%0 Journal Article
%T Exploring Gravitational Soliton
%A Bi Qiao
%J Journal of Modern Physics
%P 594-612
%@ 2153-120X
%D 2025
%I Scientific Research Publishing
%R 10.4236/jmp.2025.164032
%X This paper constructs a four-dimensional gravitational soliton solution that strictly satisfies Einstein&#8217;s vacuum field equations, revealing the intrinsic connection between strong-field nonlinear gravity and weak-field linear theory, and proposes a nonlinear unified mechanism for electromagnetic-gravitational interaction. Based on light-cone coordinates and transverse plane polarization structures, a metric form with a <math xmlns='http://www.w3.org/1998/Math/MathML'>
 <mrow>
  <msup>
   <mrow>
    <mi>sech</mi></mrow>
   <mn>2</mn>
  </msup>
  <mrow><mo>(</mo>
   <mrow>
    <mi>k</mi><mi>u</mi></mrow>
  <mo>)</mo></mrow></mrow>
</math>

 type envelope is developed, and its waveform stability is shown to arise from the dynamic balance between nonlinear self-interaction terms and spacetime dispersion effects. The study demonstrates that in the weak-field limit, the soliton degenerates into linear gravitational waves, whose polarization mode <math xmlns='http://www.w3.org/1998/Math/MathML'>
 <mrow>
  <msub>
   <mi>h</mi>
   <mrow>
    <mi>i</mi><mi>j</mi></mrow>
  </msub>
  <mo>=</mo><mi>A</mi><msup>
   <mi>&#x03F5;</mi>
   <mo>+</mo>
  </msup>
  <mo>+</mo><mi>B</mi><msup>
   <mi>&#x03F5;</mi>
   <mo>&#x00D7;</mo>
  </msup>
  </mrow>
</math>

 strictly corresponds to a spin-2, zero-mass graviton, indicating that gravitons are essentially low-energy approximations of nonlinear fields. Further, through the generalized gauge transformation theory, it is shown that two electromagnetic optical solitons in the strong-field region can nonlinearly couple into a gravitational soliton. This process degenerates in the weak-field limit to photon-graviton conversion, supporting the gauge symmetry unification of electromagnetic and gravitational interactions. Additionally, it is predicted that the characteristic waveform of the soliton (such as the <math xmlns='http://www.w3.org/1998/Math/MathML'>
 <mrow>
  <msup>
   <mrow>
    <mi>sech</mi></mrow>
   <mn>2</mn>
  </msup>
  </mrow>
</math>

 envelope and the absence of high-frequency cutoff spectra) may generate signals in high-energy astrophysical events that differ from linear gravitational waves, providing a new target for future gravitational wave detection. This work establishes for the first time a strict generalized gauge transformation relationship between solitons, gravitons, optical solitons, and polarized photons, offering an exploratory paradigm for the unified theory of strong-field gravity and electromagnetism.
%K Gravitational Soliton
%K Einstein Equation
%K Gauge Transformation
%K Graviton
%K Dual Photon
%K Nonlinear Effects
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=142220