International Journal of Scientific & Engineering Research, Volume 5, Issue 12, December-2014 1254
ISSN 2229-5518
Advanced q-Bessel Function of Two
Variables
Dr. Abha Tenguria, Ritu Sharma
Abstract :- The main object of this paper to construct q-Bessel functions of two variables of first kind and found various results of J r,s (x, y ; q) like generating function, recurrence relation. Furthermore we use q-analogue to find some new significant results and generalizations have been discovered.
—————————— ——————————
(a; q)n = �
1 n = 0
n−1
J
The problem of Mathematical Physics leads us to
determine the solutions of Differential Equations which satisfy certain prescribed conditions. Many special
(2)
�{(1 − aq )}
J=O
∞
for nϵN
functions have been exposed to current generalizations to a
base of q, which are usually noted as q –special function. Basic analogise of Bessel functions have been introduced by Jackson [4] and Swarthow[9].
we know that [1]the ordinary cylindrical Bessel functions, define q-generalization of power series expansions. Three
different types of such q-expansion can be recognized, each
(a; q)∞ = �{(1 − aqJ)}
J=O
(a; q)0 = 1
The q-factorial [n]q ! being defined as, where n is integer
(3)
of them satisfy recurrence relations, second order q- differential equation and addition theorems, which reduce to those holding for the usual Bessel function in the limit q
→ 1.This paper presents new form of Bessel function with q
–analogues of one and two variables.
Where 0 < q < 1.
[n]q ! =
(q; q)n
n2
q 2
The Bessel’s function of first kind of order r is defined by [7]
(4)
∞
m
Jr (x) = �
x 2m+r
� �
Before entering the specific topic of the paper, let us briefly
review the properties of q – Bessel functions. We discuss
m=0
! m Γr + m + 1 2
Definitions and Notations of q-analogy.
The q – shifted factorial Notation of Real and Complex
————————————————
• Dr. Abha Tenguria is Professor In Govt. Maharani Laxmi Bai Girls' P.G.
The generalized q-Bessel function of one variable is defined by [1]
(5)
∞
(Autonomous) College Bhopal (M.P.), India.
(−1)m
x 2m+r
• Jr (x; q) = � [m]
[ r + m ] ! �2
• Ritu Sharma is Research Scholar In Atal Bihari Vajpayee Hindi
Vishwavidyalaya Bhopal (M.P.) , India
number is given by [1].
When q → 1, (4)
m=0 q ! q
(1)
And Two variable Bessel’s functions are defined by [7] with
r and s are integer we have the representations
IJSER © 2014 http://www.ijser.org
International Journal of Scientific & Engineering Research, Volume 5, Issue 12, December-2014 1255
ISSN 2229-5518
(6)
s
x
Eq ��
1
�t − � +
yρ(x)
�w −
1
���
x r y ρ(x)
2� 2 � x2
2 t 2 w
Jr,s (x, y) =
0F1 �−; r + 1; − � 0F1 �−; s
Γr + 1 Γs + 1 4
y2 ρ2(x)
for t ≠ 0, w ≠ 0 and t,w ∈ ℂ .
or
Jr,s (x, y)
∞
+ 1; − �
4
(−1)m+n
x 2m+r
�
y ρ(x) 2n+s
� �
cases of the q- exponential function
(8)
∞
xr
Eq (x) = � [r] !
r=0 q
and
= �
m,n=0
�
! n ! m Γr + m + 1 Γs + n + 1 2 2
(9)
In this paper we have to prove that q-Bessel function of two
variable generating functions, recurrence relation and some
∞
Eq (x) = �
qr �2 xr
〈q; q〉
results of
r=0 r
|x| < 1 .
∞ (−1)m+n �x�2m+r �yρ(x)
2n+s
Consequently in the limitq → 1, we have limq→1�Eq (1 −
2 2 �
q)z� = ez
by [2]
Jr,s (x, y ; q) = �
[m + r] ! [m] ! [n + s] ! [n] !
m,n=0 q q q q
Using the formula (8), we get L.H.S.
x
When q → 1 Eq ��
2
1
�t − t � +
yρ(x)
2
�w −
1
w���
xt x
yρ(x)w
yρ(x)
= Eq �� 2 �� Eq ��− 2t�� Eq ��
2 �� Eq ��−
2w ��
variable Jr,s (x , y ; q) , we defined by
∞ ∞ �xt�
x m ∞
∞ �yρ(x)w
yρ(x) n
= � � 2 �– 2t�
2 � �–
� �
2w �
(7)
r=0 m=0
[r]q! [m]q !
s=0 n=0
[s]q ! [n]q !
