Can we see the beginning of the universe?

As I often point out in these posts, the mainstream media, and sometimes high-profile popular magazines as well, may not be quite accurate when they announce science news. With headlines, especially, they tend to make major mistakes, because they try to make them as appealing as possible, which means that they also suffer from the greatest distortions.

Let us look at a recent news. This is the headline:

Scientists figured out how to see the beginning of time

After reading the text, we can see that this news must be read in the following context:

1. The cosmic background radiation, which according to the standard cosmological model arose about 380,000 years after the Big Bang, prevents us from seeing what happened before by means of electromagnetic waves, because it acts as an opaque screen for these waves. This means that we cannot directly “see” what happened in the first 380,000 years of the history of the universe, although we can infer it by applying Friedman’s cosmological equations, which are based on Einstein’s general theory of relativity. I have put the word “see” in quotation marks, because this limitation not only applies to light waves, captured by optical telescopes, but also to infrared, ultraviolet, X-ray and gamma-ray telescopes, as well as radio telescopes, that work with microwaves.
2. The matter of the universe, when its age was less than 380,000 years, was not made by atoms in the gaseous state, but in a state of plasma, i.e., by atoms devoid of the electronic shell and made of nuclei. On the other hand, the electrons were loose. Plasma is opaque to electromagnetic waves. That is why we cannot “see” what is inside the sun, nor what was there before the cosmic background radiation.
3. The Princeton University team behind this news has devised a procedure that could be used to penetrate a little deeper into the unknown zone of the universe, by using gravitational waves. As those waves are not electromagnetic, gravitational waves are not affected by the opacity of the plasma. Perhaps a new type of telescope could be designed that uses these waves to penetrate the plasma behind the cosmic background radiation.
4. In any case, we must remember that research on the detection of gravitational waves is in its infancy. These waves, which were announced by Einstein applying the general theory of relativity, were not detected until 2015, a century after their prediction. Therefore, we are talking about a hypothetical design that would require considerable technological advances. This is not something that will happen tomorrow.

The news in question ends like this: the researchers say they can use ripples in space-time, known as gravitational waves, to basically see the start of everything we know.

But things are not that easy. Perhaps we may detect something of what happened during the first 380,000 years of the history of the universe, which until now was beyond our reach. But calling that lapse of 380,000 years the start of everything we know looks like hype.

The same post in Spanish

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Manuel Alfonseca