i get into debates with creationists about evolution and i have them backed into a corner, one of thier most used last resorts are claiming that there is no proof the world is 4.5 billion years old. They say that the dating methods aren't accurate. I'm more of an anthropology type so i don't have much of a responce.

[Astrosteed]

@shorty962 the East coast of South America and the West coast of Africa have coastline shapes that fit together like puzzle pieces. They also have identical rock structures and fossils, indicating that they were once connected. The mid-atlantic ridge is where the Earth's plates are speading apart at about 2 cm per year. If you look at the distance between the coasts, about 5,000 km. Then it would take something like 250 million years for them to spread apart. Much older than 6,000 years!

[shorty962]

Yes i have tried to explain how the contonents fit together, and it would impossable for them to drift that far in 6000 years, seeing as how they move at the speed you fingernail grow. But they usually say something like "they had to shrink africa by 40% to make it fit pangea."

Then when i try to explain the "the mapmakers dilemma", they will change the subject and talk about irreducible complexity. They have a habbit of changing the subject when they don't have an answer.

[Astrosteed]

@shorty962 Also, evolution has its own evidence separate from the age of the Earth. With what we can now observe, the DNA evidence alone is enough that we can ignore the entire fossil record. see the 'Ken Miller apes and humans' video for a good place to start.

[shorty962]

I know, but once again, they always change the subject when talking about biological evolution. The big bang and abiogenisis always seem to pop up. Aslo, I am a huge fan of Ken Miller and have seen most of his lectures. I was just hoping that you could give me a dumbed down overview of radioactive decay.

[Astrosteed]

I thought this video was that... so, how do you mean?

Also, if someone claims there is no proof the sky is blue, then you'll have a hard time using reason to get them to agree with you. Similar situation here...

Keep in mind you're unlikely to change their mind on the spot. Just provide information. If you don't mind being frustrated, then don't let people just change the topic. Make them admit they are unable/unwilling to address your question before moving on to another topic.

[skydiveelsinore]

Nice Video!

[logicalthinkingorg]

BTW - Great video Astrosteed! Very informative and a great analogy. Really helped me understand the process better.

[Astrosteed]

Thanks :) Don't burn yourself out arguing with warriorprince1010. It reminds me of the argument sketch from Monty Python. You can present a laundry list of facts and evidence and his response is just "no it isn't".

[logicalthinkingorg]

lol you are right, but i still feel its important to try and keep the record somewhat straight. You made an awesome, easy to understand video that helps people understand the dating process, then you have to deal with scientifically illiterate creationists trying to undermine the science b/c of their religious agenda. Its got to stop ;)

[warriorprince1010]

The facts are that we currently have no dating method. If that annoys you or causes anger that is not my problem. Rocks are not closed systems and knowing what they are made of when formed is impossible.

[logicalthinkingorg]

So im guessing you couldn't find anything to back up your argument, so you opted to just keep repeating it in the hope that it'll sound more convincing. You must have hated high school, given how all those damn textbooks have it all wrong. Anyway, I see that you have made up your mind on this front.

But let me ask you a serious question, how do you figure we can see distant star light thats been in transit for millions of years? That makes the Universe older then 6000 years.

[warriorprince1010]

You are claiming you have radiometric dates for stars? Oh my. Quit talking about unrelated things. I am guessing you now accept radiometric dating is a fantasy of evolutionists and not a concept of science.

[logicalthinkingorg]

lol - first of all, evolution and radiometric dating are two different sciences, and cosmology is different again. But no, you haven't convinced me, I'm sticking with the text books, b/c they are a lot more convincing than your out dated book of myths.

But, seriously, how do you make distant star light that has traversed the vast distances of space for millions of light years before we see it... fit in with your comical 6000 y/o universe fable? Its kinda hard to do, yeah?

[warriorprince1010]

I'll stick with science you can stick with whatever book you want. There is no 600 year universe in the bible, quit strawmanning.

[warriorprince1010]

As we know newly formed rocks often have lead in them. Radiometric dating does not work unless we know the makeup of the rock when it is formed. Radiometric dating is not part of any science we are aware of.

[Astrosteed]

Looking at the ratios of a radioactive isotope to its non-radioactive decay product is what's important, not just the amount of lead. In cases where multiple radioactive isotopes with different half-lives are found in the same rock, they converge to a similar age. This gives us confidence that these results are not due to random variations in the amount of a single element in the rock.

e.g. U238 ->Pb206 with a 4.5billion year half life and U237 ->Pb207 with a 700 million year half life.

