1. Introduction
The Hardy discrete inequality is known as (see [
1]):
where
.
In [
2], Hardy exemplified the continuous version of
by utilizing the calculus of variations, which has the form:
where
, which is integrable over
is a convergent and integrable function over
and
is a sharp constant in
and
In [
3,
4], Copson outreached the inequalities of Hardy
and
Particularly, he exemplified that if
then:
and if
then
The continuous transcriptions of
and
were exemplified by Copson in [
4]. Particularly, he exemplified that if
then:
where
then
where
.
Leindler in [
5] and Bennett in [
6] obtains some generalizations of
and
by using new weighted function. Specially, Leindler exemplified that if
then:
Bennett explicated that if
then:
Bennett in [
7,
8] established a converses of the inequalities
and
Particularly, he exemplified that if
then:
and if
then
where
In the last decades, the study of the dynamic equations and inequalities on time scales became a main field in applied and pure mathematics. We refer to the papers [
9,
10,
11,
12,
13,
14,
15]. In fact, Refs. [
16,
17,
18,
19,
20,
21,
22,
23,
24] mentions forms of the above inequalities on a time-scale and their extensions.
For example, in [
25], Saker et al. exemplified the time scale version of a converse of the inequalities
and
, respectively, as follows:
Assume that
be a time scale with
then
If
, then
where
In the same paper [
25], Saker et al. proved the time scale transcript of the Bennet-Leindler inequalities
and
, respectively, as follows: Assume that
is a time scale with
.
then:
If
, such that
and
, then
In recent years, a lot of work has been published on fractional inequalities and the subject has become an active field of research with several authors interested in proving the inequalities of fractional type by using the Riemann-Liouville and Caputo derivative (see [
26,
27,
28]).
On the other hand, the authors in [
29,
30] introduced a new fractional calculus called the conformable calculus and gave a new definition of the derivative with the base properties of the calculus based on the new definition of derivative and integrals.
The main question that arises now is: Is it possible to prove new fractional inequalities on timescales and give a unified approach of such studies? This in fact needs a new fractional calculus on timescales. Very recently Torres and others, in [
31,
32], combined a time scale calculus and conformable calculus and obtained the new fractional calculus on timescales. Thus, it is natural to look on new fractional inequalities on timescales and give an affirmative answer to the above question.
In particular, in this paper, we will prove the fractional forms of the classical Hardy, Copson type and its reversed and Leindler inequalities with employing conformable calculus on time scales. The article is structured as follows:
Section 2 is an introduction of the basics of fractional calculus on timescales and
Section 3 contains the main results.
2. Basic Concepts
In this part, we introduce the essentials of conformable fractional integral and derivative of order
on time scales that will be used in this article (see [
33,
34,
35]). A time scale
is an arbitrary nonempty closed subset of the real numbers
. We define the operator
, as
. In addition, we define the function
by
Finally, for any
, we refer to the notation
.
In the following, we define conformable -fractional derivative and -fractional integral on .
Definition 1 (
Definition 1, [
31])
. Suppose that Then for ,
we define to be the number with the property that, for any ,
there is a neighborhood V of s.t., we have: The conformable
-fractional derivative on
at 0 as:
Theorem 1 (
Theorem 51, [
31])
. Assume be conformable -
fractional derivative on , then- (i)
The
is conformable
-fractional derivative and
- (ii)
For
, then
-fractional differentiable and
- (iii)
If
v and
are
-fractional differentiable, then
is a
-fractionald differentiable and
- (iv)
If
v is
-fractional differentiable, then
is
-fractional differentiable with:
- (v)
If
v and
are
-fractional differentiable, then
is
-fractional differentiable with:
valid at all points
for which
.
Lemma 1 (
Chain rule [
32])
. Suppose that is continuous and -fractional differentiable at , for and is continuously differentiable. Then is -fractional differentiable and Definition 2 (
Definition 26, [
31])
. For then the -fractional integral of , is defined as Theorem 2 (
Theorem 31, [
31])
. Suppose that . If , then- (vi)
- (vii)
- (viii)
- (ix)
- (x)
Lemma 2 (
Integration by parts formula [
31])
. Suppose that where . If are conformable -fractional differentiable and , then: Lemma 3 (
Hölder’s inequality [
32])
. Let where . If and , then
where
and
Through our paper, we will consider the integrals are given exist (are finite i.e., convergent).
3. Results
Here, we will exemplify our main results in this article by utilizing Hölder’s inequality, chain rule, and integration by parts for fractional on time scale.
Theorem 3. Suppose thatis a time scale with.
