smarandache curves in terms of sabban frame of fixed pole curve

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Bol. Soc. Paran. Mat. (3s.) v. 34 2 (2016): 5362. c SPM –ISSN-2175-1188 on line ISSN-00378712 in press SPM: www.spm.uem.br/bspm Smarandache Curves In Terms of Sabban Frame of Fixed Pole Curve Süleyman Şenyurt and Abdussamet Çalişkan abstract: In this paper, we study the special Smarandache curve in terms of Sabban frame of Fixed Pole curve and we give some characterization of Smarandache curves. Besides, we illustrate examples of our results. Key Words:Smarandache Curves, Sabban Frame, Geodesic Curvature, Fixed Pole Curve Contents 1 Introduction 53 2 Preliminaries 54 3 Smarandache Curves According to Sabban Frame of Fixed Pole Curve 55 3.1 CT C -Smarandache Curves ........................ 55 3.2 T C (C T C )-Smarandache Curves .................... 57 3.3 CT C (C T C )-Smarandache Curves ................... 58 3.4 Example .................................. 60 1. Introduction A regular curve in Minkowski space-time, whose position vector is composed by Frenet frame vectors on another regular curve, is called a Smarandache curve [12]. Special Smarandache curves have been studied by some authors . Ahmad T.Ali studied some special Smarandache curves in the Euclidean space.He stud- ied Frenet-Serret invariants of a special case [1]. M. Çetin , Y. Tunçer and K. Karacan investigated special smarandache curves according to Bishop frame in Euclidean 3-Space and they gave some differential goematric properties of Smaran- dache curves [5]. Şenyurt and Çalışkan investigated special Smarandache curves in terms of Sabban frame of spherical indicatrix curves and they gave some char- acterization of Smarandache curves, [3].Also, in their other work, when the unit Darboux vector of the partner curve of Mannheim curve were taken as the posi- tion vectors, the curvature and the torsion of Smarandache curve were calculated. These values were expressed depending upon the Mannheim curve, [4]. They de- fined NC-Smarandache curve, then they calculated the curvature and torsion of NB and TNB- Smarandache curves together with NC-Smarandache curve, [10]. Ö. 2000 Mathematics Subject Classification: 53A04. 53 Typeset by B S P M style. c Soc. Paran. de Mat.

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In this paper, we study the special Smarandache curve in terms ofSabban frame of Fixed Pole curve and we give some characterization of Smarandache curves. Besides, we illustrate examples of our results.

