Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: What can we learn by probing Trans-Planckian physics   In this talk we address the issue of how the observables in our present
Universe are affected by processes that may have occured at superplanckian
energies (referred to as the {\it transplanckian regime}). For example, the
origin of the cosmological perturbation spectrum. We model the transplanckian
regime by introducing a 1-parameter family of smooth non-linear dispersion
relations which modify the frequencies at very short distances. For this family
of dispersions, we present the exact solutions and show that the CMBR spectrum
is that of a (nearly) black body, and that the adiabatic vacuum is the only
choice for the initial conditions. A particular feature of the family of
dispersion functions chosen is the production of ultralow frequencies at very
high momenta $k$ (for $k>M_P$). Modes with ultralow frequencies equal or less
than the current Hubble rate are still frozen today. Therefore, their energy
today provides a strong candidate for the dark energy of the Universe.

27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph