:: About Conference

Holography is indeed one of the main consequences of the string theory, which relates two different theories, for example, the quantum theory of gravity to the gauge field theory. The holographic principle has two sides, the first is quantum theories without gravity which are indeed experimentally relevant theories, and the second is classical theories of gravity, so applications in both (field theory and topology) are important. Applications of holography can relate to some physics branches like elementary particle physics, condensed matter physics, nuclear physics, astrophysics, and cosmology. The most famous application of holography well-known as AdS/CFT conjecture which suggests a relation between a conformal field theory (CFT) in d-dimensional space and a supergravity theory in (d+1)-dimensional anti-de Sitter (AdS) space. It is indeed usage of topology to study strongly coupled systems like quantum chromodynamics (QCD) at finite temperature or condensed matter theory (CMT). The former includes the study of the quark-gluon plasma (QGP) in four-dimensional space-time by using the string theory in five-dimensional AdS space-time. It is an elementary particle physics application (sometimes called the AdS/QCD correspondence), which is tested in modern particle accelerators. The latter includes a field theory description of a system with the chemical potential at a finite temperature which is the holographic dual of a charged black hole. It is a condensed matter application that includes holographic models of superconductor and superfluid (sometimes called the AdS/CMT correspondence), thermal behaviors of Fermi liquids, holographic model of Weyl semimetal states, or study of field theory hydrodynamics using a gravitational solution. This aspect of holography some time called gauge/gravity duality. As mentioned above, having temperature on the gauge field theory side is corresponding to have a black hole on the gravity side. Therefore, the study of black hole dynamics is important for holographic studies. Black holes also are important from another holographic point of view. The event horizon area of the black hole is as the holographic dual of the black hole entropy, and the black hole surface gravity is as the holographic dual of the black hole temperature. So, it helps us to study the black hole thermodynamics. It is indeed like a hologram where the maximum information of bulk is proportional to its area. At low (intermediate) temperatures physics where the theory is in confinement state, the only configuration is a connected eight-brane, there is a second-order phase transition at finite chemical potential (vacuum) to a nuclear matter phase. Moreover, chiral dynamics of hadrons, like baryons at low energy physics which are typical of strongly coupled QCD (bound state of 3 quarks via strong coupling) can be investigated using holography to calculate corresponding binding energy which also may test in experiments. Studying the nuclear force using string theory is one of the most important applications of holography. These are some applications of holography in nuclear physics which are another aspect of AdS/QCD. Application of the holographic principle to the dark energy problem in cosmology has been known as holographic dark energy. The study of se Sitter (dS) space-time and inflation is also important from dS/CFT as well as AdS/CFT correspondence point of view. Holographic description of inflationary universes can relate the cosmological observables, like the primordial power spectrum, to the correlation functions of a quantum field theory (QFT). Neutron stars are interesting systems for holographic application in astronomy and astrophysics. These systems include matter at low temperature while very high density (which yields to the existence of a deconfined quark phase), however, it is not so hot for application of perturbative QCD. Hence, AdS/CFT correspondence can help to study the neutron star equation of state. In that case, it has been suggested that degenerate composite operators of CFT are considered as holographic dual to degenerate stars in AdS space. The application of holography in laser and photonics is also broad interesting, such as the image reconstruction of objects, the generation of novel laser beams, and new designs in photonic micro- and nano-structures, etc. These are some examples of holographic applications in physics. The 1st International Conference of Holography and its Applications which hold virtually on 9-10 March 2022 deals with all applications of holography in all fields of science. All participants may send their paper for oral or poster presentation which will be reviewed by members of the scientific committee. The selected papers will be published as regular articles by JHAP .