Related papers: Color-Kinematics Duality for QCD Amplitudes
Continuing our previous study \cite{Du:2011se} of permutation sum of color ordered tree amplitudes of gluons, in this note, we prove the large-$z$ behavior of their cyclic sum and the combination of cyclic and permutation sums under BCFW…
Using variational methods, we numerically investigate the matrix model for the two-color QCD coupled to a single quark (matrix-QCD$_{2,1}$) in the limit of ultra-strong Yang-Mills coupling ($g =\infty$). The spectrum of the model has…
Tree-level amplitudes in N=4 SYM can be decomposed into partial or color-ordered amplitudes. Identities relating various partial amplitudes have been known since the 80's. They are Kleiss-Kuijf (KK) identities. In 2008, Bern, Carrasco and…
The phase diagram of two color QCD under influence of baryon density ($\mu_B$), isospin ($\mu_I$), chiral ($\mu_5$ and $\nu_5$) imbalances is investigated within the framework NJL model approach. This letter establishes the existence of…
We propose new formulae for the two-loop n-point D-dimensional integrands of scattering amplitudes in Yang-Mills theory and gravity. The loop integrands are written as a double-forward limit of tree-level trivalent diagrams, and are…
We give a unified description of tree-level multigluon amplitudes in the high-energy limit. We represent the Parke-Taylor amplitudes and the Fadin-Kuraev-Lipatov amplitudes in terms of color configurations that are ordered in rapidity on a…
We present the two-loop helicity amplitudes for the scattering of massless quarks in QCD. We use projector techniques to compute the coefficients of the general four-quark amplitude at up to two-loops in conventional dimensional…
Mesons constructed from the quark propagators without the lowest-lying eigenmodes of the Dirac operator reveal not only restored SU(2)_L * SU(2)_R chiral and U(1)_A symmetries, but actually a higher symmetry. All possible chiral and U(1)_A…
It is commonly believed that ${\pi}^0 \to 2 \gamma$ decay shows that there are three colours in Quantum Chromodynamics (QCD). It is shown here that this is not correct. When correct colour dependent charges of the quarks are considered then…
2-color QCD at finite temperature T and chemical potential \mu is revisited in the strong coupling limit on the lattice. The phase structure in the space of T, \mu and the quark mass m is elucidated with the use of the mean field…
Quantum chromodynamics predicts that the interaction between its fundamental constituents, quarks and gluons, can lead to different states of strongly interacting matter, dependent on its temperature and baryon density. We first survey the…
The quark exchange model is a simple realization of an adiabatic approximation to the strong-coupling limit of Quantum Chromodynamics (QCD): the quarks always coalesce into the lowest energy set of flux tubes. Nuclear matter is thus modeled…
The success of QCD factorization(QCDF) in predicting branching ratios for charmless $B$ decays to light pseudoscalar and vector mesons and the small CP asymmetries measured at $BABAR$, Belle and LHCb show that the phase in these decays, as…
The BCJ duality between color and kinematics brings two advantages to calculating multi-loop scattering amplitudes. First the number of ordered cuts that need to be performed to fix the integrand to a gauge theory is minimal -- reducing the…
A disorder parameter detecting dual superconductivty of the vacuum is used as a probe to characterize the confining properties of the phase diagram of two color QCD at finite temperature and density. We obtain evidence for the disappearing…
We study two-color QCD with two flavors of Wilson fermion as a function of quark chemical potential mu and temperature T, for two different lattice spacings and two different quark masses. We find that the quarkyonic region, where the…
We take a major step towards computing $D$-dimensional one-loop amplitudes in general gauge theories, compatible with the principles of unitarity and the color-kinematics duality. For $n$-point amplitudes with either supersymmetry…
A supersymmetric composite model of color superconductivity is proposed. Quarks and diquarks are dynamically generated as composite fields by a newly introduced strong gauge dynamics. It is shown that the condensation of the scalar…
The mass difference of $c$ and $u$ quarks is similar to the energy needed to excite gluonic degrees of freedom in strong QCD. This underpins the degeneracy of $D$ and a recently observed candidate hybrid excitation of the $\pi$ at$\sim…
The efficient computation of color-summed QCD amplitudes at high parton multiplicities remains a central challenge for precision collider predictions. Existing approaches using trace, color-flow, or adjoint bases suffer from…