Collisions of rigidly rotating disks of dust in general relativity

Hennig, Joerg; Neugebauer, Gernot

doi:10.1103/physrevd.74.064025

Cited by 5 publications

(19 citation statements)

References 14 publications

(34 reference statements)

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“…The radius of the helix, which corresponds to the distribution of the center of mass of the residues, is fixed to R 0 = 2.8Å [2]. To model the vibron-phonon dynamics in a rather simple way, we follow the procedure introduced by Hennig [17] and treat the N residues as point-like entities which the equilibrium positions are located on sites distributed along the helix. Therefore, as shown in Fig.…”

Section: Helix Structure and Model Hamiltonianmentioning

confidence: 99%

“…However, it has been shown within the soliton approach, that when a vibron is excited on a single spine the 3D nature of the helix manifests itself by reducing the soliton velocity and by favoring the exchanges between spines [14,15,16]. Recently, a detailed analysis of both the soliton trapping and the soliton dynamics in a 3D α-helix has been done by Hennig [17]. It has been shown that the soliton envelop exhibits a monotonic decay but shows a multihump structure.…”

Section: Introductionmentioning

confidence: 99%

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Vibron-polaron in α-helices. I. Single-vibron states

Falvo

Pouthier

2005

The Journal of Chemical Physics

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The vibron dynamics associated to amide-I vibrations in a three-dimensional alpha-helix is described according to a generalized Davydov model. The helix is modeled by three spines of hydrogen-bonded peptide units linked via covalent bonds. To remove the intramolecular anharmonicity of each amide-I mode and to renormalize the vibron-phonon coupling, two unitary transformations have been applied to reach the dressed anharmonic vibron point of view. It is shown that the vibron dynamics results from the competition between interspine and intraspine vibron hops and that the two kinds of hopping processes do not experience the same dressing mechanism. Therefore, at low temperature (or weak vibron-phonon coupling), the polaron behaves as an undressed vibron delocalized over all the spines whereas at biological temperature (or strong vibron-phonon coupling), the dressing effect strongly reduces the vibrational exchanges between different spines. As a result the polaron propagates along a single spine as in the one-dimensional Davydov model. Although the helix supports both acoustical and optical phonons, this feature originates in the coupling between the vibron and the acoustical phonons only. Finally, the lattice distortion which accompanies the polaron has been determined and it is shown that residues located on the excited spine are subjected to a stronger deformation than the other residues.

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Section: Helix Structure and Model Hamiltonianmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Vibron-polaron in α-helices. I. Single-vibron states

Falvo

Pouthier

2005

The Journal of Chemical Physics

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“…The force constant K 2 is set to zero and we assume K |n| = 0 for n ≥ 4. The force constant of the hydrogen bonds is fixed to K 3 = 15 Nm −1 [11,16,19,20,23] whereas the force constant of the covalent bonds is equal to K 1 = 60 Nm −1 [23]. Finally, the mass M which enters the phonon dynamics has been fixed to 2.0 10 −25 kg.…”

Section: Numerical Resultsmentioning

confidence: 99%

“…(3) is given by the parameters χ |n−n ′ | [18] which accounts for the modulation of the nth amide-I frequency due to the external motion of the n ′ th residue. According to the 1D Davydov model, the parameter χ 3 ranges between 35 and 62 pN and we choose χ 2 = 0 whereas we treat χ 1 as a parameter smaller than χ 3 [23]. Note that χ n = 0 for n ≥ 4.…”

Section: Numerical Resultsmentioning

confidence: 99%

Vibron-polaron in α-helices. II. Two-vibron bound states

Falvo

Pouthier

2005

The Journal of Chemical Physics

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The two-vibron dynamics associated to amide-I vibrations in a three-dimensional (3D) alpha-helix is described according to a generalized Davydov model. The helix is modeled by three spines of hydrogen-bonded peptide units linked via covalent bonds. It is shown that the two-vibron energy spectrum supports both a two-vibron free states continuum and two kinds of bound states, called two-vibron bound states (TVBS)-I and TVBS-II, connected to the trapping of two vibrons onto the same amide-I mode and onto two nearest-neighbor amide-I modes belonging to the same spine, respectively. At low temperature, nonvanishing interspine hopping constants yield a three-dimensional nature of both TVBS-I and TVBS-II which the wave functions extend over the three spines of the helix. At biological temperature, the pairs are confined in a given spine and exhibit the same features as the bound states described within a one-dimensional model. The interplay between the temperature and the 3D nature of the helix is also responsible for the occurrence of a third bound state called TVBS-III which refers to the trapping of two vibrons onto two different spines. The experimental signature of the existence of bound states is discussed through the simulation of their infrared pump-probe spectroscopic response. Finally, the fundamental question of the breather-like behavior of two-vibron bound states is addressed.

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“…Therefore, is only an upper limit for the energy of the gravitational emission. We obtained a maximal value of RR max % 23:8% (Hennig & Neugebauer 2006).…”

Section: Formation Of Rigidly Rotating Disksmentioning

confidence: 99%

Thermodynamic Description of Inelastic Collisions in General Relativity

Neugebauer¹,

Hennig²

2008

The Eleventh Marcel Grossmann Meeting

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We discuss head-on collisions of neutron stars and disks of dust (''galaxies'') following the ideas of equilibrium thermodynamics, which compares equilibrium states and avoids the description of the dynamical transition processes between them. As an always present damping mechanism, gravitational emission results in final equilibrium states after the collision. In this paper we calculate selected final configurations from initial data of colliding stars and disks by making use of conservation laws and solving the Einstein equations. Comparing initial and final states, we can decide for which initial parameters two colliding neutron stars (nonrotating Fermi gas models) merge into a single neutron star and two rigidly rotating disks form again a final (differentially rotating) disk of dust. For the neutron star collision we find a maximal energy loss due to outgoing gravitational radiation of 2.3% of the initial mass, while the corresponding efficiency for colliding disks has the much larger limit of 23.8%.

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Collisions of rigidly rotating disks of dust in general relativity

Cited by 5 publications

References 14 publications

Vibron-polaron in α-helices. I. Single-vibron states

Vibron-polaron in α-helices. I. Single-vibron states

Vibron-polaron in α-helices. II. Two-vibron bound states

Thermodynamic Description of Inelastic Collisions in General Relativity

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