Physical consequences of P$\neq$NP. (arXiv:1010.0128v2 [quant-ph] UPDATED): “

Computational complexity theory is applied to simulations of adiabatic

quantum computation, providing predictions about the existence of quantum phase

transitions in certain disordered systems. Moreover, bounds on their

entanglement entropy at criticality are given. Concretely, physical

consequences are drawn from the assumption that the complexity classes P and NP

differ.

Quantum ChromoDynamics. (arXiv:1010.2330v1 [hep-ph]): “

These lectures on QCD stress the theoretical elements that underlie a wide

range of phenomenological studies, particularly gauge invariance,

renormalization, factorization and infrared safety. The three parts cover the

basics of QCD, QCD at tree level, and higher order corrections.

Statistical properties of entropy production derived from fluctuation theorems. (arXiv:1010.2319v1 [cond-mat.stat-mech]): “

Several implications of well-known fluctuation theorems, on the statistical

properties of the entropy production, are studied using various approaches. We

begin by deriving a tight lower bound on the variance of the entropy production

for a given mean of this random variable. It is shown that the Evans-Searles

fluctuation theorem alone imposes a significant lower bound on the variance

only when the mean entropy production is very small. It is then nonetheless

demonstrated that upon incorporating additional information concerning the

entropy production, this lower bound can be significantly improved, so as to

capture extensivity properties. Another important aspect of the fluctuation

properties of the entropy production is the relationship between the mean and

the variance, on the one hand, and the probability of the event where the

entropy production is negative, on the other hand. Accordingly, we derive upper

and lower bounds on this probability in terms of the mean and the variance.

These bounds are tighter than previous bounds that can be found in the

literature. Moreover, they are tight in the sense that there exist probability

distributions, satisfying the Evans-Searles fluctuation theorem, that achieve

them with equality. Finally, we present a general method for generating a wide

class of inequalities that must be satisfied by the entropy production. We use

this method to derive several new inequalities which go beyond the standard

derivation of the second law.

Techniques for n-Particle Irreducible Effective Theories. (arXiv:1010.2978v1 [hep-ph]): “

In this paper we show that the skeleton diagrams in the m-Loop nPI effective

action correspond to an infinite resummation of perturbative diagrams which is

void of double counting at the m-Loop level. We also show that the variational

equations of motion produced by the n-Loop nPI effective theory are equivalent

to the Schwinger-Dyson equations, up to the order at which they are consistent

with the underlying symmetries of the original theory. We use a diagrammatic

technique to obtain the 5-Loop 5PI effective action for a scalar theory with

cubic and quartic interactions, and verify that the result satisfies these two

statements.

An overview of the theories of the glass transition. (arXiv:1010.2938v1 [cond-mat.stat-mech]): “

The topic of the glass transition gives rise to a a wide diversity of views.

It is, accordingly, characterized by a lack of agreement on which would be the

most profitable theoretical perspective. In this chapter, I provide some

elements that can help sorting out the many theoretical approaches,

understanding their foundations, as well as discussing their validity and

mutual compatibility. Along the way, I describe the progress made in the last

twenty years, including new insights concerning the spatial heterogeneity of

the dynamics and the characteristic length scales associated with the glass

transition. An emphasis is put on those theories that associate glass formation

with growing collective behavior and emerging universality.

Particle cosmology. (arXiv:1010.2642v1 [hep-ph]): “

In these lectures the present status of the so-called standard cosmological

model, based on the hot Big Bang theory and the inflationary paradigm is

reviewed. Special emphasis is given to the origin of the cosmological

perturbations we see today under the form of the cosmic microwave background

anisotropies and the large scale structure and to the dark matter and dark

energy puzzles.

High-energy astroparticle physics. (arXiv:1010.2647v1 [hep-ph]): “

In these three lectures I discuss the present status of high-energy

astroparticle physics including Ultra-High-Energy Cosmic Rays (UHECR),

high-energy gamma rays, and neutrinos. The first lecture is devoted to

ultra-high-energy cosmic rays. After a brief introduction to UHECR I discuss

the acceleration of charged particles to highest energies in the astrophysical

objects, their propagation in the intergalactic space, recent observational

results by the Auger and HiRes experiments, anisotropies of UHECR arrival

directions, and secondary gamma rays produced by UHECR. In the second lecture I

review recent results on TeV gamma rays. After a short introduction to

detection techniques, I discuss recent exciting results of the H.E.S.S., MAGIC,

and Milagro experiments on the point-like and diffuse sources of TeV gamma

rays. A special section is devoted to the detection of extragalactic magnetic

fields with TeV gamma-ray measurements. Finally, in the third lecture I discuss

Ultra-High-Energy (UHE) neutrinos. I review three different UHE neutrino

detection techniques and show the present status of searches for diffuse

neutrino flux and point sources of neutrinos.

Fundamental physics in observational cosmology. (arXiv:1009.4327v1 [astro-ph.CO]): “

I discuss, through a few examples, how observational cosmology can provide

insights on hypothetical fundamental physics phenomena or mechanisms, such as

Grand Unified Theory, Superstring alternatives to the inflation paradigm, and

inflation itself.

Identifying the Inflaton. (arXiv:1009.3741v1 [astro-ph.CO]): “

We explore the ability of experimental physics to uncover the underlying

structure of the gravitational Lagrangian responsible for inflation. It is a

common expectation that improved measurements of the primordial perturbations

will result in a better understanding of the nature of the inflaton field. We

investigate to what extent this expectation is justifiable within the context

of a general inflationary Lagrangian. Our conclusion is that observables beyond

the adiabatic and tensor two-point functions on CMB scales are needed; in

particular, isocurvature modes or a combination of local non-Gaussiantities and

a precision measurement of the tensor spectral index will enable the most

successful reconstructions. We show that amongst these observables, the most

powerful probe of the inflationary Lagrangian is a precision measurement of the

tensor spectral index, as might be possible with a direct detection of

primordial gravitational waves.

The World as Evolving Information. (arXiv:0704.0304v3 [cs.IT] CROSS LISTED): “

This paper discusses the benefits of describing the world as information,

especially in the study of the evolution of life and cognition. Traditional

studies encounter problems because it is difficult to describe life and

cognition in terms of matter and energy, since their laws are valid only at the

physical scale. However, if matter and energy, as well as life and cognition,

are described in terms of information, evolution can be described consistently

as information becoming more complex.

The paper presents eight tentative laws of information, valid at multiple

scales, which are generalizations of Darwinian, cybernetic, thermodynamic,

psychological, philosophical, and complexity principles. These are further used

to discuss the notions of life, cognition and their evolution.

That’s all folks!

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