[warriorprince1010]

As I have pointed out rocks already have different elements in them, thus the dating emthod cannot possibly work. I am sure you are aware of this. Creation is all we have, there is no science against it.

[Astrosteed]

I see you are no fan of reason... this makes it hard to have a reasonable discussion... e.g. If I showed you a fresh flower, a wilted flower, and a dried flower would you say they have different elements in them, so it's impossible to tell which one is older?!

[warriorprince1010]

Flower = living organism. Rock = not living organism. Try again.

[Astrosteed]

You said "rocks already have different elements in them, thus the dating emthod cannot possibly work." I provided a counter arument and instead of admitting you're wrong you reply with a non-sequiter to point out an irrelevant point. C14 dating is used in organic material like wood or bone. Radioactive dating works.

[warriorprince1010]

I pointed out why you were wrong. Rocks are not alive, what part of that do you not understand?

[Astrosteed]

Actually, you just pointed out an obvious fact and then claimed victory. The reality of the situation is that radiactive dating can be used in both organic and inorganic materials. It is one of the cornerstones of the detrmination of the ages of objects. Really, go out and investigate into it.

[warriorprince1010]

It just doesn't work, sorry. You just need to prove it works, as you simply can't do that then the geological column becomes what we all know it is "fantasy". You can't date rocks or fossils, when we can they will show that all life life died in the last 6000 years or so.

[Astrosteed]

What about the Cosmic Microwave Background? What about geological shifts in the continents? what about the Sun's composition? What about the turnoff point on the stellar main sequence in globular clusters? It is clear that you have a conclusion in mind i.e. the world is 6,000yrs old and you will just ignore or rationalize away all the evidence that obviously disproves your claim. Have the courage to be honest with yourself and go out and investigate the observable evidence.

[warriorprince1010]

No fossil is older than 6000 years. That is what the bible says and there is no evidence to go against this. Creation means design followed by imperfection. Atheism demands accidents forming laws and millions of years. We have no evidence for either.

[Astrosteed]

You clearly have a conclusion in mind and you want to ignore any evidence that rules out your conclusion. I just mentioned a bunch of lines of evidence for things being much older than 6000 yrs, and your respone is "There is no evidence... it says so in the Bible". This is the same as saying "I choose to believe what I was programmed to believe". Really, google "USGS Earth Age" and the first result should be the US geological survey's website. It's a good place to start informing yourself.

[warriorprince1010]

1. You claim that no Lead can be present in a newly formed rock.

2. You claim no rocks are soluble and no elements can enter a rock after it has formed. Both these points are wrong and that is a fact of science. Case dismissed.

[logicalthinkingorg]

Your ignorance to science is amazing, but expected if you believe in the bible.

[warriorprince1010]

In other words you could not prove your hypothesis, so you insulted me. A typical evolutionist.

[logicalthinkingorg]

When you say "evolutionist", you mean the vast majority of the western world and almost every scientist on earth. Look I am not trying to be insulting at all, and I'm not trying to prove my hypothesis, b/c its not mine, its accepted scientific fact and has 150 years of solid peer reviewed evidence to back it up. Im sorry that it goes against your beliefs, but you're just going to have to except it. You can believe in God and except the science of evolution at the same time.

[warriorprince1010]

Science has never been about "how many people agree with you". It is about data and the data supports creation.

[logicalthinkingorg]

What I don't think you understand, is that to be taken seriously, you have to be published in scientific journals. There are over 180,000 articles published in the peer reviewed scientific literature. Last I looked, creationism as exactly 0. What data are you referring to?

[warriorprince1010]

If something is wrong it is wrong, regardless of how many people support it. There are not 180,00 peer reviewed articles about radiometric dating.

[logicalthinkingorg]

There are 180,000 peer reviewed articles on evolution - 0 on creationism.

As for modern dating methods... scientists from every part of the world conduct these dating experiments and all get the same results. You are clearly completely scientifically illiterate on this subject.

6000 years old... lol. seriously? Not only does atomic theory contradict that, but so does cosmology, archaeology, paleontology and geology.

[warriorprince1010]

Evolutionists have given up using any dating method as they give different dates each time and it is based on a deliberately flawed hypothesis.  The surface of the earth was formed in the great flood, so most fossils were formed then as was coal and oil.

