Book Report – Dark Matter, Dark Energy
Begin: 2/2/2024
Finish: 3/22/2024
Title: Dark Matter, Dark Energy
Author: Professor Sean Carroll
California Institute of Technology
Why I choose to read this book:
To learn more of the unknown inn the world. Dark Matter and Dark Energy is current been probed by CERN to investigate the makeup of atoms using the linear accelerator. Knowledge of science pique my interest.
What I learned from this book:
Cosmologist were able to discover a complete inventory of the universe: 5% ordinary matter (atoms, stars, galaxies), 25% Dark Matter ( New matter that has not been detected on earth) and 70% Dark Energy. The dark energy is something new and completely unexpected; a kind of energy density that seemingly exists even in completely empty space. Dark Matter and Dark energy hold the key to the ultimate fate of the universe.
Our universe is big; it consists of billions of stars, scattered nearly uniform throughout space and it is getting bigger. Galaxies are moving apart from each other as the space between them expands. The entire picture is accurately described by General Relativity, by Einstein’s Theory of Spacetime and gravity. Gravity is used to probe ingredients that compose the universe. Even if we don’t se something, it will still have a gravitational field. The logic is: the motion of galaxies imply the need for more matters than we see; we call this extra stuff Dark Matter. Dark Matter could be ordinary matter that isn’t emitting or absorbing light, but that possibility can be ruled out. There are no particles in the Standard Model that could describe the Dark Matter, it must be something new and undiscovered. From the Cosmic Microwave Background, relic radiation from when the universe first became transparent, the tiny fluctuation in the temperature of this radiation are tied to the composition of the universe and provide additional evidence that Dark Matter is something new.
Even newer is Dark Energy – something that isn’t made of particles and is smoothly distributed through space and slowly evolving through time. The Dark Energy has dramatic effect on the universe; its affects the overall curvature of space and causes the expansion rate of the universe to accelerate. These effects have been observed, leaving little doubt that Dark Energy exists. But What is it?
Few candidates for Dark Energy but none make sense. the idea of vacuum energy , it is quite natural, but its magnitude is not; if vacuum energy exists at all, it should be much greater than what we observe. Alternatively, cosmologists have theorized hat Dark Energy arises from some new dynamical field called Quintessence. This possibility has the attractive feature of being experimentally testable; if Dark Energy is varying with time, future experiment can reveal it.
Despite supporting evidence, there is a more dramatic possibility that Dark Matter and Dark Energy actually does not exist, but that instead, we are being tricked by the behavior of gravity. Einstein’s Theory of General Relativity remains the possibility that it is incomplete on the very largest distance scale. Physicist have been inventing alternative theories and also trying to reconcile General Relativity with Quantum Mechanics and efforts that have given rise to String Theory, String theory holds out the intriguing possibility that part of the universe we see is highly atypical in our tiny corner of the universe. Challenges raised by Dark Matters and Dark Energy will have physicists and astronomers observing and experimenting to give us the necessary clues that explain the dark side of the universe that is Dark Matter and Dark Energy.
How will this book contribute to my success upon release:
Book son science and technology enhances my analytical and critical thinking skills. The skills will help me integrate with the new communities upon my release.
