Sunday - Thoughts on Quantum Loop Gravity and commuting into Grand Central Terminal

I tried to step away from the esoteric parts of quantum physics but found myself taking a short course on Quantum Loop Gravity from the World Science University. It was interesting, I learned some things and came away not convinced that QLG is the solution to the problem of quantum gravity. The professor, Dr. Carlo Rovelli is simultaneously convincing and unconvincing. He makes a strong case for the need for a theory of quantum gravity and for the quantum nature of spacetime at the smallest scale - Planck sized, but he does not convince me that QLG is the answer. 

He discusses how quantum gravity is needed to understand the structure of a black hole and that which is called a singularity since General Relativity breaks down in trying to explain it, and his description of how something that, for an external observer takes 10 billion years to happen, the creation of a white hole, is almost instantaneous inside the black hole, where gravity approaches infinity and time slows, relative to the outside viewer, almost to zero. He describes the white hole as a time reversed black hole. And he even posits an astronomical phenomena as possible evidence for the actual existence of white holes, Fast radio bursts, whose sources are still not understood.

Ok, I admit it, I was fascinated and momentarily even seduced by the ideas. And then I got down to selecting some photos.

These were taken on two days about 5 weeks apart. Both times I detrained at about the same time, same track, and descended into the E. 47th St. Cross Passage of Grand Central Terminal North.

I will let you guess which were from mid-April and which from late May this year. I think the difference in the number of people is a big clue.

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