Fermi-Walker derivative and biharmonic particle play an important role in skillful applications. We obtain a new characterization on binormal spherical indicatrix by using the Fermi-Walker derivative and parallelism in space. We suggest that an inextensible flow is the necessary and sufficient condition for this particle. Finally, we give some characterizations for a non-rotating frame of this binormal spherical indicatrix.
In the literature there are many studies on Fermi-Walker transport and Fermi-Walker derivative. Simple description for the construction of Fermi-Walker transported frames out of an arbitrary set of tetrad fields was presented in Ref. [1, 2, 3].
Recently, a research on Fermi-Walker transports has been expanded to Minkowski spacetime in Ref. [4, 5]. Frenet-Serret equations constructed by Synge on world lines are a strong instrument for studying motion of non-zero rest mass for test particles in an assumed gravitational field [6, 7, 8, 9, 10, 11]. Also, Frenet-Serret equations have been generalized from non-null to null trajectories in a spacetime by using a new formalism with Fermi-Walker transport in Ref. .
In Ref. [5, 10, 11, 12, 13, 14, 15, 16], some curves corresponding to their flows has been investigated. A new characterization of inextensible flows for curves with Fermi-Walker derivative and its parallelism on the 3-dimensional space has also been constructed. More precisely, they have constructed new figures as illustrations of the moving charged particle in electromagnetic field. Flows of curves of a given curve are also widely studied in Ref. [17, 18]. Some characterizations of curves and surfaces are given in Ref. [19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29].
In Ref. , Fermi-Walker derivative, Fermi–Walker parallelism, non-rotating frame, Fermi-Walker terms with Darboux vector are given in Minkowski 3- dimensional space. In Ref. , flows of biharmonic particles on a new spacetime are defined by using Bianchi type-I (B-I) cosmological model. A geometrical description of timelike biharmonic particle in spacetime is also given. In Ref. , a new method for inextensible flows of timelike curves in a conformally flat, quasi conformally flat and conformally symmetric 4-dimensional LP-Sasakian manifold is developed.
The structure of the paper is as follows. First, we construct a new characterization for inextensible flows of binormal spherical indicatrix and Fermi-Walker parallelism by using Fermi-Walker derivative in space. Finally, we give some characterizations for non-rotating frame of binormal spherical image.
In this section, we study relationship between the Fermi-Walker derivative and the Frenet fields of curves. Moreover, we obtain some characterizations and an example of the curve.
Fermi transport and derivative have the following theories.
Fermi-Walker transport is defined by
is called Fermi-Walker derivative of V with respect to T along the curve in space.
With this definition the following features are satisfied :
If the curve is a geodesic, then the Fermi-Walker transport is identical to parallel transport: if ∇TT = 0, then = ∇TV.
= 0, that is, the tangent to the curve is always Fermi-Walker transported.
V and W are Fermi-Walker transported vector fields, their inner product remains constant along the curve
is attained, .
Physical sense of above attribute is that V is orthogonal to T along curve. Thus, horizontal change in it along the curve can only stem from rotation of the vector in a plane perpendicular to T. Property of Fermi-Walker transport = 0 intends that vector is moved without any rotation. This is fundamental to detect the action of gyroscopes when moved with accelerated observers.
3 Construction of Fermi-Walker derivative for inextensible flows of curves
Let α : I ⊂ R → 𝕄 be a curve in space and V be a vector field along the curve α. For a map Γ : I × (–ε, ε )→ 𝕄, putting Γ (s, 0) = α (s),
Therefore, the following functions can be obtained:
Speed function v(s, t) =
Curvature function κ (s, t) of αt(s),
Torsion function τ (s, t) of αt(s).
The variations of those functions at t = 0 are
where R is the curvature tensor.
Second, a flow of αt(s) may be represented as
where β1, β2, β3 are smooth functions.
On the other hand, Körpınar–Turhan obtained flows of binormal spherical images of curves in space .
Now, we investigate conditions of Frenet vectors.
Ifϕis binormal spherical indicatrix ofα, then
Theorem 3.3 (Main Theorem)
By using the definition of Fermi-Walker transport we have the above equality. This completes the proof.
From Serret-Frenet formulas and Fermi-Walker derivative, we have
Using flow of Tϕ, we obtain
Since the above equation, we get
By using the properties of cross product we can easily write that
Then it is easy to obtain that
which completes the proof.
This can be verified using an argument similar to above theorem.
This can be verified using an argument similar to above theorem.
Using above theorems, we get the following corollaries by straight-forward computations.
If ∇tTϕalong the curve, parallel to the Fermi–Walker terms, then
If ∇tNϕalong the curve, parallel to the Fermi–Walker terms, then
If ∇tBϕalong the curve, parallel to the Fermi–Walker terms, then
4 Applications to electrodynamics
In this section, we construct the Fermi–Walker derivative in the motion of a charged particle under the action of only electric or magnetic fields.
