Dimensions
Accuracy
grantno: AC02-76CH03000
osti: 15011776
Fermi National Accelerator Laboratory
Dark energy could actually be the manifestation of a modification to the Friendmann equation arising from new physics (e.g., extra dimensions). Writing the correction as (1 - {Omega}{sub M})H{sup {alpha}}/H{sub 0}{sup {alpha}-2}, they explore the phenomenology and detectability of such. They show that: (1) {alpha} must be {approx}< 1; (2) such a correction behaves like dark energy with equation-of-state w{sub eff} = -1 + {alpha}/2 in the recent past (10{sup 4} > z >> 1) and w = -1 in the distant future and can mimic w < -1 without violating the weak-energy condition; (3) w{sub eff} changes, dz/dw|{sub z {approx} 0.5} {approx} {Omicron}(0.2), which is likely detectable; and (4) a future supernova experiment like SNAP that can determine w with precision {sigma}{sub w}, could determine {alpha} to precision {sigma}{sub {alpha}} {approx} 2{sigma}{sub w}.
71 Classical And Quantum Mechanics, General Physics
Modifications
/Chicago U., Astron. Astrophys. Ctr. /KICP, Chicago /Chicago U., EFI /Fermilab
2003-01-01
Dvali, Gia
ark: ark:/67531/metadc1409385
Turner, Michael S.
United States. Department of Energy.
rep-no: FERMILAB-PUB-03-040-A
11 pages
Dark energy as a modification of the Friedmann equation
Physics
U., /New York