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Related papers: Large-Scale Magnetic Fields, Dark Energy and QCD

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The origin of the observed dark energy could be explained entirely within the standard model, with no new fields required. We show how the low-energy sector of the chiral QCD Lagrangian, once embedded in a non-trivial spacetime, gives rise…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Federico R. Urban , Ariel R. Zhitnitsky

The difference between vacuum energy of quantum fields in Minkowski space and in Friedmann-Robterson-Walker universe might be related to the observed dark energy. The vacuum energy of the Veneziano ghost field introduced to solve the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-26 Rong-Gen Cai , Zhong-Liang Tuo , Ya-Bo Wu , Yue-Yue Zhao

We suggest that the solution to the cosmological vacuum energy puzzle is linked to the infrared sector of the effective theory of gravity interacting with standard model fields, with QCD fields specifically. We work in the framework of low…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Federico R. Urban , Ariel R. Zhitnitsky

A so called "ghost dark energy" was recently proposed to explain the present acceleration of the universe expansion. The energy density of ghost dark energy, which originates from Veneziano ghost of QCD, is proportional to the Hubble…

General Physics · Physics 2011-11-04 Ahamd Sheykhi , Ali Bagheri

The Veneziano ghost field has been proposed as an alternative source of dark energy whose energy density is consistent with the cosmological observations. In this model, the energy density of QCD ghost field is expressed in terms of QCD…

High Energy Physics - Phenomenology · Physics 2016-05-18 K. Azizi , N. Katirci

We propose that cosmological magnetic fields generated in regions of finite spatial dimensions may manifest themselves in the global dynamics of the Universe as `dark energy'. We test our model in the context of spatially flat cosmological…

Astrophysics · Physics 2019-08-19 Ioannis Contopoulos , Spyros Basilakos

In this paper, we establish that the solution to the dark energy problem is connected to the cutoff Ultraviolet scale manifesting itself as linearly independent infrared sectors of the effective theory of gravity interacting with QCD…

High Energy Physics - Theory · Physics 2015-03-23 O. F. Akinto , Farida Tahir

It has been recently argued \cite{Barvinsky:2017lfl} that the de Sitter phase in cosmology might be naturally generated as a result of dynamics of the topologically nontrivial sectors in a strongly coupled QCD-like gauge theory in expanding…

High Energy Physics - Phenomenology · Physics 2019-05-22 Ariel R. Zhitnitsky

It has been suggested that the dark energy that explains the observed accelerating expansion of the universe may arise due to the contribution to the vacuum energy of the QCD ghost in a time-dependent background. The argument uses a…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Nobuyoshi Ohta

A ghost dark energy model has been recently put forward to explain the current accelerated expansion of the Universe. In this model, the energy density of ghost dark energy, which comes from the Veneziano ghost of QCD, is proportional to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Alberto Rozas-Fernandez

We study a phenomenological dark energy model which is rooted in the Veneziano ghost of QCD. In this dark energy model, the energy density of dark energy is proportional to Hubble parameter and the proportional coefficient is of the order…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Rong-Gen Cai , Qiping Su , Zhong-Liang Tuo , Hong-Bo Zhang

The accelerating expansion of the Universe points to a small positive vacuum energy density and negative vacuum pressure. A strong candidate is the cosmological constant in Einstein's equations of General Relativity. The vacuum dark energy…

High Energy Physics - Phenomenology · Physics 2012-10-12 Steven D. Bass

A new dark energy model called "ghost dark energy" was recently suggested to explain the observed accelerating expansion of the universe. This model originates from the Veneziano ghost of QCD. The dark energy density is proportional to…

High Energy Physics - Theory · Physics 2015-03-19 A. Sheykhi , M. Sadegh Movahed

In this work we consider quantum electromagnetic fields in an expanding universe. We start by reviewing the difficulties found when trying to impose the Lorenz condition in a time-dependent geometry. Motivated by this fact, we explore the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jose Beltran Jimenez , Antonio L. Maroto

Evidences indicate that the dark energy constitutes about two thirds of the critical density of the universe. If the dark energy is an evolving pseudo scalar field that couples to electromagnetism, a cosmic magnetic seed field can be…

Astrophysics · Physics 2015-06-24 Da-Shin Lee , Wolung Lee , Kin-Wang Ng

Recently, the vacuum energy of the QCD ghost in a time-dependent background is proposed as a kind of dark energy candidate to explain the acceleration of the universe. In this model, the energy density of the dark energy is proportional to…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-22 Chao-Jun Feng , Xin-Zhou Li , Xian-Yong Shen

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…

Astrophysics · Physics 2007-05-23 Kari Enqvist

The origin of the substantial magnetic fields that are found in galaxies and on even larger scales, such as in clusters of galaxies, is yet unclear. If the second-order couplings between photons and electrons are considered, then…

We study physics concerning the cosmological constant problem in the framework of effective field theory and suggest that a dominant part of dark energy can originate from gravitational corrections of vacuum energy, under the assumption…

High Energy Physics - Theory · Physics 2017-02-24 Yugo Abe , Masaatsu Horikoshi , Yoshiharu Kawamura

In this paper, we propose a mechanism to generate large-scale magnetic fields with correlations lengths of 100 kpc. Domain walls with QCD scale internal structure form and coalesce obtaining Hubble size correlations and align nucleon spins.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael McNeil Forbes , Ariel R. Zhitnitsky
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