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So I will talk about Neutrinos. I will try to explain that

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these are particles with really curious and different properties

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compared to the other particles known so far.

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Particle physics is able to answer to questions like:

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what are we made of? what are animals made of?

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So, these walls of this building, the stars, everything

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is made up by a small quantity of few ingredients.

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Only a few elements are needed in order to explain what everything is made of.

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So, there are quarks, that exchange gluons among them.

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Gluons are only exchanged among quarks.

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There are electrons that exchange photons among them and with

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the quarks because they are all charged.

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So, what we may be asking ourselves is: Is that it?

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Is this everything the Universe is made of?

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Well, it is everything we can easily see but

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there are more things in the Universe, particularly neutrinos.

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And there are a lot of neutrinos in the universe:

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ten billion for each quark or electron.

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They are everywhere and have diverse origins.

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For instance, in each cubic centimetre of the universe

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(in a little cube with a side of 1cm) there are

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300 neutrinos approximately.

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Neutrinos were produced in the first stages of the Universe,

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they are vestiges of the Big Bang that are still wandering arround:

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300 in each cubic centimetre.

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By its nature, our bodies produce hundreds of thousands of neutrinos each day.

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Here we have an intern, that probably lives under poor conditions,

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and that is continually producing neutrinos without noticing,

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hundreds of thousands of neutrinos each day.

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But actually, the Sun, is one of the most productive sources

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of the neutrinos around us. The Sun produces considerably

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more neutrinos than the unfortunate intern.

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Specifically, 100 trillion neutrinos that

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come from the sun  go through us and through the

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unfortunate intern each second without being noticed.

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The question then is, if there are so much neutrinos everywhere

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produced by the Sun and also by ourselves without realizing about it,

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being these neutrinos in each cubic centimeter,

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How is it possible that it took us so long to discover them? Why can't we feel them?

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The fact is that, even though there are tons of them,

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they behave as if they were ghosts, that is why they seem to be invisible.

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They are able to go through matter without interacting with it,

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without changing and without altering the matter they go through.

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Ir order to have an idea, from all of these trillions of neutrinos that

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come from the sun and that go through us each second,

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only one out of every 100 quintillions (of

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those who go through us) interacts with us,

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and this few that achieve interaction with us

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posses such a tiny mass and so low an energy

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that it is impossible for us to perceive them.

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Excerpt from the conference held

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November, 14th, 2013, at the Residencia de Estudiantes,

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during the sessions "La frontera de la Física Fundamental".

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Full video available at: www.eddaddeplata.org