One of the facts that are of great interest to physicists, especially astrophysicists and theoretical physicists, is the Big Bang. Of all those we study that may have existed before, there is now and there may be after such an important event in our Universe, observational cosmologists are special beings who study our universe, if history and evolution through observation of it.
All thanks to the fact that these people have played a transcendental role because of the problems they have to face and for that reason, from here, I want to pay them a small homage.
A subsection. I do not usually put equations because I see them very cumbersome and more for the one than these articles and I do not want to lose your attention, but remember that you can ask me and I will expand with all the desire. Also, I remind you that I am a little “grandfather” and I go through the branches, something that I hope will make the article more interesting.
Problems that another physicist does not find as an observational cosmologist can not repeat the experiment, can not prepare the universe so that he can re-do the experiment as many times as he wants to be able to eliminate errors, either by calculation or measurement, which Turns into brave, at the same time as tarados, to, many times have to rely on their intuition.
A clear example of what his intuition (and mathematics) has given is the discovery of dark energy (and dark matter).
The serious problem they face is, as I said, whether the data obtained are real, casual or a mere measurement problem. How to know that they are casual ?. Let’s put an example backwards a data that is a mere chance and is not a standard and therefore is the result of chance.
It is a coincidence that the Sun and the Moon are located at such a distance from the Earth that, in an eclipse, the Moon actually covers the Sun, showing its crown (and helping to study it). Come on, there is no law that makes the satellites at that distance and if a mere (fortunate) coincidence that it is on Earth. And more knowing that the Moon moves away from the Earth because it loses energy since it has to, on Earth, create tides and this … it is an energy cost. Giving more chance that, in the moment in which we live, we have such a great chance.
As I said, observational cosmologists are dedicated to seeing the development and history of our universe and among other things they do so by seeing the expansion of this universe. How do they do it ?, because through the background radiation and measuring the distance of a standard, the explosion of a type Ia supernova of which it is known that the light that emits is always the same.
The background microwave radiation, something that you have surely heard and you have seen the photo without anyone explaining it (which I am going to do now), comes from the hot universe, when it was a fat plasma ball of about 4000 degrees Celsius. And, before that, being the universe so dense, photons and certain wavelengths were unable to escape the interior of this since everything was there very tight. An example is trying to get out of a subway car, from the center part at rush hour, you get out, you get out, but you spend your time hitting people until you achieve your goal. For the universe, after the Big Bang was the same, photons and energy was unable to get out by beating because it was tight, until it expanded and cooled enough to be able to leave.
At that time, the gravity of that mass had not formed anything and therefore the distribution of matter was “more or less uniform”, emphasizing the more or less. This more or less, with the expansion culminating in different zones of pressures and densities that are the ones that have created the galaxies.
These “fluctuations” can still be measured. And you say how and why ?. I’m going to get a little scallion and I’m going to get off the tangent, but it helps explain. Something very important and that, still it is not known, is the topology of the universe, that form has. We do not know the form it actually has but if we know that the universe is homogeneous, come on, it is the same on all sides. It is known that nothing that is inside can escape from it, that is, it has no edges, that you can pull “straight” everything you want that you will not leave the universe no matter how much you walk, as in The Earth where you can walk on its surface indefinitely that you are not going to leave it since the topology is spherical (physical joke that we counted in my career times: it runs torcuaz that the topology is spherical!). It can be a sphere, flat, somewhat curved (so that if you reach the edge you follow below) or a tape of Meobius and we the ant that walks on.
Then the energy (radiation) that has escaped the Big Bang can still be measured as it is spinning even through the universe, just as light (and therefore measuring the distance of a star and its position has its complication at Not knowing if we are seeing it directly or the bounced light that has gone around the universe … curious truth?).
Ralph Alpher and Robert Herman in 1947 announced that, precisely, due to the Big Bang, there was an electromagnetic radiation (microwave) swarming around the universe and calculated it with great precision (5 Kelvin), although it was not until 1965 with Arno Penzias and Robert Wilson who had the technology to measure it showing by the dispersion in quotas of the energy that was fulfilled the Plank formula of the hollow body allowing to consider the universe as it is, a hollow body closed on itself.
The cosmic background, like all radiation, depends on the frequencies, that is, the temperature of the microwave background (remember that I use one or the other phrase for the same) depends on the temperature of the thermal radiation.
Then the anisotropies observed in the background radiation give us a lot of information about the earliest times of the universe, such as how, how radiation was released when the universe cooled, how gravity created “lumps “In the density of the soup after the Big Bang and, by size, that this period of rapid expansion was short, which shows that the universe expands or has expanded at different speeds, sometimes faster Times slower and now another fast stage.
In addition, thanks to Einstein’s equations (which has more than the famous relativity and energy) models can be made of the distribution of matter and make models of how was, is and will be the expansion of the universe.
And why does the universe expand? Well, here I go back to being a little grandpa chive, so calm down. As I think I have counted on string theory, space itself, is made up of strings (and I will not go into the simplification of quantum gravitation of loops) where, space grows the more strings are believed. The space itself, is like a sponge and admits in the certain amount of energy. If there is more energy than the one that fits in space (remember, it’s like a sponge you get more water), it grows. And if the sponge, could grow “indefinitely” we would have our universe. That is to say, in the Big Bang there was so much energy that it did not fit in the space that it housed with what the logical consequence is an expansion.
Returning to the subject of background radiation, the dispersion of the spectrum, as seen has a maximum (and a few). What is this?. The curvature of space because, gravity curves anything, even the waves of a radiation (light is, remember).
The curious fact is that the curvature of space is not always constant, it can be positive, negative or neutral (a plane) but, on our scale, space has practically no curvature, it is flat. With what, or the universe is very large (and just as on Earth we do not see the curvature of it) or the topology is not spherical.
The good thing about the image that I have put is that the peaks seem to contradict the amount of matter that exists except that there is an unknown type of energy that does not cause gravity and therefore “lumps” but is important because of the curvature That generates … and what is that type of energy? … the dark energy. That is to say that the peaks in the background radiation spectrum give us the idea of the existence of dark energy by the curvature, which things.
But not only that, the mass not attributable to dark energy is much greater than the matter we can see, so that in addition to the dark energy there is something else there, another type of energy, dark matter.
That is, from the background image of radiation have drawn some conclusions the sea of interesting.
Now, for the last time, dark matter is supposed to be a vibration of certain strings (string theory, remember) that vibrate so little that it makes them impossible to see and measure directly (for now, since we do not have The technology to see the vibration of a string … or to see it) and that does not emit radiation (or not enough to capture it), but thanks to certain observations like the polarization of background radiation we know not only that it is there Allows us to see its gravitational effects by polarizing the background radiation. This has also helped the guys at LIGO, famous for having detected gravitational waves to think that thanks to their detectors can draw ideas about the intensity of gravitational waves in remote times (Big Bang, remember) and still be able to capture them, Measure them and know how the universe worked in those times.
And if you have come here reading, you are a brave and you deserve all my respects and apologies for such a tostón that you have swallowed.