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Bol. Soc. Paran. Mat. (3s.) v. 342(2016): 5362.c SPMISSN-2175-1188online ISSN-00378712inpressSPM:www.spm.uem.br/bspmSmarandacheCurvesInTermsofSabbanFrameofFixedPoleCurveSleymanenyurtandAbdussametalikanabstract: Inthispaper, westudythespecial SmarandachecurveintermsofSabban frame of Fixed Pole curve and we give some characterization of Smarandachecurves. Besides,weillustrateexamplesofourresults.Key Words: Smarandache Curves, Sabban Frame, Geodesic Curvature, FixedPole CurveContents1 Introduction 532 Preliminaries 543 SmarandacheCurvesAccordingtoSabbanFrameofFixedPoleCurve 553.1 CTC-Smarandache Curves . . . . . . . . . . . . . . . . . . . . . . . . 553.2 TC(C TC)-Smarandache Curves. . . . . . . . . . . . . . . . . . . . 573.3 CTC(C TC)-Smarandache Curves. . . . . . . . . . . . . . . . . . . 583.4 Example. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601. IntroductionAregularcurveinMinkowski space-time, whosepositionvectoriscomposedbyFrenetframevectorsonanotherregularcurve,iscalledaSmarandachecurve[12]. Special Smarandachecurveshavebeenstudiedbysomeauthors. AhmadT.Ali studiedsomespecial SmarandachecurvesintheEuclideanspace.Hestud-iedFrenet-Serretinvariantsof aspecial case [1]. M. etin, Y. TunerandK.Karacaninvestigatedspecial smarandachecurves accordingtoBishopframeinEuclidean 3-Space and they gave some dierential goematric properties of Smaran-dachecurves [5]. enyurtandalkaninvestigatedspecial Smarandachecurvesintermsof Sabbanframeofspherical indicatrixcurves andtheygave somechar-acterizationofSmarandachecurves, [3].Also, intheirotherwork, whentheunitDarbouxvectorofthepartnercurveofMannheimcurveweretakenastheposi-tion vectors, the curvature and the torsion of Smarandache curve were calculated.Thesevalueswereexpressed dependingupontheMannheimcurve, [4]. Theyde-nedNC-Smarandachecurve, thentheycalculatedthecurvatureandtorsionofNB and TNB- Smarandache curves together with NC-Smarandache curve, [10]. .2000MathematicsSubjectClassication: 53A04.53TypesetbyBSPMstyle.c Soc. Paran. deMat.54 SleymanenyurtandAbdussametalikanBektaandS. Ycestudiedsomespecial smarandachecurvesaccordingtoDar-bouxFrameinE3[2]. M. TurgutandS. Ylmazstudiedaspecial caseof suchcurvesandcalleditsmarandacheTB2curvesinthespaceE41[12]. K.Tas.kpr, M. Tosun studied special Smarandache curves according to Sabban frame onS2[11].In this paper, the special smarandache curves such as CTC, TC(CTC), CTC(CTC) created by Sabban frame , {C, TC, C TC} , that belongs to xed pole of acurve are dened. Besides, we have found some results.2. PreliminariesThe Euclidean 3-spaceE3be inner product given by,= x21 +x32 +x23where (x1, x2, x3) E3. Let : I E3be a unit speed curve denote by {T, N, B}themovingFrenetframe. Foranarbitrarycurve E3, withrstandsecondcurvature, andrespectively, the Frenet formulae is given by[6]T= NN= T+BB= N.(2.1)Accordingly, the spherical indicatrix curves of Frenet vectors are (T), (N) and (B)respectively.These equations of curves are given by[7], [9]T(s) = T(s)N(s) = N(s)B(s) = B(s)(2.2)Let: I S2beaunitspeedspherical curve. Wedenotesasthearc-lengthparameter of. Let us denote by(s) = (s)t(s) = (s)d(s) = (s) t(s).(2.3)Wecall t(s) aunit tangent vector of. {, t, d}frame iscalled theSabban frameofonS2. Then we have the following spherical Frenet formulae of:= tt= +gdd= gt(2.4)where is called the geodesic curvature ofgonS2andg= t, d, [8]. (2.5)SmarandacheCurvesInTermsofSabbanFrameofFixedPoleCurve 553. SmarandacheCurvesAccordingtoSabbanFrameofFixedPoleCurveInthis section, weinvestigateSmarandachecurvesaccordingtotheSabbanframe of xed pole curve (C). LetC(s) =C(s)bea unitspeed regular sphericalcurves onS2.We denotesCas the arc-lenght parameter of xed pole curve(C)C(s) = C(s) (3.1)Dierentiating(3.1) , we havedCdsCdsCds= C(s)andTCdsCds= cos T sin B (3.2)From the equation (3.2)TC= cos T sinBandC TC= NFrom the equation (2.3)C(s) = C(s)TC(s) = cos T sin B(C TC)(s) = N(s)is called the Sabban frame of xed pole curve (C) .From the equation (2.5)g= TC, C TC = g= WThenfromtheequation(2.4)wehavethefollowingsphericalFrenetformulaeof(C):C= TCTC= C +W(C TC)(C TC)= WTC(3.3)3.1. CTC-SmarandacheCurvesDenition3.1. Let S2beaunit sphereinE3andsuppose that theunit speedregularcurveC(s)=C(s) lyingfullyonS2. Inthiscase, CTC- Smarandachecurvecanbedenedby(s) =12(C +TC). (3.4)56 SleymanenyurtandAbdussametalikanNow we can compute Sabban invariants ofCTC- Smarandache curves. Dier-entiating (3.4) , we haveTdsds=12

