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If the interference between each pair of coarse-grained histories is zero...

If the interference between each pair of coarse grained histories is zero, either exactly or to an exceedingly good approximation, then all the coarse grained histories are said to decohere. The quantity $D$ of each coarse-grained history and itself is then a true probability, with the additive property. In practice, quantum mechanics is always applied to sets of decohering coarse-grained histories, and that is why it is able to predict probabilities. ($D$, by the way, is called the decoherence functional; the wod “functional” indicates that it depends on histories.)

The algorithmic information content of each alternative history of the universe...

The algorithmic information content of each alternative history of the universe evedently receives a tiny contribution from the simple fundamental laws, along with a gigantic contribution from all the quantum accidents that arise along the way. But it is not only the AIC of the universe that is dominated by those accidents. Although they are chance events, their effects contribute heavily to effective complexity as well.

Limerick on the speed of light

There was a young lady named Bright
Who could travel much faster than light.
She set out one day, in a relative way,
And returned home the previous night.

Extinction risk depends strongly on factors contributing to stochasticity

Extinction depends on four kinds of stochasticity. Models that do not incorporate all four kinds might greatly undererstimate extinction risks.

Using heterogeneity indices to adjust basal area – Leaf area index relationship in managed coniferous stands

Abstract (excerpt)

The structure of contemporary managed forests is complex and deviates from experimental forests which are usually even-aged monocultures and single-storied. To apply theoretical growth and yield functions on managed forests, adjustments are required, especially for leaf area index (LAI) which is a key biophysical variable in process-based growth models. To asses this, the performance of canopy LAI in modelling the basal area (BA, measured at breast height = 1.30m) of managed boreal forests dominated by Norway spruce (Picea abies (L). Karst) and Scots pine (Pinus sylvestris L.) was investigated by heterogeneity analysis. The study was based on the assumption that canopy LAI and BA are strongly related and are vital for estimating stand productivity and growth. Managed forests were represented by field data from the 2016 and 2017 Swedish National Forest Inventory (NFI) campaigns.

Moving beyond the incorrect but useful paradigm: reevaluating big-leaf and multilayer plant canopies to model biosphere-atmosphere fluxes – a review

Abstract

This article reviews the scientific debate of big-leaf vs multi-layer canopy modeling for land surface models. Comparisons with flux tower measurements show supremacy of good multi-layer models (5-10 layer suffice).

How to avoid having your manuscript rejected: Perspectives from the Editors-in-Chief of Soil Biology and Biogeochemistry

In this editorial piece the editors in chief of SBB explain to what authors should pay attention before submitting papers in general, and to SBB in particular.

Theory tends to emerge as a profession as a science matures...

Theory tends to emerge as a profession as a science matures and as the depth and power of theoretical methods increase. But the roles of theory and observation should be regarded as distinct whether or not there are separate classes of practitioners for the two activities.

Similarly, in the will of the Swedish dynamite magnate Alfred Nobel...

Similarly, in the will of the Swedish dynamite magnate Alfred Nobel, who established the Nobel prizes, the science prizes are listed with physics first, chemistry second, and physiology and medicine third. As a result, the physics prize is always awarded at the beginning of the ceremony in Stockholm. If there is just one physics prize winner and that winner is a married man, it is his wife who comes into dinner on the arm of the King of Sweden. (When my friend Abdus Salam, a citizen of Pakistan and a Muslim, received a share of the physics prize in 1979, he turned up in Sweden with his two wives, np doubt causing some problems of protocol to arise.) The winner or winners in chemistry rank second in protocol, and those in physiology and medicine third. Mathematics is omitted from Nobel’s will for reasons that are not really understood. There is a persistent rumor that Nobel was angy with a Swedish mathematician, Mittag-Leffler, for stealing the affections of a woman, but, as far as I know, it is only a rumor.

But is the information obrained from the outside world...

But is the information obtained from the outside world, for example from a parent who speaks the language in question, sufficient to construct such an internal grammar? That question has been answered in the negative by Noam Chomsky and his followers, who conlcude that the child must come already equipped at birth with a great deal of information applicable to the grammar of any natural human language. The only plausible source of such information is a biologically evolved innate proclivity to speak languages with certain grammatical features, shared by all natural human languages. The grammar of each individual languange also contains additional features, not biologically programmed. Many of those vary from language to language, although some are probably iniversal like the innate ones. The additional features are what the child has to learn.