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QUITE THE QUESTION. “Several years ago I asked Scott Aaronson a question: Can it be proved that the complexity of a universal quantum circuit, such as those that have been conjectured to describe black holes, grows at the fastest possible rate—linearly with time—until it saturates at the maximum complexity (exponential in the number of qubits)?” https://lnkd.in/dByfCJV View in LinkedIn

QUANTUM AND BLACK HOLES. “It is not known what the limitations are on using quantum computation to speed up classical computation. An example would be the power to speed up PSPACE-complete computations. It is also not known what the limitations are on the duration of time over which classical general relativity can describe the interior geometry of black holes. What is known is that these two questions are closely connected: the longer GR can describe black holes, the more limited are quantum computers.” (GR = general relativity). https://lnkd.in/dByfCJV View in LinkedIn

ROLE IN EVOLUTION. “Recently through a series of observations it has been shown that supermassive black holes (SMBH) residing at the center of galaxies play a significant role in cosmic evolution of structure in the Universe.” https://lnkd.in/dq-SEai View in LinkedIn

Bougainvillea jumping genes causing electric strawberry on white background in the same plant. View in LinkedIn

“RINGWOODITE is the most common mineral phase in the lower transition zone of the Earth’s mantle, at depths of 525 to 660 km. This ringwoodite crystal contains about 1% water. If the whole ringwoodite of the mantle contains this amount of water, it is estimated that there is almost three times as much water in the mantle as in all the oceans combined.” https://lnkd.in/dNuAzU2 View in LinkedIn

NO HEN’S TOOTH. “Stellar-remnant black holes should be abundant in the local Universe.” https://lnkd.in/d8Jh7TB View in LinkedIn

PREVALENT BLACK HOLES. “Fig. 3 clearly shows that the overall black hole number density in the Universe is fairly high.” https://lnkd.in/d8Jh7TB View in LinkedIn

NUCLEOSYNTHESIS. “We see that for high metallicities (Z ≳ −1.5), a very large stellar progenitor (≳90M⊙) will be required to produce the massive black holes of the type that have been observed in mergers by LIGO. Lower metallicity populations require less extreme progenitors.” (LIGO = an observatory; M⊙ = unit of stellar mass in suns). https://lnkd.in/d8Jh7TB View in LinkedIn

ETERNAL FUTURE. “According to classical general relativity the volume of space behind the horizon of a black hole grows linearly (with time), into the eternal future.” (Time present and time past/Are both perhaps present in time future,/And time future contained in time past./If all time is eternally present/All time is unredeemable.” TSE Four Quartets). https://lnkd.in/dByfCJV View in LinkedIn

PUSHING THE ANALOGY. “Thus, θ(τ) < 0 for every τ may be proposed as the signal of jamming in this analogue gravity formulation of granular matter.” https://lnkd.in/dusKMKM View in LinkedIn