Change in the Universe’s Gravity May Have Helped Kill Off the Dinosaurs

There is little doubt that a huge asteroid hit Earth 66 million years ago near Mexico’s Yucatan Peninsula and the impact and its resulting destruction exterminated the dinosaurs and most of the rest of life on the planet. That has always seemed to be a random act of really bad luck (for the dinosaurs at least) but a new study proposes that it may not have been an accident – it could be that a flux in the gravity of the universe pulled the rock out of its orbital belt and drew it to Earth. Is it true? Could it happen again?

“This increase is consistent with observational evidence from the terrestrial and lunar cratering rates indicating that the impact flux of kilometer sized objects increased by at least a factor of 2 over that last 100 Myrs compared to the long term average. This increase may also be connected with the Chicxulub impactor event that produced the Cretaceous-Tertiary (K-T) extinction of 75% of life on Earth (including dinosaurs) about 66 Myrs ago.”

In his paper, “Is the Hubble crisis connected with the extinction of dinosaurs?”, Leandros Perivolaropoulos, a physicist at the University of Ioannina in Greece, connects the Chicxulub crater and the Cretaceous–Paleogene extinction event to a theoretical change in gravity beginning 150 million years ago which affected the entire universe. The weak link in this connection which doubting scientists point to is Newton’s constant (6.674 30 x 10^-11 m³ kg^-1 s^-2) – the empirical physical constant in Sir Isaac Newton's law of universal gravitation and in Albert Einstein's general theory of relativity … a constant so famous it can go by just one letter – G. In a simple Wikipedia explanation of G:

“In Newton's law, it is the proportionality constant connecting the gravitational force between two bodies with the product of their masses and the inverse square of their distance. In the Einstein field equations, it quantifies the relation between the geometry of spacetime and the energy–momentum tensor (also referred to as the stress–energy tensor).”

Gee. What does G have to do with the Chicxulub comet? Perivolaropoulos proposes that the constant was NOT constant – he thinks it increased by 10% starting 150 million years ago and ending 50 million years ago. During those 100 million years of flux, the baseline of gravity's force across the universe went up, pulling space objects together with a greater force. In our solar system, that force could have messed with the Oort Cloud of comets and asteroids – pulling them out of their orbits and towards bigger space rocks … like planets.

“The impact flux of kilometer-sized objects increased by at least a factor of two over that last 100 million years compared to the long-term average.”

For evidence to support his theory, The Daily Beast explains that Perivolaropoulos points to the geological record of Earth and the moon which shows an increase in craters caused by massive comets and asteroids during this alleged universe-wide disturbance in G. That is also the hole in the theory, according to Ben Montet, an astronomer at the University of New South Wales in Australia. If Earth pulled a killer comet to itself, so should have the rest of the planets in the inner solar system. And?

“There is no geological evidence to believe this is the case.”

However … The Daily Beast reveals that a number of astrophysicists think our ever-expanding universe is not growing smoothly (that's the Hubble constant which Perivolaropoulos refers to in the title of his paper) but in fits and starts (the Hubble crisis), and there is evidence that a period of rapid slow-down occurred … wait for it … between 150 million and 50 million years ago! Perivolaropoulos knows his theory is controversial – his paper has not yet been peer-reviews – and he wants to expand it beyond our solar system and the Milky Way to other galaxies and search for similar gravitational fluxes during the same time period as the Chicxulub event.

Is Newton's constant a non-constant constant? That would REALLY change everything.