Observing trans-Planckian ripples in the primordial power spectrum with future large scale structure probes

We revisit the issue of ripples in the primordial power spectra caused by trans-Planckian physics, and the potential for their detection by future cosmological probes. We find that for reasonably large values of the first slow-roll parameter ǫ ( > ∼ 0.001), a positive detection of trans-Planckian ripples can be made even if the amplitude is as low as 10. Data from the Large Synoptic Survey Telescope (LSST) and the proposed future 21 cm survey with the Fast Fourier Transform Telescope (FFTT) will be particularly useful in this regard. If the scale of inflation is close to its present upper bound, a scale of new physics as high as ∼ 0.2 MP could lead to observable signatures. Observing trans-Planckian ripples 2