Arab. J. Math.
https://doi.org/10.1007/s40065-022-00384-y Arabian Journal of Mathematics
Tarek Saanouni · Talal Alharbi
On the inter-critical inhomogeneous generalized Hartree
equation
Received: 3 November 2021 / Accepted: 5 May 2022
© The Author(s) 2022
Abstract It is the purpose of this work to study the Choquard equation
i ˙ u − (−)
s
u = ±|x |
γ
( I
α
∗|·|
γ
|u |
p
)|u |
p−2
u
in the space
˙
H
s
∩
˙
H
s
c
, where 0 < s
c
< s corresponds to the scale invariant homogeneous Sobolev norm.
Here, one considers to two separate cases. The first one is the classical case s = 1 and the second one is
the fractional regime 0 < s < 1 with radial data. One tries to develop a local theory using a new adapted
sharp Gagliardo–Nirenberg estimate. Moreover, one investigates the concentration of non-global solutions in
L
∞
T
∗
(
˙
H
s
c
). One needs to deal with the lack of a mass conservation, since the data are not supposed to be in L
2
.
This note gives a complementary to the previous works about the same problem in the energy space H
1
.
Mathematics Subject Classification 35Q55
1 Introduction
This paper is concerned with the Cauchy problem for a Choquard equation
i ˙ u + u = ǫ |x |
γ
( I
α
∗|·|
γ
|u |
p
)|u |
p−2
u ;
u
|t =0
= u
0
,
(1.1)
where u : R × R
N
→ C, for some integer N ≥ 1, ǫ =±1 refers to the attractive/repulsive regime. The above
problem is said inhomogeneous because of the singular quantity |·|
γ
, where γ< 0. The Riesz potential is
defined on R
N
by
I
α
:=
Ŵ(
N −α
2
)
Ŵ(
α
2
)π
N
2
2
α
|·|
N −α
, 0 <α< N .
T. Saanouni (B ) · T. Alharbi
Department of Mathematics, College of science and Arts in Uglat Asugour, Qassim university, Buraydah, Kingdom of Saudi
Arabia
E-mail: Tarek.saanouni@ipeiem.rnu.tn; t.saanouni@qu.edu.sa
T. Alharbi
Faculty of Science of Tunis, LR03ES04 Partial Differential Equations and Applications, University of Tunis El Manar,
2092 Tunis, Tunisia
E-mail: ta.alharbi@qu.edu.sa
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