# Quantum tunnel into becoming solid iron

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1. Aug 2, 2015

### Stephanus

Dear PF Forum,
I have no background in physic
In http://math.ucr.edu/home/baez/end.html
1. If an earth size object is left alone (assuming the Sun won't swallow it 2 billions year later). In 101500all of it atoms, oxygen (majority abundant in earth, right), silicon, nitrogen (abundant in atmosphere, right), in short every atom even the heavier ones, uranium, radium, etc... they will become iron?
2. And this iron ball, earth mass, barely chandrasekar (did I type the name correctly) mass will become black hole?
3. If number 2 is true, how long will it take for this iron ball to become black hole.
4. And black hole will evaporate through Hawking Radiation (to photon?). Is this true that an earth size black hole to evaporate completely will takes 2^10^26 years?
5. And finally in simple answer, what is quantum tunnel?

2. Aug 2, 2015

### Staff: Mentor

In the absence of other effects, yes. There are good arguments for protons (and neutrons) to decay earlier, within something like 1045 years (see this reference for example). Even if that estimate is many orders of magnitude off it would still mean matter decays much faster than the timescale of those fusion processes.

No. It would become a ball of iron.

Much shorter.
Wikipedia has an article

3. Aug 2, 2015

### Stephanus

But,

And in the end, what? What about TIME?
Supposed the observable universe become a single black hole and it evaporates away then...?
If the universe reaches maximum entropy nothing changes, the universe doesn't have energy, matter, motion consist only space (or spacetime???), does time stop?
Time dilate, fasten, anything. No single device can measure time.
Grand father clock depends on gravity, wall clock depends on the power of the lithium battery, caesium atomic clock depends on... how fast the thing travels to a rest observer.
But that's all ridiculous, 1 second is 1 second. In one inertial frame, 1 second is 1 second, whether you have atomic clock or not.

So in the end..
1. Does time stop?
2.  Is this question scientifically?
3.  Is this question philosophically?
4. Does the universe still has inertial frame if there's nothing in it. (I don't mean the preffered inertial frame)

4. Aug 2, 2015

### Staff: Mentor

That is the proton decay mechanism I mentioned. It will happen long before larger structures would do that tunneling, if it can happen at all (very likely).
Time won't care. The universe will become a very boring place - eventually all you have are a few isolated particles without any interactions. There is nothing left that could measure time or display a result - so what?

5. Aug 2, 2015

### Stephanus

Hmmh...
Make sense.

But that's all will take place some 101500 years. And we don't even think about the next 50 years when the oil will run out. Fusion power is still the energy of the "future". And It always be. In the future it's still the energy of the "future".
Actually I just wanted to know that "time" is philosophically or scientifically. But that's too deep question and out of topic.
I have satisfied with your answer. Everything will turn to iron and eventually black hole.

6. Aug 2, 2015

### Staff: Mentor

Probably not, because it decays long before that happens.

7. Aug 2, 2015

### Stephanus

Do you mean proton decay?

8. Aug 2, 2015

Right.

9. Aug 4, 2015

### Staff: Mentor

There will never be a time when the universe is filled with nothing. All these decay and evaporation processes leave behind radiation and matter, which are still moving about. The only thing that changes is that the density and temperature will become lower and lower over time.

10. Aug 4, 2015

### Stephanus

What's the matter with the matter? Will they be forever, or disappear because of proton decay? 101500 years if I'm not mistaken?

11. Aug 4, 2015

### Staff: Mentor

1045 years is a better estimate for the proton decay. Actually, it is more like an upper limit - it could be lower, but higher is unlikely.
All atoms will decay, so "matter" in the conventional way won't exist any more. Only photons, electrons, positrons and neutrinos, together with extremely weak gravitational waves, all with a very low density.