Quotes About Universe

They imply that a region of space the size of a pea would be stretched larger than the observable universe in a time interval so short that the blink of an eye would overestimate it by a factor larger than a million billion billion billion.

Dutifully following the second law, we conclude that today's state derives from yesterday's even lower entropy state. And that state, we envision, derives from the day-before-yesterday's still lower entropy state, and so on, yielding a trail of ever-decreasing entropy taking us ever farther back in time until we finally reach the big bang.

if you know the quantum wavefunction right now for every particle in the universe, Schrödinger's equation tells you how the wavefunction was or will be at any other moment you specify. This

In the Inflationary Multiverse, our universe could well be an island oasis in a gigantic but largely inhospitable cosmic archipelago.

Remember from Chapter 7 that in the Many Worlds framework, every potential outcome embodied in a quantum wavefunction—a particle's spinning this way or that, another particle's being here or there—is realized in its own separate, parallel universe. The universe we're aware of at any given moment is but one of an infinite number in which every possible evolution allowed by quantum physics is separately realized.

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Then, just as two trees are the same age if they have the same number of tree rings, and just as two samples of glacial sediment are the same age if they have the same percentage of radioactive carbon, two locations in space are passing through the same moment in time when they have the same value of the inflaton field. That's how we set and synchronize clocks in our bubble universe.

so, with only finitely many different particle arrangements, the arrangements of particles within patches must be duplicated an infinite number of times. That's the result we've been after.

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.

Solving problems, learning how the universe is put together-that's what had always captivated me.

In the far reaches of an infinite cosmos, there's a galaxy that looks just like the Milky Way, with a solar system that's the spitting image of ours, with a planet that's a dead ringer for earth, with a house that's indistinguishable from yours, inhabited by someone who looks just like you, who is right now reading this very book and imagining you, in a distant galaxy, just reaching the end of this sentence.

turn the earth into a black hole you'd need to squeeze it down to about two centimeters across;

If string theory is right, the microscopic fabric of our universe is a richly intertwined multidimensional labyrinth within which the strings of the universe endlessly twist and vibrate, rhythmically beating out the laws of the cosmos.

So, whereas Bohr argued away by fiat all but one outcome in a measurement, the Many Worlds approach, combined with decoherence, ensures that within each universe it appears as though the other outcomes have vanished. Within each universe, that is, it's as if the probability wave has collapsed. But, compared with the Copenhagen approach, the as if provides for a very different picture of the expanse of reality. In the Many Worlds view, all outcomes, not just one, are realized.

But when we examine the universe, there seem to be numerous lost opportunities, since there are many things that are more ordered than they have to be.

The uncertainty principle tells us that the universe is a frenetic place when examined on smaller and smaller distances and shorter and shorter time scales.

by the time the universe was a couple of minutes old, it was filled with a nearly uniform hot gas composed of roughly 75 percent hydrogen, 23 percent helium, and small amounts of deuterium and lithium. The essential point is that this gas filling the universe had extraordinarily low entropy. The big bang started the universe off in a state of low entropy, and that state appears to be the source of the order we currently see. In other words, the current order is a cosmological relic.

Just as important, the energy released by the inflaton field isn't lost-instead, like a cooling vat of steam condensing into water droplets, the inflaton's energy condenses into a uniform bath of particles that fill space. This two-step process-brief but rapid expansion, followed by energy conversion to particles-results in a huge, uniform spatial expanse that's filled with the raw material of familiar structures like stars and galaxies.

At the ultramicroscopic level, the universe would be akin to a string symphony vibrating matter into existence.

I used to imagine that by studying the universe, by peeling it apart figuratively and literally, we would answer enough of the how questions to catch a glimpse of the answers to the whys.

Religion is not meant to explain the universe. It cannot replace scientific research.

As the amount of matter used to create a black hole increases, the required density to which that matter must be crushed decreases.

Current data thus favor an ever-expanding universe shaped like the three-dimensional version of the infinite tabletop or of the finite video-game screen.

For now, we will simply assume that one way or another, the early universe transitioned into this low-entropy, highly ordered configuration, sparking the bang and allowing us to declare that the rest is history.