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Classical roots of the Unruh and Hawking effects  [PDF]
Massimo Pauri,Michele Vallisneri
Physics , 1999,
Abstract: Although the Unruh and Hawking phenomena are commonly linked to field quantization in "accelerated" coordinates or in curved spacetimes, we argue that they are deeply rooted at the classical level. We maintain in particular that these effects should be best understood by considering how the special-relativistic notion of "particle" gets blurred when employed in theories including accelerated observers or in general-relativistic theories, and that this blurring is an instantiation of a more general behavior arising when the principle of equivalence is used to generalize classical or quantum special-relativistic theories to curved spacetimes or accelerated observers. A classical analogue of the Unruh effect, stemming from the non-invariance of the notion of "electromagnetic radiation" as seen by inertial and accelerated observers, is illustrated by means of four gedanken-experimente. The issue of energy balance in the various cases is also briefly discussed.
Some Heuristic Semiclassical Derivations of the Planck Length, the Hawking Effect and the Unruh Effect  [PDF]
Fabio Scardigli
Physics , 2002, DOI: 10.1007/BF02726152
Abstract: The formulae for Planck length, Hawking temperature and Unruh-Davies temperature are derived by using only laws of classical physics together with the Heisenberg principle. Besides, it is shown how the Hawking relation can be deduced from the Unruh relation by means of the principle of equivalence; the deep link between Hawking effect and Unruh effect is in this way clarified.
Equivalence between a Gravity Field and an Unruh Acceleration Temperature Field as a Possible Clue to “Dark Matter”  [PDF]
Eugene Terry Tatum, U. V. S. Seshavatharam
Journal of Modern Physics (JMP) , 2018, DOI: 10.4236/jmp.2018.98098
Abstract: Einstein’s equivalence principle allows one to compare the magnitudes of a gravitational acceleration field with the magnitudes of a field of Unruh acceleration temperatures. The validity of such a comparison is demonstrated by using it to derive the effective Hawking black body radiation at a Schwarzschild black hole horizon. One can then extend the black hole thought experiment to a Hawking-Unruh temperature equation expressed in terms of the Schwarzschild radius. This follows an inverse radius law rather than an inverse radius-squared law. Following a brief discussion of current theoretical failures to explain galactic rotation curves, the Unruh acceleration temperature equations are brought together to show how a rotating supermassive black hole galactic system should follow an inverse radius rule of centripetal gravitational force and centripetal acceleration. This result appears to indicate that galactic observations currently attributed to dark matter may in part be attributed to classical Newtonian dynamics superimposed on a relativistic rotating system powered by a supermassive black hole.
Hawking radiation, chirality, and the principle of effective theory of gravity  [PDF]
Adamantia Zampeli,Douglas Singleton,Elias C. Vagenas
Physics , 2012, DOI: 10.1007/JHEP06(2012)097
Abstract: In this paper we combine the chirality of field theories in near horizon regions with the principle of effective theory of gravity to define a new energy-momentum tensor for the theory. This new energy-momentum tensor has the correct radiation flux to account for Hawking radiation for space-times with horizons. This method is connected to the chiral anomaly cancellation method, but it works for space-times for which the chiral anomaly cancellation method fails. In particular the method presented here works for the non-asymptotically flat de Sitter space-time and its associated Hawking-Gibbons radiation, as well as Rindler space-time and its associated Unruh radiation. This indicates that it is the chiral nature of the field theory in the near horizon regions which is of primary importance rather than the chiral anomaly.
On Hawking/Unruh Process: Where does the Radiation Come from?  [PDF]
Tadas K. Nakamura
Physics , 2008,
Abstract: The energy source of the radiation in Unruh/Hawking process is investigated with emphasis on the particle number definition based on conservation laws. It has been shown that the particle radiation is not the result of pair creation by the gravitational force, but the result of difference in the conservation laws to define the particle number. The origin of the radiated energy in the distant future corresponds to the zero point oscillations with infinitely large wave numbers. This result implies the need of reconsideration on the scenario of black hole evaporation.
Hawking-Unruh radiation as irreversible consequence of radiative action in dynamics  [PDF]
D. Das
Physics , 2009,
Abstract: Radiation force in Abraham-Lorentz-Dirac equation is analyzed for possible signature of irreversible action over and above the well known reaction from Larmor radiation. The analysis shows that in the presence of jerk, the classical electron dissipates a certain fraction of field-particle interaction energy. Radiative dissipation occurs only when jerk has orthogonal component to acceleration to impart gyration action. The radiative temperature is generally estimated and is shown to corroborate to Hawking-Unruh temperature for electrodynamics at the event horizon of a gravitating body.
Thermal Hadronization and Hawking-Unruh Radiation in QCD
Castorina, P.;Kharzeev, D.;Satz, H.
High Energy Physics - Phenomenology , 2007, DOI: 10.1140/epjc/s10052-007-0368-6
Abstract: We conjecture that because of color confinement, the physical vacuum forms an event horizon for quarks and gluons which can be crossed only by quantum tunneling, i.e., through the QCD counterpart of Hawking radiation by black holes. Since such radiation cannot transmit information to the outside, it must be thermal, of a temperature determined by the chromodynamic force at the confinement surface, and it must maintain color neutrality. We explore the possibility that the resulting process provides a common mechanism for thermal hadron production in high energy interactions, from $e^+e^-$ annihilation to heavy ion collisions.
Hawking radiation via Anomaly and Tunneling method from Unruh's and Canonical acoustic black hole  [PDF]
Ramon Becar,Pablo Gonzalez,Gustavo Pulgar,Joel Saavedra
Physics , 2008,
Abstract: Hawking radiation from Unruh's and Canonical acoustic black hole is considered from viewpoint of anomaly cancellation method developed by Robinson and Wilczek. Thus, the physics near the horizon can be described using an infinite collection of massless two-dimensional scalar fields in the background of a dilaton and the gravitational anomaly is canceled by the flux of a 1 + 1 dimensional blackbody at the Hawking temperature of the space-time. Consequently, by this method, we can get the Hawking's temperature for Canonical and Unruh's acoustic black hole.
A simplified quantum theoretical derivation of the Unruh and Hawking temperature  [PDF]
Vladan Pankovic,Darko Kapor
Physics , 2010,
Abstract: In this work we suggest a sufficiently simple for understanding "without knowing the details of the quantum gravity" and quite correct deduction of the Unruh temperature (but not whole Unruh radiation process!). Firstly, we shall directly apply usual consequences of the Unruh radiation and temperature at surface gravity of a large spherical physical system and we shall show that corresponding thermal energy can be formally quite correctly presented as the potential energy absolute value of the classical gravitational interaction between this large and a small quantum system with well defined characteristics. Secondly, we shall inversely "postulate" small quantum system with necessary well defined characteristics and then, after "supposition" on the equivalence between potential energy absolute value of its gravitational interaction with large system with thermal energy, we shall obtain exact value of the Unruh temperature. Moreover, by very simple and correct application of suggested formalism (with small quantum system) at thermodynamic laws, we shall successfully study other thermodynamic characteristics, especially entropy, characteristic for Unruh and Hawking radiation
Why does the Unruh effect rely on Lorentz invariance, while Hawking radiation does not ?  [PDF]
David Campo,Nathaniel Obadia
Physics , 2010,
Abstract: We show that without Lorentz invariance, the Unruh effect does not exist. We use modified dispersion relations and describe in turn: the non-thermal nature of the vacuum (defined in the preferred frame) restricted to the Rindler wedge, the loss of the KMS property of the Wigthman function, the transition amplitudes and transition rates of a uniformaly accelerated detector. This situation seems to contrast with the Hawking radiation of acoustic black holes, which under certain assumptions has been shown to be robust to a breaking of Lorentz symmetry. We explain this discrepancy.
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