What is most influential candidate quantum cosmology today?

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The discussion centers on the most influential candidate in quantum cosmology, specifically between string theory-inspired models and loop quantum cosmology (LQC). It highlights that LQC has gained prominence since 2007, effectively reproducing known observations like the Friedmann–Robertson–Walker equation. While LQC is noted for its potential predictions regarding the cosmic microwave background (CMB), questions remain about whether string theory can also provide similar predictions. The conversation acknowledges that string theory has historically received more citations and funding, despite LQC's claims of making falsifiable predictions. Overall, the debate reflects a shift in focus within the field, with LQC emerging as a significant contender.

What is the most influential candidate quantum cosmology today?

  • string theory inspired scenarios (i.e ekpyrotic brane collisions)

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  • other (please specify)

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ensabah6
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What is the most influential candidate quantum cosmology today?

By influential it (a) reproduces known observation, (b) offers speculative ideas in the Planck epoch, (c) professionally researched and published in peer-reviewed journals. I suppose the time line should be 2007-2009

The two I am aware of are string theory inspired braneworld and ekpyrotic brane collisions and loop quantum cosmology.

Is it true that loop quantum cosmology reproduces known observation, including Friedmann–Robertson–Walker equation, and is string theory inspired quantum cosmologies able to do so?

From what I've heard, prior to 2007, quantum cosmology was dominated by string theory but after 2007 it has been dominated by loop quantum cosmology.

It is hoped LQC may make predictions on CMB. Can string theory quantum cosmology also make such predictions?

While LQC is a symmetry-reduced version of LQG, and makes assumptions like homogeneity and isotropy, the Friedmann–Robertson–Walker equation makes the same assumptions, and is in general agreement with observation.If there is a third please write-in, thanks.
 
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I am not qualified to answer this and lean more towards LQG but I think String has more citations and funding. I have heard many sting theorists, like susskind, dance around how string theory can be tested. whereas rovelli and smolin say they are making falsifiable claims and give examples. I think string "culture" is still the most prominent though waning.
 
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