Ovidio Universe: The Cosmic Microwave Background

January 05, 2021

The Cosmic Microwave Background

The Cosmic Microwave Background (CMB) is a snapshot of the oldest light in our cosmos, imprinted on the sky when the Universe was just 380 000 years old. It shows tiny temperature fluctuations that correspond to regions of slightly different densities, representing the seeds of all future structure: the stars and galaxies of today.

The top view shows anisotropies in the temperature of the CMB at the full resolution obtained by Planck. In the middle view, the temperature anisotropies have been filtered to show mostly the signal detected on scales around 5º on the sky. The lower view shows the filtered temperature anisotropies with an added indication of the direction of the polarised fraction of the CMB.

A small fraction of the CMB is polarised – it vibrates in a preferred direction. This is a result of the last encounter of this light with electrons, just before starting its cosmic journey. For this reason, the polarisation of the CMB retains information about the distribution of matter in the early Universe, and its pattern on the sky follows that of the tiny fluctuations observed in the temperature of the CMB.

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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.