B Does the Universe prefer certain kinds of matter based on the laws in place?

[LightningInAJar]

My understanding is when a star creates new matter it has an affinity towards iron? Does the universe on a whole favor certain elements based on the laws in place? Certain complexity level and certain physical characteristics are ideal and the farthest from those things the stronger the force to get back to it?

 

[Filip Larsen]

Perhaps https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements and the other topics it links to will answer some of your questions, or at least allow you to ask more specific questions.

 

[Borek]

My understanding is when a star creates new matter

It doesn't create a "new" matter, it converts one elements into another.

it has an affinity towards iron? Does the universe on a whole favor certain elements based on the laws in place?

More like thermodynamics make the universe to have an affinity towards things having the lowest energy. Iron nucleus is one of them - broadly speaking you can convert any other elements to iron and gain some energy from the process, but to convert iron into any other element you need to add energy.

Certain complexity level and certain physical characteristics are ideal and the farthest from those things the stronger the force to get back to it?

In a way you can call iron to be "ideal" in terms of energy, yes.

A bit like a ball in a half sphere bowl - it may jump a bit initially, it may roll to sides initially, but in the end it will always rest in the same spot.

 

[LightningInAJar]

I am just curious about the elemental level because I was wondering if the universe has any favoritism towards certain biological configurations as well. I know life itself wasn't possible for most of the universes' history, but I am wondering if there is anything special about what exists now in the proportions that are. I hope life isn't just random and won't be mowed over too easy because the long term laws won't allow it.

 

[berkeman]

I am just curious about the elemental level because I was wondering if the universe has any favoritism towards certain biological configurations as well. I know life itself wasn't possible for most of the universes' history, but I am wondering if there is anything special about what exists now in the proportions that are. I hope life isn't just random and won't be mowed over too easy because the long term laws won't allow it.

Yes, you are special.

 

[PeterDonis]

My understanding is when a star creates new matter it has an affinity towards iron?

Where are you getting this from? A reference would help.

 

[DaveC426913]

More like thermodynamics make the universe to have an affinity towards things having the lowest energy. Iron nucleus is one of them - broadly speaking you can convert any other elements to iron and gain some energy from the process, but to convert iron into any other element you need to add energy.

Does the universe on a whole favor certain elements based on the laws in place?

What Borek said, above. Look where iron is:

 

[PeterDonis]

Look where iron is

I've always been bothered by diagrams like that one because the binding energy is actually negative; the curve should really be shown inverted, with iron at the bottom, not the top.

 

[Vanadium 50]

because the binding energy is actually negative;

You probably don't like the fact that current flow is opposite the electron flow too.

 

[PeterDonis]

You probably don't like the fact that current flow is opposite the electron flow too.

Well, Benjamin Franklin said so, right?

 

[phinds]

I know life itself wasn't possible for most of the universes' history

It is unfortunate that you "know" this, since it isn't true. In our solar system alone, life started less than a billion years after the solar system formed. There were galaxies that formed MUCH earlier --- they started forming roughly 12.5 billion years ago and there's no reason to believe that life was not possible as early in the existence of those galaxies as it has proven to be in our solar system. That would put the possibility of life starting at somewhere around 2 billion years into the life of the universe, or in other words, life has been possible for over 80% of the life of the universe.

 

[LightningInAJar]

It is unfortunate that you "know" this, since it isn't true. In our solar system alone, life started less than a billion years after the solar system formed. There were galaxies that formed MUCH earlier --- they started forming roughly 12.5 billion years ago and there's no reason to believe that life was not possible as early in the existence of those galaxies as it has proven to be in our solar system. That would put the possibility of life starting at somewhere around 2 billion years into the life of the universe, or in other words, life has been possible for over 80% of the life of the universe.

Wasn't the universe entirely too hot for quite a while after the big bang?

 

[phinds]

Wasn't the universe entirely too hot for quite a while after the big bang?

Yes, that's WHY it took the 2 billion years I estimated. First the universe had to cool down enough for matter to form from the plasma. This took about 400,000 years and then the first Galaxies had to form (another, very approximate, billion years) and then life could have arisen (another 1 billion).

