Example sentences of "at the present epoch " in BNC.
Next page| No | Sentence |
|---|---|
| 1 | The predicted correlation function of temperature inhomogeneities can be expressed in terms of the power spectrum of density fluctuations as where C l is the angular power spectrum of temperature fluctuations and P ( k , ) is the power spectrum of density fluctuations at the present epoch . |
| 2 | Angular scales , on the microwave background can be related to linear scales , λ , at the present epoch by . |
| 3 | We convert the data to a quantity related to the power spectrum at the present epoch , the fractional variance in density per ln k ( refs 20 , 21 ) |
| 4 | We have calculated the power spectrum at the present epoch , using COBE , QDOT and the bulk-flow measurements , and compared it with a range of cosmological models : ( 1 ) adiabatic cold dark matter ( CDM ) , ( 2 ) adiabatic hot dark matter ( HDM , for one stable massive neutrino species ) , ( 3 ) warm dark matter , ( 4 ) isocurvature CDM , ( 5 ) texture plus CDM , ( 6 ) CDM plus vacuum energy density , and ( 7 ) CDM plus HDM ( one stable neutrino species ) . |
| 5 | But we know that there must have been some irregularities , because otherwise the matter in the universe would still be perfectly uniformly distributed at the present epoch , instead of being clumped together in stars and galaxies . |