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Related papers: The Triple-Alpha Process and the Anthropically All…

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In theories in which different regions of the universe can have different values of the the physical parameters, we would naturally find ourselves in a region which has parameters favorable for life. We explore the range of anthropically…

High Energy Physics - Phenomenology · Physics 2011-05-12 V. Agrawal , S. M. Barr , J. F. Donoghue , D. Seckel

In nucleosynthesis three possible paths are known to bridge the mass gaps at A=5 and A=8. The primary path producing the bulk of the carbon in our Universe proceeds via the triple-alpha process He4(2alpha,gamma)C12. This process takes place…

Nuclear Theory · Physics 2007-05-23 Heinz Oberhummer , Attila Csoto , Helmut Schlattl

The bulk of the carbon in our universe is produced in the triple-alpha process in helium-burning red giant stars. We calculated the change of the triple-alpha reaction rate in a microscopic 12-nucleon model of the C-12 nucleus and looked…

Astrophysics · Physics 2009-10-31 Heinz Oberhummer , Attila Csoto , Helmut Schlattl

Through the triple-alpha process occurring in red giant stars the bulk of the carbon existing in our universe is produced. We calculated the change of the triple-alpha reaction rate for slight variations of the nucleon-nucleon force using a…

Astrophysics · Physics 2016-11-03 Heinz Oberhummer , Attila Csoto , Helmut Schlattl

The properties of the Higgs potential are determined by three parameters: the mass parameter, the quartic self-coupling, and a constant term. Remarkably, all three of these parameters seem subject to a significant amount of fine-tuning. All…

High Energy Physics - Phenomenology · Physics 2024-05-07 Thomas Steingasser

The Hoyle state plays a crucial role in the helium burning of stars that have reached the red giant stage. The close proximity of this state to the triple-alpha threshold is needed for the production of carbon, oxygen, and other elements…

Nuclear Theory · Physics 2015-06-12 Evgeny Epelbaum , Hermann Krebs , Timo A. Lähde , Dean Lee , Ulf-G. Meißner

The extension of the standard model to SU(3)_L x SU(3)_R x SU(3)_C is considered. Spontaneous symmetry breaking requires two Higgs field multiplets with a strong hierarchical structure of vacuum expectation values. These vacuum expectation…

High Energy Physics - Phenomenology · Physics 2013-05-30 Berthold Stech

We present an ab initio calculation of the quark mass dependence of the ground state energies of ^4He, ^8Be and ^{12}C, and of the energy of the Hoyle state in ^{12}C. These investigations are performed within the framework of lattice…

Nuclear Theory · Physics 2013-09-03 Evgeny Epelbaum , Hermann Krebs , Timo A. Lähde , Dean Lee , Ulf-G. Meißner

The triviality of the scalar sector of the standard one-doublet Higgs model implies that this model is only an effective low-energy theory valid below some cut-off scale Lambda. For a heavy higgs this scale must be relatively low (10 TeV or…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Sekhar Chivukula , Nick Evans

We make an estimate of the likelihood function for the Higgs vacuum expectation value by imposing anthropic constraints on the existence of atoms while allowing the other parameters of the Standard Model to also be variable. We argue that…

High Energy Physics - Phenomenology · Physics 2010-04-22 John F. Donoghue , Koushik Dutta , Andreas Ross , Max Tegmark

We show that the synthesis of carbon and oxygen through the triple-alpha process in red giant stars is extremely sensitive to the fine details of the nucleon-nucleon (N-N) interaction. A +/-0.5% change in the strength of the N-N force would…

Nuclear Theory · Physics 2009-11-06 Attila Csoto , Heinz Oberhummer , Helmut Schlattl

One of the puzzles of the Standard Model is why the mass parameter which determines the scale of the Weak interactions is closer to the scale of QCD than to the Grand Unification or Planck scales. We discuss a novel approach to this problem…

High Energy Physics - Phenomenology · Physics 2011-05-12 V. Agrawal , S. M. Barr , John F. Donoghue , D. Seckel

Motivated by the possible existence of other universes, this paper considers the evolution of massive stars with different values for the fundamental constants. We focus on variations in the triple alpha resonance energy and study its…

Solar and Stellar Astrophysics · Physics 2018-10-24 Lillian Huang , Fred C. Adams , Evan Grohs

Both parameters in the Higgs field's potential, its mass and quartic coupling, appear fine-tuned to near-critical values, which gives rise to the hierarchy problem and the metastability of the electroweak vacuum. Whereas such behavior…

High Energy Physics - Phenomenology · Physics 2024-10-16 Thomas Steingasser , David I. Kaiser

We have studied imposing the condition that the Standard Model effective Higgs potential should have two approximately degenerate vacua, such that the vacuum we live in is just barely metastable: the one in which we live has a vacuum…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. D. Froggatt , H. B. Nielsen , Y. Takanishi

A brief review of the role of the Higgs mechanism and the ensuing Higgs particle in the Minimal Standard Model is given. Then the property of triviality of the scalar sector in the Minimal Standard Model and the upper bound on the Higgs…

High Energy Physics - Phenomenology · Physics 2009-09-25 Urs M. Heller

Theory with $SU(2)\times U(1)$ gauge invariant electroweak Lagrangian describing standard interaction of massless quark doublet without elementary scalar Higgs sector is considered. We show in the main order of $1/N_c$ expansion, that there…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. A. Arbuzov

The small and negative value of the Standard Model Higgs quartic coupling at high scales can be understood in terms of anthropic selection on a landscape where large and negative values are favored: most universes have a very short-lived…

High Energy Physics - Phenomenology · Physics 2015-06-26 Francesco D'Eramo , Lawrence J. Hall , Duccio Pappadopulo

A new $U(1)$ dark gauge group coupled to the Standard Model (SM) via the kinetic mixing portal provides a natural dark matter candidate in the form of the Higgs field, $h_d$, responsible for generating the mass of the dark photon,…

High Energy Physics - Phenomenology · Physics 2021-03-03 Cristina Mondino , Maxim Pospelov , Joshua T. Ruderman , Oren Slone

The vacuum expectation value $v_s$ of a Higgs triplet field $\Delta$ carrying two units of lepton number $L$ induces neutrino masses $\propto v_s$. The neutral component of $\Delta$ gives rise to two Higgs particles, a pseudoscalar $A$ and…

High Energy Physics - Phenomenology · Physics 2021-07-21 Gabriela Barenboim , Ulrich Nierste
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