Actually, I think the Webb is finding galaxies that are younger than what I have stated, but that's not really the point. My 2 billion is more like an upper bound.

 

[berkeman]

Thread closed temporarily for Moderation...

 

[berkeman]

After some cleanup, thread is reopened.

 

[LightningInAJar]

Yes, that's WHY it took the 2 billion years I estimated. First the universe had to cool down enough for matter to form from the plasma. This took about 400,000 years and then the first Galaxies had to form (another, very approximate, billion years) and then life could have arisen (another 1 billion).

Actually, I think the Webb is finding galaxies that are younger than what I have stated, but that's not really the point. My 2 billion is more like an upper bound.

So you're saying life was possible between about 2 billion years after big bang and the 11.8 billion years after? Are there predictions of when there won't be enough energy left in the universe for life to be possible?

 

[phinds]

So you're saying life was possible between about 2 billion years after big bang and the 11.8 billion years after?

Yes, that is exactly what I said.

Are there predictions of when there won't be enough energy left in the universe for life to be possible?

Not that I'm aware of other than that it will be orders of magnitude beyond the current age of the universe.

 

[Aldarion]

My understanding is when a star creates new matter it has an affinity towards iron? Does the universe on a whole favor certain elements based on the laws in place? Certain complexity level and certain physical characteristics are ideal and the farthest from those things the stronger the force to get back to it?

As I understand it, the more complex the element, more energy is required to create it. And some elements may only be created in stars of certain size.

Iron is the cutoff point because iron is the heaviest element that is created in stars of normal size, that is, through nuclear fusion. Any elements heavier than iron require additional input of energy, i.e. a supernova. And heavier the element is, less likely is it to be created.

 

[Ibix]

As I understand it, the more complex the element, more energy is required to create it. And some elements may only be created in stars of certain size.

Iron is the cutoff point because iron is the heaviest element that is created in stars of normal size, that is, through nuclear fusion. Any elements heavier than iron require additional input of energy, i.e. a supernova. And heavier the element is, less likely is it to be created.

Not quite. The point is that elements above iron can be created by fusion, but the process absorbs energy rather than releasing it. So heavier metals do get created in very small quantities in stars, but only in large quantities once the star runs out of lower mass elements and is no longer able to generate energy by fusion, so collapses and then explodes.

 

[PeterDonis]

As I understand it, the more complex the element, more energy is required to create it.

It's not that simple. Any stable atom will have less energy than its constituent particles would if they were isolated and not bound together. So from that point of view, creating, say, a He-4 nucleus from two free protons and two free neutrons, or even from two deuterium nuclei, emits energy. That is why nuclear fusion is an energy source, for example in the Sun. And further fusion reactions can in turn emit more energy as they create larger nuclei, up to iron (Fe-56). After that point, fusion reactions no longer emit energy; they require energy. (Fission reactions, where larger nuclei break up into smaller ones, can, OTOH, emit energy when they start with nuclei heavier than iron. That's why, for example, uranium and plutonium can be used to make reactors and bombs.)

The reason fusion reactions haven't already consumed all the light elements in the universe and turned them into iron is that for them to happen, the particles to be fused have to be very, very close together. Since nuclei are positively charged, they repel each other, so it takes a very specific set of conditions to allow fusion reactions to happen. Except for a few human experiments, the only places those conditions exist in the universe are in the cores of stars or supernova explosions.

some elements may only be created in stars of certain size.

This is because fusion reactions beyond hydrogen-to-helium require progressively more extreme conditions to happen, which require larger stars in order for their cores to meet those conditions.

Iron is the cutoff point because iron is the heaviest element that is created in stars of normal size, that is, through nuclear fusion.

And the reason for this is, as noted above, that iron (Fe-56) is the last point at which fusion reactions emit energy.

Any elements heavier than iron require additional input of energy, i.e. a supernova. And heavier the element is, less likely is it to be created.

For elements heavier than iron, yes, this is basically correct.