We know we don't know

A few days ago on Nature Astronomy it was published a paper by a team of italian researchers with an unequivocal title: Planck evidence for closed Universe and a possible crisis for cosmology⁽⁶⁾. We can consider it as one of the first scientific articles that seriously takes into consideration a situation that it is becoming increasingly pressing: a crisis in cosmology.
The standard cosmological model, based on cosmic inflation⁽²⁾ and on empirical constants that evaluate unknown physical quantities as dark matter and dark energy, although very well verified, has not yet passed the last step: the detection of gravitational waves in cosmic microwave background (CMB). One of the fundamental points of this model, but also of many of the surviving competing models, is the accelerated expansion of spacetime at speed greater than that of light which explains the flatness of the early universe.
This flatness emerges in particular when studying the cosmic microwave background, the residual energy of the initial expansion of spacetime. This radiation has come down to us from the point where it was produced, a little less than 14 billion years ago, crossing the whole universe. This means that in the signal detected there must also be gravitational lens effects⁽¹⁾ due to the amount of matter, usual and dark, present in the universe. These effects have long been known and calculated⁽⁴⁾ and can already be seen in the image produced by Planck⁽⁵⁾.

Planck results, ATLAS and the dark matter

http://t.co/jJxD8rhCr6 by @ulaulaman about #Planck, #ATLAS, #DarkMatter at #LHC

The last issue of Astronomy & Astrophysics (that it's free) is devoted to the Planck 2013 results:

This collection of 31 articles presents the initial scientific results extracted from this first Planck dataset, which measures the cosmic microwave background (CMB) with the highest accuracy to date. It provides major new advances in different domains of cosmology and astrophysics.

In the first paper there is an overview of 2013 science results, and we can read:

The Universe observed by Planck is well-fit by a six parameter, vacuum-dominated, cold dark matter (ACDM) model, and we provide strong constraints on deviations from this model.

But, in the meanwhile, ATLAS published a preprint about the quest of the dark matter in LHC:

The data are found to be consistent with the Standard Model expectations and limits are set on the mass scale of effective field theories that describe scalar and tensor interactions between dark matter and Standard Model particles. Limits on the dark-matter--nucleon cross-section for spin-independent and spin-dependent interactions are also provided. These limits are particularly strong for low-mass dark matter. Using a simplified model, constraints are set on the mass of dark matter and of a coloured mediator suitable to explain a possible signal of annihilating dark matter.

Tommaso Dorigo, examining ATLAS' results, concludes:

the ATLAS search increases significantly the sensitivity with respect to past searches, but no signal is found. As attractive as DM existence is as an economical explanation of a wealth of cosmological observations, the nature of dark matter continues to remain unknown.

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via phys.org