A first challenge to the readers:

What is wrong in the following reasoning?

Photons have no real mass or rest mass. In spite of this, photons are influenced by gravitation. Light bends off, passing the sun.

In astronomy literature we can read, that Einstein was the one, who predicted this. That is not quite true. Already in the 1700 Laplace predicted this. If we calculate with Newton’s law of gravity, we find that all particles bend off with the same angle, when passing the sun, irrespective of their mass. Also particles with zero mass.

Einstein showed however, that photons or light, due to his theory, bend off exactly double as much. Measurements have shown that Einstein was right.

When photons pass the sun, the momentum of the photons changes.

As the sum of momentum is constant, the momentum of the sun is changed. So the photons influence ordinary matter by gravitation.

This is in line with Einstein’s statement, that energy packages influence by gravitation.

Our knowledge about neutrinos is far from complete. It is often discussed, if they have a rest mass or not.

When there was a supernova explosion, 170 000 light-years away, both electromagnetic radiation and neutrinos were detected. The arrival of the two types of physical signals was less than 18 hours apart. They probably were not emitted at the same time. The collapse and the explosion of the star take some time.

So neutrinos travel with a speed of more than 0. 999 999 99 of the speed of light. (With this speed, the mass of a particle is 7 000 times larger than the rest mass.) So it is very probable, that neutrinos travel with the speed of light.

Nothing can travel with the speed of light, if having a real mass or rest mass.

So it is much more probable, that

Recent evaluations of some measurements of redshift of distant objects are said to prove that neutrinos have mass. Some other scientists however, doubt the theories behind that.

Light can be described either as a stream of photons or as a wave. Photons can be described as having a "wave pattern" (the EM-radiation).

It is also said that other particles, as electrons, can be described as having a "wave pattern".

So it is logical to assume, that also neutrinos can be described as having a "wave pattern", even if we don’t know what type of waves.

If photons and neutrinos have properties alike - both particle character and wave pattern, no rest mass and a speed equal to the speed of light - then it is logical to assume, that

The above logical conclusions: that neutrinos act as photons in this case and that photons both are influenced by gravitation and influence by gravitation, lead to the logical conclusion, that

This is in line with Einstein’s statement, that energy packages influence by gravitation.

The assumption that neutrinos without mass do not influence by gravitation is not in agreement with Einstein’s statement.

There are several reasons to believe, that there is an unknown or dark matter in our Universe. One of the best candidates to explain the dark matter is the neutrino.

We found it logical to assume, that neutrinos are influenced by gravitation and that neutrinos influence by gravitation, even though they have no mass.

So it is logical to assume, that

 The number of neutrinos in the Universe and their energy is uncertain. Some estimations, however, give values, that agree with the assumptions above.