What is the shape of the universe: flat, spherical or saddle-like?

What does the universe look like? The question itself doesn’t seem to make much sense..

If, as NASA says, the universe is simply everything, including all space and all the matter and energy it contains, and even time itself, Does everything have a shape?

If you are reading this article, you must be one of those who are willing to contemplate the unimaginable, visualize the unimaginable and spy the impenetrable.

In other words, act like a cosmologist, one of those theorists who tries to come up with credible and sustainable ideas about space that have occupied thinkers for centuries.

For them, the shape of the universe is a serious matter, because it implies the future of the cosmos: depending on what it is, we will know whether it will expand forever or reverse its expansion in a catastrophic event. Big bang, o Major implosion or collapse.

Furthermore, knowing the answer to the question asked provides clues as to whether the universe is infinite or finite.

So, How do you begin to solve this riddle?

With Albert Einstein.

The idea that space had form arose with the general theory of relativity of 1915.

And of all the forms we can think of, this alone allows the universe to take one out of three:

One of the factors that determine what form it takes is its densitythat is, the amount of matter in a given volume of space.

If it is too large, the force of gravity will be greater than the force of expansion and it will bend into a sphere.

In that case, the universe would be finite even if there were no end to it (just as the surface of a ball is not infinite, but there is no point on the sphere that can be called ‘end’).

Besides being finite, which is the scenario where the expansion will stop at some point, instead of moving away from each other, the galaxies will start growing closer together until What started with a big bang ended with a major collapse.

In the other two cases, the hyperbolic and the planar, the universe is infinite and will expand forever.

To determine what it is like (and the future of the cosmos!), solid observational evidence was needed… but of what?

Well, something wonderful.

The oldest light

What cosmologists did was measures cosmic microwave background radiationcold remains of the Big Bang or great explosion about 13.8 billion years ago.

Those traces of the creation of matter, space and time are easy to find according to the standard cosmological model, says physicist and author Marcus Chown, because they are literally everywhere.

“If you take a cubic centimeter of empty space anywhere in the universe, it contains 300 photons, light particles of this radiation.

“In fact, 99% of all light in the universe is not that of stars or anything like that, but the glow of the Big Bang”.

It was something discovered in 1965 and it looks like a photo of the newborn cosmos.

“It is the oldest light and when we capture it with our telescopes we look as far back as possible.

‘Encoded in this light is a picture of the universe as it looked a third of a million years after the Big Bang, a crucial point, as it was when the first structures, the seeds of galaxies, were formed.’

Such radiation remnants are often described as the cosmologist’s Rosetta Stone for deciphering the past, allowing researchers to draw detailed conclusions from the scant observational evidence.

How can so much be deduced from the fossil radiation of the Big Bang?

Do what some have described the most difficult measure of science.

That light from the Big Bang that is now visible in a sphere around the Earth is in the form of very short waves, microwaves, and is a mixture of light and residual heat, extremely weak, but sufficient to indicate powerful ideas.

It’s like “a uniform layer with a nearly constant temperature of about 3 degrees above absolute zero (−273.15 °C),” theoretical astrophysicist Dave Spergel explained to the BBC.

The interesting thing is in the ‘almost’.

“The minor variations are at the level of 100 thousandths of a degree from one place to another.”

They measured that, well”When we look at the microwave background, we learn about the geometry of the universesaid a person known for his work with NASA’s WMAP probe, launched in 2001 with the mission to study the air and measure these temperature differences.

It was one of many studies that helped determine the shape of the universe.

But how can observations of light particles from the Big Bang help astrophysicists like Carlos Frank of the University of Durham determine what shape it is?

“That’s the beauty of science. We can make very important inferences based on very detailed data.

“These light particles traveled for billions of years until they reached our telescopes, following any curvature.”

Depending on how they arrive, you’ll know what their journey was like.

AND?

Imagine those cosmic microwaves as two beams of light.

In a flat universe they will always remain parallel.

In a spherical universe they will travel along the curvature of space and eventually meet.

In a hyperbolic universe the rays will never cross and become increasingly separated.

And it turns out that they remain parallel.

The first time the shape and fate of the cosmos were inferred with certainty from observations was in 2000, when an international team of astronomers from Italy, Britain, the US, Canada and France, known as the Boomerang collaboration, published results of their research.

“I think this is the moment we will remember in the textbooks when we said that our universe is flat, we won’t go into a major collapse, we don’t have a limited amount of timewhich will expand forever,” they said.

Those results were later confirmed with data collected by NASA’s WMAP probe, the European Space Agency’s Planck spacecraft and measurements taken with the Atacama Cosmology Telescope.

Evidence for the flatness of the universe also emerges from studies of what is known as the critical density, which shows that the density is just below it, meaning it is flat and will expand indefinitely.

And another way to find evidence is through the isotropic line: if it’s flat, it looks the same from all angles. The JoResearch has shown that this is the case with an accuracy margin of 0.2%.

Yet we cannot rule out the possibility that we live in a spherical or hyperbolic world..

Although all measures are taken, there is always the possibility that what has happened to us for centuries with the Earth: on the scale that could be observed, the curvature was too small to observe, so it was assumed to be flat.

The larger a sphere or saddle is, the flatter each small part of it.

So it remains possible that, since the universe is extremely large, the part we can observe is so flat that its curvature can only be detected by super-precise instruments that we have not yet invented.

However, at this time Everything seems to indicate that the cosmos is flat, expanding and infinite..

The beauty of this world is that the answers often raise more questions… how can it expand if it is infinite? and how can it be infinite if it had a beginning?

We leave it at that so that we have nothing more to think about. (JO)