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#46173 11/19/12 06:00 PM
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Orac Offline OP
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This is some detail really for Bill G and Bill S but others may be interested

First experiment in on QM time versus standard definition of time

http://phys.org/news/2012-11-quantum-arrow-babar-asymmetry.html

As discussed before this would mean QM time is very different to GR/SR time where there is no reason for there to be a direction to time.

There are 3 more big experiments on QM time and I will link them as results come in.


New results in on the Higgs .. pretty boring behaving as expected :-)

http://resonaances.blogspot.com.au/


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Orac #46176 11/19/12 09:03 PM
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Ok, while my brain is fizzing on that thought let me try to interpret what they are saying about the time violation.

Normally you expect that if you take a movie of some interaction, say 2 pool balls on a table, then by watching the movie you won't be able to tell if the movie is running forward or backward. This I believe has been one of the questions about time for a long time. Why shouldn't time run either way.

But they are saying that when B mesons flip between the zero and even states you can tell the difference, because they do it at different rates. So if you watched a movie of a B meson flipping you could tell whether it was being run backward. So that at the quantum level, and by extension at the macro level, there is a preferred direction for time to run.

I think that's what they are saying.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.
Orac #46179 11/19/12 09:33 PM
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Nice one, Orac, keep 'em coming.

Thanks Bill, that saved a lot of pondering.


There never was nothing.
Bill #46180 11/20/12 01:09 AM
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Originally Posted By: Bill
Normally you expect that if you take a movie of some interaction, say 2 pool balls on a table, then by watching the movie you won't be able to tell if the movie is running forward or backward.

Sure you would. In the time reversed movie the accelerations would be reversed. You'd see at least one of the balls gain speed. We see entropy in action constantly, and generally have no difficulty spotting which movies have been reversed. The problem for physicists appears to have been in providing a fundamental explanation for it.


"Time is what prevents everything from happening at once" - John Wheeler
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And spot on Bill Gill.

Under GR/SR and all normal physics time is standard so lets say look at one of the standard equations of motion

Final velocity = Initial velocity + acceleration * time

or as we usually see it

v = u +at

Acceleration being positive or negative or time being positive or negative makes no difference you get the right answer so long as we have no other interactions.

What they are saying is this sort of time constancy is not holding at the low QM level energy exchanges that should be symmetrical aren't.

If QM knows the direction of time it would be the first thing we have found that does and the question then arises is it involved in it or is it simply reacting to it but most of all we know time is something tangible and that changes everything.

For those of you who really want to get under the hood I link Lubos's thread on the result and he explains why this really can't be the source of time directionality as such but it is evidence of what QM has been saying for a decade now that time is real and has to be for QM to work.

http://motls.blogspot.com.au/2012/11/babar-directly-measures-time-reversal.html

Last edited by Orac; 11/20/12 01:47 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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