scholarly journals A Cyclic Model of the Universe

Science ◽  
2002 ◽  
Vol 296 (5572) ◽  
pp. 1436-1439 ◽  
Author(s):  
P. J. Steinhardt
Keyword(s):  
2008 ◽  
Vol 23 (01) ◽  
pp. 33-36 ◽  
Author(s):  
LAURIS BAUM ◽  
PAUL H. FRAMPTON

Following up a recent proposal1 for a cyclic model based on phantom dark energy, we examine the content of the contracting universe (cu) and its entropy S cu . We find that beyond dark energy, the universe contains on average zero or an unlikely single photon which if present immediately after turnaround would have infinitesimal energy that blue shifts eventually to produce e+e- pairs. These statements are independent of the equation of state ω = p/ρ of dark energy provided ω < -1. Thus S cu = 0 and if observations confirm ω < -1, the entropy problem is solved. We discuss the absence of a theoretical lower bound on ϕ = |ω+1|, then describe an anthropic fine tuning argument that renders unlikely extremely small ϕ. The present bound ϕ ≲ 0.1 already implies a time until turnaround of (tT - t0) ≳ 100 Gy.


Author(s):  
Krzysztof Bolejko ◽  
Andrzej Krasinski ◽  
Charles Hellaby ◽  
Marie-Noelle Celerier
Keyword(s):  

2009 ◽  
Author(s):  
Ernst Heinrich Philipp August Haeckel ◽  
Joseph McCabe

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