• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    BOUNDEDNESS OF VARIATION OPERATORS ASSOCIATED WITH THE HEAT SEMIGROUP GENERATED BY HIGH ORDER SCHRDINGER TYPE OPERATORS?

    2020-11-14 09:40:34SuyingLIU劉素英
    關(guān)鍵詞:張超

    Suying LIU (劉素英)

    Department of Applied Mathematics, Northwest Polytechnical University, Xi’an 710072, China

    E-mail : suyingliu@nwpu.edu.cn

    Chao ZHANG (張超)?

    School of Statistics and Mathematics, Zhejiang Gongshang University, Hangzhou 310018, China

    E-mail : zaoyangzhangchao@163.com

    “square function” of the typewhere ti0, or more generally the variation operator Vρ(Tt), where ρ >2, is given by

    where the supremum is taken over all the positive decreasing sequences{tj}j∈Nwhich converge to 0. We denote with Eρthe space including all the functions w :(0,∞)→ R such that

    wEρis a seminorm on Eρ; it can be written as

    In this article, we mainly focus on the variation operators associated with the high order Schrdinger type operators L=(??)2+V2in Rnwith n ≥ 5,where the nonnegative potential V belongs to the reverse Hlder class RHqfor some q > n/2; that is, there exists C > 0 such that

    for every ball B in Rn. Some results related to(??)2+V2were first considered by Zhong in[29].In [25], Sugano proved the estimation of the fundamental solution and the Lp-boundedness of some operators related to this operator. For more results related to this operator,see[7,17,18].

    The heat semigroup e?tLgenerated by the operator L can be written as

    The kernel of the heat semigroup e?tLsatisfies the estimate

    for more details see [1].

    We recall the definition of the function γ(x), which plays an important role in the theory of operators associated with L:

    This was introduced by Shen [21].

    Theorem 1.1Assume that V ∈ RHq0(Rn), where q0∈ (n/2,∞) and n ≥ 5. For ρ > 2,there exists a constant C >0 such that

    We should note that our results are not contained in the article of Bui [4], because the estimates of the heat kernel are not the same.

    On the other hand, Zhang and Wu [28]studied the boundedness of variation operators associated with the heat semigroup {e?tL}t>0on Morrey spaces related to the non-negative potential V. Tang and Dong [26]introduced Morrey spaces related to non-negative potential V for extending the boundedness of Schrdinger type operators in Lebesgue spaces.

    Definition 1.2Let 1 ≤ p < ∞,α ∈ R, and 0 ≤ λ < n. Forand V ∈RHq(q >1), we say that

    where B(x0,x) denotes a ball centered at x0and with radius r and γ(x0) is defined as in (1.2).

    For more information about the Morrey spaces associated with differential operators, see[10, 23, 27].

    We can now also obtain the boundedness of the variation operators associated to the heat semigroup {e?tL}t>0on Morrey spaces.

    Theorem 1.3Let V ∈ RHq0(Rn) for q0∈ (n/2,∞), n ≥ 5, and ρ > 2. Assume that α ∈ R and λ ∈ (0,n). There exists a constant C >0 such that

    The organization of the article is as follows: Section 2 is devoted to giving the proof of Theorem 1.1. In order to prove this theorem, we should study the strong Lp-boundedness of the variation operators associated with {e?t?2}t>0first. We will give the proof of Theorem 1.3 in Section 3. We also obtain the strong Lp(Rn) estimates (p > 1) of the generalized Poisson operatorson Lpspaces as well as Morrey spaces related to the non-negative potential V,in Sections 2 and 3, respectively.

    Throughout this article, the symbol C in an inequality always denotes a constant which may depend on some indices, but never on the functions f under consideration.

    2 Variation Inequalities Related to {e?tL}t>0 on Lp Spaces

    In this section, we first recall some properties of the biharmonic heat kernel. With these kernel estimates,we will give the proof of Lp-boundedness properties of the variation operators related to {e?t?2}t>0, which is crucial in the proof of Theorem 1.1.