[logicalthinkingorg]

This is the problem when you believe ancient scripture written by ignorant men. You see the thing is, warriorprince, in the "real" world you need to provide evidence for your claims. You can't just pull shit out of your ass. Can you show us the peer reviewed scientific evidence for a global flood? The Christian's have had plenty of time and money to present the evidence in the scientific forum, yet there is nothing. So its it possible that you're simply buying into mythical story telling?

[warriorprince1010]

What evidence do you have to show what elements are in rocks when they are found/ Quit trying to make me believe in your faith based evolutionism.

[logicalthinkingorg]

You are in a public forum challenging scientific claims and not backing up anything you say, so you are inviting debate. Evolution has nothing to do with belief or faith, its simply accepting the overwhelming evidence that supports it. I know it contradicts your faith, and that must be unsettling, but you're just going to have to accept it. Evolution is why you're here. If you're really interested in the age of the Earth and what we know to be true, see YT video "watch?v=7XDn5SqE9jc"

[warriorprince1010]

You are constantly avoiding the facts because you are an evolutionist. You are stumped and need to accept it. Rocks are not closed sources, elements get in and out after forming and you have no idea what was present when the rock formed. Science is about data not consensus I am afraid.

[logicalthinkingorg]

Well we agree that science is about the data, and all the 'data' shows the Earth to be about 4.5 billion years old. YOU seem to be avoiding the facts, b/c every time something is presented to you, you simply dismiss it and recycle your same tired argument. Astrosteed has consistently countered your point, and you seem to be the one that is stumped. The fact is this, if your argument is sound, there would be scientific data to support it. Lets see it? And don't post a link to a creation website.

[Joniversity]

warriorprince - Have you ever heard of Plato's Cave? well whether you did or didn't, YOU'RE IN IT!...

BTW, not meant as an ad hominem argument, your nickname... ahhh... sounds a bit gay ( Not that there's anything wrong about it)...

[theonenonlysuperfly]

physics exam this week, this helped alot, thankyou

[hefftatious]

thanks dude

[zecaptaintunaart]

Thank you. That was well explained.

[ninjax010]

what if when you were not looking someone snuck in and turnded up the heat? or turned it down? how do you know it's consitant through the ages?

[Astrosteed]

When it is possible to use multiple radiocative isotopes to date a single sample, they converge on the same value of an age, even though they have different half-lives. So it is consistent with the different elements maintaining the same decay probabilities over time that we now observe in a lab. Not sure if this addresses your question, it was kind of hard to tell what you meant.

[eriku9]

that was amazing!!!!

Thanks for the explanation.

[PENGUINATTACKmusic]

Thank you for the clear explanation. GREAT JOB ASTROSTEED

[Peagl0ssNinja]

THANKYOU!!!!!!!! you have made this so SO much clearer for me!

=] cheers

[PI4eternity]

Astrohead,

I was cloudy about the meaning of radioactive decay and its' application to Archaeology. After watching your video, I'm able to apply the popcorn explanation to apparently complex elements of Uranium, Thorium, Radium and Actinium. The visual aid, graph of percentage of radioactive atoms remaining versus time, was well placed, clear and appeared for an ample amount of time. Great example question to test viewer knowledge. Extend the video for 2 seconds, for a dramatic effect!

[86Cado]

u forgot PU

[payandehrad]

Thank you for taking time to explain this!

[payandehrad]

Wow, thank you! This was great help for me.

[babycuddle2]

Thanx understand now. popcorn is a great way to look at it

[marciaax3]

amazing! i totally get it now. :)

[toomanfilms]

Unforgettable illustration. Mind if use this illus. with my creationist friends? :) Awesome presentation.

[Jspaced]

Great video. I agree with MistahJ77

[TheRedLady1430]

yea.. now i know y they called halflife..

[Raxterdax]

Nicely done! *claps*

[Astrosteed]

You win!!!!! .... my appreciation :) Lookin forwad to your Big Bang Vids too. I've got a bunch of material for CMB anisotropy which is on my to do list of movies to make.

[jas2754]

What a great explanation .. thank you. Probably the best I ever heard!

[TheProdigy00]

well done

[MistahJ77]

phenomenal explaination. you should be a teacher (if you aren't already, lol).

[RobAlone]

Excellent.