#theoretical-cs

1 messages · Page 1 of 1 (latest)

pure lake
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regardless this is a nothingburger sorry for wasting time

willow wedge
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Assume SUBEXP = PSPACE and EXP = PSPACE
Then SUBEXP = EXP, contra time hierarchy, no? So you could prove anything in that case 😅

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I think that's the main sticking point, SUBEXP and EXP are already separated

pure lake
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my idea was proof by contradiction showing that SUBEXP = PSPACE -> EXP != PSPACE and SUBEXP != PSPACE -> EXP != PSPACE, therefore EXP != PSPACE

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the SUBEXP != PSPACE -> EXP != PSPACE almost, gets tantalizingly close to working

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but that splits into 2 possibilities, either PSPACE contains SUBEXP or it doesn't contain SUBEXP

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if PSPACE doesnt contain SUBEXP you get a trivial contradiction, because SUBEXP is contained strictly within EXP, that means that there is a problem in EXP not in PSPACE, so PSPACE != EXP

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The thing is, we also need to acount for PSPACE containing SUBEXP which seems unlikely but a P vs NP type seperation

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but like there should intuitionally be some problem in SUBEXPSPACE that needs at least SUBEXPSPACE that can also be solved in SUBEXPTIME

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so this reduces to SUBEXP vs SUBEXPSPACE

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if SUBEXP = SUBEXPSPACE then this is trivial

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if SUBEXP != SUBEXPSPACE then uhh

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fun