Signals from the future influencing the past
Ian Davis
that at the quantum level, not only does the past influence the future but
also the future influences the past.
The experiment consisted of measuring the spin of a large number of elementary
particles at 2:00 pm, 2:30 pm and sometimes measuring them also at 3:00 pm.
They used a very imprecise weak measuring technique which "mostly" ensured
that the spin was not changed by the measurement, while producing great
uncertainty about whether they had measured the actual spin accurately. The
question explored was how the imprecisely measured statistical spin would change
from 2:00 pm to 2:30 pm in the presence of a further measurement at 3:00pm
and in its absence. The difference in the change of spin between these
two experiments leads them to conclude that measuring at 3:00pm impacted
upon the results observed at 2:30pm.
They also explored the question of whether this implied that one could
predict the future from the results observed at 2:30pm .. ie would these
results oblige them to test or not test again at 3:00pm.. what would
happen if they exercised free will in not complying with the statistical
observations suggesting that they had or had not measured spins at 3:00pm.
Though the math isn't given the suggestion is that free will is nor
compromised by the observed results. The results at 2:30pm might suggest
that one was going to measure again at 3:00pm but the confidence level that
one will is so low, that if one doesn't the results can then be explained
as caused by the inate uncertainty inherent in the weak measurements
performed, which while in this case would be anomalous, are not statistically
significant.
The article stresses that the experiment is essentially statistical in
nature. There is no suggestion of anything definitive been possible to
say about the spin of any one photon, as consequence of a future
measurement. However, there was noticable and repeatable difference in
results measured at 2:30pm, under the two experimental conditions of
again measuring or not measuring at 3:00pm.
I found this interesting to read in print because it reinforces my
own belief (pet hobby horse) that time as we imagine it is illusionary,
and that past and future remain an integral part of our universe, even
though we only experience present. The article goes further suggesting
that time as we imagine it is a lie.
http://www.rochester.edu/news/show.php?id=3220
http://www.iop.org/EJ/article/1367-2630/12/1/013023/njp10_1_013023.html
http://www.fqxi.org/tools/download/__details/Tollaksen%20Azores%20Talk.ppt
"But we personally found it very useful to think of states propagating forward
and backward in time. In particular, during each measurement period we think
of two vectors, a ket propagating from the past time-boundary condition
towards the future and a bra propagating from the future time-boundary
condition towards the past. Each moment of time is therefore described by
these two vectors [13]. Of course, more generally each time moment can be
described by entangled bra and ket vectors or mixtures of them.
Thinking of vectors propagating forward and backward in time opens many new
possibilities that we found very intriguing. In particular, one can ask about
the possibility of having such time flow consistent with free-will.
As we show elsewhere, that it is consistent [15]. It is also possible to take
forward and backward in time propagation as a starting point for possible
modifications of quantum mechanics. Finally, it is tempting to try and
apply the idea of multi-time states in cosmological context, in particular
to speculate about the possibility that the Universe has both an initial and
a final state which are given independently of each other."
http://arxiv.org/PS_cache/arxiv/pdf/0712/0712.0320v1.pdf
Ian
Whiskers
> This months Discover magazine claims that scientists have detected evidence
> that at the quantum level, not only does the past influence the future but
> also the future influences the past.
[...]
That experiment doesn't seem to produce statistically significant results.
But there's a lot 'out there' about time reversal at the quantum level
<http://uk.ask.com/web?q=quantum+time+reversal&qsrc=19&o=312&l=dir>.
A recent incident with the new 'Large Hadron Collider' at CERN sparked a
brief flurry of speculation
<http://www.techradar.com/news/world-of-tech/future-tech/large-hadron-collider-sabotaged-by-time-travel--642543>
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-- ^^^^^^^^^^
-- Whiskers
-- ~~~~~~~~~~
Ian Davis
This argument seems a little far fetched. I expect the LHC to work eventually.
Ian.
Whiskers
Quantum mechanics is pretty far-fetched ;))