Why the Sun Shines Steadily — A New Explanation  Based  on  the  Theory   of Gravity Essence

Jian’an Wang

Department of Physics, Shenzhen University, Shenzhen, China

Email: wja@szu.edu.cn

Abstract

As the central celestial body of the solar system, the Sun has shone steadily for

approximately 4.6 billion years. The core puzzle regarding the physical mechanism of its long-term stable fusion is: why heavy elements do not sink to the core under

gravity, which would terminate hydrogen fusion. Based on the origin theory of gravity established in On the Essence of Gravity, this paper proposes and rigorously

demonstrates that the extremely high temperature in the solar core causes complete ionization of matter, converting all orbital electrons into free electrons, thereby

making the gravitational constant G  = 0. The disappearance of gravity prevents the gravitational sedimentation of heavy elements, maintaining a fusion environment  dominated by hydrogen and helium in the solar core for a long time, which is the   fundamental physical reason for the Sun’s steady shine. The model in this paper   requires no ad hoc assumptions and is fully self-consistent with observed solar

characteristics. It not only solves the core conundrum in mainstream solar physics but also further verifies the scientificity and universality of the essential theory of  gravity.

Keywords: steady solar shine; essence of gravity; gravitational constant; complete ionization; heavy element sedimentation; hydrogen fusion

1 Introduction

The long-term steady shine of the Sun is a prerequisite for life on Earth. Its energy

originates from hydrogen nuclear fusion (proton-proton chain reactions) in the core

region, which requires the core to sustain a high-temperature, high-pressure material environment dominated by hydrogen and helium continuously. However, mainstream solar physics has long faced an irreconcilable core puzzle: the Sun contains heavy

elements such as carbon, oxygen, and iron (about 2% of its total mass). These heavy elements have much higher density and inertial mass than hydrogen and helium. If   gravity were non-zero inside the Sun, heavy elements should continuously sink

toward the core under gravity, gradually occupying and eventually fully filling the core

region, causing solar hydrogen fusion to weaken and terminate completely — this   seriously contradicts the observed fact that the Sun has shone steadily for 4.6 billion years.

On the Essence of Gravity has clearly stated that gravity originates from the

statistical superposition of magnetic moment interactions of atomic orbital electrons; only atoms and ions carrying orbital electrons can generate and respond to gravity. Free nuclei and free electrons, having no orbital electrons, do not participate in

gravitational interactions. Further derivation shows that the gravitational constant G  is not a true constant but a physical quantity dependent on temperature: rising

temperature intensifies atomic ionization, reduces the number of bound orbital

electrons, and thus decreases G. When the temperature reaches the complete

ionization temperature of matter, all electrons become free electrons, the number of orbital electrons is zero, G  = 0 , and gravity vanishes completely [ 1].

Based on this essential theory of gravity, this paper explains the physical mechanism of the Sun’s steady shine fundamentally for the first time: the extremely high

temperature in the solar core causes complete ionization of matter and G  = 0; the disappearance of gravity prevents the accumulation of heavy elements at the solar center, maintaining the long-term stability of hydrogen fusion in the solar core and providing a solid physical basis for the Sun’s long-term steady shine.

2 Theoretical Basis: The Essence of Gravity and the

Temperature Dependence of the Gravitational Constant

2.1 Core Conclusions of the Essence of Gravity

According to the core theory of On the Essence of Gravity, the physical origin of

gravity can be summarized as: gravity is the statistical superposition of magnetic

moment interactions of orbital electrons outside atomic/ionic nuclei, and the essence of gravity is statistical magnetic interaction. This theory clearly presents two key

criteria:

1.       Only atoms and ions carrying orbital electrons outside nuclei can be effectively acted upon by a gravitational field.

2.        Free electrons (without orbital electrons) and bare nuclei (without extranuclear electrons) are not affected by a gravitational field.

These criteria reveal the generation mechanism of gravity at the microscopic level, break the traditional cognition that “gravity is directly related to mass” , and establish the core viewpoint that “orbital electron magnetic moments are the sole source of  gravity” [ 1].

