We point out that if a certain variant of Quirks, particles that carry ordinary color and some other color exist, then we can have a completely novel and efficient mode of long distance communications and of acceleration to very high energies. For ve
ry low scale $Lambda$ the scale of the new gauge group in the theory, and associated string tension of the new color the Quirks can be captured in ordinary materials. Having then the Quirk Q and anti-Quirk $bar{Q}$ in two separate piezoelectric crystals at arbitrarily far out points A and B allows Alice and Bob at these locations to communicate by generating transverse waves along the connecting color string. Also releasing the Quirks allows them to collide at extremely high energies.
We address the impossibility of achieving exact time reversal in a system with many degrees of freedom. This is a particular example of the difficult task of aiming an initial classical state so as to become a specific final state. We also comment on
the classical-to-quantum transition in any non-separable closed system of $n geq 2$ degrees of freedom. Even if the system is initially in a well defined WKB, semi-classical state, quantum evolution and, in particular, multiple reflections at classical turning points make it completely quantum mechanical with each particle smeared almost uniformly over all the configuration space. The argument, which is presented in the context of $n$ hard discs, is quite general. Finally, we briefly address more complex quantum systems with many degrees of freedom and ask when can they provide an appropriate environment to the above simpler systems so that quantum spreading is avoided by continuously leaving imprints in the environment. We also discuss the possible connections with the pointer systems that are needed in the quantum-to-classical collapse transitions.
In this paper, we discuss limits on various astro-particle scenarios if the scale textit{and} the reheat temperature of the last relevant inflation were very high. While the observed B like pattern of polarizations of the CMB suggest a very high ($ge
10^{16} GeV$) scale of a primordial (which motivated this work initially) and may reflect effects of dust, we believe that addressing these issues is nonetheless very useful. We recall the potential difficulties with various topological defects - monopoles, strings and domain walls generated at the SSB (spontaneous symmetry breaking) of various gauge symmetries. The main part of the paper is devoted to discussing difficulties with long-lived heavy particles, which could be dark matter but cannot efficiently annihilate to the required residual density because of basic S-Matrix unitarity/analyticity limits. We indicate in simple terms yet in some detail how the WIMP miracle occurs at $M(X)sim{TeV}$ and how the axiomatic upper bound presently updated to $M(X) le{110 TeV}$ was originally derived by Greist and Kamionokowski. We also argue that generically we expect the stronger $M(X)le{20 GeV}$ bound to hold. We then elaborate on the pure particle physics approaches aiming to enhance the annihilation and evade the bounds. We find that the only and in fact very satisfactory way of doing this requires endowing the particles with gauge interactions with a confinement scale lower than $M(X)$. We also comment on models with light $O(KeV)$ dark matter, which was supposed to be frozen in via out-of equilibrium processes so as to have the right relic densities pointing out that in many such cases textit{very} low reheat temperatures are indeed required and speculate on the large desert scenario of particle physics. Most of what we discuss is not new but was not presented in a coherent fashion.
We calculate the Doppler broadening of the $W^-$ resonance produced in $bar{ u}_e e^-$ collisions of cosmic anti-neutrinos with $E_{ u}approx 6.3 PeV$ with electrons in atoms up to Iron. Revisiting this issue is prompted by recent observations of Pe
V neutrinos by Ice-Cube. Despite its poor energy resolution, the $20%$ Doppler broadening of the resonance due to electronic motions can produce observable effects via non-linear neutrino absorption near the resonance. The attendant suppression of the peak cross section allows $bar{ u}_e$ to travel correspondingly longer distances. While this effect is unlikely to be directly detected in the near future, it may facilitate terrestrial tomography at depths of $sim 10 km$, complementing deeper explorations using the more frequent nuclear interactions at lower energies.
We argue that the $125 GeV$ Higgs particle is unlikely to arise as a fermion- antifermion composite if the underlying dynamics is a vectorial gauge theory. The reason is that the lightest scalar in such theories is heavier than the lightest pseudo-sc
alar with the mass difference being fixed by the scale of the theory. LHC searches suggest that the scale of any new physics, including that of a putative new theory dynamically generating the 125 GeV Higgs particle, is relatively high $sim{(1/2TeV-1TeV)}$. Also the LHC analysis suggests that it is {it scalar} namely $J^P = 0^+$ rather than pseudo-scalar. Thus it is unlikely that the Higgs could arise as a composite in such theories- though it will arise in special cases when the underlying binding gauge group is real as a fermion-fermion bound state. The direct considerations of the various two point functions in the large $N_c$ limit presented below- suggest that massless pseudo-scalars, but not any other anomalously light meson, arise as composites of massless fermions say the massless u and $bar{d}$ quarks in QCD. These massless pions manifest the spontaneous breaking of the global axial symmetry in QCD with the pions being (pseudo) Nambu Goldstone Bosons. This offers a different insight into SXSB in QCD and most other confining non-abelian gauge vectorial gauge theory. Specifically we consider the euclidean two point functions $F_I|x-y|$ for asymptotic $|x-y|$ expressed as a sum over fermionic paths. We conjecture that for the pseudo-scalar two point function - and for that case only- self retracing paths and closely related paths make in this limit a positive, coherent and dominant contribution, a contribution which evades the generic asymptotic exponential fall-off and allows the lightest pseudoscalars to be massless. The same arguments imply that the scalars are very massive.
