Name: A Brief History of Everything, feat. Neil deGrasse Tyson
Uploaded: 2020-03-28T09:41:22.000Z
Duration: 8 min 30 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

"The world has persisted many a long year,

Advanced passive voice

having once been set going in the appropriate motions.

all the space, and all the matter, and all the energy of the known universe

was contained in a volume less than one trillionth the size

Conditions were so hot the basic forces of nature

that collectively describe the universe were unified.

For reasons unknown, this sub-pinpoint-sized cosmos began to expand.

When the universe was a piping-hot 10 to the 30th degrees,

and a youthful 10 to the minus 43 seconds old --

before which all of our theories of matter and space

black holes spontaneously formed, disappeared, and formed again,

out of the energy contained within the unified field.

Under these extreme conditions, in what is admittedly speculative physics,

the structure of space and time became severely curved

as it gurgled, into a spongy, foamlike form.

During these epochs, phenomena described by Einstein's general theory of relativity,

and quantum mechanics, the description of matter in its smallest scales,

As the universe continued to expand and cool,

Quickly thereafter, the strong nuclear force and the electroweak force split from each other,

which was accompanied by an enormous release of stored energy,

that induced a rapid 30-power-of-10 increase in the size of the universe.

The rapid expansion of the universe, known as the epoch of inflation,

stretched and smoothed out the cosmic distribution of matter and energy,

so that any regional variation in density

became less than one part in one hundred thousand.

Continuing onward with what is now laboratory confirmed physics,

the universe was hot enough for photons to spontaneously convert their energy

which immediately thereafter annihilated each other,

returning their energy back to the photons.

For reasons unknown, this symmetry between matter and antimatter had been broken,

which led to a slight excess of matter over antimatter.

a billion plus one matter particles were born.

This asymmetry was small, but really, really important

for the future evolution of the universe.

As the universe continued to cool, the electroweak force split

into the electromagnetic force and the weak nuclear force,

completing the four distinct and familiar forces of nature.

While the energy of the photon bath continued to drop,

pairs of matter-antimatter particles could no longer be created spontaneously

All remaining pairs of matter-antimatter particles swiftly annihilated,

leaving behind a universe with one particle of ordinary matter

for every billion photons, and no antimatter.

Had this matter-over-antimatter asymmetry not emerged,

the expanding universe would forever be composed of light an nothing else,

protons and neutrons assembled from the annihilations

Meanwhile, free-roving electrons thoroughly scattered the photons to and fro,

creating an opaque soup of matter and energy.

When the univers cooled below a few thousand degrees Kelvin,

about the temperature of fireplace embers,

to get snatched from the soup by the roving nuclei,

to make completed atoms of hydrogen, helium, and lithium,

The universe is now, for the first time, transparent to visible light,

and these free-flying photons are visible today

the universe continued to expand and cool,

as matter gravitated into this massive concentrations we call galaxies.

Between 50 and 100 billion of them formed,

each containing hundreds of billions of stars,

that undergo thermonuclear fusion in their cores.

Those stars with more than about 10 times the mass of the Sun

achieve sufficient pressure and temperature in their cores

to manufacture dozens of elements havier than hydrogen,

including elements that compose the planets and life upon them.

These element would be emarassingly useless

were they to remain locked inside the star.

But high mass stars, fortuitously, explode,

scattering their chemically enriched guts throughout the galaxy.

After seven or eight billion years of such enrichment,

an undistinguished star was born in an undistinguished region

in an undistinguished part of the universe:

During the formation of this star system,

matter condensed and accreted out of the parent cloud of gas while circling the Sun.

contained a sufficient supply of heavy elements

to form a system of planets, thousands of asteroids, and billions of comets.

For several hundred million years, the persisting impacts

of high velocity comets and other leftover debris,

rendered molten the surfaces of the rocky planets,

preventing the formation of complex molecules.

As less an less accretable matter remained in the Solar System,

Subtitles ListPlay Video

A Brief History of Everything, feat. Neil deGrasse Tyson

matter

evolve

force

split