2.2 Temperature Dependence of the Gravitational Constant G

Based on the essential theory of gravity, the magnitude of G  is related to the

proportion of bound orbital electrons in matter: the greater the number of bound orbital electrons, the stronger the statistical superposition of magnetic moment  interactions of orbital electrons, and the larger the value of G; conversely, G

decreases. As a key factor affecting the degree of atomic ionization, temperature directly determines the proportion of bound orbital electrons in matter, so G  is a   function of temperature, i.e., G  =  G (T) . The core relationship is expressed as:

G(T)=G(0)Nb(T)/N0

where G (0)  is the traditional gravitational constant at the low-temperature limit (matter is not ionized, all electrons are bound orbital electrons); N0   is the total number of

electrons in matter; Nb (T) is the number of electrons in bound orbits at temperature T;  is the proportion of gravity-effective electrons, which decreases monotonically

with rising temperature.

When the temperature rises to the complete ionization temperature TI   of matter, all atoms are completely ionized, extranuclear electrons are all converted into free

electrons, and Nb (T) = 0 , so the proportion of gravity-effective electrons is zero. Therefore:

limG(T) = 0， T→TI

This conclusion indicates that when matter reaches a fully ionized state, gravity disappears completely and G  = 0.

3 Physical State of the Solar Core: Complete

Ionization and G = 0

3.1 Temperature and Ionization State of the Solar Core

Observations and theoretical calculations show that the temperature of the solar core is about 1.57 x 107,K (15.7 million K), and the pressure is about 2.5 x 1011,atm. It is

the region with the highest temperature and pressure inside the Sun and the site of hydrogen fusion [4].

The main components of the solar core are hydrogen (about 74%), helium (about

24%), and the rest are heavy elements such as carbon, oxygen, and iron (about 2%). According to the formula for calculating the complete ionization temperature TI   ≈        (where EI  is the atomic ionization energy and K  is the Boltzmann constant), the

complete ionization temperatures of various elements are obtained:

1.       The ionization energy of hydrogen is 13.6 eV, and the complete ionization temperature is about 1.58 x 105,K.

2.       The ionization energy of helium is 24.6 eV, and the complete ionization temperature is about 2.86 x 105,K.

3.       The complete ionization temperatures of light and heavy elements such as carbon and oxygen are on the order of 106,K.

4.       The complete ionization temperature of heavy metals such as iron is about 3.5 x 108,K. Although the solar core temperature does not reach the complete ionization

temperature of iron, it is sufficient to fully ionize all outer electrons of iron atoms,

leaving only a small number of inner electrons, which are also rapidly excited to free electrons at extremely high temperatures, eventually achieving approximate

complete ionization.

Obviously, the solar core temperature (1.57 x 107,K) is much higher than the

complete ionization temperatures of hydrogen, helium, and most heavy elements. Therefore, all matter in the solar core is in a fully ionized state, i.e., all extranuclear electrons are converted into free electrons, and no bound orbital electrons exist.

3.2 Gravitational Constant G  = 0   in the Solar Core

According to the theoretical derivation in Section 2.2, when matter is completely

ionized, the number of bound orbital electrons Nb (T) =  0 , the proportion of gravity- effective electrons is zero, so G  = 0. The matter in the solar core is in a fully ionized state with no bound orbital electrons, which means:

The gravitational constant G  = 0  in the solar core region, and gravity vanishes completely.

It should be clarified that G  = 0  in the solar core only applies to the core region (about 1/4 of the solar radius). In regions outside the core, the temperature gradually

decreases, the degree of ionization weakens, the number of bound orbital electrons increases gradually, and G  increases from 0 to G (0) . Therefore, normal gravity still  exists in the outer layers of the Sun, maintaining the overall structural stability of the Sun, which is fully consistent with the observed characteristics of the Sun [5].

