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is there any negative concept of time?

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can we assume time of the universe be 0 at big bang? also the pre existing conditions before big bang to be negative?

cygnus7

u cannot assume time before big bang to be negative..this is because conditions at big bang are not defined...because of the singularity, known laws of physics break down and what led to the big bang is unknown...

there is one theory that if curvature of space-time is negative time could be negative...and you could reach an event at a place in the past before it has occured..this is only a theory...

crack

ansering your question:
philospically time is assumed to have negative concept
scientifically: time is a theorotical unit invented to describe the passage of time.......therefore it is upto you to decide
to go with the philospher or scientist

yes it is assumed that time before big bang is negative ......not proved only theoritical concept

rate me if you plz

tarinbansal

Yes time can also be negative but that's by theory of relativity which is beyond our scope at this stage.

bhartibhanushali

yepp
time before arbitrary o time can be assumed as negative

also time before big bang is taken as negative

we know that time curve changes at plank's temp
also it changes if we travel velocity greater than light
then who knows that time can come into negative quadrant

usually negative time is seen in films {time machine used to see past}

feynmann

All of u are going too much beyond our scope .

Ok, I can point out two theories which are contradicting involving the very concept of the direction of time .

Yes , they are 2nd Law of thermodynamics & Maxwell,s eqn of electrodynamics.

2nd law states that entropy increases with time . ( according to Hawking it is because time itself is measued in the direction of increasing entropy . !!!! )

So if I want to reverse the arrow of time 2 nd law would no longer hold . So thermodynamics says that time has only one direction .

Now if u solve maxwell's wave eqn U WILL GET TWO SOLNS IN ONE OF WHICH THE WAVE MOVES BACKWARD IN TIME . Now generally this part of soln is neglected because it is considered to be ' UNPHYSICAL '. But , never mind ,this soln is COMPLETELY CONSISTENT WITH MAXWELL'S EQN .

In fact this backward moving wave was used by Feynmann ( Of course , the original one !!!!!!!!!!! ) himself in explaining the radiation reaction of electron .

Now tell me what to do ?

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