Thursday, August 18, 2016

Science or speculation?

Merging of two black holes
In December 2013 several media made reference to an article published in the journal Physical Review Letters, in the field called quantum gravity, a set of mutually incompatible theories that in the last 30 years have scarcely formulated a single testable prediction, although they are usually presented as the latest in physics and give rise to news broadly popularized by the general media. This scientific news was presented by some media with this title: quantum entanglement causes the appearance of wormholes. Some of the reviews contained important mistakes. I’ll cite two:
1.      The group showed that, by creating two black holes intertwined, later separated, a wormhole appeared, a “shortcut”' through the universe, connecting the two distant black holes to one another.
Comment: the group did not show that. It just found some equations that suggest that this might happen (or not, because mathematics is not the same as physics). Moreover, these theoretical speculations are based on string theory, which is just one among several alternative proposals of quantum gravity existing today.
2.     To explore what emerges from two entangled quarks, Sonner first generated quarks using the Schwinger effect - a concept in quantum theory that enables the creation of particles out of nothing. More precisely, the effect, also called "pair creation," allows two particles to emerge from a vacuum. 
Julian Schwinger, Nobel Price 1965
Two comments.
First: Sonner did not generate anything, because the Schwinger effect has not yet been experimentally verified, even with electron-positron pairs, much less with quarks, so again we have the confusion of a mere theoretical study with something real. What Sonner really did was assume that the Schwinger effect is real, and that it can be used to generate quarks in a vacuum, in which case certain equations (which have not been proven) say that something could happen... As you see, this study is literally resting on the void.
Second: out of nothing one can create nothing. Nothing does not exist, as we know since the time of Parmenides. As usual, nothing is confused with the vacuum. A vacuum is not nothing, because it has several qualities (space, time, energy, existence) that nothing does not have.
Black hole at the center of a galaxy
Our current theories about quantum vacuum cannot be wholly correct, for they predict that the energy of the vacuum is infinite. Physicists solve this problem by a mathematical procedure called renormalization, a process that essentially involves dividing by infinity (which is forbidden by mathematics), equivalent to hiding the problem under the carpet.

One must be careful with scientific news appearing in the press. Some media are just looking for a headline impact. The accuracy of the scientific news, which perhaps ultimately may just be simple speculations, is usually less important.

Manuel Alfonseca

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