∞ (−1)m+n �x�2m+r �yρ(x)�
If we replace r by m+ r & s by n + s, then we get following
2 2
Jr,s (x , y ; q) = �
[m + r] ! [m] ! [n + s] ! [n] !
equation
m,n=0 q q q q
m+r
∞ ∞ (−1)m � �
� x � ∞
∞ (−1)n �
yρ(x)w n+s
�
yρ(x) n
� �
= � � 2 2t � �
[m + r]q! [m]q !
2 2w
[n + s]q ! [n]q !
Jr,s (x , y ; q)
s
r=−∞ m=0
s=−∞ n=0
�x�r �yρ(x)�
2 2 2
∞ ∞ m+n
x m+r+m
yρ(x) n+s+n
n+s−n
m+r−m
= 2 2
−x
oF �−; [m] !; � oF
−y ρ(x)
�−; [n] !; �
(−1)
�2�
� 2 �
(w)
(t)
[r]q ! [s]q ! 1
q 4 1 q 4
= � �
[m + r] ! [m] ! [n + s] ! [n] !
Now we will deduce the generating function of the
r,s=−∞ m,n=0
q q q
q
2n+s
advanced q-Bessel function of two variables Jr,s(x,y;q).
∞ ∞ (−1)m+n �x�2m+r �yρ(x)�
= � t r ws � 2 2
Theorem 3.1 :- Prove that Jr,s (x,y;q) is the coefficient of t rws
in the expansion of
(10)
r,s=−∞
m,n=0
[m + r]q ! [m]q ! [n + s]q ! [n]q !
IJSER © 2014 http://www.ijser.org
International Journal of Scientific & Engineering Research, Volume 5, Issue 12, December-2014 1256
ISSN 2229-5518
x
Eq ��
1
�t − � +
yρ(x)
�w −
∞
1
��� = � t rws Jr,s (x , y ; q)
(14)
2 t 2
w
r,s=−∞
Γ q(n + 1) = [n]q!
Which is a generating function of Jr,s (x , y ; q) .If using (9)
then we get result.
∞
1
= lim �
2m+r
(−1)m+n(1 − q)2m(1 − q)2n � �
2
�yρ(x)�
2
q→1 [r]q! [s]q!
m,n=0
(q; q)m (qr+1; q)m(qs+1 ; q)n (q; q)n
(11)
x 1 yρ(x) 1
Taking limit q → 1 and we obtain
2n+s
Eq ��
2
�t −
t � +
2 �w −
∞
w���
1 ∞ (−1)m+n �x�
= �
2m+r
yρ(x)
� 2 �
r2 +s2
= q 2 � Jr,s (x , y ∶ t , w ; q)
r,s=−∞
[r]![s]!
m,n=0
(1)m (r + 1)m (s + 1)n (1)n
Theorem3.2 The function Jr,s (x , y ; q) is q –analogy of each
of the Bessel function an
∞ (−1)m+n �x�2m+r �yρ(x)�
1 2 2
= �
limq→1 Jr,s �(1 − q)x , (1 − q)y ; q� = Jr,s (x, y).
[r]! [s]!
m,n=0
Γm + 1 Γn + 1 Γr + m + 1 Γs + n + 1
∞
(−1)m+n
x 2m+r
�
y ρ(x) 2n+s
� �
presented the q-exponential function, they say (12)
[n] = (q; q)n
q ! (1 − q)n
[n + k] = (q; q)n+k
q ! (1 − q)n+k
Where 0 < q < 1.
