

Physicists demonstrate how time can seem to run backwards - jonbaer
http://www.dailymail.co.uk/sciencetech/article-3116792/Does-future-affect-PAST-Physicists-demonstrate-time-run-backwards.html

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madaxe_again
A) there are much better sources for science news than the daily fail - like
the paper -
[http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys...](http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3343.html)

B) this isn't necessarily retrocausality. Could equally be evidence in favour
of the pilot wave formulation of QM. No spooky time travel, just a standing
wave that guides the particles.

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andyjohnson0
Unfortunately, the letter published by Nature is paywalled after the first
page. Science Daily has a write-up at [1] which is also probably more
accessible to non-specialists.

Agree with you on the daily mail. A really _terrible_ source, and I have it
null routed on my machine. Any chance of the mods changing the link and title?

[1]
[http://www.sciencedaily.com/releases/2015/05/150527103110.ht...](http://www.sciencedaily.com/releases/2015/05/150527103110.htm)

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jjar
One of the many "benefits" of reading daily mail articles is you can go to the
comments section and be utterly confused.

>Time travels like a tube returning inside itself. It can do this as many
times as the space between the tube wall allows. Like when you take a rubber
glove off.

What?

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mdellabitta
[http://timecube.com/](http://timecube.com/)

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coldnebo
I know this article is a bad source, but why do scientists and the press
continue to use the provocative explanation of QM: "things don't exist unless
you look at them at the quantum level."

According to QM, things don't exist until they are _measured_ which is quite
different (unless you are tied to an anthropomorphic interpretation of
'observer').

Since there is no formal definition of observer that in any way limits such to
humans, an observer/measurer can in essence be any interacting particle in
physics-- measurement is an interaction.

This specialist notion is so far removed from the lay-person's interpretation
of an anthropomorphic observer creating reality wherever they look as to be
nonsense. Especially since the intuition is likely to be applied at the non-
quantum scale.

Systems of interacting particles are the _norm_ , _not_ the exception as our
careful laboratory experiments are crafted to be.

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cLeEOGPw
> things don't exist unless you look at them at the quantum level

But looking IS measuring.

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coldnebo
Sure. But either term is usually passive in classical contexts and always
destructive in QM contexts. You can't uncollapse a wave function!

Consider a twist on Schrödinger's cat experiment: there are two scientists, A
and B. The box can only be opened by one scientist at a time... the other
scientist must wait outside the room. Scientist A looks in the box and
collapses the wave function and sees that the cat is dead.

What is the probability that scientist B will see a dead cat when she opens
the box afterwards? 50%? 100%?

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GordonS
Ah, the Daily Hate, well-respected bastion of the truth...

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rrss1122
Thank you for that very helpful comment.

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deciplex
These results only imply time travel if you insist that something must either
be a wave or a particle in the first place, and that 'therefore' the particle
must be communicating with itself back through time somehow. Funny that a
thought experiment originally designed to challenge the notion of wave-
particle duality would instead be used to suggest _time travel_.

(Note that I don't think the researchers are doing this, but the Daily Mail
certainly is.)