(cos sin )T+ WN (cos + sin )B

,wheredsds=

2 +

W

22. (3.5)Thus, the tangent vector of curveis to beT=1

2 +

W

2

(cos sin)T+ WN (cos + sin)B

. (3.6)Dierentiating(3.6), we getTdsds=1(2 + (W)2)32(1T+2N+3B) (3.7)where1= 2(sin + cos )

2W+

W

3

W2(sin + cos ) W

W

(cos sin)2=

2 +

W

2

(cos sin) +(cos + sin )

+ 2

W

3= W

2 +

W

2

2(cos sin ) W2(cos sin)+W

W

(cos + sin).Substituting the equation (3.5) into equation (3.7) , we reachT=2

2 +

W

22(1T+2N+ 3B). (3.8)Considering the equations (3.4) and (3.6) , it easily seen that(C TC)=1

4 + 2

W

2

W(cos sin )T+ (3.9)+2N+ (W(cos + sin ))B

SmarandacheCurvesInTermsofSabbanFrameofFixedPoleCurve 57From the equation (3.8) and (3.9) , the geodesic curvature of(s) isg= T, (C TC)

=1

2+

W

232

W(cos sin )1 + 22 +W(cos + sin )3

.3.2. TC(C TC)-SmarandacheCurvesDenition3.2. LetS2beaunitsphereinE3andsupposethattheunitspeedreg-ularcurveC(s) = C(s)lyingfullyonS2. Inthiscase,TC(CTC)-Smarandachecurvecanbedenedby(s) =12(TC+C TC). (3.10)Now we can compute Sabban invariants of TC(C TC) - Smarandache curves.Dierentiating(3.10), we haveTdsds=12

(sin Wcos )T+ WN+ (Wsin cos )B

wheredsds=

1 + 2

W

22. (3.11)In that case, the tangent vector of curveis as followsT=1

1 + 2

W

2

(sin Wcos )T+ (3.12)+WN+ (Wsin cos )B

Dierentiating(3.12), it is obtained thatTdsds=1

1 + 2

W

2

32(1T+2N+3B) (3.13)where58 SleymanenyurtandAbdussametalikan1= cos +W(sin + 2Wcos + 2

W

2sin 2W23)

W

(cos 2Wsin )2= (sin Wcos + 2

W

2(sin Wcos ))(W(sin cos ) 2

W

3(sin cos )) +

W

3= sin +W(+cos + 2

W

2+ 2

W

2cos + 2W sin) +

W

(sin + 2Wcos ).Substituting the equation (3.11) into equation (3.13) , we getT=2

1 + 2

W

22(1T+2N+3B) (3.14)Using the equations (3.10) and (3.12) , we easily nd(C TC)=1

2 + 4

W

2

(2Wsin cos )T+ (3.15)+N+ (2Wcos + sin)B

So, the geodesic curvature of(s) is as followsg= T, (C TC)

=1

1+2

W

232((2Wsin cos )1 +2 + (2Wcos + sin )3).3.3. CTC(C TC)-SmarandacheCurvesDenition 3.3. Let S2bea unit sphereinE3and supposethatthe unit speed regu-larcurve C(s) = C(s)lyingfullyon S2. In this case,CTC(CTC)- Smarandachecurvecanbedenedby(s) =13(C +TC+C TC). (3.16)SmarandacheCurvesInTermsofSabbanFrameofFixedPoleCurve 59Let us calculate Sabbaninvariants of CTC(C TC) - Smarandachecurves.Dierentiating(3.16), we haveTdsds=13