The equation of motion of a charged particle of mass m and electric charge q under the electric field 𝓔 and magnetic field 𝓑 is given by the Lorentz equation. In Gaussian system of units, we have :
Only a magnetic induction 𝓑 (no electric field 𝓔), the equation of motion is(26)
From above equation and Frenet frame, we easily choose(27)
Therefore, we can write(29)
which implies that(30)(31)(32)
On the other hand, we obtain(33)
If ∇t𝓑 along the curve, parallel to the Fermi–Walker terms, then(34)(35)(36)
Only an electric induction 𝓔 (no magnetic field 𝓑), the equation of motion is(37)
Then, we easily have(38)
which implies that(39)Figure 1(40)
On the other hand, we obtain(41)
If ∇t𝓔 along the curve, parallel to the Fermi–Walker terms, then(42)(43)(44)
5 Some pictures
In this section we draw some pictures corresponding to different cases by using a following example:
The time helix is parametrized by
where A, B are functions of time only.
Fermi-Walker transport and inextensible flows play an important role in geometric design and theorical physics.
In this paper, we have studied Fermi-Walker derivative and Fermi–Walker parallelism for binormal indicatrix. The aim of this work is to show inextensible flows of Fermi-Walker derivative by using curvatures of curves.
Furthermore, using the Frenet frame of the given curve, we present some partial differential equations. We have given some illustrations together with some examples, which we have used flows of Frenet frame and Fermi derivative in space. Finally, we construct the Fermi–Walker derivative in the motion of a charged particle.
In our future work under this theme, we propose to study the conditions on the Fermi-Walker derivative and Fermi-Walker parallelism for spherical indicatrix in Minkowski space.
 Fermi E., Sopra i fenomeni che avvengono in vicinanza di una linea oraria, Atti Accad. Naz. Lincei Cl. Sci. Fiz. Mat. Nat., 1922, 31, 184–306.Search in Google Scholar
 Körpınar T., On the Fermi Walker Derivative for Inextensible Flows, Zeitschrift für Naturforschung A- A Journal of Physical Sciences., 2015, 70a, 477-482.10.1515/zna-2015-0044Search in Google Scholar
 Synge J.L., Relativity, The General Theory. North Holland, Amsterdam, 1960.Search in Google Scholar
 Bossavit A., Differential forms and the computation of fields and forces in electromagnetism, Euro.J. Mech.B/Fluids, 1991, 10, 474-488.Search in Google Scholar
 Einstein A., Relativity, The Special and General Theory, New York: Henry Holt, 1920.Search in Google Scholar
 Jiang G. Y., 2-harmonic maps and their first and second variational formulas, Chinese Ann. Math. Ser. A, 1986, 7, 389–402.Search in Google Scholar
 Pina E., Lorentz transformation and the motion of a charge in a constant electromagnetic field, Rev. Mex. Fis., 1967, 16, 233-236.Search in Google Scholar
 Körpınar T., Bianchi Type-I Cosmological Models for Inextensible Flows of Biharmonic Particles by Using Curvature Tensor Field in Spacetime, Int J Theor Phys., 2015, 54, 1762-1770.10.1007/s10773-014-2379-zSearch in Google Scholar
 Körpınar T., Turhan E., Time Evolution Equations for Surfaces Generated via Binormal Spherical Image in Terms of Inextensible Flows, Journal of Dynamical Systems and Geometric Theories., 2014, 12, 145-157.10.1080/1726037X.2014.979711Search in Google Scholar
 Körpınar T., A new method for inextensible flows of timelike curves in 4-dimensional LP-Sasakian manifolds, Asian-European Journal of Mathematics, 2015, 8, 10.1142/S1793557115500734.Search in Google Scholar
 Gray A., Modern Differential Geometry of Curves and Surfaces with Mathematica, CRC Press, 1998.Search in Google Scholar
 Körpınar T., Turhan, E., Asil, V., Tangent Bishop spherical images of a biharmonic B-slant helix in the Heisenberg group Heis3, Iranian Journal of Science and Technology Transaction A: Science, 2012, 35, 265-271.Search in Google Scholar
 Körpınar T., Turhan E., Time-Tangent Surfaces Around Biharmonic Particles and Its Lorentz Transformations in Heisenberg Spacetime, Int. J. Theor. Phys., 2013, 52, 4427-4438.10.1007/s10773-013-1761-6Search in Google Scholar
 O’Neill B., Semi-Riemannian Geometry, Academic Press, New York, 1983.Search in Google Scholar
 Synge J.L., Time-like helices in flat spacetime. Proc. R. Ir. Acad., Sect. A, 1967, 65, 27-41.Search in Google Scholar
 Turhan E., Körpınar T., On Characterization Of Timelike Horizontal Biharmonic Curves In The Lorentzian Heisenberg Group Heis3, Zeitschrift für Naturforschung A- A Journal of Physical Sciences, 2010, 65a, 641-648.10.1515/zna-2010-8-904Search in Google Scholar
© 2018 G. A. Suroğlu, published by De Gruyter
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.