Fractal Ion Acoustic Waves of the Space-Time Fractional Three Dimensional KP Equation

Methods known as fractional subequation and sine-Gordon expansion (FSGE) are employed to acquire new exact solutions of some fractional partial di ﬀ erential equations emerging in plasma physics. Fractional operators are employed in the sense of conformable derivatives (CD). New exact solutions are constructed in terms of hyperbolic, rational, and trigonometric functions. Computational results indicate the power of the method.

Many important phenomena such as the effective behavior of the ionized matter, magnetic field near the surfaces of the sun and stars, emission mechanisms of pulsars, the origin of cosmic rays and radio sources, dynamics of magnetosphere, and propagation of electromagnetic radiation through the upper atmosphere required the study of plasma physics. Equations such as Korteweg de Vries (KdV), Burgers, KdV-Burgers, and Kadomtsev-Petviashvili (KP) were highly used models in the description of plasma systems.
We study the physical phenomena for space-time fractional KP equation with the aid of fractional calculus and examine the resulting solutions in detail. The factional calculus [7][8][9][10][11][12][13] has a wide range of applications and is deeply rotted in the field of probability, mathematical physics, differential equations, and so on. Very recently, fractional differential equations have got a lot of consideration as they define many complex phenomena in various fields. Several fractional-order models play very important roles in different areas including physics, engineering, mechanics and dynamical systems, signal and image processing, control theory, biology, and materials [14][15][16][17][18].
The paper is summarized as follows. Definitions and properties of conformable derivatives are discussed. In Section 2, a discussion about the two algorithms method, namely, fractional subequation method and sine-Gordon expansion method for solving FPDEs arising in plasma physics are given. In Section 3, two schemes are employed for some new exact solutions for the FKPE. We presented a graphical description of some of the solutions with a fixed value of fractal order α in a brief conclusion at the end of the article. Definition 1. Let ψ : ð0,∞Þ ⟶ R. Some definitions, useful properties, and a theorem about conformable derivatives are given as follows: If ψ is differentiable, then U α ðψÞðtÞ = t 1−α ðdψ/dhÞ.

Analysis of the Fractional Sine-Gordon Expansion (FSGE)
Method. Let us first consider the fractional sine-Gordon equation as m is constant.

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By using the transformation V = VðξÞ, ξ = aðx − νðt α /αÞÞ. Then Eq. (14) yields where C is an integration constant to be zero. Setting χðξÞ = Setting b = 1, we have In view of this method, we assume the trail solutions by Making use of Eq. (18), then Eq. (19) can be rewritten as follows where N can be obtained by balancing principle. Inserting Eq.

New Applications
In this part of our research, we apply a novel computational approach mentioned above to illustrate the advantages for finding analytical solutions of (3 + 1)-dimension space-time FKPE which is as follows where uðξÞ = Uðx, y, z, tÞ is the field function, ν, δ, d, and β∈ℝ. Let uðx, y, z, tÞ = UðξÞ, where ξ = kx + ct + ly + mz + ξ 0 , k, l, c, m, ξ 0 then Then, Eq. (22) reduces to Now, we assume the solution of Eq. (24) as where w = wðξÞ. Using the proposed algorithm for Eq. (24), we have M = 2. Then, Inserting (26) into (24) and collecting the terms with a similar degree of ðD α ξ wðξÞ/wðξÞÞ, equating it to zero, we have two values of a i , ði = 0, 1, 2::Þ, k, c, l, and m From Eqs. (28) and (26), we gain In view of Family 1-5 in (26), we obtain the following 3 Advances in Mathematical Physics Inserting Eq. (35) into (24) and the collecting the same power of cos i ðχðxiÞÞsin j ðχðxiÞÞ, admitting the system of algebraic equation, by solving them by Maple, admits to Set 1.
Inserting Set 1 into (35), we obtain the exact solution of Eq. (22) as where ξ = kx + ct + ly + mz + ξ 0 . Knowing Set 2 and Eq. (35), we gain the exact solution of Eq. (22) as follows: where ξ = kx + ct + ly + mz + ξ 0 . It is to be noted that, the 3D graph represent the obtained solutions with fixed y = z = 1 of Eqs. (38) and (40) are shown graphically (see Figures 1-7) for fixed parameter with a different choice of fractal order α.

Concluding Remarks
In this article, the extended fractional subequation method and sine-Gordon expansion (FSGE) method have been proposed for finding exact solutions of fractional partial differential equations (FPDEs) in the sense of conformable derivative. This paper studies (3 + 1)-dimensions spacetime FKPE which appears in plasma physics in the sense of conformable derivatives via two algorithms, namely, the extended fractional subequation method and FSGE method to obtain sets of exact solutions. Using suitable wave transform, the equations are reduced to some ODEs. Then, the admissible solutions are substituted into the resultant ODE. Equating the coefficients of ðD α ξ wðξÞ/wðξÞÞ in extended 5 Advances in Mathematical Physics fractional subequation method and cosine and sine functions and their multiplications in FSGE method to zero leads to some algebraic system of equations. Solving this system gives the relations among the parameters. Some 3-D solution graphs are presented in some finite domains to comprehend the effects of α.
The presence of parameters makes our results useful for the IVBVP with fractional order. For α = 1, our solutions go back to that previously obtained solution. The performance Advances in Mathematical Physics of these approaches shows the ability for applying on various space-time fractional nonlinear equations in nonlinear science.

Data Availability
No any data availability

Conflicts of Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.