Need Some Scientific Facts For an Idea of Mine

[YNM]

8 hours ago, vger said:

Considering that the sun's mass isn't actually being increased, would it be a stable black hole even if you could somehow do this?

I'd think so. The only problem is Hawking Radiation. If this portion gets too large the whole thing will evaporate quickly amd possibly undo itself even before it gets too "thin".

The only problem is that we've never observed them in reality.

7 hours ago, kerbiloid said:

total energy of Sun radiation gets released at once

Oddly enough, I'd disagree with this one. Though I'm not sure why.

Edited July 1, 2018 by YNM

[kerbiloid]

15 minutes ago, YNM said:

Oddly enough, I'd disagree with this one. Though I'm not sure why.

Idea is not mine

, but why not. Everything to burn has burnt.

 

 

[monophonic]

5 hours ago, YNM said:

Assuming the total lumimosity doesn't change, the last moment of Sunlight will occur with most of the peak wavelength at γ-ray wavelength, as the surface temperature will reach what today is Sun's core temperature (~ 15 milion K/deg C - doesn't matter this high up). Oddly enough this means the Sun will look "black" to the eye but it's been bombarding us with X-rays and γ-rays for some tens of minutes (wien law gives the max wavelength at 1 Å - for comparison blue light is 4000 Å).

I do wonder whether the redshift from having to climb up from that almost black hole gravity well is negligible or significant at outer planets' distances. Towards the last moments of the collapse of course, I know at the starting normal situation it isn't significant. Unfortunately I am not currently at a situation where I can personally do any calculations.

Edited July 1, 2018 by monophonic
Lousy mobile view

[YNM]

8 hours ago, monophonic said:

whether the redshift from having to climb up from that almost black hole gravity well is negligible or significant at outer planets' distances.

Hmm.

Yeah, this needs some GR.

 

I was searching for "solar interior speed of sound", to try and determine would the external compression have enough time to be propagated to the core or not. Otherwise it'd be like a shockwave from the outside.

Edited July 2, 2018 by YNM

[Xd the great]

@YNM the total brightness increases due to the crazy oxygen fusion. So, add some energy to your math.

On second thought, those energy may take millions of years ro escape. So dont.

@YNM the total brightness increases due to the crazy oxygen fusion. So, add some energy to your math.

On second thought, those energy may take millions of years ro escape. So dont.

[YNM]

1 hour ago, Xd the great said:

the total brightness increases due to the crazy oxygen fusion. So, add some energy to your math.

On second thought, those energy may take millions of years to escape. So dont.

Those energy takes millions of years due to the distance they have to travel through the dense solar material for hundreds of thousands of kilometres. During the collapse, this distance (and so the time it takes them to escape) will be continually shortened. I made a rough consideration for this in my first post in this thread.

For the extra fusion energy, I think we should determine first how the process is happening : Does the whole solar material contracts evenly or is it a push from the outside ? If it's the first then extra energy will come from the core, but if it's the later, it's possible that the extra fusion will comes at the surface of the Sun, instead of the core.

What fusion will happen is likely just hydrogen and helium fusion. Or whatever had time for it.

I don't know the calculations or numbers though.

[kerbiloid]

It's possible to use an extended anthropic principle. 
The process rate in this system ideally matches the requirements of the book author. 
In other star systems rates were different, but no authors survived to tell us about them.
So, any book describing this process can use optimal values required by its author.

Edited July 2, 2018 by kerbiloid

[Xd the great]

I feel some very hoot fusion coming...

[p1t1o]

It sounds a lot like you are describing a Supernova, I believe that stars show signs of instability for some time before it happens, and the final stages occur in minutes. And they can leave behind black holes and neutron stars.

They dont leave much else behind though, there would be no story of survival unless you left the region very quickly, a very long time before.

When you compress a star (stars are compressed, by their own gravity, you can "compress" a star by adding more mass, increasing gravity, add mass to a star and it shrinks) it does heat up, but this heat works to resist the compression. A supernova is the ultimate extension of this, the core shrinks, the rest of the star is blown off by the vast amount of excess heat.

[kerbiloid]

What normally withstands gravity in alive stars?
What disappears (well, gets less) just before a supernova collapse?
Isn't it a gas pressure?

What causes the gas pressure? What repels ions?

Edited July 2, 2018 by kerbiloid

[Steel]

34 minutes ago, kerbiloid said:

What normally withstands gravity in alive stars?
What disappears (well, gets less) just before a supernova collapse?
Isn't it a gas pressure?

What causes the gas pressure? What repels ions?

Radiation pressure [1] in normal stars, or electron degeracy pressure [2] in white dwarves.

 

[1]  https://en.m.wikipedia.org/wiki/Radiation_pressure

[2] https://en.m.wikipedia.org/wiki/Electron_degeneracy_pressure

 

[kerbiloid]

4 minutes ago, Steel said:

Radiation pressure [1] in normal stars, or electron degeracy pressure [2] in white dwarves.

In supernova.

But anyway, it's electromagnetism.

So, if instead of adding more gravity, drain the electromagnetism?

Edited July 2, 2018 by kerbiloid

[Steel]

1 minute ago, kerbiloid said:

In supernova.

But anyway, it's electromagnetism.

Depends on the type of supernova. The mechanisms that trigger then aren't that well understood, but they generally form from white dwarves or massive stars.

[kerbiloid]

2 minutes ago, Steel said:

The mechanisms that trigger then aren't that well understood, but they generally form from white dwarves or massive stars.

Exact mechanisms are unclear. But what about the fundamental interaction?

Also isn't it that what is stopping the cores from fusion?

Edited July 2, 2018 by kerbiloid

[Steel]

3 minutes ago, kerbiloid said:

Exact mechanisms are unclear. But what about the fundamental interaction?

Mass accretion which pushes the mass of a white dwarf over the Chandrasekhar limit. At this point the electron degeneracy pressure can no longer balance against gravity and it collapses.

Edited July 2, 2018 by Steel

[kerbiloid]

Just now, Steel said:

Mass accretion which pushes the mass of a white dwarf over the Chandrasekhar limit.

Forget mass.

Electron pressure - which fundamental interaction?
Fusion bareer - which one again?

[Steel]

1 minute ago, kerbiloid said:

Forget mass.

Electron pressure - which fundamental interaction?
Fusion bareer - which one again?

Electron degeracy pressure is a quantum effect as a result of the Pauli exclusion principal, rather than a fundamental force.

Edited July 2, 2018 by Steel

[kerbiloid]

10 minutes ago, Steel said:

Electron degeracy pressure is a quantum effect as a result of the Pauli exclusion principal, rather than a fundamental force.

OK with that, but usually supernova is not a giant white dwarf.
It's either a big star, or a white dwarf surrounded with not degenerated material.

So, isn't electromagnetism that force which keeps most part of a supernova from collapse until time comes?
As well as a regular star continuously.

Edited July 2, 2018 by kerbiloid