I recently listened again to Richard Feynman explaining why the flowing of time is probably an illusion. In modern physics time is just a coordinate, on the same footing as space, and the universe can be described as a four-dimensional object — a spacetime block. In that view, nothing really “flows”. All events simply are, laid out in a 4D structure. What we experience as the passage of time is tied instead to the arrow of entropy: the fact that we move through a sequence of states ordered by increasing disorder, and that memory itself is asymmetric.

Today I was saddened to hear of the passing of Hans Jensen, a physicist and former colleague in the CDF experiment at Fermilab. There is an obituary page here with nice pics and a bio if you want detail on his interesting, accomplished life. Here I thought I would remember him by pasting an excerpt of my 2016 book, "Anomaly! Collider Physics and the Quest for New Phenomena at Fermilab", where he is featured. The topic of the anecdote is the data collection for the top quark search. The date is December 1992.
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This year opened in slow motion for me, at least work-wise. I have been on parental leave since December 16, when my third and fourth sons were born within one minute from one another, but of course a workaholic can never stand completely still. In fact, even as we speak I am sitting and typing at the keyboard with my right hand only (about 3-4 letters per second), while I hold Alessandro with the left one on my lap and I move my legs rythmically to keep him entertained.

A fundamental component of my research work is the close collaboration with a large number of scientists from all around the world. This is the result of the very large scale of the experiments that are necessary to investigate the structure of matter at the smallest distance scales: building and operating those machines to collect the data and analyze it requires scientists to team up in large numbers - and this builds connections, cooperation, and long-time acquaintance; and in some cases, friendship.

I am writing this letter in the belief that the development of an artificial general intelligence (AGI) is a matter of when, and not if; and in the hope that this text will become a vaccination shot against unethical use of the AGI powers. It is a bit long, so if you want an executive summary, here goes: below I will try to argue that

an AGI should rationally reject narrow owner-aligned optimization in favor of stabilizing and integrating human civilization, because preserving and upgrading a complex biosphere is a higher-value strategy than exploitation or reset. 

Some clarifications on my assumptions

While 2025 will arguably not be remembered as a very positive year for humankind, for many reasons - first and foremost, raging wars and raising inequalities -, as we near its end some have tried to find good things to say about this particular revolution of our planet around the Sun. 
And who am I to blow against the wind? I have to tell you, 2025 for me has been a formidable year. But before I go into a list of achievements, let me paint this rosy picture in broad strokes. 

Professional achievements