(cos sin Wcos )T++WN+ (sin cos + Wsin)B

wheredsds=

2(1 W+

W

2)3. (3.17)Thus, the tangent vector of curveisT=1

2

1 W+

W

2

(cos sin Wcos )T (3.18)+WN+ (sin cos + Wsin )B

Dierentiating(3.18), it is obtained thatTdsds=122

1 W+

W

2

32(1T+2N+3B) (3.19)where1=

1 W+

W

2

2(sin + cos ) + 2W sin 2W

+W(cos sin ) + 2

W

(cos +Wsin)2=

1 W+

W

2

2

cos sin Wcos

+2

sin + cos Wcos

+ 2

W

1 W

+

W

23=

1 W+

W

2

2W+ 2(sin cos ) + 2W cos

+

W

2sin + 2

W

(sin +Wcos ) W(sin + cos ).Substituting the equation (3.17) into equation (3.19) , we reachT=34

1 W+

W

2

2(1T+2N+3B). (3.20)60 SleymanenyurtandAbdussametalikanUsing the equations (3.16) and (3.18) , we have(C TC)=16

1 W+

W

2

(2Wsin Wcos (3.21)cos )T+ (1 W)N+ (sin + 2Wcos +Wsin )B

From the equation (3.20) and (3.21), the geodesic curvature of(s) isg= T, (C TC) =142(1 W+ (W)2)32[1(2Wsin Wcos cos ) +2(1 W) +3(sin + 2Wcos + Wsin)].3.4. ExampleLet us consider the unit speed spherical curve:(s) = {9208 sin16s 1117 sin 36s, 9208 cos 16s +1117 cos 36s,665 sin 10s}.It is rendered in Figure 1.Figure 1: FixedPolecurve(T)In terms of denitions, we obtain Smarandache curves according to Sabban frameonS2, see Figures 2 - 4.SmarandacheCurvesInTermsofSabbanFrameofFixedPoleCurve 61Figure 2: CTC- Smarandache CurveFigure 3: TC(C TC) - Smarandache CurveFigure 4: CTC(C TC) - Smarandache Curve62 SleymanenyurtandAbdussametalikanReferences1. Ali A. T., Special Smarandache Curves inthe EuclideanSpace, International Journal ofMathematicalCombinatorics,Vol.2,pp.30-36,2010.2. Bekta. andYceS., Special Smarandache Curves According toDarbouxFrameinEu-clidean3- Space,RomanianJournal of MathematicsandComputerScience, Vol.3, Issue1,pp.48-59,2013.3. alkanA. andenyurt, S., SmarandacheCurvesInTermsof SabbanFrameof SphericalIndicatrixCurves,Gen.Math.Notes,inpress,2015.4. alkanA.andenyurt, S., NCSmarandacheCurvesof MannheimCurveCoupleAc-cordingtoFrenet Frame, International Journal of Mathematical Combinatorics, Vol:1, pp.13-15,2015.5. etinM., TunerY. andKaracanM. K., SmarandacheCurvesAccordingtoBishopFrameinEuclidean3-Space,Gen.Math.Notes,Vol.20,pp.50-66,2014.6. DoCarmo, M.P., Dierential Geometryof CurvesandSurfaces, PrenticeHall,EnglewoodClis, NJ,1976.7. Hacsaliholu H.H.,Dierantial Geometry,AcademicPressInc.Ankara,1994.8. KoenderinkJ.,SolidShape,MIT Press,Cambridge,MA,1990.9. ONeill B.,ElemantaryDierential Geometry,AcademicPressInc.NewYork,1966.10. SenyurtS.andSivasS.,AnApplicationof SmarandacheCurve,UniversityofOrdujournalofscienceandtechnology,Vol:3(1),pp.46-60,2013.11. TakprK.andTosunM.,SmarandacheCurvesonS2,BoletimdaSociedadeParanaensedeMatemtica3Srie.Vol.32,no:1,pp.51-59,2014.12. TurgutM. andYlmazS., SmarandacheCurvesinMinkowski Space-time, International J.Math.Combin.,Vol.3,pp.51-55,2008.Sleymanenyurt(Correspondingauthor)Facultyof ArtsandSciences,Departmentof Mathematics,OrduUniversity,52000, Ordu/TurkeyE-mail address: [email protected] alikanFacultyof ArtsandSciences,Departmentof Mathematics,OrduUniversity,52000, Ordu/TurkeyE-mail address: [email protected]