Fear of a Black Universe: An Outsider's Guide to the Future of Physics by Stephon Alexander

Author:Stephon Alexander [Alexander, Stephon]
Language: eng
Format: epub
Tags: science, Chaotic Behavior in Systems, Space Science, Cosmology, Physics, Gravity
ISBN: 9781541699632
Google: -xHYzQEACAAJ
Publisher: Basic Books
Published: 2021-11-15T23:45:26.332915+00:00

9

COSMIC VIRTUAL REALITY

The ancient idea that the universe was created from a state of emptiness is captured poetically in the book of Genesis: “And the world was without form and void, and darkness was on the face of the deep. And God said, Let there be light, and there was light.”

Similar sentiments were expressed earlier in ancient Babylonian, Sumerian, West African, and Maori creation philosophies. Our precision physics of quantum field theory and general relativity combine to give a picture of the early universe that resonates with these creation stories—the idea that everything emerged from the void. The notion of emptiness, of blackness, according to modern physics, is not how we imagine it to be based on our direct experience of empty space. In every region of empty space, quantum fields are seething with activity so rapid that our ordinary-day perceptions are blind to it. But empty space is much more interesting that our psychological and cultural projections make it to be. The modern picture of the early universe is that the ignition of the big bang emerged from a previous primordial state in which the world was devoid of matter in a vacuum state. My goal here is not to turn our discussion into one of a perennial matter but to motivate the underlying physics that presently attempts to explain the creation of the physical universe from an empty state during the big bang epoch, and discuss some current mysteries cosmologists face.

To date, the most accepted and experimentally compelling paradigm of the early universe is cosmic inflation. The critical message of inflation is that every bit of structure in the universe, including planets and living things, emerged from quantum fluctuations from a vacuum state that contains the inflaton field’s potential energy—the inflaton is called that because it drives inflation—and nothing else. Nevertheless, what physicists call virtual particles can emerge spontaneously from the vacuum, and these are important to explaining how both matter and large-scale cosmic structure emerged from nothing. And although there are alternatives to cosmic inflation, such as the big bounce and cyclic cosmologies, which attempt to alleviate the problems that plague inflation (we will discuss some of these alternatives in the next chapter), none of them are free from the influence of virtual particles. No matter which way we slice it or which model we prefer, the idea that all matter and structure in the universe came from virtual quantum processes is inescapable, counterintuitive, and requires a more in-depth examination. After all, nature has to figure out how to make virtual particles real particles. And indeed cosmic inflation has a clever trick up its sleeve to make this happen.

In quantum field theory, virtual processes are ubiquitous and have been measured in the lab. A consequence of these virtual processes are virtual particles, which are particles that quickly materialize and disappear into the vacuum before having any material consequences. The vacuum is not empty but seething with rapid interactions of quantum fields and particles. Remember that quantum fields comprise oscillator modes that vibrate in the vacuum state.

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