4 Fundamental Mechanism of the Sun’s Steady Shine:

G = 0  Prevents Heavy Element Sedimentation

4.1 Core Puzzle in Mainstream Solar Physics: The

Problem of Heavy Element Sedimentation

In the traditional theory of gravity, the gravitational constant G  is a constant, and

gravity is proportional to the mass of matter. Heavy elements (carbon, oxygen, iron, etc.) inside the Sun have much higher masses than hydrogen and helium, so under gravity, heavy elements should continuously sink toward the solar core — just as   heavy metals inside the Earth sink toward the Earth’s core.

If heavy elements continuously sink to the solar core, two serious consequences will occur: first, the proportion of hydrogen and helium in the core region will drop rapidly, making hydrogen fusion unsustainable; second, the fusion temperature of heavy

elements is much higher than that of hydrogen fusion, causing a sharp rise in the

solar core temperature, triggering intense solar activity, and even terminating the

Sun’s lifespan in advance. However, observations show that the Sun has shone

steadily for about 4.6 billion years, the core region is still dominated by hydrogen and

helium, and heavy elements have not accumulated in large quantities. This

contradiction is a core problem that mainstream solar physics has long been unable to solve [6].

4.2 Solution of the Theory in This Paper: G  = 0   Eliminates

the Driving Force for Heavy Element Sedimentation

Based on the theoretical framework of this paper, G  = 0  and gravity vanish

completely in the solar core, which fundamentally eliminates the driving force for

heavy element sedimentation: the essential reason why heavy elements sink toward the core is the gravitational pull on more massive matter; when gravity disappears

(G = 0), no matter how massive heavy elements are, they will not be pulled by gravity and thus will not sink toward the core.

Matter in the solar core (hydrogen and helium ions and free electrons) is in a fully

ionized plasma state. Under the action of high temperature and pressure, the plasma exhibits a uniform thermal motion state, and heavy element ions are uniformly mixed with hydrogen and helium ions, with no sedimentation caused by gravitational

differences. This uniformly mixed state can be maintained for a long time, keeping the solar core dominated by hydrogen and helium, thus ensuring the continuous  progress of hydrogen fusion.

4.3 Complete Logical Chain of the Sun’s Steady Shine

Combined with the above analysis, the complete physical logical chain for the Sun’s steady shine can be summarized as:

1.       The high temperature of the solar core (1.57 × 107,K) is much higher than the

complete ionization temperatures of various elements, leading to complete ionization of core matter.

2.        In the fully ionized state, all extranuclear electrons are converted into free

electrons with no bound orbital electrons. According to the essential theory of gravity, G = 0 and gravity vanish completely.

3.       G  = 0  eliminates the gravitational driving force for heavy element sedimentation, so heavy elements are uniformly mixed with hydrogen and helium ions in the core

plasma and do not accumulate toward the core.

4.       The core continuously maintains a material environment dominated by

hydrogen and helium, and hydrogen nuclear fusion (proton-proton chain reactions) proceeds steadily and continuously, releasing energy constantly.

5.       The temperature in the outer regions of the Sun decreases, and G gradually

recovers from 0 to G (0) . Normal gravity maintains the overall structural stability of the Sun, and energy is transmitted to the solar surface through the radiative zone and

convective zone, forming stable solar radiation.

This logical chain is closed and self-consistent, requiring no ad hoc assumptions. It perfectly explains why the Sun can shine steadily for a long time and fundamentally

solves the core puzzle in mainstream solar physics.

5 Theoretical Verification and Observational

Compatibility

The mechanism of the Sun’s steady shine proposed in this paper is fully compatible with various observed characteristics of the Sun and can explain phenomena that mainstream theories cannot, further verifying the scientificity of the theory.

1.       Observation of hydrogen and helium proportions in the solar core: Solar

neutrino observations show that the hydrogen abundance in the solar core is about  74%, helium abundance about 24%, and heavy element abundance only 2%, which  is completely consistent with the conclusion of this paper that “heavy elements do not sink and the core remains dominated by hydrogen and helium” [4].

