Friday, January 02, 2009

Chemical evolution

Creationist like to say they are 6 kinds of evolution and that only the 6th as ever been observed. Those sixth kinds of evolution are as follow:

1. Cosmic evolution
2. Chemical evolution
3. Stellar evolution
4. Organic evolution
5. Macro evolution
6. Micro evolution

Today I wan to address a few videos by Kent Hovind (look on youtube none of his stuff is copyrighted) who says that aside from the 6th, none has ever been observed and are unscientific. As you might have guessed from the title I’ll be talking about his second kind of evolution chemical evolution. Hovind claims that for chemical evolution to be happening hydrogen would have to transform into every element from Helium to Ununoctium (actually he stop at Uranium but since we scientist go up to element number 118). Note he is not completely clueless as he mention the first method throught which we obtaint heavy element in the universe: fusion and the restriction of fusion, i.e that it is not energy efficient after the fusion into Iron. Before I go on to rebutte the thing let me go on his second claim to disprove the possibility of chemical evolution: a chicken and the egg problem for the stars. You see he says correctly that elements are produced in stars and he continu by saying that since stars are made out of element we have a circle without any beginning.

Well let me answer the second part of his argument first (it’s easier), first by pointing out that egg laying animals existed millions of years before chicken so the problem only exist for creationist. Second even if you consider the metaphore for it’s actual sences that the problem is that you have a product that is the sources of the the that produce it, i.e a circle of causation that cannot be started since you would need a first chicken to lay the first egg and a first egg for that first chicken to be born, the problem is inexistant for stars. First, because hydrogen is not created in stars, as a matter of fact all hydrogen in the universe was created at the Big Bang. Second, you do not need anything other then hydrogen to make a star (even if the Big Bang did produce small quantities of other element (notable Helium)). In short, you have an outside supply of the building block for your stars so no chicken and the egg problem, the hydrogen comes from outside the first stars and the first stars produce the first heavy elements.

Now for the first part of the equation, Hovind talk about fusion i.e the proces through which a number of low atomic number nuclei are transformed into one of an higher number. Such as the very well known and observe p-p cycle happening in our first own sun and experience in part here on Earth as part of thermonuclear explosion that transform 4 Hydrogen atom into 1 Helium atom and a shitload of energy. Process such as these exist for many elements up to Iron, but how do we get heavier elements such as Uranium, Colbat, Nickel, Gold, Mercury and Californium?


Well we know of a number of processes to explain that are called r-process, s-process, p-process and rp-process (aren’t astronomer just poetic when comes to name?). All of those involve that collision of an heavy nucleii with something which will eventually create a new heavier nucleii. Both the r and the s process are process involving neutrons colliding with the nuclus of an atom and after a short amount time the neutrons decaying into a proton and an electron (neutron unlike proton are not stable particule) increasing the atomic number of the atom by one. The p-process is special; it is a process through which the weight of an element is actually reduced by colision with a gamma ray and subsequent alpha-decay (emission of an alpha particule, i.e a helium atome nucleus), this change the force binding the nuclus toghether and explains the existance of a few heavy element. The p-process is simple the direct addition throught collision of a proton to an already neutron rich nuclei, changing the atomic number of the element and again producing a new element. Now, none of those process have been observed in laboratory the reason being that you need stellar condition for them to be possible, however there is one more way to produce heavy element and this one as been observed on Earth as evidence by the existance of synthetic elements, i.e element that where constructed in laboratory through a collision of two heavy element or through neutron capture in nuclear reactor. Since we know how to produce these element in our lab AND that we have observed technium (the first artificial element) in stars we know that stars produce heavier element from lighter element.

So in short that the inexistant and unobserved chemical evolution for you… So inexistant that we are using it. So unobserved in fact that we have 6 elements that have not being given a name yet because they have only being observed in laboratory for split seconds. Makes you wonder if the rest of those creationist evolution if as unobserved…

2 comments:

Prakash J. Lakhapate said...

Its very good article.

Pls note that for Big Bang to occur we need two items.

From where these items have come.

I think only Energy was existing initially.

Later on some part of energy is converted into the mass.

Still the question remains as from where this energy has come?

We have to believe that Energy is already existing.

We may call that enrgy as GOD or NATURAL POWER or whatever it may be.

Pls give your comments

P.J.LAKHAPATE
plakhapate@gmail.com

asaathi said...

I've given an answer to your comment in this new post: Primordial Energy.