    2.1 Biharmonic heat kernel

    Consider the following Cauchy problem for the biharmonic heat equation:

    Its solution is given by

    where Jvdenotes the v-th Bessel function and αn>0 is a normalization constant such that

    and g(η) satisfies the following estimates

    see [14]. Then, by classical analysis, we have the following results (for details, see [24]):

    (a) If f ∈ Lp(Rn), 1 ≤ p ≤ ∞, then

    (b) If 1 ≤ p< ∞, then

    We should note that the heat semigroup e?t?2does not have the positive preserving property; that is,when f ≥ 0, e?t?2f ≥ 0 may not to be established. Thus,the boundedness of the variation operators associated with {e?t?2}t>0cannot be deduced by the results in [11].

    For the heat kernel b(x,t) of the semigroup e?t?2, we have the following estimates:

    Lemma 2.1For every t>0 and Rn, we have

    ProofFor (2.3) and (2.4), see Lemma 2.4 in [14]. From (2.1), (2.2), and some simple calculations, we can derive (2.5) and (2.6).

    2.2 Variation inequalities related to {e?t?2}t>0

    By Lemma 2.1 in Section 2.1, we know that the operator e?t?2is a contraction on L1(Rn)and L∞(Rn). Thus, e?t?2is contractively regular. Then, by [15, Corollary 3.4], we have the following theorem (for more details, see [15]):

    Theorem 2.2For ρ>2, there exists a constant C >0 such that

    2.3 Variation inequalities related to {e?tL}t>0

    First, we recall some properties of the auxiliary function γ(x), which will be used later.

    Lemma 2.3([21]) Let VThen there exist C and k0> 1 such that for all x,y ∈Rn,

    In particular, γ(x)~ γ(y) if |x ? y|

    Lemma 2.4(Lemma 2.7 in[7]) Let V ∈ RHq0(Rn)and δ =2?n/q0,where q0∈ (n/2,∞)and n ≥ 5. Then there exists a positive constant C such that for all x,y ∈ Rnand t ∈ (0,γ4(x)],

    where A4=min{A,A1} and A,A1are constants as in (1.1) and (2.3), respectively.

    Now we can prove the following kernel estimates of e?tL:

    Lemma 2.5For every N ∈N, there exist positive constants C, A2, and A3such that for all x,y ∈ Rnand 0

    ProofFor (i), see Theorem 2.5 of [7].

    Now we give the proof of (ii). As L = (??)2+V2is a nonnegative self-adjoint operator,we can extend the semigroup {e?tL} to a holomorphic semigroup {Tξ}ξ∈?π/4uniquely. By a similar argument as to that in [8, Corollary 6.4], the kernel Bξ(x,y) of Tξsatisfies

    The Cauchy integral formula combined with (2.7) gives

    Thus, we complete the proof.

    With the estimates above, we can give the proof of Theorem 1.1.

    Proof of Theorem 1.1For f ∈ Lp(Rn),1 ≤ p< ∞, we consider the local operators

    Then, we have

    Let us analyze term J2first:

    Now, we consider the operator defined by

    which is bounded from L2(Rn) intoaccording to Theorem 2.2. Moreover, T is a Caldern-Zygmund operator with the Eρ-valued kernel b(x?y,t). In fact, the kernel b(x?y,t)has the following two properties:

    (A) By (2.5), we have

    (B) Proceeding a similar way, together with (2.4), we have

    Thus, by proceeding as in the proof of [22, Proposition 2 in p.34 and Corollary 2 in p.36],we can prove that the maximal operator T?defined by

    is bounded on Lp(Rn) for every 1 < p < ∞. Combining this with Theorem 2.2, we conclude thatis bounded from Lp(Rn) into itself for every 1

    Next, we consider term J3:

    To estimate J31, by Lemma 2.5 with N =n+2 and changing variables, we have

    where M(f) is the Hardy-Littlewood maximal function of f. For J32, by Lemma 2.5, we have

    Thus,from the estimates J31and J32,we have J3≤CM(f)(x),which implies that the operatoris bounded from Lp(Rn) into itself for every 1

    Finally, we consider the term J1:

    Applying Lemma 2.1 and Lemma 2.5, we have

    The formula (2.7) in [7]implies that

    Then we have

    We rewrite J12as

    Using (2.3), and Lemmas 2.5 and 2.4, we obtain

    As a consequence,

    Next, we note that when 0

    Hence,

    As in the previous proof, proceeding with a similar computation, we can also obtain

    Owing to the above estimates, we know that J12≤ CM(f)(x). Consequently, we have J1≤CM(f)(x). As M(f) is bounded from Lp(Rn) into itself for every 1 < p < ∞, the proof of Theorem 1.1 is complete.

