Features of gravitational interaction as the basis of “Dark Energy” in the gas of null strings

Abstract

In this work, the influence of the shape of the null strings that form the gas on the gravitational properties and evolution of the null string gas was investigated. An interesting result of the study is that the test null string, being in the interaction zone, can only have a shape that exactly repeats the shape of the source string. As a result, null strings having different spatial forms can be located in the gas only outside the zone of interaction with each other. The “size” (width) of the zone of interaction of each null string in the gas is determined by the value of its initial momenta, and for some critical values it can occupy the entire space. The size (width) and “impenetrability” of the interaction zones for null strings having different spatial shapes can be a physical source of “strong” gravitational repulsion in the gas of null strings. In turn, the “strong” gravitational repulsion between null strings with different spatial shapes can be a source of a long-term accelerated expansion of such a gas (a source of “dark energy”).

Thin tubes of a massless scalar field as a possible source of dark energy

“…As already mentioned in section 3, in work [70] the influence of the gravitational field of a thin tube of a massless scalar field (source string), the quadratic form of which is determined by equalities (1)-( 4), on the motion of a test null string was studied. The study showed that each tube of the scalar field has its own zone of interaction.…”

“…Moreover, for some values of these constants, the 'width' (size) of the interaction zone of one thin tube of a scalar field can occupy the entire space. An important result obtained by [70] is that only strings (thin tubes) that have the same spatial shapes can be found inside the interaction zone. In other words, thin tubes of a scalar field, which have different spatial shapes, can only be located in a gas outside the zone of interaction with each other.…”

“…In this paper, the source of the gravitational field is an axially symmetric, closed, thin tube of a massless scalar field, which moves without changing its shape and size. The quadratic form corresponding to this type of motion of a thin tube of a scalar field in a cylindrical coordinate system x 0 = t, x 1 = ρ, x 2 = θ, x 3 = z, can be represented as [68,70]:…”

“…In [68,70], an example of the functions α(q) and f(η) is given, which, together with the constants a 0 and ν 0 , must satisfy the conditions ( 31)- (36):…”

“…To substantiate the thesis about the homogeneity and isotropy of such a gas, the following can be said. When studying the motion of a test null string in a gravitational field, the source of which was a thin tube of a massless scalar field (source string), it was shown (see [70,72,73]) that the gravitational interaction of such objects has a peculiarity. Namely, there is always only a 'narrow' region (interaction zone), and only being inside this region can the test null string interact with the source string.…”