Define Proof. By utilizing the formula of integration by parts
on
with
and
, we have
where
Using
in
, we see that
By utilizing chain rule, we get:
Since
, we have
Next note
. By the chain rule, we have (note
)
This leads to
and then, we have
Substituting
into
yields:
Raises
to the factor
, we have:
By applying Hölder’s inequality
on the term
with indices
(note that
) and
we see that
This means that
by substitution
into
, we get
This means that
which the wanted inequality
□
Corollary 1. If we putin Theorem 6, then we get
where
which is
in the Introduction.
Remark 1. If we takein Theorem 6, then:
where
Remark 2. Clearly, forRemark 1 coincides with Remark 1 in [
25].
Remark 3. As a result, ifin (20),then:
where,
If
, then
becomes
where,
which is Remark 2 in [
25].
Theorem 4. Suppose thatbe a time scale with. Assume thatis defined as in Theorem 6 such that:
and define
. Then
Proof. Utilizing the formula of integration by parts
on
with
, we have
where
. This with
and implies that
But utilizing chain rule, we obtain:
Since
we find that
. By substituting
into
and using that
, we get
Next note
. By the chain rule, we have (note
)
By substituting (37) into (36) yields
Raising
to the factor
we get:
The rest of the proof is identical to the proof of Theorem and hence is deleted. □
Corollary 2. If we putin Theorem, then:
where
such that
which is
in the Introduction
Remark 4. If we takein Theorem, then
where
If
then (41) becomes:
which is Remark
in [
25].
Remark 5. As a special case ofwhenwe get:
where
which is Remark
in [
25], when
Theorem 5. Suppose thatis a time scale with. Assume that. Then Proof. Utilizing the formula of integration by parts (18) on
with
, we get
where
. This with
imply that
By utilizing chain rule, we get:
Since
. By substituting
into
and using that
, we have:
Next note
. By the chain rule, we have (note
)
By substituting
into
yields
Raises
to the factor
h, we get:
The rest of the proof is identical to the proof of Theorem 6 and hence is deleted. □
Corollary 3. If we putin Theorem, then:
where
which is
in the Introduction.
Remark 6. In Theorem 10, if we takethen:
where
If
and
, then
becomes
where
which is Remark 5 in [
25]
Remark 7. As a special case ofwhen, we get:
where
.
For
in
, then we get the inequality in Remark
in [
21].
Theorem 6. Suppose thatis a time scale withand. Assume thatsuch that and define Proof. Utilizing the formula of integration by parts
on
with
, we have
where
This with
imply that
By utilizing chain rule, we obtain:
Since
. By substituting
into
and using that
, we have:
Next note
. By the chain rule, we have (note
)
And
by substituting (60) into (59), we get
Raises
to the factor
, we get
The rest of the proof is identical to the proof Theorem 6 and hence is deleted. □
Corollary 4. If we putin Theorem, then:
where
which is
in the Introduction
Remark 8. If we takein Theorem, then:
where
If
then (63) becomes
where
which is Remark 7 in [
25]
Remark 9. As a special case of, whenwe get:
where,
which is Remark
in [
25], when
Applications
The applications of quantum calculus play an important role in mathematics and the field of natural sciences, such as physics and chemistry. It has many applications in orthogonal polynomials, number theory, quantum theory, etc. In this section, some example for Reverse Coposn’s Inequalities in fractional quantum calculus are selected to fulfil the applicability of the obtained results.
Now, we give an example using the time scale which is a time scale with interesting applications in quantum calculus.
Example 1. (Quantum calculus case 1.): Let.
Then for allwe have Now, with the help of Theorem
and the above identities in
we can deduce
where,
and
For an application of Theorem , we give the following example.
Example 2. (Quantum calculus case 2.): Letthen the relationis satisfy. Hence, we have: Now, with the help of Theorem
and the above identities in
we can deduce:
where,
is defined in the above example.
Note that. By using theorems 10 and 12, we can apply the technique used in the above examples to obtain different applications. In addition, the above result is important not only for arbitrary time scales, but also for quantum calculus.
4. Conclusions and Future Work
The new fractional calculus on timescales is presented with applications in new fractional inequalities on timescales like Hardy, Bennett, Copson, and Leindler types. Inequalities are considered in rather general forms and contain several special integral and discrete inequalities. The technique is based on the applications of well-known inequalities and new tools from fractional calculus. In future research, we will continue to generalize more dynamic inequalities by using Specht’s ratio, Kantorovich’s ratio, functional generalization, and n-tuple fractional diamond- α integral. It will be interesting to find the inequalities in α,β-symmetric quantum and stochastic calculus.