Ovidio Universe: The Beginning to the End of the Universe: Exploring the shape of space-time

April 22, 2021

The Beginning to the End of the Universe: Exploring the shape of space-time

The afterglow of the Big Bang reveals the geometry of the universe.


Einstein’s field equations describe gravity not as a force, but rather a property of space-time — the fabric of the universe. Earth travels around the Sun in a circular orbit because the Sun’s mass deforms the space-time around it like a bowling ball on a trampoline.

In ancient times, scholars such as Aristotle thought that heavy objects would fall faster than lightweight objects under the influence of gravity. About four and a half centuries ago, Galileo Galilei decided to test this assumption experimentally. He dropped objects of different masses from the Tower of Pisa and found that gravity actually causes them all to fall the same way. More than 300 years later, Albert Einstein was struck by Galileo’s finding. He realized that if all objects follow the same trajectory under gravity, then gravity might not be a force but rather a property of space-time — the fabric of the universe, which all objects experience in the same way.

In one of the most important advances in modern physics, Einstein recognized that when space-time is curved, objects do not follow straight lines. He reckoned that Earth, for example, orbits the Sun in a circle because the Sun curves space-time in its vicinity. This is similar to the path of a ball on the surface of a trampoline whose center is weighed down by a person.

In November 1915, Einstein published the mathematical equations that established the foundation for his general theory of relativity. These equations describe the link between matter and the space-time in which it resides, showing that mass deforms space-time and influences the path of matter. In the words of physicist John Wheeler: “Space-time tells matter how to move and matter tells space-time how to curve.”

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Black Holes and Wormholes FAQ

1 - What is a wormhole?

Wormholes are tunnels in space-time that can theoretically allow travel anywhere in space and time, or even into another universe. In many ways, wormholes resemble black hole.

2- How is wormhole created?

In principle, building a wormhole is pretty straightforward. According to Einstein's Theory of General Relativity, mass and energy warp the fabric of space-time. And a certain special configuration of matter and energy allows the formation of a tunnel, a shortcut between two otherwise distant portions of the universe

3- Is a wormhole possible?

A physicist has shown that wormholes can exist: tunnels in curved space-time, connecting two distant places, through which travel is possible.

4- Can black holes be wormholes?

From the outside, wormholes can appear similar to black holes. But while an object that falls into a black hole is trapped there, something that falls into a wormhole could traverse through it to the other side. No evidence has been found that wormholes exist

Baryon Matter

Baryon matter is the foundation that 
constitutes every body and object in 
our Universe. 
To better understand how it is structured, 
it is necessary to refer to the classification 
scheme  of the Standard Model as it has 
been structured over the last century.  
The Standard Model predicts that matter 
is basically the product of two types of
particles,light ones,leptons, and heavy ones, 
baryons. 
Both terms derive from the Greek. 
While leptons are truly fundamental particles, 
i.e. not further divisible into other particles, 
baryons are aggregates of other elementary 
particles such as leptons, quarks that are 
endowed with fractional charge,
 i.e. a fraction of the charge of an electron.

Light Year

The light-year is a unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometres (9.46×10¹² km) or 5.88 trillion miles (5.88×10¹² mi).As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days).Because it includes the word "year", the term light-year may be misinterpreted as a unit of time.

The light-year is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist contexts and popular science publications.

1 light-year	= 9460730472580800 metres (exactly)
	≈ 9.461 petametres
	≈ 9.461 trillion kilometres (5.879 trillion miles)
	≈ 63241.077 astronomical units
	≈ 0.306601 parsecs

What is the antimatter

The antimatter is missing – not from CERN, but from the Universe! At least that is what we can deduce so far from careful examination of the evidence. For each basic particle of matter, there exists an antiparticle with the same mass, but the opposite electric charge. The negatively charged electron, for example, has a positively charged antiparticle called the positron. When a particle and its antiparticle come together, they both disappear, quite literally in a flash, as the annihilation process transforms their mass into energy.

The evidence spoke for itself

The ‘case file’ of antimatter was opened in 1928 by physicist Paul Dirac. He developed a theory that combined quantum mechanics and Einstein’s special relativity to provide a more complete description of electron interactions. The basic equation he derived turned out to have two solutions, one for the electron and one that seemed to describe something with positive charge (in fact, it was the positron). Then in 1932 the evidence was found to prove these ideas correct, when the positron was discovered occurring naturally in cosmic rays.

For the past 50 years and more, laboratories like CERN have routinely produced antiparticles, and in 1995 CERN became the first laboratory to create anti-atoms artificially. But no one has ever produced antimatter without also obtaining the corresponding matter particles. The scenario should have been the same during the birth of the Universe, when equal amounts of matter and antimatter would have been produced in the Big Bang.

“Just one more thing…”

So if matter and antimatter annihilate, and we and everything else are made of matter, why do we still exist? This mystery arises because we find ourselves living in a Universe made exclusively of matter. Didn't matter and antimatter completely annihilate at the time of the Big Bang? Perhaps this antimatter still exists somewhere else? Otherwise where did it go and what happened to it in the first place?

Such questions have led to speculative theories, from a break in the rules to the existence of an entire anti-Universe somewhere else! The way to solve the baffling disappearance of antimatter, and to learn more about this substance in general, is by studying both particles and antiparticles to find and decipher the subtle clues.