= �
m,n=0
�
! n ! m Γr + m + 1 Γs + n + 1 2 2
Hence, we get
(15)
lim Jr,s �(1 − q)x , (1 − q)y ; q� = Jr,s (x, y)
q→1
Using the relation by Gasper [8]
(13)
(q; q)n+k = (q; q)k (qk+1 ; q)n
lim Jr,s�(1 − q)x , (1 − q)y ; q�
q→1
2m+r
yρ(x) 2n+s
Lemma 4.1:-If r ,s be integer then Jr,s (x , y ; q)
satisfies
∞
= lim �
q→1
m,n=0
(−1)m+n(1 − q)m+r(1 − q)n(1 − q)m (1 − q)n+s �x �
2
(q; q)m+r (q; q)m(q; q)n+s(q; q)n
� 2 �
(16)
J−r,s
(x , y ; q) = (−1)r Jr,s
(x , y ; q)
Using the relation (13), we obtain
∞ (−1)m+n �x�2m+r �yρ(x)�
2m+r
yρ(x) 2n+s
2 2
Jr,s (x , y ; q) = �
∞
= lim �
(−1)m+n (1 − q)2m (1 − q)2n (1 − q)r (1 − q)s �x �
2
� 2 �
m,n=0
[m + r]q ! [m]q ! [n + s]q ! [n]q !
q→1
m,n=0
(q; q)m (q; q)r (qr+1; q)m(qs+1 ; q)n (q; q)s (q; q)n
Here Substitute r → -r and we get
2m+r
yρ(x) 2n+s
= lim
(1 − q)r (1 − q)s
�
(−1)m+n (1 − q)2m (1 − q)2n �x�
2
� 2 �
q→1
(q; q)r (q; q)s
m,n=0
(q; q)m (qr+1 ; q)m (qs+1; q)n (q; q)n
2m−r
∞ m+n
2
yρ(x)
2 �
2n+s
We know that by relation of q-gamma function with q-
factorial function
J−r,s (x , y ; q) = � [m − r] ! [m] ! [n + s] ! [n] !
m,n=0 q q q q
IJSER © 2014
International Journal of Scientific & Engineering Research, Volume 5, Issue 12, December-2014 1257
ISSN 2229-5518
Replace m by r +k then we obtain
Then Result is Obtain
2n+s r s
∞ (−1)r+k+n �x�2k+r �yρ(x)
= � 2 2
J−r,−s (x , y ; q) = (−1) Jr,−s(x , y ; q) = (−1) Jr,−s (x , y ; q)
= (−1)r+s Jr,s (x , y ; q)
k,n=0
[k + r]q ! [k]q ! [n + s]q ! [n]q !
∞ (−1)k+n �x�2k+r �yρ(x)�
Lemma 4.4:- The function Jr,s (x , y ; q)satisfies the relation
(19)
r
= (−1)r � 2 2
Jr,s (−x , y ; q) = (−1)
Jr,s (x , y ; q)
k,n=0
[k + r]q! [k]q ! [n + s]q ! [n]q !
and hence it is even (or odd) function if the integer n is even
(or odd).
= (−1)rJr,s (x , y ; q)
Which is the recurrence relation then we have the following
lemma (16)
∞
(−1)m+n �x�2m+r �yρ(x)
2n+s
2 2 �
J−r,s (x , y ; q) = (−1)r Jr,s (x , y ; q)
Jr,s (x, y ; q) = �
[m + r] ! [m] ! [n + s] ! [n] !
Lemma 4.2:-If r, s be integer then Jr,s (x , y ; q) satisfies
(17)
m,n=0 q q
for x=-x, then we get
q q
2n+s
∞ (−1)m+n �−x 2m+r �yρ(x)
Jr,−s (x , y ; q) = (−1)s Jr,s (x , y ; q)
J (−x, y ; q) = �
2 � 2 �
Substitute s→ -s and we get
Then
r,s
m,n=0
[m + r]q ! [m]q ! [n + s]q ! [n]q !
2m+r
∞ (−1)m+n � �
�yρ(x)
2n−s
∞ (−1)m+n �x�
2m+r
yρ(x)
�
2n+s
2 2 �
2m+r � 2 2
Jr,−s (x , y ; q) = �
[m − r] ! [m] ! [n − s] ! [n] !
