The paper by T. Senthil, Ashvin Vishwanath, Leon Balents, Subir Sachdev, and Matthew P. A. Fisher explores the concept of "deconfined" quantum critical points in two-dimensional antiferromagnets. Traditional theories of critical phenomena, such as the Ginzburg-Landau-Wilson (GLW) paradigm, often rely on the existence of an order parameter to describe phase transitions. However, the authors argue that in certain quantum systems, the critical behavior is not well described by such a parameter. In their study, the authors focus on quantum phase transitions between different broken symmetry phases, such as the Néel state and valence bond solid (VBS) state in antiferromagnets. They show that the critical theory at these transitions involves a new emergent gauge field and "deconfined" degrees of freedom associated with fractionalization of the order parameters. This means that the critical theory is not simply described by the order parameter fields of the bulk phases but by new degrees of freedom specific to the critical point. The authors provide a detailed theoretical framework for this new paradigm, using the example of a two-dimensional quantum magnet with spin-$S = 1/2$ moments. They demonstrate that the critical theory at the transition between the Néel and VBS phases involves an emergent U(1) gauge field and spinon fields, which are confined in the VBS phase but emerge as natural degrees of freedom at the critical point. This deconfinement is characterized by the conservation of a global topological charge, the skyrmion number, which is absent in the microscopic Hamiltonian. The paper also discusses the implications of this new paradigm for the physical properties near the quantum critical point, such as the anomalous dimension of the Néel order and the behavior of vortices in the XY ordered phase. The authors suggest that this deconfined quantum criticality may provide a key to understanding experimental puzzles in correlated electron systems, including high-$T_c$ superconductors and heavy fermion materials.The paper by T. Senthil, Ashvin Vishwanath, Leon Balents, Subir Sachdev, and Matthew P. A. Fisher explores the concept of "deconfined" quantum critical points in two-dimensional antiferromagnets. Traditional theories of critical phenomena, such as the Ginzburg-Landau-Wilson (GLW) paradigm, often rely on the existence of an order parameter to describe phase transitions. However, the authors argue that in certain quantum systems, the critical behavior is not well described by such a parameter. In their study, the authors focus on quantum phase transitions between different broken symmetry phases, such as the Néel state and valence bond solid (VBS) state in antiferromagnets. They show that the critical theory at these transitions involves a new emergent gauge field and "deconfined" degrees of freedom associated with fractionalization of the order parameters. This means that the critical theory is not simply described by the order parameter fields of the bulk phases but by new degrees of freedom specific to the critical point. The authors provide a detailed theoretical framework for this new paradigm, using the example of a two-dimensional quantum magnet with spin-$S = 1/2$ moments. They demonstrate that the critical theory at the transition between the Néel and VBS phases involves an emergent U(1) gauge field and spinon fields, which are confined in the VBS phase but emerge as natural degrees of freedom at the critical point. This deconfinement is characterized by the conservation of a global topological charge, the skyrmion number, which is absent in the microscopic Hamiltonian. The paper also discusses the implications of this new paradigm for the physical properties near the quantum critical point, such as the anomalous dimension of the Néel order and the behavior of vortices in the XY ordered phase. The authors suggest that this deconfined quantum criticality may provide a key to understanding experimental puzzles in correlated electron systems, including high-$T_c$ superconductors and heavy fermion materials.