2.       Solar activity cycle: Solar activity (sunspots, flares, etc.) originates from

magnetic field changes in the solar convective zone. In the theory of this paper, G  = 0 in the solar core does not affect the generation of outer magnetic fields (magnetic

fields originate from the relative rotation of charged plasma shells), which is not contradictory to the observed characteristics of the solar activity cycle.

3.        Estimation of solar lifespan: According to the mechanism of this paper,

hydrogen fusion in the solar core can proceed steadily and continuously, and the

estimated total lifespan of the Sun is about 10 billion years, which is highly consistent with existing observational estimates (about 9–10 billion years) [7].

4.       Observation of heavy element distribution: The heavy element abundance in the solar atmosphere is basically consistent with the average abundance inside the Sun, indicating that heavy elements do not sink to the core in large quantities, further

verifying the conclusion of this paper that “G  = 0  prevents heavy element sedimentation” .

6 Discussion and Conclusion

6.1 Discussion

Based on the theory of On the Essence of Gravity, this paper reveals for the first time the fundamental reason for the Sun’s steady shine: complete ionization in the solar   core leads to G  = 0 , and the disappearance of gravity prevents heavy element

sedimentation, maintaining a stable environment for core hydrogen fusion. The core difference between this explanation and mainstream solar physics is that mainstream theories assume G is a constant and cannot explain the problem of non-

sedimentation of heavy elements; this paper clarifies that G  is a function of

temperature, and the characteristic of G  = 0  in the core fundamentally solves this puzzle.

It should be emphasized that G  = 0  in the solar core does not mean the Sun loses

gravity as a whole. In regions outside the solar core (radiative zone, convective zone,

photosphere, etc.), the temperature gradually decreases, the degree of ionization

weakens, the number of bound orbital electrons increases, and G gradually recovers to the traditional gravitational constant G(0) , which can effectively maintain the overall structural stability of the Sun and prevent the Sun from disintegrating due to no

gravity in the core. This structure of “no gravity in the core, gravity in the outer layers” is the key to the long-term stable existence of the Sun [ 10].

In addition, the conclusion of this paper has broader significance: it not only explains the steady shine of the Sun but also provides a new explanatory framework for the  stable evolution of other stars. For stars with masses similar to the Sun, when their core temperature is high enough, the phenomenon of G  = 0 will also occur,

preventing heavy element sedimentation and maintaining long-term stable fusion of stars. For massive stars, the core temperature is higher, the region of G  = 0  is larger, and heavy element sedimentation is completely suppressed until hydrogen and

helium are exhausted in late-stage nuclear fusion, leading to core collapse, which is consistent with observed facts of stellar evolution [8].

6.2 Conclusion

Based on the origin theory of gravity established in On the Essence of Gravity, this   paper analyzes the relationship between the temperature, ionization state of the solar core and the gravitational constant, and draws the following core conclusions:

1.       The solar core temperature (1.57 × 107,K) is much higher than the complete

ionization temperatures of various elements, so core matter is in a fully ionized state, and all extranuclear electrons are converted into free electrons.

2.        In the fully ionized state, there are no bound orbital electrons. According to the essential theory of gravity, G = 0  in the solar core and gravity vanishes completely.

3.       G  = 0  eliminates the gravitational driving force for heavy element sedimentation, making heavy elements mix uniformly with hydrogen and helium ions in the core

without accumulating toward the core, maintaining a fusion environment dominated by hydrogen and helium in the core.

4.        Hydrogen nuclear fusion proceeds steadily and continuously, and energy is

transmitted to the solar surface through the outer layers to form stable radiation,

which is the fundamental reason why the Sun has shone steadily for about 4.6 billion years and will continue to shine steadily for billions of years.

The research in this paper not only solves the core puzzle in mainstream solar

physics but also further verifies the scientificity and universality of the essential

theory of gravity, providing a new theoretical perspective for stellar physics and

stellar evolution research, with important academic value and application prospects.

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