Jr,s (x, y ; q) = (−1)
[m + r] ! [m] ! [n + s] ! [n] !
m,n=0 q q q q
m,n=0 q q q q
Replace n by s+ t then we get
∞ (−1)m+s+t �x�2k+r �yρ(x)�
For all value of m is positive(−1)2m = 1
= � 2 2
Then
t,n=0
[k + r]q ! [k]q ! [t]q! [s + t]q !
∞ (−1)m+n �x�2m+r �yρ(x)�
∞ (−1)m+t �x�2k+r �yρ(x)
2s+t
2 2
Jr,s (x, y ; q) = (−1)r �
= (−1)s �
2 2 �
m,n=0
[m + r]q ! [m]q ! [n + s]q ! [n]q !
t,n=0
[k + r]q! [k]q ! [t]q! [s + t]q !
Hence the recurrence relation is
Jr,−s (x , y ; q) = (−1)s Jr,s (x , y ; q)
Which is the prove of recurrence relation (17).
Lemma 4.3:-If r ,s be integer then Jr,s (x , y ; q) satisfies
(18)
J−r,−s (x , y ; q) = (−1)rJr,−s(x , y ; q) = (−1)s Jr,−s (x , y ; q)
= (−1)r+s Jr,s (x , y ; q)
(−x , y ; q) = (−1)rJr,s (x , y ; q)
r,s
Lemma 4.5:- The function Jr,s (x , y ; q)satisfies the relation
(20)
Jr,s (x , −y ; q) = (−1)s Jr,s (x , y ; q)
and hence it is even (or odd) function if the integer n is even
(or odd).
Now, if we substitute y by –y in the relation (7) , then we get the result.
IJSER © 2014 http://www.ijser.org
International Journal of Scientific & Engineering Research, Volume 5, Issue 12, December-2014 1258
ISSN 2229-5518
Lemma 4.6:- The function Jr,s (x , y ; q)satisfies the relation
(21)
Jr,s (−x , −y ; q) = (−1)r+s Jr,s (x , y ; q)
And hence it is even (or odd) function if the integer n is
even (or odd).
Now, if we substitute x by –x (same as above) & y by –y in
the relation (7) , then we get the result.
[1] Giuseppe Dattoli-Amalia Torre, ’Symmetric Q-Bessel Functions’, Le Matematiche, Vol. LI Sept. (1996)-Fasc I, pp. 153-167.
[2] Mansour Mahmoud, ‘Generalized q-Bessel function and its properties’ Advances in Difference Equations 2013, 2013:121.
[3] Math J., The zeros of basic Bessel functions, the functions Jν+ax(x),
and associated orthogonal polynomials, Anal. Appl. 86 (1982), no. 1, 1–
19.
[4] Jackson F. H., on generalized functions of Legendre and Bessel, Trans. Roy. Soc. Edin. 41 (1904), 1–28.
[5] Floreanini R., Letourneux J., Vinet L.: More on the q-oscillator algebra and q-orthogonal polynomials. J. Phys. A, Math. Gen. 28, L287- L293 (1995)
[6] Exton H. q-Hypergeometric Functions and Applications. Ellis
Horwood, Chichester (1983)
[7] Rabia Aktas, Abdullah Altin, Bayram Cekim : On a Two –Variable Analogue Of The Bessel Functions. J. of Inequalities And Special Functions Issn: 2217-4303, vol-3(2012)pages 13-23
[8] Gasper G., Rahman M.: Basic Hypergeometric Series, 2nd edn. Cambridge University Press, Cambridge (2004).
[9] Swarthow R.F., An addition Theorem And Some Product Formulas For The Hahn-Exton q –Bessel Function , Can . J. Math 44(1992), PP.867-879.
[10] Anderson G.D, Vamanamurthy M.K., Vuorinen M.: Special functions of quasiconformal theory, Exposition Math. 7(1989) 97–136.
[11] Watson G.N., A Treatise on the Theory of Bessel Functions, 2nd
Edition, Cambridge University Press, 1944.
[12] Abramowitz M., Stegun (Eds.) I.A., Handbook of Mathematical
Functions, 10th Edition, Dover Publications, Inc., New York, 1972.
[13] Jackson F. H., On generalized functions of Legendre and Bessel. Transactions of the Royal Society of Edinburgh, 41:l-28(1904).
IJSER © 2014 http://www.ijser.org