Quotes About Spacetime

The functions filled spacetime and they pierced his soul. Exhilarated, he rode their gaudy brilliance through the hearts of aging stars.

time and space are intertwined. It is something like adding a fourth direction of future/past to the usual left/right, forward/backward, and up/down. Physicists call this marriage of space and time "space-time," and because space-time includes a fourth direction, they call it the fourth dimension.

region of space-time known as a black hole.

bosons—photons, and so on— are in some respects strongly tied to spacetime. Their wavelengths expand as the universe expands.

So either closed timelike curves can't exist, or big macroscopic things can't travel on truly closed paths through spacetime—or everything we think we know about thermodynamics is wrong.

not a conclusion we derive from deeper principles. Straight lines in space are the shortest possible distance; straight paths in spacetime are the longest possible time.

a straight line through spacetime, if you like—is the path of longest time between two events.

Extraneous motion decreases the time elapsed between two events in spacetime, whereas it increases the distance traveled between two points in space.

Obviously the correspondence needs to be nonlocal; you can't match up individual points in a four-dimensional space to points in a five-dimensional space. But you can imagine matching up states in one theory, defined at some time, to states in the other theory. If that doesn't convince you that spacetime is not fundamental, I can't imagine what would.

Jaroslav Trnka, this discovery implies that spacetime, if not entirely illusory, is not fundamental: it is the result of geometrical relationships at a deeper level (Arkani-Hamed 2012; Trnka 2013). Henceforth physicists can

Gravity on this view is no longer so much a thing as an outcome—"not a 'force' but a byproduct of the warping of spacetime," in the words of the physicist Michio Kaku, who goes on: "In some sense, gravity does not exist; what moves the planets and stars is the distortion of space and time.

This is gravity—a product of the bending of spacetime.

why doesn't the universe spin?

Physicists traced the failure to the jitters of quantum uncertainty. Mathematical techniques had been developed for analyzing the jitters of the strong, weak, and electromagnetic fields, but when the same methods were applied to the gravitational field-a field that governs the curvature of spacetime itself-they proved ineffective. This left the mathematics saturated with inconsistencies such as infinite probabilities.

each of the bubble universes appears to have finite spatial extent when examined from the outside, but infinite spatial extent when examined from the inside.

all events making up the history of the universe are on view; they are all there, static and unchanging. Different observers don't agree on which of the events happen at the same time—they time-slice the spacetime loaf at different angles—but the total loaf and its constituent events are universal, literally.

You have to get old because of the geometry of spacetime.

So: if you buy the notion that reality consists of the things in your freeze-frame mental image right now, and if you agree that your now is no more valid than the now of someone located far away in space who can move freely, then reality encompasses all of the events in spacetime.

True time is four-dimensional.

In short, given continuous spacetime, there are a second-order infinity of possible histories of the biosphere.

What you or I would recognize as an alien invasion by tentacled horrors from beyond spacetime Angleton would see as a teachable moment.

The notion of "the present" refers to things that are close to us, not to anything that is far away. Our "present" does not extend throughout the universe. It is like a bubble around us.

Quanta of space mingle with the foam of spacetime, and the structure of things is born from reciprocal information that weaves the correlations among the regions of the world.

quantum mechanics cannot deal with the curvature of spacetime, and general relativity cannot account for quanta. This is the problem of quantum gravity.