Reply to: “Comment on: ‘Exposed-key weakness of αη’ [Phys. Lett. A 370 (2007) 131]” [Phys. Lett. A 372 (2008) 7091]

We present simulations countering the claims in [R. Nair, H.P. Yuen, Phys. Lett. A 372 (2008) 7091] that the approximation given in [C. Ahn, K. Birnbaum, Phys. Lett. A 370 (2007) 131, quant-ph/0612058] for the eavesdropper's entropy on the encrypted key cannot be valid, and additionally discuss ways in which our views on security requirements differ from those given in [R. Nair, H.P. Yuen, Phys. Lett. A 372 (2008) 7091].     

Comment on “Convergence of macrostates under reproducible processes” [Phys. Lett. A 374 (2010) 3715]

In this Letter, two counterexamples show that the superadditivity inequality of relative entropy is not true even for the full-ranked quantum states. Thus, an inequality of quantum channels and complementary channels is not also true. Finally, a conjecture of weak superadditivity inequality is presented.     

Comment on: “Entanglement in three coupled oscillators” [Phys. Lett. A 384 (2020) 126134]

In this comment we analyze a method for the solution of the eigenvalue equation for three coupled harmonic oscillators proposed recently. We argue that the authors did not obtain the frequencies and coordinates of the normal modes that make the Hamiltonian operator diagonal but merely six transcendental equations for the relevant parameters that they did not attempt to solve. We derive the conditions for the existence of bound states that the authors did not appear to be able to obtain probably because of the complexity exhibited by those equations.     

Reply to: “Comment on: ‘Spherical Kadomtsev–Petviashvili equation and nebulons for dust ion-acoustic waves with symbolic computation’ ” [Phys. Lett. A 361 (2007) 520]

Dusty plasmas exist almost everywhere in the Universe and relevant nonlinear studies are encouragingly going to non-planar geometry. On our recent construction of a spherical Kadomtsev–Petviashvili model for the dust-ion-acoustic waves in a cosmic dusty plasma [B. Tian, Y.-T. Gao, Phys. Lett. A 340 (2005) 243], Hong [W.P. Hong, Phys. Lett. A (2006), doi:10.1016/j.physleta.2006.11.021, in press] comments that certain interesting coordinate transformations exist, with presentation of a transformed equation (TE) and nebulon solutions. In this Reply, we point out that the TE is valuable to the studies on both cosmic plasmas and applied mathematics. We obtain an auto-Bäcklund transformation on the TE and more general nebulons. With series of pictures, we discuss nebulon structures out of the TE, and address that there are cosmic plasma systems for which the TE is valid. We remove a constraint set in that Comment so that the TE can be useful for the Saturn-F-ring-typed dusty plasmas as well.     

Comment on: “Two elementary proofs of the Wigner theorem on symmetry in quantum mechanics” [Phys. Lett. A 372 (2008) 6847]

The second of the two proofs of the Wigner theorem on symmetry in quantum mechanics given in Simon et al. (2008) [1] is reexamined and refined to remove a possible gap in the argument presented there.     

Erratum to: “Quantum dissipative dynamics using the Doebner–Goldin equation” [Phys. Lett. A 376 (2012) 3033]

A few misprints appearing in the Letter [Phys. Lett. A 376 (2012) 3033] are corrected.     

Comment on “Stabilization of trapless Bose-Einstein condensates without any management” [Phys. Lett. A 383 (17) (2019) 2033-2038]

A recent paper by T. Ramakrishnan and S. Subramaniyan shows that there is an enhancement of the stability of the trapless BECs due to the inclusion of the higher-order interaction along with the two-and three-body interactions. We point out and correct the erroneous results calculated by the authors concerning the effective potential of the trapless BECs. In addition we have shown that the incorrect expression used by authors leads to notable discrepancies between such results and exact ones. Moreover, our numerical results coincide with our theoretical predictions.     

Addendum to: “Geometrical and topological aspects of electrostatics on Riemannian manifolds” [J. Geom. Phys. 57 (8) (2007) 1679–1696]

In this note we discuss and solve several open problems posed in our recent paper “Geometrical and topological aspects of electrostatics on Riemannian manifolds”, also published in this journal. Some minor mistakes therein are corrected as well.     

Reply to the Comment by F. Kožíšek et al. on “Evidence for the existence of stable-water-clusters at room temperature and normal pressure” [Phys. Lett. A 373 (2009) 3872]

After discussing various points raised in a recent comment by F. Ko?íšek et al., who claim that our Letter “Evidence for the existence of stable-water-clusters at room temperature and normal pressure” (Phys. Lett. A 373 (2009) 3872) is unclear and the evidence is scant, we conclude that their arguments are wrong.     

Comment on “Spherical particle Brownian motion in viscous medium as non-Markovian random process” [Phys. Lett. A 375 (2011) 4113]

In this comment, we show that the results presented in Letter “Spherical particle Brownian motion in viscous medium as non-Markovian random process” are not new, the old results from the literature are not correctly recalculated, and the used method of integral transforms is not applicable for consideration of the Brownian motion with memory.     

Addendum to: “Ricci-flat holonomy: A classification” [J. Geom. Phys. 57 (6) 1457–1475]: The case of spin(10)

This note fills a hole in the author’s previous paper “Ricci-flat holonomy: A classification”, by dealing with irreducible holonomy algebras that are subalgebras or real forms of C⊕spin(10,C)$\mathbb{C}\oplus \mathfrak{s}\mathfrak{p}\mathfrak{i}\mathfrak{n}(10,\mathbb{C})$. These all turn out to be of Ricci type.     

Comment on “Convergence towards asymptotic state in 1-D mappings: A scaling investigation” [Phys. Lett. A 379 (18–19) (2015) 1246–1250]

Nonequilibrium phase transitions are characterized by the so-called critical exponents, each of which is related to a different observable. Systems that share the same set of values for these exponents also share the same universality class. Thus, it is important that the exponents are named and treated in a standardized framework. In this comment, we reinterpret the exponents obtained by Teixeira et al. [1] for the logistic and cubic maps in order to correctly state the universality class of their bifurcations, since these maps may describe the mean-field solution of stochastic spreading processes.     

Comment on “Quantum telegraph: is it possible?” by B.B. Kadomtsev (Phys. Lett. A 210 (1996) 371)

The possibility of a quantum telegraph using the so-called Sokolov effect is reexamined under the fundamental principle of quantum mechanics. The conclusion is negative.     

Corrigendum to “Constraints on operator ordering from third quantization” [Ann. Phys. 365 (2016) 54–65]

In our previous paper (Ohkuwa et al., 2016) corrigendum was found in Eqs. (3.4) and (3.6). However, conclusions of our previous paper are not changed.     

Corrigendum to “Constraints on operator ordering from third quantization” [Ann. Phys. 365 (2016) 54–65]

In our previous paper Ohkuwa et al. (2016) corrigendum was found in Eqs. (3.4) and (3.6). However, conclusions of our previous paper are not changed.