    2.4 The generalized Poisson operators

    For 0< σ <1, the generalized Poisson operatorassociated with L is defined as

    For the variation operator associated with the generalized Poisson operatorswe have the following theorem:

    Theorem 2.6Assume that V ∈ RHq0(Rn), where q0∈ (n/2,∞) and n ≥ 5. For ρ > 2,there exists a constant C >0 such that1

    ProofWe note that

    Then, for 1

    3 Variation Inequalities on Morrey Spaces

    In this section, we will give the proof of Theorem 1.3. For convenience, we first recall the the definition of classical Morrey spaces Lp,λ(Rn), which were introduced by Morrey [20]in 1938.

    Definition 3.1Let 1 ≤ p< ∞, 0 ≤ λ < n. Forwe say that f ∈ Lp,λ(Rn)provided that

    where B(x0,r) denotes a ball centered at x0and with radius r.

    In fact, when α = 0 or V = 0 and 0< λ < n, the spaceswhich were defined in Definition 1.2, are the classical Morrey spaces Lp,λ(Rn).

    We establish the Lp,λ(Rn)-boundedness of the variation operators related to{e?t?2}t>0as follows:

    Theorem 3.2Let ρ>2 and 0<λ

    ProofFor any fixed x0∈Rnand r > 0, we write f(x) =where f0 =fχB(x0,2r), fi =fχB(x0,2i+1r)B(x0,2ir) for i ≥ 1. Then

    For I, by Theorem 2.2, we have

    For II, we first analyze Vρ(e?t?2)(fi)(x). For every i ≥ 1,

    Note that for x ∈ B(x0,r) and y ∈ RnB(x0,2r), we know thatBy using(2.5), we have

    The proof of this theorem is complete.

    The following is devoted to the proof of Theorem 1.3.

    Proof of Theorem 1.3Without loss of generality, we may assume that α<0. Fixing any x0∈Rnand r >0, we write

    where f0=fχB(x0,2r), fi=fχB(x0,2i+1r)B(x0,2ir)for i ≥ 1. Then

    From (i) of Theorem 1.1, we have

    For II, we first analyze Vρ(e?tL)(fi)(x). For every i ≥ 1,

    Note that for x ∈ B(x0,r) and y ∈ RnB(x0,2r), we have |x ? y| >We discussin two cases. For the one case, |x0?y|≤ γ(x0), by(ii) of Lemma 2.5 we have

    For the other case, |x0? y| ≥ γ(x0), applying (ii) of Lemma 2.5 together with Lemma 2.3 we have

    Combining (3.1), (3.2) and (3.3), we have

    Thus, taking N =[?α]+1, we obtain

    The proof of the theorem is completed.

    Finally, we can give the boundedness of the variation operators related to generalized Poisson operatorsin the Morrey spaces as follows:

    Theorem 3.3Let V ∈ RHq0(Rn) for q0∈ (n/2,∞), n ≥ 5, and ρ > 2. Assume that α ∈ R and λ ∈ (0,n). There exists a constant C >0 such that

    ProofWe can prove this theorem by the same procedure used in the proof of Theorem 2.6.

    猜你喜歡
    張超
    張超,《平安夜》,不銹鋼,高310cm,2023
    張超個人簡介
    散文百家(2021年11期)2021-11-12 03:06:38
    My New Invention
    How to Protect Us from Infectious Diseases
    張超個人簡介
    散文百家(2021年4期)2021-04-30 03:15:20
    張超個人簡介
    散文百家(2021年2期)2021-04-03 14:08:22
    張超攝影展
    攝影與攝像(2020年7期)2020-09-10 07:22:44
    張超作品
    創(chuàng)意立體燈籠賀卡
    英國人的度假歷史
    天门市| 淮阳县| 多伦县| 宕昌县| 九龙城区| 长白| 日照市| 天台县| 民权县| 云霄县| 萨迦县| 临洮县| 辰溪县| 平乡县| 连州市| 和静县| 鄢陵县| 无棣县| 报价| 南投县| 乐山市| 庆阳市| 西乌珠穆沁旗| 山丹县| 延川县| 台东市| 尼勒克县| 图木舒克市| 周至县| 交口县| 扶风县| 永吉县| 桦南县| 扶余县| 定边县| 湾仔区| 淄博市| 合阳县| 营山县| 南宫市| 齐河县|